/* pk.c
 *
 * Copyright (C) 2006-2023 wolfSSL Inc.
 *
 * This file is part of wolfSSL.
 *
 * wolfSSL is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * wolfSSL is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
 */

#ifdef HAVE_CONFIG_H
    #include <config.h>
#endif

#include <wolfssl/wolfcrypt/settings.h>

#include <wolfssl/internal.h>
#ifndef WC_NO_RNG
    #include <wolfssl/wolfcrypt/random.h>
#endif

#ifdef HAVE_ECC
    #include <wolfssl/wolfcrypt/ecc.h>
    #ifdef HAVE_SELFTEST
        /* point compression types. */
        #define ECC_POINT_COMP_EVEN 0x02
        #define ECC_POINT_COMP_ODD  0x03
        #define ECC_POINT_UNCOMP    0x04
    #endif
#endif
#ifndef WOLFSSL_HAVE_ECC_KEY_GET_PRIV
    /* FIPS build has replaced ecc.h. */
    #define wc_ecc_key_get_priv(key) (&((key)->k))
    #define WOLFSSL_HAVE_ECC_KEY_GET_PRIV
#endif

#if !defined(WOLFSSL_PK_INCLUDED)
    #ifndef WOLFSSL_IGNORE_FILE_WARN
        #warning pk.c does not need to be compiled separately from ssl.c
    #endif
#else

#ifndef NO_RSA
    #include <wolfssl/wolfcrypt/rsa.h>
#endif

/*******************************************************************************
 * COMMON FUNCTIONS
 ******************************************************************************/

/* Calculate the number of bytes require to represent a length value in ASN.
 *
 * @param [in] l  Length value to use.
 * @return  Number of bytes required to represent length value.
 */
#define ASN_LEN_SIZE(l)             \
    (((l) < 128) ? 1 : (((l) < 256) ? 2 : 3))

#if defined(OPENSSL_EXTRA)

#ifndef NO_ASN

#if (!defined(NO_FILESYSTEM) && (defined(OPENSSL_EXTRA) || \
     defined(OPENSSL_ALL))) || (!defined(NO_BIO) && defined(OPENSSL_EXTRA))
/* Convert the PEM encoding in the buffer to DER.
 *
 * @param [in]  pem        Buffer containing PEM encoded data.
 * @param [in]  pemSz      Size of data in buffer in bytes.
 * @param [in]  cb         Password callback when PEM encrypted.
 * @param [in]  pass       NUL terminated string for passphrase when PEM
 *                         encrypted.
 * @param [in]  keyType    Type of key to match against PEM header/footer.
 * @param [out] keyFormat  Format of key.
 * @param [out] der        Buffer holding DER encoding.
 * @return  Negative on failure.
 * @return  Number of bytes consumed on success.
 */
static int pem_mem_to_der(const char* pem, int pemSz, wc_pem_password_cb* cb,
    void* pass, int keyType, int* keyFormat, DerBuffer** der)
{
#ifdef WOLFSSL_SMALL_STACK
    EncryptedInfo* info = NULL;
#else
    EncryptedInfo info[1];
#endif /* WOLFSSL_SMALL_STACK */
    wc_pem_password_cb* localCb = NULL;
    int ret = 0;

    if (cb != NULL) {
        localCb = cb;
    }
    else if (pass != NULL) {
        localCb = wolfSSL_PEM_def_callback;
    }

#ifdef WOLFSSL_SMALL_STACK
    info = (EncryptedInfo*)XMALLOC(sizeof(EncryptedInfo), NULL,
        DYNAMIC_TYPE_ENCRYPTEDINFO);
    if (info == NULL) {
        WOLFSSL_ERROR_MSG("Error getting memory for EncryptedInfo structure");
        ret = MEMORY_E;
    }
#endif /* WOLFSSL_SMALL_STACK */

    if (ret == 0) {
        XMEMSET(info, 0, sizeof(EncryptedInfo));
        info->passwd_cb       = localCb;
        info->passwd_userdata = pass;

        /* Do not strip PKCS8 header */
        ret = PemToDer((const unsigned char *)pem, pemSz, keyType, der, NULL,
            info, keyFormat);
        if (ret < 0) {
            WOLFSSL_ERROR_MSG("Bad PEM To DER");
        }
    }
    if (ret >= 0) {
        ret = (int)info->consumed;
    }

#ifdef WOLFSSL_SMALL_STACK
    XFREE(info, NULL, DYNAMIC_TYPE_ENCRYPTEDINFO);
#endif

    return ret;
}
#endif

#if !defined(NO_RSA) || !defined(WOLFCRYPT_ONLY)
#ifndef NO_BIO
/* Read PEM data from a BIO and decode to DER in a new buffer.
 *
 * @param [in, out] bio        BIO object to read with.
 * @param [in]      cb         Password callback when PEM encrypted.
 * @param [in]      pass       NUL terminated string for passphrase when PEM
 *                             encrypted.
 * @param [in]      keyType    Type of key to match against PEM header/footer.
 * @param [out]     keyFormat  Format of key.
 * @param [out]     der        Buffer holding DER encoding.
 * @return  Negative on failure.
 * @return  Number of bytes consumed on success.
 */
static int pem_read_bio_key(WOLFSSL_BIO* bio, wc_pem_password_cb* cb,
    void* pass, int keyType, int* keyFormat, DerBuffer** der)
{
    int ret;
    char* mem = NULL;
    int memSz;
    int alloced = 0;

    ret = wolfssl_read_bio(bio, &mem, &memSz, &alloced);
    if (ret == 0) {
        ret = pem_mem_to_der(mem, memSz, cb, pass, keyType, keyFormat, der);
        /* Write left over data back to BIO if not a file BIO */
        if ((ret > 0) && ((memSz - ret) > 0) &&
                 (bio->type != WOLFSSL_BIO_FILE)) {
            int res = wolfSSL_BIO_write(bio, mem + ret, memSz - ret);
            if (res != memSz - ret) {
                WOLFSSL_ERROR_MSG("Unable to write back excess data");
                if (res < 0) {
                    ret = res;
                }
                else {
                    ret = MEMORY_E;
                }
            }
        }
        if (alloced) {
            XFREE(mem, NULL, DYNAMIC_TYPE_TMP_BUFFER);
        }
    }

    return ret;
}
#endif /* !NO_BIO */

#if !defined(NO_FILESYSTEM)
/* Read PEM data from a file and decode to DER in a new buffer.
 *
 * @param [in]  fp         File pointer to read with.
 * @param [in]  cb         Password callback when PEM encrypted.
 * @param [in]  pass       NUL terminated string for passphrase when PEM
 *                         encrypted.
 * @param [in]  keyType    Type of key to match against PEM header/footer.
 * @param [out] keyFormat  Format of key.
 * @param [out] der        Buffer holding DER encoding.
 * @return  Negative on failure.
 * @return  Number of bytes consumed on success.
 */
static int pem_read_file_key(XFILE fp, wc_pem_password_cb* cb, void* pass,
    int keyType, int* keyFormat, DerBuffer** der)
{
    int ret;
    char* mem = NULL;
    int memSz;

    ret = wolfssl_read_file(fp, &mem, &memSz);
    if (ret == 0) {
        ret = pem_mem_to_der(mem, memSz, cb, pass, keyType, keyFormat, der);
        XFREE(mem, NULL, DYNAMIC_TYPE_OPENSSL);
    }

    return ret;
}
#endif /* !NO_FILESYSTEM */
#endif

#if defined(OPENSSL_EXTRA) && ((!defined(NO_RSA) && defined(WOLFSSL_KEY_GEN)) \
    || !defined(WOLFCRYPT_ONLY))
/* Convert DER data to PEM in an allocated buffer.
 *
 * @param [in]  der    Buffer containing DER data.
 * @param [in]  derSz  Size of DER data in bytes.
 * @param [in]  type   Type of key being encoded.
 * @param [in]  heap   Heap hint for dynamic memory allocation.
 * @param [out] out    Allocated buffer containing PEM.
 * @param [out] outSz  Size of PEM encoding.
 * @return  1 on success.
 * @return  0 on error.
 */
static int der_to_pem_alloc(const unsigned char* der, int derSz, int type,
    void* heap, byte** out, int* outSz)
{
    int ret = 1;
    int pemSz;
    byte* pem = NULL;

    (void)heap;

    /* Convert DER to PEM - to get size. */
    pemSz = wc_DerToPem(der, (word32)derSz, NULL, 0, type);
    if (pemSz < 0) {
        ret = 0;
    }

    if (ret == 1) {
        /* Allocate memory for PEM to be encoded into. */
        pem = (byte*)XMALLOC((size_t)pemSz, heap, DYNAMIC_TYPE_TMP_BUFFER);
        if (pem == NULL) {
            ret = 0;
        }
    }

    /* Convert DER to PEM. */
    if ((ret == 1) && (wc_DerToPem(der, (word32)derSz, pem, (word32)pemSz,
            type) < 0)) {
        ret = 0;
        XFREE(pem, heap, DYNAMIC_TYPE_TMP_BUFFER);
        pem = NULL;
    }

    *out = pem;
    *outSz = pemSz;
    return ret;
}

#ifndef NO_BIO
/* Write the DER data as PEM into BIO.
 *
 * @param [in]      der    Buffer containing DER data.
 * @param [in]      derSz  Size of DER data in bytes.
 * @param [in, out] bio    BIO object to write with.
 * @param [in]      type   Type of key being encoded.
 * @return  1 on success.
 * @return  0 on error.
 */
static int der_write_to_bio_as_pem(const unsigned char* der, int derSz,
    WOLFSSL_BIO* bio, int type)
{
    int ret;
    int pemSz;
    byte* pem = NULL;

    ret = der_to_pem_alloc(der, derSz, type, bio->heap, &pem, &pemSz);
    if (ret == 1) {
        int len = wolfSSL_BIO_write(bio, pem, pemSz);
        if (len != pemSz) {
            WOLFSSL_ERROR_MSG("Unable to write full PEM to BIO");
            ret = 0;
        }
    }

    XFREE(pem, bio->heap, DYNAMIC_TYPE_TMP_BUFFER);
    return ret;
}
#endif
#endif

#if (!defined(NO_RSA) && defined(WOLFSSL_KEY_GEN)) || \
     (!defined(NO_DH) && defined(WOLFSSL_DH_EXTRA)) || \
     (defined(HAVE_ECC) && defined(WOLFSSL_KEY_GEN))
#if !defined(NO_FILESYSTEM)
/* Write the DER data as PEM into file pointer.
 *
 * @param [in] der    Buffer containing DER data.
 * @param [in] derSz  Size of DER data in bytes.
 * @param [in] fp     File pointer to write with.
 * @param [in] type   Type of key being encoded.
 * @param [in] heap   Heap hint for dynamic memory allocation.
 * @return  1 on success.
 * @return  0 on error.
 */
static int der_write_to_file_as_pem(const unsigned char* der, int derSz,
    XFILE fp, int type, void* heap)
{
    int ret;
    int pemSz;
    byte* pem = NULL;

    ret = der_to_pem_alloc(der, derSz, type, heap, &pem, &pemSz);
    if (ret == 1) {
        int len = (int)XFWRITE(pem, 1, (size_t)pemSz, fp);
        if (len != pemSz) {
            WOLFSSL_ERROR_MSG("Unable to write full PEM to BIO");
            ret = 0;
        }
    }

    XFREE(pem, NULL, DYNAMIC_TYPE_TMP_BUFFER);
    return ret;
}
#endif
#endif

#if defined(WOLFSSL_KEY_GEN) && defined(WOLFSSL_PEM_TO_DER)
/* Encrypt private key into PEM format.
 *
 * DER is encrypted in place.
 *
 * @param [in]  der         DER encoding of private key.
 * @param [in]  derSz       Size of DER in bytes.
 * @param [in]  cipher      EVP cipher.
 * @param [in]  passwd      Password to use with encryption.
 * @param [in]  passedSz    Size of password in bytes.
 * @param [out] cipherInfo  PEM cipher information lines.
 * @param [in]  maxDerSz    Maximum size of DER buffer.
 * @return  1 on success.
 * @return  0 on error.
 */
int EncryptDerKey(byte *der, int *derSz, const EVP_CIPHER* cipher,
    unsigned char* passwd, int passwdSz, byte **cipherInfo, int maxDerSz)
{
    int ret = 0;
    int paddingSz = 0;
    word32 idx;
    word32 cipherInfoSz;
#ifdef WOLFSSL_SMALL_STACK
    EncryptedInfo* info = NULL;
#else
    EncryptedInfo  info[1];
#endif

    WOLFSSL_ENTER("EncryptDerKey");

    /* Validate parameters. */
    if ((der == NULL) || (derSz == NULL) || (cipher == NULL) ||
            (passwd == NULL) || (cipherInfo == NULL)) {
        ret = BAD_FUNC_ARG;
    }

    #ifdef WOLFSSL_SMALL_STACK
    if (ret == 0) {
        /* Allocate encrypted info. */
        info = (EncryptedInfo*)XMALLOC(sizeof(EncryptedInfo), NULL,
            DYNAMIC_TYPE_ENCRYPTEDINFO);
        if (info == NULL) {
            WOLFSSL_MSG("malloc failed");
            ret = 0;
        }
    }
    #endif
    if (ret == 0) {
        /* Clear the encrypted info and set name. */
        XMEMSET(info, 0, sizeof(EncryptedInfo));
        XSTRNCPY(info->name, cipher, NAME_SZ - 1);
        info->name[NAME_SZ - 1] = '\0'; /* null term */

        /* Get encrypted info from name. */
        ret = wc_EncryptedInfoGet(info, info->name);
        if (ret != 0) {
            WOLFSSL_MSG("unsupported cipher");
        }
    }

    if (ret == 0) {
        /* Generate a random salt. */
        if (wolfSSL_RAND_bytes(info->iv, info->ivSz) != 1) {
            WOLFSSL_MSG("generate iv failed");
            ret = -1;
        }
    }

    if (ret == 0) {
        /* Calculate padding size - always a padding block. */
        paddingSz = info->ivSz - ((*derSz) % info->ivSz);
        /* Check der is big enough. */
        if (maxDerSz < (*derSz) + paddingSz) {
            WOLFSSL_MSG("not enough DER buffer allocated");
            ret = BAD_FUNC_ARG;
        }
    }
    if (ret == 0) {
        /* Set padding bytes to padding length. */
        XMEMSET(der + (*derSz), (byte)paddingSz, paddingSz);
        /* Add padding to DER size. */
        (*derSz) += (int)paddingSz;

        /* Encrypt DER buffer. */
        ret = wc_BufferKeyEncrypt(info, der, (word32)*derSz, passwd, passwdSz, WC_MD5);
        if (ret != 0) {
            WOLFSSL_MSG("encrypt key failed");
        }
    }

    if (ret == 0) {
        /* Create cipher info : 'cipher_name,Salt(hex)' */
        cipherInfoSz = (word32)(2 * info->ivSz + XSTRLEN(info->name) + 2);
        /* Allocate memory for PEM encryption lines. */
        *cipherInfo = (byte*)XMALLOC(cipherInfoSz, NULL, DYNAMIC_TYPE_STRING);
        if (*cipherInfo == NULL) {
            WOLFSSL_MSG("malloc failed");
            ret = MEMORY_E;
        }
    }
    if (ret == 0) {
        /* Copy in name and add on comma. */
        XSTRLCPY((char*)*cipherInfo, info->name, cipherInfoSz);
        XSTRLCAT((char*)*cipherInfo, ",", cipherInfoSz);

        /* Find end of string. */
        idx = (word32)XSTRLEN((char*)*cipherInfo);
        /* Calculate remaining bytes. */
        cipherInfoSz -= idx;

        /* Encode IV into PEM encryption lines. */
        ret = Base16_Encode(info->iv, info->ivSz, *cipherInfo + idx,
            &cipherInfoSz);
        if (ret != 0) {
            WOLFSSL_MSG("Base16_Encode failed");
            XFREE(*cipherInfo, NULL, DYNAMIC_TYPE_STRING);
            *cipherInfo = NULL;
        }
    }

#ifdef WOLFSSL_SMALL_STACK
    /* Free dynamically allocated info. */
    XFREE(info, NULL, DYNAMIC_TYPE_ENCRYPTEDINFO);
#endif
    return ret == 0;
}
#endif /* WOLFSSL_KEY_GEN || WOLFSSL_PEM_TO_DER */


#if defined(WOLFSSL_KEY_GEN) && \
    (defined(WOLFSSL_PEM_TO_DER) || defined(WOLFSSL_DER_TO_PEM)) && \
    (!defined(NO_RSA) || defined(HAVE_ECC))
/* Encrypt the DER in PEM format.
 *
 * @param [in]  der       DER encoded private key.
 * @param [in]  derSz     Size of DER in bytes.
 * @param [in]  cipher    EVP cipher.
 * @param [in]  passwd    Password to use in encryption.
 * @param [in]  passwdSz  Size of password in bytes.
 * @param [in]  type      PEM type of write out.
 * @param [in]  heap      Dynamic memory hint.
 * @param [out] out       Allocated buffer containing PEM encoding.
 *                        heap was NULL and dynamic type is DYNAMIC_TYPE_KEY.
 * @param [out] outSz     Size of PEM encoding in bytes.
 * @return  1 on success.
 * @return  0 on failure.
 */
static int der_to_enc_pem_alloc(unsigned char* der, int derSz,
    const EVP_CIPHER *cipher, unsigned char *passwd, int passwdSz, int type,
    void* heap, byte** out, int* outSz)
{
    int ret = 1;
    byte* tmp = NULL;
    byte* cipherInfo = NULL;
    int pemSz = 0;

    /* Macro doesn't always use it. */
    (void)heap;

    /* Encrypt DER buffer if required. */
    if ((ret == 1) && (passwd != NULL) && (passwdSz > 0) && (cipher != NULL)) {
        int blockSz = wolfSSL_EVP_CIPHER_block_size(cipher);
        byte *tmpBuf;

        /* Add space for padding. */
        tmpBuf = (byte*)XREALLOC(der, (size_t)(derSz + blockSz), heap,
            DYNAMIC_TYPE_TMP_BUFFER);
        if (tmpBuf == NULL) {
            WOLFSSL_ERROR_MSG("Extending DER buffer failed");
            ret = 0; /* der buffer is free'd at the end of the function */
        }
        else {
            der = tmpBuf;

            /* Encrypt DER inline. */
            ret = EncryptDerKey(der, &derSz, cipher, passwd, passwdSz,
                &cipherInfo, derSz + blockSz);
            if (ret != 1) {
                WOLFSSL_ERROR_MSG("EncryptDerKey failed");
            }
        }
    }

    if (ret == 1) {
        /* Calculate PEM encoding size. */
        pemSz = wc_DerToPemEx(der, (word32)derSz, NULL, 0, cipherInfo, type);
        if (pemSz <= 0) {
            WOLFSSL_ERROR_MSG("wc_DerToPemEx failed");
            ret = 0;
        }
    }
    if (ret == 1) {
        /* Allocate space for PEM encoding plus a NUL terminator. */
        tmp = (byte*)XMALLOC((size_t)(pemSz + 1), NULL, DYNAMIC_TYPE_KEY);
        if (tmp == NULL) {
            WOLFSSL_ERROR_MSG("malloc failed");
            ret = 0;
        }
    }
    if (ret == 1) {
        /* DER to PEM */
        pemSz = wc_DerToPemEx(der, (word32)derSz, tmp, (word32)pemSz,
            cipherInfo, type);
        if (pemSz <= 0) {
            WOLFSSL_ERROR_MSG("wc_DerToPemEx failed");
            ret = 0;
        }
    }
    if (ret == 1) {
        /* NUL terminate string - PEM.  */
        tmp[pemSz] = 0x00;
        /* Return allocated buffer and size. */
        *out = tmp;
        *outSz = pemSz;
        /* Don't free returning buffer. */
        tmp = NULL;
    }

    XFREE(tmp, NULL, DYNAMIC_TYPE_KEY);
    XFREE(cipherInfo, NULL, DYNAMIC_TYPE_STRING);
    XFREE(der, heap, DYNAMIC_TYPE_TMP_BUFFER);

    return ret;
}
#endif

#endif /* !NO_ASN */

#if !defined(NO_CERTS) && defined(XFPRINTF) && !defined(NO_FILESYSTEM) && \
    !defined(NO_STDIO_FILESYSTEM) && (!defined(NO_RSA) || !defined(NO_DSA) || \
    defined(HAVE_ECC)) && defined(OPENSSL_EXTRA)
/* Print the number bn in hex with name field and indentation indent to file fp.
 *
 * Used by wolfSSL_DSA_print_fp, wolfSSL_RSA_print_fp and
 * wolfSSL_EC_KEY_print_fp to print DSA, RSA and ECC keys and parameters.
 *
 * @param [in] fp      File pointer to write to.
 * @param [in] indent  Number of spaces to prepend to each line.
 * @param [in] field   Name of field.
 * @param [in] bn      Big number to print.
 * @return  1 on success.
 * @return  0 on failure.
 * @return  BAD_FUNC_ARG when fp is invalid, indent is less than 0, or field or
 *          bn or NULL.
 */
static int pk_bn_field_print_fp(XFILE fp, int indent, const char* field,
    const WOLFSSL_BIGNUM* bn)
{
    static const int HEX_INDENT = 4;
    static const int MAX_DIGITS_PER_LINE = 30;

    int ret = 1;
    int i = 0;
    char* buf = NULL;

    /* Internal function - assume parameters are valid. */

    /* Convert BN to hexadecimal character array (allocates buffer). */
    buf = wolfSSL_BN_bn2hex(bn);
    if (buf == NULL) {
        ret = 0;
    }
    if (ret == 1) {
        /* Print leading spaces, name and spaces before data. */
        if (indent > 0) {
            if (XFPRINTF(fp, "%*s", indent, "") < 0)
                ret = 0;
        }
    }
    if (ret == 1) {
        if (XFPRINTF(fp, "%s:\n", field) < 0)
            ret = 0;
    }
    if (ret == 1) {
        if (indent > 0) {
            if (XFPRINTF(fp, "%*s", indent, "") < 0)
                ret = 0;
        }
    }
    if (ret == 1) {
        if (XFPRINTF(fp, "%*s", HEX_INDENT, "") < 0)
            ret = 0;
    }
    if (ret == 1) {
        /* Print first byte - should always exist. */
        if ((buf[i] != '\0') && (buf[i+1] != '\0')) {
            if (XFPRINTF(fp, "%c", buf[i++]) < 0)
                ret = 0;
            else if (XFPRINTF(fp, "%c", buf[i++]) < 0)
                    ret = 0;
        }
    }
    if (ret == 1) {
        /* Print each hexadecimal character with byte separator. */
        while ((buf[i] != '\0') && (buf[i+1] != '\0')) {
            /* Byte separator every two nibbles - one byte. */
            if (XFPRINTF(fp, ":") < 0) {
                ret = 0;
                break;
            }
            /* New line after every 15 bytes - 30 nibbles. */
            if (i % MAX_DIGITS_PER_LINE == 0) {
                if (XFPRINTF(fp, "\n") < 0) {
                    ret = 0;
                    break;
                }
                if (indent > 0) {
                    if (XFPRINTF(fp, "%*s", indent, "") < 0) {
                        ret = 0;
                        break;
                    }
                }
                if (XFPRINTF(fp, "%*s", HEX_INDENT, "") < 0) {
                    ret = 0;
                    break;
                }
            }
            /* Print two nibbles - one byte. */
            if (XFPRINTF(fp, "%c", buf[i++]) < 0) {
                ret = 0;
                break;
            }
            if (XFPRINTF(fp, "%c", buf[i++]) < 0) {
                ret = 0;
                break;
            }
        }
        /* Ensure on new line after data. */
        if (XFPRINTF(fp, "\n") < 0) {
            ret = 0;
        }
    }

    /* Dispose of any allocated character array. */
    XFREE(buf, NULL, DYNAMIC_TYPE_OPENSSL);

    return ret;
}
#endif /* !NO_CERTS && XFPRINTF && !NO_FILESYSTEM && !NO_STDIO_FILESYSTEM &&
        * (!NO_DSA || !NO_RSA || HAVE_ECC) */

#if defined(XSNPRINTF) && !defined(NO_BIO) && !defined(NO_RSA)
/* snprintf() must be available */

/* Maximum number of extra indent spaces on each line. */
#define PRINT_NUM_MAX_INDENT        48
/* Maximum size of a line containing a value. */
#define PRINT_NUM_MAX_VALUE_LINE    PRINT_NUM_MAX_INDENT
/* Number of leading spaces on each line. */
#define PRINT_NUM_INDENT_CNT        4
/* Indent spaces for number lines. */
#define PRINT_NUM_INDENT            "    "
/* 4 leading spaces and 15 bytes with colons is a complete line. */
#define PRINT_NUM_MAX_DIGIT_LINE   (PRINT_NUM_INDENT_CNT + 3 * 15)

/* Print indent to BIO.
 *
 * @param [in] bio      BIO object to write to.
 * @param [in] line     Buffer to put characters to before writing to BIO.
 * @param [in] lineLen  Length of buffer.
 * @return  1 on success.
 * @return  0 on failure.
 */
static int wolfssl_print_indent(WOLFSSL_BIO* bio, char* line, int lineLen,
    int indent)
{
    int ret = 1;

    if (indent > 0) {
        /* Print indent spaces. */
        int len_wanted = XSNPRINTF(line, (size_t)lineLen, "%*s", indent, " ");
        if (len_wanted >= lineLen) {
            WOLFSSL_ERROR_MSG("Buffer overflow formatting indentation");
            ret = 0;
        }
        else {
            /* Write indents string to BIO */
            if (wolfSSL_BIO_write(bio, line, len_wanted) <= 0) {
                ret = 0;
            }
        }
    }

    return ret;
}

/* Print out name, and value in decimal and hex to BIO.
 *
 * @param [in] bio     BIO object to write to.
 * @param [in] value   MP integer to write.
 * @param [in] name    Name of value.
 * @param [in] indent  Number of leading spaces before line.
 * @return  1 on success.
 * @return  0 on failure.
 */
static int wolfssl_print_value(WOLFSSL_BIO* bio, mp_int* value,
    const char* name, int indent)
{
    int ret = 1;
    int len;
    char line[PRINT_NUM_MAX_VALUE_LINE + 1];

    /* Get the length of hex encoded value. */
    len = mp_unsigned_bin_size(value);
    /* Value must no more than 32-bits - 4 bytes. */
    if ((len < 0) || (len > 4)) {
        WOLFSSL_ERROR_MSG("Error getting exponent size");
        ret = 0;
    }
    if (ret == 1) {
        /* Print any indent spaces. */
        ret = wolfssl_print_indent(bio, line, sizeof(line), indent);
    }
    if (ret == 1) {
        /* Get 32-bits of value. */
        word32 v = (word32)value->dp[0];
        /* Print the line to the string. */
        len = (int)XSNPRINTF(line, sizeof(line), "%s %u (0x%x)\n", name, v,
            v);
        if (len >= (int)sizeof(line)) {
            WOLFSSL_ERROR_MSG("Buffer overflow while formatting value");
            ret = 0;
        } else {
            /* Write string to BIO */
            if (wolfSSL_BIO_write(bio, line, len) <= 0) {
                ret = 0;
            }
        }
    }

    return ret;
}

/* Print out name and multi-precision number to BIO.
 *
 * @param [in] bio     BIO object to write to.
 * @param [in] num     MP integer to write.
 * @param [in] name    Name of value.
 * @param [in] indent  Number of leading spaces before each line.
 * @return  1 on success.
 * @return  0 on failure.
 */
static int wolfssl_print_number(WOLFSSL_BIO* bio, mp_int* num, const char* name,
    int indent)
{
    int ret = 1;
    int rawLen = 0;
    byte* rawKey = NULL;
    char line[PRINT_NUM_MAX_DIGIT_LINE + 1];
    int li = 0; /* Line index. */
    int i;

    /* Allocate a buffer to hold binary encoded data. */
    rawLen = mp_unsigned_bin_size(num);
    if (rawLen == 0) {
        WOLFSSL_ERROR_MSG("Invalid number");
        ret = 0;
    }
    if (ret == 1) {
        rawKey = (byte*)XMALLOC((size_t)rawLen, NULL, DYNAMIC_TYPE_TMP_BUFFER);
        if (rawKey == NULL) {
            WOLFSSL_ERROR_MSG("Memory allocation error");
            ret = 0;
        }
    }
    /* Encode number as big-endian byte array. */
    if ((ret == 1) && (mp_to_unsigned_bin(num, rawKey) < 0)) {
        ret = 0;
    }

    if (ret == 1) {
        /* Print any indent spaces. */
        ret = wolfssl_print_indent(bio, line, sizeof(line), indent);
    }
    if (ret == 1) {
        /* Print header string line to string. */
        li = XSNPRINTF(line, sizeof(line), "%s\n", name);
        if (li >= (int)sizeof(line)) {
            WOLFSSL_ERROR_MSG("Buffer overflow formatting name");
            ret = 0;
        }
        else {
            if (wolfSSL_BIO_write(bio, line, li) <= 0) {
                ret = 0;
            }
        }
    }
    if (ret == 1) {
        /* Print any indent spaces. */
        ret = wolfssl_print_indent(bio, line, sizeof(line), indent);
    }
    if (ret == 1) {
        /* Start first digit line with spaces.
         * Writing out zeros ensures number is a positive value. */
        li = XSNPRINTF(line, sizeof(line), PRINT_NUM_INDENT "%s",
            mp_leading_bit(num) ?  "00:" : "");
        if (li >= (int)sizeof(line)) {
            WOLFSSL_ERROR_MSG("Buffer overflow formatting spaces");
            ret = 0;
        }
    }

    /* Put out each line of numbers. */
    for (i = 0; (ret == 1) && (i < rawLen); i++) {
        /* Encode another byte as 2 hex digits and append colon. */
        int len_wanted = XSNPRINTF(line + li, sizeof(line) - (size_t)li,
                                   "%02x:", rawKey[i]);
        /* Check if there was room -- if not, print the current line, not
         * including the newest octet.
         */
        if (len_wanted >= (int)sizeof(line) - li) {
            /* bump current octet to the next line. */
            --i;
            /* More bytes coming so add a line break. */
            line[li++] = '\n';
            /* Write out the line. */
            if (wolfSSL_BIO_write(bio, line, li) <= 0) {
                ret = 0;
            }
            if (ret == 1) {
                /* Print any indent spaces. */
                ret = wolfssl_print_indent(bio, line, sizeof(line), indent);
            }
            /* Put the leading spaces on new line. */
            XSTRNCPY(line, PRINT_NUM_INDENT, PRINT_NUM_INDENT_CNT + 1);
            li = PRINT_NUM_INDENT_CNT;
        }
        else {
            li += len_wanted;
        }
    }

    if (ret == 1) {
        /* Put out last line - replace last colon with carriage return. */
        line[li-1] = '\n';
        if (wolfSSL_BIO_write(bio, line, li) <= 0) {
            ret = 0;
        }
    }

    /* Dispose of any allocated data. */
    XFREE(rawKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
    return ret;
}

#endif /* XSNPRINTF && !NO_BIO && !NO_RSA */

#endif /* OPENSSL_EXTRA */

#if !defined(NO_CERTS) || (defined(OPENSSL_EXTRA) && (!defined(NO_RSA) || \
    (!defined(NO_DH) && defined(HAVE_FIPS) && !FIPS_VERSION_GT(2,0)) || \
    defined(HAVE_ECC)))

/* Uses the DER SEQUENCE to determine size of DER data.
 *
 * Outer SEQUENCE encapsulates all the DER encoding.
 * Add the length of the SEQUENCE data to the length of the SEQUENCE header.
 *
 * @param [in] seq  Buffer holding DER encoded sequence.
 * @param [in] len  Length of data in buffer (may be larger than SEQ).
 * @return  Size of complete DER encoding on success.
 * @return  0 on failure.
 */
static int wolfssl_der_length(const unsigned char* seq, int len)
{
    int ret = 0;
    word32 i = 0;

    /* Check it is a SEQUENCE and get the length of the underlying data.
     * i is updated to be after SEQUENCE header bytes.
     */
    if (GetSequence_ex(seq, &i, &ret, (word32)len, 0) >= 0) {
        /* Add SEQUENCE header length to underlying data length. */
        ret += (int)i;
    }

    return ret;
}

#endif

/*******************************************************************************
 * START OF RSA API
 ******************************************************************************/

#ifndef NO_RSA

/*
 * RSA METHOD
 * Could be used to hold function pointers to implementations of RSA operations.
 */

#if defined(OPENSSL_EXTRA)
/* Return a blank RSA method and set the name and flags.
 *
 * Only one implementation of RSA operations.
 * name is duplicated.
 *
 * @param [in] name   Name to use in method.
 * @param [in] flags  Flags to set into method.
 * @return  Newly allocated RSA method on success.
 * @return  NULL on failure.
 */
WOLFSSL_RSA_METHOD *wolfSSL_RSA_meth_new(const char *name, int flags)
{
    WOLFSSL_RSA_METHOD* meth = NULL;
    int name_len = 0;
    int err;

    /* Validate name is not NULL. */
    err = (name == NULL);
    if (!err) {
        /* Allocate an RSA METHOD to return. */
        meth = (WOLFSSL_RSA_METHOD*)XMALLOC(sizeof(WOLFSSL_RSA_METHOD), NULL,
            DYNAMIC_TYPE_OPENSSL);
        err = (meth == NULL);
    }
    if (!err) {
        XMEMSET(meth, 0, sizeof(*meth));
        meth->flags = flags;
        meth->dynamic = 1;

        name_len = (int)XSTRLEN(name);
        meth->name = (char*)XMALLOC((size_t)(name_len + 1), NULL,
            DYNAMIC_TYPE_OPENSSL);
        err = (meth->name == NULL);
    }
    if (!err) {
        XMEMCPY(meth->name, name, (size_t)(name_len + 1));
    }

    if (err) {
        /* meth->name won't be allocated on error. */
        XFREE(meth, NULL, DYNAMIC_TYPE_OPENSSL);
        meth = NULL;
    }
    return meth;
}

/* Default RSA method is one with wolfSSL name and no flags.
 *
 * @return  Newly allocated wolfSSL RSA method on success.
 * @return  NULL on failure.
 */
const WOLFSSL_RSA_METHOD* wolfSSL_RSA_get_default_method(void)
{
    static const WOLFSSL_RSA_METHOD wolfssl_rsa_meth = {
        0, /* No flags. */
        (char*)"wolfSSL RSA",
        0  /* Static definition. */
    };
    return &wolfssl_rsa_meth;
}

/* Dispose of RSA method and allocated data.
 *
 * @param [in] meth  RSA method to free.
 */
void wolfSSL_RSA_meth_free(WOLFSSL_RSA_METHOD *meth)
{
    /* Free method if available and dynamically allocated. */
    if ((meth != NULL) && meth->dynamic) {
        /* Name was duplicated and must be freed. */
        XFREE(meth->name, NULL, DYNAMIC_TYPE_OPENSSL);
        /* Dispose of RSA method. */
        XFREE(meth, NULL, DYNAMIC_TYPE_OPENSSL);
    }
}

#ifndef NO_WOLFSSL_STUB
/* Stub function for any RSA method setting function.
 *
 * Nothing is stored - not even flags or name.
 *
 * @param [in] meth  RSA method.
 * @param [in] p     A pointer.
 * @return  1 to indicate success.
 */
int wolfSSL_RSA_meth_set(WOLFSSL_RSA_METHOD *meth, void* p)
{
    WOLFSSL_STUB("RSA_METHOD is not implemented.");

    (void)meth;
    (void)p;

    return 1;
}
#endif /* !NO_WOLFSSL_STUB */
#endif /* OPENSSL_EXTRA */

/*
 * RSA constructor/deconstructor APIs
 */

#if defined(OPENSSL_EXTRA) || defined(OPENSSL_EXTRA_X509_SMALL)
/* Dispose of RSA key and allocated data.
 *
 * Cannot use rsa after this call.
 *
 * @param [in] rsa  RSA key to free.
 */
void wolfSSL_RSA_free(WOLFSSL_RSA* rsa)
{
    int doFree = 1;

    WOLFSSL_ENTER("wolfSSL_RSA_free");

    /* Validate parameter. */
    if (rsa == NULL) {
        doFree = 0;
    }
    if (doFree) {
        int err;

        /* Decrement reference count. */
        wolfSSL_RefDec(&rsa->ref, &doFree, &err);
    #ifndef WOLFSSL_REFCNT_ERROR_RETURN
        (void)err;
    #endif
    }
    if (doFree) {
        void* heap = rsa->heap;

        /* Dispose of allocated reference counting data. */
        wolfSSL_RefFree(&rsa->ref);

    #ifdef HAVE_EX_DATA_CLEANUP_HOOKS
        wolfSSL_CRYPTO_cleanup_ex_data(&rsa->ex_data);
    #endif

        if (rsa->internal != NULL) {
        #if !defined(HAVE_FIPS) && defined(WC_RSA_BLINDING)
            /* Check if RNG is owned before freeing it. */
            if (rsa->ownRng) {
                WC_RNG* rng = ((RsaKey*)(rsa->internal))->rng;
                if ((rng != NULL) && (rng != wolfssl_get_global_rng())) {
                    wc_FreeRng(rng);
                    XFREE(rng, heap, DYNAMIC_TYPE_RNG);
                }
                /* RNG isn't freed by wolfCrypt RSA free. */
            }
        #endif
            /* Dispose of allocated data in wolfCrypt RSA key. */
            wc_FreeRsaKey((RsaKey*)rsa->internal);
            /* Dispose of memory for wolfCrypt RSA key. */
            XFREE(rsa->internal, heap, DYNAMIC_TYPE_RSA);
        }

        /* Dispose of external representation of RSA values. */
        wolfSSL_BN_clear_free(rsa->iqmp);
        wolfSSL_BN_clear_free(rsa->dmq1);
        wolfSSL_BN_clear_free(rsa->dmp1);
        wolfSSL_BN_clear_free(rsa->q);
        wolfSSL_BN_clear_free(rsa->p);
        wolfSSL_BN_clear_free(rsa->d);
        wolfSSL_BN_free(rsa->e);
        wolfSSL_BN_free(rsa->n);

    #if defined(OPENSSL_EXTRA)
        if (rsa->meth) {
            wolfSSL_RSA_meth_free((WOLFSSL_RSA_METHOD*)rsa->meth);
        }
    #endif

        /* Set back to NULLs for safety. */
        ForceZero(rsa, sizeof(*rsa));

        XFREE(rsa, heap, DYNAMIC_TYPE_RSA);
        (void)heap;
    }
}

/* Allocate and initialize a new RSA key.
 *
 * Not OpenSSL API.
 *
 * @param [in] heap   Heap hint for dynamic memory allocation.
 * @param [in] devId  Device identifier value.
 * @return  RSA key on success.
 * @return  NULL on failure.
 */
WOLFSSL_RSA* wolfSSL_RSA_new_ex(void* heap, int devId)
{
    WOLFSSL_RSA* rsa = NULL;
    RsaKey* key = NULL;
    int err = 0;
    int rsaKeyInited = 0;

    WOLFSSL_ENTER("wolfSSL_RSA_new");

    /* Allocate memory for new wolfCrypt RSA key. */
    key = (RsaKey*)XMALLOC(sizeof(RsaKey), heap, DYNAMIC_TYPE_RSA);
    if (key == NULL) {
        WOLFSSL_ERROR_MSG("wolfSSL_RSA_new malloc RsaKey failure");
        err = 1;
    }
    if (!err) {
        /* Allocate memory for new RSA key. */
        rsa = (WOLFSSL_RSA*)XMALLOC(sizeof(WOLFSSL_RSA), heap,
            DYNAMIC_TYPE_RSA);
        if (rsa == NULL) {
            WOLFSSL_ERROR_MSG("wolfSSL_RSA_new malloc WOLFSSL_RSA failure");
            err = 1;
        }
    }
    if (!err) {
        /* Clear all fields of RSA key. */
        XMEMSET(rsa, 0, sizeof(WOLFSSL_RSA));
        /* Cache heap to use for all allocations. */
        rsa->heap = heap;
    #ifdef OPENSSL_EXTRA
        /* Always have a method set. */
        rsa->meth = wolfSSL_RSA_get_default_method();
    #endif

        /* Initialize reference counting. */
        wolfSSL_RefInit(&rsa->ref, &err);
#ifdef WOLFSSL_REFCNT_ERROR_RETURN
    }
    if (!err) {
#endif
        /* Initialize wolfCrypt RSA key. */
        if (wc_InitRsaKey_ex(key, heap, devId) != 0) {
            WOLFSSL_ERROR_MSG("InitRsaKey WOLFSSL_RSA failure");
            err = 1;
        }
        else {
            rsaKeyInited = 1;
        }
    }
    #if !defined(HAVE_FIPS) && defined(WC_RSA_BLINDING)
    if (!err) {
        WC_RNG* rng;

        /* Create a local RNG. */
        rng = (WC_RNG*)XMALLOC(sizeof(WC_RNG), heap, DYNAMIC_TYPE_RNG);
        if ((rng != NULL) && (wc_InitRng_ex(rng, heap, devId) != 0)) {
            WOLFSSL_MSG("InitRng failure, attempting to use global RNG");
            XFREE(rng, heap, DYNAMIC_TYPE_RNG);
            rng = NULL;
        }

        rsa->ownRng = 1;
        if (rng == NULL) {
            /* Get the wolfSSL global RNG - not thread safe. */
            rng = wolfssl_get_global_rng();
            rsa->ownRng = 0;
        }
        if (rng == NULL) {
            /* Couldn't create global either. */
            WOLFSSL_ERROR_MSG("wolfSSL_RSA_new no WC_RNG for blinding");
            err = 1;
        }
        else {
            /* Set the local or global RNG into the wolfCrypt RSA key. */
            (void)wc_RsaSetRNG(key, rng);
            /* Won't fail as key and rng are not NULL. */
        }
    }
    #endif /* !HAVE_FIPS && WC_RSA_BLINDING */
    if (!err) {
        /* Set wolfCrypt RSA key into RSA key. */
        rsa->internal = key;
        /* Data from external RSA key has not been set into internal one. */
        rsa->inSet = 0;
    }

    if (err) {
        /* Dispose of any allocated data on error. */
        /* No failure after RNG allocation - no need to free RNG. */
        if (rsaKeyInited) {
            wc_FreeRsaKey(key);
        }
        XFREE(key, heap, DYNAMIC_TYPE_RSA);
        XFREE(rsa, heap, DYNAMIC_TYPE_RSA);
        /* Return NULL. */
        rsa = NULL;
    }
    return rsa;
}

/* Allocate and initialize a new RSA key.
 *
 * @return  RSA key on success.
 * @return  NULL on failure.
 */
WOLFSSL_RSA* wolfSSL_RSA_new(void)
{
    /* Call wolfSSL API to do work. */
    return wolfSSL_RSA_new_ex(NULL, INVALID_DEVID);
}

/* Increments ref count of RSA key.
 *
 * @param [in, out] rsa  RSA key.
 * @return  1 on success
 * @return  0 on error
 */
int wolfSSL_RSA_up_ref(WOLFSSL_RSA* rsa)
{
    int err = 0;
    if (rsa != NULL) {
        wolfSSL_RefInc(&rsa->ref, &err);
    }
    return !err;
}

#endif /* OPENSSL_EXTRA || OPENSSL_EXTRA_X509_SMALL */

#ifdef OPENSSL_EXTRA

#if defined(WOLFSSL_KEY_GEN)

/* Allocate a new RSA key and make it a copy.
 *
 * Encodes to and from DER to copy.
 *
 * @param [in] rsa  RSA key to duplicate.
 * @return  RSA key on success.
 * @return  NULL on error.
 */
WOLFSSL_RSA* wolfSSL_RSAPublicKey_dup(WOLFSSL_RSA *rsa)
{
    WOLFSSL_RSA* ret = NULL;
    int derSz = 0;
    byte* derBuf = NULL;
    int err;

    WOLFSSL_ENTER("wolfSSL_RSAPublicKey_dup");

    err = (rsa == NULL);
    if (!err) {
        /* Create a new RSA key to return. */
        ret = wolfSSL_RSA_new();
        if (ret == NULL) {
            WOLFSSL_ERROR_MSG("Error creating a new WOLFSSL_RSA structure");
            err = 1;
        }
    }
    if (!err) {
        /* Encode RSA public key to copy to DER - allocates DER buffer. */
        if ((derSz = wolfSSL_RSA_To_Der(rsa, &derBuf, 1, rsa->heap)) < 0) {
            WOLFSSL_ERROR_MSG("wolfSSL_RSA_To_Der failed");
            err = 1;
        }
    }
    if (!err) {
        /* Decode DER of the RSA public key into new key. */
        if (wolfSSL_RSA_LoadDer_ex(ret, derBuf, derSz,
                WOLFSSL_RSA_LOAD_PUBLIC) != 1) {
            WOLFSSL_ERROR_MSG("wolfSSL_RSA_LoadDer_ex failed");
            err = 1;
        }
    }

    /* Dispose of any allocated DER buffer. */
    XFREE(derBuf, rsa ? rsa->heap : NULL, DYNAMIC_TYPE_ASN1);
    if (err) {
        /* Disposes of any created RSA key - on error. */
        wolfSSL_RSA_free(ret);
        ret = NULL;
    }
    return ret;
}

/* wolfSSL_RSAPrivateKey_dup not supported */

#endif /* WOLFSSL_KEY_GEN */

static int wolfSSL_RSA_To_Der_ex(WOLFSSL_RSA* rsa, byte** outBuf, int publicKey,
    void* heap);

/*
 * RSA to/from bin APIs
 */

/* Convert RSA public key data to internal.
 *
 * Creates new RSA key from the DER encoded RSA public key.
 *
 * @param [out]     out      Pointer to RSA key to return through. May be NULL.
 * @param [in, out] derBuf   Pointer to start of DER encoded data.
 * @param [in]      derSz    Length of the data in the DER buffer.
 * @return  RSA key on success.
 * @return  NULL on failure.
 */
WOLFSSL_RSA *wolfSSL_d2i_RSAPublicKey(WOLFSSL_RSA **out,
    const unsigned char **derBuf, long derSz)
{
    WOLFSSL_RSA *rsa = NULL;
    int err = 0;

    WOLFSSL_ENTER("wolfSSL_d2i_RSAPublicKey");

    /* Validate parameters. */
    if (derBuf == NULL) {
        WOLFSSL_ERROR_MSG("Bad argument");
        err = 1;
    }
    /* Create a new RSA key to return. */
    if ((!err) && ((rsa = wolfSSL_RSA_new()) == NULL)) {
        WOLFSSL_ERROR_MSG("RSA_new failed");
        err = 1;
    }
    /* Decode RSA key from DER. */
    if ((!err) && (wolfSSL_RSA_LoadDer_ex(rsa, *derBuf, (int)derSz,
            WOLFSSL_RSA_LOAD_PUBLIC) != 1)) {
        WOLFSSL_ERROR_MSG("RSA_LoadDer failed");
        err = 1;
    }
    if ((!err) && (out != NULL)) {
        /* Return through parameter too. */
        *out = rsa;
        /* Move buffer on by the used amount. */
        *derBuf += wolfssl_der_length(*derBuf, (int)derSz);
    }

    if (err) {
        /* Dispose of any created RSA key. */
        wolfSSL_RSA_free(rsa);
        rsa = NULL;
    }
    return rsa;
}

/* Convert RSA private key data to internal.
 *
 * Create a new RSA key from the DER encoded RSA private key.
 *
 * @param [out]     out      Pointer to RSA key to return through. May be NULL.
 * @param [in, out] derBuf   Pointer to start of DER encoded data.
 * @param [in]      derSz    Length of the data in the DER buffer.
 * @return  RSA key on success.
 * @return  NULL on failure.
 */
WOLFSSL_RSA *wolfSSL_d2i_RSAPrivateKey(WOLFSSL_RSA **out,
    const unsigned char **derBuf, long derSz)
{
    WOLFSSL_RSA *rsa = NULL;
    int err = 0;

    WOLFSSL_ENTER("wolfSSL_d2i_RSAPublicKey");

    /* Validate parameters. */
    if (derBuf == NULL) {
        WOLFSSL_ERROR_MSG("Bad argument");
        err = 1;
    }
    /* Create a new RSA key to return. */
    if ((!err) && ((rsa = wolfSSL_RSA_new()) == NULL)) {
        WOLFSSL_ERROR_MSG("RSA_new failed");
        err = 1;
    }
    /* Decode RSA key from DER. */
    if ((!err) && (wolfSSL_RSA_LoadDer_ex(rsa, *derBuf, (int)derSz,
            WOLFSSL_RSA_LOAD_PRIVATE) != 1)) {
        WOLFSSL_ERROR_MSG("RSA_LoadDer failed");
        err = 1;
    }
    if ((!err) && (out != NULL)) {
        /* Return through parameter too. */
        *out = rsa;
        /* Move buffer on by the used amount. */
        *derBuf += wolfssl_der_length(*derBuf, (int)derSz);
    }

    if (err) {
        /* Dispose of any created RSA key. */
        wolfSSL_RSA_free(rsa);
        rsa = NULL;
    }
    return rsa;
}

/* Converts an internal RSA structure to DER format for the private key.
 *
 * If "pp" is null then buffer size only is returned.
 * If "*pp" is null then a created buffer is set in *pp and the caller is
 *  responsible for free'ing it.
 *
 * @param [in]      rsa  RSA key.
 * @param [in, out] pp   On in, pointer to allocated buffer or NULL.
 *                       May be NULL.
 *                       On out, newly allocated buffer or pointer to byte after
 *                       encoding in passed in buffer.
 *
 * @return  Size of DER encoding on success
 * @return  BAD_FUNC_ARG when rsa is NULL.
 * @return  0 on failure.
 */
int wolfSSL_i2d_RSAPrivateKey(WOLFSSL_RSA *rsa, unsigned char **pp)
{
    int ret;

    WOLFSSL_ENTER("wolfSSL_i2d_RSAPrivateKey");

    /* Validate parameters. */
    if (rsa == NULL) {
        WOLFSSL_ERROR_MSG("Bad Function Arguments");
        ret = BAD_FUNC_ARG;
    }
    /* Encode the RSA key as a DER. Call allocates buffer into pp.
     * No heap hint as this gets returned to the user */
    else if ((ret = wolfSSL_RSA_To_Der_ex(rsa, pp, 0, NULL)) < 0) {
        WOLFSSL_ERROR_MSG("wolfSSL_RSA_To_Der failed");
        ret = 0;
    }

    /* Size of DER encoding. */
    return ret;
}

/* Converts an internal RSA structure to DER format for the public key.
 *
 * If "pp" is null then buffer size only is returned.
 * If "*pp" is null then a created buffer is set in *pp and the caller is
 *  responsible for free'ing it.
 *
 * @param [in]      rsa  RSA key.
 * @param [in, out] pp   On in, pointer to allocated buffer or NULL.
 *                       May be NULL.
 *                       On out, newly allocated buffer or pointer to byte after
 *                       encoding in passed in buffer.
 * @return  Size of DER encoding on success
 * @return  BAD_FUNC_ARG when rsa is NULL.
 * @return  0 on failure.
 */
int wolfSSL_i2d_RSAPublicKey(WOLFSSL_RSA *rsa, unsigned char **pp)
{
    int ret;

    WOLFSSL_ENTER("wolfSSL_i2d_RSAPublicKey");

    /* check for bad functions arguments */
    if (rsa == NULL) {
        WOLFSSL_ERROR_MSG("Bad Function Arguments");
        ret = BAD_FUNC_ARG;
    }
    /* Encode the RSA key as a DER. Call allocates buffer into pp.
     * No heap hint as this gets returned to the user */
    else if ((ret = wolfSSL_RSA_To_Der_ex(rsa, pp, 1, NULL)) < 0) {
        WOLFSSL_ERROR_MSG("wolfSSL_RSA_To_Der failed");
        ret = 0;
    }

    return ret;
}

#endif /* OPENSSL_EXTRA */

/*
 * RSA to/from BIO APIs
 */

/* wolfSSL_d2i_RSAPublicKey_bio not supported */

#if defined(OPENSSL_ALL) || defined(WOLFSSL_ASIO) || defined(WOLFSSL_HAPROXY) \
    || defined(WOLFSSL_NGINX) || defined(WOLFSSL_QT)

#if defined(WOLFSSL_KEY_GEN) && !defined(NO_BIO)

/* Read DER data from a BIO.
 *
 * DER structures start with a constructed sequence. Use this to calculate the
 * total length of the DER data.
 *
 * @param [in]  bio   BIO object to read from.
 * @param [out] out   Buffer holding DER encoding.
 * @return  Number of bytes to DER encoding on success.
 * @return  0 on failure.
 */
static int wolfssl_read_der_bio(WOLFSSL_BIO* bio, unsigned char** out)
{
    int err = 0;
    unsigned char seq[MAX_SEQ_SZ];
    unsigned char* der = NULL;
    int derLen = 0;

    /* Read in a minimal amount to get a SEQUENCE header of any size. */
    if (wolfSSL_BIO_read(bio, seq, sizeof(seq)) != sizeof(seq)) {
        WOLFSSL_ERROR_MSG("wolfSSL_BIO_read() of sequence failure");
        err = 1;
    }
    /* Calculate complete DER encoding length. */
    if ((!err) && ((derLen = wolfssl_der_length(seq, sizeof(seq))) <= 0)) {
        WOLFSSL_ERROR_MSG("DER SEQUENCE decode failed");
        err = 1;
    }
    /* Allocate a buffer to read DER data into. */
    if ((!err) && ((der = (unsigned char*)XMALLOC((size_t)derLen, bio->heap,
            DYNAMIC_TYPE_TMP_BUFFER)) == NULL)) {
        WOLFSSL_ERROR_MSG("Malloc failure");
        err = 1;
    }
    if (!err) {
        /* Calculate the unread amount. */
        int len = derLen - (int)sizeof(seq);
        /* Copy the previously read data into the buffer. */
        XMEMCPY(der, seq, sizeof(seq));
        /* Read rest of DER data from BIO. */
        if (wolfSSL_BIO_read(bio, der + sizeof(seq), len) != len) {
            WOLFSSL_ERROR_MSG("wolfSSL_BIO_read() failure");
            err = 1;
        }
    }
    if (!err) {
        /* Return buffer through parameter. */
        *out = der;
    }

    if (err) {
        /* Dispose of any allocated buffer on error. */
        XFREE(der, bio->heap, DYNAMIC_TYPE_TMP_BUFFER);
        derLen = 0;
    }
    return derLen;
}

/* Reads the RSA private key data from a BIO to the internal form.
 *
 * Creates new RSA key from the DER encoded RSA private key read from the BIO.
 *
 * @param [in]  bio  BIO object to read from.
 * @param [out] out  Pointer to RSA key to return through. May be NULL.
 * @return  RSA key on success.
 * @return  NULL on failure.
 */
WOLFSSL_RSA* wolfSSL_d2i_RSAPrivateKey_bio(WOLFSSL_BIO *bio, WOLFSSL_RSA **out)
{
    WOLFSSL_RSA* key = NULL;
    unsigned char* der = NULL;
    int derLen = 0;
    int err;

    WOLFSSL_ENTER("wolfSSL_d2i_RSAPrivateKey_bio");

    /* Validate parameters. */
    err = (bio == NULL);
    /* Read just DER encoding from BIO - buffer allocated in call. */
    if ((!err) && ((derLen = wolfssl_read_der_bio(bio, &der)) == 0)) {
        err = 1;
    }
    if (!err) {
        /* Keep der for call to deallocate. */
        const unsigned char* cder = der;
        /* Create an RSA key from the data from the BIO. */
        key = wolfSSL_d2i_RSAPrivateKey(NULL, &cder, derLen);
        err = (key == NULL);
    }
    if ((!err) && (out != NULL)) {
        /* Return the created RSA key through the parameter. */
        *out = key;
    }

    if (err) {
        /* Dispose of created key on error. */
        wolfSSL_RSA_free(key);
        key = NULL;
    }
    /* Dispose of allocated data. */
    XFREE(der, bio ? bio->heap : NULL, DYNAMIC_TYPE_TMP_BUFFER);
    return key;
}
#endif /* defined(WOLFSSL_KEY_GEN) && !NO_BIO */

#endif /* OPENSSL_ALL || WOLFSSL_ASIO || WOLFSSL_HAPROXY || WOLFSSL_QT */

/*
 * RSA DER APIs
 */

#ifdef OPENSSL_EXTRA

/* Create a DER encoding of key.
 *
 * Not OpenSSL API.
 *
 * @param [in]  rsa        RSA key.
 * @param [out] outBuf     Allocated buffer containing DER encoding.
 *                         May be NULL.
 * @param [in]  publicKey  Whether to encode as public key.
 * @param [in]  heap       Heap hint.
 * @return  Encoding size on success.
 * @return  Negative on failure.
 */
int wolfSSL_RSA_To_Der(WOLFSSL_RSA* rsa, byte** outBuf, int publicKey,
    void* heap)
{
    byte* p = NULL;
    int ret;

    if (outBuf != NULL) {
        p = *outBuf;
    }
    ret = wolfSSL_RSA_To_Der_ex(rsa, outBuf, publicKey, heap);
    if ((ret > 0) && (p != NULL)) {
        *outBuf = p;
    }
    return ret;
}

/* Create a DER encoding of key.
 *
 * Buffer allocated with heap and DYNAMIC_TYPE_TMP_BUFFER.
 *
 * @param [in]      rsa        RSA key.
 * @param [in, out] outBuf     On in, pointer to allocated buffer or NULL.
 *                             May be NULL.
 *                             On out, newly allocated buffer or pointer to byte
 *                             after encoding in passed in buffer.
 * @param [in]      publicKey  Whether to encode as public key.
 * @param [in]      heap       Heap hint.
 * @return  Encoding size on success.
 * @return  Negative on failure.
 */
static int wolfSSL_RSA_To_Der_ex(WOLFSSL_RSA* rsa, byte** outBuf, int publicKey,
    void* heap)
{
    int ret = 1;
    int derSz = 0;
    byte* derBuf = NULL;

    WOLFSSL_ENTER("wolfSSL_RSA_To_Der");

    /* Unused if memory is disabled. */
    (void)heap;

    /* Validate parameters. */
    if ((rsa == NULL) || ((publicKey != 0) && (publicKey != 1))) {
        WOLFSSL_LEAVE("wolfSSL_RSA_To_Der", BAD_FUNC_ARG);
        ret = BAD_FUNC_ARG;
    }
    /* Push external RSA data into internal RSA key if not set. */
    if ((ret == 1) && (!rsa->inSet)) {
        ret = SetRsaInternal(rsa);
    }
    /* wc_RsaKeyToPublicDer encode regardless of values. */
    if ((ret == 1) && publicKey && (mp_iszero(&((RsaKey*)rsa->internal)->n) ||
            mp_iszero(&((RsaKey*)rsa->internal)->e))) {
        ret = BAD_FUNC_ARG;
    }

    if (ret == 1) {
        if (publicKey) {
            /* Calculate length of DER encoded RSA public key. */
            derSz = wc_RsaPublicKeyDerSize((RsaKey*)rsa->internal, 1);
            if (derSz < 0) {
                WOLFSSL_ERROR_MSG("wc_RsaPublicKeyDerSize failed");
                ret = derSz;
            }
        }
        else {
            /* Calculate length of DER encoded RSA private key. */
            derSz = wc_RsaKeyToDer((RsaKey*)rsa->internal, NULL, 0);
            if (derSz < 0) {
                WOLFSSL_ERROR_MSG("wc_RsaKeyToDer failed");
                ret = derSz;
            }
        }
    }

    if ((ret == 1) && (outBuf != NULL)) {
        derBuf = *outBuf;
        if (derBuf == NULL) {
            /* Allocate buffer to hold DER encoded RSA key. */
            derBuf = (byte*)XMALLOC((size_t)derSz, heap,
                DYNAMIC_TYPE_TMP_BUFFER);
            if (derBuf == NULL) {
                WOLFSSL_ERROR_MSG("Memory allocation failed");
                ret = MEMORY_ERROR;
            }
        }
    }
    if ((ret == 1) && (outBuf != NULL)) {
        if (publicKey > 0) {
            /* RSA public key to DER. */
            derSz = wc_RsaKeyToPublicDer((RsaKey*)rsa->internal, derBuf,
                (word32)derSz);
        }
        else {
            /* RSA private key to DER. */
            derSz = wc_RsaKeyToDer((RsaKey*)rsa->internal, derBuf,
                (word32)derSz);
        }
        if (derSz < 0) {
            WOLFSSL_ERROR_MSG("RSA key encoding failed");
            ret = derSz;
        }
        else if ((*outBuf) != NULL) {
            derBuf = NULL;
            *outBuf += derSz;
        }
        else {
            /* Return allocated buffer. */
            *outBuf = derBuf;
        }
    }
    if (ret == 1) {
        /* Success - return DER encoding size. */
        ret = derSz;
    }

    if ((outBuf != NULL) && (*outBuf != derBuf)) {
        /* Not returning buffer, needs to be disposed of. */
        XFREE(derBuf, heap, DYNAMIC_TYPE_TMP_BUFFER);
    }
    WOLFSSL_LEAVE("wolfSSL_RSA_To_Der", ret);
    return ret;
}

#endif /* OPENSSL_EXTRA */

#if defined(OPENSSL_EXTRA) || defined(OPENSSL_EXTRA_X509_SMALL)
/* Load the DER encoded private RSA key.
 *
 * Not OpenSSL API.
 *
 * @param [in] rsa     RSA key.
 * @param [in] derBuf  Buffer holding DER encoding.
 * @param [in] derSz   Length of DER encoding.
 * @return  1 on success.
 * @return  -1 on failure.
 */
int wolfSSL_RSA_LoadDer(WOLFSSL_RSA* rsa, const unsigned char* derBuf,
    int derSz)
{
    /* Call implementation that handles both private and public keys. */
    return wolfSSL_RSA_LoadDer_ex(rsa, derBuf, derSz, WOLFSSL_RSA_LOAD_PRIVATE);
}

/* Load the DER encoded public or private RSA key.
 *
 * Not OpenSSL API.
 *
 * @param [in] rsa     RSA key.
 * @param [in] derBuf  Buffer holding DER encoding.
 * @param [in] derSz   Length of DER encoding.
 * @param [in] opt     Indicates public or private key.
 *                     (WOLFSSL_RSA_LOAD_PUBLIC or WOLFSSL_RSA_LOAD_PRIVATE)
 * @return  1 on success.
 * @return  -1 on failure.
 */
int wolfSSL_RSA_LoadDer_ex(WOLFSSL_RSA* rsa, const unsigned char* derBuf,
    int derSz, int opt)
{
    int ret = 1;
    int res;
    word32 idx = 0;
    word32 algId;

    WOLFSSL_ENTER("wolfSSL_RSA_LoadDer");

    /* Validate parameters. */
    if ((rsa == NULL) || (rsa->internal == NULL) || (derBuf == NULL) ||
            (derSz <= 0)) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = -1;
    }

    if (ret == 1) {
        rsa->pkcs8HeaderSz = 0;
        /* Check if input buffer has PKCS8 header. In the case that it does not
         * have a PKCS8 header then do not error out. */
        res = ToTraditionalInline_ex((const byte*)derBuf, &idx, (word32)derSz,
            &algId);
        if (res > 0) {
            /* Store size of PKCS#8 header for encoding. */
            WOLFSSL_MSG("Found PKCS8 header");
            rsa->pkcs8HeaderSz = (word16)idx;
        }
        /* When decoding and not PKCS#8, return will be ASN_PARSE_E. */
        else if (res != WC_NO_ERR_TRACE(ASN_PARSE_E)) {
            /* Something went wrong while decoding. */
            WOLFSSL_ERROR_MSG("Unexpected error with trying to remove PKCS#8 "
                              "header");
            ret = -1;
        }
    }
    if (ret == 1) {
        /* Decode private or public key data. */
        if (opt == WOLFSSL_RSA_LOAD_PRIVATE) {
            res = wc_RsaPrivateKeyDecode(derBuf, &idx, (RsaKey*)rsa->internal,
                (word32)derSz);
        }
        else {
            res = wc_RsaPublicKeyDecode(derBuf, &idx, (RsaKey*)rsa->internal,
                (word32)derSz);
        }
        /* Check for error. */
        if (res < 0) {
            if (opt == WOLFSSL_RSA_LOAD_PRIVATE) {
                 WOLFSSL_ERROR_MSG("RsaPrivateKeyDecode failed");
            }
            else {
                 WOLFSSL_ERROR_MSG("RsaPublicKeyDecode failed");
            }
            WOLFSSL_ERROR_VERBOSE(res);
            ret = -1;
        }
    }
    if (ret == 1) {
        /* Set external RSA key data from wolfCrypt key. */
        if (SetRsaExternal(rsa) != 1) {
            ret = -1;
        }
        else {
            rsa->inSet = 1;
        }
    }

    return ret;
}

#endif /* OPENSSL_EXTRA || OPENSSL_EXTRA_X509_SMALL */

#if defined(OPENSSL_EXTRA) || defined(WOLFSSL_WPAS_SMALL)

#if !defined(NO_BIO) || !defined(NO_FILESYSTEM)
/* Load DER encoded data into WOLFSSL_RSA object.
 *
 * Creates a new WOLFSSL_RSA object if one is not passed in.
 *
 * @param [in, out] rsa   WOLFSSL_RSA object to load into.
 *                        When rsa or *rsa is NULL a new object is created.
 *                        When not NULL and *rsa is NULL then new object
 *                        returned through pointer.
 * @param [in]      in    DER encoded RSA key data.
 * @param [in]      inSz  Size of DER encoded data in bytes.
 * @param [in]      opt   Public or private key encoded in data. Valid values:
 *                        WOLFSSL_RSA_LOAD_PRIVATE, WOLFSSL_RSA_LOAD_PUBLIC.
 * @return  NULL on failure.
 * @return  WOLFSSL_RSA object on success.
 */
static WOLFSSL_RSA* wolfssl_rsa_d2i(WOLFSSL_RSA** rsa, const unsigned char* in,
    long inSz, int opt)
{
    WOLFSSL_RSA* ret = NULL;

    if ((rsa != NULL) && (*rsa != NULL)) {
        ret = *rsa;
    }
    else {
        ret = wolfSSL_RSA_new();
    }
    if ((ret != NULL) && (wolfSSL_RSA_LoadDer_ex(ret, in, (int)inSz, opt)
            != 1)) {
        if ((rsa == NULL) || (ret != *rsa)) {
            wolfSSL_RSA_free(ret);
        }
        ret = NULL;
    }

    if ((rsa != NULL) && (*rsa == NULL)) {
        *rsa = ret;
    }
    return ret;
}
#endif

#endif /* OPENSSL_EXTRA || WOLFSSL_WPAS_SMALL */

/*
 * RSA PEM APIs
 */

#ifdef OPENSSL_EXTRA

#ifndef NO_BIO
#if defined(WOLFSSL_KEY_GEN)
/* Writes PEM encoding of an RSA public key to a BIO.
 *
 * @param [in] bio  BIO object to write to.
 * @param [in] rsa  RSA key to write.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_PEM_write_bio_RSA_PUBKEY(WOLFSSL_BIO* bio, WOLFSSL_RSA* rsa)
{
    int ret = 1;
    int derSz = 0;
    byte* derBuf = NULL;

    WOLFSSL_ENTER("wolfSSL_PEM_write_bio_RSA_PUBKEY");

    /* Validate parameters. */
    if ((bio == NULL) || (rsa == NULL)) {
        WOLFSSL_ERROR_MSG("Bad Function Arguments");
        return 0;
    }

    if ((derSz = wolfSSL_RSA_To_Der(rsa, &derBuf, 1, bio->heap)) < 0) {
        WOLFSSL_ERROR_MSG("wolfSSL_RSA_To_Der failed");
        ret = 0;
    }
    if (derBuf == NULL) {
        WOLFSSL_ERROR_MSG("wolfSSL_RSA_To_Der failed to get buffer");
        ret = 0;
    }
    if ((ret == 1) && (der_write_to_bio_as_pem(derBuf, derSz, bio,
            PUBLICKEY_TYPE) != 1)) {
        ret = 0;
    }

    /* Dispose of DER buffer. */
    XFREE(derBuf, bio->heap, DYNAMIC_TYPE_TMP_BUFFER);
    return ret;
}

#endif /* WOLFSSL_KEY_GEN */
#endif /* !NO_BIO */

#if defined(WOLFSSL_KEY_GEN)
#ifndef NO_FILESYSTEM

/* Writes PEM encoding of an RSA public key to a file pointer.
 *
 * @param [in] fp    File pointer to write to.
 * @param [in] rsa   RSA key to write.
 * @param [in] type  PEM type to write out.
 * @return  1 on success.
 * @return  0 on failure.
 */
static int wolfssl_pem_write_rsa_public_key(XFILE fp, WOLFSSL_RSA* rsa,
    int type)
{
    int ret = 1;
    int derSz;
    byte* derBuf = NULL;

    /* Validate parameters. */
    if ((fp == XBADFILE) || (rsa == NULL)) {
        WOLFSSL_ERROR_MSG("Bad Function Arguments");
        return 0;
    }

    if ((derSz = wolfSSL_RSA_To_Der(rsa, &derBuf, 1, rsa->heap)) < 0) {
        WOLFSSL_ERROR_MSG("wolfSSL_RSA_To_Der failed");
        ret = 0;
    }
    if (derBuf == NULL) {
        WOLFSSL_ERROR_MSG("wolfSSL_RSA_To_Der failed to get buffer");
        ret = 0;
    }
    if ((ret == 1) && (der_write_to_file_as_pem(derBuf, derSz, fp, type,
            rsa->heap) != 1)) {
        ret = 0;
    }

    /* Dispose of DER buffer. */
    XFREE(derBuf, rsa->heap, DYNAMIC_TYPE_TMP_BUFFER);

    return ret;
}

/* Writes PEM encoding of an RSA public key to a file pointer.
 *
 * Header/footer will contain: PUBLIC KEY
 *
 * @param [in] fp   File pointer to write to.
 * @param [in] rsa  RSA key to write.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_PEM_write_RSA_PUBKEY(XFILE fp, WOLFSSL_RSA* rsa)
{
    return wolfssl_pem_write_rsa_public_key(fp, rsa, PUBLICKEY_TYPE);
}

/* Writes PEM encoding of an RSA public key to a file pointer.
 *
 * Header/footer will contain: RSA PUBLIC KEY
 *
 * @param [in] fp   File pointer to write to.
 * @param [in] rsa  RSA key to write.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_PEM_write_RSAPublicKey(XFILE fp, WOLFSSL_RSA* rsa)
{
    return wolfssl_pem_write_rsa_public_key(fp, rsa, RSA_PUBLICKEY_TYPE);
}
#endif /* !NO_FILESYSTEM */
#endif /* WOLFSSL_KEY_GEN */

#ifndef NO_BIO
/* Create an RSA public key by reading the PEM encoded data from the BIO.
 *
 * @param [in]  bio   BIO object to read from.
 * @param [out] out   RSA key created.
 * @param [in]  cb    Password callback when PEM encrypted.
 * @param [in]  pass  NUL terminated string for passphrase when PEM encrypted.
 * @return  RSA key on success.
 * @return  NULL on failure.
 */
WOLFSSL_RSA *wolfSSL_PEM_read_bio_RSA_PUBKEY(WOLFSSL_BIO* bio,
    WOLFSSL_RSA** out, wc_pem_password_cb* cb, void *pass)
{
    WOLFSSL_RSA* rsa = NULL;
    DerBuffer*   der = NULL;
    int          keyFormat = 0;

    WOLFSSL_ENTER("wolfSSL_PEM_read_bio_RSA_PUBKEY");

    if ((bio != NULL) && (pem_read_bio_key(bio, cb, pass, PUBLICKEY_TYPE,
            &keyFormat, &der) >= 0)) {
        rsa = wolfssl_rsa_d2i(out, der->buffer, der->length,
            WOLFSSL_RSA_LOAD_PUBLIC);
        if (rsa == NULL) {
            WOLFSSL_ERROR_MSG("Error loading DER buffer into WOLFSSL_RSA");
        }
    }

    FreeDer(&der);
    if ((out != NULL) && (rsa != NULL)) {
        *out = rsa;
    }
    return rsa;
}
#endif /* !NO_BIO */

#ifndef NO_FILESYSTEM
/* Create an RSA public key by reading the PEM encoded data from the BIO.
 *
 * Header/footer should contain: PUBLIC KEY
 * PEM decoder supports either 'RSA PUBLIC KEY' or 'PUBLIC KEY'.
 *
 * @param [in]  fp    File pointer to read from.
 * @param [out] out   RSA key created.
 * @param [in]  cb    Password callback when PEM encrypted.
 * @param [in]  pass  NUL terminated string for passphrase when PEM encrypted.
 * @return  RSA key on success.
 * @return  NULL on failure.
 */
WOLFSSL_RSA *wolfSSL_PEM_read_RSA_PUBKEY(XFILE fp,
    WOLFSSL_RSA** out, wc_pem_password_cb* cb, void *pass)
{
    WOLFSSL_RSA* rsa = NULL;
    DerBuffer*   der = NULL;
    int          keyFormat = 0;

    WOLFSSL_ENTER("wolfSSL_PEM_read_RSA_PUBKEY");

    if ((fp != XBADFILE) && (pem_read_file_key(fp, cb, pass, PUBLICKEY_TYPE,
            &keyFormat, &der) >= 0)) {
        rsa = wolfssl_rsa_d2i(out, der->buffer, der->length,
            WOLFSSL_RSA_LOAD_PUBLIC);
        if (rsa == NULL) {
            WOLFSSL_ERROR_MSG("Error loading DER buffer into WOLFSSL_RSA");
        }
    }

    FreeDer(&der);
    if ((out != NULL) && (rsa != NULL)) {
        *out = rsa;
    }
    return rsa;
}

/* Create an RSA public key by reading the PEM encoded data from the BIO.
 *
 * Header/footer should contain: RSA PUBLIC KEY
 * PEM decoder supports either 'RSA PUBLIC KEY' or 'PUBLIC KEY'.
 *
 * @param [in]  fp    File pointer to read from.
 * @param [out] rsa   RSA key created.
 * @param [in]  cb    Password callback when PEM encrypted. May be NULL.
 * @param [in]  pass  NUL terminated string for passphrase when PEM encrypted.
 *                    May be NULL.
 * @return  RSA key on success.
 * @return  NULL on failure.
 */
WOLFSSL_RSA* wolfSSL_PEM_read_RSAPublicKey(XFILE fp, WOLFSSL_RSA** rsa,
    wc_pem_password_cb* cb, void* pass)
{
    return wolfSSL_PEM_read_RSA_PUBKEY(fp, rsa, cb, pass);
}

#endif /* NO_FILESYSTEM */

#if defined(WOLFSSL_KEY_GEN) && \
    (defined(WOLFSSL_PEM_TO_DER) || defined(WOLFSSL_DER_TO_PEM))

/* Writes PEM encoding of an RSA private key to newly allocated buffer.
 *
 * Buffer returned was allocated with: DYNAMIC_TYPE_KEY.
 *
 * @param [in]  rsa       RSA key to write.
 * @param [in]  cipher    Cipher to use when PEM encrypted. May be NULL.
 * @param [in]  passwd    Password string when PEM encrypted. May be NULL.
 * @param [in]  passwdSz  Length of password string when PEM encrypted.
 * @param [out] pem       Allocated buffer with PEM encoding.
 * @param [out] pLen      Length of PEM encoding.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_PEM_write_mem_RSAPrivateKey(RSA* rsa, const EVP_CIPHER* cipher,
    unsigned char* passwd, int passwdSz, unsigned char **pem, int *pLen)
{
    int ret = 1;
    byte* derBuf = NULL;
    int  derSz = 0;

    WOLFSSL_ENTER("wolfSSL_PEM_write_mem_RSAPrivateKey");

    /* Validate parameters. */
    if ((pem == NULL) || (pLen == NULL) || (rsa == NULL) ||
            (rsa->internal == NULL)) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = 0;
    }

    /* Set the RSA key data into the wolfCrypt RSA key if not done so. */
    if ((ret == 1) && (!rsa->inSet) && (SetRsaInternal(rsa) != 1)) {
        ret = 0;
    }

    /* Encode wolfCrypt RSA key to DER - derBuf allocated in call. */
    if ((ret == 1) && ((derSz = wolfSSL_RSA_To_Der(rsa, &derBuf, 0,
            rsa->heap)) < 0)) {
        WOLFSSL_ERROR_MSG("wolfSSL_RSA_To_Der failed");
        ret = 0;
    }

    if ((ret == 1) && (der_to_enc_pem_alloc(derBuf, derSz, cipher, passwd,
            passwdSz, PRIVATEKEY_TYPE, NULL, pem, pLen) != 1)) {
        WOLFSSL_ERROR_MSG("der_to_enc_pem_alloc failed");
        ret = 0;
    }

    return ret;
}

#ifndef NO_BIO
/* Writes PEM encoding of an RSA private key to a BIO.
 *
 * @param [in] bio     BIO object to write to.
 * @param [in] rsa     RSA key to write.
 * @param [in] cipher  Cipher to use when PEM encrypted.
 * @param [in] passwd  Password string when PEM encrypted.
 * @param [in] len     Length of password string when PEM encrypted.
 * @param [in] cb      Password callback to use when PEM encrypted.
 * @param [in] arg     NUL terminated string for passphrase when PEM encrypted.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_PEM_write_bio_RSAPrivateKey(WOLFSSL_BIO* bio, WOLFSSL_RSA* rsa,
    const WOLFSSL_EVP_CIPHER* cipher, unsigned char* passwd, int len,
    wc_pem_password_cb* cb, void* arg)
{
    int ret = 1;
    byte* pem = NULL;
    int pLen = 0;

    (void)cb;
    (void)arg;

    WOLFSSL_ENTER("wolfSSL_PEM_write_bio_RSAPrivateKey");

    /* Validate parameters. */
    if ((bio == NULL) || (rsa == NULL) || (rsa->internal == NULL)) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = 0;
    }

    if (ret == 1) {
        /* Write PEM to buffer that is allocated in the call. */
        ret = wolfSSL_PEM_write_mem_RSAPrivateKey(rsa, cipher, passwd, len,
            &pem, &pLen);
        if (ret != 1) {
            WOLFSSL_ERROR_MSG("wolfSSL_PEM_write_mem_RSAPrivateKey failed");
        }
    }
    /* Write PEM to BIO. */
    if ((ret == 1) && (wolfSSL_BIO_write(bio, pem, pLen) <= 0)) {
        WOLFSSL_ERROR_MSG("RSA private key BIO write failed");
        ret = 0;
    }

    /* Dispose of any allocated PEM buffer. */
    XFREE(pem, NULL, DYNAMIC_TYPE_KEY);
    return ret;
}
#endif /* !NO_BIO */

#ifndef NO_FILESYSTEM
/* Writes PEM encoding of an RSA private key to a file pointer.
 *
 * TODO: Support use of the password callback and callback context.
 *
 * @param [in] fp        File pointer to write to.
 * @param [in] rsa       RSA key to write.
 * @param [in] cipher    Cipher to use when PEM encrypted. May be NULL.
 * @param [in] passwd    Password string when PEM encrypted. May be NULL.
 * @param [in] passwdSz  Length of password string when PEM encrypted.
 * @param [in] cb        Password callback to use when PEM encrypted. Unused.
 * @param [in] arg       NUL terminated string for passphrase when PEM
 *                       encrypted. Unused.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_PEM_write_RSAPrivateKey(XFILE fp, WOLFSSL_RSA *rsa,
    const EVP_CIPHER *cipher, unsigned char *passwd, int passwdSz,
    wc_pem_password_cb *cb, void *arg)
{
    int ret = 1;
    byte* pem = NULL;
    int pLen = 0;

    (void)cb;
    (void)arg;

    WOLFSSL_ENTER("wolfSSL_PEM_write_RSAPrivateKey");

    /* Validate parameters. */
    if ((fp == XBADFILE) || (rsa == NULL) || (rsa->internal == NULL)) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = 0;
    }

    if (ret == 1) {
        /* Write PEM to buffer that is allocated in the call. */
        ret = wolfSSL_PEM_write_mem_RSAPrivateKey(rsa, cipher, passwd, passwdSz,
            &pem, &pLen);
        if (ret != 1) {
            WOLFSSL_ERROR_MSG("wolfSSL_PEM_write_mem_RSAPrivateKey failed");
        }
    }
    /* Write PEM to file pointer. */
    if ((ret == 1) && ((int)XFWRITE(pem, 1, (size_t)pLen, fp) != pLen)) {
        WOLFSSL_ERROR_MSG("RSA private key file write failed");
        ret = 0;
    }

    /* Dispose of any allocated PEM buffer. */
    XFREE(pem, NULL, DYNAMIC_TYPE_KEY);
    return ret;
}
#endif /* NO_FILESYSTEM */
#endif /* WOLFSSL_KEY_GEN && WOLFSSL_PEM_TO_DER */

#ifndef NO_BIO
/* Create an RSA private key by reading the PEM encoded data from the BIO.
 *
 * @param [in]  bio   BIO object to read from.
 * @param [out] out   RSA key created.
 * @param [in]  cb    Password callback when PEM encrypted.
 * @param [in]  pass  NUL terminated string for passphrase when PEM encrypted.
 * @return  RSA key on success.
 * @return  NULL on failure.
 */
WOLFSSL_RSA* wolfSSL_PEM_read_bio_RSAPrivateKey(WOLFSSL_BIO* bio,
    WOLFSSL_RSA** out, wc_pem_password_cb* cb, void* pass)
{
    WOLFSSL_RSA* rsa = NULL;
    DerBuffer*   der = NULL;
    int          keyFormat = 0;

    WOLFSSL_ENTER("wolfSSL_PEM_read_bio_RSAPrivateKey");

    if ((bio != NULL) && (pem_read_bio_key(bio, cb, pass, PRIVATEKEY_TYPE,
            &keyFormat, &der) >= 0)) {
        rsa = wolfssl_rsa_d2i(out, der->buffer, der->length,
            WOLFSSL_RSA_LOAD_PRIVATE);
        if (rsa == NULL) {
            WOLFSSL_ERROR_MSG("Error loading DER buffer into WOLFSSL_RSA");
        }
    }

    FreeDer(&der);
    if ((out != NULL) && (rsa != NULL)) {
        *out = rsa;
    }
    return rsa;
}
#endif /* !NO_BIO */

/* Create an RSA private key by reading the PEM encoded data from the file
 * pointer.
 *
 * @param [in]  fp    File pointer to read from.
 * @param [out] out   RSA key created.
 * @param [in]  cb    Password callback when PEM encrypted.
 * @param [in]  pass  NUL terminated string for passphrase when PEM encrypted.
 * @return  RSA key on success.
 * @return  NULL on failure.
 */
#ifndef NO_FILESYSTEM
WOLFSSL_RSA* wolfSSL_PEM_read_RSAPrivateKey(XFILE fp, WOLFSSL_RSA** out,
    wc_pem_password_cb* cb, void* pass)
{
    WOLFSSL_RSA* rsa = NULL;
    DerBuffer*   der = NULL;
    int          keyFormat = 0;

    WOLFSSL_ENTER("wolfSSL_PEM_read_RSAPrivateKey");

    if ((fp != XBADFILE) && (pem_read_file_key(fp, cb, pass, PRIVATEKEY_TYPE,
            &keyFormat, &der) >= 0)) {
        rsa = wolfssl_rsa_d2i(out, der->buffer, der->length,
            WOLFSSL_RSA_LOAD_PRIVATE);
        if (rsa == NULL) {
            WOLFSSL_ERROR_MSG("Error loading DER buffer into WOLFSSL_RSA");
        }
    }

    FreeDer(&der);
    if ((out != NULL) && (rsa != NULL)) {
        *out = rsa;
    }
    return rsa;
}
#endif /* !NO_FILESYSTEM */

/*
 * RSA print APIs
 */

#if defined(XFPRINTF) && !defined(NO_FILESYSTEM) && \
    !defined(NO_STDIO_FILESYSTEM)
/* Print an RSA key to a file pointer.
 *
 * @param [in] fp      File pointer to write to.
 * @param [in] rsa     RSA key to write.
 * @param [in] indent  Number of spaces to prepend to each line.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_RSA_print_fp(XFILE fp, WOLFSSL_RSA* rsa, int indent)
{
    int ret = 1;

    WOLFSSL_ENTER("wolfSSL_RSA_print_fp");

    /* Validate parameters. */
    if ((fp == XBADFILE) || (rsa == NULL)) {
        ret = 0;
    }

    /* Set the external data from the wolfCrypt RSA key if not done. */
    if ((ret == 1) && (!rsa->exSet)) {
        ret = SetRsaExternal(rsa);
    }

    /* Get the key size from modulus if available. */
    if ((ret == 1) && (rsa->n != NULL)) {
        int keySize = wolfSSL_BN_num_bits(rsa->n);
        if (keySize == 0) {
            ret = 0;
        }
        else {
            if (XFPRINTF(fp, "%*s", indent, "") < 0)
                ret = 0;
            else if (XFPRINTF(fp, "RSA Private-Key: (%d bit, 2 primes)\n",
                              keySize) < 0)
                ret = 0;
        }
    }
    /* Print out any components available. */
    if ((ret == 1) && (rsa->n != NULL)) {
        ret = pk_bn_field_print_fp(fp, indent, "modulus", rsa->n);
    }
    if ((ret == 1) && (rsa->d != NULL)) {
        ret = pk_bn_field_print_fp(fp, indent, "privateExponent", rsa->d);
    }
    if ((ret == 1) && (rsa->p != NULL)) {
        ret = pk_bn_field_print_fp(fp, indent, "prime1", rsa->p);
    }
    if ((ret == 1) && (rsa->q != NULL)) {
        ret = pk_bn_field_print_fp(fp, indent, "prime2", rsa->q);
    }
    if ((ret == 1) && (rsa->dmp1 != NULL)) {
        ret = pk_bn_field_print_fp(fp, indent, "exponent1", rsa->dmp1);
    }
    if ((ret == 1) && (rsa->dmq1 != NULL)) {
        ret = pk_bn_field_print_fp(fp, indent, "exponent2", rsa->dmq1);
    }
    if ((ret == 1) && (rsa->iqmp != NULL)) {
        ret = pk_bn_field_print_fp(fp, indent, "coefficient", rsa->iqmp);
    }

    WOLFSSL_LEAVE("wolfSSL_RSA_print_fp", ret);

    return ret;
}
#endif /* XFPRINTF && !NO_FILESYSTEM && !NO_STDIO_FILESYSTEM */

#if defined(XSNPRINTF) && !defined(NO_BIO)
/* snprintf() must be available */

/* Maximum size of a header line. */
#define RSA_PRINT_MAX_HEADER_LINE   PRINT_NUM_MAX_INDENT

/* Writes the human readable form of RSA to a BIO.
 *
 * @param [in] bio     BIO object to write to.
 * @param [in] rsa     RSA key to write.
 * @param [in] indent  Number of spaces before each line.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_RSA_print(WOLFSSL_BIO* bio, WOLFSSL_RSA* rsa, int indent)
{
    int ret = 1;
    int sz = 0;
    RsaKey* key = NULL;
    char line[RSA_PRINT_MAX_HEADER_LINE];
    int i = 0;
    mp_int *num = NULL;
    /* Header strings. */
    const char *name[] = {
        "Modulus:", "Exponent:", "PrivateExponent:", "Prime1:", "Prime2:",
        "Exponent1:", "Exponent2:", "Coefficient:"
    };

    WOLFSSL_ENTER("wolfSSL_RSA_print");

    /* Validate parameters. */
    if ((bio == NULL) || (rsa == NULL) || (indent > PRINT_NUM_MAX_INDENT)) {
        ret = -1;
    }

    if (ret == 1) {
        key = (RsaKey*)rsa->internal;

        /* Get size in bits of key for printing out. */
        sz = wolfSSL_RSA_bits(rsa);
        if (sz <= 0) {
            WOLFSSL_ERROR_MSG("Error getting RSA key size");
            ret = 0;
        }
    }
    if (ret == 1) {
        /* Print any indent spaces. */
        ret = wolfssl_print_indent(bio, line, sizeof(line), indent);
    }
    if (ret == 1) {
        /* Print header line. */
        int len = XSNPRINTF(line, sizeof(line), "\nRSA %s: (%d bit)\n",
            (!mp_iszero(&key->d)) ? "Private-Key" : "Public-Key", sz);
        if (len >= (int)sizeof(line)) {
            WOLFSSL_ERROR_MSG("Buffer overflow while formatting key preamble");
            ret = 0;
        }
        else {
            if (wolfSSL_BIO_write(bio, line, len) <= 0) {
                ret = 0;
            }
        }
    }

    for (i = 0; (ret == 1) && (i < RSA_INTS); i++) {
        /* Get mp_int for index. */
        switch (i) {
            case 0:
                /* Print out modulus */
                num = &key->n;
                break;
            case 1:
                num = &key->e;
                break;
            case 2:
                num = &key->d;
                break;
            case 3:
                num = &key->p;
                break;
            case 4:
                num = &key->q;
                break;
            case 5:
                num = &key->dP;
                break;
            case 6:
                num = &key->dQ;
                break;
            case 7:
                num = &key->u;
                break;
            default:
                WOLFSSL_ERROR_MSG("Bad index value");
        }

        if (i == 1) {
            /* Print exponent as a 32-bit value. */
            ret = wolfssl_print_value(bio, num, name[i], indent);
        }
        else if (!mp_iszero(num)) {
            /* Print name and MP integer. */
            ret = wolfssl_print_number(bio, num, name[i], indent);
        }
    }

    return ret;
}
#endif /* XSNPRINTF && !NO_BIO */

#endif /* OPENSSL_EXTRA */

/*
 * RSA get/set/test APIs
 */

#if defined(OPENSSL_EXTRA) || defined(OPENSSL_EXTRA_X509_SMALL)
/* Set RSA key data (external) from wolfCrypt RSA key (internal).
 *
 * @param [in, out] rsa  RSA key.
 * @return  1 on success.
 * @return  0 on failure.
 */
int SetRsaExternal(WOLFSSL_RSA* rsa)
{
    int ret = 1;

    WOLFSSL_ENTER("SetRsaExternal");

    /* Validate parameters. */
    if ((rsa == NULL) || (rsa->internal == NULL)) {
        WOLFSSL_ERROR_MSG("rsa key NULL error");
        ret = -1;
    }

    if (ret == 1) {
        RsaKey* key = (RsaKey*)rsa->internal;

        /* Copy modulus. */
        ret = wolfssl_bn_set_value(&rsa->n, &key->n);
        if (ret != 1) {
            WOLFSSL_ERROR_MSG("rsa n error");
        }
        if (ret == 1) {
            /* Copy public exponent. */
            ret = wolfssl_bn_set_value(&rsa->e, &key->e);
            if (ret != 1) {
                WOLFSSL_ERROR_MSG("rsa e error");
            }
        }

        if (key->type == RSA_PRIVATE) {
            if (ret == 1) {
                /* Copy private exponent. */
                ret = wolfssl_bn_set_value(&rsa->d, &key->d);
                if (ret != 1) {
                    WOLFSSL_ERROR_MSG("rsa d error");
                }
            }
            if (ret == 1) {
                /* Copy first prime. */
                ret = wolfssl_bn_set_value(&rsa->p, &key->p);
                if (ret != 1) {
                    WOLFSSL_ERROR_MSG("rsa p error");
                }
            }
            if (ret == 1) {
                /* Copy second prime. */
                ret = wolfssl_bn_set_value(&rsa->q, &key->q);
                if (ret != 1) {
                    WOLFSSL_ERROR_MSG("rsa q error");
                }
            }
        #ifndef RSA_LOW_MEM
            if (ret == 1) {
                /* Copy d mod p-1. */
                ret = wolfssl_bn_set_value(&rsa->dmp1, &key->dP);
                if (ret != 1) {
                    WOLFSSL_ERROR_MSG("rsa dP error");
                }
            }
            if (ret == 1) {
                /* Copy d mod q-1. */
                ret = wolfssl_bn_set_value(&rsa->dmq1, &key->dQ);
                if (ret != 1) {
                    WOLFSSL_ERROR_MSG("rsa dq error");
                }
            }
            if (ret == 1) {
                /* Copy 1/q mod p. */
                ret = wolfssl_bn_set_value(&rsa->iqmp, &key->u);
                if (ret != 1) {
                    WOLFSSL_ERROR_MSG("rsa u error");
                }
            }
        #endif /* !RSA_LOW_MEM */
        }
    }
    if (ret == 1) {
        /* External values set. */
        rsa->exSet = 1;
    }
    else {
        /* Return 0 on failure. */
        ret = 0;
    }

    return ret;
}
#endif /* (OPENSSL_EXTRA || OPENSSL_EXTRA_X509_SMALL) */

#ifdef OPENSSL_EXTRA

/* Set wolfCrypt RSA key data (internal) from RSA key (external).
 *
 * @param [in, out] rsa  RSA key.
 * @return  1 on success.
 * @return  0 on failure.
 */
int SetRsaInternal(WOLFSSL_RSA* rsa)
{
    int ret = 1;

    WOLFSSL_ENTER("SetRsaInternal");

    /* Validate parameters. */
    if ((rsa == NULL) || (rsa->internal == NULL)) {
        WOLFSSL_ERROR_MSG("rsa key NULL error");
        ret = -1;
    }

    if (ret == 1) {
        RsaKey* key = (RsaKey*)rsa->internal;

        /* Copy down modulus if available. */
        if ((rsa->n != NULL) && (wolfssl_bn_get_value(rsa->n, &key->n) != 1)) {
            WOLFSSL_ERROR_MSG("rsa n key error");
            ret = -1;
        }

        /* Copy down public exponent if available. */
        if ((ret == 1) && (rsa->e != NULL) &&
                (wolfssl_bn_get_value(rsa->e, &key->e) != 1)) {
            WOLFSSL_ERROR_MSG("rsa e key error");
            ret = -1;
        }

        /* Enough numbers for public key */
        key->type = RSA_PUBLIC;

        /* Copy down private exponent if available. */
        if ((ret == 1) && (rsa->d != NULL)) {
            if (wolfssl_bn_get_value(rsa->d, &key->d) != 1) {
                WOLFSSL_ERROR_MSG("rsa d key error");
                ret = -1;
            }
            else {
                /* Enough numbers for private key */
                key->type = RSA_PRIVATE;
           }
        }

        /* Copy down first prime if available. */
        if ((ret == 1) && (rsa->p != NULL) &&
                (wolfssl_bn_get_value(rsa->p, &key->p) != 1)) {
            WOLFSSL_ERROR_MSG("rsa p key error");
            ret = -1;
        }

        /* Copy down second prime if available. */
        if ((ret == 1) && (rsa->q != NULL) &&
                (wolfssl_bn_get_value(rsa->q, &key->q) != 1)) {
            WOLFSSL_ERROR_MSG("rsa q key error");
            ret = -1;
        }

    #ifndef RSA_LOW_MEM
        /* Copy down d mod p-1 if available. */
        if ((ret == 1) && (rsa->dmp1 != NULL) &&
                (wolfssl_bn_get_value(rsa->dmp1, &key->dP) != 1)) {
            WOLFSSL_ERROR_MSG("rsa dP key error");
            ret = -1;
        }

        /* Copy down d mod q-1 if available. */
        if ((ret == 1) && (rsa->dmq1 != NULL) &&
                (wolfssl_bn_get_value(rsa->dmq1, &key->dQ) != 1)) {
            WOLFSSL_ERROR_MSG("rsa dQ key error");
            ret = -1;
        }

        /* Copy down 1/q mod p if available. */
        if ((ret == 1) && (rsa->iqmp != NULL) &&
                (wolfssl_bn_get_value(rsa->iqmp, &key->u) != 1)) {
            WOLFSSL_ERROR_MSG("rsa u key error");
            ret = -1;
        }
    #endif /* !RSA_LOW_MEM */

        if (ret == 1) {
            /* All available numbers have been set down. */
            rsa->inSet = 1;
        }
    }

    return ret;
}

/* Set the RSA method into object.
 *
 * @param [in, out] rsa   RSA key.
 * @param [in]      meth  RSA method.
 * @return  1 always.
 */
int wolfSSL_RSA_set_method(WOLFSSL_RSA *rsa, WOLFSSL_RSA_METHOD *meth)
{
    if (rsa != NULL) {
        /* Store the method into object. */
        rsa->meth = meth;
        /* Copy over flags. */
        rsa->flags = meth->flags;
    }
    /* OpenSSL always assumes it will work. */
    return 1;
}

/* Get the RSA method from the RSA object.
 *
 * @param [in] rsa  RSA key.
 * @return  RSA method on success.
 * @return  NULL when RSA is NULL or no method set.
 */
const WOLFSSL_RSA_METHOD* wolfSSL_RSA_get_method(const WOLFSSL_RSA *rsa)
{
    return (rsa != NULL) ? rsa->meth : NULL;
}

/* Get the size in bytes of the RSA key.
 *
 * Return compliant with OpenSSL
 *
 * @param [in] rsa  RSA key.
 * @return  RSA modulus size in bytes.
 * @return  0 on error.
 */
int wolfSSL_RSA_size(const WOLFSSL_RSA* rsa)
{
    int ret = 0;

    WOLFSSL_ENTER("wolfSSL_RSA_size");

    if (rsa != NULL) {
        /* Make sure we have set the RSA values into wolfCrypt RSA key. */
        if (rsa->inSet || (SetRsaInternal((WOLFSSL_RSA*)rsa) == 1)) {
            /* Get key size in bytes using wolfCrypt RSA key. */
            ret = wc_RsaEncryptSize((RsaKey*)rsa->internal);
        }
    }

    return ret;
}

/* Get the size in bits of the RSA key.
 *
 * Uses external modulus field.
 *
 * @param [in] rsa  RSA key.
 * @return  RSA modulus size in bits.
 * @return  0 on error.
 */
int wolfSSL_RSA_bits(const WOLFSSL_RSA* rsa)
{
    int ret = 0;

    WOLFSSL_ENTER("wolfSSL_RSA_bits");

    if (rsa != NULL) {
        /* Get number of bits in external modulus. */
        ret = wolfSSL_BN_num_bits(rsa->n);
    }

    return ret;
}

/* Get the BN objects that are the Chinese-Remainder Theorem (CRT) parameters.
 *
 * Only for those that are not NULL parameters.
 *
 * @param [in]  rsa   RSA key.
 * @param [out] dmp1  BN that is d mod (p - 1). May be NULL.
 * @param [out] dmq1  BN that is d mod (q - 1). May be NULL.
 * @param [out] iqmp  BN that is 1/q mod p. May be NULL.
 */
void wolfSSL_RSA_get0_crt_params(const WOLFSSL_RSA *rsa,
    const WOLFSSL_BIGNUM **dmp1, const WOLFSSL_BIGNUM **dmq1,
    const WOLFSSL_BIGNUM **iqmp)
{
    WOLFSSL_ENTER("wolfSSL_RSA_get0_crt_params");

    /* For any parameters not NULL, return the BN from the key or NULL. */
    if (dmp1 != NULL) {
        *dmp1 = (rsa != NULL) ? rsa->dmp1 : NULL;
    }
    if (dmq1 != NULL) {
        *dmq1 = (rsa != NULL) ? rsa->dmq1 : NULL;
    }
    if (iqmp != NULL) {
        *iqmp = (rsa != NULL) ? rsa->iqmp : NULL;
    }
}

/* Set the BN objects that are the Chinese-Remainder Theorem (CRT) parameters
 * into RSA key.
 *
 * If CRT parameter is NULL then there must be one in the RSA key already.
 *
 * @param [in, out] rsa   RSA key.
 * @param [in]      dmp1  BN that is d mod (p - 1). May be NULL.
 * @param [in]      dmq1  BN that is d mod (q - 1). May be NULL.
 * @param [in]      iqmp  BN that is 1/q mod p. May be NULL.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_RSA_set0_crt_params(WOLFSSL_RSA *rsa, WOLFSSL_BIGNUM *dmp1,
                                WOLFSSL_BIGNUM *dmq1, WOLFSSL_BIGNUM *iqmp)
{
    int ret = 1;

    WOLFSSL_ENTER("wolfSSL_RSA_set0_crt_params");

    /* If a param is NULL in rsa then it must be non-NULL in the
     * corresponding user input. */
    if ((rsa == NULL) || ((rsa->dmp1 == NULL) && (dmp1 == NULL)) ||
            ((rsa->dmq1 == NULL) && (dmq1 == NULL)) ||
            ((rsa->iqmp == NULL) && (iqmp == NULL))) {
        WOLFSSL_ERROR_MSG("Bad parameters");
        ret = 0;
    }
    if (ret == 1) {
        /* Replace the BNs. */
        if (dmp1 != NULL) {
            wolfSSL_BN_clear_free(rsa->dmp1);
            rsa->dmp1 = dmp1;
        }
        if (dmq1 != NULL) {
            wolfSSL_BN_clear_free(rsa->dmq1);
            rsa->dmq1 = dmq1;
        }
        if (iqmp != NULL) {
            wolfSSL_BN_clear_free(rsa->iqmp);
            rsa->iqmp = iqmp;
        }

        /* Set the values into the wolfCrypt RSA key. */
        if (SetRsaInternal(rsa) != 1) {
            if (dmp1 != NULL) {
                rsa->dmp1 = NULL;
            }
            if (dmq1 != NULL) {
                rsa->dmq1 = NULL;
            }
            if (iqmp != NULL) {
                rsa->iqmp = NULL;
            }
            ret = 0;
        }
    }

    return ret;
}

/* Get the BN objects that are the factors of the RSA key (two primes p and q).
 *
 * @param [in]  rsa  RSA key.
 * @param [out] p    BN that is first prime. May be NULL.
 * @param [out] q    BN that is second prime. May be NULL.
 */
void wolfSSL_RSA_get0_factors(const WOLFSSL_RSA *rsa, const WOLFSSL_BIGNUM **p,
                              const WOLFSSL_BIGNUM **q)
{
    WOLFSSL_ENTER("wolfSSL_RSA_get0_factors");

    /* For any primes not NULL, return the BN from the key or NULL. */
    if (p != NULL) {
        *p = (rsa != NULL) ? rsa->p : NULL;
    }
    if (q != NULL) {
        *q = (rsa != NULL) ? rsa->q : NULL;
    }
}

/* Set the BN objects that are the factors of the RSA key (two primes p and q).
 *
 * If factor parameter is NULL then there must be one in the RSA key already.
 *
 * @param [in, out] rsa  RSA key.
 * @param [in]      p    BN that is first prime. May be NULL.
 * @param [in]      q    BN that is second prime. May be NULL.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_RSA_set0_factors(WOLFSSL_RSA *rsa, WOLFSSL_BIGNUM *p,
    WOLFSSL_BIGNUM *q)
{
    int ret = 1;

    WOLFSSL_ENTER("wolfSSL_RSA_set0_factors");

    /* If a param is null in r then it must be non-null in the
     * corresponding user input. */
    if (rsa == NULL || ((rsa->p == NULL) && (p == NULL)) ||
            ((rsa->q == NULL) && (q == NULL))) {
        WOLFSSL_ERROR_MSG("Bad parameters");
        ret = 0;
    }
    if (ret == 1) {
        /* Replace the BNs. */
        if (p != NULL) {
            wolfSSL_BN_clear_free(rsa->p);
            rsa->p = p;
        }
        if (q != NULL) {
            wolfSSL_BN_clear_free(rsa->q);
            rsa->q = q;
        }

        /* Set the values into the wolfCrypt RSA key. */
        if (SetRsaInternal(rsa) != 1) {
             if (p != NULL) {
                 rsa->p = NULL;
             }
             if (q != NULL) {
                 rsa->q = NULL;
             }
             ret = 0;
        }
    }

    return ret;
}

/* Get the BN objects for the basic key numbers of the RSA key (modulus, public
 * exponent, private exponent).
 *
 * @param [in]  rsa  RSA key.
 * @param [out] n    BN that is the modulus. May be NULL.
 * @param [out] e    BN that is the public exponent. May be NULL.
 * @param [out] d    BN that is the private exponent. May be NULL.
 */
void wolfSSL_RSA_get0_key(const WOLFSSL_RSA *rsa, const WOLFSSL_BIGNUM **n,
    const WOLFSSL_BIGNUM **e, const WOLFSSL_BIGNUM **d)
{
    WOLFSSL_ENTER("wolfSSL_RSA_get0_key");

    /* For any parameters not NULL, return the BN from the key or NULL. */
    if (n != NULL) {
        *n = (rsa != NULL) ? rsa->n : NULL;
    }
    if (e != NULL) {
        *e = (rsa != NULL) ? rsa->e : NULL;
    }
    if (d != NULL) {
        *d = (rsa != NULL) ? rsa->d : NULL;
    }
}

/* Set the BN objects for the basic key numbers into the RSA key (modulus,
 * public exponent, private exponent).
 *
 * If BN parameter is NULL then there must be one in the RSA key already.
 *
 * @param [in,out]  rsa  RSA key.
 * @param [in]      n    BN that is the modulus. May be NULL.
 * @param [in]      e    BN that is the public exponent. May be NULL.
 * @param [in]      d    BN that is the private exponent. May be NULL.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_RSA_set0_key(WOLFSSL_RSA *rsa, WOLFSSL_BIGNUM *n, WOLFSSL_BIGNUM *e,
     WOLFSSL_BIGNUM *d)
{
    int ret = 1;

    /* If the fields n and e in r are NULL, the corresponding input
     * parameters MUST be non-NULL for n and e.  d may be
     * left NULL (in case only the public key is used).
     */
    if ((rsa == NULL) || ((rsa->n == NULL) && (n == NULL)) ||
            ((rsa->e == NULL) && (e == NULL))) {
        ret = 0;
    }
    if (ret == 1) {
        /* Replace the BNs. */
        if (n != NULL) {
            wolfSSL_BN_free(rsa->n);
            rsa->n = n;
        }
        if (e != NULL) {
            wolfSSL_BN_free(rsa->e);
            rsa->e = e;
        }
        if (d != NULL) {
            /* Private key is sensitive data. */
            wolfSSL_BN_clear_free(rsa->d);
            rsa->d = d;
        }

        /* Set the values into the wolfCrypt RSA key. */
        if (SetRsaInternal(rsa) != 1) {
            if (n != NULL) {
                rsa->n = NULL;
            }
            if (e != NULL) {
                rsa->e = NULL;
            }
            if (d != NULL) {
                rsa->d = NULL;
            }
            ret = 0;
        }
    }

    return ret;
}

/* Get the flags of the RSA key.
 *
 * @param [in] rsa  RSA key.
 * @return  Flags set in RSA key on success.
 * @return  0 when RSA key is NULL.
 */
int wolfSSL_RSA_flags(const WOLFSSL_RSA *rsa)
{
    int ret = 0;

    /* Get flags from the RSA key if available. */
    if (rsa != NULL) {
        ret = rsa->flags;
    }

    return ret;
}

/* Set the flags into the RSA key.
 *
 * @param [in, out] rsa    RSA key.
 * @param [in]      flags  Flags to set.
 */
void wolfSSL_RSA_set_flags(WOLFSSL_RSA *rsa, int flags)
{
    /* Add the flags into RSA key if available. */
    if (rsa != NULL) {
        rsa->flags |= flags;
    }
}

/* Clear the flags in the RSA key.
 *
 * @param [in, out] rsa    RSA key.
 * @param [in]      flags  Flags to clear.
 */
void wolfSSL_RSA_clear_flags(WOLFSSL_RSA *rsa, int flags)
{
    /* Clear the flags passed in that are on the RSA key if available. */
    if (rsa != NULL) {
        rsa->flags &= ~flags;
    }
}

/* Test the flags in the RSA key.
 *
 * @param [in] rsa  RSA key.
 * @return  Matching flags of RSA key on success.
 * @return  0 when RSA key is NULL.
 */
int wolfSSL_RSA_test_flags(const WOLFSSL_RSA *rsa, int flags)
{
    /* Return the flags passed in that are set on the RSA key if available. */
    return (rsa != NULL) ?  (rsa->flags & flags) : 0;
}

/* Get the extra data, by index, associated with the RSA key.
 *
 * @param [in] rsa  RSA key.
 * @param [in] idx  Index of extra data.
 * @return  Extra data (anonymous type) on success.
 * @return  NULL on failure.
 */
void* wolfSSL_RSA_get_ex_data(const WOLFSSL_RSA *rsa, int idx)
{
    WOLFSSL_ENTER("wolfSSL_RSA_get_ex_data");

#ifdef HAVE_EX_DATA
    return (rsa == NULL) ? NULL :
        wolfSSL_CRYPTO_get_ex_data(&rsa->ex_data, idx);
#else
    (void)rsa;
    (void)idx;

    return NULL;
#endif
}

/* Set extra data against the RSA key at an index.
 *
 * @param [in, out] rsa   RSA key.
 * @param [in]      idx   Index set set extra data at.
 * @param [in]      data  Extra data of anonymous type.
 * @return 1 on success.
 * @return 0 on failure.
 */
int wolfSSL_RSA_set_ex_data(WOLFSSL_RSA *rsa, int idx, void *data)
{
    WOLFSSL_ENTER("wolfSSL_RSA_set_ex_data");

#ifdef HAVE_EX_DATA
    return (rsa == NULL) ? 0 :
        wolfSSL_CRYPTO_set_ex_data(&rsa->ex_data, idx, data);
#else
    (void)rsa;
    (void)idx;
    (void)data;

    return 0;
#endif
}

#ifdef HAVE_EX_DATA_CLEANUP_HOOKS
/* Set the extra data and cleanup callback against the RSA key at an index.
 *
 * Not OpenSSL API.
 *
 * @param [in, out] rsa     RSA key.
 * @param [in]      idx     Index set set extra data at.
 * @param [in]      data    Extra data of anonymous type.
 * @param [in]      freeCb  Callback function to free extra data.
 * @return 1 on success.
 * @return 0 on failure.
 */
int wolfSSL_RSA_set_ex_data_with_cleanup(WOLFSSL_RSA *rsa, int idx, void *data,
    wolfSSL_ex_data_cleanup_routine_t freeCb)
{
    WOLFSSL_ENTER("wolfSSL_RSA_set_ex_data_with_cleanup");

    return (rsa == NULL) ? 0 :
        wolfSSL_CRYPTO_set_ex_data_with_cleanup(&rsa->ex_data, idx, data,
            freeCb);
}
#endif /* HAVE_EX_DATA_CLEANUP_HOOKS */

/*
 * RSA check key APIs
 */

#ifdef WOLFSSL_RSA_KEY_CHECK
/* Check that the RSA key is valid using wolfCrypt.
 *
 * @param [in] rsa  RSA key.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_RSA_check_key(const WOLFSSL_RSA* rsa)
{
    int ret = 1;

    WOLFSSL_ENTER("wolfSSL_RSA_check_key");

    /* Validate parameters. */
    if ((rsa == NULL) || (rsa->internal == NULL)) {
        ret = 0;
    }

    /* Constant RSA - assume internal data has been set. */

    /* Check wolfCrypt RSA key. */
    if ((ret == 1) && (wc_CheckRsaKey((RsaKey*)rsa->internal) != 0)) {
        ret = 0;
    }

    WOLFSSL_LEAVE("wolfSSL_RSA_check_key", ret);

    return ret;
}
#endif /* WOLFSSL_RSA_KEY_CHECK */

/*
 * RSA generate APIs
 */

/* Get a random number generator associated with the RSA key.
 *
 * If not able, then get the global if possible.
 * *tmpRng must not be an initialized RNG.
 * *tmpRng is allocated when WOLFSSL_SMALL_STACK is defined and an RNG isn't
 * associated with the wolfCrypt RSA key.
 *
 * @param [in]  rsa         RSA key.
 * @param [out] tmpRng      Temporary random number generator.
 * @param [out] initTmpRng  Temporary random number generator was initialized.
 *
 * @return  A wolfCrypt RNG to use on success.
 * @return  NULL on error.
 */
WC_RNG* WOLFSSL_RSA_GetRNG(WOLFSSL_RSA* rsa, WC_RNG** tmpRng, int* initTmpRng)
{
    WC_RNG* rng = NULL;
    int err = 0;

    /* Check validity of parameters. */
    if ((rsa == NULL) || (initTmpRng == NULL)) {
        err = 1;
    }
    if (!err) {
        /* Haven't initialized any RNG passed through tmpRng. */
        *initTmpRng = 0;

    #if !defined(HAVE_FIPS) && defined(WC_RSA_BLINDING)
        /* Use wolfCrypt RSA key's RNG if available/set. */
        rng = ((RsaKey*)rsa->internal)->rng;
    #endif
    }
    if ((!err) && (rng == NULL) && (tmpRng != NULL)) {
        /* Make an RNG with tmpRng or get global. */
        rng = wolfssl_make_rng(*tmpRng, initTmpRng);
        if ((rng != NULL) && *initTmpRng) {
            *tmpRng = rng;
        }
    }

    return rng;
}

/* Use the wolfCrypt RSA APIs to generate a new RSA key.
 *
 * @param [in, out] rsa   RSA key.
 * @param [in]      bits  Number of bits that the modulus must have.
 * @param [in]      e     A BN object holding the public exponent to use.
 * @param [in]      cb    Status callback. Unused.
 * @return 0 on success.
 * @return wolfSSL native error code on error.
 */
static int wolfssl_rsa_generate_key_native(WOLFSSL_RSA* rsa, int bits,
    WOLFSSL_BIGNUM* e, void* cb)
{
#ifdef WOLFSSL_KEY_GEN
    int ret = 0;
#ifdef WOLFSSL_SMALL_STACK
    WC_RNG* tmpRng = NULL;
#else
    WC_RNG  _tmpRng[1];
    WC_RNG* tmpRng = _tmpRng;
#endif
    int initTmpRng = 0;
    WC_RNG* rng = NULL;
#endif

    (void)cb;

    WOLFSSL_ENTER("wolfssl_rsa_generate_key_native");

#ifdef WOLFSSL_KEY_GEN
    /* Get RNG in wolfCrypt RSA key or initialize a new one (or global). */
    rng = WOLFSSL_RSA_GetRNG(rsa, (WC_RNG**)&tmpRng, &initTmpRng);
    if (rng == NULL) {
        /* Something went wrong so return memory error. */
        ret = MEMORY_E;
    }
    if (ret == 0) {
        /* Generate an RSA key. */
        ret = wc_MakeRsaKey((RsaKey*)rsa->internal, bits,
            (long)wolfSSL_BN_get_word(e), rng);
        if (ret != MP_OKAY) {
            WOLFSSL_ERROR_MSG("wc_MakeRsaKey failed");
        }
    }
    if (ret == 0) {
        /* Get the values from wolfCrypt RSA key into external RSA key. */
        ret = SetRsaExternal(rsa);
        if (ret == 1) {
            /* Internal matches external. */
            rsa->inSet = 1;
            /* Return success. */
            ret = 0;
        }
        else {
            /* Something went wrong so return memory error. */
            ret = MEMORY_E;
        }
    }

    /* Finalize RNG if initialized in WOLFSSL_RSA_GetRNG(). */
    if (initTmpRng) {
        wc_FreeRng(tmpRng);
    }
#ifdef WOLFSSL_SMALL_STACK
    /* Dispose of any allocated RNG. */
    XFREE(tmpRng, NULL, DYNAMIC_TYPE_RNG);
#endif

    return ret;
#else
    WOLFSSL_ERROR_MSG("No Key Gen built in");

    (void)rsa;
    (void)e;
    (void)bits;

    return NOT_COMPILED_IN;
#endif
}

/* Generate an RSA key that has the specified modulus size and public exponent.
 *
 * Note: Because of wc_MakeRsaKey an RSA key size generated can be rounded
 *       down to nearest multiple of 8. For example generating a key of size
 *       2999 bits will make a key of size 374 bytes instead of 375 bytes.
 *
 * @param [in]      bits  Number of bits that the modulus must have i.e. 2048.
 * @param [in]      e     Public exponent to use i.e. 65537.
 * @param [in]      cb    Status callback. Unused.
 * @param [in]      data  Data to pass to status callback. Unused.
 * @return  A new RSA key on success.
 * @return  NULL on failure.
 */
WOLFSSL_RSA* wolfSSL_RSA_generate_key(int bits, unsigned long e,
    void(*cb)(int, int, void*), void* data)
{
    WOLFSSL_RSA*    rsa = NULL;
    WOLFSSL_BIGNUM* bn  = NULL;
    int             err = 0;

    WOLFSSL_ENTER("wolfSSL_RSA_generate_key");

    (void)cb;
    (void)data;

    /* Validate bits. */
    if (bits < 0) {
        WOLFSSL_ERROR_MSG("Bad argument: bits was less than 0");
        err = 1;
    }
    /* Create a new BN to hold public exponent - for when wolfCrypt supports
     * longer values. */
    if ((!err) && ((bn = wolfSSL_BN_new()) == NULL)) {
        WOLFSSL_ERROR_MSG("Error creating big number");
        err = 1;
    }
    /* Set public exponent. */
    if ((!err) && (wolfSSL_BN_set_word(bn, e) != 1)) {
        WOLFSSL_ERROR_MSG("Error using e value");
        err = 1;
    }

    /* Create an RSA key object to hold generated key. */
    if ((!err) && ((rsa = wolfSSL_RSA_new()) == NULL)) {
        WOLFSSL_ERROR_MSG("memory error");
        err = 1;
    }
    while (!err) {
        int ret;

        /* Use wolfCrypt to generate RSA key. */
        ret = wolfssl_rsa_generate_key_native(rsa, bits, bn, NULL);
    #ifdef HAVE_FIPS
        /* Keep trying if failed to find a prime. */
        if (ret == WC_NO_ERR_TRACE(PRIME_GEN_E)) {
            continue;
        }
    #endif
        if (ret != WOLFSSL_ERROR_NONE) {
            /* Unrecoverable error in generation. */
            err = 1;
        }
        /* Done generating - unrecoverable error or success. */
        break;
    }
    if (err) {
        /* Dispose of RSA key object if generation didn't work. */
        wolfSSL_RSA_free(rsa);
        /* Returning NULL on error. */
        rsa = NULL;
    }
    /* Dispose of the temporary BN used for the public exponent. */
    wolfSSL_BN_free(bn);

    return rsa;
}

/* Generate an RSA key that has the specified modulus size and public exponent.
 *
 * Note: Because of wc_MakeRsaKey an RSA key size generated can be rounded
 *       down to nearest multiple of 8. For example generating a key of size
 *       2999 bits will make a key of size 374 bytes instead of 375 bytes.
 *
 * @param [in]      bits  Number of bits that the modulus must have i.e. 2048.
 * @param [in]      e     Public exponent to use, i.e. 65537, as a BN.
 * @param [in]      cb    Status callback. Unused.
 * @return 1 on success.
 * @return 0 on failure.
 */
int wolfSSL_RSA_generate_key_ex(WOLFSSL_RSA* rsa, int bits, WOLFSSL_BIGNUM* e,
    void* cb)
{
    int ret = 1;

    /* Validate parameters. */
    if ((rsa == NULL) || (rsa->internal == NULL)) {
        WOLFSSL_ERROR_MSG("bad arguments");
        ret = 0;
    }
    else {
        for (;;) {
            /* Use wolfCrypt to generate RSA key. */
            int gen_ret = wolfssl_rsa_generate_key_native(rsa, bits, e, cb);
        #ifdef HAVE_FIPS
            /* Keep trying again if public key value didn't work. */
            if (gen_ret == WC_NO_ERR_TRACE(PRIME_GEN_E)) {
                continue;
            }
        #endif
            if (gen_ret != WOLFSSL_ERROR_NONE) {
                /* Unrecoverable error in generation. */
                ret = 0;
            }
            /* Done generating - unrecoverable error or success. */
            break;
        }
    }

    return ret;
}

#endif /* OPENSSL_EXTRA */

/*
 * RSA padding APIs
 */

#if defined(WC_RSA_PSS) && (defined(OPENSSL_ALL) || defined(WOLFSSL_ASIO) || \
        defined(WOLFSSL_HAPROXY) || defined(WOLFSSL_NGINX))
#if !defined(HAVE_FIPS) || FIPS_VERSION_GT(2,0)
/* Add PKCS#1 PSS padding to hash.
 *
 *
 *                                +-----------+
 *                                |     M     |
 *                                +-----------+
 *                                      |
 *                                      V
 *                                    Hash
 *                                      |
 *                                      V
 *                        +--------+----------+----------+
 *                   M' = |Padding1|  mHash   |   salt   |
 *                        +--------+----------+----------+
 *                                       |
 *             +--------+----------+     V
 *       DB =  |Padding2|maskedseed|   Hash
 *             +--------+----------+     |
 *                       |               |
 *                       V               |    +--+
 *                      xor <--- MGF <---|    |bc|
 *                       |               |    +--+
 *                       |               |      |
 *                       V               V      V
 *             +-------------------+----------+--+
 *       EM =  |    maskedDB       |maskedseed|bc|
 *             +-------------------+----------+--+
 * Diagram taken from https://tools.ietf.org/html/rfc3447#section-9.1
 *
 * @param [in]  rsa      RSA key.
 * @param [out] em       Encoded message.
 * @param [in[  mHash    Message hash.
 * @param [in]  hashAlg  Hash algorithm.
 * @param [in]  saltLen  Length of salt to generate.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_RSA_padding_add_PKCS1_PSS(WOLFSSL_RSA *rsa, unsigned char *em,
    const unsigned char *mHash, const WOLFSSL_EVP_MD *hashAlg, int saltLen)
{
    int ret = 1;
    enum wc_HashType hashType;
    int hashLen = 0;
    int emLen = 0;
    int mgf = 0;
    int initTmpRng = 0;
    WC_RNG *rng = NULL;
#ifdef WOLFSSL_SMALL_STACK
    WC_RNG* tmpRng = NULL;
#else
    WC_RNG  _tmpRng[1];
    WC_RNG* tmpRng = _tmpRng;
#endif

    WOLFSSL_ENTER("wolfSSL_RSA_padding_add_PKCS1_PSS");

    /* Validate parameters. */
    if ((rsa == NULL) || (em == NULL) || (mHash == NULL) || (hashAlg == NULL)) {
        ret = 0;
    }

    if (ret == 1) {
        /* Get/create an RNG. */
        rng = WOLFSSL_RSA_GetRNG(rsa, (WC_RNG**)&tmpRng, &initTmpRng);
        if (rng == NULL) {
            WOLFSSL_ERROR_MSG("WOLFSSL_RSA_GetRNG error");
            ret = 0;
        }
    }

    /* TODO: use wolfCrypt RSA key to get emLen and bits? */
    /* Set the external data from the wolfCrypt RSA key if not done. */
    if ((ret == 1) && (!rsa->exSet)) {
        ret = SetRsaExternal(rsa);
    }

    if (ret == 1) {
        /* Get the wolfCrypt hash algorithm type. */
        hashType = EvpMd2MacType(hashAlg);
        if (hashType > WC_HASH_TYPE_MAX) {
            WOLFSSL_ERROR_MSG("EvpMd2MacType error");
            ret = 0;
        }
    }
    if (ret == 1) {
        /* Get the wolfCrypt MGF algorithm from hash algorithm. */
        mgf = wc_hash2mgf(hashType);
        if (mgf == WC_MGF1NONE) {
            WOLFSSL_ERROR_MSG("wc_hash2mgf error");
            ret = 0;
        }
    }
    if (ret == 1) {
        /* Get the length of the hash output. */
        hashLen = wolfSSL_EVP_MD_size(hashAlg);
        if (hashLen < 0) {
            WOLFSSL_ERROR_MSG("wolfSSL_EVP_MD_size error");
            ret = 0;
        }
    }

    if (ret == 1) {
        /* Get length of RSA key - encrypted message length. */
        emLen = wolfSSL_RSA_size(rsa);
        if (emLen <= 0) {
            WOLFSSL_ERROR_MSG("wolfSSL_RSA_size error");
            ret = 0;
        }
    }

    if (ret == 1) {
        /* Calculate the salt length to use for special cases. */
        /* TODO: use special case wolfCrypt values? */
        switch (saltLen) {
        /* Negative saltLen values are treated differently. */
        case RSA_PSS_SALTLEN_DIGEST:
            saltLen = hashLen;
            break;
        case RSA_PSS_SALTLEN_MAX_SIGN:
        case RSA_PSS_SALTLEN_MAX:
        #ifdef WOLFSSL_PSS_LONG_SALT
            saltLen = emLen - hashLen - 2;
        #else
            saltLen = hashLen;
        #endif
            break;
        default:
            if (saltLen < 0) {
                /* No other negative values implemented. */
                WOLFSSL_ERROR_MSG("invalid saltLen");
                ret = 0;
            }
        }
    }

    if (ret == 1) {
        /* Generate RSA PKCS#1 PSS padding for hash using wolfCrypt. */
        if (wc_RsaPad_ex(mHash, (word32)hashLen, em, (word32)emLen,
                RSA_BLOCK_TYPE_1, rng, WC_RSA_PSS_PAD, hashType, mgf, NULL, 0,
                saltLen, wolfSSL_BN_num_bits(rsa->n), NULL) != MP_OKAY) {
            WOLFSSL_ERROR_MSG("wc_RsaPad_ex error");
            ret = 0;
        }
    }

    /* Finalize RNG if initialized in WOLFSSL_RSA_GetRNG(). */
    if (initTmpRng) {
        wc_FreeRng(tmpRng);
    }
#ifdef WOLFSSL_SMALL_STACK
    /* Dispose of any allocated RNG. */
    XFREE(tmpRng, NULL, DYNAMIC_TYPE_RNG);
#endif

    return ret;
}

/* Checks that the hash is valid for the RSA PKCS#1 PSS encoded message.
 *
 * Refer to wolfSSL_RSA_padding_add_PKCS1_PSS for a diagram.
 *
 * @param [in]  rsa      RSA key.
 * @param [in[  mHash    Message hash.
 * @param [in]  hashAlg  Hash algorithm.
 * @param [in]  em       Encoded message.
 * @param [in]  saltLen  Length of salt to generate.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_RSA_verify_PKCS1_PSS(WOLFSSL_RSA *rsa, const unsigned char *mHash,
                                 const WOLFSSL_EVP_MD *hashAlg,
                                 const unsigned char *em, int saltLen)
{
    int ret = 1;
    int hashLen = 0;
    int mgf = 0;
    int emLen = 0;
    int mPrimeLen = 0;
    enum wc_HashType hashType = WC_HASH_TYPE_NONE;
    byte *mPrime = NULL;
    byte *buf = NULL;

    WOLFSSL_ENTER("wolfSSL_RSA_verify_PKCS1_PSS");

    /* Validate parameters. */
    if ((rsa == NULL) || (mHash == NULL) || (hashAlg == NULL) || (em == NULL)) {
        ret = 0;
    }

    /* TODO: use wolfCrypt RSA key to get emLen and bits? */
    /* Set the external data from the wolfCrypt RSA key if not done. */
    if ((ret == 1) && (!rsa->exSet)) {
        ret = SetRsaExternal(rsa);
    }

    if (ret == 1) {
        /* Get hash length for hash algorithm. */
        hashLen = wolfSSL_EVP_MD_size(hashAlg);
        if (hashLen < 0) {
            ret = 0;
        }
    }

    if (ret == 1) {
        /* Get length of RSA key - encrypted message length. */
        emLen = wolfSSL_RSA_size(rsa);
        if (emLen <= 0) {
            WOLFSSL_ERROR_MSG("wolfSSL_RSA_size error");
            ret = 0;
        }
    }

    if (ret == 1) {
        /* Calculate the salt length to use for special cases. */
        switch (saltLen) {
        /* Negative saltLen values are treated differently */
        case RSA_PSS_SALTLEN_DIGEST:
            saltLen = hashLen;
            break;
        case RSA_PSS_SALTLEN_AUTO:
        #ifdef WOLFSSL_PSS_SALT_LEN_DISCOVER
            saltLen = RSA_PSS_SALT_LEN_DISCOVER;
            break;
        #endif
        case RSA_PSS_SALTLEN_MAX:
        #ifdef WOLFSSL_PSS_LONG_SALT
            saltLen = emLen - hashLen - 2;
        #else
            saltLen = hashLen;
        #endif
            break;
        default:
            if (saltLen < 0) {
                /* No other negative values implemented. */
                WOLFSSL_ERROR_MSG("invalid saltLen");
                ret = 0;
            }
        }
    }

    if (ret == 1) {
        /* Get the wolfCrypt hash algorithm type. */
        hashType = EvpMd2MacType(hashAlg);
        if (hashType > WC_HASH_TYPE_MAX) {
            WOLFSSL_ERROR_MSG("EvpMd2MacType error");
            ret = 0;
        }
    }

    if (ret == 1) {
        /* Get the wolfCrypt MGF algorithm from hash algorithm. */
        if ((mgf = wc_hash2mgf(hashType)) == WC_MGF1NONE) {
            WOLFSSL_ERROR_MSG("wc_hash2mgf error");
            ret = 0;
        }
    }

    if (ret == 1) {
        /* Allocate buffer to unpad inline with. */
        buf = (byte*)XMALLOC((size_t)emLen, NULL, DYNAMIC_TYPE_TMP_BUFFER);
        if (buf == NULL) {
            WOLFSSL_ERROR_MSG("malloc error");
            ret = 0;
        }
    }

    if (ret == 1) {
        /* Copy encrypted message to temp for inline unpadding. */
        XMEMCPY(buf, em, (size_t)emLen);

        /* Remove and verify the PSS padding. */
        mPrimeLen = wc_RsaUnPad_ex(buf, (word32)emLen, &mPrime,
            RSA_BLOCK_TYPE_1, WC_RSA_PSS_PAD, hashType, mgf, NULL, 0, saltLen,
            wolfSSL_BN_num_bits(rsa->n), NULL);
        if (mPrimeLen < 0) {
            WOLFSSL_ERROR_MSG("wc_RsaPad_ex error");
            ret = 0;
        }
    }

    if (ret == 1) {
        /* Verify the hash is correct. */
        if (wc_RsaPSS_CheckPadding_ex(mHash, (word32)hashLen, mPrime,
                (word32)mPrimeLen, hashType, saltLen,
                wolfSSL_BN_num_bits(rsa->n)) != MP_OKAY) {
            WOLFSSL_ERROR_MSG("wc_RsaPSS_CheckPadding_ex error");
            ret = 0;
        }
    }

    /* Dispose of any allocated buffer. */
    XFREE(buf, NULL, DYNAMIC_TYPE_TMP_BUFFER);
    return ret;
}
#endif /* !HAVE_FIPS || FIPS_VERSION_GT(2,0) */
#endif /* WC_RSA_PSS && (OPENSSL_ALL || WOLFSSL_ASIO || WOLFSSL_HAPROXY ||
        *                WOLFSSL_NGINX) */

/*
 * RSA sign/verify APIs
 */

#ifndef WOLFSSL_PSS_SALT_LEN_DISCOVER
    #define DEF_PSS_SALT_LEN    RSA_PSS_SALT_LEN_DEFAULT
#else
    #define DEF_PSS_SALT_LEN    RSA_PSS_SALT_LEN_DISCOVER
#endif

#if defined(OPENSSL_EXTRA)

/* Encode the message hash.
 *
 * Used by signing and verification.
 *
 * @param [in]  hashAlg   Hash algorithm OID.
 * @param [in]  hash      Hash of message to encode for signing.
 * @param [in]  hLen      Length of hash of message.
 * @param [out] enc       Encoded message hash.
 * @param [out] encLen    Length of encoded message hash.
 * @param [in]  padding   Which padding scheme is being used.
 * @return  1 on success.
 * @return  0 on failure.
 */
static int wolfssl_rsa_sig_encode(int hashAlg, const unsigned char* hash,
    unsigned int hLen, unsigned char* enc, unsigned int* encLen, int padding)
{
    int ret = 1;
    int hType = WC_HASH_TYPE_NONE;

    /* Validate parameters. */
    if ((hash == NULL) || (enc == NULL) || (encLen == NULL)) {
        ret = 0;
    }

    if ((ret == 1) && (hashAlg != NID_undef) &&
            (padding == RSA_PKCS1_PADDING)) {
        /* Convert hash algorithm to hash type for PKCS#1.5 padding. */
        hType = (int)nid2oid(hashAlg, oidHashType);
        if (hType == -1) {
            ret = 0;
        }
    }
    if ((ret == 1) && (padding == RSA_PKCS1_PADDING)) {
        /* PKCS#1.5 encoding. */
        word32 encSz = wc_EncodeSignature(enc, hash, hLen, hType);
        if (encSz == 0) {
            WOLFSSL_ERROR_MSG("Bad Encode Signature");
            ret = 0;
        }
        else  {
            *encLen = (unsigned int)encSz;
        }
    }
    /* Other padding schemes require the hash as is. */
    if ((ret == 1) && (padding != RSA_PKCS1_PADDING)) {
        XMEMCPY(enc, hash, hLen);
        *encLen = hLen;
    }

    return ret;
}

/* Sign the message hash using hash algorithm and RSA key.
 *
 * @param [in]  hashAlg   Hash algorithm OID.
 * @param [in]  hash      Hash of message to encode for signing.
 * @param [in]  hLen      Length of hash of message.
 * @param [out] enc       Encoded message hash.
 * @param [out] encLen    Length of encoded message hash.
 * @param [in]  rsa       RSA key.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_RSA_sign(int hashAlg, const unsigned char* hash, unsigned int hLen,
    unsigned char* sigRet, unsigned int* sigLen, WOLFSSL_RSA* rsa)
{
    if (sigLen != NULL) {
        /* No size checking in this API */
        *sigLen = RSA_MAX_SIZE / CHAR_BIT;
    }
    /* flag is 1: output complete signature. */
    return wolfSSL_RSA_sign_generic_padding(hashAlg, hash, hLen, sigRet,
        sigLen, rsa, 1, RSA_PKCS1_PADDING);
}

/* Sign the message hash using hash algorithm and RSA key.
 *
 * Not OpenSSL API.
 *
 * @param [in]  hashAlg   Hash algorithm NID.
 * @param [in]  hash      Hash of message to encode for signing.
 * @param [in]  hLen      Length of hash of message.
 * @param [out] enc       Encoded message hash.
 * @param [out] encLen    Length of encoded message hash.
 * @param [in]  rsa       RSA key.
 * @param [in]  flag      When 1: Output encrypted signature.
 *                        When 0: Output encoded hash.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_RSA_sign_ex(int hashAlg, const unsigned char* hash,
    unsigned int hLen, unsigned char* sigRet, unsigned int* sigLen,
    WOLFSSL_RSA* rsa, int flag)
{
    int ret = 0;

    if ((flag == 0) || (flag == 1)) {
        if (sigLen != NULL) {
            /* No size checking in this API */
            *sigLen = RSA_MAX_SIZE / CHAR_BIT;
        }
        ret = wolfSSL_RSA_sign_generic_padding(hashAlg, hash, hLen, sigRet,
            sigLen, rsa, flag, RSA_PKCS1_PADDING);
    }

    return ret;
}

/**
 * Sign a message hash with the chosen message digest, padding, and RSA key.
 *
 * Not OpenSSL API.
 *
 * @param [in]      hashAlg  Hash NID
 * @param [in]      hash     Message hash to sign.
 * @param [in]      mLen     Length of message hash to sign.
 * @param [out]     sigRet   Output buffer.
 * @param [in, out] sigLen   On Input: length of sigRet buffer.
 *                           On Output: length of data written to sigRet.
 * @param [in]      rsa      RSA key used to sign the input.
 * @param [in]      flag     1: Output the signature.
 *                           0: Output the value that the unpadded signature
 *                              should be compared to.
 * @param [in]      padding  Padding to use. Only RSA_PKCS1_PSS_PADDING and
 *                           RSA_PKCS1_PADDING are currently supported for
 *                           signing.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_RSA_sign_generic_padding(int hashAlg, const unsigned char* hash,
    unsigned int hLen, unsigned char* sigRet, unsigned int* sigLen,
    WOLFSSL_RSA* rsa, int flag, int padding)
{
    int     ret        = 1;
    word32  outLen     = 0;
    int     signSz     = 0;
    WC_RNG* rng        = NULL;
    int     initTmpRng = 0;
#ifdef WOLFSSL_SMALL_STACK
    WC_RNG* tmpRng     = NULL;
    byte*   encodedSig = NULL;
#else
    WC_RNG  _tmpRng[1];
    WC_RNG* tmpRng = _tmpRng;
    byte    encodedSig[MAX_ENCODED_SIG_SZ];
#endif
    unsigned int encSz = 0;


    WOLFSSL_ENTER("wolfSSL_RSA_sign_generic_padding");

    if (flag == 0) {
        /* Only encode message. */
        return wolfssl_rsa_sig_encode(hashAlg, hash, hLen, sigRet, sigLen,
            padding);
    }

    /* Validate parameters. */
    if ((hash == NULL) || (sigRet == NULL) || sigLen == NULL || rsa == NULL) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = 0;
    }

    /* Set wolfCrypt RSA key data from external if not already done. */
    if ((ret == 1) && (!rsa->inSet) && (SetRsaInternal(rsa) != 1)) {
        ret = 0;
    }

    if (ret == 1) {
        /* Get the maximum signature length. */
        outLen = (word32)wolfSSL_BN_num_bytes(rsa->n);
        /* Check not an error return. */
        if (outLen == 0) {
            WOLFSSL_ERROR_MSG("Bad RSA size");
            ret = 0;
        }
        /* Check signature buffer is big enough. */
        else if (outLen > *sigLen) {
            WOLFSSL_ERROR_MSG("Output buffer too small");
            ret = 0;
        }
    }

#ifdef WOLFSSL_SMALL_STACK
    if (ret == 1) {
        /* Allocate encoded signature buffer if doing PKCS#1 padding. */
        encodedSig = (byte*)XMALLOC(MAX_ENCODED_SIG_SZ, NULL,
            DYNAMIC_TYPE_SIGNATURE);
        if (encodedSig == NULL) {
            ret = 0;
        }
    }
#endif

    if (ret == 1) {
        /* Get/create an RNG. */
        rng = WOLFSSL_RSA_GetRNG(rsa, (WC_RNG**)&tmpRng, &initTmpRng);
        if (rng == NULL) {
            WOLFSSL_ERROR_MSG("WOLFSSL_RSA_GetRNG error");
            ret = 0;
        }
    }

    /* Either encodes with PKCS#1.5 or copies hash into encodedSig. */
    if ((ret == 1) && (wolfssl_rsa_sig_encode(hashAlg, hash, hLen, encodedSig,
            &encSz, padding) == 0)) {
        WOLFSSL_ERROR_MSG("Bad Encode Signature");
        ret = 0;
    }

    if (ret == 1) {
        switch (padding) {
    #if defined(WC_RSA_NO_PADDING) || defined(WC_RSA_DIRECT)
        case RSA_NO_PADDING:
            if ((signSz = wc_RsaDirect(encodedSig, encSz, sigRet, &outLen,
                (RsaKey*)rsa->internal, RSA_PRIVATE_ENCRYPT, rng)) <= 0) {
                WOLFSSL_ERROR_MSG("Bad Rsa Sign no pad");
                ret = 0;
            }
            break;
    #endif
    #if defined(WC_RSA_PSS) && !defined(HAVE_SELFTEST) && \
        (!defined(HAVE_FIPS) || FIPS_VERSION_GE(5,1))
        case RSA_PKCS1_PSS_PADDING:
        {
            enum wc_HashType hType =
                wc_OidGetHash((int)nid2oid(hashAlg, oidHashType));
        #ifndef WOLFSSL_PSS_SALT_LEN_DISCOVER
            WOLFSSL_MSG("Using RSA-PSS with hash length salt. "
                        "OpenSSL uses max length by default.");
        #endif
            /* Create RSA PSS signature. */
            if ((signSz = wc_RsaPSS_Sign_ex(encodedSig, encSz, sigRet, outLen,
                    hType, wc_hash2mgf(hType), DEF_PSS_SALT_LEN,
                    (RsaKey*)rsa->internal, rng)) <= 0) {
                WOLFSSL_ERROR_MSG("Bad Rsa Sign");
                ret = 0;
            }
            break;
        }
    #endif
    #ifndef WC_NO_RSA_OAEP
        case RSA_PKCS1_OAEP_PADDING:
            /* Not a signature padding scheme. */
            WOLFSSL_ERROR_MSG("RSA_PKCS1_OAEP_PADDING not supported for "
                              "signing");
            ret = 0;
            break;
    #endif
        case RSA_PKCS1_PADDING:
        {
            /* Sign (private encrypt) PKCS#1 encoded signature. */
            if ((signSz = wc_RsaSSL_Sign(encodedSig, encSz, sigRet, outLen,
                    (RsaKey*)rsa->internal, rng)) <= 0) {
                WOLFSSL_ERROR_MSG("Bad Rsa Sign");
                ret = 0;
            }
            break;
        }
        default:
            WOLFSSL_ERROR_MSG("Unsupported padding");
            ret = 0;
            break;
        }
    }

    if (ret == 1) {
        /* Return the size of signature generated. */
        *sigLen = (unsigned int)signSz;
    }

    /* Finalize RNG if initialized in WOLFSSL_RSA_GetRNG(). */
    if (initTmpRng) {
        wc_FreeRng(tmpRng);
    }
#ifdef WOLFSSL_SMALL_STACK
    /* Dispose of any allocated RNG and encoded signature. */
    XFREE(tmpRng,     NULL, DYNAMIC_TYPE_RNG);
    XFREE(encodedSig, NULL, DYNAMIC_TYPE_SIGNATURE);
#endif

    WOLFSSL_LEAVE("wolfSSL_RSA_sign_generic_padding", ret);
    return ret;
}

/**
 * Verify a message hash with the chosen message digest, padding, and RSA key.
 *
 * @param [in]  hashAlg  Hash NID
 * @param [in]  hash     Message hash.
 * @param [in]  mLen     Length of message hash.
 * @param [in]  sigRet   Signature data.
 * @param [in]  sigLen   Length of signature data.
 * @param [in]  rsa      RSA key used to sign the input
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_RSA_verify(int hashAlg, const unsigned char* hash,
    unsigned int hLen, const unsigned char* sig, unsigned int sigLen,
    WOLFSSL_RSA* rsa)
{
    return wolfSSL_RSA_verify_ex(hashAlg, hash, hLen, sig, sigLen, rsa,
        RSA_PKCS1_PADDING);
}

/**
 * Verify a message hash with the chosen message digest, padding, and RSA key.
 *
 * Not OpenSSL API.
 *
 * @param [in]  hashAlg  Hash NID
 * @param [in]  hash     Message hash.
 * @param [in]  mLen     Length of message hash.
 * @param [in]  sigRet   Signature data.
 * @param [in]  sigLen   Length of signature data.
 * @param [in]  rsa      RSA key used to sign the input
 * @param [in]  padding  Padding to use. Only RSA_PKCS1_PSS_PADDING and
 *                       RSA_PKCS1_PADDING are currently supported for
 *                       signing.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_RSA_verify_ex(int hashAlg, const unsigned char* hash,
    unsigned int hLen, const unsigned char* sig, unsigned int sigLen,
    WOLFSSL_RSA* rsa, int padding)
{
    int              ret    = 1;
#ifdef WOLFSSL_SMALL_STACK
    unsigned char*   encodedSig = NULL;
#else
    unsigned char    encodedSig[MAX_ENCODED_SIG_SZ];
#endif
    unsigned char*   sigDec = NULL;
    unsigned int     len    = MAX_ENCODED_SIG_SZ;
    int              verLen = 0;
#if (!defined(HAVE_FIPS) || FIPS_VERSION_GE(5, 1)) && !defined(HAVE_SELFTEST)
    enum wc_HashType hType = WC_HASH_TYPE_NONE;
#endif

    WOLFSSL_ENTER("wolfSSL_RSA_verify");

    /* Validate parameters. */
    if ((hash == NULL) || (sig == NULL) || (rsa == NULL)) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = 0;
    }

    if (ret == 1) {
        /* Allocate memory for decrypted signature. */
        sigDec = (unsigned char *)XMALLOC(sigLen, NULL,
            DYNAMIC_TYPE_TMP_BUFFER);
        if (sigDec == NULL) {
            WOLFSSL_ERROR_MSG("Memory allocation failure");
            ret = 0;
        }
    }
#ifdef WOLFSSL_SMALL_STACK
    if ((ret == 1) && (padding != RSA_PKCS1_PSS_PADDING)) {
        /* Allocate memory for encoded signature. */
        encodedSig = (unsigned char *)XMALLOC(len, NULL,
            DYNAMIC_TYPE_TMP_BUFFER);
        if (encodedSig == NULL) {
            WOLFSSL_ERROR_MSG("Memory allocation failure");
            ret = 0;
        }
    }
#endif
    if ((ret == 1) && (padding != RSA_PKCS1_PSS_PADDING)) {
        /* Make encoded signature to compare with decrypted signature. */
        if (wolfssl_rsa_sig_encode(hashAlg, hash, hLen, encodedSig, &len,
                padding) <= 0) {
            WOLFSSL_ERROR_MSG("Message Digest Error");
            ret = 0;
        }
    }
    if (ret == 1) {
        /* Decrypt signature */
    #if (!defined(HAVE_FIPS) || FIPS_VERSION_GE(5, 1)) && \
        !defined(HAVE_SELFTEST)
        hType = wc_OidGetHash((int)nid2oid(hashAlg, oidHashType));
        if ((verLen = wc_RsaSSL_Verify_ex2(sig, sigLen, (unsigned char *)sigDec,
                sigLen, (RsaKey*)rsa->internal, padding, hType)) <= 0) {
            WOLFSSL_ERROR_MSG("RSA Decrypt error");
            ret = 0;
        }
    #else
        verLen = wc_RsaSSL_Verify(sig, sigLen, (unsigned char *)sigDec, sigLen,
            (RsaKey*)rsa->internal);
        if (verLen < 0) {
            ret = 0;
        }
    #endif
    }
    if (ret == 1) {
    #if defined(WC_RSA_PSS) && !defined(HAVE_SELFTEST) && \
        (!defined(HAVE_FIPS) || FIPS_VERSION_GE(5, 1))
        if (padding == RSA_PKCS1_PSS_PADDING) {
            /* Check PSS padding is valid. */
            if (wc_RsaPSS_CheckPadding_ex(hash, hLen, sigDec, (word32)verLen,
                    hType, DEF_PSS_SALT_LEN,
                    mp_count_bits(&((RsaKey*)rsa->internal)->n)) != 0) {
                WOLFSSL_ERROR_MSG("wc_RsaPSS_CheckPadding_ex error");
                ret = 0;
            }
        }
        else
    #endif /* WC_RSA_PSS && !HAVE_SELFTEST && (!HAVE_FIPS ||
            * FIPS_VERSION >= 5.1) */
        /* Compare decrypted signature to encoded signature. */
        if (((int)len != verLen) ||
                (XMEMCMP(encodedSig, sigDec, (size_t)verLen) != 0)) {
            WOLFSSL_ERROR_MSG("wolfSSL_RSA_verify_ex failed");
            ret = 0;
        }
    }

    /* Dispose of any allocated data. */
#ifdef WOLFSSL_SMALL_STACK
    XFREE(encodedSig, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
    XFREE(sigDec, NULL, DYNAMIC_TYPE_TMP_BUFFER);
    return ret;
}

/*
 * RSA public/private encrypt/decrypt APIs
 */

/* Encrypt with the RSA public key.
 *
 * Return compliant with OpenSSL.
 *
 * @param [in]  len      Length of data to encrypt.
 * @param [in]  from     Data to encrypt.
 * @param [out] to       Encrypted data.
 * @param [in]  rsa      RSA key.
 * @param [in]  padding  Type of padding to place around plaintext.
 * @return  Size of encrypted data on success.
 * @return  -1 on failure.
 */
int wolfSSL_RSA_public_encrypt(int len, const unsigned char* from,
    unsigned char* to, WOLFSSL_RSA* rsa, int padding)
{
    int ret = 0;
    int initTmpRng = 0;
    WC_RNG *rng = NULL;
#ifdef WOLFSSL_SMALL_STACK
    WC_RNG* tmpRng = NULL;
#else
    WC_RNG  _tmpRng[1];
    WC_RNG* tmpRng = _tmpRng;
#endif
#if !defined(HAVE_FIPS)
    int  mgf = WC_MGF1NONE;
    enum wc_HashType hash = WC_HASH_TYPE_NONE;
    int pad_type = WC_RSA_NO_PAD;
#endif
    int outLen = 0;

    WOLFSSL_ENTER("wolfSSL_RSA_public_encrypt");

    /* Validate parameters. */
    if ((len < 0) || (rsa == NULL) || (rsa->internal == NULL) ||
            (from == NULL)) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = -1;
    }

    if (ret == 0) {
    #if !defined(HAVE_FIPS)
        /* Convert to wolfCrypt padding, hash and MGF. */
        switch (padding) {
        case RSA_PKCS1_PADDING:
            pad_type = WC_RSA_PKCSV15_PAD;
            break;
        case RSA_PKCS1_OAEP_PADDING:
            pad_type = WC_RSA_OAEP_PAD;
            hash = WC_HASH_TYPE_SHA;
            mgf = WC_MGF1SHA1;
            break;
        case RSA_NO_PADDING:
            pad_type = WC_RSA_NO_PAD;
            break;
        default:
            WOLFSSL_ERROR_MSG("RSA_public_encrypt doesn't support padding "
                              "scheme");
            ret = -1;
        }
    #else
        /* Check for supported padding schemes in FIPS. */
        /* TODO: Do we support more schemes in later versions of FIPS? */
        if (padding != RSA_PKCS1_PADDING) {
            WOLFSSL_ERROR_MSG("RSA_public_encrypt pad type not supported in "
                              "FIPS");
            ret = -1;
        }
    #endif
    }

    /* Set wolfCrypt RSA key data from external if not already done. */
    if ((ret == 0) && (!rsa->inSet) && (SetRsaInternal(rsa) != 1)) {
        ret = -1;
    }

    if (ret == 0) {
        /* Calculate maximum length of encrypted data. */
        outLen = wolfSSL_RSA_size(rsa);
        if (outLen == 0) {
            WOLFSSL_ERROR_MSG("Bad RSA size");
            ret = -1;
        }
    }

    if (ret == 0) {
        /* Get an RNG. */
        rng = WOLFSSL_RSA_GetRNG(rsa, (WC_RNG**)&tmpRng, &initTmpRng);
        if (rng == NULL) {
            ret = -1;
        }
    }

    if (ret == 0) {
        /* Use wolfCrypt to public-encrypt with RSA key. */
    #if !defined(HAVE_FIPS)
        ret = wc_RsaPublicEncrypt_ex(from, (word32)len, to, (word32)outLen,
            (RsaKey*)rsa->internal, rng, pad_type, hash, mgf, NULL, 0);
    #else
        ret = wc_RsaPublicEncrypt(from, (word32)len, to, (word32)outLen,
            (RsaKey*)rsa->internal, rng);
    #endif
    }

    /* Finalize RNG if initialized in WOLFSSL_RSA_GetRNG(). */
    if (initTmpRng) {
        wc_FreeRng(tmpRng);
    }
#ifdef WOLFSSL_SMALL_STACK
    /* Dispose of any allocated RNG. */
    XFREE(tmpRng, NULL, DYNAMIC_TYPE_RNG);
#endif

    /* wolfCrypt error means return -1. */
    if (ret <= 0) {
        ret = -1;
    }
    WOLFSSL_LEAVE("wolfSSL_RSA_public_encrypt", ret);
    return ret;
}

/* Decrypt with the RSA public key.
 *
 * Return compliant with OpenSSL.
 *
 * @param [in]  len      Length of encrypted data.
 * @param [in]  from     Encrypted data.
 * @param [out] to       Decrypted data.
 * @param [in]  rsa      RSA key.
 * @param [in]  padding  Type of padding to around plaintext to remove.
 * @return  Size of decrypted data on success.
 * @return  -1 on failure.
 */
int wolfSSL_RSA_private_decrypt(int len, const unsigned char* from,
    unsigned char* to, WOLFSSL_RSA* rsa, int padding)
{
    int ret = 0;
#if !defined(HAVE_FIPS)
    int mgf = WC_MGF1NONE;
    enum wc_HashType hash = WC_HASH_TYPE_NONE;
    int pad_type = WC_RSA_NO_PAD;
#endif
    int outLen = 0;

    WOLFSSL_ENTER("wolfSSL_RSA_private_decrypt");

    /* Validate parameters. */
    if ((len < 0) || (rsa == NULL) || (rsa->internal == NULL) ||
            (from == NULL)) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = -1;
    }

    if (ret == 0) {
    #if !defined(HAVE_FIPS)
        switch (padding) {
        case RSA_PKCS1_PADDING:
            pad_type = WC_RSA_PKCSV15_PAD;
            break;
        case RSA_PKCS1_OAEP_PADDING:
            pad_type = WC_RSA_OAEP_PAD;
            hash = WC_HASH_TYPE_SHA;
            mgf = WC_MGF1SHA1;
            break;
        case RSA_NO_PADDING:
            pad_type = WC_RSA_NO_PAD;
            break;
        default:
            WOLFSSL_ERROR_MSG("RSA_private_decrypt unsupported padding");
            ret = -1;
        }
    #else
        /* Check for supported padding schemes in FIPS. */
        /* TODO: Do we support more schemes in later versions of FIPS? */
        if (padding != RSA_PKCS1_PADDING) {
            WOLFSSL_ERROR_MSG("RSA_public_encrypt pad type not supported in "
                              "FIPS");
            ret = -1;
        }
    #endif
    }

    /* Set wolfCrypt RSA key data from external if not already done. */
    if ((ret == 0) && (!rsa->inSet) && (SetRsaInternal(rsa) != 1)) {
        ret = -1;
    }

    if (ret == 0) {
        /* Calculate maximum length of decrypted data. */
        outLen = wolfSSL_RSA_size(rsa);
        if (outLen == 0) {
            WOLFSSL_ERROR_MSG("Bad RSA size");
            ret = -1;
        }
    }

    if (ret == 0) {
        /* Use wolfCrypt to private-decrypt with RSA key.
         * Size of 'to' buffer must be size of RSA key */
    #if !defined(HAVE_FIPS)
        ret = wc_RsaPrivateDecrypt_ex(from, (word32)len, to, (word32)outLen,
            (RsaKey*)rsa->internal, pad_type, hash, mgf, NULL, 0);
    #else
        ret = wc_RsaPrivateDecrypt(from, (word32)len, to, (word32)outLen,
            (RsaKey*)rsa->internal);
    #endif
    }

    /* wolfCrypt error means return -1. */
    if (ret <= 0) {
        ret = -1;
    }
    WOLFSSL_LEAVE("wolfSSL_RSA_private_decrypt", ret);
    return ret;
}

/* Decrypt with the RSA public key.
 *
 * @param [in]  len      Length of encrypted data.
 * @param [in]  from     Encrypted data.
 * @param [out] to       Decrypted data.
 * @param [in]  rsa      RSA key.
 * @param [in]  padding  Type of padding to around plaintext to remove.
 * @return  Size of decrypted data on success.
 * @return  -1 on failure.
 */
int wolfSSL_RSA_public_decrypt(int len, const unsigned char* from,
    unsigned char* to, WOLFSSL_RSA* rsa, int padding)
{
    int ret = 0;
#if !defined(HAVE_SELFTEST) && (!defined(HAVE_FIPS) || FIPS_VERSION_GT(2,0))
    int pad_type = WC_RSA_NO_PAD;
#endif
    int outLen = 0;

    WOLFSSL_ENTER("wolfSSL_RSA_public_decrypt");

    /* Validate parameters. */
    if ((len < 0) || (rsa == NULL) || (rsa->internal == NULL) ||
            (from == NULL)) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = -1;
    }

    if (ret == 0) {
    #if !defined(HAVE_SELFTEST) && (!defined(HAVE_FIPS) || FIPS_VERSION_GT(2,0))
        switch (padding) {
        case RSA_PKCS1_PADDING:
            pad_type = WC_RSA_PKCSV15_PAD;
            break;
        case RSA_NO_PADDING:
            pad_type = WC_RSA_NO_PAD;
            break;
        /* TODO: RSA_X931_PADDING not supported */
        default:
            WOLFSSL_ERROR_MSG("RSA_public_decrypt unsupported padding");
            ret = -1;
        }
    #else
        if (padding != RSA_PKCS1_PADDING) {
            WOLFSSL_ERROR_MSG("RSA_public_decrypt pad type not supported in "
                              "FIPS");
            ret = -1;
        }
    #endif
    }

    /* Set wolfCrypt RSA key data from external if not already done. */
    if ((ret == 0) && (!rsa->inSet) && (SetRsaInternal(rsa) != 1)) {
        ret = -1;
    }

    if (ret == 0) {
        /* Calculate maximum length of encrypted data. */
        outLen = wolfSSL_RSA_size(rsa);
        if (outLen == 0) {
            WOLFSSL_ERROR_MSG("Bad RSA size");
            ret = -1;
        }
    }

    if (ret == 0) {
        /* Use wolfCrypt to public-decrypt with RSA key. */
    #if !defined(HAVE_SELFTEST) && (!defined(HAVE_FIPS) || FIPS_VERSION_GT(2,0))
        /* Size of 'to' buffer must be size of RSA key. */
        ret = wc_RsaSSL_Verify_ex(from, (word32)len, to, (word32)outLen,
            (RsaKey*)rsa->internal, pad_type);
    #else
        /* For FIPS v1/v2 only PKCSV15 padding is supported */
        ret = wc_RsaSSL_Verify(from, (word32)len, to, (word32)outLen,
            (RsaKey*)rsa->internal);
    #endif
    }

    /* wolfCrypt error means return -1. */
    if (ret <= 0) {
        ret = -1;
    }
    WOLFSSL_LEAVE("wolfSSL_RSA_public_decrypt", ret);
    return ret;
}

/* Encrypt with the RSA private key.
 *
 * Calls wc_RsaSSL_Sign.
 *
 * @param [in]  len      Length of data to encrypt.
 * @param [in]  from     Data to encrypt.
 * @param [out] to       Encrypted data.
 * @param [in]  rsa      RSA key.
 * @param [in]  padding  Type of padding to place around plaintext.
 * @return  Size of encrypted data on success.
 * @return  -1 on failure.
 */
int wolfSSL_RSA_private_encrypt(int len, const unsigned char* from,
    unsigned char* to, WOLFSSL_RSA* rsa, int padding)
{
    int ret = 0;
    int initTmpRng = 0;
    WC_RNG *rng = NULL;
#ifdef WOLFSSL_SMALL_STACK
    WC_RNG* tmpRng = NULL;
#else
    WC_RNG  _tmpRng[1];
    WC_RNG* tmpRng = _tmpRng;
#endif

    WOLFSSL_ENTER("wolfSSL_RSA_private_encrypt");

    /* Validate parameters. */
    if ((len < 0) || (rsa == NULL) || (rsa->internal == NULL) ||
            (from == NULL)) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = -1;
    }

    if (ret == 0) {
        switch (padding) {
        case RSA_PKCS1_PADDING:
    #ifdef WC_RSA_NO_PADDING
        case RSA_NO_PADDING:
    #endif
            break;
        /* TODO: RSA_X931_PADDING not supported */
        default:
            WOLFSSL_ERROR_MSG("RSA_private_encrypt unsupported padding");
            ret = -1;
        }
    }

    /* Set wolfCrypt RSA key data from external if not already done. */
    if ((ret == 0) && (!rsa->inSet) && (SetRsaInternal(rsa) != 1)) {
        ret = -1;
    }

    if (ret == 0) {
        /* Get an RNG. */
        rng = WOLFSSL_RSA_GetRNG(rsa, (WC_RNG**)&tmpRng, &initTmpRng);
        if (rng == NULL) {
            ret = -1;
        }
    }

    if (ret == 0) {
        /* Use wolfCrypt to private-encrypt with RSA key.
         * Size of output buffer must be size of RSA key. */
        if (padding == RSA_PKCS1_PADDING) {
            ret = wc_RsaSSL_Sign(from, (word32)len, to,
                (word32)wolfSSL_RSA_size(rsa), (RsaKey*)rsa->internal, rng);
        }
    #ifdef WC_RSA_NO_PADDING
        else if (padding == RSA_NO_PADDING) {
            word32 outLen = (word32)wolfSSL_RSA_size(rsa);
            ret = wc_RsaFunction(from, (word32)len, to, &outLen,
                    RSA_PRIVATE_ENCRYPT, (RsaKey*)rsa->internal, rng);
            if (ret == 0)
                ret = (int)outLen;
        }
    #endif
    }

    /* Finalize RNG if initialized in WOLFSSL_RSA_GetRNG(). */
    if (initTmpRng) {
        wc_FreeRng(tmpRng);
    }
#ifdef WOLFSSL_SMALL_STACK
    /* Dispose of any allocated RNG. */
    XFREE(tmpRng, NULL, DYNAMIC_TYPE_RNG);
#endif

    /* wolfCrypt error means return -1. */
    if (ret <= 0) {
        ret = -1;
    }
    WOLFSSL_LEAVE("wolfSSL_RSA_private_encrypt", ret);
    return ret;
}

/*
 * RSA misc operation APIs
 */

/* Calculate d mod p-1 and q-1 into BNs.
 *
 * Not OpenSSL API.
 *
 * @param [in, out] rsa  RSA key.
 * @return 1 on success.
 * @return -1 on failure.
 */
int wolfSSL_RSA_GenAdd(WOLFSSL_RSA* rsa)
{
    int     ret = 1;
    int     err;
    mp_int* t = NULL;
#ifdef WOLFSSL_SMALL_STACK
    mp_int  *tmp = NULL;
#else
    mp_int  tmp[1];
#endif

    WOLFSSL_ENTER("wolfSSL_RsaGenAdd");

    /* Validate parameters. */
    if ((rsa == NULL) || (rsa->p == NULL) || (rsa->q == NULL) ||
            (rsa->d == NULL) || (rsa->dmp1 == NULL) || (rsa->dmq1 == NULL)) {
        WOLFSSL_ERROR_MSG("rsa no init error");
        ret = -1;
    }

#ifdef WOLFSSL_SMALL_STACK
    if (ret == 1) {
        tmp = (mp_int *)XMALLOC(sizeof(*tmp), rsa->heap,
                                     DYNAMIC_TYPE_TMP_BUFFER);
        if (tmp == NULL) {
            WOLFSSL_ERROR_MSG("Memory allocation failure");
            ret = -1;
        }
    }
#endif

    if (ret == 1) {
        /* Initialize temp MP integer. */
        if (mp_init(tmp) != MP_OKAY) {
            WOLFSSL_ERROR_MSG("mp_init error");
            ret = -1;
        }
    }

    if (ret == 1) {
        t = tmp;

        /* Sub 1 from p into temp. */
        err = mp_sub_d((mp_int*)rsa->p->internal, 1, tmp);
        if (err != MP_OKAY) {
            WOLFSSL_ERROR_MSG("mp_sub_d error");
            ret = -1;
        }
    }
    if (ret == 1) {
        /* Calculate d mod (p - 1) into dmp1 MP integer of BN. */
        err = mp_mod((mp_int*)rsa->d->internal, tmp,
            (mp_int*)rsa->dmp1->internal);
        if (err != MP_OKAY) {
            WOLFSSL_ERROR_MSG("mp_mod error");
            ret = -1;
        }
    }
    if (ret == 1) {
        /* Sub 1 from q into temp. */
        err = mp_sub_d((mp_int*)rsa->q->internal, 1, tmp);
        if (err != MP_OKAY) {
            WOLFSSL_ERROR_MSG("mp_sub_d error");
            ret = -1;
        }
    }
    if (ret == 1) {
        /* Calculate d mod (q - 1) into dmq1 MP integer of BN. */
        err = mp_mod((mp_int*)rsa->d->internal, tmp,
            (mp_int*)rsa->dmq1->internal);
        if (err != MP_OKAY) {
            WOLFSSL_ERROR_MSG("mp_mod error");
            ret = -1;
        }
    }

    mp_clear(t);

#ifdef WOLFSSL_SMALL_STACK
    if (tmp != NULL)
        XFREE(tmp, rsa->heap, DYNAMIC_TYPE_TMP_BUFFER);
#endif

    return ret;
}


#ifndef NO_WOLFSSL_STUB
/* Enable blinding for RSA key operations.
 *
 * Blinding is a compile time option in wolfCrypt.
 *
 * @param [in] rsa    RSA key. Unused.
 * @param [in] bnCtx  BN context to use for blinding. Unused.
 * @return 1 always.
 */
int wolfSSL_RSA_blinding_on(WOLFSSL_RSA* rsa, WOLFSSL_BN_CTX* bnCtx)
{
    WOLFSSL_STUB("RSA_blinding_on");
    WOLFSSL_ENTER("wolfSSL_RSA_blinding_on");

    (void)rsa;
    (void)bnCtx;

    return 1;  /* on by default */
}
#endif

#endif /* OPENSSL_EXTRA */

#endif /* !NO_RSA */

/*******************************************************************************
 * END OF RSA API
 ******************************************************************************/


/*******************************************************************************
 * START OF DSA API
 ******************************************************************************/

#ifndef NO_DSA

#if defined(OPENSSL_EXTRA) && defined(XFPRINTF) && !defined(NO_FILESYSTEM) && \
    !defined(NO_STDIO_FILESYSTEM)
/* return code compliant with OpenSSL :
 *   1 if success, 0 if error
 */
int wolfSSL_DSA_print_fp(XFILE fp, WOLFSSL_DSA* dsa, int indent)
{
    int ret = 1;

    WOLFSSL_ENTER("wolfSSL_DSA_print_fp");

    if (fp == XBADFILE || dsa == NULL) {
        ret = 0;
    }

    if (ret == 1 && dsa->p != NULL) {
        int pBits = wolfSSL_BN_num_bits(dsa->p);
        if (pBits == 0) {
            ret = 0;
        }
        else {
            if (XFPRINTF(fp, "%*s", indent, "") < 0)
                ret = 0;
            else if (XFPRINTF(fp, "Private-Key: (%d bit)\n", pBits) < 0)
                ret = 0;
        }
    }
    if (ret == 1 && dsa->priv_key != NULL) {
        ret = pk_bn_field_print_fp(fp, indent, "priv", dsa->priv_key);
    }
    if (ret == 1 && dsa->pub_key != NULL) {
        ret = pk_bn_field_print_fp(fp, indent, "pub", dsa->pub_key);
    }
    if (ret == 1 && dsa->p != NULL) {
        ret = pk_bn_field_print_fp(fp, indent, "P", dsa->p);
    }
    if (ret == 1 && dsa->q != NULL) {
        ret = pk_bn_field_print_fp(fp, indent, "Q", dsa->q);
    }
    if (ret == 1 && dsa->g != NULL) {
        ret = pk_bn_field_print_fp(fp, indent, "G", dsa->g);
    }

    WOLFSSL_LEAVE("wolfSSL_DSA_print_fp", ret);

    return ret;
}
#endif /* OPENSSL_EXTRA && XSNPRINTF && !NO_FILESYSTEM && NO_STDIO_FILESYSTEM */

#if defined(OPENSSL_EXTRA) || defined(OPENSSL_EXTRA_X509_SMALL)
static void InitwolfSSL_DSA(WOLFSSL_DSA* dsa)
{
    if (dsa) {
        dsa->p        = NULL;
        dsa->q        = NULL;
        dsa->g        = NULL;
        dsa->pub_key  = NULL;
        dsa->priv_key = NULL;
        dsa->internal = NULL;
        dsa->inSet    = 0;
        dsa->exSet    = 0;
    }
}


WOLFSSL_DSA* wolfSSL_DSA_new(void)
{
    WOLFSSL_DSA* external;
    DsaKey*     key;

    WOLFSSL_MSG("wolfSSL_DSA_new");

    key = (DsaKey*) XMALLOC(sizeof(DsaKey), NULL, DYNAMIC_TYPE_DSA);
    if (key == NULL) {
        WOLFSSL_MSG("wolfSSL_DSA_new malloc DsaKey failure");
        return NULL;
    }

    external = (WOLFSSL_DSA*) XMALLOC(sizeof(WOLFSSL_DSA), NULL,
                                    DYNAMIC_TYPE_DSA);
    if (external == NULL) {
        WOLFSSL_MSG("wolfSSL_DSA_new malloc WOLFSSL_DSA failure");
        XFREE(key, NULL, DYNAMIC_TYPE_DSA);
        return NULL;
    }

    InitwolfSSL_DSA(external);
    if (wc_InitDsaKey(key) != 0) {
        WOLFSSL_MSG("wolfSSL_DSA_new InitDsaKey failure");
        XFREE(key, NULL, DYNAMIC_TYPE_DSA);
        wolfSSL_DSA_free(external);
        return NULL;
    }
    external->internal = key;

    return external;
}


void wolfSSL_DSA_free(WOLFSSL_DSA* dsa)
{
    WOLFSSL_MSG("wolfSSL_DSA_free");

    if (dsa) {
        if (dsa->internal) {
            FreeDsaKey((DsaKey*)dsa->internal);
            XFREE(dsa->internal, NULL, DYNAMIC_TYPE_DSA);
            dsa->internal = NULL;
        }
        wolfSSL_BN_free(dsa->priv_key);
        wolfSSL_BN_free(dsa->pub_key);
        wolfSSL_BN_free(dsa->g);
        wolfSSL_BN_free(dsa->q);
        wolfSSL_BN_free(dsa->p);
        InitwolfSSL_DSA(dsa);  /* set back to NULLs for safety */

        XFREE(dsa, NULL, DYNAMIC_TYPE_DSA);

        /* dsa = NULL, don't try to access or double free it */
    }
}

/* wolfSSL -> OpenSSL */
int SetDsaExternal(WOLFSSL_DSA* dsa)
{
    DsaKey* key;
    WOLFSSL_MSG("Entering SetDsaExternal");

    if (dsa == NULL || dsa->internal == NULL) {
        WOLFSSL_MSG("dsa key NULL error");
        return -1;
    }

    key = (DsaKey*)dsa->internal;

    if (wolfssl_bn_set_value(&dsa->p, &key->p) != 1) {
        WOLFSSL_MSG("dsa p key error");
        return -1;
    }

    if (wolfssl_bn_set_value(&dsa->q, &key->q) != 1) {
        WOLFSSL_MSG("dsa q key error");
        return -1;
    }

    if (wolfssl_bn_set_value(&dsa->g, &key->g) != 1) {
        WOLFSSL_MSG("dsa g key error");
        return -1;
    }

    if (wolfssl_bn_set_value(&dsa->pub_key, &key->y) != 1) {
        WOLFSSL_MSG("dsa y key error");
        return -1;
    }

    if (wolfssl_bn_set_value(&dsa->priv_key, &key->x) != 1) {
        WOLFSSL_MSG("dsa x key error");
        return -1;
    }

    dsa->exSet = 1;

    return 1;
}
#endif /* OPENSSL_EXTRA || OPENSSL_EXTRA_X509_SMALL */

#ifdef OPENSSL_EXTRA
/* Openssl -> WolfSSL */
int SetDsaInternal(WOLFSSL_DSA* dsa)
{
    DsaKey* key;
    WOLFSSL_MSG("Entering SetDsaInternal");

    if (dsa == NULL || dsa->internal == NULL) {
        WOLFSSL_MSG("dsa key NULL error");
        return -1;
    }

    key = (DsaKey*)dsa->internal;

    if (dsa->p != NULL &&
        wolfssl_bn_get_value(dsa->p, &key->p) != 1) {
        WOLFSSL_MSG("rsa p key error");
        return -1;
    }

    if (dsa->q != NULL &&
        wolfssl_bn_get_value(dsa->q, &key->q) != 1) {
        WOLFSSL_MSG("rsa q key error");
        return -1;
    }

    if (dsa->g != NULL &&
        wolfssl_bn_get_value(dsa->g, &key->g) != 1) {
        WOLFSSL_MSG("rsa g key error");
        return -1;
    }

    if (dsa->pub_key != NULL) {
        if (wolfssl_bn_get_value(dsa->pub_key, &key->y) != 1) {
            WOLFSSL_MSG("rsa pub_key error");
            return -1;
        }

        /* public key */
        key->type = DSA_PUBLIC;
    }

    if (dsa->priv_key != NULL) {
        if (wolfssl_bn_get_value(dsa->priv_key, &key->x) != 1) {
            WOLFSSL_MSG("rsa priv_key error");
            return -1;
        }

        /* private key */
        key->type = DSA_PRIVATE;
    }

    dsa->inSet = 1;

    return 1;
}

/* return code compliant with OpenSSL :
 *   1 if success, 0 if error
 */
int wolfSSL_DSA_generate_key(WOLFSSL_DSA* dsa)
{
    int ret = 0;

    WOLFSSL_ENTER("wolfSSL_DSA_generate_key");

    if (dsa == NULL || dsa->internal == NULL) {
        WOLFSSL_MSG("Bad arguments");
        return 0;
    }

    if (dsa->inSet == 0) {
        WOLFSSL_MSG("No DSA internal set, do it");

        if (SetDsaInternal(dsa) != 1) {
            WOLFSSL_MSG("SetDsaInternal failed");
            return ret;
        }
    }

#ifdef WOLFSSL_KEY_GEN
    {
        int initTmpRng = 0;
        WC_RNG *rng = NULL;
#ifdef WOLFSSL_SMALL_STACK
        WC_RNG *tmpRng;
#else
        WC_RNG tmpRng[1];
#endif

#ifdef WOLFSSL_SMALL_STACK
        tmpRng = (WC_RNG*)XMALLOC(sizeof(WC_RNG), NULL, DYNAMIC_TYPE_RNG);
        if (tmpRng == NULL)
            return -1;
#endif
        if (wc_InitRng(tmpRng) == 0) {
            rng = tmpRng;
            initTmpRng = 1;
        }
        else {
            WOLFSSL_MSG("Bad RNG Init, trying global");
            rng = wolfssl_get_global_rng();
        }

        if (rng) {
            /* These were allocated above by SetDsaInternal(). They should
             * be cleared before wc_MakeDsaKey() which reinitializes
             * x and y. */
            mp_clear(&((DsaKey*)dsa->internal)->x);
            mp_clear(&((DsaKey*)dsa->internal)->y);

            if (wc_MakeDsaKey(rng, (DsaKey*)dsa->internal) != MP_OKAY)
                WOLFSSL_MSG("wc_MakeDsaKey failed");
            else if (SetDsaExternal(dsa) != 1)
                WOLFSSL_MSG("SetDsaExternal failed");
            else
                ret = 1;
        }

        if (initTmpRng)
            wc_FreeRng(tmpRng);

#ifdef WOLFSSL_SMALL_STACK
        XFREE(tmpRng, NULL, DYNAMIC_TYPE_RNG);
#endif
    }
#else /* WOLFSSL_KEY_GEN */
    WOLFSSL_MSG("No Key Gen built in");
#endif
    return ret;
}


/* Returns a pointer to a new WOLFSSL_DSA structure on success and NULL on fail
 */
WOLFSSL_DSA* wolfSSL_DSA_generate_parameters(int bits, unsigned char* seed,
        int seedLen, int* counterRet, unsigned long* hRet,
        WOLFSSL_BN_CB cb, void* CBArg)
{
    WOLFSSL_DSA* dsa;

    WOLFSSL_ENTER("wolfSSL_DSA_generate_parameters");

    (void)cb;
    (void)CBArg;
    dsa = wolfSSL_DSA_new();
    if (dsa == NULL) {
        return NULL;
    }

    if (wolfSSL_DSA_generate_parameters_ex(dsa, bits, seed, seedLen,
                                  counterRet, hRet, NULL) != 1) {
        wolfSSL_DSA_free(dsa);
        return NULL;
    }

    return dsa;
}


/* return code compliant with OpenSSL :
 *   1 if success, 0 if error
 */
int wolfSSL_DSA_generate_parameters_ex(WOLFSSL_DSA* dsa, int bits,
                                       unsigned char* seed, int seedLen,
                                       int* counterRet,
                                       unsigned long* hRet, void* cb)
{
    int ret = 0;

    (void)bits;
    (void)seed;
    (void)seedLen;
    (void)counterRet;
    (void)hRet;
    (void)cb;

    WOLFSSL_ENTER("wolfSSL_DSA_generate_parameters_ex");

    if (dsa == NULL || dsa->internal == NULL) {
        WOLFSSL_MSG("Bad arguments");
        return 0;
    }

#ifdef WOLFSSL_KEY_GEN
    {
        int initTmpRng = 0;
        WC_RNG *rng = NULL;
#ifdef WOLFSSL_SMALL_STACK
        WC_RNG *tmpRng;
#else
        WC_RNG tmpRng[1];
#endif

#ifdef WOLFSSL_SMALL_STACK
        tmpRng = (WC_RNG*)XMALLOC(sizeof(WC_RNG), NULL, DYNAMIC_TYPE_RNG);
        if (tmpRng == NULL)
            return -1;
#endif
        if (wc_InitRng(tmpRng) == 0) {
            rng = tmpRng;
            initTmpRng = 1;
        }
        else {
            WOLFSSL_MSG("Bad RNG Init, trying global");
            rng = wolfssl_get_global_rng();
        }

        if (rng) {
            if (wc_MakeDsaParameters(rng, bits,
                                     (DsaKey*)dsa->internal) != MP_OKAY)
                WOLFSSL_MSG("wc_MakeDsaParameters failed");
            else if (SetDsaExternal(dsa) != 1)
                WOLFSSL_MSG("SetDsaExternal failed");
            else
                ret = 1;
        }

        if (initTmpRng)
            wc_FreeRng(tmpRng);

#ifdef WOLFSSL_SMALL_STACK
        XFREE(tmpRng, NULL, DYNAMIC_TYPE_RNG);
#endif
    }
#else /* WOLFSSL_KEY_GEN */
    WOLFSSL_MSG("No Key Gen built in");
#endif

    return ret;
}

void wolfSSL_DSA_get0_pqg(const WOLFSSL_DSA *d, const WOLFSSL_BIGNUM **p,
        const WOLFSSL_BIGNUM **q, const WOLFSSL_BIGNUM **g)
{
    WOLFSSL_ENTER("wolfSSL_DSA_get0_pqg");
    if (d != NULL) {
        if (p != NULL)
            *p = d->p;
        if (q != NULL)
            *q = d->q;
        if (g != NULL)
            *g = d->g;
    }
}

int wolfSSL_DSA_set0_pqg(WOLFSSL_DSA *d, WOLFSSL_BIGNUM *p,
        WOLFSSL_BIGNUM *q, WOLFSSL_BIGNUM *g)
{
    WOLFSSL_ENTER("wolfSSL_DSA_set0_pqg");
    if (d == NULL || p == NULL || q == NULL || g == NULL) {
        WOLFSSL_MSG("Bad parameter");
        return 0;
    }
    wolfSSL_BN_free(d->p);
    wolfSSL_BN_free(d->q);
    wolfSSL_BN_free(d->g);
    d->p = p;
    d->q = q;
    d->g = g;
    return 1;
}

void wolfSSL_DSA_get0_key(const WOLFSSL_DSA *d,
        const WOLFSSL_BIGNUM **pub_key, const WOLFSSL_BIGNUM **priv_key)
{
    WOLFSSL_ENTER("wolfSSL_DSA_get0_key");
    if (d != NULL) {
        if (pub_key != NULL)
            *pub_key = d->pub_key;
        if (priv_key != NULL)
            *priv_key = d->priv_key;
    }
}

int wolfSSL_DSA_set0_key(WOLFSSL_DSA *d, WOLFSSL_BIGNUM *pub_key,
        WOLFSSL_BIGNUM *priv_key)
{
    WOLFSSL_ENTER("wolfSSL_DSA_set0_key");

    /* The private key may be NULL */
    if (d->pub_key == NULL && pub_key == NULL) {
        WOLFSSL_MSG("Bad parameter");
        return 0;
    }

    if (pub_key != NULL) {
        wolfSSL_BN_free(d->pub_key);
        d->pub_key = pub_key;
    }
    if (priv_key != NULL) {
        wolfSSL_BN_free(d->priv_key);
        d->priv_key = priv_key;
    }

    return 1;
}

WOLFSSL_DSA_SIG* wolfSSL_DSA_SIG_new(void)
{
    WOLFSSL_DSA_SIG* sig;
    WOLFSSL_ENTER("wolfSSL_DSA_SIG_new");
    sig = (WOLFSSL_DSA_SIG*)XMALLOC(sizeof(WOLFSSL_DSA_SIG), NULL,
        DYNAMIC_TYPE_OPENSSL);
    if (sig)
        XMEMSET(sig, 0, sizeof(WOLFSSL_DSA_SIG));
    return sig;
}

void wolfSSL_DSA_SIG_free(WOLFSSL_DSA_SIG *sig)
{
    WOLFSSL_ENTER("wolfSSL_DSA_SIG_free");
    if (sig) {
        if (sig->r) {
            wolfSSL_BN_free(sig->r);
        }
        if (sig->s) {
            wolfSSL_BN_free(sig->s);
        }
        XFREE(sig, NULL, DYNAMIC_TYPE_OPENSSL);
    }
}

void wolfSSL_DSA_SIG_get0(const WOLFSSL_DSA_SIG *sig,
        const WOLFSSL_BIGNUM **r, const WOLFSSL_BIGNUM **s)
{
    WOLFSSL_ENTER("wolfSSL_DSA_SIG_get0");
    if (sig != NULL) {
        *r = sig->r;
        *s = sig->s;
    }
}

int wolfSSL_DSA_SIG_set0(WOLFSSL_DSA_SIG *sig, WOLFSSL_BIGNUM *r,
        WOLFSSL_BIGNUM *s)
{
    WOLFSSL_ENTER("wolfSSL_DSA_SIG_set0");
    if (r == NULL || s == NULL) {
        WOLFSSL_MSG("Bad parameter");
        return 0;
    }

    wolfSSL_BN_clear_free(sig->r);
    wolfSSL_BN_clear_free(sig->s);
    sig->r = r;
    sig->s = s;

    return 1;
}

#ifndef HAVE_SELFTEST
/**
 *
 * @param sig The input signature to encode
 * @param out The output buffer. If *out is NULL then a new buffer is
 *            allocated. Otherwise the output is written to the buffer.
 * @return length on success and -1 on error
 */
int wolfSSL_i2d_DSA_SIG(const WOLFSSL_DSA_SIG *sig, byte **out)
{
    /* Space for sequence + two asn ints */
    byte buf[MAX_SEQ_SZ + 2*(ASN_TAG_SZ + MAX_LENGTH_SZ + DSA_MAX_HALF_SIZE)];
    word32 bufLen = sizeof(buf);

    WOLFSSL_ENTER("wolfSSL_i2d_DSA_SIG");

    if (sig == NULL || sig->r == NULL || sig->s == NULL ||
            out == NULL) {
        WOLFSSL_MSG("Bad function arguments");
        return -1;
    }

    if (StoreECC_DSA_Sig(buf, &bufLen,
            (mp_int*)sig->r->internal, (mp_int*)sig->s->internal) != 0) {
        WOLFSSL_MSG("StoreECC_DSA_Sig error");
        return -1;
    }

    if (*out == NULL) {
        byte* tmp = (byte*)XMALLOC(bufLen, NULL, DYNAMIC_TYPE_ASN1);
        if (tmp == NULL) {
            WOLFSSL_MSG("malloc error");
            return -1;
        }
        *out = tmp;
    }

   XMEMCPY(*out, buf, bufLen);

    return (int)bufLen;
}

/**
 * Same as wolfSSL_DSA_SIG_new but also initializes the internal bignums as well.
 * @return New WOLFSSL_DSA_SIG with r and s created as well
 */
static WOLFSSL_DSA_SIG* wolfSSL_DSA_SIG_new_bn(void)
{
    WOLFSSL_DSA_SIG* ret;

    if ((ret = wolfSSL_DSA_SIG_new()) == NULL) {
        WOLFSSL_MSG("wolfSSL_DSA_SIG_new error");
        return NULL;
    }

    if ((ret->r = wolfSSL_BN_new()) == NULL) {
        WOLFSSL_MSG("wolfSSL_BN_new error");
        wolfSSL_DSA_SIG_free(ret);
        return NULL;
    }

    if ((ret->s = wolfSSL_BN_new()) == NULL) {
        WOLFSSL_MSG("wolfSSL_BN_new error");
        wolfSSL_DSA_SIG_free(ret);
        return NULL;
    }

    return ret;
}

/**
 * This parses a DER encoded ASN.1 structure. The ASN.1 encoding is:
 * ASN1_SEQUENCE
 *   ASN1_INTEGER (DSA r)
 *   ASN1_INTEGER (DSA s)
 * Alternatively, if the input is DSA_160_SIG_SIZE or DSA_256_SIG_SIZE in
 * length then this API interprets this as two unsigned binary numbers.
 * @param sig    If non-null then free'd first and then newly created
 *               WOLFSSL_DSA_SIG is assigned
 * @param pp     Input buffer that is moved forward on success
 * @param length Length of input buffer
 * @return Newly created WOLFSSL_DSA_SIG on success or NULL on failure
 */
WOLFSSL_DSA_SIG* wolfSSL_d2i_DSA_SIG(WOLFSSL_DSA_SIG **sig,
        const unsigned char **pp, long length)
{
    WOLFSSL_DSA_SIG* ret;
    mp_int* r;
    mp_int* s;

    WOLFSSL_ENTER("wolfSSL_d2i_DSA_SIG");

    if (pp == NULL || *pp == NULL || length < 0) {
        WOLFSSL_MSG("Bad function arguments");
        return NULL;
    }

    if ((ret = wolfSSL_DSA_SIG_new_bn()) == NULL) {
        WOLFSSL_MSG("wolfSSL_DSA_SIG_new_bn error");
        return NULL;
    }

    r = (mp_int*)ret->r->internal;
    s = (mp_int*)ret->s->internal;

    if (DecodeECC_DSA_Sig(*pp, (word32)length, r, s) != 0) {
        if (length == DSA_160_SIG_SIZE || length == DSA_256_SIG_SIZE) {
            /* Two raw numbers of length/2 size each */
            if (mp_read_unsigned_bin(r, *pp, (word32)length/2) != 0) {
                WOLFSSL_MSG("r mp_read_unsigned_bin error");
                wolfSSL_DSA_SIG_free(ret);
                return NULL;
            }

            if (mp_read_unsigned_bin(s, *pp + (length/2), (word32)length/2) !=
                    0) {
                WOLFSSL_MSG("s mp_read_unsigned_bin error");
                wolfSSL_DSA_SIG_free(ret);
                return NULL;
            }

            *pp += length;
        }
        else {
            WOLFSSL_MSG("DecodeECC_DSA_Sig error");
            wolfSSL_DSA_SIG_free(ret);
            return NULL;
        }
    }
    else {
        /* DecodeECC_DSA_Sig success move pointer forward */
#ifndef NO_STRICT_ECDSA_LEN
        *pp += length;
#else
        {
            /* We need to figure out how much to move by ourselves */
            word32 idx = 0;
            int len = 0;
            if (GetSequence(*pp, &idx, &len, (word32)length) < 0) {
                WOLFSSL_MSG("GetSequence error");
                wolfSSL_DSA_SIG_free(ret);
                return NULL;
            }
            *pp += len;
        }
#endif
    }

    if (sig != NULL) {
        if (*sig != NULL)
            wolfSSL_DSA_SIG_free(*sig);
        *sig = ret;
    }

    return ret;
}
#endif /* HAVE_SELFTEST */

/* return 1 on success, < 0 otherwise */
int wolfSSL_DSA_do_sign(const unsigned char* d, unsigned char* sigRet,
                       WOLFSSL_DSA* dsa)
{
    int     ret = -1;
    int     initTmpRng = 0;
    WC_RNG* rng = NULL;
#ifdef WOLFSSL_SMALL_STACK
    WC_RNG* tmpRng = NULL;
#else
    WC_RNG  tmpRng[1];
#endif

    WOLFSSL_ENTER("wolfSSL_DSA_do_sign");

    if (d == NULL || sigRet == NULL || dsa == NULL) {
        WOLFSSL_MSG("Bad function arguments");
        return ret;
    }

    if (dsa->inSet == 0) {
        WOLFSSL_MSG("No DSA internal set, do it");
        if (SetDsaInternal(dsa) != 1) {
            WOLFSSL_MSG("SetDsaInternal failed");
            return ret;
        }
    }

#ifdef WOLFSSL_SMALL_STACK
    tmpRng = (WC_RNG*)XMALLOC(sizeof(WC_RNG), NULL, DYNAMIC_TYPE_RNG);
    if (tmpRng == NULL)
        return -1;
#endif

    if (wc_InitRng(tmpRng) == 0) {
        rng = tmpRng;
        initTmpRng = 1;
    }
    else {
        WOLFSSL_MSG("Bad RNG Init, trying global");
        rng = wolfssl_get_global_rng();
    }

    if (rng) {
        if (wc_DsaSign(d, sigRet, (DsaKey*)dsa->internal, rng) < 0)
            WOLFSSL_MSG("DsaSign failed");
        else
            ret = 1;
    }

    if (initTmpRng)
        wc_FreeRng(tmpRng);
#ifdef WOLFSSL_SMALL_STACK
    XFREE(tmpRng, NULL, DYNAMIC_TYPE_RNG);
#endif

    return ret;
}

#ifndef HAVE_SELFTEST
WOLFSSL_DSA_SIG* wolfSSL_DSA_do_sign_ex(const unsigned char* digest,
                                        int inLen, WOLFSSL_DSA* dsa)
{
    byte sigBin[DSA_MAX_SIG_SIZE];
    const byte *tmp = sigBin;
    int sigLen;

    WOLFSSL_ENTER("wolfSSL_DSA_do_sign_ex");

    if (!digest || !dsa || inLen != WC_SHA_DIGEST_SIZE) {
        WOLFSSL_MSG("Bad function arguments");
        return NULL;
    }

    if (wolfSSL_DSA_do_sign(digest, sigBin, dsa) != 1) {
        WOLFSSL_MSG("wolfSSL_DSA_do_sign error");
        return NULL;
    }

    if (dsa->internal == NULL) {
        WOLFSSL_MSG("dsa->internal is null");
        return NULL;
    }

    sigLen = mp_unsigned_bin_size(&((DsaKey*)dsa->internal)->q);
    if (sigLen <= 0) {
        WOLFSSL_MSG("mp_unsigned_bin_size error");
        return NULL;
    }

    /* 2 * sigLen for the two points r and s */
    return wolfSSL_d2i_DSA_SIG(NULL, &tmp, 2 * sigLen);
}
#endif /* !HAVE_SELFTEST */

int wolfSSL_DSA_do_verify(const unsigned char* d, unsigned char* sig,
                        WOLFSSL_DSA* dsa, int *dsacheck)
{
    int    ret = -1;

    WOLFSSL_ENTER("wolfSSL_DSA_do_verify");

    if (d == NULL || sig == NULL || dsa == NULL) {
        WOLFSSL_MSG("Bad function arguments");
        return -1;
    }
    if (dsa->inSet == 0)
    {
        WOLFSSL_MSG("No DSA internal set, do it");

        if (SetDsaInternal(dsa) != 1) {
            WOLFSSL_MSG("SetDsaInternal failed");
            return -1;
        }
    }

    ret = DsaVerify(d, sig, (DsaKey*)dsa->internal, dsacheck);
    if (ret != 0 || *dsacheck != 1) {
        WOLFSSL_MSG("DsaVerify failed");
        return ret;
    }

    return 1;
}


int wolfSSL_DSA_bits(const WOLFSSL_DSA *d)
{
    if (!d)
        return 0;
    if (!d->exSet && SetDsaExternal((WOLFSSL_DSA*)d) != 1)
        return 0;
    return wolfSSL_BN_num_bits(d->p);
}

#ifndef HAVE_SELFTEST
int wolfSSL_DSA_do_verify_ex(const unsigned char* digest, int digest_len,
                             WOLFSSL_DSA_SIG* sig, WOLFSSL_DSA* dsa)
{
    int dsacheck, sz;
    byte sigBin[DSA_MAX_SIG_SIZE];
    byte* sigBinPtr = sigBin;
    DsaKey* key;
    int qSz;

    WOLFSSL_ENTER("wolfSSL_DSA_do_verify_ex");

    if (!digest || !sig || !dsa || digest_len != WC_SHA_DIGEST_SIZE) {
        WOLFSSL_MSG("Bad function arguments");
        return 0;
    }

    if (!sig->r || !sig->s) {
        WOLFSSL_MSG("No signature found in DSA_SIG");
        return 0;
    }

    if (dsa->inSet == 0) {
        WOLFSSL_MSG("No DSA internal set, do it");
        if (SetDsaInternal(dsa) != 1) {
            WOLFSSL_MSG("SetDsaInternal failed");
            return 0;
        }
    }

    key = (DsaKey*)dsa->internal;

    if (key == NULL) {
        WOLFSSL_MSG("dsa->internal is null");
        return 0;
    }

    qSz = mp_unsigned_bin_size(&key->q);
    if (qSz < 0 || qSz > DSA_MAX_HALF_SIZE) {
        WOLFSSL_MSG("mp_unsigned_bin_size error");
        return 0;
    }

    /* read r */
    /* front pad with zeros */
    if ((sz = wolfSSL_BN_num_bytes(sig->r)) < 0 || sz > DSA_MAX_HALF_SIZE)
        return 0;
    while (sz++ < qSz)
        *sigBinPtr++ = 0;
    if (wolfSSL_BN_bn2bin(sig->r, sigBinPtr) == -1)
        return 0;

    /* Move to s */
    sigBinPtr = sigBin + qSz;

    /* read s */
    /* front pad with zeros */
    if ((sz = wolfSSL_BN_num_bytes(sig->s)) < 0 || sz > DSA_MAX_HALF_SIZE)
        return 0;
    while (sz++ < qSz)
        *sigBinPtr++ = 0;
    if (wolfSSL_BN_bn2bin(sig->s, sigBinPtr) == -1)
        return 0;

    if ((wolfSSL_DSA_do_verify(digest, sigBin, dsa, &dsacheck)
                                         != 1) || dsacheck != 1) {
        return 0;
    }

    return 1;
}
#endif /* !HAVE_SELFTEST */

int wolfSSL_i2d_DSAparams(const WOLFSSL_DSA* dsa,
    unsigned char** out)
{
    int ret = 0;
    word32 derLen = 0;
    int preAllocated = 1;
    DsaKey* key = NULL;

    WOLFSSL_ENTER("wolfSSL_i2d_DSAparams");

    if (dsa == NULL || dsa->internal == NULL || out == NULL) {
        ret = BAD_FUNC_ARG;
    }

    if (ret == 0) {
        key = (DsaKey*)dsa->internal;
        ret = wc_DsaKeyToParamsDer_ex(key, NULL, &derLen);
        if (ret == WC_NO_ERR_TRACE(LENGTH_ONLY_E)) {
            ret = 0;
        }
    }
    if (ret == 0 && *out == NULL) {
        /* If we're allocating out for the caller, we don't increment out just
           past the end of the DER buffer. If out is already allocated, we do.
           (OpenSSL convention) */
        preAllocated = 0;
        *out = (unsigned char*)XMALLOC(derLen, key->heap, DYNAMIC_TYPE_OPENSSL);
        if (*out == NULL) {
            ret = MEMORY_E;
        }
    }
    if (ret == 0) {
        ret = wc_DsaKeyToParamsDer_ex(key, *out, &derLen);
    }
    if (ret >= 0 && preAllocated == 1) {
        *out += derLen;
    }

    if (ret < 0 && preAllocated == 0) {
        XFREE(*out, key ? key->heap : NULL, DYNAMIC_TYPE_OPENSSL);
    }

    WOLFSSL_LEAVE("wolfSSL_i2d_DSAparams", ret);

    return ret;
}

WOLFSSL_DSA* wolfSSL_d2i_DSAparams(WOLFSSL_DSA** dsa, const unsigned char** der,
    long derLen)
{
    WOLFSSL_DSA* ret = NULL;
    int err = 0;
    word32 idx = 0;
    int asnLen;
    DsaKey* internalKey = NULL;

    WOLFSSL_ENTER("wolfSSL_d2i_DSAparams");

    if (der == NULL || *der == NULL || derLen <= 0) {
        err = 1;
    }
    if (err == 0) {
        ret = wolfSSL_DSA_new();
        err = ret == NULL;
    }
    if (err == 0) {
        err = GetSequence(*der, &idx, &asnLen, (word32)derLen) <= 0;
    }
    if (err == 0) {
        internalKey = (DsaKey*)ret->internal;
        err = GetInt(&internalKey->p, *der, &idx, (word32)derLen) != 0;
    }
    if (err == 0) {
        err = GetInt(&internalKey->q, *der, &idx, (word32)derLen) != 0;
    }
    if (err == 0) {
        err = GetInt(&internalKey->g, *der, &idx, (word32)derLen) != 0;
    }
    if (err == 0) {
        err = wolfssl_bn_set_value(&ret->p, &internalKey->p)
                != 1;
    }
    if (err == 0) {
        err = wolfssl_bn_set_value(&ret->q, &internalKey->q)
                != 1;
    }
    if (err == 0) {
        err = wolfssl_bn_set_value(&ret->g, &internalKey->g)
                != 1;
    }
    if (err == 0 && dsa != NULL) {
        *dsa = ret;
    }

    if (err != 0 && ret != NULL) {
        wolfSSL_DSA_free(ret);
        ret = NULL;
    }

    return ret;
}

#if defined(WOLFSSL_KEY_GEN)
#ifndef NO_BIO

/* Takes a DSA Privatekey and writes it out to a WOLFSSL_BIO
 * Returns 1 or 0
 */
int wolfSSL_PEM_write_bio_DSAPrivateKey(WOLFSSL_BIO* bio, WOLFSSL_DSA* dsa,
    const EVP_CIPHER* cipher, unsigned char* passwd, int passwdSz,
    wc_pem_password_cb* cb, void* arg)
{
    int ret = 1;
    byte *pem = NULL;
    int pLen = 0;

    WOLFSSL_ENTER("wolfSSL_PEM_write_bio_DSAPrivateKey");

    (void)cb;
    (void)arg;

    /* Validate parameters. */
    if ((bio == NULL) || (dsa == NULL)) {
        WOLFSSL_MSG("Bad Function Arguments");
        ret = 0;
    }

    if (ret == 1) {
        ret = wolfSSL_PEM_write_mem_DSAPrivateKey(dsa, cipher, passwd, passwdSz,
            &pem, &pLen);
    }

    /* Write PEM to BIO. */
    if ((ret == 1) && (wolfSSL_BIO_write(bio, pem, pLen) != pLen)) {
        WOLFSSL_ERROR_MSG("DSA private key BIO write failed");
        ret = 0;
    }

    XFREE(pem, NULL, DYNAMIC_TYPE_KEY);
    return ret;
}

#ifndef HAVE_SELFTEST
/* Encode the DSA public key as DER.
 *
 * @param [in]  key   DSA key to encode.
 * @param [out] der   Pointer through which buffer is returned.
 * @param [in]  heap  Heap hint.
 * @return  Size of encoding on success.
 * @return  0 on error.
 */
static int wolfssl_dsa_key_to_pubkey_der(WOLFSSL_DSA* key, unsigned char** der,
    void* heap)
{
    int sz;
    unsigned char* buf = NULL;

    /* Use maximum encoded size to allocate. */
    sz = MAX_DSA_PUBKEY_SZ;
    /* Allocate memory to hold encoding. */
    buf = (byte*)XMALLOC((size_t)sz, heap, DYNAMIC_TYPE_TMP_BUFFER);
    if (buf == NULL) {
        WOLFSSL_MSG("malloc failed");
        sz = 0;
    }
    if (sz > 0) {
        /* Encode public key to DER using wolfSSL.  */
        sz = wc_DsaKeyToPublicDer((DsaKey*)key->internal, buf, (word32)sz);
        if (sz < 0) {
            WOLFSSL_MSG("wc_DsaKeyToPublicDer failed");
            sz = 0;
        }
    }

    /* Return buffer on success. */
    if (sz > 0) {
        *der = buf;
    }
    else {
        /* Dispose of any dynamically allocated data not returned. */
        XFREE(buf, heap, DYNAMIC_TYPE_TMP_BUFFER);
    }

    return sz;
}

/* Takes a DSA public key and writes it out to a WOLFSSL_BIO
 * Returns 1 or 0
 */
int wolfSSL_PEM_write_bio_DSA_PUBKEY(WOLFSSL_BIO* bio, WOLFSSL_DSA* dsa)
{
    int ret = 1;
    unsigned char* derBuf = NULL;
    int derSz = 0;

    WOLFSSL_ENTER("wolfSSL_PEM_write_bio_DSA_PUBKEY");

    /* Validate parameters. */
    if ((bio == NULL) || (dsa == NULL)) {
        WOLFSSL_MSG("Bad Function Arguments");
        return 0;
    }

    /* Encode public key in EC key as DER. */
    derSz = wolfssl_dsa_key_to_pubkey_der(dsa, &derBuf, bio->heap);
    if (derSz == 0) {
        ret = 0;
    }

    /* Write out to BIO the PEM encoding of the DSA public key. */
    if ((ret == 1) && (der_write_to_bio_as_pem(derBuf, derSz, bio,
            PUBLICKEY_TYPE) != 1)) {
        ret = 0;
    }

    /* Dispose of any dynamically allocated data. */
    XFREE(derBuf, bio->heap, DYNAMIC_TYPE_TMP_BUFFER);

    return ret;
}
#endif /* HAVE_SELFTEST */
#endif /* !NO_BIO */

/* return code compliant with OpenSSL :
 *   1 if success, 0 if error
 */
int wolfSSL_PEM_write_mem_DSAPrivateKey(WOLFSSL_DSA* dsa,
                                        const EVP_CIPHER* cipher,
                                        unsigned char* passwd, int passwdSz,
                                        unsigned char **pem, int *pLen)
{
#if defined(WOLFSSL_PEM_TO_DER) || defined(WOLFSSL_DER_TO_PEM)
    byte *derBuf, *tmp, *cipherInfo = NULL;
    int  der_max_len = 0, derSz = 0;
    const int type = DSA_PRIVATEKEY_TYPE;
    const char* header = NULL;
    const char* footer = NULL;

    WOLFSSL_MSG("wolfSSL_PEM_write_mem_DSAPrivateKey");

    if (pem == NULL || pLen == NULL || dsa == NULL || dsa->internal == NULL) {
        WOLFSSL_MSG("Bad function arguments");
        return 0;
    }

    if (wc_PemGetHeaderFooter(type, &header, &footer) != 0)
        return 0;

    if (dsa->inSet == 0) {
        WOLFSSL_MSG("No DSA internal set, do it");

        if (SetDsaInternal(dsa) != 1) {
            WOLFSSL_MSG("SetDsaInternal failed");
            return 0;
        }
    }

    der_max_len = MAX_DSA_PRIVKEY_SZ;

    derBuf = (byte*)XMALLOC((size_t)der_max_len, NULL, DYNAMIC_TYPE_DER);
    if (derBuf == NULL) {
        WOLFSSL_MSG("malloc failed");
        return 0;
    }

    /* Key to DER */
    derSz = wc_DsaKeyToDer((DsaKey*)dsa->internal, derBuf, (word32)der_max_len);
    if (derSz < 0) {
        WOLFSSL_MSG("wc_DsaKeyToDer failed");
        XFREE(derBuf, NULL, DYNAMIC_TYPE_DER);
        return 0;
    }

    /* encrypt DER buffer if required */
    if (passwd != NULL && passwdSz > 0 && cipher != NULL) {
        int ret;

        ret = EncryptDerKey(derBuf, &derSz, cipher,
                            passwd, passwdSz, &cipherInfo, der_max_len);
        if (ret != 1) {
            WOLFSSL_MSG("EncryptDerKey failed");
            XFREE(derBuf, NULL, DYNAMIC_TYPE_DER);
            return ret;
        }
        /* tmp buffer with a max size */
        *pLen = (derSz * 2) + (int)XSTRLEN(header) + 1 +
            (int)XSTRLEN(footer) + 1 + HEADER_ENCRYPTED_KEY_SIZE;
    }
    else { /* tmp buffer with a max size */
        *pLen = (derSz * 2) + (int)XSTRLEN(header) + 1 +
            (int)XSTRLEN(footer) + 1;
    }

    tmp = (byte*)XMALLOC((size_t)*pLen, NULL, DYNAMIC_TYPE_PEM);
    if (tmp == NULL) {
        WOLFSSL_MSG("malloc failed");
        XFREE(derBuf, NULL, DYNAMIC_TYPE_DER);
        if (cipherInfo != NULL)
            XFREE(cipherInfo, NULL, DYNAMIC_TYPE_STRING);
        return 0;
    }

    /* DER to PEM */
    *pLen = wc_DerToPemEx(derBuf, (word32)derSz, tmp, (word32)*pLen, cipherInfo,
        type);
    if (*pLen <= 0) {
        WOLFSSL_MSG("wc_DerToPemEx failed");
        XFREE(derBuf, NULL, DYNAMIC_TYPE_DER);
        XFREE(tmp, NULL, DYNAMIC_TYPE_PEM);
        if (cipherInfo != NULL)
            XFREE(cipherInfo, NULL, DYNAMIC_TYPE_STRING);
        return 0;
    }
    XFREE(derBuf, NULL, DYNAMIC_TYPE_DER);
    if (cipherInfo != NULL)
        XFREE(cipherInfo, NULL, DYNAMIC_TYPE_STRING);

    *pem = (byte*)XMALLOC((size_t)((*pLen)+1), NULL, DYNAMIC_TYPE_KEY);
    if (*pem == NULL) {
        WOLFSSL_MSG("malloc failed");
        XFREE(tmp, NULL, DYNAMIC_TYPE_PEM);
        return 0;
    }
    XMEMSET(*pem, 0, (size_t)((*pLen)+1));

    if (XMEMCPY(*pem, tmp, (size_t)*pLen) == NULL) {
        WOLFSSL_MSG("XMEMCPY failed");
        XFREE(pem, NULL, DYNAMIC_TYPE_KEY);
        XFREE(tmp, NULL, DYNAMIC_TYPE_PEM);
        return 0;
    }
    XFREE(tmp, NULL, DYNAMIC_TYPE_PEM);

    return 1;
#else
    (void)dsa;
    (void)cipher;
    (void)passwd;
    (void)passwdSz;
    (void)pem;
    (void)pLen;
    return 0;
#endif /* WOLFSSL_PEM_TO_DER || WOLFSSL_DER_TO_PEM */
}

#ifndef NO_FILESYSTEM
/* return code compliant with OpenSSL :
 *   1 if success, 0 if error
 */
int wolfSSL_PEM_write_DSAPrivateKey(XFILE fp, WOLFSSL_DSA *dsa,
                                    const EVP_CIPHER *enc,
                                    unsigned char *kstr, int klen,
                                    wc_pem_password_cb *cb, void *u)
{
    byte *pem;
    int  pLen, ret;

    (void)cb;
    (void)u;

    WOLFSSL_MSG("wolfSSL_PEM_write_DSAPrivateKey");

    if (fp == XBADFILE || dsa == NULL || dsa->internal == NULL) {
        WOLFSSL_MSG("Bad function arguments");
        return 0;
    }

    ret = wolfSSL_PEM_write_mem_DSAPrivateKey(dsa, enc, kstr, klen, &pem,
        &pLen);
    if (ret != 1) {
        WOLFSSL_MSG("wolfSSL_PEM_write_mem_DSAPrivateKey failed");
        return 0;
    }

    ret = (int)XFWRITE(pem, (size_t)pLen, 1, fp);
    if (ret != 1) {
        WOLFSSL_MSG("DSA private key file write failed");
        return 0;
    }

    XFREE(pem, NULL, DYNAMIC_TYPE_KEY);
    return 1;
}

#endif /* NO_FILESYSTEM */
#endif /* defined(WOLFSSL_KEY_GEN) */

#ifndef NO_FILESYSTEM
/* return code compliant with OpenSSL :
 *   1 if success, 0 if error
 */
#ifndef NO_WOLFSSL_STUB
int wolfSSL_PEM_write_DSA_PUBKEY(XFILE fp, WOLFSSL_DSA *x)
{
    (void)fp;
    (void)x;
    WOLFSSL_STUB("PEM_write_DSA_PUBKEY");
    WOLFSSL_MSG("wolfSSL_PEM_write_DSA_PUBKEY not implemented");

    return 0;
}
#endif
#endif /* NO_FILESYSTEM */

#ifndef NO_BIO

#if (defined(OPENSSL_EXTRA) || defined(OPENSSL_ALL)) && (!defined(NO_CERTS) && \
       !defined(NO_FILESYSTEM) && defined(WOLFSSL_KEY_GEN))
/* Uses the same format of input as wolfSSL_PEM_read_bio_PrivateKey but expects
 * the results to be an DSA key.
 *
 * bio  structure to read DSA private key from
 * dsa  if not null is then set to the result
 * cb   password callback for reading PEM
 * pass password string
 *
 * returns a pointer to a new WOLFSSL_DSA structure on success and NULL on fail
 */
WOLFSSL_DSA* wolfSSL_PEM_read_bio_DSAPrivateKey(WOLFSSL_BIO* bio,
                                                WOLFSSL_DSA** dsa,
                                                wc_pem_password_cb* cb,
                                                void* pass)
{
    WOLFSSL_EVP_PKEY* pkey = NULL;
    WOLFSSL_DSA* local;
    WOLFSSL_ENTER("wolfSSL_PEM_read_bio_DSAPrivateKey");


    pkey = wolfSSL_PEM_read_bio_PrivateKey(bio, NULL, cb, pass);
    if (pkey == NULL) {
        WOLFSSL_MSG("Error in PEM_read_bio_PrivateKey");
         return NULL;
     }
     /* Since the WOLFSSL_DSA structure is being taken from WOLFSSL_EVP_PKEY the
     * flag indicating that the WOLFSSL_DSA structure is owned should be FALSE
     * to avoid having it free'd */
    pkey->ownDsa = 0;
    local = pkey->dsa;
    if (dsa != NULL) {
        *dsa = local;
    }
     wolfSSL_EVP_PKEY_free(pkey);
    return local;
}

/* Reads an DSA public key from a WOLFSSL_BIO into a WOLFSSL_DSA.
 * Returns 1 or 0
 */
WOLFSSL_DSA *wolfSSL_PEM_read_bio_DSA_PUBKEY(WOLFSSL_BIO* bio,WOLFSSL_DSA** dsa,
                                             wc_pem_password_cb* cb, void* pass)
{
    WOLFSSL_EVP_PKEY* pkey;
    WOLFSSL_DSA* local;
    WOLFSSL_ENTER("wolfSSL_PEM_read_bio_DSA_PUBKEY");

    pkey = wolfSSL_PEM_read_bio_PUBKEY(bio, NULL, cb, pass);
    if (pkey == NULL) {
        WOLFSSL_MSG("wolfSSL_PEM_read_bio_PUBKEY failed");
        return NULL;
    }

    /* Since the WOLFSSL_DSA structure is being taken from WOLFSSL_EVP_PKEY the
     * flag indicating that the WOLFSSL_DSA structure is owned should be FALSE
     * to avoid having it free'd */
    pkey->ownDsa = 0;
    local = pkey->dsa;
    if (dsa != NULL) {
        *dsa = local;
    }

    wolfSSL_EVP_PKEY_free(pkey);
    return local;
}
#endif /* (OPENSSL_EXTRA || OPENSSL_ALL) && (!NO_CERTS &&
          !NO_FILESYSTEM && WOLFSSL_KEY_GEN) */

#endif /* NO_BIO */

#endif /* OPENSSL_EXTRA */

#if defined(OPENSSL_EXTRA) || defined(OPENSSL_EXTRA_X509_SMALL)
/* return 1 if success, -1 if error */
int wolfSSL_DSA_LoadDer(WOLFSSL_DSA* dsa, const unsigned char* derBuf, int derSz)
{
    word32 idx = 0;
    int    ret;

    WOLFSSL_ENTER("wolfSSL_DSA_LoadDer");

    if (dsa == NULL || dsa->internal == NULL || derBuf == NULL || derSz <= 0) {
        WOLFSSL_MSG("Bad function arguments");
        return -1;
    }

    ret = DsaPrivateKeyDecode(derBuf, &idx, (DsaKey*)dsa->internal,
        (word32)derSz);
    if (ret < 0) {
        WOLFSSL_MSG("DsaPrivateKeyDecode failed");
        return -1;
    }

    if (SetDsaExternal(dsa) != 1) {
        WOLFSSL_MSG("SetDsaExternal failed");
        return -1;
    }

    dsa->inSet = 1;

    return 1;
}

/* Loads DSA key from DER buffer. opt = DSA_LOAD_PRIVATE or DSA_LOAD_PUBLIC.
    returns 1 on success, or 0 on failure.  */
int wolfSSL_DSA_LoadDer_ex(WOLFSSL_DSA* dsa, const unsigned char* derBuf,
                                                            int derSz, int opt)
{
    word32 idx = 0;
    int    ret;

    WOLFSSL_ENTER("wolfSSL_DSA_LoadDer");

    if (dsa == NULL || dsa->internal == NULL || derBuf == NULL || derSz <= 0) {
        WOLFSSL_MSG("Bad function arguments");
        return -1;
    }

    if (opt == WOLFSSL_DSA_LOAD_PRIVATE) {
        ret = DsaPrivateKeyDecode(derBuf, &idx, (DsaKey*)dsa->internal,
            (word32)derSz);
    }
    else {
        ret = DsaPublicKeyDecode(derBuf, &idx, (DsaKey*)dsa->internal,
            (word32)derSz);
    }

    if (ret < 0 && opt == WOLFSSL_DSA_LOAD_PRIVATE) {
        WOLFSSL_ERROR_VERBOSE(ret);
        WOLFSSL_MSG("DsaPrivateKeyDecode failed");
        return -1;
    }
    else if (ret < 0 && opt == WOLFSSL_DSA_LOAD_PUBLIC) {
        WOLFSSL_ERROR_VERBOSE(ret);
        WOLFSSL_MSG("DsaPublicKeyDecode failed");
        return -1;
    }

    if (SetDsaExternal(dsa) != 1) {
        WOLFSSL_MSG("SetDsaExternal failed");
        return -1;
    }

    dsa->inSet = 1;

    return 1;
}
#endif /* OPENSSL_EXTRA || OPENSSL_EXTRA_X509_SMALL */

#ifdef OPENSSL_EXTRA
#ifndef NO_BIO
WOLFSSL_DSA *wolfSSL_PEM_read_bio_DSAparams(WOLFSSL_BIO *bp, WOLFSSL_DSA **x,
        wc_pem_password_cb *cb, void *u)
{
    WOLFSSL_DSA* dsa;
    DsaKey* key;
    int    length;
    unsigned char*  buf;
    word32 bufSz;
    int ret;
    word32 idx = 0;
    DerBuffer* pDer;

    WOLFSSL_ENTER("wolfSSL_PEM_read_bio_DSAparams");

    ret = wolfSSL_BIO_get_mem_data(bp, &buf);
    if (ret <= 0) {
        WOLFSSL_LEAVE("wolfSSL_PEM_read_bio_DSAparams", ret);
        return NULL;
    }

    bufSz = (word32)ret;

    if (cb != NULL || u != NULL) {
        /*
         * cb is for a call back when encountering encrypted PEM files
         * if cb == NULL and u != NULL then u = null terminated password string
         */
        WOLFSSL_MSG("Not yet supporting call back or password for encrypted PEM");
    }

    if (PemToDer(buf, (long)bufSz, DSA_PARAM_TYPE, &pDer, NULL, NULL,
                    NULL) < 0 ) {
        WOLFSSL_MSG("Issue converting from PEM to DER");
        return NULL;
    }

    if (GetSequence(pDer->buffer, &idx, &length, pDer->length) < 0) {
        WOLFSSL_LEAVE("wolfSSL_PEM_read_bio_DSAparams", ret);
        FreeDer(&pDer);
        return NULL;
    }

    dsa = wolfSSL_DSA_new();
    if (dsa == NULL) {
        FreeDer(&pDer);
        WOLFSSL_MSG("Error creating DSA struct");
        return NULL;
    }

    key = (DsaKey*)dsa->internal;
    if (key == NULL) {
        FreeDer(&pDer);
        wolfSSL_DSA_free(dsa);
        WOLFSSL_MSG("Error finding DSA key struct");
        return NULL;
    }

    if (GetInt(&key->p,  pDer->buffer, &idx, pDer->length) < 0 ||
        GetInt(&key->q,  pDer->buffer, &idx, pDer->length) < 0 ||
        GetInt(&key->g,  pDer->buffer, &idx, pDer->length) < 0 ) {
        WOLFSSL_MSG("dsa key error");
        FreeDer(&pDer);
        wolfSSL_DSA_free(dsa);
        return NULL;
    }

    if (wolfssl_bn_set_value(&dsa->p, &key->p) != 1) {
        WOLFSSL_MSG("dsa p key error");
        FreeDer(&pDer);
        wolfSSL_DSA_free(dsa);
        return NULL;
    }

    if (wolfssl_bn_set_value(&dsa->q, &key->q) != 1) {
        WOLFSSL_MSG("dsa q key error");
        FreeDer(&pDer);
        wolfSSL_DSA_free(dsa);
        return NULL;
    }

    if (wolfssl_bn_set_value(&dsa->g, &key->g) != 1) {
        WOLFSSL_MSG("dsa g key error");
        FreeDer(&pDer);
        wolfSSL_DSA_free(dsa);
        return NULL;
    }

    if (x != NULL) {
        *x = dsa;
    }

    FreeDer(&pDer);
    return dsa;
}
#endif /* !NO_BIO */

#if !defined(NO_DH)
WOLFSSL_DH *wolfSSL_DSA_dup_DH(const WOLFSSL_DSA *dsa)
{
    WOLFSSL_DH* dh;
    DhKey*      key;

    WOLFSSL_ENTER("wolfSSL_DSA_dup_DH");

    if (dsa == NULL) {
        return NULL;
    }

    dh = wolfSSL_DH_new();
    if (dh == NULL) {
        return NULL;
    }
    key = (DhKey*)dh->internal;

    if (dsa->p != NULL &&
        wolfssl_bn_get_value(((WOLFSSL_DSA*)dsa)->p, &key->p)
                                                           != 1) {
        WOLFSSL_MSG("rsa p key error");
        wolfSSL_DH_free(dh);
        return NULL;
    }
    if (dsa->g != NULL &&
        wolfssl_bn_get_value(((WOLFSSL_DSA*)dsa)->g, &key->g)
                                                           != 1) {
        WOLFSSL_MSG("rsa g key error");
        wolfSSL_DH_free(dh);
        return NULL;
    }

    if (wolfssl_bn_set_value(&dh->p, &key->p) != 1) {
        WOLFSSL_MSG("dsa p key error");
        wolfSSL_DH_free(dh);
        return NULL;
    }
    if (wolfssl_bn_set_value(&dh->g, &key->g) != 1) {
        WOLFSSL_MSG("dsa g key error");
        wolfSSL_DH_free(dh);
        return NULL;
    }

    return dh;
}
#endif /* !NO_DH */

#endif /* OPENSSL_EXTRA */

#endif /* !NO_DSA */

/*******************************************************************************
 * END OF DSA API
 ******************************************************************************/


/*******************************************************************************
 * START OF DH API
 ******************************************************************************/

#ifndef NO_DH

#ifdef OPENSSL_EXTRA

/*
 * DH constructor/deconstructor APIs
 */

/* Allocate and initialize a new DH key.
 *
 * @return  DH key on success.
 * @return  NULL on failure.
 */
WOLFSSL_DH* wolfSSL_DH_new(void)
{
    int err = 0;
    WOLFSSL_DH* dh = NULL;
    DhKey* key = NULL;

    WOLFSSL_ENTER("wolfSSL_DH_new");

    /* Allocate OpenSSL DH key. */
    dh = (WOLFSSL_DH*)XMALLOC(sizeof(WOLFSSL_DH), NULL, DYNAMIC_TYPE_DH);
    if (dh == NULL) {
        WOLFSSL_ERROR_MSG("wolfSSL_DH_new malloc WOLFSSL_DH failure");
        err = 1;
    }

    if (!err) {
        /* Clear key data. */
        XMEMSET(dh, 0, sizeof(WOLFSSL_DH));
        /* Initialize reference counting. */
        wolfSSL_RefInit(&dh->ref, &err);
#ifdef WOLFSSL_REFCNT_ERROR_RETURN
    }
    if (!err) {
#endif
        /* Allocate wolfSSL DH key. */
        key = (DhKey*)XMALLOC(sizeof(DhKey), NULL, DYNAMIC_TYPE_DH);
        if (key == NULL) {
            WOLFSSL_ERROR_MSG("wolfSSL_DH_new malloc DhKey failure");
            err = 1;
        }
    }
    if (!err) {
        /* Set and initialize wolfSSL DH key. */
        dh->internal = key;
        if (wc_InitDhKey(key) != 0) {
            WOLFSSL_ERROR_MSG("wolfSSL_DH_new InitDhKey failure");
            err = 1;
        }
    }

    if (err && (dh != NULL)) {
        /* Dispose of the allocated memory. */
        XFREE(key, NULL, DYNAMIC_TYPE_DH);
        wolfSSL_RefFree(&dh->ref);
        XFREE(dh, NULL, DYNAMIC_TYPE_DH);
        dh = NULL;
    }
    return dh;
}

#if defined(HAVE_PUBLIC_FFDHE) || (defined(HAVE_FIPS) && FIPS_VERSION_EQ(2,0))
/* Set the DH parameters based on the NID.
 *
 * @param [in, out] dh   DH key to set.
 * @param [in]      nid  Numeric ID of predefined DH parameters.
 * @return  0 on success.
 * @return  1 on failure.
 */
static int wolfssl_dh_set_nid(WOLFSSL_DH* dh, int nid)
{
    int err = 0;
    const DhParams* params = NULL;

    /* HAVE_PUBLIC_FFDHE not required to expose wc_Dh_ffdhe* functions in
     * FIPS v2 module */
    switch (nid) {
#ifdef HAVE_FFDHE_2048
    case NID_ffdhe2048:
        params = wc_Dh_ffdhe2048_Get();
        break;
#endif /* HAVE_FFDHE_2048 */
#ifdef HAVE_FFDHE_3072
    case NID_ffdhe3072:
        params = wc_Dh_ffdhe3072_Get();
        break;
#endif /* HAVE_FFDHE_3072 */
#ifdef HAVE_FFDHE_4096
    case NID_ffdhe4096:
        params = wc_Dh_ffdhe4096_Get();
        break;
#endif /* HAVE_FFDHE_4096 */
    default:
        break;
    }
    if (params == NULL) {
        WOLFSSL_ERROR_MSG("Unable to find DH params for nid.");
        err = 1;
    }

    if (!err) {
        /* Set prime from data retrieved. */
        dh->p = wolfSSL_BN_bin2bn(params->p, (int)params->p_len, NULL);
        if (dh->p == NULL) {
            WOLFSSL_ERROR_MSG("Error converting p hex to WOLFSSL_BIGNUM.");
            err = 1;
        }
    }
    if (!err) {
        /* Set generator from data retrieved. */
        dh->g = wolfSSL_BN_bin2bn(params->g, (int)params->g_len, NULL);
        if (dh->g == NULL) {
            WOLFSSL_ERROR_MSG("Error converting g hex to WOLFSSL_BIGNUM.");
            err = 1;
        }
    }
#ifdef HAVE_FFDHE_Q
    if (!err) {
        /* Set order from data retrieved. */
        dh->q = wolfSSL_BN_bin2bn(params->q, params->q_len, NULL);
        if (dh->q == NULL) {
            WOLFSSL_ERROR_MSG("Error converting q hex to WOLFSSL_BIGNUM.");
            err = 1;
        }
    }
#endif

    /* Synchronize the external into internal DH key's parameters. */
    if ((!err) && (SetDhInternal(dh) != 1)) {
        WOLFSSL_ERROR_MSG("Failed to set internal DH params.");
        err = 1;
    }
    if (!err) {
        /* External DH key parameters were set. */
        dh->exSet = 1;
    }

    if (err == 1) {
        /* Dispose of any external parameters. */
    #ifdef HAVE_FFDHE_Q
        wolfSSL_BN_free(dh->q);
        dh->q = NULL;
    #endif
        wolfSSL_BN_free(dh->p);
        dh->p = NULL;
        wolfSSL_BN_free(dh->g);
        dh->g = NULL;
    }

    return err;
}
#elif !defined(HAVE_PUBLIC_FFDHE) && (!defined(HAVE_FIPS) || \
      FIPS_VERSION_GT(2,0))
/* Set the DH parameters based on the NID.
 *
 * FIPS v2 and lower doesn't support wc_DhSetNamedKey.
 *
 * @param [in, out] dh   DH key to set.
 * @param [in]      nid  Numeric ID of predefined DH parameters.
 * @return  0 on success.
 * @return  1 on failure.
 */
static int wolfssl_dh_set_nid(WOLFSSL_DH* dh, int nid)
{
    int err = 0;
    int name = 0;
#ifdef HAVE_FFDHE_Q
    int elements = ELEMENT_P | ELEMENT_G | ELEMENT_Q;
#else
    int elements = ELEMENT_P | ELEMENT_G;
#endif /* HAVE_FFDHE_Q */

    switch (nid) {
#ifdef HAVE_FFDHE_2048
    case NID_ffdhe2048:
        name = WC_FFDHE_2048;
        break;
#endif /* HAVE_FFDHE_2048 */
#ifdef HAVE_FFDHE_3072
    case NID_ffdhe3072:
        name = WC_FFDHE_3072;
        break;
#endif /* HAVE_FFDHE_3072 */
#ifdef HAVE_FFDHE_4096
    case NID_ffdhe4096:
        name = WC_FFDHE_4096;
        break;
#endif /* HAVE_FFDHE_4096 */
    default:
        err = 1;
        WOLFSSL_ERROR_MSG("Unable to find DH params for nid.");
        break;
    }
    /* Set the internal DH key's parameters based on name. */
    if ((!err) && (wc_DhSetNamedKey((DhKey*)dh->internal, name) != 0)) {
        WOLFSSL_ERROR_MSG("wc_DhSetNamedKey failed.");
        err = 1;
    }
    /* Synchronize the internal into external DH key's parameters. */
    if (!err && (SetDhExternal_ex(dh, elements) != 1)) {
        WOLFSSL_ERROR_MSG("Failed to set external DH params.");
        err = 1;
    }

    return err;
}
#else
/* Set the DH parameters based on the NID.
 *
 * Pre-defined DH parameters not available.
 *
 * @param [in, out] dh   DH key to set.
 * @param [in]      nid  Numeric ID of predefined DH parameters.
 * @return  1 for failure.
 */
static int wolfssl_dh_set_nid(WOLFSSL_DH* dh, int nid)
{
    return 1;
}
#endif

/* Allocate and initialize a new DH key with the parameters based on the NID.
 *
 * @param [in] nid  Numeric ID of DH parameters.
 *
 * @return  DH key on success.
 * @return  NULL on failure.
 */
WOLFSSL_DH* wolfSSL_DH_new_by_nid(int nid)
{
    WOLFSSL_DH* dh = NULL;
    int err = 0;

    WOLFSSL_ENTER("wolfSSL_DH_new_by_nid");

    /* Allocate a new DH key. */
    dh = wolfSSL_DH_new();
    if (dh == NULL) {
        WOLFSSL_ERROR_MSG("Failed to create WOLFSSL_DH.");
        err = 1;
    }
    if (!err) {
        /* Set the parameters based on NID. */
        err = wolfssl_dh_set_nid(dh, nid);
    }

    if (err && (dh != NULL)) {
        /* Dispose of the key on failure to set. */
        wolfSSL_DH_free(dh);
        dh = NULL;
    }

    WOLFSSL_LEAVE("wolfSSL_DH_new_by_nid", err);

    return dh;
}

/* Dispose of DH key and allocated data.
 *
 * Cannot use dh after this call.
 *
 * @param [in] dh  DH key to free.
 */
void wolfSSL_DH_free(WOLFSSL_DH* dh)
{
    int doFree = 0;

    WOLFSSL_ENTER("wolfSSL_DH_free");

    if (dh != NULL) {
        int err;

        /* Only free if all references to it are done */
        wolfSSL_RefDec(&dh->ref, &doFree, &err);
        /* Ignore errors - doFree will be 0 on error. */
        (void)err;
    }
    if (doFree) {
        /* Dispose of allocated reference counting data. */
        wolfSSL_RefFree(&dh->ref);

        /* Dispose of wolfSSL DH key. */
        if (dh->internal) {
            wc_FreeDhKey((DhKey*)dh->internal);
            XFREE(dh->internal, NULL, DYNAMIC_TYPE_DH);
            dh->internal = NULL;
        }

        /* Dispose of any allocated BNs. */
        wolfSSL_BN_free(dh->priv_key);
        wolfSSL_BN_free(dh->pub_key);
        wolfSSL_BN_free(dh->g);
        wolfSSL_BN_free(dh->p);
        wolfSSL_BN_free(dh->q);
        /* Set back to NULLs for safety. */
        XMEMSET(dh, 0, sizeof(WOLFSSL_DH));

        XFREE(dh, NULL, DYNAMIC_TYPE_DH);
    }
}

/* Increments ref count of DH key.
 *
 * @param [in, out] dh  DH key.
 * @return  1 on success
 * @return  0 on error
 */
int wolfSSL_DH_up_ref(WOLFSSL_DH* dh)
{
    int err = 1;

    WOLFSSL_ENTER("wolfSSL_DH_up_ref");

    if (dh != NULL) {
        wolfSSL_RefInc(&dh->ref, &err);
    }

    return !err;
}

#if defined(WOLFSSL_QT) || defined(OPENSSL_ALL) || defined(WOLFSSL_OPENSSH) || \
    defined(OPENSSL_EXTRA)

#ifdef WOLFSSL_DH_EXTRA
/* Duplicate the DH key.
 *
 * Internal DH key in 'dh' is updated if necessary.
 *
 * @param [in, out] dh  DH key to duplicate.
 * @return  NULL on failure.
 * @return  DH key on success.
 */
WOLFSSL_DH* wolfSSL_DH_dup(WOLFSSL_DH* dh)
{
    WOLFSSL_DH* ret = NULL;
    int err = 0;

    WOLFSSL_ENTER("wolfSSL_DH_dup");

    /* Validate parameters. */
    if (dh == NULL) {
        WOLFSSL_ERROR_MSG("Bad parameter");
        err = 1;
    }

    /* Ensure internal DH key is set. */
    if ((!err) && (dh->inSet == 0) && (SetDhInternal(dh) != 1)) {
        WOLFSSL_ERROR_MSG("Bad DH set internal");
        err = 1;
    }

    /* Create a new DH key object. */
    if ((!err) && (!(ret = wolfSSL_DH_new()))) {
        WOLFSSL_ERROR_MSG("wolfSSL_DH_new error");
        err = 1;
    }
    /* Copy internal DH key from original to new. */
    if ((!err) && (wc_DhKeyCopy((DhKey*)dh->internal, (DhKey*)ret->internal) !=
            MP_OKAY)) {
        WOLFSSL_ERROR_MSG("wc_DhKeyCopy error");
        err = 1;
    }
    if (!err) {
        ret->inSet = 1;

         /* Synchronize the internal into external DH key's parameters. */
        if (SetDhExternal(ret) != 1) {
            WOLFSSL_ERROR_MSG("SetDhExternal error");
            err = 1;
        }
    }

    /* Dispose of any allocated DH key on error. */
    if (err && (ret != NULL)) {
        wolfSSL_DH_free(ret);
        ret = NULL;
    }
    return ret;
}
#endif /* WOLFSSL_DH_EXTRA */

#endif

/* Allocate and initialize a new DH key with 2048-bit parameters.
 *
 * See RFC 5114 section 2.3, "2048-bit MODP Group with 256-bit Prime Order
 * Subgroup."
 *
 * @return  NULL on failure.
 * @return  DH Key on success.
 */
WOLFSSL_DH* wolfSSL_DH_get_2048_256(void)
{
    WOLFSSL_DH* dh;
    int err = 0;
    static const byte pHex[] = {
        0x87, 0xA8, 0xE6, 0x1D, 0xB4, 0xB6, 0x66, 0x3C, 0xFF, 0xBB, 0xD1, 0x9C,
        0x65, 0x19, 0x59, 0x99, 0x8C, 0xEE, 0xF6, 0x08, 0x66, 0x0D, 0xD0, 0xF2,
        0x5D, 0x2C, 0xEE, 0xD4, 0x43, 0x5E, 0x3B, 0x00, 0xE0, 0x0D, 0xF8, 0xF1,
        0xD6, 0x19, 0x57, 0xD4, 0xFA, 0xF7, 0xDF, 0x45, 0x61, 0xB2, 0xAA, 0x30,
        0x16, 0xC3, 0xD9, 0x11, 0x34, 0x09, 0x6F, 0xAA, 0x3B, 0xF4, 0x29, 0x6D,
        0x83, 0x0E, 0x9A, 0x7C, 0x20, 0x9E, 0x0C, 0x64, 0x97, 0x51, 0x7A, 0xBD,
        0x5A, 0x8A, 0x9D, 0x30, 0x6B, 0xCF, 0x67, 0xED, 0x91, 0xF9, 0xE6, 0x72,
        0x5B, 0x47, 0x58, 0xC0, 0x22, 0xE0, 0xB1, 0xEF, 0x42, 0x75, 0xBF, 0x7B,
        0x6C, 0x5B, 0xFC, 0x11, 0xD4, 0x5F, 0x90, 0x88, 0xB9, 0x41, 0xF5, 0x4E,
        0xB1, 0xE5, 0x9B, 0xB8, 0xBC, 0x39, 0xA0, 0xBF, 0x12, 0x30, 0x7F, 0x5C,
        0x4F, 0xDB, 0x70, 0xC5, 0x81, 0xB2, 0x3F, 0x76, 0xB6, 0x3A, 0xCA, 0xE1,
        0xCA, 0xA6, 0xB7, 0x90, 0x2D, 0x52, 0x52, 0x67, 0x35, 0x48, 0x8A, 0x0E,
        0xF1, 0x3C, 0x6D, 0x9A, 0x51, 0xBF, 0xA4, 0xAB, 0x3A, 0xD8, 0x34, 0x77,
        0x96, 0x52, 0x4D, 0x8E, 0xF6, 0xA1, 0x67, 0xB5, 0xA4, 0x18, 0x25, 0xD9,
        0x67, 0xE1, 0x44, 0xE5, 0x14, 0x05, 0x64, 0x25, 0x1C, 0xCA, 0xCB, 0x83,
        0xE6, 0xB4, 0x86, 0xF6, 0xB3, 0xCA, 0x3F, 0x79, 0x71, 0x50, 0x60, 0x26,
        0xC0, 0xB8, 0x57, 0xF6, 0x89, 0x96, 0x28, 0x56, 0xDE, 0xD4, 0x01, 0x0A,
        0xBD, 0x0B, 0xE6, 0x21, 0xC3, 0xA3, 0x96, 0x0A, 0x54, 0xE7, 0x10, 0xC3,
        0x75, 0xF2, 0x63, 0x75, 0xD7, 0x01, 0x41, 0x03, 0xA4, 0xB5, 0x43, 0x30,
        0xC1, 0x98, 0xAF, 0x12, 0x61, 0x16, 0xD2, 0x27, 0x6E, 0x11, 0x71, 0x5F,
        0x69, 0x38, 0x77, 0xFA, 0xD7, 0xEF, 0x09, 0xCA, 0xDB, 0x09, 0x4A, 0xE9,
        0x1E, 0x1A, 0x15, 0x97
    };
    static const byte gHex[] = {
        0x3F, 0xB3, 0x2C, 0x9B, 0x73, 0x13, 0x4D, 0x0B, 0x2E, 0x77, 0x50, 0x66,
        0x60, 0xED, 0xBD, 0x48, 0x4C, 0xA7, 0xB1, 0x8F, 0x21, 0xEF, 0x20, 0x54,
        0x07, 0xF4, 0x79, 0x3A, 0x1A, 0x0B, 0xA1, 0x25, 0x10, 0xDB, 0xC1, 0x50,
        0x77, 0xBE, 0x46, 0x3F, 0xFF, 0x4F, 0xED, 0x4A, 0xAC, 0x0B, 0xB5, 0x55,
        0xBE, 0x3A, 0x6C, 0x1B, 0x0C, 0x6B, 0x47, 0xB1, 0xBC, 0x37, 0x73, 0xBF,
        0x7E, 0x8C, 0x6F, 0x62, 0x90, 0x12, 0x28, 0xF8, 0xC2, 0x8C, 0xBB, 0x18,
        0xA5, 0x5A, 0xE3, 0x13, 0x41, 0x00, 0x0A, 0x65, 0x01, 0x96, 0xF9, 0x31,
        0xC7, 0x7A, 0x57, 0xF2, 0xDD, 0xF4, 0x63, 0xE5, 0xE9, 0xEC, 0x14, 0x4B,
        0x77, 0x7D, 0xE6, 0x2A, 0xAA, 0xB8, 0xA8, 0x62, 0x8A, 0xC3, 0x76, 0xD2,
        0x82, 0xD6, 0xED, 0x38, 0x64, 0xE6, 0x79, 0x82, 0x42, 0x8E, 0xBC, 0x83,
        0x1D, 0x14, 0x34, 0x8F, 0x6F, 0x2F, 0x91, 0x93, 0xB5, 0x04, 0x5A, 0xF2,
        0x76, 0x71, 0x64, 0xE1, 0xDF, 0xC9, 0x67, 0xC1, 0xFB, 0x3F, 0x2E, 0x55,
        0xA4, 0xBD, 0x1B, 0xFF, 0xE8, 0x3B, 0x9C, 0x80, 0xD0, 0x52, 0xB9, 0x85,
        0xD1, 0x82, 0xEA, 0x0A, 0xDB, 0x2A, 0x3B, 0x73, 0x13, 0xD3, 0xFE, 0x14,
        0xC8, 0x48, 0x4B, 0x1E, 0x05, 0x25, 0x88, 0xB9, 0xB7, 0xD2, 0xBB, 0xD2,
        0xDF, 0x01, 0x61, 0x99, 0xEC, 0xD0, 0x6E, 0x15, 0x57, 0xCD, 0x09, 0x15,
        0xB3, 0x35, 0x3B, 0xBB, 0x64, 0xE0, 0xEC, 0x37, 0x7F, 0xD0, 0x28, 0x37,
        0x0D, 0xF9, 0x2B, 0x52, 0xC7, 0x89, 0x14, 0x28, 0xCD, 0xC6, 0x7E, 0xB6,
        0x18, 0x4B, 0x52, 0x3D, 0x1D, 0xB2, 0x46, 0xC3, 0x2F, 0x63, 0x07, 0x84,
        0x90, 0xF0, 0x0E, 0xF8, 0xD6, 0x47, 0xD1, 0x48, 0xD4, 0x79, 0x54, 0x51,
        0x5E, 0x23, 0x27, 0xCF, 0xEF, 0x98, 0xC5, 0x82, 0x66, 0x4B, 0x4C, 0x0F,
        0x6C, 0xC4, 0x16, 0x59
    };
    static const byte qHex[] = {
        0x8C, 0xF8, 0x36, 0x42, 0xA7, 0x09, 0xA0, 0x97, 0xB4, 0x47, 0x99, 0x76,
        0x40, 0x12, 0x9D, 0xA2, 0x99, 0xB1, 0xA4, 0x7D, 0x1E, 0xB3, 0x75, 0x0B,
        0xA3, 0x08, 0xB0, 0xFE, 0x64, 0xF5, 0xFB, 0xD3
    };

    /* Create a new DH key to return. */
    dh = wolfSSL_DH_new();
    if (dh == NULL) {
        err = 1;
    }
    if (!err) {
        /* Set prime. */
        dh->p = wolfSSL_BN_bin2bn(pHex, (int)sizeof(pHex), NULL);
        if (dh->p == NULL) {
            WOLFSSL_ERROR_MSG("Error converting p hex to WOLFSSL_BIGNUM.");
            err = 1;
        }
    }
    if (!err) {
        /* Set generator. */
        dh->g = wolfSSL_BN_bin2bn(gHex, (int)sizeof(gHex), NULL);
        if (dh->g == NULL) {
            WOLFSSL_ERROR_MSG("Error converting g hex to WOLFSSL_BIGNUM.");
            err = 1;
        }
    }
    if (!err) {
        /* Set order. */
        dh->q = wolfSSL_BN_bin2bn(qHex, (int)sizeof(qHex), NULL);
        if (dh->q == NULL) {
            WOLFSSL_ERROR_MSG("Error converting q hex to WOLFSSL_BIGNUM.");
            err = 1;
        }
    }
    /* Set values into wolfSSL DH key. */
    if ((!err) && (SetDhInternal(dh) != 1)) {
        WOLFSSL_ERROR_MSG("Error setting DH parameters.");
        err = 1;
    }
    if (!err) {
        /* External DH key parameters were set. */
        dh->exSet = 1;
    }

    /* Dispose of any allocated DH key on error. */
    if (err && (dh != NULL)) {
        wolfSSL_DH_free(dh);
        dh = NULL;
    }

    return dh;
}

/* TODO: consider changing strings to byte arrays. */

/* Returns a big number with the 768-bit prime from RFC 2409.
 *
 * @param [in, out] bn  If not NULL then this BN is set and returned.
 *                      If NULL then a new BN is created, set and returned.
 *
 * @return  NULL on failure.
 * @return  WOLFSSL_BIGNUM with value set to 768-bit prime on success.
 */
WOLFSSL_BIGNUM* wolfSSL_DH_768_prime(WOLFSSL_BIGNUM* bn)
{
#if WOLFSSL_MAX_BN_BITS >= 768
    static const char prm[] = {
        "FFFFFFFFFFFFFFFFC90FDAA22168C234"
        "C4C6628B80DC1CD129024E088A67CC74"
        "020BBEA63B139B22514A08798E3404DD"
        "EF9519B3CD3A431B302B0A6DF25F1437"
        "4FE1356D6D51C245E485B576625E7EC6"
        "F44C42E9A63A3620FFFFFFFFFFFFFFFF"
    };

    WOLFSSL_ENTER("wolfSSL_DH_768_prime");

    /* Set prime into BN. Creates a new BN when bn is NULL. */
    if (wolfSSL_BN_hex2bn(&bn, prm) != 1) {
        WOLFSSL_ERROR_MSG("Error converting DH 768 prime to big number");
        bn = NULL;
    }

    return bn;
#else
    (void)bn;
    return NULL;
#endif
}

/* Returns a big number with the 1024-bit prime from RFC 2409.
 *
 * @param [in, out] bn  If not NULL then this BN is set and returned.
 *                      If NULL then a new BN is created, set and returned.
 *
 * @return  NULL on failure.
 * @return  WOLFSSL_BIGNUM with value set to 1024-bit prime on success.
 */
WOLFSSL_BIGNUM* wolfSSL_DH_1024_prime(WOLFSSL_BIGNUM* bn)
{
#if WOLFSSL_MAX_BN_BITS >= 1024
    static const char prm[] = {
        "FFFFFFFFFFFFFFFFC90FDAA22168C234"
        "C4C6628B80DC1CD129024E088A67CC74"
        "020BBEA63B139B22514A08798E3404DD"
        "EF9519B3CD3A431B302B0A6DF25F1437"
        "4FE1356D6D51C245E485B576625E7EC6"
        "F44C42E9A637ED6B0BFF5CB6F406B7ED"
        "EE386BFB5A899FA5AE9F24117C4B1FE6"
        "49286651ECE65381FFFFFFFFFFFFFFFF"
    };

    WOLFSSL_ENTER("wolfSSL_DH_1024_prime");

    /* Set prime into BN. Creates a new BN when bn is NULL. */
    if (wolfSSL_BN_hex2bn(&bn, prm) != 1) {
        WOLFSSL_ERROR_MSG("Error converting DH 1024 prime to big number");
        bn = NULL;
    }

    return bn;
#else
    (void)bn;
    return NULL;
#endif
}

/* Returns a big number with the 1536-bit prime from RFC 3526.
 *
 * @param [in, out] bn  If not NULL then this BN is set and returned.
 *                      If NULL then a new BN is created, set and returned.
 *
 * @return  NULL on failure.
 * @return  WOLFSSL_BIGNUM with value set to 1536-bit prime on success.
 */
WOLFSSL_BIGNUM* wolfSSL_DH_1536_prime(WOLFSSL_BIGNUM* bn)
{
#if WOLFSSL_MAX_BN_BITS >= 1536
    static const char prm[] = {
        "FFFFFFFFFFFFFFFFC90FDAA22168C234"
        "C4C6628B80DC1CD129024E088A67CC74"
        "020BBEA63B139B22514A08798E3404DD"
        "EF9519B3CD3A431B302B0A6DF25F1437"
        "4FE1356D6D51C245E485B576625E7EC6"
        "F44C42E9A637ED6B0BFF5CB6F406B7ED"
        "EE386BFB5A899FA5AE9F24117C4B1FE6"
        "49286651ECE45B3DC2007CB8A163BF05"
        "98DA48361C55D39A69163FA8FD24CF5F"
        "83655D23DCA3AD961C62F356208552BB"
        "9ED529077096966D670C354E4ABC9804"
        "F1746C08CA237327FFFFFFFFFFFFFFFF"
    };

    WOLFSSL_ENTER("wolfSSL_DH_1536_prime");

    /* Set prime into BN. Creates a new BN when bn is NULL. */
    if (wolfSSL_BN_hex2bn(&bn, prm) != 1) {
        WOLFSSL_ERROR_MSG("Error converting DH 1536 prime to big number");
        bn = NULL;
    }

    return bn;
#else
    (void)bn;
    return NULL;
#endif
}

/* Returns a big number with the 2048-bit prime from RFC 3526.
 *
 * @param [in, out] bn  If not NULL then this BN is set and returned.
 *                      If NULL then a new BN is created, set and returned.
 *
 * @return  NULL on failure.
 * @return  WOLFSSL_BIGNUM with value set to 2048-bit prime on success.
 */
WOLFSSL_BIGNUM* wolfSSL_DH_2048_prime(WOLFSSL_BIGNUM* bn)
{
#if WOLFSSL_MAX_BN_BITS >= 2048
    static const char prm[] = {
        "FFFFFFFFFFFFFFFFC90FDAA22168C234"
        "C4C6628B80DC1CD129024E088A67CC74"
        "020BBEA63B139B22514A08798E3404DD"
        "EF9519B3CD3A431B302B0A6DF25F1437"
        "4FE1356D6D51C245E485B576625E7EC6"
        "F44C42E9A637ED6B0BFF5CB6F406B7ED"
        "EE386BFB5A899FA5AE9F24117C4B1FE6"
        "49286651ECE45B3DC2007CB8A163BF05"
        "98DA48361C55D39A69163FA8FD24CF5F"
        "83655D23DCA3AD961C62F356208552BB"
        "9ED529077096966D670C354E4ABC9804"
        "F1746C08CA18217C32905E462E36CE3B"
        "E39E772C180E86039B2783A2EC07A28F"
        "B5C55DF06F4C52C9DE2BCBF695581718"
        "3995497CEA956AE515D2261898FA0510"
        "15728E5A8AACAA68FFFFFFFFFFFFFFFF"
    };

    WOLFSSL_ENTER("wolfSSL_DH_2048_prime");

    /* Set prime into BN. Creates a new BN when bn is NULL. */
    if (wolfSSL_BN_hex2bn(&bn, prm) != 1) {
        WOLFSSL_ERROR_MSG("Error converting DH 2048 prime to big number");
        bn = NULL;
    }

    return bn;
#else
    (void)bn;
    return NULL;
#endif
}

/* Returns a big number with the 3072-bit prime from RFC 3526.
 *
 * @param [in, out] bn  If not NULL then this BN is set and returned.
 *                      If NULL then a new BN is created, set and returned.
 *
 * @return  NULL on failure.
 * @return  WOLFSSL_BIGNUM with value set to 3072-bit prime on success.
 */
WOLFSSL_BIGNUM* wolfSSL_DH_3072_prime(WOLFSSL_BIGNUM* bn)
{
#if WOLFSSL_MAX_BN_BITS >= 3072
    static const char prm[] = {
        "FFFFFFFFFFFFFFFFC90FDAA22168C234"
        "C4C6628B80DC1CD129024E088A67CC74"
        "020BBEA63B139B22514A08798E3404DD"
        "EF9519B3CD3A431B302B0A6DF25F1437"
        "4FE1356D6D51C245E485B576625E7EC6"
        "F44C42E9A637ED6B0BFF5CB6F406B7ED"
        "EE386BFB5A899FA5AE9F24117C4B1FE6"
        "49286651ECE45B3DC2007CB8A163BF05"
        "98DA48361C55D39A69163FA8FD24CF5F"
        "83655D23DCA3AD961C62F356208552BB"
        "9ED529077096966D670C354E4ABC9804"
        "F1746C08CA18217C32905E462E36CE3B"
        "E39E772C180E86039B2783A2EC07A28F"
        "B5C55DF06F4C52C9DE2BCBF695581718"
        "3995497CEA956AE515D2261898FA0510"
        "15728E5A8AAAC42DAD33170D04507A33"
        "A85521ABDF1CBA64ECFB850458DBEF0A"
        "8AEA71575D060C7DB3970F85A6E1E4C7"
        "ABF5AE8CDB0933D71E8C94E04A25619D"
        "CEE3D2261AD2EE6BF12FFA06D98A0864"
        "D87602733EC86A64521F2B18177B200C"
        "BBE117577A615D6C770988C0BAD946E2"
        "08E24FA074E5AB3143DB5BFCE0FD108E"
        "4B82D120A93AD2CAFFFFFFFFFFFFFFFF"
    };

    WOLFSSL_ENTER("wolfSSL_DH_3072_prime");

    /* Set prime into BN. Creates a new BN when bn is NULL. */
    if (wolfSSL_BN_hex2bn(&bn, prm) != 1) {
        WOLFSSL_ERROR_MSG("Error converting DH 3072 prime to big number");
        bn = NULL;
    }

    return bn;
#else
    (void)bn;
    return NULL;
#endif
}

/* Returns a big number with the 4096-bit prime from RFC 3526.
 *
 * @param [in, out] bn  If not NULL then this BN is set and returned.
 *                      If NULL then a new BN is created, set and returned.
 *
 * @return  NULL on failure.
 * @return  WOLFSSL_BIGNUM with value set to 4096-bit prime on success.
 */
WOLFSSL_BIGNUM* wolfSSL_DH_4096_prime(WOLFSSL_BIGNUM* bn)
{
#if WOLFSSL_MAX_BN_BITS >= 4096
    static const char prm[] = {
        "FFFFFFFFFFFFFFFFC90FDAA22168C234"
        "C4C6628B80DC1CD129024E088A67CC74"
        "020BBEA63B139B22514A08798E3404DD"
        "EF9519B3CD3A431B302B0A6DF25F1437"
        "4FE1356D6D51C245E485B576625E7EC6"
        "F44C42E9A637ED6B0BFF5CB6F406B7ED"
        "EE386BFB5A899FA5AE9F24117C4B1FE6"
        "49286651ECE45B3DC2007CB8A163BF05"
        "98DA48361C55D39A69163FA8FD24CF5F"
        "83655D23DCA3AD961C62F356208552BB"
        "9ED529077096966D670C354E4ABC9804"
        "F1746C08CA18217C32905E462E36CE3B"
        "E39E772C180E86039B2783A2EC07A28F"
        "B5C55DF06F4C52C9DE2BCBF695581718"
        "3995497CEA956AE515D2261898FA0510"
        "15728E5A8AAAC42DAD33170D04507A33"
        "A85521ABDF1CBA64ECFB850458DBEF0A"
        "8AEA71575D060C7DB3970F85A6E1E4C7"
        "ABF5AE8CDB0933D71E8C94E04A25619D"
        "CEE3D2261AD2EE6BF12FFA06D98A0864"
        "D87602733EC86A64521F2B18177B200C"
        "BBE117577A615D6C770988C0BAD946E2"
        "08E24FA074E5AB3143DB5BFCE0FD108E"
        "4B82D120A92108011A723C12A787E6D7"
        "88719A10BDBA5B2699C327186AF4E23C"
        "1A946834B6150BDA2583E9CA2AD44CE8"
        "DBBBC2DB04DE8EF92E8EFC141FBECAA6"
        "287C59474E6BC05D99B2964FA090C3A2"
        "233BA186515BE7ED1F612970CEE2D7AF"
        "B81BDD762170481CD0069127D5B05AA9"
        "93B4EA988D8FDDC186FFB7DC90A6C08F"
        "4DF435C934063199FFFFFFFFFFFFFFFF"
    };

    WOLFSSL_ENTER("wolfSSL_DH_4096_prime");

    /* Set prime into BN. Creates a new BN when bn is NULL. */
    if (wolfSSL_BN_hex2bn(&bn, prm) != 1) {
        WOLFSSL_ERROR_MSG("Error converting DH 4096 prime to big number");
        bn = NULL;
    }

    return bn;
#else
    (void)bn;
    return NULL;
#endif
}

/* Returns a big number with the 6144-bit prime from RFC 3526.
 *
 * @param [in, out] bn  If not NULL then this BN is set and returned.
 *                      If NULL then a new BN is created, set and returned.
 *
 * @return  NULL on failure.
 * @return  WOLFSSL_BIGNUM with value set to 6144-bit prime on success.
 */
WOLFSSL_BIGNUM* wolfSSL_DH_6144_prime(WOLFSSL_BIGNUM* bn)
{
#if WOLFSSL_MAX_BN_BITS >= 6144
    static const char prm[] = {
        "FFFFFFFFFFFFFFFFC90FDAA22168C234"
        "C4C6628B80DC1CD129024E088A67CC74"
        "020BBEA63B139B22514A08798E3404DD"
        "EF9519B3CD3A431B302B0A6DF25F1437"
        "4FE1356D6D51C245E485B576625E7EC6"
        "F44C42E9A637ED6B0BFF5CB6F406B7ED"
        "EE386BFB5A899FA5AE9F24117C4B1FE6"
        "49286651ECE45B3DC2007CB8A163BF05"
        "98DA48361C55D39A69163FA8FD24CF5F"
        "83655D23DCA3AD961C62F356208552BB"
        "9ED529077096966D670C354E4ABC9804"
        "F1746C08CA18217C32905E462E36CE3B"
        "E39E772C180E86039B2783A2EC07A28F"
        "B5C55DF06F4C52C9DE2BCBF695581718"
        "3995497CEA956AE515D2261898FA0510"
        "15728E5A8AAAC42DAD33170D04507A33"
        "A85521ABDF1CBA64ECFB850458DBEF0A"
        "8AEA71575D060C7DB3970F85A6E1E4C7"
        "ABF5AE8CDB0933D71E8C94E04A25619D"
        "CEE3D2261AD2EE6BF12FFA06D98A0864"
        "D87602733EC86A64521F2B18177B200C"
        "BBE117577A615D6C770988C0BAD946E2"
        "08E24FA074E5AB3143DB5BFCE0FD108E"
        "4B82D120A92108011A723C12A787E6D7"
        "88719A10BDBA5B2699C327186AF4E23C"
        "1A946834B6150BDA2583E9CA2AD44CE8"
        "DBBBC2DB04DE8EF92E8EFC141FBECAA6"
        "287C59474E6BC05D99B2964FA090C3A2"
        "233BA186515BE7ED1F612970CEE2D7AF"
        "B81BDD762170481CD0069127D5B05AA9"
        "93B4EA988D8FDDC186FFB7DC90A6C08F"
        "4DF435C93402849236C3FAB4D27C7026"
        "C1D4DCB2602646DEC9751E763DBA37BD"
        "F8FF9406AD9E530EE5DB382F413001AE"
        "B06A53ED9027D831179727B0865A8918"
        "DA3EDBEBCF9B14ED44CE6CBACED4BB1B"
        "DB7F1447E6CC254B332051512BD7AF42"
        "6FB8F401378CD2BF5983CA01C64B92EC"
        "F032EA15D1721D03F482D7CE6E74FEF6"
        "D55E702F46980C82B5A84031900B1C9E"
        "59E7C97FBEC7E8F323A97A7E36CC88BE"
        "0F1D45B7FF585AC54BD407B22B4154AA"
        "CC8F6D7EBF48E1D814CC5ED20F8037E0"
        "A79715EEF29BE32806A1D58BB7C5DA76"
        "F550AA3D8A1FBFF0EB19CCB1A313D55C"
        "DA56C9EC2EF29632387FE8D76E3C0468"
        "043E8F663F4860EE12BF2D5B0B7474D6"
        "E694F91E6DCC4024FFFFFFFFFFFFFFFF"
    };

    WOLFSSL_ENTER("wolfSSL_DH_6144_prime");

    /* Set prime into BN. Creates a new BN when bn is NULL. */
    if (wolfSSL_BN_hex2bn(&bn, prm) != 1) {
        WOLFSSL_ERROR_MSG("Error converting DH 6144 prime to big number");
        bn = NULL;
    }

    return bn;
#else
    (void)bn;
    return NULL;
#endif
}


/* Returns a big number with the 8192-bit prime from RFC 3526.
 *
 * @param [in, out] bn  If not NULL then this BN is set and returned.
 *                      If NULL then a new BN is created, set and returned.
 *
 * @return  NULL on failure.
 * @return  WOLFSSL_BIGNUM with value set to 8192-bit prime on success.
 */
WOLFSSL_BIGNUM* wolfSSL_DH_8192_prime(WOLFSSL_BIGNUM* bn)
{
#if WOLFSSL_MAX_BN_BITS >= 8192
    static const char prm[] = {
        "FFFFFFFFFFFFFFFFC90FDAA22168C234"
        "C4C6628B80DC1CD129024E088A67CC74"
        "020BBEA63B139B22514A08798E3404DD"
        "EF9519B3CD3A431B302B0A6DF25F1437"
        "4FE1356D6D51C245E485B576625E7EC6"
        "F44C42E9A637ED6B0BFF5CB6F406B7ED"
        "EE386BFB5A899FA5AE9F24117C4B1FE6"
        "49286651ECE45B3DC2007CB8A163BF05"
        "98DA48361C55D39A69163FA8FD24CF5F"
        "83655D23DCA3AD961C62F356208552BB"
        "9ED529077096966D670C354E4ABC9804"
        "F1746C08CA18217C32905E462E36CE3B"
        "E39E772C180E86039B2783A2EC07A28F"
        "B5C55DF06F4C52C9DE2BCBF695581718"
        "3995497CEA956AE515D2261898FA0510"
        "15728E5A8AAAC42DAD33170D04507A33"
        "A85521ABDF1CBA64ECFB850458DBEF0A"
        "8AEA71575D060C7DB3970F85A6E1E4C7"
        "ABF5AE8CDB0933D71E8C94E04A25619D"
        "CEE3D2261AD2EE6BF12FFA06D98A0864"
        "D87602733EC86A64521F2B18177B200C"
        "BBE117577A615D6C770988C0BAD946E2"
        "08E24FA074E5AB3143DB5BFCE0FD108E"
        "4B82D120A92108011A723C12A787E6D7"
        "88719A10BDBA5B2699C327186AF4E23C"
        "1A946834B6150BDA2583E9CA2AD44CE8"
        "DBBBC2DB04DE8EF92E8EFC141FBECAA6"
        "287C59474E6BC05D99B2964FA090C3A2"
        "233BA186515BE7ED1F612970CEE2D7AF"
        "B81BDD762170481CD0069127D5B05AA9"
        "93B4EA988D8FDDC186FFB7DC90A6C08F"
        "4DF435C93402849236C3FAB4D27C7026"
        "C1D4DCB2602646DEC9751E763DBA37BD"
        "F8FF9406AD9E530EE5DB382F413001AE"
        "B06A53ED9027D831179727B0865A8918"
        "DA3EDBEBCF9B14ED44CE6CBACED4BB1B"
        "DB7F1447E6CC254B332051512BD7AF42"
        "6FB8F401378CD2BF5983CA01C64B92EC"
        "F032EA15D1721D03F482D7CE6E74FEF6"
        "D55E702F46980C82B5A84031900B1C9E"
        "59E7C97FBEC7E8F323A97A7E36CC88BE"
        "0F1D45B7FF585AC54BD407B22B4154AA"
        "CC8F6D7EBF48E1D814CC5ED20F8037E0"
        "A79715EEF29BE32806A1D58BB7C5DA76"
        "F550AA3D8A1FBFF0EB19CCB1A313D55C"
        "DA56C9EC2EF29632387FE8D76E3C0468"
        "043E8F663F4860EE12BF2D5B0B7474D6"
        "E694F91E6DBE115974A3926F12FEE5E4"
        "38777CB6A932DF8CD8BEC4D073B931BA"
        "3BC832B68D9DD300741FA7BF8AFC47ED"
        "2576F6936BA424663AAB639C5AE4F568"
        "3423B4742BF1C978238F16CBE39D652D"
        "E3FDB8BEFC848AD922222E04A4037C07"
        "13EB57A81A23F0C73473FC646CEA306B"
        "4BCBC8862F8385DDFA9D4B7FA2C087E8"
        "79683303ED5BDD3A062B3CF5B3A278A6"
        "6D2A13F83F44F82DDF310EE074AB6A36"
        "4597E899A0255DC164F31CC50846851D"
        "F9AB48195DED7EA1B1D510BD7EE74D73"
        "FAF36BC31ECFA268359046F4EB879F92"
        "4009438B481C6CD7889A002ED5EE382B"
        "C9190DA6FC026E479558E4475677E9AA"
        "9E3050E2765694DFC81F56E880B96E71"
        "60C980DD98EDD3DFFFFFFFFFFFFFFFFF"
    };

    WOLFSSL_ENTER("wolfSSL_DH_8192_prime");

    /* Set prime into BN. Creates a new BN when bn is NULL. */
    if (wolfSSL_BN_hex2bn(&bn, prm) != 1) {
        WOLFSSL_ERROR_MSG("Error converting DH 8192 prime to big number");
        bn = NULL;
    }

    return bn;
#else
    (void)bn;
    return NULL;
#endif
}

/*
 * DH to/from bin APIs
 */

#ifndef NO_CERTS

/* Load the DER encoded DH parameters/key into DH key.
 *
 * @param [in, out] dh      DH key to load parameters into.
 * @param [in]      der     Buffer holding DER encoded parameters data.
 * @param [in, out] idx     On in, index at which DH key DER data starts.
 *                          On out, index after DH key DER data.
 * @param [in]      derSz   Size of DER buffer in bytes.
 *
 * @return  0 on success.
 * @return  1 when decoding DER or setting the external key fails.
 */
static int wolfssl_dh_load_key(WOLFSSL_DH* dh, const unsigned char* der,
    word32* idx, word32 derSz)
{
    int err = 0;

#if !defined(HAVE_FIPS) || FIPS_VERSION_GT(2,0)
    int ret;

    /* Decode DH parameters/key from DER. */
    ret = wc_DhKeyDecode(der, idx, (DhKey*)dh->internal, derSz);
    if (ret != 0) {
        WOLFSSL_ERROR_MSG("DhKeyDecode() failed");
        err = 1;
    }
    if (!err) {
        /* wolfSSL DH key set. */
        dh->inSet = 1;

        /* Set the external DH key based on wolfSSL DH key. */
        if (SetDhExternal(dh) != 1) {
            WOLFSSL_ERROR_MSG("SetDhExternal failed");
            err = 1;
        }
    }
#else
    byte* p;
    byte* g;
    word32 pSz = MAX_DH_SIZE;
    word32 gSz = MAX_DH_SIZE;

    /* Only DH parameters supported. */
    /* Load external and set internal. */
    p = (byte*)XMALLOC(pSz, NULL, DYNAMIC_TYPE_PUBLIC_KEY);
    g = (byte*)XMALLOC(gSz, NULL, DYNAMIC_TYPE_PUBLIC_KEY);
    if ((p == NULL) || (g == NULL)) {
        err = 1;
    }
    /* Extract the p and g as data from the DER encoded DH parameters. */
    if ((!err) && (wc_DhParamsLoad(der + *idx, derSz - *idx, p, &pSz, g,
            &gSz) < 0)) {
        err = 1;
    }
    if (!err) {
        /* Put p and g in as big numbers - free existing BNs. */
        if (dh->p != NULL) {
            wolfSSL_BN_free(dh->p);
            dh->p = NULL;
        }
        if (dh->g != NULL) {
            wolfSSL_BN_free(dh->g);
            dh->g = NULL;
        }
        dh->p = wolfSSL_BN_bin2bn(p, (int)pSz, NULL);
        dh->g = wolfSSL_BN_bin2bn(g, (int)gSz, NULL);
        if (dh->p == NULL || dh->g == NULL) {
            err = 1;
        }
        else {
            /* External DH key parameters were set. */
            dh->exSet = 1;
        }
    }

    /* Set internal as the outside has been updated. */
    if ((!err) && (SetDhInternal(dh) != 1)) {
        WOLFSSL_ERROR_MSG("Unable to set internal DH structure");
        err = 1;
    }

    if (!err) {
        *idx += wolfssl_der_length(der + *idx, derSz - *idx);
    }

    XFREE(p, NULL, DYNAMIC_TYPE_PUBLIC_KEY);
    XFREE(g, NULL, DYNAMIC_TYPE_PUBLIC_KEY);
#endif

    return err;
}

#ifdef OPENSSL_ALL

#if !defined(HAVE_FIPS) || FIPS_VERSION_GT(2,0)
/* Convert DER encoded DH parameters to a WOLFSSL_DH structure.
 *
 * @param [out]     dh      DH key to put parameters into. May be NULL.
 * @param [in, out] pp      Pointer to DER encoded DH parameters.
 *                          Value updated to end of data when dh is not NULL.
 * @param [in]      length  Length of data available in bytes.
 *
 * @return  DH key on success.
 * @return  NULL on failure.
 */
WOLFSSL_DH *wolfSSL_d2i_DHparams(WOLFSSL_DH** dh, const unsigned char** pp,
    long length)
{
    WOLFSSL_DH *newDh = NULL;
    word32 idx = 0;
    int err = 0;

    WOLFSSL_ENTER("wolfSSL_d2i_DHparams");

    /* Validate parameters. */
    if ((pp == NULL) || (length <= 0)) {
        WOLFSSL_ERROR_MSG("bad argument");
        err = 1;
    }

    /* Create new DH key to return. */
    if ((!err) && ((newDh = wolfSSL_DH_new()) == NULL)) {
        WOLFSSL_ERROR_MSG("wolfSSL_DH_new() failed");
        err = 1;
    }
    if ((!err) && (wolfssl_dh_load_key(newDh, *pp, &idx,
            (word32)length) != 0)) {
        WOLFSSL_ERROR_MSG("Loading DH parameters failed");
        err = 1;
    }

    if ((!err) && (dh != NULL)) {
        /* Return through parameter too. */
        *dh = newDh;
        /* Move buffer on by the used amount. */
        *pp += idx;
    }

    if (err && (newDh != NULL)) {
        /* Dispose of any created DH key. */
        wolfSSL_DH_free(newDh);
        newDh = NULL;
    }
    return newDh;
}
#endif /* !HAVE_FIPS || FIPS_VERSION_GT(2,0) */

/* Converts internal WOLFSSL_DH structure to DER encoded DH parameters.
 *
 * @params [in]      dh   DH key with parameters to encode.
 * @params [in, out] out  Pointer to buffer to encode into.
 *                        When NULL or pointer to NULL, only length returned.
 * @return  0 on error.
 * @return  Size of DER encoding in bytes on success.
 */
int wolfSSL_i2d_DHparams(const WOLFSSL_DH *dh, unsigned char **out)
{
#if (!defined(HAVE_FIPS) || FIPS_VERSION_GT(5,0)) && defined(WOLFSSL_DH_EXTRA)
    /* Set length to an arbitrarily large value for wc_DhParamsToDer(). */
    word32 len = (word32)-1;
    int err = 0;

    /* Validate parameters. */
    if (dh == NULL) {
        WOLFSSL_ERROR_MSG("Bad parameters");
        err = 1;
    }

    /* Push external DH data into internal DH key if not set. */
    if ((!err) && (!dh->inSet) && (SetDhInternal((WOLFSSL_DH*)dh) != 1)) {
        WOLFSSL_ERROR_MSG("Bad DH set internal");
        err = 1;
    }
    if (!err) {
        int ret;
        unsigned char* der = NULL;

        /* Use *out when available otherwise NULL. */
        if (out != NULL) {
            der = *out;
        }
        /* Get length and/or encode. */
        ret = wc_DhParamsToDer((DhKey*)dh->internal, der, &len);
        /* Length of encoded data is returned on success. */
        if (ret > 0) {
            *out += len;
        }
        /* An error occurred unless only length returned. */
        else if (ret != WC_NO_ERR_TRACE(LENGTH_ONLY_E)) {
            err = 1;
        }
    }

    /* Set return to 0 on error. */
    if (err) {
        len = 0;
    }
    return (int)len;
#else
    word32 len;
    int ret = 0;
    int pSz;
    int gSz;

    WOLFSSL_ENTER("wolfSSL_i2d_DHparams");

    /* Validate parameters. */
    if (dh == NULL) {
        WOLFSSL_ERROR_MSG("Bad parameters");
        len = 0;
    }
    else {
        /* SEQ <len>
         *   INT <len> [0x00] <prime>
         *   INT <len> [0x00] <generator>
         * Integers have 0x00 prepended if the top bit of positive number is
         * set.
         */
        /* Get total length of prime including any prepended zeros. */
        pSz = mp_unsigned_bin_size((mp_int*)dh->p->internal) +
              mp_leading_bit((mp_int*)dh->p->internal);
        /* Get total length of generator including any prepended zeros. */
        gSz = mp_unsigned_bin_size((mp_int*)dh->g->internal) +
              mp_leading_bit((mp_int*)dh->g->internal);
        /* Calculate length of data in sequence. */
        len = 1 + ASN_LEN_SIZE(pSz) + pSz +
              1 + ASN_LEN_SIZE(gSz) + gSz;
        /* Add in the length of the SEQUENCE. */
        len += 1 + ASN_LEN_SIZE(len);

        if ((out != NULL) && (*out != NULL)) {
            /* Encode parameters. */
            ret = StoreDHparams(*out, &len, (mp_int*)dh->p->internal,
                (mp_int*)dh->g->internal);
            if (ret != MP_OKAY) {
                WOLFSSL_ERROR_MSG("StoreDHparams error");
                len = 0;
            }
            else {
                /* Move pointer on if encoded. */
                *out += len;
            }
        }
    }

    return (int)len;
#endif
}

#endif /* OPENSSL_ALL */

#endif /* !NO_CERTS */

#endif /* OPENSSL_EXTRA */

#if defined(OPENSSL_EXTRA) ||  \
 ((!defined(NO_BIO) || !defined(NO_FILESYSTEM)) && \
  defined(HAVE_LIGHTY) || defined(HAVE_STUNNEL) || \
  defined(WOLFSSL_MYSQL_COMPATIBLE))

/* Load the DER encoded DH parameters into DH key.
 *
 * @param [in, out] dh      DH key to load parameters into.
 * @param [in]      derBuf  Buffer holding DER encoded parameters data.
 * @param [in]      derSz   Size of DER data in buffer in bytes.
 *
 * @return  1 on success.
 * @return  -1 when DH or derBuf is NULL,
 *                  internal DH key in DH is NULL,
 *                  derSz is 0 or less,
 *                  error decoding DER data or
 *                  setting external parameter values fails.
 */
int wolfSSL_DH_LoadDer(WOLFSSL_DH* dh, const unsigned char* derBuf, int derSz)
{
    int    ret = 1;
    word32 idx = 0;

    /* Validate parameters. */
    if ((dh == NULL) || (dh->internal == NULL) || (derBuf == NULL) ||
            (derSz <= 0)) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = -1;
    }

    if ((ret == 1) && (wolfssl_dh_load_key(dh, derBuf, &idx,
            (word32)derSz) != 0)) {
        WOLFSSL_ERROR_MSG("DH key decode failed");
        ret = -1;
    }

    return ret;
}

#endif

/*
 * DH PEM APIs
 */

#if defined(HAVE_LIGHTY) || defined(HAVE_STUNNEL) \
    || defined(WOLFSSL_MYSQL_COMPATIBLE) || defined(OPENSSL_EXTRA)

#if !defined(NO_BIO) || !defined(NO_FILESYSTEM)
/* Create a DH key by reading the PEM encoded data from the BIO.
 *
 * @param [in]      bio         BIO object to read from.
 * @param [in, out] dh          DH key to use. May be NULL.
 * @param [in]      pem         PEM data to decode.
 * @param [in]      pemSz       Size of PEM data in bytes.
 * @param [in]      memAlloced  Indicates that pem was allocated and is to be
 *                              freed after use.
 * @return  DH key on success.
 * @return  NULL on failure.
 */
static WOLFSSL_DH *wolfssl_dhparams_read_pem(WOLFSSL_DH **dh,
    unsigned char* pem, int pemSz, int memAlloced)
{
    WOLFSSL_DH* localDh = NULL;
    DerBuffer *der = NULL;
    int err = 0;

    /* Convert PEM to DER assuming DH Parameter format. */
    if ((!err) && (PemToDer(pem, pemSz, DH_PARAM_TYPE, &der, NULL, NULL,
            NULL) < 0)) {
        /* Convert PEM to DER assuming X9.42 DH Parameter format. */
        if (PemToDer(pem, pemSz, X942_PARAM_TYPE, &der, NULL, NULL, NULL)
                != 0) {
            err = 1;
        }
        /* If Success on X9.42 DH format, clear error from failed DH format */
        else {
            unsigned long error;
            CLEAR_ASN_NO_PEM_HEADER_ERROR(error);
        }
    }
    if (memAlloced) {
        /* PEM data no longer needed.  */
        XFREE(pem, NULL, DYNAMIC_TYPE_TMP_BUFFER);
    }

    if (!err) {
        /* Use the DH key passed in or allocate a new one. */
        if (dh != NULL) {
            localDh = *dh;
        }
        if (localDh == NULL) {
            localDh = wolfSSL_DH_new();
            if (localDh == NULL) {
                err = 1;
            }
        }
    }
    /* Load the DER encoded DH parameters from buffer into a DH key. */
    if ((!err) && (wolfSSL_DH_LoadDer(localDh, der->buffer, (int)der->length)
            != 1)) {
        /* Free an allocated DH key. */
        if ((dh == NULL) || (localDh != *dh)) {
            wolfSSL_DH_free(localDh);
        }
        localDh = NULL;
        err = 1;
    }
    /* Return the DH key on success. */
    if ((!err) && (dh != NULL)) {
        *dh = localDh;
    }

    /* Dispose of DER data. */
    if (der != NULL) {
        FreeDer(&der);
    }
    return localDh;
}
#endif /* !NO_BIO || !NO_FILESYSTEM */

#ifndef NO_BIO
/* Create a DH key by reading the PEM encoded data from the BIO.
 *
 * DH parameters are public data and are not expected to be encrypted.
 *
 * @param [in]      bio   BIO object to read from.
 * @param [in, out] dh    DH key to   When pointer to
 *                        NULL, a new DH key is created.
 * @param [in]      cb    Password callback when PEM encrypted. Not used.
 * @param [in]      pass  NUL terminated string for passphrase when PEM
 *                        encrypted. Not used.
 * @return  DH key on success.
 * @return  NULL on failure.
 */
WOLFSSL_DH *wolfSSL_PEM_read_bio_DHparams(WOLFSSL_BIO *bio, WOLFSSL_DH **dh,
    wc_pem_password_cb *cb, void *pass)
{
    WOLFSSL_DH* localDh = NULL;
    int err = 0;
    unsigned char* mem = NULL;
    int size = 0;
    int memAlloced = 0;

    WOLFSSL_ENTER("wolfSSL_PEM_read_bio_DHparams");

    (void)cb;
    (void)pass;

    /* Validate parameters. */
    if (bio == NULL) {
        WOLFSSL_ERROR_MSG("Bad Function Argument bio is NULL");
        err = 1;
    }

    /* Get buffer of data from BIO or read data from the BIO into a new buffer.
     */
    if ((!err) && (wolfssl_read_bio(bio, (char**)&mem, &size, &memAlloced)
            != 0)) {
        err = 1;
    }
    if (!err) {
        /* Create a DH key from the PEM - try two different headers. */
        localDh = wolfssl_dhparams_read_pem(dh, mem, size, memAlloced);
    }

    return localDh;
}

#endif /* !NO_BIO */

#ifndef NO_FILESYSTEM
/* Read DH parameters from a file pointer into DH key.
 *
 * DH parameters are public data and are not expected to be encrypted.
 *
 * @param [in]      fp    File pointer to read DH parameter file from.
 * @param [in, out] dh    DH key with parameters if not NULL. When pointer to
 *                        NULL, a new DH key is created.
 * @param [in]      cb    Password callback when PEM encrypted. Not used.
 * @param [in]      pass  NUL terminated string for passphrase when PEM
 *                        encrypted. Not used.
 *
 * @return  NULL on failure.
 * @return  DH key with parameters set on success.
 */
WOLFSSL_DH* wolfSSL_PEM_read_DHparams(XFILE fp, WOLFSSL_DH** dh,
    wc_pem_password_cb* cb, void* pass)
{
    WOLFSSL_DH* localDh = NULL;
    int err = 0;
    unsigned char* mem = NULL;
    int size = 0;

    (void)cb;
    (void)pass;

    /* Read data from file pointer. */
    if (wolfssl_read_file(fp, (char**)&mem, &size) != 0) {
        err = 1;
    }
    if (!err) {
        localDh = wolfssl_dhparams_read_pem(dh, mem, size, 1);
    }

    return localDh;
}
#endif /* !NO_FILESYSTEM */

#if defined(WOLFSSL_DH_EXTRA) && !defined(NO_FILESYSTEM)
/* Encoded parameter data in DH key as DER.
 *
 * @param [in, out] dh    DH key object to encode.
 * @param [out]     out   Buffer containing DER encoding.
 * @param [in]      heap  Heap hint.
 * @return  <0 on error.
 * @return  Length of DER encoded DH parameters in bytes.
 */
static int wolfssl_dhparams_to_der(WOLFSSL_DH* dh, unsigned char** out,
    void* heap)
{
    int ret = -1;
    int err = 0;
    byte* der = NULL;
    word32 derSz;
    DhKey* key = NULL;

    (void)heap;

    /* Set internal parameters based on external parameters. */
    if ((dh->inSet == 0) && (SetDhInternal(dh) != 1)) {
        WOLFSSL_ERROR_MSG("Unable to set internal DH structure");
        err = 1;
    }
    if (!err) {
        /* Use wolfSSL API to get length of DER encode DH parameters. */
        key = (DhKey*)dh->internal;
        ret = wc_DhParamsToDer(key, NULL, &derSz);
        if (ret != WC_NO_ERR_TRACE(LENGTH_ONLY_E)) {
            WOLFSSL_ERROR_MSG("Failed to get size of DH params");
            err = 1;
        }
    }

    if (!err) {
        /* Allocate memory for DER encoding. */
        der = (byte*)XMALLOC(derSz, heap, DYNAMIC_TYPE_TMP_BUFFER);
        if (der == NULL) {
            WOLFSSL_LEAVE("wolfssl_dhparams_to_der", MEMORY_E);
            err = 1;
        }
    }
    if (!err) {
        /* Encode DH parameters into DER buffer. */
        ret = wc_DhParamsToDer(key, der, &derSz);
        if (ret < 0) {
            WOLFSSL_ERROR_MSG("Failed to export DH params");
            err = 1;
        }
    }

    if (!err) {
        *out = der;
        der = NULL;
    }
    if (der != NULL) {
        XFREE(der, heap, DYNAMIC_TYPE_TMP_BUFFER);
    }

    return ret;
}

/* Writes the DH parameters in PEM format from "dh" out to the file pointer
 * passed in.
 *
 * @param [in]  fp  File pointer to write to.
 * @param [in]  dh  DH key to write.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_PEM_write_DHparams(XFILE fp, WOLFSSL_DH* dh)
{
    int ret = 1;
    int derSz;
    byte* derBuf = NULL;
    void* heap = NULL;

    WOLFSSL_ENTER("wolfSSL_PEM_write_DHparams");

    /* Validate parameters. */
    if ((fp == XBADFILE) || (dh == NULL)) {
        WOLFSSL_ERROR_MSG("Bad Function Arguments");
        ret = 0;
    }

    if (ret == 1) {
        DhKey* key = (DhKey*)dh->internal;
        if (key)
            heap = key->heap;
        if ((derSz = wolfssl_dhparams_to_der(dh, &derBuf, heap)) < 0) {
            WOLFSSL_ERROR_MSG("DER encoding failed");
            ret = 0;
        }
        if (derBuf == NULL) {
            WOLFSSL_ERROR_MSG("DER encoding failed to get buffer");
            ret = 0;
        }
    }
    if ((ret == 1) && (der_write_to_file_as_pem(derBuf, derSz, fp,
            DH_PARAM_TYPE, NULL) != 1)) {
        ret = 0;
    }

    /* Dispose of DER buffer. */
    XFREE(derBuf, heap, DYNAMIC_TYPE_TMP_BUFFER);

    WOLFSSL_LEAVE("wolfSSL_PEM_write_DHparams", ret);

    return ret;
}
#endif /* WOLFSSL_DH_EXTRA && !NO_FILESYSTEM */

#endif /* HAVE_LIGHTY || HAVE_STUNNEL || WOLFSSL_MYSQL_COMPATIBLE ||
        * OPENSSL_EXTRA */

/*
 * DH get/set APIs
 */

#ifdef OPENSSL_EXTRA

#if defined(WOLFSSL_QT) || defined(OPENSSL_ALL) \
    || defined(WOLFSSL_OPENSSH) || defined(OPENSSL_EXTRA)

/* Set the members of DhKey into WOLFSSL_DH
 * Specify elements to set via the 2nd parameter
 *
 * @param [in, out] dh   DH key to synchronize.
 * @param [in]      elm  Elements to synchronize.
 * @return  1 on success.
 * @return  -1 on failure.
 */
int SetDhExternal_ex(WOLFSSL_DH *dh, int elm)
{
    int ret = 1;
    DhKey *key = NULL;

    WOLFSSL_ENTER("SetDhExternal_ex");

    /* Validate parameters. */
    if ((dh == NULL) || (dh->internal == NULL)) {
        WOLFSSL_ERROR_MSG("dh key NULL error");
        ret = -1;
    }

    if (ret == 1) {
        /* Get the wolfSSL DH key. */
        key = (DhKey*)dh->internal;
    }

    if ((ret == 1) && (elm & ELEMENT_P)) {
        /* Set the prime. */
        if (wolfssl_bn_set_value(&dh->p, &key->p) != 1) {
            WOLFSSL_ERROR_MSG("dh param p error");
            ret = -1;
        }
    }
    if ((ret == 1) && (elm & ELEMENT_G)) {
        /* Set the generator. */
        if (wolfssl_bn_set_value(&dh->g, &key->g) != 1) {
            WOLFSSL_ERROR_MSG("dh param g error");
            ret = -1;
        }
    }
    if ((ret == 1) && (elm & ELEMENT_Q)) {
        /* Set the order. */
        if (wolfssl_bn_set_value(&dh->q, &key->q) != 1) {
            WOLFSSL_ERROR_MSG("dh param q error");
            ret = -1;
        }
    }
#ifdef WOLFSSL_DH_EXTRA
    if ((ret == 1) && (elm & ELEMENT_PRV)) {
        /* Set the private key. */
        if (wolfssl_bn_set_value(&dh->priv_key, &key->priv) != 1) {
            WOLFSSL_ERROR_MSG("No DH Private Key");
            ret = -1;
        }
    }
    if ((ret == 1) && (elm & ELEMENT_PUB)) {
        /* Set the public key. */
        if (wolfssl_bn_set_value(&dh->pub_key, &key->pub) != 1) {
            WOLFSSL_ERROR_MSG("No DH Public Key");
            ret = -1;
        }
    }
#endif /* WOLFSSL_DH_EXTRA */

    if (ret == 1) {
        /* On success record that the external values have been set. */
        dh->exSet = 1;
    }

    return ret;
}
/* Set the members of DhKey into WOLFSSL_DH
 * DhKey was populated from wc_DhKeyDecode
 * p, g, pub_key and priv_key are set.
 *
 * @param [in, out] dh   DH key to synchronize.
 * @return  1 on success.
 * @return  -1 on failure.
 */
int SetDhExternal(WOLFSSL_DH *dh)
{
    /* Assuming Q not required when using this API. */
    int elements = ELEMENT_P | ELEMENT_G | ELEMENT_PUB | ELEMENT_PRV;
    WOLFSSL_ENTER("SetDhExternal");
    return SetDhExternal_ex(dh, elements);
}
#endif /* WOLFSSL_QT || OPENSSL_ALL || WOLFSSL_OPENSSH || OPENSSL_EXTRA */

/* Set the internal/wolfSSL DH key with data from the external parts.
 *
 * @param [in, out] dh   DH key to synchronize.
 * @return  1 on success.
 * @return  -1 on failure.
 */
int SetDhInternal(WOLFSSL_DH* dh)
{
    int ret = 1;
    DhKey *key = NULL;

    WOLFSSL_ENTER("SetDhInternal");

    /* Validate parameters. */
    if ((dh == NULL) || (dh->p == NULL) || (dh->g == NULL)) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = -1;
    }
    if (ret == 1) {
        /* Get the wolfSSL DH key. */
        key = (DhKey*)dh->internal;

        /* Clear out key and initialize. */
        wc_FreeDhKey(key);
        if (wc_InitDhKey(key) != 0) {
            ret = -1;
        }
    }
    if (ret == 1) {
        /* Transfer prime. */
        if (wolfssl_bn_get_value(dh->p, &key->p) != 1) {
            ret = -1;
        }
    }
    if (ret == 1) {
        /* Transfer generator. */
        if (wolfssl_bn_get_value(dh->g, &key->g) != 1) {
            ret = -1;
        }
    }
#ifdef HAVE_FFDHE_Q
    /* Transfer order if available. */
    if ((ret == 1) && (dh->q != NULL)) {
        if (wolfssl_bn_get_value(dh->q, &key->q) != 1) {
            ret = -1;
        }
    }
#endif
#ifdef WOLFSSL_DH_EXTRA
    /* Transfer private key if available. */
    if ((ret == 1) && (dh->priv_key != NULL) &&
            (!wolfSSL_BN_is_zero(dh->priv_key))) {
        if (wolfssl_bn_get_value(dh->priv_key, &key->priv) != 1) {
            ret = -1;
        }
    }
    /* Transfer public key if available. */
    if ((ret == 1) && (dh->pub_key != NULL) &&
            (!wolfSSL_BN_is_zero(dh->pub_key))) {
        if (wolfssl_bn_get_value(dh->pub_key, &key->pub) != 1) {
            ret = -1;
        }
    }
#endif /* WOLFSSL_DH_EXTRA */

    if (ret == 1) {
        /* On success record that the internal values have been set. */
        dh->inSet = 1;
    }

    return ret;
}

/* Get the size, in bytes, of the DH key.
 *
 * Return code compliant with OpenSSL.
 *
 * @param [in] dh  DH key.
 * @return  -1 on error.
 * @return  Size of DH key in bytes on success.
 */
int wolfSSL_DH_size(WOLFSSL_DH* dh)
{
    int ret = -1;

    WOLFSSL_ENTER("wolfSSL_DH_size");

    /* Validate parameter. */
    if (dh != NULL) {
        /* Size of key is size of prime in bytes. */
        ret = wolfSSL_BN_num_bytes(dh->p);
    }

    return ret;
}

/**
 * Return parameters p, q and/or g of the DH key.
 *
 * @param [in]  dh  DH key to retrieve parameters from.
 * @param [out] p   Pointer to return prime in. May be NULL.
 * @param [out] q   Pointer to return order in. May be NULL.
 * @param [out] g   Pointer to return generator in. May be NULL.
 */
void wolfSSL_DH_get0_pqg(const WOLFSSL_DH *dh, const WOLFSSL_BIGNUM **p,
    const WOLFSSL_BIGNUM **q, const WOLFSSL_BIGNUM **g)
{
    WOLFSSL_ENTER("wolfSSL_DH_get0_pqg");

    if (dh != NULL) {
        /* Return prime if required. */
        if (p != NULL) {
            *p = dh->p;
        }
        /* Return order if required. */
        if (q != NULL) {
            *q = dh->q;
        }
        /* Return generator if required. */
        if (g != NULL) {
            *g = dh->g;
        }
    }
}

#if !defined(HAVE_FIPS) || (defined(HAVE_FIPS) && !defined(WOLFSSL_DH_EXTRA)) \
 || (defined(HAVE_FIPS_VERSION) && FIPS_VERSION_GT(2,0))
#if defined(OPENSSL_ALL) || \
    defined(OPENSSL_VERSION_NUMBER) && OPENSSL_VERSION_NUMBER >= 0x10100000L
/* Sets the parameters p, g and optionally q into the DH key.
 *
 * Ownership of p, q and g get taken over by "dh" on success and should be
 * free'd with a call to wolfSSL_DH_free -- not individually.
 *
 * @param [in, out] dh   DH key to set.
 * @param [in]      p    Prime value to set. May be NULL when value already
 *                       present.
 * @param [in]      q    Order value to set. May be NULL.
 * @param [in]      g    Generator value to set. May be NULL when value already
 *                       present.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_DH_set0_pqg(WOLFSSL_DH *dh, WOLFSSL_BIGNUM *p,
    WOLFSSL_BIGNUM *q, WOLFSSL_BIGNUM *g)
{
    int ret = 1;

    WOLFSSL_ENTER("wolfSSL_DH_set0_pqg");

    /* Validate parameters - q is optional. */
    if (dh == NULL) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = 0;
    }
    /* p can be NULL if we already have one set. */
    if ((ret == 1) && (p == NULL) && (dh->p == NULL)) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = 0;
    }
    /* g can be NULL if we already have one set. */
    if ((ret == 1) && (g == NULL) && (dh->g == NULL)) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = 0;
    }

    if (ret == 1) {
        /* Invalidate internal key. */
        dh->inSet = 0;

        /* Free external representation of parameters and set with those passed
         * in. */
        if (p != NULL) {
            wolfSSL_BN_free(dh->p);
            dh->p = p;
        }
        if (q != NULL) {
            wolfSSL_BN_free(dh->q);
            dh->q = q;
        }
        if (g != NULL) {
            wolfSSL_BN_free(dh->g);
            dh->g = g;
        }
        /* External DH key parameters were set. */
        dh->exSet = 1;

        /* Set internal/wolfSSL DH key as well. */
        if (SetDhInternal(dh) != 1) {
            WOLFSSL_ERROR_MSG("Unable to set internal DH key");
            /* Don't keep parameters on failure. */
            dh->p = NULL;
            dh->q = NULL;
            dh->g = NULL;
            /* Internal and external DH key not set. */
            dh->inSet = 0;
            dh->exSet = 0;
            ret = 0;
        }
    }

    return ret;
}

/* Set the length of the DH private key in bits.
 *
 * Length field is checked at generation.
 *
 * @param [in, out] dh   DH key to set.
 * @param [in]      len  Length of DH private key in bytes.
 * @return  0 on failure.
 * @return  1 on success.
 */
int wolfSSL_DH_set_length(WOLFSSL_DH *dh, long len)
{
    int ret = 1;

    WOLFSSL_ENTER("wolfSSL_DH_set_length");

    /* Validate parameter. */
    if (dh == NULL) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = 0;
    }
    else {
        /* Store length. */
        dh->length = (int)len;
    }

    return ret;
}
#endif /* OPENSSL_ALL || (v1.1.0 or later) */
#endif

/* Get the public and private keys requested.
 *
 * @param [in]  dh         DH key to get keys from.
 * @param [out] pub_key    Pointer to return public key in. May be NULL.
 * @param [out] priv_key   Pointer to return private key in. May be NULL.
 */
void wolfSSL_DH_get0_key(const WOLFSSL_DH *dh, const WOLFSSL_BIGNUM **pub_key,
    const WOLFSSL_BIGNUM **priv_key)
{
    WOLFSSL_ENTER("wolfSSL_DH_get0_key");

    /* Get only when valid DH passed in. */
    if (dh != NULL) {
        /* Return public key if required and available. */
        if ((pub_key != NULL) && (dh->pub_key != NULL)) {
            *pub_key = dh->pub_key;
        }
        /* Return private key if required and available. */
        if ((priv_key != NULL) && (dh->priv_key != NULL)) {
            *priv_key = dh->priv_key;
        }
    }
}

/* Set the public and/or private key.
 *
 * @param [in, out] dh        DH key to have keys set into.
 * @param [in]      pub_key   Public key to set. May be NULL.
 * @param [in]      priv_key  Private key to set. May be NULL.
 * @return  0 on failure.
 * @return  1 on success.
 */
int wolfSSL_DH_set0_key(WOLFSSL_DH *dh, WOLFSSL_BIGNUM *pub_key,
    WOLFSSL_BIGNUM *priv_key)
{
    int ret = 1;
#ifdef WOLFSSL_DH_EXTRA
    DhKey *key = NULL;
#endif

    WOLFSSL_ENTER("wolfSSL_DH_set0_key");

    /* Validate parameters. */
    if (dh == NULL) {
        ret = 0;
    }
#ifdef WOLFSSL_DH_EXTRA
    else {
        key = (DhKey*)dh->internal;
    }
#endif

    /* Replace public key when one passed in. */
    if ((ret == 1) && (pub_key != NULL)) {
        wolfSSL_BN_free(dh->pub_key);
        dh->pub_key = pub_key;
    #ifdef WOLFSSL_DH_EXTRA
        if (wolfssl_bn_get_value(dh->pub_key, &key->pub) != 1) {
            ret = 0;
        }
    #endif
    }

    /* Replace private key when one passed in. */
    if ((ret == 1) && (priv_key != NULL)) {
        wolfSSL_BN_clear_free(dh->priv_key);
        dh->priv_key = priv_key;
    #ifdef WOLFSSL_DH_EXTRA
        if (wolfssl_bn_get_value(dh->priv_key, &key->priv) != 1) {
            ret = 0;
        }
    #endif
    }

    return ret;
}

#endif /* OPENSSL_EXTRA */

/*
 * DH check APIs
 */

#ifdef OPENSSL_EXTRA

#ifndef NO_CERTS

#ifdef OPENSSL_ALL
/* Check whether BN number is a prime.
 *
 * @param [in]  n        Number to check.
 * @param [out] isPrime  MP_YES when prime and MP_NO when not.
 * @return  1 on success.
 * @return  0 on error.
 */
static int wolfssl_dh_check_prime(WOLFSSL_BIGNUM* n, int* isPrime)
{
    int ret = 1;
#ifdef WOLFSSL_SMALL_STACK
    WC_RNG* tmpRng = NULL;
#else
    WC_RNG  tmpRng[1];
#endif
    WC_RNG* rng;
    int localRng;

    /* Make an RNG with tmpRng or get global. */
    rng = wolfssl_make_rng(tmpRng, &localRng);
    if (rng == NULL) {
        ret = 0;
    }
    if (ret == 1) {
        mp_int* prime = (mp_int*)n->internal;

        if (mp_prime_is_prime_ex(prime, 8, isPrime, rng) != 0) {
            ret = 0;
        }
        /* Free local random number generator if created. */
        if (localRng) {
            wc_FreeRng(rng);
        #ifdef WOLFSSL_SMALL_STACK
            XFREE(rng, NULL, DYNAMIC_TYPE_TMP_BUFFER);
        #endif
        }
    }

    return ret;
}

/* Checks the Diffie-Hellman parameters.
 *
 * Checks that the generator and prime are available.
 * Checks that the prime is prime.
 * OpenSSL expects codes to be non-NULL.
 *
 * @param [in]  dh     DH key to check.
 * @param [out] codes  Codes of checks that failed.
 * @return  1 on success.
 * @return  0 when DH is NULL, there were errors or failed to create a random
 *          number generator.
 */
int wolfSSL_DH_check(const WOLFSSL_DH *dh, int *codes)
{
    int ret = 1;
    int errors = 0;

    WOLFSSL_ENTER("wolfSSL_DH_check");

    /* Validate parameters. */
    if (dh == NULL) {
        ret = 0;
    }

    /* Check generator available. */
    if ((ret == 1) && ((dh->g == NULL) || (dh->g->internal == NULL))) {
        errors |= DH_NOT_SUITABLE_GENERATOR;
    }

    if (ret == 1) {
        /* Check prime available. */
        if ((dh->p == NULL) || (dh->p->internal == NULL)) {
            errors |= DH_CHECK_P_NOT_PRIME;
        }
        else {
            /* Test if dh->p is prime. */
            int isPrime = MP_NO;
            ret = wolfssl_dh_check_prime(dh->p, &isPrime);
            /* Set error code if parameter p is not prime. */
            if ((ret == 1) && (isPrime != MP_YES)) {
                errors |= DH_CHECK_P_NOT_PRIME;
            }
        }
    }

    /* Return errors when user wants exact issues. */
    if (codes != NULL) {
        *codes = errors;
    }
    else if (errors) {
        ret = 0;
    }

    return ret;
}

#endif /* OPENSSL_ALL */

#endif /* !NO_CERTS */

#endif /* OPENSSL_EXTRA */

/*
 * DH generate APIs
 */

#if defined(OPENSSL_ALL) || (defined(OPENSSL_EXTRA) && \
    (defined(HAVE_STUNNEL) || defined(WOLFSSL_NGINX) || \
    defined(HAVE_LIGHTY) || defined(WOLFSSL_HAPROXY) || \
    defined(WOLFSSL_OPENSSH) || defined(HAVE_SBLIM_SFCB)))

#if defined(WOLFSSL_KEY_GEN) && !defined(HAVE_SELFTEST)
/* Generate DH parameters.
 *
 * @param [in] prime_len  Length of prime in bits.
 * @param [in] generator  Generator value to use.
 * @param [in] callback   Called with progress information. Unused.
 * @param [in] cb_arg     User callback argument. Unused.
 * @return  NULL on failure.
 * @return  DH key on success.
 */
WOLFSSL_DH *wolfSSL_DH_generate_parameters(int prime_len, int generator,
                           void (*callback) (int, int, void *), void *cb_arg)
{
    WOLFSSL_DH* dh = NULL;

    WOLFSSL_ENTER("wolfSSL_DH_generate_parameters");
    /* Not supported by wolfSSl APIs. */
    (void)callback;
    (void)cb_arg;

    /* Create an empty DH key. */
    if ((dh = wolfSSL_DH_new()) == NULL) {
        WOLFSSL_ERROR_MSG("wolfSSL_DH_new error");
    }
    /* Generate parameters into DH key. */
    else if (wolfSSL_DH_generate_parameters_ex(dh, prime_len, generator, NULL)
            != 1) {
        WOLFSSL_ERROR_MSG("wolfSSL_DH_generate_parameters_ex error");
        wolfSSL_DH_free(dh);
        dh = NULL;
    }

    return dh;
}

/* Generate DH parameters.
 *
 * @param [in] dh         DH key to generate parameters into.
 * @param [in] prime_len  Length of prime in bits.
 * @param [in] generator  Generator value to use.
 * @param [in] callback   Called with progress information. Unused.
 * @param [in] cb_arg     User callback argument. Unused.
 * @return  0 on failure.
 * @return  1 on success.
 */
int wolfSSL_DH_generate_parameters_ex(WOLFSSL_DH* dh, int prime_len,
    int generator, void (*callback) (int, int, void *))
{
    int ret = 1;
    DhKey* key = NULL;
#ifdef WOLFSSL_SMALL_STACK
    WC_RNG* tmpRng = NULL;
#else
    WC_RNG  tmpRng[1];
#endif
    WC_RNG* rng = NULL;
    int localRng = 0;

    WOLFSSL_ENTER("wolfSSL_DH_generate_parameters_ex");
    /* Not supported by wolfSSL APIs. */
    (void)callback;
    (void)generator;

    /* Validate parameters. */
    if (dh == NULL) {
        WOLFSSL_ERROR_MSG("Bad parameter");
        ret = 0;
    }

    if (ret == 1) {
        /* Make an RNG with tmpRng or get global. */
        rng = wolfssl_make_rng(tmpRng, &localRng);
        if (rng == NULL) {
            WOLFSSL_ERROR_MSG("No RNG to use");
            ret = 0;
        }
    }

    if (ret == 1) {
        /* Get internal/wolfSSL DH key. */
        key = (DhKey*)dh->internal;

        /* Clear out data from internal DH key. */
        wc_FreeDhKey(key);
        /* Re-initialize internal DH key. */
        if (wc_InitDhKey(key) != 0) {
            ret = 0;
        }
    }
    if (ret == 1) {
        /* Generate parameters into internal DH key. */
        if (wc_DhGenerateParams(rng, prime_len, key) != 0) {
            WOLFSSL_ERROR_MSG("wc_DhGenerateParams error");
            ret = 0;
        }
    }

    /* Free local random number generator if created. */
    if (localRng) {
        wc_FreeRng(rng);
    #ifdef WOLFSSL_SMALL_STACK
        XFREE(rng, NULL, DYNAMIC_TYPE_TMP_BUFFER);
    #endif
    }

    if (ret == 1) {
        /* Internal parameters set by generation. */
        dh->inSet = 1;

        WOLFSSL_MSG("wolfSSL does not support using a custom generator.");

        /* Synchronize the external to the internal parameters. */
        if (SetDhExternal(dh) != 1) {
            WOLFSSL_ERROR_MSG("SetDhExternal error");
            ret = 0;
        }
    }

    return ret;
}
#endif /* WOLFSSL_KEY_GEN && !HAVE_SELFTEST */

#endif /* OPENSSL_ALL || (OPENSSL_EXTRA && (HAVE_STUNNEL || WOLFSSL_NGINX ||
        * HAVE_LIGHTY || WOLFSSL_HAPROXY || WOLFSSL_OPENSSH ||
        * HAVE_SBLIM_SFCB)) */

#ifdef OPENSSL_EXTRA

#if !defined(HAVE_FIPS) || (defined(HAVE_FIPS) && !defined(WOLFSSL_DH_EXTRA)) \
 || (defined(HAVE_FIPS_VERSION) && FIPS_VERSION_GT(2,0))
/* Generate a public/private key pair base on parameters.
 *
 * @param [in, out] dh  DH key to generate keys into.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_DH_generate_key(WOLFSSL_DH* dh)
{
    int     ret    = 1;
    word32  pubSz  = 0;
    word32  privSz = 0;
    int     localRng = 0;
    WC_RNG* rng    = NULL;
#ifdef WOLFSSL_SMALL_STACK
    WC_RNG* tmpRng = NULL;
#else
    WC_RNG  tmpRng[1];
#endif
    unsigned char* pub    = NULL;
    unsigned char* priv   = NULL;

    WOLFSSL_ENTER("wolfSSL_DH_generate_key");

    /* Validate parameters. */
    if ((dh == NULL) || (dh->p == NULL) || (dh->g == NULL)) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = 0;
    }

    /* Synchronize the external and internal parameters. */
    if ((ret == 1) && (dh->inSet == 0) && (SetDhInternal(dh) != 1)) {
        WOLFSSL_ERROR_MSG("Bad DH set internal");
        ret = 0;
    }

    if (ret == 1) {
        /* Make a new RNG or use global. */
        rng = wolfssl_make_rng(tmpRng, &localRng);
        /* Check we have a random number generator. */
        if (rng == NULL) {
            ret = 0;
        }
    }

    if (ret == 1) {
        /* Get the size of the prime in bytes. */
        pubSz = (word32)wolfSSL_BN_num_bytes(dh->p);
        if (pubSz == 0) {
            WOLFSSL_ERROR_MSG("Prime parameter invalid");
            ret = 0;
        }
    }
    if (ret == 1) {
        /* Private key size can be as much as the size of the prime. */
        if (dh->length) {
            privSz = (word32)(dh->length / 8); /* to bytes */
        }
        else {
            privSz = pubSz;
        }
        /* Allocate public and private key arrays. */
        pub = (unsigned char*)XMALLOC(pubSz, NULL, DYNAMIC_TYPE_PUBLIC_KEY);
        priv = (unsigned char*)XMALLOC(privSz, NULL, DYNAMIC_TYPE_PRIVATE_KEY);
        if (pub == NULL || priv == NULL) {
            WOLFSSL_ERROR_MSG("Unable to malloc memory");
            ret = 0;
        }
    }
    if (ret == 1) {
        /* Dispose of old public and private keys. */
        wolfSSL_BN_free(dh->pub_key);
        wolfSSL_BN_free(dh->priv_key);

        /* Allocate new public and private keys. */
        dh->pub_key = wolfSSL_BN_new();
        dh->priv_key = wolfSSL_BN_new();
        if (dh->pub_key == NULL) {
            WOLFSSL_ERROR_MSG("Bad DH new pub");
            ret = 0;
        }
        if (dh->priv_key == NULL) {
            WOLFSSL_ERROR_MSG("Bad DH new priv");
            ret = 0;
        }
    }

    PRIVATE_KEY_UNLOCK();
    /* Generate public and private keys into arrays. */
    if ((ret == 1) && (wc_DhGenerateKeyPair((DhKey*)dh->internal, rng, priv,
            &privSz, pub, &pubSz) < 0)) {
        WOLFSSL_ERROR_MSG("Bad wc_DhGenerateKeyPair");
        ret = 0;
    }
    /* Set public key from array. */
    if ((ret == 1) && (wolfSSL_BN_bin2bn(pub, (int)pubSz, dh->pub_key) ==
            NULL)) {
        WOLFSSL_ERROR_MSG("Bad DH bn2bin error pub");
        ret = 0;
    }
    /* Set private key from array. */
    if ((ret == 1) && (wolfSSL_BN_bin2bn(priv, (int)privSz, dh->priv_key) ==
            NULL)) {
        WOLFSSL_ERROR_MSG("Bad DH bn2bin error priv");
        ret = 0;
    }
    PRIVATE_KEY_LOCK();

    if (localRng) {
        /* Free an initialized local random number generator. */
        wc_FreeRng(rng);
    #ifdef WOLFSSL_SMALL_STACK
        XFREE(rng, NULL, DYNAMIC_TYPE_RNG);
    #endif
    }
    /* Dispose of allocated data. */
    XFREE(pub,  NULL, DYNAMIC_TYPE_PUBLIC_KEY);
    XFREE(priv, NULL, DYNAMIC_TYPE_PRIVATE_KEY);

    return ret;
}


/* Compute the shared key from the private key and peer's public key.
 *
 * Return code compliant with OpenSSL.
 * OpenSSL returns 0 when number of bits in p are smaller than minimum
 * supported.
 *
 * @param [out] key       Buffer to place shared key.
 * @param [in]  otherPub  Peer's public key.
 * @param [in]  dh        DH key containing private key.
 * @return  -1 on error.
 * @return  Size of shared secret in bytes on success.
 */
int wolfSSL_DH_compute_key(unsigned char* key, const WOLFSSL_BIGNUM* otherPub,
    WOLFSSL_DH* dh)
{
    int            ret    = 0;
    word32         keySz  = 0;
    int            pubSz  = MAX_DHKEY_SZ;
    int            privSz = MAX_DHKEY_SZ;
    int            sz     = 0;
#ifdef WOLFSSL_SMALL_STACK
    unsigned char* pub    = NULL;
    unsigned char* priv   = NULL;
#else
    unsigned char  pub [MAX_DHKEY_SZ];
    unsigned char  priv[MAX_DHKEY_SZ];
#endif

    WOLFSSL_ENTER("wolfSSL_DH_compute_key");

    /* Validate parameters. */
    if ((dh == NULL) || (dh->priv_key == NULL) || (otherPub == NULL)) {
        WOLFSSL_ERROR_MSG("Bad function arguments");
        ret = -1;
    }
    /* Get the maximum size of computed DH key. */
    if ((ret == 0) && ((keySz = (word32)DH_size(dh)) == 0)) {
        WOLFSSL_ERROR_MSG("Bad DH_size");
        ret = -1;
    }
    if (ret == 0) {
        /* Validate the size of the private key. */
        sz = wolfSSL_BN_num_bytes(dh->priv_key);
        if (sz > (int)privSz) {
            WOLFSSL_ERROR_MSG("Bad priv internal size");
            ret = -1;
        }
    }
    if (ret == 0) {
    #ifdef WOLFSSL_SMALL_STACK
        /* Keep real private key size to minimize amount allocated. */
        privSz = sz;
    #endif

        /* Validate the size of the public key. */
        sz = wolfSSL_BN_num_bytes(otherPub);
        if (sz > pubSz) {
            WOLFSSL_ERROR_MSG("Bad otherPub size");
            ret = -1;
        }
    }

    if (ret == 0) {
    #ifdef WOLFSSL_SMALL_STACK
        /* Allocate memory for the public key array. */
        pub = (unsigned char*)XMALLOC((size_t)sz, NULL,
            DYNAMIC_TYPE_PUBLIC_KEY);
        if (pub == NULL)
            ret = -1;
    }
    if (ret == 0) {
        /* Allocate memory for the private key array. */
        priv = (unsigned char*)XMALLOC((size_t)privSz, NULL,
            DYNAMIC_TYPE_PRIVATE_KEY);
        if (priv == NULL) {
            ret = -1;
        }
    }
    if (ret == 0) {
    #endif
        /* Get the private key into the array. */
        privSz = wolfSSL_BN_bn2bin(dh->priv_key, priv);
        if (privSz <= 0) {
            ret = -1;
        }
    }
    if (ret == 0) {
        /* Get the public key into the array. */
        pubSz  = wolfSSL_BN_bn2bin(otherPub, pub);
        if (pubSz <= 0) {
            ret = -1;
        }
    }
    /* Synchronize the external into the internal parameters. */
    if ((ret == 0) && ((dh->inSet == 0) && (SetDhInternal(dh) != 1))) {
        WOLFSSL_ERROR_MSG("Bad DH set internal");
        ret = -1;
    }

    PRIVATE_KEY_UNLOCK();
    /* Calculate shared secret from private and public keys. */
    if ((ret == 0) && (wc_DhAgree((DhKey*)dh->internal, key, &keySz, priv,
            (word32)privSz, pub, (word32)pubSz) < 0)) {
        WOLFSSL_ERROR_MSG("wc_DhAgree failed");
        ret = -1;
    }
    if (ret == 0) {
        /* Return actual length. */
        ret = (int)keySz;
    }
    PRIVATE_KEY_LOCK();

#ifdef WOLFSSL_SMALL_STACK
    if (priv != NULL)
#endif
    {
        /* Zeroize sensitive data. */
        ForceZero(priv, (word32)privSz);
    }
#ifdef WOLFSSL_SMALL_STACK
    XFREE(pub,  NULL, DYNAMIC_TYPE_PUBLIC_KEY);
    XFREE(priv, NULL, DYNAMIC_TYPE_PRIVATE_KEY);
#endif

    WOLFSSL_LEAVE("wolfSSL_DH_compute_key", ret);

    return ret;
}
#endif /* !HAVE_FIPS || (HAVE_FIPS && !WOLFSSL_DH_EXTRA) ||
        * HAVE_FIPS_VERSION > 2 */

#endif /* OPENSSL_EXTRA */

#endif /* NO_DH */

/*******************************************************************************
 * END OF DH API
 ******************************************************************************/


/*******************************************************************************
 * START OF EC API
 ******************************************************************************/

#ifdef HAVE_ECC

#if defined(OPENSSL_EXTRA)

/* Start EC_curve */

/* Get the NIST name for the numeric ID.
 *
 * @param [in] nid  Numeric ID of an EC curve.
 * @return  String representing NIST name of EC curve on success.
 * @return  NULL on error.
 */
const char* wolfSSL_EC_curve_nid2nist(int nid)
{
    const char* name = NULL;
    const WOLF_EC_NIST_NAME* nist_name;

    /* Attempt to find the curve info matching the NID passed in. */
    for (nist_name = kNistCurves; nist_name->name != NULL; nist_name++) {
        if (nist_name->nid == nid) {
            /* NID found - return name. */
            name = nist_name->name;
            break;
        }
    }

    return name;
}

/* Get the numeric ID for the NIST name.
 *
 * @param [in] name  NIST name of EC curve.
 * @return  NID matching NIST name on success.
 * @return  0 on error.
 */
int wolfSSL_EC_curve_nist2nid(const char* name)
{
    int nid = 0;
    const WOLF_EC_NIST_NAME* nist_name;

    /* Attempt to find the curve info matching the NIST name passed in. */
    for (nist_name = kNistCurves; nist_name->name != NULL; nist_name++) {
        if (XSTRCMP(nist_name->name, name) == 0) {
            /* Name found - return NID. */
            nid = nist_name->nid;
            break;
        }
    }

    return nid;
}

#endif /* OPENSSL_EXTRA */

/* End EC_curve */

/* Start EC_METHOD */

#if defined(OPENSSL_EXTRA) || defined(OPENSSL_EXTRA_X509_SMALL)
/* Get the EC method of the EC group object.
 *
 * wolfSSL doesn't use method tables. Implementation used is dependent upon
 * the NID.
 *
 * @param [in] group  EC group object.
 * @return  EC method.
 */
const WOLFSSL_EC_METHOD* wolfSSL_EC_GROUP_method_of(
    const WOLFSSL_EC_GROUP *group)
{
    /* No method table used so just return the same object. */
    return group;
}

/* Get field type for method.
 *
 * Only prime fields are supported.
 *
 * @param [in] meth  EC method.
 * @return  X9.63 prime field NID on success.
 * @return  0 on error.
 */
int wolfSSL_EC_METHOD_get_field_type(const WOLFSSL_EC_METHOD *meth)
{
    int nid = 0;

    if (meth != NULL) {
        /* Only field type supported by code base. */
        nid = NID_X9_62_prime_field;
    }

    return nid;
}
#endif /* OPENSSL_EXTRA || OPENSSL_EXTRA_X509_SMALL */

/* End EC_METHOD */

/* Start EC_GROUP */

#if defined(OPENSSL_EXTRA) || defined(OPENSSL_EXTRA_X509_SMALL)
/* Converts ECC curve enum values in ecc_curve_id to the associated OpenSSL NID
 * value.
 *
 * @param [in] n  ECC curve id.
 * @return  ECC curve NID (OpenSSL compatible value).
 */
int EccEnumToNID(int n)
{
    WOLFSSL_ENTER("EccEnumToNID");

    switch(n) {
        case ECC_SECP192R1:
            return NID_X9_62_prime192v1;
        case ECC_PRIME192V2:
            return NID_X9_62_prime192v2;
        case ECC_PRIME192V3:
            return NID_X9_62_prime192v3;
        case ECC_PRIME239V1:
            return NID_X9_62_prime239v1;
        case ECC_PRIME239V2:
            return NID_X9_62_prime239v2;
        case ECC_PRIME239V3:
            return NID_X9_62_prime239v3;
        case ECC_SECP256R1:
            return NID_X9_62_prime256v1;
        case ECC_SECP112R1:
            return NID_secp112r1;
        case ECC_SECP112R2:
            return NID_secp112r2;
        case ECC_SECP128R1:
            return NID_secp128r1;
        case ECC_SECP128R2:
            return NID_secp128r2;
        case ECC_SECP160R1:
            return NID_secp160r1;
        case ECC_SECP160R2:
            return NID_secp160r2;
        case ECC_SECP224R1:
            return NID_secp224r1;
        case ECC_SECP384R1:
            return NID_secp384r1;
        case ECC_SECP521R1:
            return NID_secp521r1;
        case ECC_SECP160K1:
            return NID_secp160k1;
        case ECC_SECP192K1:
            return NID_secp192k1;
        case ECC_SECP224K1:
            return NID_secp224k1;
        case ECC_SECP256K1:
            return NID_secp256k1;
        case ECC_BRAINPOOLP160R1:
            return NID_brainpoolP160r1;
        case ECC_BRAINPOOLP192R1:
            return NID_brainpoolP192r1;
        case ECC_BRAINPOOLP224R1:
            return NID_brainpoolP224r1;
        case ECC_BRAINPOOLP256R1:
            return NID_brainpoolP256r1;
        case ECC_BRAINPOOLP320R1:
            return NID_brainpoolP320r1;
        case ECC_BRAINPOOLP384R1:
            return NID_brainpoolP384r1;
        case ECC_BRAINPOOLP512R1:
            return NID_brainpoolP512r1;
    #ifdef WOLFSSL_SM2
        case ECC_SM2P256V1:
            return NID_sm2;
    #endif
        default:
            WOLFSSL_MSG("NID not found");
            return -1;
    }
}
#endif /* OPENSSL_EXTRA || OPENSSL_EXTRA_X509_SMALL */

#if defined(OPENSSL_EXTRA) || defined(WOLFSSL_WPAS_SMALL)
/* Converts OpenSSL NID of EC curve to the enum value in ecc_curve_id
 *
 * Used by ecc_sets[].
 *
 * @param [in] n  OpenSSL NID of EC curve.
 * @return  wolfCrypt EC curve id.
 * @return  -1 on error.
 */
int NIDToEccEnum(int nid)
{
    /* -1 on error. */
    int id = -1;

    WOLFSSL_ENTER("NIDToEccEnum");

    switch (nid) {
        case NID_X9_62_prime192v1:
            id = ECC_SECP192R1;
            break;
        case NID_X9_62_prime192v2:
            id = ECC_PRIME192V2;
            break;
        case NID_X9_62_prime192v3:
            id = ECC_PRIME192V3;
            break;
        case NID_X9_62_prime239v1:
            id = ECC_PRIME239V1;
            break;
        case NID_X9_62_prime239v2:
            id = ECC_PRIME239V2;
            break;
        case NID_X9_62_prime239v3:
            id = ECC_PRIME239V3;
            break;
        case NID_X9_62_prime256v1:
            id = ECC_SECP256R1;
            break;
        case NID_secp112r1:
            id = ECC_SECP112R1;
            break;
        case NID_secp112r2:
            id = ECC_SECP112R2;
            break;
        case NID_secp128r1:
            id = ECC_SECP128R1;
            break;
        case NID_secp128r2:
            id = ECC_SECP128R2;
            break;
        case NID_secp160r1:
            id = ECC_SECP160R1;
            break;
        case NID_secp160r2:
            id = ECC_SECP160R2;
            break;
        case NID_secp224r1:
            id = ECC_SECP224R1;
            break;
        case NID_secp384r1:
            id = ECC_SECP384R1;
            break;
        case NID_secp521r1:
            id = ECC_SECP521R1;
            break;
        case NID_secp160k1:
            id = ECC_SECP160K1;
            break;
        case NID_secp192k1:
            id = ECC_SECP192K1;
            break;
        case NID_secp224k1:
            id = ECC_SECP224K1;
            break;
        case NID_secp256k1:
            id = ECC_SECP256K1;
            break;
        case NID_brainpoolP160r1:
            id = ECC_BRAINPOOLP160R1;
            break;
        case NID_brainpoolP192r1:
            id = ECC_BRAINPOOLP192R1;
            break;
        case NID_brainpoolP224r1:
            id = ECC_BRAINPOOLP224R1;
            break;
        case NID_brainpoolP256r1:
            id = ECC_BRAINPOOLP256R1;
            break;
        case NID_brainpoolP320r1:
            id = ECC_BRAINPOOLP320R1;
            break;
        case NID_brainpoolP384r1:
            id = ECC_BRAINPOOLP384R1;
            break;
        case NID_brainpoolP512r1:
            id = ECC_BRAINPOOLP512R1;
            break;
        default:
            WOLFSSL_MSG("NID not found");
    }

    return id;
}

/* Set the fields of the EC group based on numeric ID.
 *
 * @param [in, out] group  EC group.
 * @param [in]      nid    Numeric ID of an EC curve.
 */
static void ec_group_set_nid(WOLFSSL_EC_GROUP* group, int nid)
{
    int eccEnum;
    int realNid;

    /* Convert ecc_curve_id enum to NID. */
    if ((realNid = EccEnumToNID(nid)) != -1) {
        /* ecc_curve_id enum passed in - have real NID value set. */
        eccEnum = nid;
    }
    else {
        /* NID passed in is OpenSSL type. */
        realNid = nid;
        /* Convert NID to ecc_curve_id enum. */
        eccEnum = NIDToEccEnum(nid);
    }

    /* Set the numeric ID of the curve */
    group->curve_nid = realNid;
    /* Initialize index to -1 (i.e. wolfCrypt doesn't support curve). */
    group->curve_idx = -1;

    /* Find index and OID sum for curve if wolfCrypt supports it. */
    if (eccEnum != -1) {
        int i;

        /* Find id and set the internal curve idx and OID sum. */
        for (i = 0; ecc_sets[i].size != 0; i++) {
            if (ecc_sets[i].id == eccEnum) {
                /* Found id in wolfCrypt supported EC curves. */
                group->curve_idx = i;
                group->curve_oid = (int)ecc_sets[i].oidSum;
                break;
            }
        }
    }
}

/* Create a new EC group with the numeric ID for an EC curve.
 *
 * @param [in] nid  Numeric ID of an EC curve.
 * @return  New, allocated EC group on success.
 * @return  NULL on error.
 */
WOLFSSL_EC_GROUP* wolfSSL_EC_GROUP_new_by_curve_name(int nid)
{
    int err = 0;
    WOLFSSL_EC_GROUP* group;

    WOLFSSL_ENTER("wolfSSL_EC_GROUP_new_by_curve_name");

    /* Allocate EC group. */
    group = (WOLFSSL_EC_GROUP*)XMALLOC(sizeof(WOLFSSL_EC_GROUP), NULL,
        DYNAMIC_TYPE_ECC);
    if (group == NULL) {
        WOLFSSL_MSG("wolfSSL_EC_GROUP_new_by_curve_name malloc failure");
        err = 1;
    }

    if (!err) {
        /* Reset all fields. */
        XMEMSET(group, 0, sizeof(WOLFSSL_EC_GROUP));

        /* Set the fields of group based on the numeric ID. */
        ec_group_set_nid(group, nid);
    }

    return group;
}
#endif /* OPENSSL_EXTRA || WOLFSSL_WPAS_SMALL */

#if defined(OPENSSL_EXTRA) || defined(OPENSSL_EXTRA_X509_SMALL)
/* Dispose of the EC group.
 *
 * Cannot use group after this call.
 *
 * @param [in] group  EC group to free.
 */
void wolfSSL_EC_GROUP_free(WOLFSSL_EC_GROUP *group)
{
    WOLFSSL_ENTER("wolfSSL_EC_GROUP_free");

    /* Dispose of EC group. */
    XFREE(group, NULL, DYNAMIC_TYPE_ECC);
}
#endif /* OPENSSL_EXTRA || OPENSSL_EXTRA_X509_SMALL */

#ifdef OPENSSL_EXTRA
#ifndef NO_BIO

/* Creates an EC group from the DER encoding.
 *
 * Only named curves supported.
 *
 * @param [out] group  Reference to EC group object.
 * @param [in]  in     Buffer holding DER encoding of curve.
 * @param [in]  inSz   Length of data in buffer.
 * @return  EC group on success.
 * @return  NULL on error.
 */
static WOLFSSL_EC_GROUP* wolfssl_ec_group_d2i(WOLFSSL_EC_GROUP** group,
    const unsigned char* in, long inSz)
{
    int err = 0;
    WOLFSSL_EC_GROUP* ret = NULL;
    word32 idx = 0;
    word32 oid = 0;
    int id = 0;

    /* Use the group passed in. */
    if ((group != NULL) && (*group != NULL)) {
        ret = *group;
    }

    /* Only support named curves. */
    if (in[0] != ASN_OBJECT_ID) {
        WOLFSSL_ERROR_MSG("Invalid or unsupported encoding");
        err = 1;
    }
    /* Decode the OBJECT ID - expecting an EC curve OID. */
    if ((!err) && (GetObjectId(in, &idx, &oid, oidCurveType, (word32)inSz) !=
            0)) {
        err = 1;
    }
    if (!err) {
        /* Get the internal ID for OID. */
        id = wc_ecc_get_oid(oid, NULL, NULL);
        if (id < 0) {
            err = 1;
        }
    }
    if (!err) {
        /* Get the NID for the internal ID. */
        int nid = EccEnumToNID(id);
        if (ret == NULL) {
            /* Create a new EC group with the numeric ID. */
            ret = wolfSSL_EC_GROUP_new_by_curve_name(nid);
            if (ret == NULL) {
                err = 1;
            }
        }
        else {
            ec_group_set_nid(ret, nid);
        }
    }
    if ((!err) && (group != NULL)) {
        /* Return the EC group through reference. */
        *group = ret;
    }

    if (err) {
        if ((ret != NULL) && (ret != *group)) {
            wolfSSL_EC_GROUP_free(ret);
        }
        ret = NULL;
    }
    return ret;
}

/* Creates a new EC group from the PEM encoding in the BIO.
 *
 * @param [in]  bio    BIO to read PEM encoding from.
 * @param [out] group  Reference to EC group object.
 * @param [in]  cb     Password callback when PEM encrypted.
 * @param [in]  pass   NUL terminated string for passphrase when PEM encrypted.
 * @return  EC group on success.
 * @return  NULL on error.
 */
WOLFSSL_EC_GROUP* wolfSSL_PEM_read_bio_ECPKParameters(WOLFSSL_BIO* bio,
    WOLFSSL_EC_GROUP** group, wc_pem_password_cb* cb, void* pass)
{
    int err = 0;
    WOLFSSL_EC_GROUP* ret = NULL;
    DerBuffer*        der = NULL;
    int               keyFormat = 0;

     if (bio == NULL) {
         err = 1;
     }

    /* Read parameters from BIO and convert PEM to DER. */
    if ((!err) && (pem_read_bio_key(bio, cb, pass, ECC_PARAM_TYPE,
            &keyFormat, &der) < 0)) {
        err = 1;
    }
    if (!err) {
        /* Create EC group from DER encoding. */
        ret = wolfssl_ec_group_d2i(group, der->buffer, der->length);
        if (ret == NULL) {
            WOLFSSL_ERROR_MSG("Error loading DER buffer into WOLFSSL_EC_GROUP");
        }
    }

    /* Dispose of any allocated data. */
    FreeDer(&der);
    return ret;
}

#endif /* !NO_BIO */

#if defined(OPENSSL_ALL) && !defined(NO_CERTS)
/* Copy an EC group.
 *
 * Only used by wolfSSL_EC_KEY_dup at this time.
 *
 * @param [in, out] dst  Destination EC group.
 * @param [in]      src  Source EC group.
 * @return  0 on success.
 */
static int wolfssl_ec_group_copy(WOLFSSL_EC_GROUP* dst,
    const WOLFSSL_EC_GROUP* src)
{
    /* Copy the fields. */
    dst->curve_idx = src->curve_idx;
    dst->curve_nid = src->curve_nid;
    dst->curve_oid = src->curve_oid;

    return 0;
}
#endif /* OPENSSL_ALL && !NO_CERTS */

/* Copies ecc_key into new WOLFSSL_EC_GROUP object
 *
 * @param [in] src  EC group to duplicate.
 *
 * @return  EC group on success.
 * @return  NULL on error.
 */
WOLFSSL_EC_GROUP* wolfSSL_EC_GROUP_dup(const WOLFSSL_EC_GROUP *src)
{
    WOLFSSL_EC_GROUP* newGroup = NULL;

    if (src != NULL) {
        /* Create new group base on NID in original EC group. */
        newGroup = wolfSSL_EC_GROUP_new_by_curve_name(src->curve_nid);
     }

    return newGroup;
}

/* Compare two EC groups.
 *
 * Return code compliant with OpenSSL.
 *
 * @param [in] a    First EC group.
 * @param [in] b    Second EC group.
 * @param [in] ctx  Big number context to use when comparing fields. Unused.
 *
 * @return  0 if equal.
 * @return  1 if not equal.
 * @return  -1 on error.
 */
int wolfSSL_EC_GROUP_cmp(const WOLFSSL_EC_GROUP *a, const WOLFSSL_EC_GROUP *b,
                         WOLFSSL_BN_CTX *ctx)
{
    int ret;

    /* No BN operations performed. */
    (void)ctx;

    WOLFSSL_ENTER("wolfSSL_EC_GROUP_cmp");

    /* Validate parameters. */
    if ((a == NULL) || (b == NULL)) {
        WOLFSSL_MSG("wolfSSL_EC_GROUP_cmp Bad arguments");
        /* Return error value. */
        ret = -1;
    }
    /* Compare NID and wolfSSL curve index. */
    else {
        /* 0 when same, 1 when not. */
        ret = ((a->curve_nid == b->curve_nid) &&
               (a->curve_idx == b->curve_idx)) ? 0 : 1;
    }

    return ret;
}

#ifndef NO_WOLFSSL_STUB
/* Set the ASN.1 flag that indicate encoding of curve.
 *
 * Stub function - flag not used elsewhere.
 * Always encoded as named curve.
 *
 * @param [in] group  EC group to modify.
 * @param [in] flag   ASN.1 flag to set. Valid values:
 *                    OPENSSL_EC_EXPLICIT_CURVE, OPENSSL_EC_NAMED_CURVE
 */
void wolfSSL_EC_GROUP_set_asn1_flag(WOLFSSL_EC_GROUP *group, int flag)
{
    (void)group;
    (void)flag;

    WOLFSSL_ENTER("wolfSSL_EC_GROUP_set_asn1_flag");
    WOLFSSL_STUB("EC_GROUP_set_asn1_flag");
}
#endif

/* Get the curve NID of the group.
 *
 * Return code compliant with OpenSSL.
 *
 * @param [in] group  EC group.
 * @return  Curve NID on success.
 * @return  0 on error.
 */
int wolfSSL_EC_GROUP_get_curve_name(const WOLFSSL_EC_GROUP *group)
{
    int nid = 0;
    WOLFSSL_ENTER("wolfSSL_EC_GROUP_get_curve_name");

    if (group == NULL) {
        WOLFSSL_MSG("wolfSSL_EC_GROUP_get_curve_name Bad arguments");
    }
    else {
        nid = group->curve_nid;
    }

    return nid;
}

/* Get the degree (curve size in bits) of the EC group.
 *
 * Return code compliant with OpenSSL.
 *
 * @return  Degree of the curve on success.
 * @return  0 on error.
 */
int wolfSSL_EC_GROUP_get_degree(const WOLFSSL_EC_GROUP *group)
{
    int degree = 0;

    WOLFSSL_ENTER("wolfSSL_EC_GROUP_get_degree");

    if (group == NULL) {
        WOLFSSL_MSG("wolfSSL_EC_GROUP_get_degree Bad arguments");
    }
    else {
        switch (group->curve_nid) {
            case NID_secp112r1:
            case NID_secp112r2:
                degree = 112;
                break;
            case NID_secp128r1:
            case NID_secp128r2:
                degree = 128;
                break;
            case NID_secp160k1:
            case NID_secp160r1:
            case NID_secp160r2:
            case NID_brainpoolP160r1:
                degree = 160;
                break;
            case NID_secp192k1:
            case NID_brainpoolP192r1:
            case NID_X9_62_prime192v1:
            case NID_X9_62_prime192v2:
            case NID_X9_62_prime192v3:
                degree = 192;
                break;
            case NID_secp224k1:
            case NID_secp224r1:
            case NID_brainpoolP224r1:
                degree = 224;
                break;
            case NID_X9_62_prime239v1:
            case NID_X9_62_prime239v2:
            case NID_X9_62_prime239v3:
                degree = 239;
                break;
            case NID_secp256k1:
            case NID_brainpoolP256r1:
            case NID_X9_62_prime256v1:
                degree = 256;
                break;
            case NID_brainpoolP320r1:
                degree = 320;
                break;
            case NID_secp384r1:
            case NID_brainpoolP384r1:
                degree = 384;
                break;
            case NID_brainpoolP512r1:
                degree = 512;
                break;
            case NID_secp521r1:
                degree = 521;
                break;
        }
    }

    return degree;
}
#endif /* OPENSSL_EXTRA */

#if defined(OPENSSL_EXTRA) || defined(WOLFSSL_WPAS_SMALL)
/* Get the length of the order in bits of the EC group.
 *
 * TODO: consider switch statement or calculating directly from hex string
 * array instead of using mp_int.
 *
 * @param [in] group  EC group.
 * @return  Length of order in bits on success.
 * @return  0 on error.
 */
int wolfSSL_EC_GROUP_order_bits(const WOLFSSL_EC_GROUP *group)
{
    int ret = 0;
#ifdef WOLFSSL_SMALL_STACK
    mp_int *order = NULL;
#else
    mp_int order[1];
#endif

    /* Validate parameter. */
    if ((group == NULL) || (group->curve_idx < 0)) {
        WOLFSSL_MSG("wolfSSL_EC_GROUP_order_bits NULL error");
        ret = -1;
    }

#ifdef WOLFSSL_SMALL_STACK
    if (ret == 0) {
        /* Allocate memory for mp_int that will hold order value. */
        order = (mp_int *)XMALLOC(sizeof(*order), NULL,
            DYNAMIC_TYPE_TMP_BUFFER);
        if (order == NULL) {
            ret = -1;
        }
    }
#endif

    if (ret == 0) {
        /* Initialize mp_int. */
        ret = mp_init(order);
    }

    if (ret == 0) {
        /* Read hex string of order from wolfCrypt array of curves. */
        ret = mp_read_radix(order, ecc_sets[group->curve_idx].order,
            MP_RADIX_HEX);
        if (ret == 0) {
            /* Get bits of order. */
            ret = mp_count_bits(order);
        }
        /* Clear and free mp_int. */
        mp_clear(order);
    }

#ifdef WOLFSSL_SMALL_STACK
    /* Deallocate order. */
    XFREE(order, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif

    /* Convert error code to length of 0. */
    if (ret < 0) {
        ret = 0;
    }

    return ret;
}
#endif /* OPENSSL_EXTRA || WOLFSSL_WPAS_SMALL */

#if defined(OPENSSL_EXTRA)
/* Get the order of the group as a BN.
 *
 * Return code compliant with OpenSSL.
 *
 * @param [in]      group  EC group.
 * @param [in, out] order  BN to hold order value.
 * @param [in]      ctx    Context to use for BN operations. Unused.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_EC_GROUP_get_order(const WOLFSSL_EC_GROUP *group,
    WOLFSSL_BIGNUM *order, WOLFSSL_BN_CTX *ctx)
{
    int ret = 1;
    mp_int* mp = NULL;

    /* No BN operations performed - done with mp_int in BN. */
    (void)ctx;

    /* Validate parameters. */
    if ((group == NULL) || (order == NULL) || (order->internal == NULL)) {
        WOLFSSL_MSG("wolfSSL_EC_GROUP_get_order NULL error");
        ret = 0;
    }

    if (ret == 1) {
        mp = (mp_int*)order->internal;
    }
    /* Initialize */
    if ((ret == 1) && (mp_init(mp) != MP_OKAY)) {
        WOLFSSL_MSG("wolfSSL_EC_GROUP_get_order mp_init failure");
        ret = 0;
    }
    /* Read hex string of order from wolfCrypt array of curves. */
    if ((ret == 1) && (mp_read_radix(mp, ecc_sets[group->curve_idx].order,
            MP_RADIX_HEX) != MP_OKAY)) {
        WOLFSSL_MSG("wolfSSL_EC_GROUP_get_order mp_read order failure");
        /* Zero out any partial value but don't free. */
        mp_zero(mp);
        ret = 0;
    }

    return ret;
}

#endif /* OPENSSL_EXTRA */

/* End EC_GROUP */

/* Start EC_POINT */

#if defined(OPENSSL_EXTRA)

/* Set data of EC point into internal, wolfCrypt EC point object.
 *
 * EC_POINT Openssl -> WolfSSL
 *
 * @param [in, out] p  EC point to update.
 * @return  1 on success.
 * @return  -1 on failure.
 */
static int ec_point_internal_set(WOLFSSL_EC_POINT *p)
{
    int ret = 1;

    WOLFSSL_ENTER("ec_point_internal_set");

    /* Validate parameter. */
    if ((p == NULL) || (p->internal == NULL)) {
        WOLFSSL_MSG("ECPoint NULL error");
        ret = -1;
    }
    else {
        /* Get internal point as a wolfCrypt EC point. */
        ecc_point* point = (ecc_point*)p->internal;

        /* Set X ordinate if available. */
        if ((p->X != NULL) && (wolfssl_bn_get_value(p->X, point->x) != 1)) {
            WOLFSSL_MSG("ecc point X error");
            ret = -1;
        }
        /* Set Y ordinate if available. */
        if ((ret == 1) && (p->Y != NULL) && (wolfssl_bn_get_value(p->Y,
                point->y) != 1)) {
            WOLFSSL_MSG("ecc point Y error");
            ret = -1;
        }
        /* Set Z ordinate if available. */
        if ((ret == 1) && (p->Z != NULL) && (wolfssl_bn_get_value(p->Z,
                point->z) != 1)) {
            WOLFSSL_MSG("ecc point Z error");
            ret = -1;
        }
        /* Internal values set when operations succeeded. */
        p->inSet = (ret == 1);
    }

    return ret;
}

/* Set data of internal, wolfCrypt EC point object into EC point.
 *
 * EC_POINT WolfSSL -> OpenSSL
 *
 * @param [in, out] p  EC point to update.
 * @return  1 on success.
 * @return  -1 on failure.
 */
static int ec_point_external_set(WOLFSSL_EC_POINT *p)
{
    int ret = 1;

    WOLFSSL_ENTER("ec_point_external_set");

    /* Validate parameter. */
    if ((p == NULL) || (p->internal == NULL)) {
        WOLFSSL_MSG("ECPoint NULL error");
        ret = -1;
    }
    else {
        /* Get internal point as a wolfCrypt EC point. */
        ecc_point* point = (ecc_point*)p->internal;

        /* Set X ordinate. */
        if (wolfssl_bn_set_value(&p->X, point->x) != 1) {
            WOLFSSL_MSG("ecc point X error");
            ret = -1;
        }
        /* Set Y ordinate. */
        if ((ret == 1) && (wolfssl_bn_set_value(&p->Y, point->y) != 1)) {
            WOLFSSL_MSG("ecc point Y error");
            ret = -1;
        }
        /* Set Z ordinate. */
        if ((ret == 1) && (wolfssl_bn_set_value(&p->Z, point->z) != 1)) {
            WOLFSSL_MSG("ecc point Z error");
            ret = -1;
        }
        /* External values set when operations succeeded. */
        p->exSet = (ret == 1);
    }

    return ret;
}

/* Setup internals of EC point.
 *
 * Assumes point is not NULL.
 *
 * @param [in, out] point  EC point to update.
 * @return  1 on success.
 * @return  0 on failure.
 */
static int ec_point_setup(const WOLFSSL_EC_POINT *point) {
    int ret = 1;

    /* Check if internal values need setting. */
    if (!point->inSet) {
        WOLFSSL_MSG("No ECPoint internal set, do it");

        /* Forcing to non-constant type to update internals. */
        if (ec_point_internal_set((WOLFSSL_EC_POINT *)point) != 1) {
            WOLFSSL_MSG("ec_point_internal_set failed");
            ret = 0;
        }
    }

    return ret;
}

/* Create a new EC point from the group.
 *
 * @param [in] group  EC group.
 * @return  EC point on success.
 * @return  NULL on error.
 */
WOLFSSL_EC_POINT* wolfSSL_EC_POINT_new(const WOLFSSL_EC_GROUP* group)
{
    int err = 0;
    WOLFSSL_EC_POINT* point = NULL;

    WOLFSSL_ENTER("wolfSSL_EC_POINT_new");

    /* Validate parameter. */
    if (group == NULL) {
        WOLFSSL_MSG("wolfSSL_EC_POINT_new NULL error");
        err = 1;
    }

    if (!err) {
        /* Allocate memory for new EC point. */
        point = (WOLFSSL_EC_POINT*)XMALLOC(sizeof(WOLFSSL_EC_POINT), NULL,
            DYNAMIC_TYPE_ECC);
        if (point == NULL) {
            WOLFSSL_MSG("wolfSSL_EC_POINT_new malloc ecc point failure");
            err = 1;
        }
    }
    if (!err) {
        /* Clear fields of EC point. */
        XMEMSET(point, 0, sizeof(WOLFSSL_EC_POINT));

        /* Allocate internal EC point. */
        point->internal = wc_ecc_new_point();
        if (point->internal == NULL) {
            WOLFSSL_MSG("ecc_new_point failure");
            err = 1;
        }
    }

    if (err) {
        XFREE(point, NULL, DYNAMIC_TYPE_ECC);
        point = NULL;
    }
    return point;
}

#endif /* OPENSSL_EXTRA */

#if defined(OPENSSL_EXTRA) || defined(OPENSSL_EXTRA_X509_SMALL)
/* Dispose of the EC point.
 *
 * Cannot use point after this call.
 *
 * @param [in, out] point  EC point to free.
 */
void wolfSSL_EC_POINT_free(WOLFSSL_EC_POINT *point)
{
    WOLFSSL_ENTER("wolfSSL_EC_POINT_free");

    if (point != NULL) {
        if (point->internal != NULL) {
            wc_ecc_del_point((ecc_point*)point->internal);
            point->internal = NULL;
        }

        /* Free ordinates. */
        wolfSSL_BN_free(point->X);
        wolfSSL_BN_free(point->Y);
        wolfSSL_BN_free(point->Z);
        /* Clear fields. */
        point->X = NULL;
        point->Y = NULL;
        point->Z = NULL;
        point->inSet = 0;
        point->exSet = 0;

        /* Dispose of EC point. */
        XFREE(point, NULL, DYNAMIC_TYPE_ECC);
    }
}
#endif /* OPENSSL_EXTRA || OPENSSL_EXTRA_X509_SMALL */

#ifdef OPENSSL_EXTRA

/* Clear and dispose of the EC point.
 *
 * Cannot use point after this call.
 *
 * @param [in, out] point  EC point to free.
 */
void wolfSSL_EC_POINT_clear_free(WOLFSSL_EC_POINT *point)
{
    WOLFSSL_ENTER("wolfSSL_EC_POINT_clear_free");

    if (point != NULL) {
        if (point->internal != NULL) {
            /* Force internal point to be zeros. */
    #if !defined(HAVE_SELFTEST) && (!defined(HAVE_FIPS) || FIPS_VERSION_GT(2,0))
            wc_ecc_forcezero_point((ecc_point*)point->internal);
    #else
            ecc_point* p = (ecc_point*)point->internal;
            mp_forcezero(p->x);
            mp_forcezero(p->y);
            mp_forcezero(p->z);
    #endif
            wc_ecc_del_point((ecc_point*)point->internal);
            point->internal = NULL;
        }

        /* Clear the ordinates before freeing. */
        wolfSSL_BN_clear_free(point->X);
        wolfSSL_BN_clear_free(point->Y);
        wolfSSL_BN_clear_free(point->Z);
        /* Clear fields. */
        point->X = NULL;
        point->Y = NULL;
        point->Z = NULL;
        point->inSet = 0;
        point->exSet = 0;

        /* Dispose of EC point. */
        XFREE(point, NULL, DYNAMIC_TYPE_ECC);
    }
}

/* Print out the internals of EC point in debug and when logging callback set.
 *
 * Not an OpenSSL API.
 *
 * TODO: Use WOLFSSL_MSG_EX()?
 *
 * @param [in] msg    Message to prepend.
 * @param [in] point  EC point to print.
 */
void wolfSSL_EC_POINT_dump(const char *msg, const WOLFSSL_EC_POINT *point)
{
#if defined(DEBUG_WOLFSSL)
    char *num;

    WOLFSSL_ENTER("wolfSSL_EC_POINT_dump");

    /* Only print when debugging on. */
    if (WOLFSSL_IS_DEBUG_ON()) {
        if (point == NULL) {
            /* No point passed in so just put out "NULL". */
            WOLFSSL_MSG_EX("%s = NULL\n", msg);
        }
        else {
            /* Put out message and status of internal/external data set. */
            WOLFSSL_MSG_EX("%s:\n\tinSet=%d, exSet=%d\n", msg, point->inSet,
                point->exSet);
            /* Get x-ordinate as a hex string and print. */
            num = wolfSSL_BN_bn2hex(point->X);
            WOLFSSL_MSG_EX("\tX = %s\n", num);
            XFREE(num, NULL, DYNAMIC_TYPE_OPENSSL);
            /* Get x-ordinate as a hex string and print. */
            num = wolfSSL_BN_bn2hex(point->Y);
            WOLFSSL_MSG_EX("\tY = %s\n", num);
            XFREE(num, NULL, DYNAMIC_TYPE_OPENSSL);
            /* Get z-ordinate as a hex string and print. */
            num = wolfSSL_BN_bn2hex(point->Z);
            WOLFSSL_MSG_EX("\tZ = %s\n", num);
            XFREE(num, NULL, DYNAMIC_TYPE_OPENSSL);
        }
    }
#else
    (void)msg;
    (void)point;
#endif
}

/* Convert EC point to hex string that as either uncompressed or compressed.
 *
 * ECC point compression types were not included in selftest ecc.h
 *
 * @param [in] group  EC group for point.
 * @param [in] point  EC point to encode.
 * @param [in] form   Format of encoding. Valid values:
 *                    POINT_CONVERSION_UNCOMPRESSED, POINT_CONVERSION_COMPRESSED
 * @param [in] ctx    Context to use for BN operations. Unused.
 * @return  Allocated hex string on success.
 * @return  NULL on error.
 */
char* wolfSSL_EC_POINT_point2hex(const WOLFSSL_EC_GROUP* group,
    const WOLFSSL_EC_POINT* point, int form, WOLFSSL_BN_CTX* ctx)
{
    static const char* hexDigit = "0123456789ABCDEF";
    char* hex = NULL;
    int i;
    int sz = 0;
    int len = 0;
    int err = 0;

    /* No BN operations performed. */
    (void)ctx;

    /* Validate parameters. */
    if ((group == NULL) || (point == NULL)) {
        err = 1;
    }
    /* Get curve id expects a positive index. */
    if ((!err) && (group->curve_idx < 0)) {
        err = 1;
    }

    if (!err) {
        /* Get curve id to look up ordinate size. */
        int id = wc_ecc_get_curve_id(group->curve_idx);
        /* Get size of ordinate. */
        if ((sz = wc_ecc_get_curve_size_from_id(id)) < 0) {
            err = 1;
        }
    }
    if (!err) {
        /* <format byte> <x-ordinate> [<y-ordinate>] */
        len = sz + 1;
        if (form == POINT_CONVERSION_UNCOMPRESSED) {
            /* Include y ordinate when uncompressed. */
            len += sz;
        }

        /* Hex string: allocate 2 bytes to represent each byte plus 1 for '\0'.
         */
        hex = (char*)XMALLOC((size_t)(2 * len + 1), NULL, DYNAMIC_TYPE_ECC);
        if (hex == NULL) {
            err = 1;
        }
    }
    if (!err) {
        /* Make bytes all zeros to allow for ordinate values less than max size.
         */
        XMEMSET(hex, 0, (size_t)(2 * len + 1));

        /* Calculate offset as leading zeros not encoded. */
        i = sz - mp_unsigned_bin_size((mp_int*)point->X->internal) + 1;
        /* Put in x-ordinate after format byte. */
        if (mp_to_unsigned_bin((mp_int*)point->X->internal, (byte*)(hex + i)) <
                0) {
            err = 1;
        }
    }
    if (!err) {
        if (form == POINT_CONVERSION_COMPRESSED) {
            /* Compressed format byte value dependent on whether y-ordinate is
             * odd.
             */
            hex[0] = mp_isodd((mp_int*)point->Y->internal) ?
                ECC_POINT_COMP_ODD : ECC_POINT_COMP_EVEN;
            /* No y-ordinate. */
        }
        else {
            /* Put in uncompressed format byte. */
            hex[0] = ECC_POINT_UNCOMP;
            /* Calculate offset as leading zeros not encoded. */
            i = 1 + 2 * sz - mp_unsigned_bin_size((mp_int*)point->Y->internal);
            /* Put in y-ordinate after x-ordinate. */
            if (mp_to_unsigned_bin((mp_int*)point->Y->internal,
                    (byte*)(hex + i)) < 0) {
                err = 1;
            }
        }
    }
    if (!err) {
        /* Convert binary encoding to hex string. */
        /* Start at end so as not to overwrite. */
        for (i = len-1; i >= 0; i--) {
            /* Get byte value and store has hex string. */
            byte b = (byte)hex[i];
            hex[i * 2 + 1] = hexDigit[b  & 0xf];
            hex[i * 2    ] = hexDigit[b >>   4];
        }
        /* Memset put trailing zero or '\0' on end of string. */
    }

    if (err && (hex != NULL)) {
        /* Dispose of allocated data not being returned. */
        XFREE(hex,  NULL, DYNAMIC_TYPE_ECC);
        hex = NULL;
    }
    /* Return hex string encoding. */
    return hex;
}

static size_t hex_to_bytes(const char *hex, unsigned char *output, size_t sz)
{
    word32 i;
    for (i = 0; i < sz; i++) {
        signed char ch1, ch2;
        ch1 = HexCharToByte(hex[i * 2]);
        ch2 = HexCharToByte(hex[i * 2 + 1]);
        if ((ch1 < 0) || (ch2 < 0)) {
            WOLFSSL_MSG("hex_to_bytes: syntax error");
            return 0;
        }
        output[i] = (unsigned char)((ch1 << 4) + ch2);
    }
    return sz;
}

WOLFSSL_EC_POINT* wolfSSL_EC_POINT_hex2point(const EC_GROUP *group,
            const char *hex, WOLFSSL_EC_POINT*p, WOLFSSL_BN_CTX *ctx)
{
    /* for uncompressed mode */
    size_t str_sz;
    BIGNUM *Gx  = NULL;
    BIGNUM *Gy  = NULL;
    char   strGx[MAX_ECC_BYTES * 2 + 1];

    /* for compressed mode */
    int    key_sz;
    byte   *octGx = (byte *)strGx; /* octGx[MAX_ECC_BYTES] */

    int p_alloc = 0;
    int ret;

    WOLFSSL_ENTER("wolfSSL_EC_POINT_hex2point");

    if (group == NULL || hex == NULL || ctx == NULL)
        return NULL;

    if (p == NULL) {
        if ((p = wolfSSL_EC_POINT_new(group)) == NULL) {
            WOLFSSL_MSG("wolfSSL_EC_POINT_new");
            goto err;
        }
        p_alloc = 1;
    }

    key_sz = (wolfSSL_EC_GROUP_get_degree(group) + 7) / 8;
    if (hex[0] ==  '0' && hex[1] == '4') { /* uncompressed mode */
        str_sz = key_sz * 2;

        XMEMSET(strGx, 0x0, str_sz + 1);
        XMEMCPY(strGx, hex + 2, str_sz);

        if (wolfSSL_BN_hex2bn(&Gx, strGx) == 0)
            goto err;

        if (wolfSSL_BN_hex2bn(&Gy, hex + 2 + str_sz) == 0)
            goto err;

        ret = wolfSSL_EC_POINT_set_affine_coordinates_GFp
                                            (group, p, Gx, Gy, ctx);

        if (ret != WOLFSSL_SUCCESS) {
            WOLFSSL_MSG("wolfSSL_EC_POINT_set_affine_coordinates_GFp");
            goto err;
        }
    }
    else if (hex[0] == '0' && (hex[1] == '2' || hex[1] == '3')) {
        size_t sz = XSTRLEN(hex + 2) / 2;
        /* compressed mode */
        octGx[0] = ECC_POINT_COMP_ODD;
        if (hex_to_bytes(hex + 2, octGx + 1, sz) != sz) {
            goto err;
        }
        if (wolfSSL_ECPoint_d2i(octGx, key_sz + 1, group, p)
                                            != WOLFSSL_SUCCESS) {
            goto err;
        }
    }
    else
        goto err;

    wolfSSL_BN_free(Gx);
    wolfSSL_BN_free(Gy);
    return p;

err:
    wolfSSL_BN_free(Gx);
    wolfSSL_BN_free(Gy);
    if (p_alloc) {
        EC_POINT_free(p);
    }
    return NULL;

}

/* Encode the EC point as an uncompressed point in DER.
 *
 * Return code compliant with OpenSSL.
 * Not OpenSSL API.
 *
 * @param [in]      group  EC group point belongs to.
 * @param [in]      point  EC point to encode.
 * @param [out]     out    Buffer to encode into. May be NULL.
 * @param [in, out] len    On in, length of buffer in bytes.
 *                         On out, length of encoding in bytes.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_ECPoint_i2d(const WOLFSSL_EC_GROUP *group,
    const WOLFSSL_EC_POINT *point, unsigned char *out, unsigned int *len)
{
    int res = 1;

    WOLFSSL_ENTER("wolfSSL_ECPoint_i2d");

    /* Validate parameters. */
    if ((group == NULL) || (point == NULL) || (len == NULL)) {
        WOLFSSL_MSG("wolfSSL_ECPoint_i2d NULL error");
        res = 0;
    }

    /* Ensure points internals are set up. */
    if ((res == 1) && (ec_point_setup(point) != 1)) {
        res = 0;
    }

    /* Dump the point if encoding. */
    if ((res == 1) && (out != NULL)) {
        wolfSSL_EC_POINT_dump("i2d p", point);
    }

    if (res == 1) {
        /* DER encode point in uncompressed format. */
        int ret = wc_ecc_export_point_der(group->curve_idx,
            (ecc_point*)point->internal, out, len);
        /* Check return. When out is NULL, return will be length only error. */
        if ((ret != MP_OKAY) && ((out != NULL) ||
                                 (ret != WC_NO_ERR_TRACE(LENGTH_ONLY_E)))) {
            WOLFSSL_MSG("wolfSSL_ECPoint_i2d wc_ecc_export_point_der failed");
            res = 0;
        }
    }

    return res;
}

/* Decode the uncompressed point in DER into EC point.
 *
 * Return code compliant with OpenSSL.
 * Not OpenSSL API.
 *
 * @param [in]      in     Buffer containing DER encoded point.
 * @param [in]      len    Length of data in bytes.
 * @param [in]      group  EC group associated with point.
 * @param [in, out] point  EC point to set data into.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_ECPoint_d2i(const unsigned char *in, unsigned int len,
    const WOLFSSL_EC_GROUP *group, WOLFSSL_EC_POINT *point)
{
    int ret = 1;
    WOLFSSL_BIGNUM* x = NULL;
    WOLFSSL_BIGNUM* y = NULL;

    WOLFSSL_ENTER("wolfSSL_ECPoint_d2i");

    /* Validate parameters. */
    if ((in == NULL) || (group == NULL) || (point == NULL) ||
            (point->internal == NULL)) {
        WOLFSSL_MSG("wolfSSL_ECPoint_d2i NULL error");
        ret = 0;
    }

    if (ret == 1) {
    #if !defined(HAVE_SELFTEST) && (!defined(HAVE_FIPS) || FIPS_VERSION_GT(2,0))
        /* Import point into internal EC point. */
        if (wc_ecc_import_point_der_ex(in, len, group->curve_idx,
                (ecc_point*)point->internal, 0) != MP_OKAY) {
            WOLFSSL_MSG("wc_ecc_import_point_der_ex failed");
            ret = 0;
        }
    #else
        /* ECC_POINT_UNCOMP is not defined CAVP self test so use magic number */
        if (in[0] == 0x04) {
            /* Import point into internal EC point. */
            if (wc_ecc_import_point_der((unsigned char *)in, len,
                    group->curve_idx, (ecc_point*)point->internal) != MP_OKAY) {
                WOLFSSL_MSG("wc_ecc_import_point_der failed");
                ret = 0;
            }
        }
        else {
            WOLFSSL_MSG("Only uncompressed points supported with "
                        "HAVE_SELFTEST");
            ret = 0;
        }
    #endif
    }

    if (ret == 1)
        point->inSet = 1;

    /* Set new external point. */
    if (ret == 1 && ec_point_external_set(point) != 1) {
        WOLFSSL_MSG("ec_point_external_set failed");
        ret = 0;
    }

    if (ret == 1 && !wolfSSL_BN_is_one(point->Z)) {
#if !defined(WOLFSSL_SP_MATH) && !defined(WOLF_CRYPTO_CB_ONLY_ECC)
        x = wolfSSL_BN_new();
        y = wolfSSL_BN_new();
        if (x == NULL || y == NULL)
            ret = 0;

        if (ret == 1 && wolfSSL_EC_POINT_get_affine_coordinates_GFp(group,
                point, x, y, NULL) != 1) {
            WOLFSSL_MSG("wolfSSL_EC_POINT_get_affine_coordinates_GFp failed");
            ret = 0;
        }

        /* wolfSSL_EC_POINT_set_affine_coordinates_GFp check that the point is
         * on the curve. */
        if (ret == 1 && wolfSSL_EC_POINT_set_affine_coordinates_GFp(group,
                point, x, y, NULL) != 1) {
            WOLFSSL_MSG("wolfSSL_EC_POINT_set_affine_coordinates_GFp failed");
            ret = 0;
        }
#else
        WOLFSSL_MSG("Importing non-affine point. This may cause issues in math "
                    "operations later on.");
#endif
    }

    if (ret == 1) {
        /* Dump new point. */
        wolfSSL_EC_POINT_dump("d2i p", point);
    }

    wolfSSL_BN_free(x);
    wolfSSL_BN_free(y);

    return ret;
}

/* Encode point as octet string.
 *
 * HYBRID not supported.
 *
 * @param [in]  group  EC group that point belongs to.
 * @param [in]  point  EC point to encode.
 * @param [in]  form   Format of encoding. Valid values:
 *                     POINT_CONVERSION_UNCOMPRESSED,POINT_CONVERSION_COMPRESSED
 * @param [out] buf    Buffer to write encoding into.
 * @param [in]  len    Length of buffer.
 * @param [in]  ctx    Context to use for BN operations. Unused.
 * @return  Length of encoded data on success.
 * @return  0 on error.
 */
size_t wolfSSL_EC_POINT_point2oct(const WOLFSSL_EC_GROUP *group,
   const WOLFSSL_EC_POINT *point, int form, byte *buf, size_t len,
   WOLFSSL_BN_CTX *ctx)
{
    int err = 0;
    word32 enc_len = (word32)len;
#if !defined(HAVE_SELFTEST) && (!defined(HAVE_FIPS) || FIPS_VERSION_GT(2,0))
    int compressed = ((form == POINT_CONVERSION_COMPRESSED) ? 1 : 0);
#endif /* !HAVE_SELFTEST */

    WOLFSSL_ENTER("wolfSSL_EC_POINT_point2oct");

    /* No BN operations performed. */
    (void)ctx;

    /* Validate parameters. */
    if ((group == NULL) || (point == NULL)) {
        err = 1;
    }

    /* Ensure points internals are set up. */
    if ((!err) && (ec_point_setup(point) != 1)) {
        err = 1;
    }

    /* Special case when point is infinity. */
    if ((!err) && wolfSSL_EC_POINT_is_at_infinity(group, point)) {
        /* Encoding is a single octet: 0x00. */
        enc_len = 1;
        if (buf != NULL) {
            /* Check whether buffer has space. */
            if (len < 1) {
                ECerr(EC_F_EC_GFP_SIMPLE_POINT2OCT, EC_R_BUFFER_TOO_SMALL);
                err = 1;
            }
            else {
                /* Put in encoding of infinity. */
                buf[0] = 0x00;
            }
        }
    }
    /* Not infinity. */
    else if (!err) {
        /* Validate format. */
        if (form != POINT_CONVERSION_UNCOMPRESSED
        #ifndef HAVE_SELFTEST
                && form != POINT_CONVERSION_COMPRESSED
        #endif /* !HAVE_SELFTEST */
            ) {
            WOLFSSL_MSG("Unsupported point form");
            err = 1;
        }

        if (!err) {
            int ret;

    #if !defined(HAVE_SELFTEST) && (!defined(HAVE_FIPS) || FIPS_VERSION_GT(2,0))
            /* Encode as compressed or uncompressed. */
            ret = wc_ecc_export_point_der_ex(group->curve_idx,
                (ecc_point*)point->internal, buf, &enc_len, compressed);
    #else
            /* Encode uncompressed point in DER format. */
            ret = wc_ecc_export_point_der(group->curve_idx,
                (ecc_point*)point->internal, buf, &enc_len);
    #endif /* !HAVE_SELFTEST */
            /* Check return. When buf is NULL, return will be length only
             * error.
             */
            if (ret != ((buf != NULL) ? MP_OKAY : LENGTH_ONLY_E)) {
                err = 1;
            }
        }
    }

#if defined(DEBUG_WOLFSSL)
    if (!err) {
        wolfSSL_EC_POINT_dump("wolfSSL_EC_POINT_point2oct point", point);
        WOLFSSL_MSG("\twolfSSL_EC_POINT_point2oct output:");
        WOLFSSL_BUFFER(buf, enc_len);
    }
#endif

    /* On error, return encoding length of 0. */
    if (err) {
        enc_len = 0;
    }
    return (size_t)enc_len;
}


/* Convert octet string to EC point.
 *
 * @param [in]      group  EC group.
 * @param [in, out] point  EC point to set data into.
 * @param [in]      buf    Buffer holding octet string.
 * @param [in]      len    Length of data in buffer in bytes.
 * @param [in]      ctx    Context to use for BN operations. Unused.
 */
int wolfSSL_EC_POINT_oct2point(const WOLFSSL_EC_GROUP *group,
    WOLFSSL_EC_POINT *point, const unsigned char *buf, size_t len,
    WOLFSSL_BN_CTX *ctx)
{
    int ret;

    WOLFSSL_ENTER("wolfSSL_EC_POINT_oct2point");

    /* No BN operations performed. */
    (void)ctx;

    /* Validate parameters. */
    if ((group == NULL) || (point == NULL)) {
        ret = 0;
    }
    else {
        /* Decode DER encoding into EC point. */
        ret = wolfSSL_ECPoint_d2i((unsigned char*)buf, (unsigned int)len, group,
            point);
    }

    return ret;
}

/* Convert an EC point to a single BN.
 *
 * @param [in]      group  EC group.
 * @param [in]      point  EC point.
 * @param [in]      form   Format of encoding. Valid values:
 *                         POINT_CONVERSION_UNCOMPRESSED,
 *                         POINT_CONVERSION_COMPRESSED.
 * @param [in, out] bn     BN to hold point value.
 *                         When NULL a new BN is allocated otherwise this is
 *                         returned on success.
 * @param [in]      ctx    Context to use for BN operations. Unused.
 * @return  BN object with point as a value on success.
 * @return  NULL on error.
 */
WOLFSSL_BIGNUM *wolfSSL_EC_POINT_point2bn(const WOLFSSL_EC_GROUP* group,
    const WOLFSSL_EC_POINT* point, int form, WOLFSSL_BIGNUM* bn,
    WOLFSSL_BN_CTX* ctx)
{
    int err = 0;
    size_t len = 0;
    byte *buf = NULL;
    WOLFSSL_BIGNUM *ret = NULL;

    WOLFSSL_ENTER("wolfSSL_EC_POINT_oct2point");

    /* Validate parameters. */
    if ((group == NULL) || (point == NULL)) {
        err = 1;
    }

    /* Calculate length of octet encoding. */
    if ((!err) && ((len = wolfSSL_EC_POINT_point2oct(group, point, form, NULL,
            0, ctx)) == 0)) {
        err = 1;
    }
    /* Allocate buffer to hold octet encoding. */
    if ((!err) && ((buf = (byte*)XMALLOC(len, NULL, DYNAMIC_TYPE_TMP_BUFFER)) ==
            NULL)) {
        WOLFSSL_MSG("malloc failed");
        err = 1;
    }
    /* Encode EC point as an octet string. */
    if ((!err) && (wolfSSL_EC_POINT_point2oct(group, point, form, buf, len,
            ctx) != len)) {
        err = 1;
    }
    /* Load BN with octet string data. */
    if (!err) {
        ret = wolfSSL_BN_bin2bn(buf, (int)len, bn);
    }

    /* Dispose of any allocated data. */
    XFREE(buf, NULL, DYNAMIC_TYPE_TMP_BUFFER);

    return ret;
}

#if defined(USE_ECC_B_PARAM) && !defined(HAVE_SELFTEST) && \
    (!defined(HAVE_FIPS) || FIPS_VERSION_GT(2,0))
/* Check if EC point is on the the curve defined by the EC group.
 *
 * @param [in] group  EC group defining curve.
 * @param [in] point  EC point to check.
 * @param [in] ctx    Context to use for BN operations. Unused.
 * @return  1 when point is on curve.
 * @return  0 when point is not on curve or error.
 */
int wolfSSL_EC_POINT_is_on_curve(const WOLFSSL_EC_GROUP *group,
    const WOLFSSL_EC_POINT *point, WOLFSSL_BN_CTX *ctx)
{
    int err = 0;

    WOLFSSL_ENTER("wolfSSL_EC_POINT_is_on_curve");

    /* No BN operations performed. */
    (void)ctx;

    /* Validate parameters. */
    if ((group == NULL) || (point == NULL)) {
        WOLFSSL_MSG("Invalid arguments");
        err = 1;
    }

    /* Ensure internal EC point set. */
    if ((!err) && (!point->inSet) && ec_point_internal_set(
            (WOLFSSL_EC_POINT*)point) != 1) {
        WOLFSSL_MSG("ec_point_internal_set error");
        err = 1;
    }

    /* Check point is on curve from group. */
    if ((!err) && (wc_ecc_point_is_on_curve((ecc_point*)point->internal,
            group->curve_idx) != MP_OKAY)) {
        err = 1;
    }

    /* Return boolean of on curve. No error means on curve. */
    return !err;
}
#endif /* USE_ECC_B_PARAM && !HAVE_SELFTEST && !(FIPS_VERSION <= 2) */

#if !defined(WOLFSSL_SP_MATH) && !defined(WOLF_CRYPTO_CB_ONLY_ECC)
/* Convert Jacobian ordinates to affine.
 *
 * @param [in]      group  EC group.
 * @param [in]      point  EC point to get coordinates from.
 * @return  1 on success.
 * @return  0 on error.
 */
int ec_point_convert_to_affine(const WOLFSSL_EC_GROUP *group,
    WOLFSSL_EC_POINT *point)
{
    int err = 0;
    mp_digit mp = 0;
#ifdef WOLFSSL_SMALL_STACK
    mp_int* modulus;
#else
    mp_int modulus[1];
#endif

#ifdef WOLFSSL_SMALL_STACK
    /* Allocate memory for curve's prime modulus. */
    modulus = (mp_int*)XMALLOC(sizeof(mp_int), NULL, DYNAMIC_TYPE_BIGINT);
    if (modulus == NULL) {
        err = 1;
    }
#endif
    /* Initialize the MP integer. */
    if ((!err) && (mp_init(modulus) != MP_OKAY)) {
        WOLFSSL_MSG("mp_init failed");
        err = 1;
    }

    if (!err) {
        /* Get the modulus from the hex string in the EC curve set. */
        if (mp_read_radix(modulus, ecc_sets[group->curve_idx].prime,
                MP_RADIX_HEX) != MP_OKAY) {
            WOLFSSL_MSG("mp_read_radix failed");
            err = 1;
        }
        /* Get Montgomery multiplier for the modulus as ordinates in
         * Montgomery form.
         */
        if ((!err) && (mp_montgomery_setup(modulus, &mp) != MP_OKAY)) {
            WOLFSSL_MSG("mp_montgomery_setup failed");
            err = 1;
        }
        /* Map internal EC point from Jacobian to affine. */
        if ((!err) && (ecc_map((ecc_point*)point->internal, modulus, mp) !=
                MP_OKAY)) {
            WOLFSSL_MSG("ecc_map failed");
            err = 1;
        }
        /* Set new ordinates into external EC point. */
        if ((!err) && (ec_point_external_set((WOLFSSL_EC_POINT *)point) != 1)) {
            WOLFSSL_MSG("ec_point_external_set failed");
            err = 1;
        }

        point->exSet = !err;
        mp_clear(modulus);
    }

#ifdef WOLFSSL_SMALL_STACK
    XFREE(modulus, NULL, DYNAMIC_TYPE_BIGINT);
#endif

    return err;
}

/* Get the affine coordinates of the EC point on a Prime curve.
 *
 * When z-ordinate is not one then coordinates are Jacobian and need to be
 * converted to affine before storing in BNs.
 *
 * Return code compliant with OpenSSL.
 *
 * TODO: OpenSSL doesn't change point when Jacobian. Do the same?
 *
 * @param [in]      group  EC group.
 * @param [in]      point  EC point to get coordinates from.
 * @param [in, out] x      BN to hold x-ordinate.
 * @param [in, out] y      BN to hold y-ordinate.
 * @param [in]      ctx    Context to use for BN operations. Unused.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_EC_POINT_get_affine_coordinates_GFp(const WOLFSSL_EC_GROUP* group,
    const WOLFSSL_EC_POINT* point, WOLFSSL_BIGNUM* x, WOLFSSL_BIGNUM* y,
    WOLFSSL_BN_CTX* ctx)
{
    int ret = 1;

    /* BN operations don't need context. */
    (void)ctx;

    WOLFSSL_ENTER("wolfSSL_EC_POINT_get_affine_coordinates_GFp");

    /* Validate parameters. */
    if ((group == NULL) || (point == NULL) || (point->internal == NULL) ||
            (x == NULL) || (y == NULL)) {
        WOLFSSL_MSG("wolfSSL_EC_POINT_get_affine_coordinates_GFp NULL error");
        ret = 0;
    }
    /* Don't return point at infinity. */
    if ((ret == 1) && wolfSSL_EC_POINT_is_at_infinity(group, point)) {
        ret = 0;
    }

    /* Ensure internal EC point has values of external EC point. */
    if ((ret == 1) && (ec_point_setup(point) != 1)) {
        ret = 0;
    }

    /* Check whether ordinates are in Jacobian form. */
    if ((ret == 1) && (!wolfSSL_BN_is_one(point->Z))) {
        /* Convert from Jacobian to affine. */
        if (ec_point_convert_to_affine(group, (WOLFSSL_EC_POINT*)point) == 1) {
            ret = 0;
        }
    }

    /* Copy the externally set x and y ordinates. */
    if ((ret == 1) && (BN_copy(x, point->X) == NULL)) {
        ret = 0;
    }
    if ((ret == 1) && (BN_copy(y, point->Y) == NULL)) {
        ret = 0;
    }

    return ret;
}
#endif /* !WOLFSSL_SP_MATH && !WOLF_CRYPTO_CB_ONLY_ECC */

/* Sets the affine coordinates that belong on a prime curve.
 *
 * @param [in]      group  EC group.
 * @param [in, out] point  EC point to set coordinates into.
 * @param [in]      x      BN holding x-ordinate.
 * @param [in]      y      BN holding y-ordinate.
 * @param [in]      ctx    Context to use for BN operations. Unused.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_EC_POINT_set_affine_coordinates_GFp(const WOLFSSL_EC_GROUP* group,
    WOLFSSL_EC_POINT* point, const WOLFSSL_BIGNUM* x, const WOLFSSL_BIGNUM* y,
    WOLFSSL_BN_CTX* ctx)
{
    int ret = 1;

    /* BN operations don't need context. */
    (void)ctx;

    WOLFSSL_ENTER("wolfSSL_EC_POINT_set_affine_coordinates_GFp");

    /* Validate parameters. */
    if ((group == NULL) || (point == NULL) || (point->internal == NULL) ||
            (x == NULL) || (y == NULL)) {
        WOLFSSL_MSG("wolfSSL_EC_POINT_set_affine_coordinates_GFp NULL error");
        ret = 0;
    }

    /* Ensure we have a object for x-ordinate. */
    if ((ret == 1) && (point->X == NULL) &&
            ((point->X = wolfSSL_BN_new()) == NULL)) {
        WOLFSSL_MSG("wolfSSL_BN_new failed");
        ret = 0;
    }
    /* Ensure we have a object for y-ordinate. */
    if ((ret == 1) && (point->Y == NULL) &&
            ((point->Y = wolfSSL_BN_new()) == NULL)) {
        WOLFSSL_MSG("wolfSSL_BN_new failed");
        ret = 0;
    }
    /* Ensure we have a object for z-ordinate. */
    if ((ret == 1) && (point->Z == NULL) &&
            ((point->Z = wolfSSL_BN_new()) == NULL)) {
        WOLFSSL_MSG("wolfSSL_BN_new failed");
        ret = 0;
    }

    /* Copy the x-ordinate. */
    if ((ret == 1) && ((wolfSSL_BN_copy(point->X, x)) == NULL)) {
        WOLFSSL_MSG("wolfSSL_BN_copy failed");
        ret = 0;
    }
    /* Copy the y-ordinate. */
    if ((ret == 1) && ((wolfSSL_BN_copy(point->Y, y)) == NULL)) {
        WOLFSSL_MSG("wolfSSL_BN_copy failed");
        ret = 0;
    }
    /* z-ordinate is one for affine coordinates. */
    if ((ret == 1) && ((wolfSSL_BN_one(point->Z)) == 0)) {
        WOLFSSL_MSG("wolfSSL_BN_one failed");
        ret = 0;
    }

    /* Copy the new point data to internal object. */
    if ((ret == 1) && (ec_point_internal_set((WOLFSSL_EC_POINT *)point) != 1)) {
        WOLFSSL_MSG("ec_point_internal_set failed");
        ret = 0;
    }

#if defined(USE_ECC_B_PARAM) && !defined(HAVE_SELFTEST) && \
    (!defined(HAVE_FIPS) || FIPS_VERSION_GT(2,0))
    /* Check that the point is valid. */
    if ((ret == 1) && (wolfSSL_EC_POINT_is_on_curve(group,
            (WOLFSSL_EC_POINT *)point, ctx) != 1)) {
        WOLFSSL_MSG("EC_POINT_is_on_curve failed");
        ret = 0;
    }
#endif

    return ret;
}

#if !defined(WOLFSSL_ATECC508A) && !defined(WOLFSSL_ATECC608A) && \
    !defined(HAVE_SELFTEST) && !defined(WOLFSSL_SP_MATH) && \
    !defined(WOLF_CRYPTO_CB_ONLY_ECC)
/* Add two points on the same together.
 *
 * @param [in]  curveIdx  Index of curve in ecc_set.
 * @param [out] r         Result point.
 * @param [in]  p1        First point to add.
 * @param [in]  p2        Second point to add.
 * @return  1 on success.
 * @return  0 on error.
 */
static int wolfssl_ec_point_add(int curveIdx, ecc_point* r, ecc_point* p1,
    ecc_point* p2)
{
    int ret = 1;
#ifdef WOLFSSL_SMALL_STACK
    mp_int* a = NULL;
    mp_int* prime = NULL;
    mp_int* mu = NULL;
#else
    mp_int a[1];
    mp_int prime[1];
    mp_int mu[1];
#endif
    mp_digit mp = 0;
    ecc_point* montP1 = NULL;
    ecc_point* montP2 = NULL;

#ifdef WOLFSSL_SMALL_STACK
    if (ret == 1) {
        /* Allocate memory for curve parameter: a. */
        a = (mp_int*)XMALLOC(sizeof(mp_int), NULL, DYNAMIC_TYPE_BIGINT);
        if (a == NULL) {
            WOLFSSL_MSG("Failed to allocate memory for mp_int a");
            ret = 0;
        }
    }
    if (ret == 1) {
        /* Allocate memory for curve parameter: prime. */
        prime = (mp_int*)XMALLOC(sizeof(mp_int), NULL, DYNAMIC_TYPE_BIGINT);
        if (prime == NULL) {
            WOLFSSL_MSG("Failed to allocate memory for mp_int prime");
            ret = 0;
        }
    }
    if (ret == 1) {
        /* Allocate memory for mu (Montgomery normalizer). */
        mu = (mp_int*)XMALLOC(sizeof(mp_int), NULL, DYNAMIC_TYPE_BIGINT);
        if (mu == NULL) {
            WOLFSSL_MSG("Failed to allocate memory for mp_int mu");
            ret = 0;
        }
    }
    if (ret == 1) {
        /* Zero out all MP int data in case initialization fails. */
        XMEMSET(a, 0, sizeof(mp_int));
        XMEMSET(prime, 0, sizeof(mp_int));
        XMEMSET(mu, 0, sizeof(mp_int));
    }
#endif

    /* Initialize the MP ints. */
    if ((ret == 1) && (mp_init_multi(prime, a, mu, NULL, NULL, NULL) !=
            MP_OKAY)) {
        WOLFSSL_MSG("mp_init_multi error");
        ret = 0;
    }

    /* Read the curve parameter: a. */
    if ((ret == 1) && (mp_read_radix(a, ecc_sets[curveIdx].Af, MP_RADIX_HEX) !=
            MP_OKAY)) {
        WOLFSSL_MSG("mp_read_radix a error");
        ret = 0;
    }

    /* Read the curve parameter: prime. */
    if ((ret == 1) && (mp_read_radix(prime, ecc_sets[curveIdx].prime,
            MP_RADIX_HEX) != MP_OKAY)) {
        WOLFSSL_MSG("mp_read_radix prime error");
        ret = 0;
    }

    /* Calculate the Montgomery product. */
    if ((ret == 1) && (mp_montgomery_setup(prime, &mp) != MP_OKAY)) {
        WOLFSSL_MSG("mp_montgomery_setup nqm error");
        ret = 0;
    }

    /* TODO: use the heap filed of one of the points? */
    /* Allocate new points to hold the Montgomery form values. */
    if ((ret == 1) && (((montP1 = wc_ecc_new_point_h(NULL)) == NULL) ||
            ((montP2 = wc_ecc_new_point_h(NULL)) == NULL))) {
        WOLFSSL_MSG("wc_ecc_new_point_h nqm error");
        ret = 0;
    }

    /* Calculate the Montgomery normalizer. */
    if ((ret == 1) && (mp_montgomery_calc_normalization(mu, prime) !=
            MP_OKAY)) {
        WOLFSSL_MSG("mp_montgomery_calc_normalization error");
        ret = 0;
    }

    /* Convert to Montgomery form. */
    if ((ret == 1) && (mp_cmp_d(mu, 1) == MP_EQ)) {
        /* Copy the points if the normalizer is 1.  */
        if ((wc_ecc_copy_point(p1, montP1) != MP_OKAY) ||
                (wc_ecc_copy_point(p2, montP2) != MP_OKAY)) {
            WOLFSSL_MSG("wc_ecc_copy_point error");
            ret = 0;
        }
    }
    else if (ret == 1) {
        /* Multiply each ordinate by the Montgomery normalizer.  */
        if ((mp_mulmod(p1->x, mu, prime, montP1->x) != MP_OKAY) ||
                (mp_mulmod(p1->y, mu, prime, montP1->y) != MP_OKAY) ||
                (mp_mulmod(p1->z, mu, prime, montP1->z) != MP_OKAY)) {
            WOLFSSL_MSG("mp_mulmod error");
            ret = 0;
        }
        /* Multiply each ordinate by the Montgomery normalizer.  */
        if ((mp_mulmod(p2->x, mu, prime, montP2->x) != MP_OKAY) ||
                (mp_mulmod(p2->y, mu, prime, montP2->y) != MP_OKAY) ||
                (mp_mulmod(p2->z, mu, prime, montP2->z) != MP_OKAY)) {
            WOLFSSL_MSG("mp_mulmod error");
            ret = 0;
        }
    }

    /* Perform point addition with internal EC point objects - Jacobian form
     * result.
     */
    if ((ret == 1) && (ecc_projective_add_point(montP1, montP2, r, a, prime,
            mp) != MP_OKAY)) {
        WOLFSSL_MSG("ecc_projective_add_point error");
        ret = 0;
    }

    /* Map point back to affine coordinates. Converts from Montogomery form. */
    if ((ret == 1) && (ecc_map(r, prime, mp) != MP_OKAY)) {
        WOLFSSL_MSG("ecc_map error");
        ret = 0;
    }

    /* Dispose of allocated memory. */
    mp_clear(a);
    mp_clear(prime);
    mp_clear(mu);
    wc_ecc_del_point_h(montP1, NULL);
    wc_ecc_del_point_h(montP2, NULL);
#ifdef WOLFSSL_SMALL_STACK
    XFREE(a, NULL, DYNAMIC_TYPE_BIGINT);
    XFREE(prime, NULL, DYNAMIC_TYPE_BIGINT);
    XFREE(mu, NULL, DYNAMIC_TYPE_BIGINT);
#endif
    return ret;
}

/* Add two points on the same curve together.
 *
 * @param [in]  group  EC group.
 * @param [out] r      EC point that is result of point addition.
 * @param [in]  p1     First EC point to add.
 * @param [in]  p2     Second EC point to add.
 * @param [in]  ctx    Context to use for BN operations. Unused.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_EC_POINT_add(const WOLFSSL_EC_GROUP* group, WOLFSSL_EC_POINT* r,
    const WOLFSSL_EC_POINT* p1, const WOLFSSL_EC_POINT* p2, WOLFSSL_BN_CTX* ctx)
{
    int ret = 1;

    /* No BN operations performed. */
    (void)ctx;

    /* Validate parameters. */
    if ((group == NULL) || (r == NULL) || (p1 == NULL) || (p2 == NULL)) {
        WOLFSSL_MSG("wolfSSL_EC_POINT_add error");
        ret = 0;
    }

    /* Ensure the internal objects of the EC points are setup. */
    if ((ret == 1) && ((ec_point_setup(r) != 1) || (ec_point_setup(p1) != 1) ||
            (ec_point_setup(p2) != 1))) {
        WOLFSSL_MSG("ec_point_setup error");
        ret = 0;
    }

#ifdef DEBUG_WOLFSSL
    if (ret == 1) {
        int nid = wolfSSL_EC_GROUP_get_curve_name(group);
        const char* curve = wolfSSL_OBJ_nid2ln(nid);
        const char* nistName = wolfSSL_EC_curve_nid2nist(nid);
        wolfSSL_EC_POINT_dump("wolfSSL_EC_POINT_add p1", p1);
        wolfSSL_EC_POINT_dump("wolfSSL_EC_POINT_add p2", p2);
        if (curve != NULL)
            WOLFSSL_MSG_EX("curve name: %s", curve);
        if (nistName != NULL)
            WOLFSSL_MSG_EX("nist curve name: %s", nistName);
    }
#endif

    if (ret == 1) {
        /* Add points using wolfCrypt objects. */
        ret = wolfssl_ec_point_add(group->curve_idx, (ecc_point*)r->internal,
            (ecc_point*)p1->internal, (ecc_point*)p2->internal);
    }

    /* Copy internal EC point values out to external EC point. */
    if ((ret == 1) && (ec_point_external_set(r) != 1)) {
        WOLFSSL_MSG("ec_point_external_set error");
        ret = 0;
    }

#ifdef DEBUG_WOLFSSL
    if (ret == 1) {
        wolfSSL_EC_POINT_dump("wolfSSL_EC_POINT_add result", r);
    }
#endif

    return ret;
}

/* Sum the scalar multiplications of the base point and n, and q and m.
 *
 * r = base point * n + q * m
 *
 * @param [out] r      EC point that is result of operation.
 * @param [in]  b      Base point of curve.
 * @param [in]  n      Scalar to multiply by base point.
 * @param [in]  q      EC point to be scalar multiplied.
 * @param [in]  m      Scalar to multiply q by.
 * @param [in]  a      Parameter A of curve.
 * @param [in]  prime  Prime (modulus) of curve.
 * @return  1 on success.
 * @return  0 on error.
 */
static int ec_mul2add(ecc_point* r, ecc_point* b, mp_int* n, ecc_point* q,
    mp_int* m, mp_int* a, mp_int* prime)
{
    int ret = 1;
#if defined(ECC_SHAMIR) && !defined(WOLFSSL_KCAPI_ECC)
    if (ecc_mul2add(b, n, q, m, r, a, prime, NULL) != MP_OKAY) {
        WOLFSSL_MSG("ecc_mul2add error");
        ret = 0;
    }
#else
    ecc_point* tmp = NULL;
    mp_digit mp = 0;

    /* Calculate Montgomery product. */
    if (mp_montgomery_setup(prime, &mp) != MP_OKAY) {
        WOLFSSL_MSG("mp_montgomery_setup nqm error");
        ret = 0;
    }
    /* Create temporary point to hold: q * m */
    if ((ret == 1) && ((tmp = wc_ecc_new_point()) == NULL)) {
        WOLFSSL_MSG("wolfSSL_EC_POINT_new nqm error");
        ret = 0;
    }
    /* r = base point * n */
    if ((ret == 1) && (wc_ecc_mulmod(n, b, r, a, prime, 0) !=
            MP_OKAY)) {
        WOLFSSL_MSG("wc_ecc_mulmod nqm error");
        ret = 0;
    }
    /* tmp = q * m */
    if ((ret == 1) && (wc_ecc_mulmod(m, q, tmp, a, prime, 0) != MP_OKAY)) {
        WOLFSSL_MSG("wc_ecc_mulmod nqm error");
        ret = 0;
    }
    /* r = r + tmp */
    if ((ret == 1) && (ecc_projective_add_point(tmp, r, r, a, prime, mp) !=
            MP_OKAY)) {
        WOLFSSL_MSG("wc_ecc_mulmod nqm error");
        ret = 0;
    }
    /* Map point back to affine coordinates. Converts from Montogomery
     * form. */
    if ((ret == 1) && (ecc_map(r, prime, mp) != MP_OKAY)) {
        WOLFSSL_MSG("ecc_map nqm error");
        ret = 0;
    }

    /* Dispose of allocated temporary point. */
    wc_ecc_del_point(tmp);
#endif

    return ret;
}

/* Sum the scalar multiplications of the base point and n, and q and m.
 *
 * r = base point * n + q * m
 *
 * @param [in]  curveIdx  Index of curve in ecc_set.
 * @param [out] r         EC point that is result of operation.
 * @param [in]  n         Scalar to multiply by base point. May be NULL.
 * @param [in]  q         EC point to be scalar multiplied. May be NULL.
 * @param [in]  m         Scalar to multiply q by. May be NULL.
 * @return  1 on success.
 * @return  0 on error.
 */
static int wolfssl_ec_point_mul(int curveIdx, ecc_point* r, mp_int* n,
    ecc_point* q, mp_int* m)
{
    int ret = 1;
#ifdef WOLFSSL_SMALL_STACK
    mp_int* a = NULL;
    mp_int* prime = NULL;
#else
    mp_int a[1], prime[1];
#endif

#ifdef WOLFSSL_SMALL_STACK
    /* Allocate MP integer for curve parameter: a. */
    a = (mp_int*)XMALLOC(sizeof(mp_int), NULL, DYNAMIC_TYPE_BIGINT);
    if (a == NULL) {
        ret = 0;
    }
    if (ret == 1) {
        /* Allocate MP integer for curve parameter: prime. */
        prime = (mp_int*)XMALLOC(sizeof(mp_int), NULL, DYNAMIC_TYPE_BIGINT);
        if (prime == NULL)  {
            ret = 0;
        }
    }
#endif

    /* Initialize the MP ints. */
    if ((ret == 1) && (mp_init_multi(prime, a, NULL, NULL, NULL, NULL) !=
             MP_OKAY)) {
        WOLFSSL_MSG("mp_init_multi error");
        ret = 0;
    }

    /* Read the curve parameter: prime. */
    if ((ret == 1) && (mp_read_radix(prime, ecc_sets[curveIdx].prime,
            MP_RADIX_HEX) != MP_OKAY)) {
        WOLFSSL_MSG("mp_read_radix prime error");
        ret = 0;
    }

    /* Read the curve parameter: a. */
    if ((ret == 1) && (mp_read_radix(a, ecc_sets[curveIdx].Af,
            MP_RADIX_HEX) != MP_OKAY)) {
        WOLFSSL_MSG("mp_read_radix a error");
        ret = 0;
    }

    if ((ret == 1) && (n != NULL)) {
        /* Get generator - base point. */
    #if !defined(HAVE_FIPS) || FIPS_VERSION_GT(2,0)
        if ((ret == 1) && (wc_ecc_get_generator(r, curveIdx) != MP_OKAY)) {
            WOLFSSL_MSG("wc_ecc_get_generator error");
            ret = 0;
        }
    #else
        /* wc_ecc_get_generator is not defined in the FIPS v2 module. */
        /* Read generator (base point) x-ordinate. */
        if ((ret == 1) && (mp_read_radix(r->x, ecc_sets[curveIdx].Gx,
                MP_RADIX_HEX) != MP_OKAY)) {
            WOLFSSL_MSG("mp_read_radix Gx error");
            ret = 0;
        }
        /* Read generator (base point) y-ordinate. */
        if ((ret == 1) && (mp_read_radix(r->y, ecc_sets[curveIdx].Gy,
                MP_RADIX_HEX) != MP_OKAY)) {
            WOLFSSL_MSG("mp_read_radix Gy error");
            ret = 0;
        }
        /* z-ordinate is one as point is affine. */
        if ((ret == 1) && (mp_set(r->z, 1) != MP_OKAY)) {
            WOLFSSL_MSG("mp_set Gz error");
            ret = 0;
        }
    #endif /* NOPT_FIPS_VERSION == 2 */
    }

    if ((ret == 1) && (n != NULL) && (q != NULL) && (m != NULL)) {
        /* r = base point * n + q * m */
        ret = ec_mul2add(r, r, n, q, m, a, prime);
    }
    /* Not all values present, see if we are only doing base point * n. */
    else if ((ret == 1) && (n != NULL)) {
        /* r = base point * n */
        if (wc_ecc_mulmod(n, r, r, a, prime, 1) != MP_OKAY) {
            WOLFSSL_MSG("wc_ecc_mulmod gn error");
            ret = 0;
        }
    }
    /* Not all values present, see if we are only doing q * m. */
    else if ((ret == 1) && (q != NULL) && (m != NULL)) {
        /* r = q * m */
        if (wc_ecc_mulmod(m, q, r, a, prime, 1) != MP_OKAY) {
            WOLFSSL_MSG("wc_ecc_mulmod qm error");
            ret = 0;
        }
    }
    /* No values to use. */
    else if (ret == 1) {
        /* Set result to infinity as no values passed in. */
        mp_zero(r->x);
        mp_zero(r->y);
        mp_zero(r->z);
    }

    mp_clear(a);
    mp_clear(prime);
#ifdef WOLFSSL_SMALL_STACK
    XFREE(a, NULL, DYNAMIC_TYPE_BIGINT);
    XFREE(prime, NULL, DYNAMIC_TYPE_BIGINT);
#endif
    return ret;
}

/* Sum the scalar multiplications of the base point and n, and q and m.
 *
 * r = base point * n + q * m
 *
 * Return code compliant with OpenSSL.
 *
 * @param [in]  group  EC group.
 * @param [out] r      EC point that is result of operation.
 * @param [in]  n      Scalar to multiply by base point. May be NULL.
 * @param [in]  q      EC point to be scalar multiplied. May be NULL.
 * @param [in]  m      Scalar to multiply q by. May be NULL.
 * @param [in]  ctx    Context to use for BN operations. Unused.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_EC_POINT_mul(const WOLFSSL_EC_GROUP *group, WOLFSSL_EC_POINT *r,
    const WOLFSSL_BIGNUM *n, const WOLFSSL_EC_POINT *q, const WOLFSSL_BIGNUM *m,
    WOLFSSL_BN_CTX *ctx)
{
    int ret = 1;

    /* No BN operations performed. */
    (void)ctx;

    WOLFSSL_ENTER("wolfSSL_EC_POINT_mul");

    /* Validate parameters. */
    if ((group == NULL) || (r == NULL)) {
        WOLFSSL_MSG("wolfSSL_EC_POINT_mul NULL error");
        ret = 0;
    }

    /* Ensure the internal representation of the EC point q is setup. */
    if ((ret == 1) && (q != NULL) && (ec_point_setup(q) != 1)) {
        WOLFSSL_MSG("ec_point_setup error");
        ret = 0;
    }

#ifdef DEBUG_WOLFSSL
    if (ret == 1) {
        int nid = wolfSSL_EC_GROUP_get_curve_name(group);
        const char* curve = wolfSSL_OBJ_nid2ln(nid);
        const char* nistName = wolfSSL_EC_curve_nid2nist(nid);
        char* num;
        wolfSSL_EC_POINT_dump("wolfSSL_EC_POINT_mul input q", q);
        num = wolfSSL_BN_bn2hex(n);
        WOLFSSL_MSG_EX("\tn = %s", num);
        XFREE(num, NULL, DYNAMIC_TYPE_OPENSSL);
        num = wolfSSL_BN_bn2hex(m);
        WOLFSSL_MSG_EX("\tm = %s", num);
        XFREE(num, NULL, DYNAMIC_TYPE_OPENSSL);
        if (curve != NULL)
            WOLFSSL_MSG_EX("curve name: %s", curve);
        if (nistName != NULL)
            WOLFSSL_MSG_EX("nist curve name: %s", nistName);
    }
#endif

    if (ret == 1) {
        mp_int* ni = (n != NULL) ? (mp_int*)n->internal : NULL;
        ecc_point* qi = (q != NULL) ? (ecc_point*)q->internal : NULL;
        mp_int* mi = (m != NULL) ? (mp_int*)m->internal : NULL;

        /* Perform multiplication with wolfCrypt objects. */
        ret = wolfssl_ec_point_mul(group->curve_idx, (ecc_point*)r->internal,
            ni, qi, mi);
    }

    /* Only on success is the internal point guaranteed to be set. */
    if (r != NULL) {
        r->inSet = (ret == 1);
    }
    /* Copy internal EC point values out to external EC point. */
    if ((ret == 1) && (ec_point_external_set(r) != 1)) {
        WOLFSSL_MSG("ec_point_external_set error");
        ret = 0;
    }

#ifdef DEBUG_WOLFSSL
    if (ret == 1) {
        wolfSSL_EC_POINT_dump("wolfSSL_EC_POINT_mul result", r);
    }
#endif

    return ret;
}
#endif /* !WOLFSSL_ATECC508A && !WOLFSSL_ATECC608A && !HAVE_SELFTEST &&
        * !WOLFSSL_SP_MATH */

/* Invert the point on the curve.
 * (x, y) -> (x, -y) = (x, (prime - y) % prime)
 *
 * @param [in]      curveIdx  Index of curve in ecc_set.
 * @param [in, out] point     EC point to invert.
 * @return  1 on success.
 * @return  0 on error.
 */
static int wolfssl_ec_point_invert(int curveIdx, ecc_point* point)
{
    int ret = 1;
#ifdef WOLFSSL_SMALL_STACK
    mp_int* prime = NULL;
#else
    mp_int prime[1];
#endif

#ifdef WOLFSSL_SMALL_STACK
    /* Allocate memory for an MP int to hold the prime of the curve. */
    prime = (mp_int*)XMALLOC(sizeof(mp_int), NULL, DYNAMIC_TYPE_BIGINT);
    if (prime == NULL) {
        ret = 0;
    }
#endif

    /* Initialize MP int. */
    if ((ret == 1) && (mp_init(prime) != MP_OKAY)) {
        WOLFSSL_MSG("mp_init_multi error");
        ret = 0;
    }

    /* Read the curve parameter: prime. */
    if ((ret == 1) && (mp_read_radix(prime, ecc_sets[curveIdx].prime,
            MP_RADIX_HEX) != MP_OKAY)) {
        WOLFSSL_MSG("mp_read_radix prime error");
        ret = 0;
    }

    /* y = (prime - y) mod prime. */
    if ((ret == 1) && (!mp_iszero(point->y)) && (mp_sub(prime, point->y,
            point->y) != MP_OKAY)) {
        WOLFSSL_MSG("mp_sub error");
        ret = 0;
    }

    /* Dispose of memory associated with MP. */
    mp_free(prime);
#ifdef WOLFSSL_SMALL_STACK
    /* Dispose of dynamically allocated temporaries. */
    XFREE(prime, NULL, DYNAMIC_TYPE_BIGINT);
#endif
    return ret;
}

/* Invert the point on the curve.
 * (x, y) -> (x, -y) = (x, (prime - y) % prime)
 *
 * @param [in]      group  EC group.
 * @param [in, out] point  EC point to invert.
 * @param [in]      ctx    Context to use for BN operations. Unused.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_EC_POINT_invert(const WOLFSSL_EC_GROUP *group,
    WOLFSSL_EC_POINT *point, WOLFSSL_BN_CTX *ctx)
{
    int ret = 1;

    /* No BN operations performed. */
    (void)ctx;

    WOLFSSL_ENTER("wolfSSL_EC_POINT_invert");

    /* Validate parameters. */
    if ((group == NULL) || (point == NULL) || (point->internal == NULL)) {
        ret = 0;
    }

    /* Ensure internal representation of point is setup. */
    if ((ret == 1) && (ec_point_setup(point) != 1)) {
        ret = 0;
    }

#ifdef DEBUG_WOLFSSL
    if (ret == 1) {
        int nid = wolfSSL_EC_GROUP_get_curve_name(group);
        const char* curve = wolfSSL_OBJ_nid2ln(nid);
        const char* nistName = wolfSSL_EC_curve_nid2nist(nid);
        wolfSSL_EC_POINT_dump("wolfSSL_EC_POINT_invert input", point);
        if (curve != NULL)
            WOLFSSL_MSG_EX("curve name: %s", curve);
        if (nistName != NULL)
            WOLFSSL_MSG_EX("nist curve name: %s", nistName);

    }
#endif

    if (ret == 1 && !wolfSSL_BN_is_one(point->Z)) {
#if !defined(WOLFSSL_SP_MATH) && !defined(WOLF_CRYPTO_CB_ONLY_ECC)
        if (ec_point_convert_to_affine(group, point) != 0)
            ret = 0;
#else
        WOLFSSL_MSG("wolfSSL_EC_POINT_invert called on non-affine point");
        ret = 0;
#endif
    }

    if (ret == 1) {
        /* Perform inversion using wolfCrypt objects. */
        ret = wolfssl_ec_point_invert(group->curve_idx,
            (ecc_point*)point->internal);
    }

    /* Set the external EC point representation based on internal. */
    if ((ret == 1) && (ec_point_external_set(point) != 1)) {
        WOLFSSL_MSG("ec_point_external_set error");
        ret = 0;
    }

#ifdef DEBUG_WOLFSSL
    if (ret == 1) {
        wolfSSL_EC_POINT_dump("wolfSSL_EC_POINT_invert result", point);
    }
#endif

    return ret;
}

#ifdef WOLFSSL_EC_POINT_CMP_JACOBIAN
/* Compare two points on a the same curve.
 *
 * (Ax, Ay, Az) => (Ax / (Az ^ 2), Ay / (Az ^ 3))
 * (Bx, By, Bz) => (Bx / (Bz ^ 2), By / (Bz ^ 3))
 * When equal:
 *      (Ax / (Az ^ 2), Ay / (Az ^ 3)) = (Bx / (Bz ^ 2), By / (Bz ^ 3))
 *   => (Ax * (Bz ^ 2), Ay * (Bz ^ 3)) = (Bx * (Az ^ 2), By * (Az ^ 3))
 *
 * @param [in] group  EC group.
 * @param [in] a      EC point to compare.
 * @param [in] b      EC point to compare.
 * @return  0 when equal.
 * @return  1 when different.
 * @return  -1 on error.
 */
static int ec_point_cmp_jacobian(const WOLFSSL_EC_GROUP* group,
    const WOLFSSL_EC_POINT *a, const WOLFSSL_EC_POINT *b, WOLFSSL_BN_CTX *ctx)
{
    int ret = 0;
    BIGNUM* at = BN_new();
    BIGNUM* bt = BN_new();
    BIGNUM* az = BN_new();
    BIGNUM* bz = BN_new();
    BIGNUM* mod = BN_new();

    /* Check that the big numbers were allocated. */
    if ((at == NULL) || (bt == NULL) || (az == NULL) || (bz == NULL) ||
            (mod == NULL)) {
        ret = -1;
    }
    /* Get the modulus for the curve. */
    if ((ret == 0) &&
            (BN_hex2bn(&mod, ecc_sets[group->curve_idx].prime) != 1)) {
        ret = -1;
    }
    if (ret == 0) {
        /* bt = Bx * (Az ^ 2). When Az is one then just copy. */
        if (BN_is_one(a->Z)) {
            if (BN_copy(bt, b->X) == NULL) {
                ret = -1;
            }
        }
        /* az = Az ^ 2 */
        else if ((BN_mod_mul(az, a->Z, a->Z, mod, ctx) != 1)) {
            ret = -1;
        }
        /* bt = Bx * az = Bx * (Az ^ 2) */
        else if (BN_mod_mul(bt, b->X, az, mod, ctx) != 1) {
            ret = -1;
        }
    }
    if (ret == 0) {
        /* at = Ax * (Bz ^ 2). When Bz is one then just copy. */
        if (BN_is_one(b->Z)) {
            if (BN_copy(at, a->X) == NULL) {
                ret = -1;
            }
        }
        /* bz = Bz ^ 2 */
        else if (BN_mod_mul(bz, b->Z, b->Z, mod, ctx) != 1) {
            ret = -1;
        }
        /* at = Ax * bz = Ax * (Bz ^ 2) */
        else if (BN_mod_mul(at, a->X, bz, mod, ctx) != 1) {
            ret = -1;
        }
    }
    /* Compare x-ordinates. */
    if ((ret == 0) && (BN_cmp(at, bt) != 0)) {
        ret = 1;
    }
    if (ret == 0) {
        /* bt = By * (Az ^ 3). When Az is one then just copy. */
        if (BN_is_one(a->Z)) {
            if (BN_copy(bt, b->Y) == NULL) {
                ret = -1;
            }
        }
        /* az = az * Az = Az ^ 3 */
        else if ((BN_mod_mul(az, az, a->Z, mod, ctx) != 1)) {
            ret = -1;
        }
        /* bt = By * az = By * (Az ^ 3) */
        else if (BN_mod_mul(bt, b->Y, az, mod, ctx) != 1) {
            ret = -1;
        }
    }
    if (ret == 0) {
        /* at = Ay * (Bz ^ 3). When Bz is one then just copy. */
        if (BN_is_one(b->Z)) {
            if (BN_copy(at, a->Y) == NULL) {
                ret = -1;
            }
        }
        /* bz = bz * Bz = Bz ^ 3 */
        else if (BN_mod_mul(bz, bz, b->Z, mod, ctx) != 1) {
            ret = -1;
        }
        /* at = Ay * bz = Ay * (Bz ^ 3) */
        else if (BN_mod_mul(at, a->Y, bz, mod, ctx) != 1) {
            ret = -1;
        }
    }
    /* Compare y-ordinates. */
    if ((ret == 0) && (BN_cmp(at, bt) != 0)) {
        ret = 1;
    }

    BN_free(mod);
    BN_free(bz);
    BN_free(az);
    BN_free(bt);
    BN_free(at);
    return ret;
}
#endif

/* Compare two points on a the same curve.
 *
 * Return code compliant with OpenSSL.
 *
 * @param [in] group  EC group.
 * @param [in] a      EC point to compare.
 * @param [in] b      EC point to compare.
 * @param [in] ctx    Context to use for BN operations. Unused.
 * @return  0 when equal.
 * @return  1 when different.
 * @return  -1 on error.
 */
int wolfSSL_EC_POINT_cmp(const WOLFSSL_EC_GROUP *group,
    const WOLFSSL_EC_POINT *a, const WOLFSSL_EC_POINT *b, WOLFSSL_BN_CTX *ctx)
{
    int ret = 0;

    WOLFSSL_ENTER("wolfSSL_EC_POINT_cmp");

    /* Validate parameters. */
    if ((group == NULL) || (a == NULL) || (a->internal == NULL) ||
            (b == NULL) || (b->internal == NULL)) {
        WOLFSSL_MSG("wolfSSL_EC_POINT_cmp Bad arguments");
        ret = -1;
    }
    if (ret != -1) {
    #ifdef WOLFSSL_EC_POINT_CMP_JACOBIAN
        /* If same Z ordinate then no need to convert to affine. */
        if (BN_cmp(a->Z, b->Z) == 0) {
            /* Compare */
            ret = ((BN_cmp(a->X, b->X) != 0) || (BN_cmp(a->Y, b->Y) != 0));
        }
        else {
            ret = ec_point_cmp_jacobian(group, a, b, ctx);
        }
    #else
        /* No BN operations performed. */
        (void)ctx;

        ret = (wc_ecc_cmp_point((ecc_point*)a->internal,
            (ecc_point*)b->internal) != MP_EQ);
    #endif
    }

    return ret;
}

/* Copy EC point.
 *
 * @param [out] dest  EC point to copy into.
 * @param [in]  src   EC point to copy.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_EC_POINT_copy(WOLFSSL_EC_POINT *dest, const WOLFSSL_EC_POINT *src)
{
    int ret = 1;

    WOLFSSL_ENTER("wolfSSL_EC_POINT_copy");

    /* Validate parameters. */
    if ((dest == NULL) || (src == NULL)) {
        ret = 0;
    }

    /* Ensure internal EC point of src is setup. */
    if ((ret == 1) && (ec_point_setup(src) != 1)) {
        ret = 0;
    }

    /* Copy internal EC points. */
    if ((ret == 1) && (wc_ecc_copy_point((ecc_point*)src->internal,
            (ecc_point*)dest->internal) != MP_OKAY)) {
        ret = 0;
    }

    if (ret == 1) {
        /* Destinatation internal point is set. */
        dest->inSet = 1;

        /* Set the external EC point of dest based on internal. */
        if (ec_point_external_set(dest) != 1) {
            ret = 0;
        }
    }

    return ret;
}

/* Checks whether point is at infinity.
 *
 * Return code compliant with OpenSSL.
 *
 * @param [in] group  EC group.
 * @param [in] point  EC point to check.
 * @return  1 when at infinity.
 * @return  0 when not at infinity.
 */
int wolfSSL_EC_POINT_is_at_infinity(const WOLFSSL_EC_GROUP *group,
    const WOLFSSL_EC_POINT *point)
{
    int ret = 1;

    WOLFSSL_ENTER("wolfSSL_EC_POINT_is_at_infinity");

    /* Validate parameters. */
    if ((group == NULL) || (point == NULL) || (point->internal == NULL)) {
        WOLFSSL_MSG("wolfSSL_EC_POINT_is_at_infinity NULL error");
        ret = 0;
    }

    /* Ensure internal EC point is setup. */
    if ((ret == 1) && (ec_point_setup(point) != 1)) {
        ret = 0;
    }
    if (ret == 1) {
    #ifndef WOLF_CRYPTO_CB_ONLY_ECC
        /* Check for infinity. */
        ret = wc_ecc_point_is_at_infinity((ecc_point*)point->internal);
        if (ret < 0) {
            WOLFSSL_MSG("ecc_point_is_at_infinity failure");
            /* Error return is 0 by OpenSSL. */
            ret = 0;
        }
    #else
        WOLFSSL_MSG("ecc_point_is_at_infinitiy compiled out");
        ret = 0;
    #endif
    }

    return ret;
}

#endif /* OPENSSL_EXTRA */

/* End EC_POINT */

/* Start EC_KEY */

#ifdef OPENSSL_EXTRA

/*
 * EC key constructor/deconstructor APIs
 */

/* Allocate a new EC key.
 *
 * Not OpenSSL API.
 *
 * @param [in] heap   Heap hint for dynamic memory allocation.
 * @param [in] devId  Device identifier value.
 * @return  New, allocated EC key on success.
 * @return  NULL on error.
 */
WOLFSSL_EC_KEY *wolfSSL_EC_KEY_new_ex(void* heap, int devId)
{
    WOLFSSL_EC_KEY *key = NULL;
    int err = 0;

    WOLFSSL_ENTER("wolfSSL_EC_KEY_new");

    /* Allocate memory for EC key. */
    key = (WOLFSSL_EC_KEY*)XMALLOC(sizeof(WOLFSSL_EC_KEY), heap,
        DYNAMIC_TYPE_ECC);
    if (key == NULL) {
        WOLFSSL_MSG("wolfSSL_EC_KEY_new malloc WOLFSSL_EC_KEY failure");
        err = 1;
    }
    if (!err) {
        /* Reset all fields to 0. */
        XMEMSET(key, 0, sizeof(WOLFSSL_EC_KEY));
        /* Cache heap hint. */
        key->heap = heap;
        /* Initialize fields to defaults. */
        key->form     = POINT_CONVERSION_UNCOMPRESSED;

        /* Initialize reference count. */
        wolfSSL_RefInit(&key->ref, &err);
#ifdef WOLFSSL_REFCNT_ERROR_RETURN
    }
    if (!err) {
#endif
        /* Allocate memory for internal EC key representation. */
        key->internal = (ecc_key*)XMALLOC(sizeof(ecc_key), heap,
            DYNAMIC_TYPE_ECC);
        if (key->internal == NULL) {
            WOLFSSL_MSG("wolfSSL_EC_KEY_new malloc ecc key failure");
            err = 1;
        }
    }
    if (!err) {
        /* Initialize wolfCrypt EC key. */
        if (wc_ecc_init_ex((ecc_key*)key->internal, heap, devId) != 0) {
            WOLFSSL_MSG("wolfSSL_EC_KEY_new init ecc key failure");
            err = 1;
        }
    }

    if (!err) {
        /* Group unknown at creation */
        key->group = wolfSSL_EC_GROUP_new_by_curve_name(NID_undef);
        if (key->group == NULL) {
            WOLFSSL_MSG("wolfSSL_EC_KEY_new malloc WOLFSSL_EC_GROUP failure");
            err = 1;
        }
    }

    if (!err) {
        /* Allocate a point as public key. */
        key->pub_key = wolfSSL_EC_POINT_new(key->group);
        if (key->pub_key == NULL) {
            WOLFSSL_MSG("wolfSSL_EC_POINT_new failure");
            err = 1;
        }
    }

    if (!err) {
        /* Allocate a BN as private key. */
        key->priv_key = wolfSSL_BN_new();
        if (key->priv_key == NULL) {
            WOLFSSL_MSG("wolfSSL_BN_new failure");
            err = 1;
        }
    }

    if (err) {
        /* Dispose of EC key on error. */
        wolfSSL_EC_KEY_free(key);
        key = NULL;
    }
    /* Return new EC key object. */
    return key;
}

/* Allocate a new EC key.
 *
 * @return  New, allocated EC key on success.
 * @return  NULL on error.
 */
WOLFSSL_EC_KEY *wolfSSL_EC_KEY_new(void)
{
    return wolfSSL_EC_KEY_new_ex(NULL, INVALID_DEVID);
}

/* Create new EC key with the group having the specified numeric ID.
 *
 * @param [in] nid  Numeric ID.
 * @return  New, allocated EC key on success.
 * @return  NULL on error.
 */
WOLFSSL_EC_KEY *wolfSSL_EC_KEY_new_by_curve_name(int nid)
{
    WOLFSSL_EC_KEY *key;
    int err = 0;

    WOLFSSL_ENTER("wolfSSL_EC_KEY_new_by_curve_name");

    /* Allocate empty, EC key. */
    key = wolfSSL_EC_KEY_new();
    if (key == NULL) {
        WOLFSSL_MSG("wolfSSL_EC_KEY_new failure");
        err = 1;
    }

    if (!err) {
        /* Set group to be nid. */
        ec_group_set_nid(key->group, nid);
        if (key->group->curve_idx == -1) {
            wolfSSL_EC_KEY_free(key);
            key = NULL;
        }
    }

    /* Return the new EC key object. */
    return key;
}

/* Dispose of the EC key and allocated data.
 *
 * Cannot use key after this call.
 *
 * @param [in] key  EC key to free.
 */
void wolfSSL_EC_KEY_free(WOLFSSL_EC_KEY *key)
{
    int doFree = 0;
    int err;

    (void)err;

    WOLFSSL_ENTER("wolfSSL_EC_KEY_free");

    if (key != NULL) {
        void* heap = key->heap;

        /* Decrement reference count. */
        wolfSSL_RefDec(&key->ref, &doFree, &err);
        if (doFree) {
            /* Dispose of allocated reference counting data. */
            wolfSSL_RefFree(&key->ref);

            /* Dispose of private key. */
            wolfSSL_BN_free(key->priv_key);
            wolfSSL_EC_POINT_free(key->pub_key);
            wolfSSL_EC_GROUP_free(key->group);
            if (key->internal != NULL) {
                /* Dispose of wolfCrypt representation of EC key. */
                wc_ecc_free((ecc_key*)key->internal);
                XFREE(key->internal, heap, DYNAMIC_TYPE_ECC);
            }

            /* Set back to NULLs for safety. */
            ForceZero(key, sizeof(*key));

            /* Dispose of the memory associated with the EC key. */
            XFREE(key, heap, DYNAMIC_TYPE_ECC);
            (void)heap;
        }
    }
}

/* Increments ref count of EC key.
 *
 * @param [in, out] key  EC key.
 * @return  1 on success
 * @return  0 on error
 */
int wolfSSL_EC_KEY_up_ref(WOLFSSL_EC_KEY* key)
{
    int err = 1;

    if (key != NULL) {
        wolfSSL_RefInc(&key->ref, &err);
    }

    return !err;
}

#ifndef NO_CERTS

#if defined(OPENSSL_ALL)
/* Copy the internal, wolfCrypt EC key.
 *
 * @param [in, out] dst  Destination wolfCrypt EC key.
 * @param [in]      src  Source wolfCrypt EC key.
 * @return  0 on success.
 * @return  Negative on error.
 */
static int wolfssl_ec_key_int_copy(ecc_key* dst, const ecc_key* src)
{
    int ret;

    /* Copy public key. */
#if !defined(HAVE_FIPS) || FIPS_VERSION_GT(2,0)
    ret = wc_ecc_copy_point(&src->pubkey, &dst->pubkey);
#else
    ret = wc_ecc_copy_point((ecc_point*)&src->pubkey, &dst->pubkey);
#endif
    if (ret != MP_OKAY) {
        WOLFSSL_MSG("wc_ecc_copy_point error");
    }

    if (ret == 0) {
        /* Copy private key. */
        ret = mp_copy(wc_ecc_key_get_priv((ecc_key*)src),
            wc_ecc_key_get_priv(dst));
        if (ret != MP_OKAY) {
            WOLFSSL_MSG("mp_copy error");
        }
    }

    if (ret == 0) {
        /* Copy domain parameters. */
        if (src->dp) {
            ret = wc_ecc_set_curve(dst, 0, src->dp->id);
            if (ret != 0) {
                WOLFSSL_MSG("wc_ecc_set_curve error");
            }
        }
    }

    if (ret == 0) {
        /* Copy the other components. */
        dst->type  = src->type;
        dst->idx   = src->idx;
        dst->state = src->state;
        dst->flags = src->flags;
    }

    return ret;
}

/* Copies ecc_key into new WOLFSSL_EC_KEY object
 *
 * Copies the internal representation as well.
 *
 * @param [in] src  EC key to duplicate.
 *
 * @return  EC key on success.
 * @return  NULL on error.
 */
WOLFSSL_EC_KEY *wolfSSL_EC_KEY_dup(const WOLFSSL_EC_KEY *src)
{
    int err = 0;
    WOLFSSL_EC_KEY* newKey = NULL;

    WOLFSSL_ENTER("wolfSSL_EC_KEY_dup");

    /* Validate EC key. */
    if ((src == NULL) || (src->internal == NULL) || (src->group == NULL) ||
         (src->pub_key == NULL) || (src->priv_key == NULL)) {
        WOLFSSL_MSG("src NULL error");
        err = 1;
    }

    if (!err) {
        /* Create a new, empty key. */
        newKey = wolfSSL_EC_KEY_new();
        if (newKey == NULL) {
            WOLFSSL_MSG("wolfSSL_EC_KEY_new error");
            err = 1;
        }
    }

    if (!err) {
        /* Copy internal EC key. */
        if (wolfssl_ec_key_int_copy((ecc_key*)newKey->internal,
                (ecc_key*)src->internal) != 0) {
            WOLFSSL_MSG("Copying internal EC key error");
            err = 1;
        }
    }
    if (!err) {
        /* Internal key set. */
        newKey->inSet = 1;

        /* Copy group */
        err = wolfssl_ec_group_copy(newKey->group, src->group);
    }
    /* Copy public key. */
    if ((!err) && (wolfSSL_EC_POINT_copy(newKey->pub_key, src->pub_key) != 1)) {
        WOLFSSL_MSG("Copying EC public key error");
        err = 1;
    }

    if (!err) {
        /* Set header size of private key in PKCS#8 format.*/
        newKey->pkcs8HeaderSz = src->pkcs8HeaderSz;

        /* Copy private key. */
        if (wolfSSL_BN_copy(newKey->priv_key, src->priv_key) == NULL) {
            WOLFSSL_MSG("Copying EC private key error");
            err = 1;
        }
    }

    if (err) {
        /* Dispose of EC key on error. */
        wolfSSL_EC_KEY_free(newKey);
        newKey = NULL;
    }
    /* Return the new EC key. */
    return newKey;
}

#endif /* OPENSSL_ALL */

#endif /* !NO_CERTS */

/*
 * EC key to/from bin/octet APIs
 */

/* Create an EC key from the octet encoded public key.
 *
 * Behaviour checked against OpenSSL.
 *
 * @param [out]     key  Reference to EC key. Must pass in a valid object with
 *                       group set.
 * @param [in, out] in   On in, reference to buffer that contains data.
 *                       On out, reference to buffer after public key data.
 * @param [in]      len  Length of data in the buffer. Must be length of the
 *                       encoded public key.
 * @return  Allocated EC key on success.
 * @return  NULL on error.
 */
WOLFSSL_EC_KEY *wolfSSL_o2i_ECPublicKey(WOLFSSL_EC_KEY **key,
   const unsigned char **in, long len)
{
    int err = 0;
    WOLFSSL_EC_KEY* ret = NULL;

    WOLFSSL_ENTER("wolfSSL_o2i_ECPublicKey");

    /* Validate parameters: EC group needed to perform import. */
    if ((key == NULL) || (*key == NULL) || ((*key)->group == NULL) ||
            (in == NULL) || (*in == NULL) || (len <= 0)) {
        WOLFSSL_MSG("wolfSSL_o2i_ECPublicKey Bad arguments");
        err = 1;
    }

    if (!err) {
        /* Return the EC key object passed in. */
        ret = *key;

        /* Import point into public key field. */
        if (wolfSSL_EC_POINT_oct2point(ret->group, ret->pub_key, *in,
                (size_t)len, NULL) != 1) {
            WOLFSSL_MSG("wolfSSL_EC_POINT_oct2point error");
            ret = NULL;
            err = 1;
        }
    }
    if (!err) {
        /* Assumed length passed in is all the data. */
        *in += len;
    }

    return ret;
}

/* Puts the encoded public key into out.
 *
 * Passing in NULL for out returns length only.
 * Passing in NULL for *out has buffer allocated, encoded into and passed back.
 * Passing non-NULL for *out has it encoded into and pointer moved past.
 *
 * @param [in]      key  EC key to encode.
 * @param [in, out] out  Reference to buffer to encode into. May be NULL or
 *                       point to NULL.
 * @return  Length of encoding in bytes on success.
 * @return  0 on error.
 */
int wolfSSL_i2o_ECPublicKey(const WOLFSSL_EC_KEY *key, unsigned char **out)
{
    int ret = 1;
    size_t len = 0;
    int form = POINT_CONVERSION_UNCOMPRESSED;

    WOLFSSL_ENTER("wolfSSL_i2o_ECPublicKey");

    /* Validate parameters. */
    if (key == NULL) {
        WOLFSSL_MSG("wolfSSL_i2o_ECPublicKey Bad arguments");
        ret = 0;
    }

    /* Ensure the external key data is set from the internal EC key. */
    if ((ret == 1) && (!key->exSet) && (SetECKeyExternal((WOLFSSL_EC_KEY*)
            key) != 1)) {
        WOLFSSL_MSG("SetECKeyExternal failure");
        ret = 0;
    }

    if (ret == 1) {
    #ifdef HAVE_COMP_KEY
        /* Default to compressed form if not set */
        form = (key->form != POINT_CONVERSION_UNCOMPRESSED) ?
               POINT_CONVERSION_UNCOMPRESSED :
               POINT_CONVERSION_COMPRESSED;
    #endif

        /* Calculate length of point encoding. */
        len = wolfSSL_EC_POINT_point2oct(key->group, key->pub_key, form, NULL,
            0, NULL);
    }
    /* Encode if length calculated and pointer supplied to update. */
    if ((ret == 1) && (len != 0) && (out != NULL)) {
        unsigned char *tmp = NULL;

        /* Allocate buffer for encoding if no buffer supplied. */
        if (*out == NULL) {
            tmp = (unsigned char*)XMALLOC(len, NULL, DYNAMIC_TYPE_OPENSSL);
            if (tmp == NULL) {
                WOLFSSL_MSG("malloc failed");
                ret = 0;
            }
        }
        else {
            /* Get buffer to encode into. */
            tmp = *out;
        }

        /* Encode public key into buffer. */
        if ((ret == 1) && (wolfSSL_EC_POINT_point2oct(key->group, key->pub_key,
                form, tmp, len, NULL) == 0)) {
            ret = 0;
        }

        if (ret == 1) {
            /* Return buffer if allocated. */
            if (*out == NULL) {
                *out = tmp;
            }
            else {
                /* Step over encoded data if not allocated. */
                *out += len;
            }
        }
        else if (*out == NULL) {
            /* Dispose of allocated buffer. */
            XFREE(tmp, NULL, DYNAMIC_TYPE_OPENSSL);
        }
    }

    if (ret == 1) {
        /* Return length on success. */
        ret = (int)len;
    }
    return ret;
}

#ifdef HAVE_ECC_KEY_IMPORT
/* Create a EC key from the DER encoded private key.
 *
 * @param [out]     key   Reference to EC key.
 * @param [in, out] in    On in, reference to buffer that contains DER data.
 *                        On out, reference to buffer after private key data.
 * @param [in]      long  Length of data in the buffer. May be larger than the
 *                        length of the encoded private key.
 * @return  Allocated EC key on success.
 * @return  NULL on error.
 */
WOLFSSL_EC_KEY* wolfSSL_d2i_ECPrivateKey(WOLFSSL_EC_KEY** key,
    const unsigned char** in, long len)
{
    int err = 0;
    word32 idx = 0;
    WOLFSSL_EC_KEY* ret = NULL;

    WOLFSSL_ENTER("wolfSSL_d2i_ECPrivateKey");

    /* Validate parameters. */
    if ((in == NULL) || (*in == NULL) || (len <= 0)) {
        WOLFSSL_MSG("wolfSSL_d2i_ECPrivateKey Bad arguments");
        err = 1;
    }

    /* Create a new, empty EC key.  */
    if ((!err) && ((ret = wolfSSL_EC_KEY_new()) == NULL)) {
        WOLFSSL_MSG("wolfSSL_EC_KEY_new error");
        err = 1;
    }

    /* Decode the private key DER data into internal EC key. */
    if ((!err) && (wc_EccPrivateKeyDecode(*in, &idx, (ecc_key*)ret->internal,
            (word32)len) != 0)) {
        WOLFSSL_MSG("wc_EccPrivateKeyDecode error");
        err = 1;
    }

    if (!err) {
        /* Internal EC key setup. */
        ret->inSet = 1;

        /* Set the EC key from the internal values. */
        if (SetECKeyExternal(ret) != 1) {
            WOLFSSL_MSG("SetECKeyExternal error");
            err = 1;
        }
    }

    if (!err) {
        /* Move buffer on to next byte after data used. */
        *in += idx;
        if (key) {
            /* Return new EC key through reference. */
            *key = ret;
        }
    }

    if (err && (ret != NULL)) {
        /* Dispose of allocated EC key. */
        wolfSSL_EC_KEY_free(ret);
        ret = NULL;
    }
    return ret;
}
#endif /* HAVE_ECC_KEY_IMPORT */

/* Enecode the private key of the EC key into the buffer as DER.
 *
 * @param [in]      key  EC key to encode.
 * @param [in, out] out  On in, reference to buffer to place DER encoding into.
 *                       On out, reference to buffer adter the encoding.
 *                       May be NULL.
 * @return  Length of DER encoding on success.
 * @return  0 on error.
 */
int wolfSSL_i2d_ECPrivateKey(const WOLFSSL_EC_KEY *key, unsigned char **out)
{
    int err = 0;
    word32 len = 0;

    WOLFSSL_ENTER("wolfSSL_i2d_ECPrivateKey");

    /* Validate parameters. */
    if (key == NULL) {
        WOLFSSL_MSG("wolfSSL_i2d_ECPrivateKey Bad arguments");
        err = 1;
    }

    /* Update the internal EC key if not set. */
    if ((!err) && (!key->inSet) && (SetECKeyInternal((WOLFSSL_EC_KEY*)key) !=
            1)) {
        WOLFSSL_MSG("SetECKeyInternal error");
        err = 1;
    }

    /* Calculate the length of the private key DER encoding using internal EC
     * key. */
    if ((!err) && ((int)(len = (word32)wc_EccKeyDerSize((ecc_key*)key->internal,
           0)) <= 0)) {
        WOLFSSL_MSG("wc_EccKeyDerSize error");
        err = 1;
    }

    /* Only return length when out is NULL. */
    if ((!err) && (out != NULL)) {
        unsigned char* buf = NULL;

        /* Must have a buffer to encode into. */
        if (*out == NULL) {
            /* Allocate a new buffer of appropriate length. */
            buf = (byte*)XMALLOC(len, NULL, DYNAMIC_TYPE_TMP_BUFFER);
            if (buf == NULL) {
                /* Error and return 0. */
                err = 1;
                len = 0;
            }
            else {
                /* Return the allocated buffer. */
                *out = buf;
            }
        }
        /* Encode the internal EC key as a private key in DER format. */
        if ((!err) && wc_EccPrivateKeyToDer((ecc_key*)key->internal, *out,
                len) < 0) {
            WOLFSSL_MSG("wc_EccPrivateKeyToDer error");
            err = 1;
        }
        else if (buf != *out) {
            /* Move the reference to byte past encoded private key. */
            *out += len;
        }

        /* Dispose of any allocated buffer on error. */
        if (err && (*out == buf)) {
            XFREE(buf, NULL, DYNAMIC_TYPE_TMP_BUFFER);
            *out = NULL;
        }
    }

    return (int)len;
}

/* Load private key into EC key from DER encoding.
 *
 * Not an OpenSSL compatibility API.
 *
 * @param [in, out] key     EC key to put private key values into.
 * @param [in]      derBuf  Buffer holding DER encoding.
 * @param [in]      derSz   Size of DER encoding in bytes.
 * @return  1 on success.
 * @return  -1 on error.
 */
int wolfSSL_EC_KEY_LoadDer(WOLFSSL_EC_KEY* key, const unsigned char* derBuf,
                           int derSz)
{
    return wolfSSL_EC_KEY_LoadDer_ex(key, derBuf, derSz,
        WOLFSSL_EC_KEY_LOAD_PRIVATE);
}

/* Load private/public key into EC key from DER encoding.
 *
 * Not an OpenSSL compatibility API.
 *
 * @param [in, out] key     EC key to put private/public key values into.
 * @param [in]      derBuf  Buffer holding DER encoding.
 * @param [in]      derSz   Size of DER encoding in bytes.
 * @param [in]      opt     Key type option. Valid values:
 *                            WOLFSSL_EC_KEY_LOAD_PRIVATE,
 *                            WOLFSSL_EC_KEY_LOAD_PUBLIC.
 * @return  1 on success.
 * @return  -1 on error.
 */
int wolfSSL_EC_KEY_LoadDer_ex(WOLFSSL_EC_KEY* key, const unsigned char* derBuf,
                              int derSz, int opt)
{
    int res = 1;
    int ret;
    word32 idx = 0;
    word32 algId;

    WOLFSSL_ENTER("wolfSSL_EC_KEY_LoadDer");

    /* Validate parameters. */
    if ((key == NULL) || (key->internal == NULL) || (derBuf == NULL) ||
            (derSz <= 0)) {
        WOLFSSL_MSG("Bad function arguments");
        res = -1;
    }
    if ((res == 1) && (opt != WOLFSSL_EC_KEY_LOAD_PRIVATE) &&
            (opt != WOLFSSL_EC_KEY_LOAD_PUBLIC)) {
        res = -1;
    }

    if (res == 1) {
        /* Assume no PKCS#8 header. */
        key->pkcs8HeaderSz = 0;

        /* Check if input buffer has PKCS8 header. In the case that it does not
         * have a PKCS8 header then do not error out.
         */
        if ((ret = ToTraditionalInline_ex((const byte*)derBuf, &idx,
                (word32)derSz, &algId)) > 0) {
            WOLFSSL_MSG("Found PKCS8 header");
            key->pkcs8HeaderSz = (word16)idx;
            res = 1;
        }
        /* Error out on parsing error. */
        else if (ret != WC_NO_ERR_TRACE(ASN_PARSE_E)) {
            WOLFSSL_MSG("Unexpected error with trying to remove PKCS8 header");
            res = -1;
        }
    }

    if (res == 1) {
        /* Load into internal EC key based on key type option. */
        if (opt == WOLFSSL_EC_KEY_LOAD_PRIVATE) {
            ret = wc_EccPrivateKeyDecode(derBuf, &idx, (ecc_key*)key->internal,
                (word32)derSz);
        }
        else {
            ret = wc_EccPublicKeyDecode(derBuf, &idx, (ecc_key*)key->internal,
                (word32)derSz);
            if (ret < 0) {
                ecc_key *tmp = (ecc_key*)XMALLOC(sizeof(ecc_key),
                    ((ecc_key*)key->internal)->heap, DYNAMIC_TYPE_ECC);
                if (tmp == NULL) {
                    ret = -1;
                }
                else {
                    /* We now try again as x.963 [point type][x][opt y]. */
                    ret = wc_ecc_init_ex(tmp, ((ecc_key*)key->internal)->heap,
                                         INVALID_DEVID);
                    if (ret == 0) {
                        ret = wc_ecc_import_x963(derBuf, (word32)derSz, tmp);
                        if (ret == 0) {
                            /* Take ownership of new key - set tmp to the old
                             * key which will then be freed below. */
                            ecc_key *old = (ecc_key *)key->internal;
                            key->internal = tmp;
                            tmp = old;

                            idx = (word32)derSz;
                        }
                        wc_ecc_free(tmp);
                    }
                    XFREE(tmp, ((ecc_key*)key->internal)->heap,
                          DYNAMIC_TYPE_ECC);
                }
            }
        }
        if (ret < 0) {
            /* Error returned from wolfSSL. */
            if (opt == WOLFSSL_EC_KEY_LOAD_PRIVATE) {
                WOLFSSL_MSG("wc_EccPrivateKeyDecode failed");
            }
            else {
                WOLFSSL_MSG("wc_EccPublicKeyDecode failed");
            }
            res = -1;
        }

        /* Internal key updated - update whether it is a valid key. */
        key->inSet = (res == 1);
    }

    /* Set the external EC key based on value in internal. */
    if ((res == 1) && (SetECKeyExternal(key) != 1)) {
        WOLFSSL_MSG("SetECKeyExternal failed");
        res = -1;
    }

    return res;
}

/*
 * EC key PEM APIs
 */

#ifdef HAVE_ECC_KEY_EXPORT
#if defined(WOLFSSL_KEY_GEN) && (!defined(NO_FILESYSTEM) || !defined(NO_BIO))
/* Encode the EC public key as DER.
 *
 * @param [in]  key   EC key to encode.
 * @param [out] der   Pointer through which buffer is returned.
 * @param [in]  heap  Heap hint.
 * @return  Size of encoding on success.
 * @return  0 on error.
 */
static int wolfssl_ec_key_to_pubkey_der(WOLFSSL_EC_KEY* key,
    unsigned char** der, void* heap)
{
    int sz;
    unsigned char* buf = NULL;

    (void)heap;

    /* Calculate encoded size to allocate. */
    sz = wc_EccPublicKeyDerSize((ecc_key*)key->internal, 1);
    if (sz <= 0) {
        WOLFSSL_MSG("wc_EccPublicKeyDerSize failed");
        sz = 0;
    }
    if (sz > 0) {
        /* Allocate memory to hold encoding. */
        buf = (byte*)XMALLOC((size_t)sz, heap, DYNAMIC_TYPE_TMP_BUFFER);
        if (buf == NULL) {
            WOLFSSL_MSG("malloc failed");
            sz = 0;
        }
    }
    if (sz > 0) {
        /* Encode public key to DER using wolfSSL.  */
        sz = wc_EccPublicKeyToDer((ecc_key*)key->internal, buf, (word32)sz, 1);
        if (sz < 0) {
            WOLFSSL_MSG("wc_EccPublicKeyToDer failed");
            sz = 0;
        }
    }

    /* Return buffer on success. */
    if (sz > 0) {
        *der = buf;
    }
    else {
        /* Dispose of any dynamically allocated data not returned. */
        XFREE(buf, heap, DYNAMIC_TYPE_TMP_BUFFER);
    }

    return sz;
}
#endif

#if !defined(NO_FILESYSTEM) && defined(WOLFSSL_KEY_GEN)
/*
 * Return code compliant with OpenSSL.
 *
 * @param [in] fp   File pointer to write PEM encoding to.
 * @param [in] key  EC key to encode and write.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_PEM_write_EC_PUBKEY(XFILE fp, WOLFSSL_EC_KEY* key)
{
    int ret = 1;
    unsigned char* derBuf = NULL;
    int derSz = 0;

    WOLFSSL_ENTER("wolfSSL_PEM_write_EC_PUBKEY");

    /* Validate parameters. */
    if ((fp == XBADFILE) || (key == NULL)) {
        WOLFSSL_MSG("Bad argument.");
        return 0;
    }

    /* Encode public key in EC key as DER. */
    derSz = wolfssl_ec_key_to_pubkey_der(key, &derBuf, key->heap);
    if (derSz == 0) {
        ret = 0;
    }

    /* Write out to file the PEM encoding of the DER. */
    if ((ret == 1) && (der_write_to_file_as_pem(derBuf, derSz, fp,
            ECC_PUBLICKEY_TYPE, key->heap) != 1)) {
        ret = 0;
    }

    /* Dispose of any dynamically allocated data. */
    XFREE(derBuf, key->heap, DYNAMIC_TYPE_TMP_BUFFER);

    WOLFSSL_LEAVE("wolfSSL_PEM_write_EC_PUBKEY", ret);

    return ret;
}
#endif
#endif

#ifndef NO_BIO
/* Read a PEM encoded EC public key from a BIO.
 *
 * @param [in]  bio   BIO to read EC public key from.
 * @param [out] out   Pointer to return EC key object through. May be NULL.
 * @param [in]  cb    Password callback when PEM encrypted.
 * @param [in]  pass  NUL terminated string for passphrase when PEM
 *                    encrypted.
 * @return  New EC key object on success.
 * @return  NULL on error.
 */
WOLFSSL_EC_KEY* wolfSSL_PEM_read_bio_EC_PUBKEY(WOLFSSL_BIO* bio,
    WOLFSSL_EC_KEY** out, wc_pem_password_cb* cb, void *pass)
{
    int             err = 0;
    WOLFSSL_EC_KEY* ec = NULL;
    DerBuffer*      der = NULL;
    int             keyFormat = 0;

    WOLFSSL_ENTER("wolfSSL_PEM_read_bio_EC_PUBKEY");

    /* Validate parameters. */
    if (bio == NULL) {
        err = 1;
    }

    if (!err) {
        /* Create an empty EC key. */
        ec = wolfSSL_EC_KEY_new();
        if (ec == NULL) {
            err = 1;
        }
    }
    /* Read a PEM key in to a new DER buffer. */
    if ((!err) && (pem_read_bio_key(bio, cb, pass, ECC_PUBLICKEY_TYPE,
            &keyFormat, &der) <= 0)) {
        err = 1;
    }
    /* Load the EC key with the public key from the DER encoding. */
    if ((!err) && (wolfSSL_EC_KEY_LoadDer_ex(ec, der->buffer, (int)der->length,
            WOLFSSL_EC_KEY_LOAD_PUBLIC) != 1)) {
        WOLFSSL_ERROR_MSG("Error loading DER buffer into WOLFSSL_EC_KEY");
        err = 1;
    }

    /* Dispose of dynamically allocated data not needed anymore. */
    FreeDer(&der);
    if (err) {
        wolfSSL_EC_KEY_free(ec);
        ec = NULL;
    }

    /* Return EC key through out if required. */
    if ((out != NULL) && (ec != NULL)) {
        *out = ec;
    }
    return ec;
}

/* Read a PEM encoded EC private key from a BIO.
 *
 * @param [in]  bio   BIO to read EC private key from.
 * @param [out] out   Pointer to return EC key object through. May be NULL.
 * @param [in]  cb    Password callback when PEM encrypted.
 * @param [in]  pass  NUL terminated string for passphrase when PEM
 *                    encrypted.
 * @return  New EC key object on success.
 * @return  NULL on error.
 */
WOLFSSL_EC_KEY* wolfSSL_PEM_read_bio_ECPrivateKey(WOLFSSL_BIO* bio,
   WOLFSSL_EC_KEY** out, wc_pem_password_cb* cb, void *pass)
{
    int             err = 0;
    WOLFSSL_EC_KEY* ec = NULL;
    DerBuffer*      der = NULL;
    int             keyFormat = 0;

    WOLFSSL_ENTER("wolfSSL_PEM_read_bio_ECPrivateKey");

    /* Validate parameters. */
    if (bio == NULL) {
        err = 1;
    }

    if (!err) {
        /* Create an empty EC key. */
        ec = wolfSSL_EC_KEY_new();
        if (ec == NULL) {
            err = 1;
        }
    }
    /* Read a PEM key in to a new DER buffer.
     * To check ENC EC PRIVATE KEY, it uses PRIVATEKEY_TYPE to call
     * pem_read_bio_key(), and then check key format if it is EC.
     */
    if ((!err) && (pem_read_bio_key(bio, cb, pass, PRIVATEKEY_TYPE,
            &keyFormat, &der) <= 0)) {
        err = 1;
    }
    if (keyFormat != ECDSAk) {
        WOLFSSL_ERROR_MSG("Error not EC key format");
        err = 1;
    }
    /* Load the EC key with the private key from the DER encoding. */
    if ((!err) && (wolfSSL_EC_KEY_LoadDer_ex(ec, der->buffer, (int)der->length,
            WOLFSSL_EC_KEY_LOAD_PRIVATE) != 1)) {
        WOLFSSL_ERROR_MSG("Error loading DER buffer into WOLFSSL_EC_KEY");
        err = 1;
    }

    /* Dispose of dynamically allocated data not needed anymore. */
    FreeDer(&der);
    if (err) {
        wolfSSL_EC_KEY_free(ec);
        ec = NULL;
    }

    /* Return EC key through out if required. */
    if ((out != NULL) && (ec != NULL)) {
        *out = ec;
    }
    return ec;
}
#endif /* !NO_BIO */

#if defined(WOLFSSL_KEY_GEN) && defined(HAVE_ECC_KEY_EXPORT)
#ifndef NO_BIO
/* Write out the EC public key as PEM to the BIO.
 *
 * @param [in] bio  BIO to write PEM encoding to.
 * @param [in] ec   EC public key to encode.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_PEM_write_bio_EC_PUBKEY(WOLFSSL_BIO* bio, WOLFSSL_EC_KEY* ec)
{
    int ret = 1;
    unsigned char* derBuf = NULL;
    int derSz = 0;

    WOLFSSL_ENTER("wolfSSL_PEM_write_bio_EC_PUBKEY");

    /* Validate parameters. */
    if ((bio == NULL) || (ec == NULL)) {
        WOLFSSL_MSG("Bad Function Arguments");
        return 0;
    }

    /* Encode public key in EC key as DER. */
    derSz = wolfssl_ec_key_to_pubkey_der(ec, &derBuf, ec->heap);
    if (derSz == 0) {
        ret = 0;
    }

    /* Write out to BIO the PEM encoding of the EC public key. */
    if ((ret == 1) && (der_write_to_bio_as_pem(derBuf, derSz, bio,
            ECC_PUBLICKEY_TYPE) != 1)) {
        ret = 0;
    }

    /* Dispose of any dynamically allocated data. */
    XFREE(derBuf, ec->heap, DYNAMIC_TYPE_TMP_BUFFER);

    return ret;
}

/* Write out the EC private key as PEM to the BIO.
 *
 * Return code compliant with OpenSSL.
 *
 * @param [in] bio       BIO to write PEM encoding to.
 * @param [in] ec        EC private key to encode.
 * @param [in] cipher    Cipher to use when PEM encrypted. May be NULL.
 * @param [in] passwd    Password string when PEM encrypted. May be NULL.
 * @param [in] passwdSz  Length of password string when PEM encrypted.
 * @param [in] cb        Password callback when PEM encrypted. Unused.
 * @param [in] pass      NUL terminated string for passphrase when PEM
 *                       encrypted. Unused.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_PEM_write_bio_ECPrivateKey(WOLFSSL_BIO* bio, WOLFSSL_EC_KEY* ec,
    const EVP_CIPHER* cipher, unsigned char* passwd, int passwdSz,
    wc_pem_password_cb* cb, void* arg)
{
    int ret = 1;
    unsigned char* pem = NULL;
    int pLen = 0;

    (void)cb;
    (void)arg;

    /* Validate parameters. */
    if ((bio == NULL) || (ec == NULL)) {
        ret = 0;
    }

    /* Write EC private key to PEM. */
    if ((ret == 1) && (wolfSSL_PEM_write_mem_ECPrivateKey(ec, cipher, passwd,
            passwdSz, &pem, &pLen) != 1)) {
       ret = 0;
    }
    /* Write PEM to BIO. */
    if ((ret == 1) && (wolfSSL_BIO_write(bio, pem, pLen) != pLen)) {
        WOLFSSL_ERROR_MSG("EC private key BIO write failed");
        ret = 0;
    }

    XFREE(pem, NULL, DYNAMIC_TYPE_KEY);

    return ret;
}

#endif /* !NO_BIO */

/* Encode the EC private key as PEM into buffer.
 *
 * Return code compliant with OpenSSL.
 * Not an OpenSSL API.
 *
 * @param [in]  ec        EC private key to encode.
 * @param [in]  cipher    Cipher to use when PEM encrypted. May be NULL.
 * @param [in]  passwd    Password string when PEM encrypted. May be NULL.
 * @param [in]  passwdSz  Length of password string when PEM encrypted.
 * @param [out] pem       Newly allocated buffer holding PEM encoding.
 * @param [out] pLen      Length of PEM encoding in bytes.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_PEM_write_mem_ECPrivateKey(WOLFSSL_EC_KEY* ec,
    const EVP_CIPHER* cipher, unsigned char* passwd, int passwdSz,
    unsigned char **pem, int *pLen)
{
#if defined(WOLFSSL_PEM_TO_DER) || defined(WOLFSSL_DER_TO_PEM)
    int ret = 1;
    byte* derBuf = NULL;
    word32 der_max_len = 0;
    int derSz = 0;

    WOLFSSL_MSG("wolfSSL_PEM_write_mem_ECPrivateKey");

    /* Validate parameters. */
    if ((pem == NULL) || (pLen == NULL) || (ec == NULL) ||
            (ec->internal == NULL)) {
        WOLFSSL_MSG("Bad function arguments");
        ret = 0;
    }

    /* Ensure internal EC key is set from external. */
    if ((ret == 1) && (ec->inSet == 0)) {
        WOLFSSL_MSG("No ECC internal set, do it");

        if (SetECKeyInternal(ec) != 1) {
            WOLFSSL_MSG("SetECKeyInternal failed");
            ret = 0;
        }
    }

    if (ret == 1) {
        /* Calculate maximum size of DER encoding.
         * 4 > size of pub, priv + ASN.1 additional information */
        der_max_len = 4 * (word32)wc_ecc_size((ecc_key*)ec->internal) +
                      AES_BLOCK_SIZE;

        /* Allocate buffer big enough to hold encoding. */
        derBuf = (byte*)XMALLOC((size_t)der_max_len, NULL,
            DYNAMIC_TYPE_TMP_BUFFER);
        if (derBuf == NULL) {
            WOLFSSL_MSG("malloc failed");
            ret = 0;
        }
    }

    if (ret == 1) {
        /* Encode EC private key as DER. */
        derSz = wc_EccKeyToDer((ecc_key*)ec->internal, derBuf, der_max_len);
        if (derSz < 0) {
            WOLFSSL_MSG("wc_EccKeyToDer failed");
            XFREE(derBuf, NULL, DYNAMIC_TYPE_DER);
            ret = 0;
        }
    }

    /* Convert DER to PEM - possibly encrypting. */
    if ((ret == 1) && (der_to_enc_pem_alloc(derBuf, derSz, cipher, passwd,
            passwdSz, ECC_PRIVATEKEY_TYPE, NULL, pem, pLen) != 1)) {
        WOLFSSL_ERROR_MSG("der_to_enc_pem_alloc failed");
        ret = 0;
    }

    return ret;
#else
    (void)ec;
    (void)cipher;
    (void)passwd;
    (void)passwdSz;
    (void)pem;
    (void)pLen;
    return 0;
#endif /* WOLFSSL_PEM_TO_DER || WOLFSSL_DER_TO_PEM */
}

#ifndef NO_FILESYSTEM
/* Write out the EC private key as PEM to file.
 *
 * Return code compliant with OpenSSL.
 *
 * @param [in] fp        File pointer to write PEM encoding to.
 * @param [in] ec        EC private key to encode.
 * @param [in] cipher    Cipher to use when PEM encrypted. May be NULL.
 * @param [in] passwd    Password string when PEM encrypted. May be NULL.
 * @param [in] passwdSz  Length of password string when PEM encrypted.
 * @param [in] cb        Password callback when PEM encrypted. Unused.
 * @param [in] pass      NUL terminated string for passphrase when PEM
 *                       encrypted. Unused.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_PEM_write_ECPrivateKey(XFILE fp, WOLFSSL_EC_KEY *ec,
    const EVP_CIPHER *cipher, unsigned char *passwd, int passwdSz,
    wc_pem_password_cb *cb, void *pass)
{
    int ret = 1;
    byte *pem = NULL;
    int pLen = 0;

    (void)cb;
    (void)pass;

    WOLFSSL_MSG("wolfSSL_PEM_write_ECPrivateKey");

    /* Validate parameters. */
    if ((fp == XBADFILE) || (ec == NULL) || (ec->internal == NULL)) {
        WOLFSSL_MSG("Bad function arguments");
        ret = 0;
    }

    /* Write EC private key to PEM. */
    if ((ret == 1) && (wolfSSL_PEM_write_mem_ECPrivateKey(ec, cipher, passwd,
            passwdSz, &pem, &pLen) != 1)) {
        WOLFSSL_MSG("wolfSSL_PEM_write_mem_ECPrivateKey failed");
        ret = 0;
    }

    /* Write out to file the PEM encoding of the EC private key. */
    if ((ret == 1) && ((int)XFWRITE(pem, 1, (size_t)pLen, fp) != pLen)) {
        WOLFSSL_MSG("ECC private key file write failed");
        ret = 0;
    }

    /* Dispose of any dynamically allocated data. */
    XFREE(pem, NULL, DYNAMIC_TYPE_KEY);

    return ret;
}

#endif /* NO_FILESYSTEM */
#endif /* WOLFSSL_KEY_GEN && HAVE_ECC_KEY_EXPORT */

/*
 * EC key print APIs
 */

#ifndef NO_CERTS

#if defined(XFPRINTF) && !defined(NO_FILESYSTEM) && \
    !defined(NO_STDIO_FILESYSTEM)
/* Print the EC key to a file pointer as text.
 *
 * @param [in] fp      File pointer.
 * @param [in] key     EC key to print.
 * @param [in] indent  Number of spaces to place before each line printed.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_EC_KEY_print_fp(XFILE fp, WOLFSSL_EC_KEY* key, int indent)
{
    int ret = 1;
    int bits = 0;
    int priv = 0;

    WOLFSSL_ENTER("wolfSSL_EC_KEY_print_fp");

    /* Validate parameters. */
    if ((fp == XBADFILE) || (key == NULL) || (key->group == NULL) ||
            (indent < 0)) {
        ret = 0;
    }

    if (ret == 1) {
        /* Get EC groups order size in bits. */
        bits = wolfSSL_EC_GROUP_order_bits(key->group);
        if (bits <= 0) {
            WOLFSSL_MSG("Failed to get group order bits.");
            ret = 0;
        }
    }
    if (ret == 1) {
        const char* keyType;

        /* Determine whether this is a private or public key. */
        if ((key->priv_key != NULL) && (!wolfSSL_BN_is_zero(key->priv_key))) {
            keyType = "Private-Key";
            priv = 1;
        }
        else {
            keyType = "Public-Key";
        }

        /* Print key header. */
        if (XFPRINTF(fp, "%*s%s: (%d bit)\n", indent, "", keyType, bits) < 0) {
            ret = 0;
        }
    }
    if ((ret == 1) && priv) {
        /* Print the private key BN. */
        ret = pk_bn_field_print_fp(fp, indent, "priv", key->priv_key);
    }
    /* Check for public key data in EC key. */
    if ((ret == 1) && (key->pub_key != NULL) && (key->pub_key->exSet)) {
        /* Get the public key point as one BN. */
        WOLFSSL_BIGNUM* pubBn = wolfSSL_EC_POINT_point2bn(key->group,
            key->pub_key, POINT_CONVERSION_UNCOMPRESSED, NULL, NULL);
        if (pubBn == NULL) {
            WOLFSSL_MSG("wolfSSL_EC_POINT_point2bn failed.");
            ret = 0;
        }
        else {
            /* Print the public key in a BN. */
            ret = pk_bn_field_print_fp(fp, indent, "pub", pubBn);
            wolfSSL_BN_free(pubBn);
        }
    }
    if (ret == 1) {
        /* Get the NID of the group. */
        int nid = wolfSSL_EC_GROUP_get_curve_name(key->group);
        if (nid > 0) {
            /* Convert the NID into a long name and NIST name. */
            const char* curve = wolfSSL_OBJ_nid2ln(nid);
            const char* nistName = wolfSSL_EC_curve_nid2nist(nid);

            /* Print OID name if known. */
            if ((curve != NULL) &&
                (XFPRINTF(fp, "%*sASN1 OID: %s\n", indent, "", curve) < 0)) {
                ret = 0;
            }
            /* Print NIST curve name if known. */
            if ((nistName != NULL) &&
                (XFPRINTF(fp, "%*sNIST CURVE: %s\n", indent, "",
                    nistName) < 0)) {
                ret = 0;
            }
        }
    }


    WOLFSSL_LEAVE("wolfSSL_EC_KEY_print_fp", ret);

    return ret;
}
#endif /* XFPRINTF && !NO_FILESYSTEM && !NO_STDIO_FILESYSTEM */

#endif /* !NO_CERTS */

/*
 * EC_KEY get/set/test APIs
 */

/* Set data of internal, wolfCrypt EC key object into EC key.
 *
 * EC_KEY wolfSSL -> OpenSSL
 *
 * @param [in, out] p  EC key to update.
 * @return  1 on success.
 * @return  -1 on failure.
 */
int SetECKeyExternal(WOLFSSL_EC_KEY* eckey)
{
    int ret = 1;

    WOLFSSL_ENTER("SetECKeyExternal");

    /* Validate parameter. */
    if ((eckey == NULL) || (eckey->internal == NULL)) {
        WOLFSSL_MSG("ec key NULL error");
        ret = -1;
    }
    else {
        ecc_key* key = (ecc_key*)eckey->internal;

        /* Set group (OID, nid and idx) from wolfCrypt EC key. */
        eckey->group->curve_oid = (int)key->dp->oidSum;
        eckey->group->curve_nid = EccEnumToNID(key->dp->id);
        eckey->group->curve_idx = key->idx;

        if (eckey->pub_key->internal != NULL) {
            /* Copy internal public point from internal key's public point. */
            if (wc_ecc_copy_point(&key->pubkey,
                    (ecc_point*)eckey->pub_key->internal) != MP_OKAY) {
                WOLFSSL_MSG("SetECKeyExternal ecc_copy_point failed");
                ret = -1;
            }

            /* Set external public key from internal wolfCrypt, public key. */
            if ((ret == 1) && (ec_point_external_set(eckey->pub_key) != 1)) {
                WOLFSSL_MSG("SetECKeyExternal ec_point_external_set failed");
                ret = -1;
            }
        }

        /* set the external privkey */
        if ((ret == 1) && (key->type == ECC_PRIVATEKEY) &&
                (wolfssl_bn_set_value(&eckey->priv_key,
                wc_ecc_key_get_priv(key)) != 1)) {
            WOLFSSL_MSG("ec priv key error");
            ret = -1;
        }

        /* External values set when operations succeeded. */
        eckey->exSet = (ret == 1);
    }

    return ret;
}

/* Set data of EC key into internal, wolfCrypt EC key object.
 *
 * EC_KEY Openssl -> WolfSSL
 *
 * @param [in, out] p  EC key to update.
 * @return  1 on success.
 * @return  -1 on failure.
 */
int SetECKeyInternal(WOLFSSL_EC_KEY* eckey)
{
    int ret = 1;

    WOLFSSL_ENTER("SetECKeyInternal");

    /* Validate parameter. */
    if ((eckey == NULL) || (eckey->internal == NULL) ||
            (eckey->group == NULL)) {
        WOLFSSL_MSG("ec key NULL error");
        ret = -1;
    }
    else {
        ecc_key* key = (ecc_key*)eckey->internal;
        int pubSet = 0;

        /* Validate group. */
        if ((eckey->group->curve_idx < 0) ||
            (wc_ecc_is_valid_idx(eckey->group->curve_idx) == 0)) {
            WOLFSSL_MSG("invalid curve idx");
            ret = -1;
        }

        if (ret == 1) {
            /* Set group (idx of curve and corresponding domain parameters). */
            key->idx = eckey->group->curve_idx;
            key->dp = &ecc_sets[key->idx];
            pubSet = (eckey->pub_key != NULL);
        }
        /* Set public key (point). */
        if ((ret == 1) && pubSet) {
            if (ec_point_internal_set(eckey->pub_key) != 1) {
                WOLFSSL_MSG("ec key pub error");
                ret = -1;
            }
            /* Copy public point to key. */
            if ((ret == 1) && (wc_ecc_copy_point(
                    (ecc_point*)eckey->pub_key->internal, &key->pubkey) !=
                    MP_OKAY)) {
                WOLFSSL_MSG("wc_ecc_copy_point error");
                ret = -1;
            }

            if (ret == 1) {
                /* Set that the internal key is a public key */
                key->type = ECC_PUBLICKEY;
            }
        }

        /* set privkey */
        if ((ret == 1) && (eckey->priv_key != NULL)) {
            if (wolfssl_bn_get_value(eckey->priv_key,
                    wc_ecc_key_get_priv(key)) != 1) {
                WOLFSSL_MSG("ec key priv error");
                ret = -1;
            }
            /* private key */
            if ((ret == 1) && (!mp_iszero(wc_ecc_key_get_priv(key)))) {
                if (pubSet) {
                    key->type = ECC_PRIVATEKEY;
                }
                else {
                    key->type = ECC_PRIVATEKEY_ONLY;
                }
            }
        }

        /* Internal values set when operations succeeded. */
        eckey->inSet = (ret == 1);
    }

    return ret;
}

/* Get point conversion format of EC key.
 *
 * @param [in] key  EC key.
 * @return  Point conversion format on success.
 * @return  -1 on error.
 */
point_conversion_form_t wolfSSL_EC_KEY_get_conv_form(const WOLFSSL_EC_KEY* key)
{
    int ret = -1;

    if (key != NULL) {
        ret = key->form;
    }

    return ret;
}

/* Set point conversion format into EC key.
 *
 * @param [in, out] key   EC key to set format into.
 * @param [in]      form  Point conversion format. Valid values:
 *                          POINT_CONVERSION_UNCOMPRESSED,
 *                          POINT_CONVERSION_COMPRESSED (when HAVE_COMP_KEY)
 */
void wolfSSL_EC_KEY_set_conv_form(WOLFSSL_EC_KEY *key, int form)
{
    if (key == NULL) {
        WOLFSSL_MSG("Key passed in NULL");
    }
    else if (form == POINT_CONVERSION_UNCOMPRESSED
#ifdef HAVE_COMP_KEY
          || form == POINT_CONVERSION_COMPRESSED
#endif
             ) {
        key->form = (unsigned char)form;
    }
    else {
        WOLFSSL_MSG("Incorrect form or HAVE_COMP_KEY not compiled in");
    }
}

/* Get the EC group object that is in EC key.
 *
 * @param [in] key  EC key.
 * @return  EC group object on success.
 * @return  NULL when key is NULL.
 */
const WOLFSSL_EC_GROUP *wolfSSL_EC_KEY_get0_group(const WOLFSSL_EC_KEY *key)
{
    WOLFSSL_EC_GROUP* group = NULL;

    WOLFSSL_ENTER("wolfSSL_EC_KEY_get0_group");

    if (key != NULL) {
        group = key->group;
    }

    return group;
}

/* Set the group in WOLFSSL_EC_KEY
 *
 * @param [in, out] key    EC key to update.
 * @param [in]      group  EC group to copy.
 * @return  1 on success
 * @return  0 on failure.
 */
int wolfSSL_EC_KEY_set_group(WOLFSSL_EC_KEY *key, WOLFSSL_EC_GROUP *group)
{
    int ret = 1;

    WOLFSSL_ENTER("wolfSSL_EC_KEY_set_group");

    /* Validate parameters. */
    if ((key == NULL) || (group == NULL)) {
        ret = 0;
    }

    if (ret == 1) {
        /* Dispose of the current group. */
        if (key->group != NULL) {
            wolfSSL_EC_GROUP_free(key->group);
        }
        /* Duplicate the passed in group into EC key. */
        key->group = wolfSSL_EC_GROUP_dup(group);
        if (key->group == NULL) {
            ret = 0;
        }
    }

    return ret;
}

/* Get the BN object that is the private key in the EC key.
 *
 * @param [in] key  EC key.
 * @return  BN object on success.
 * @return  NULL when key is NULL or private key is not set.
 */
WOLFSSL_BIGNUM *wolfSSL_EC_KEY_get0_private_key(const WOLFSSL_EC_KEY *key)
{
    WOLFSSL_BIGNUM* priv_key = NULL;

    WOLFSSL_ENTER("wolfSSL_EC_KEY_get0_private_key");

    /* Validate parameter. */
    if (key == NULL) {
        WOLFSSL_MSG("wolfSSL_EC_KEY_get0_private_key Bad arguments");
    }
    /* Only return private key if it is not 0. */
    else if (!wolfSSL_BN_is_zero(key->priv_key)) {
        priv_key = key->priv_key;
    }

    return priv_key;
}

/* Sets the private key value into EC key.
 *
 * Return code compliant with OpenSSL.
 *
 * @param [in, out] key       EC key to set.
 * @param [in]      priv_key  Private key value in a BN.
 * @return  1 on success
 * @return  0 on failure.
 */
int wolfSSL_EC_KEY_set_private_key(WOLFSSL_EC_KEY *key,
    const WOLFSSL_BIGNUM *priv_key)
{
    int ret = 1;

    WOLFSSL_ENTER("wolfSSL_EC_KEY_set_private_key");

    /* Validate parameters. */
    if ((key == NULL) || (priv_key == NULL)) {
        WOLFSSL_MSG("Bad arguments");
        ret = 0;
    }

    /* Check for obvious invalid values. */
    if (wolfSSL_BN_is_negative(priv_key) || wolfSSL_BN_is_zero(priv_key) ||
            wolfSSL_BN_is_one(priv_key)) {
        WOLFSSL_MSG("Invalid private key value");
        ret = 0;
    }

    if (ret == 1) {
        /* Free key if previously set. */
        if (key->priv_key != NULL) {
            wolfSSL_BN_free(key->priv_key);
        }

        /* Duplicate the BN passed in. */
        key->priv_key = wolfSSL_BN_dup(priv_key);
        if (key->priv_key == NULL) {
            WOLFSSL_MSG("key ecc priv key NULL");
            ret = 0;
        }
    }
    /* Set the external values into internal EC key. */
    if ((ret == 1) && (SetECKeyInternal(key) != 1)) {
        WOLFSSL_MSG("SetECKeyInternal failed");
        /* Dispose of new private key on error. */
        wolfSSL_BN_free(key->priv_key);
        key->priv_key = NULL;
        ret = 0;
    }

    return ret;
}

/* Get the public key EC point object that is in EC key.
 *
 * @param [in] key  EC key.
 * @return  EC point object that is the public key on success.
 * @return  NULL when key is NULL.
 */
WOLFSSL_EC_POINT* wolfSSL_EC_KEY_get0_public_key(const WOLFSSL_EC_KEY *key)
{
    WOLFSSL_EC_POINT* pub_key = NULL;

    WOLFSSL_ENTER("wolfSSL_EC_KEY_get0_public_key");

    if (key != NULL) {
        pub_key = key->pub_key;
    }

    return pub_key;
}

/*
 * Return code compliant with OpenSSL.
 *
 * @param [in, out] key  EC key.
 * @param [in]      pub  Public key as an EC point.
 * @return  1 on success
 * @return  0 on failure.
 */
int wolfSSL_EC_KEY_set_public_key(WOLFSSL_EC_KEY *key,
    const WOLFSSL_EC_POINT *pub)
{
    int ret = 1;
    ecc_point *pub_p = NULL;
    ecc_point *key_p = NULL;

    WOLFSSL_ENTER("wolfSSL_EC_KEY_set_public_key");

    /* Validate parameters. */
    if ((key == NULL) || (key->internal == NULL) || (pub == NULL) ||
            (pub->internal == NULL)) {
        WOLFSSL_MSG("wolfSSL_EC_KEY_set_public_key Bad arguments");
        ret = 0;
    }

    /* Ensure the internal EC key is set. */
    if ((ret == 1) && (key->inSet == 0) && (SetECKeyInternal(key) != 1)) {
        WOLFSSL_MSG("SetECKeyInternal failed");
        ret = 0;
    }

    /* Ensure the internal EC point of pub is setup. */
    if ((ret == 1) && (ec_point_setup(pub) != 1)) {
        ret = 0;
    }

    if (ret == 1) {
        /* Get the internal point of pub and the public key in key. */
        pub_p = (ecc_point*)pub->internal;
        key_p = (ecc_point*)key->pub_key->internal;

        /* Create new point if required. */
        if (key_p == NULL) {
            key_p = wc_ecc_new_point();
            key->pub_key->internal = (void*)key_p;
        }
        /* Check point available. */
        if (key_p == NULL) {
            WOLFSSL_MSG("key ecc point NULL");
            ret = 0;
        }
    }

    /* Copy the internal pub point into internal key point. */
    if ((ret == 1) && (wc_ecc_copy_point(pub_p, key_p) != MP_OKAY)) {
        WOLFSSL_MSG("ecc_copy_point failure");
        ret = 0;
    }

    /* Copy the internal point data into external. */
    if ((ret == 1) && (ec_point_external_set(key->pub_key) != 1)) {
        WOLFSSL_MSG("SetECKeyInternal failed");
        ret = 0;
    }

    /* Copy the internal key into external. */
    if ((ret == 1) && (SetECKeyInternal(key) != 1)) {
        WOLFSSL_MSG("SetECKeyInternal failed");
        ret = 0;
    }

    if (ret == 1) {
        /* Dump out the point and the key's public key for debug. */
        wolfSSL_EC_POINT_dump("pub", pub);
        wolfSSL_EC_POINT_dump("key->pub_key", key->pub_key);
    }

    return ret;
}

#ifndef NO_WOLFSSL_STUB
/* Set the ASN.1 encoding flag against the EC key.
 *
 * No implementation as only named curves supported for encoding.
 *
 * @param [in, out] key   EC key.
 * @param [in]      flag  ASN.1 flag to set. Valid values:
 *                        OPENSSL_EC_EXPLICIT_CURVE, OPENSSL_EC_NAMED_CURVE
 */
void wolfSSL_EC_KEY_set_asn1_flag(WOLFSSL_EC_KEY *key, int asn1_flag)
{
    (void)key;
    (void)asn1_flag;

    WOLFSSL_ENTER("wolfSSL_EC_KEY_set_asn1_flag");
    WOLFSSL_STUB("EC_KEY_set_asn1_flag");
}
#endif

/*
 * EC key generate key APIs
 */

/* Generate an EC key.
 *
 * Uses the internal curve index set in the EC key or the default.
 *
 * @param [in, out] key  EC key.
 * @return  1 on success
 * @return  0 on failure.
 */
int wolfSSL_EC_KEY_generate_key(WOLFSSL_EC_KEY *key)
{
    int res = 1;
    int initTmpRng = 0;
    WC_RNG* rng = NULL;
#ifdef WOLFSSL_SMALL_STACK
    WC_RNG* tmpRng = NULL;
#else
    WC_RNG  tmpRng[1];
#endif

    WOLFSSL_ENTER("wolfSSL_EC_KEY_generate_key");

    /* Validate parameters. */
    if ((key == NULL) || (key->internal == NULL) || (key->group == NULL)) {
        WOLFSSL_MSG("wolfSSL_EC_KEY_generate_key Bad arguments");
        res = 0;
    }
    if (res == 1) {
        /* Check if we know which internal curve index to use. */
        if (key->group->curve_idx < 0) {
            /* Generate key using the default curve. */
#if FIPS_VERSION3_GE(6,0,0)
            key->group->curve_idx = ECC_SECP256R1; /* FIPS default to 256 */
#else
            key->group->curve_idx = ECC_CURVE_DEF;
#endif
        }

        /* Create a random number generator. */
        rng = wolfssl_make_rng(tmpRng, &initTmpRng);
        if (rng == NULL) {
            WOLFSSL_MSG("wolfSSL_EC_KEY_generate_key failed to make RNG");
            res = 0;
        }
    }
    if (res == 1) {
        /* NIDToEccEnum returns -1 for invalid NID so if key->group->curve_nid
         * is 0 then pass ECC_CURVE_DEF as arg */
        int eccEnum = key->group->curve_nid ?
#if FIPS_VERSION3_GE(6,0,0)
            NIDToEccEnum(key->group->curve_nid) : ECC_SECP256R1;
#else
            NIDToEccEnum(key->group->curve_nid) : ECC_CURVE_DEF;
#endif
        /* Get the internal EC key. */
        ecc_key* ecKey = (ecc_key*)key->internal;
        /* Make the key using internal API. */
        int ret = 0;

#if FIPS_VERSION3_GE(6,0,0)
        /* In the case of FIPS only allow key generation with approved curves */
        if (eccEnum != ECC_SECP256R1 && eccEnum != ECC_SECP224R1 &&
            eccEnum != ECC_SECP384R1 && eccEnum != ECC_SECP521R1) {
            WOLFSSL_MSG("Unsupported curve selected in FIPS mode");
            res = 0;
        }
        if (res == 1) {
#endif
        ret  = wc_ecc_make_key_ex(rng, 0, ecKey, eccEnum);
#if FIPS_VERSION3_GE(6,0,0)
        }
#endif

    #if defined(WOLFSSL_ASYNC_CRYPT)
        /* Wait on asynchronouse operation. */
        ret = wc_AsyncWait(ret, &ecKey->asyncDev, WC_ASYNC_FLAG_NONE);
    #endif
        if (ret != 0) {
            WOLFSSL_MSG("wolfSSL_EC_KEY_generate_key wc_ecc_make_key failed");
            res = 0;
        }
    }

    /* Dispose of local random number generator if initialized. */
    if (initTmpRng) {
        wc_FreeRng(rng);
    #ifdef WOLFSSL_SMALL_STACK
        XFREE(rng, NULL, DYNAMIC_TYPE_RNG);
    #endif
    }

    /* Set the external key from new internal key values. */
    if ((res == 1) && (SetECKeyExternal(key) != 1)) {
        WOLFSSL_MSG("wolfSSL_EC_KEY_generate_key SetECKeyExternal failed");
        res = 0;
    }

    return res;
}

/*
 * EC key check key APIs
 */

/* Check that the EC key is valid.
 *
 * @param [in] key  EC key.
 * @return  1 on valid.
 * @return  0 on invalid or error.
 */
int wolfSSL_EC_KEY_check_key(const WOLFSSL_EC_KEY *key)
{
    int ret = 1;

    WOLFSSL_ENTER("wolfSSL_EC_KEY_check_key");

    /* Validate parameter. */
    if ((key == NULL) || (key->internal == NULL)) {
        WOLFSSL_MSG("Bad parameter");
        ret = 0;
    }

    /* Set the external EC key values into internal if not already. */
    if ((ret == 1) && (key->inSet == 0) && (SetECKeyInternal(
            (WOLFSSL_EC_KEY*)key) != 1)) {
        WOLFSSL_MSG("SetECKeyInternal failed");
        ret = 0;
    }

    if (ret == 1) {
        /* Have internal EC implementation check key. */
        ret = wc_ecc_check_key((ecc_key*)key->internal) == 0;
    }

    return ret;
}

/* End EC_KEY */

#if !defined(HAVE_FIPS) || FIPS_VERSION_GT(2,0)
/* Get the supported, built-in EC curves
 *
 * @param [in, out] curves  Pre-allocated list to put supported curves into.
 * @param [in]      len     Maximum number of items to place in list.
 * @return  Number of built-in EC curves when curves is NULL or len is 0.
 * @return  Number of items placed in list otherwise.
 */
size_t wolfSSL_EC_get_builtin_curves(WOLFSSL_EC_BUILTIN_CURVE *curves,
    size_t len)
{
    size_t i;
    size_t cnt;
#ifdef HAVE_SELFTEST
    /* Defined in ecc.h when available. */
    size_t ecc_sets_count;

    /* Count the pre-defined curves since global not available. */
    for (i = 0; ecc_sets[i].size != 0 && ecc_sets[i].name != NULL; i++) {
        /* Do nothing. */
    }
    ecc_sets_count = i;
#endif

    /* Assume we are going to return total count. */
    cnt = ecc_sets_count;
    /* Check we have a list that can hold data. */
    if ((curves != NULL) && (len != 0)) {
        /* Limit count to length of list. */
        if (cnt > len) {
            cnt = len;
        }

        /* Put in built-in EC curve nid and short name. */
        for (i = 0; i < cnt; i++) {
            curves[i].nid = EccEnumToNID(ecc_sets[i].id);
            curves[i].comment = wolfSSL_OBJ_nid2sn(curves[i].nid);
        }
    }

    return cnt;
}
#endif /* !HAVE_FIPS || FIPS_VERSION_GT(2,0) */

/* Start ECDSA_SIG */

/* Allocate a new ECDSA signature object.
 *
 * @return  New, allocated ECDSA signature object on success.
 * @return  NULL on error.
 */
WOLFSSL_ECDSA_SIG *wolfSSL_ECDSA_SIG_new(void)
{
    int err = 0;
    WOLFSSL_ECDSA_SIG *sig;

    WOLFSSL_ENTER("wolfSSL_ECDSA_SIG_new");

    /* Allocate memory for ECDSA signature object. */
    sig = (WOLFSSL_ECDSA_SIG*)XMALLOC(sizeof(WOLFSSL_ECDSA_SIG), NULL,
        DYNAMIC_TYPE_ECC);
    if (sig == NULL) {
        WOLFSSL_MSG("wolfSSL_ECDSA_SIG_new malloc ECDSA signature failure");
        err = 1;
    }

    if (!err) {
        /* Set s to NULL in case of error. */
        sig->s = NULL;
        /* Allocate BN into r. */
        sig->r = wolfSSL_BN_new();
        if (sig->r == NULL) {
            WOLFSSL_MSG("wolfSSL_ECDSA_SIG_new malloc ECDSA r failure");
            err = 1;
        }
    }
    if (!err) {
        /* Allocate BN into s. */
        sig->s = wolfSSL_BN_new();
        if (sig->s == NULL) {
            WOLFSSL_MSG("wolfSSL_ECDSA_SIG_new malloc ECDSA s failure");
            err = 1;
        }
    }

    if (err && (sig != NULL)) {
        /* Dispose of allocated memory. */
        wolfSSL_ECDSA_SIG_free(sig);
        sig = NULL;
    }
    return sig;
}

/* Dispose of ECDSA signature object.
 *
 * Cannot use object after this call.
 *
 * @param [in] sig  ECDSA signature object to free.
 */
void wolfSSL_ECDSA_SIG_free(WOLFSSL_ECDSA_SIG *sig)
{
    WOLFSSL_ENTER("wolfSSL_ECDSA_SIG_free");

    if (sig != NULL) {
        /* Dispose of BNs allocated for r and s. */
        wolfSSL_BN_free(sig->r);
        wolfSSL_BN_free(sig->s);

        /* Dispose of memory associated with ECDSA signature object. */
        XFREE(sig, NULL, DYNAMIC_TYPE_ECC);
    }
}

/* Create an ECDSA signature from the DER encoding.
 *
 * @param [in, out] sig  Reference to ECDSA signature object. May be NULL.
 * @param [in, out] pp   On in, reference to buffer containing DER encoding.
 *                       On out, reference to buffer after signature data.
 * @param [in]      len  Length of the data in the buffer. May be more than
 *                       the length of the signature.
 * @return  ECDSA signature object on success.
 * @return  NULL on error.
 */
WOLFSSL_ECDSA_SIG* wolfSSL_d2i_ECDSA_SIG(WOLFSSL_ECDSA_SIG** sig,
    const unsigned char** pp, long len)
{
    int err = 0;
    /* ECDSA signature object to return. */
    WOLFSSL_ECDSA_SIG *s = NULL;

    /* Validate parameter. */
    if (pp == NULL) {
        err = 1;
    }
    if (!err) {
        if (sig != NULL) {
            /* Use the ECDSA signature object passed in. */
            s = *sig;
        }
        if (s == NULL) {
            /* No ECDSA signature object passed in - create a new one. */
            s = wolfSSL_ECDSA_SIG_new();
            if (s == NULL) {
                err = 1;
            }
        }
    }
    if (!err) {
        /* DecodeECC_DSA_Sig calls mp_init, so free these. */
        mp_free((mp_int*)s->r->internal);
        mp_free((mp_int*)s->s->internal);

        /* Decode the signature into internal r and s fields. */
        if (DecodeECC_DSA_Sig(*pp, (word32)len, (mp_int*)s->r->internal,
                (mp_int*)s->s->internal) != MP_OKAY) {
            err = 1;
        }
    }

    if (!err) {
        /* Move pointer passed signature data successfully decoded. */
        *pp += wolfssl_der_length(*pp, (int)len);
        if (sig != NULL) {
            /* Update reference to ECDSA signature object. */
            *sig = s;
        }
    }

    /* Dispose of newly allocated object on error. */
    if (err) {
        if ((s != NULL) && ((sig == NULL) || (*sig != s))) {
            wolfSSL_ECDSA_SIG_free(s);
        }
        /* Return NULL for object on error. */
        s = NULL;
    }
    return s;
}

/* Encode the ECDSA signature as DER.
 *
 * @param [in]      sig  ECDSA signature object.
 * @param [in, out] pp   On in, reference to buffer in which to place encoding.
 *                       On out, reference to buffer after encoding.
 *                       May be NULL or point to NULL in which case no encoding
 *                       is done.
 * @return  Length of encoding on success.
 * @return  0 on error.
 */
int wolfSSL_i2d_ECDSA_SIG(const WOLFSSL_ECDSA_SIG *sig, unsigned char **pp)
{
    word32 len = 0;
    int    update_p = 1;

    /* Validate parameter. */
    if (sig != NULL) {
        /* ASN.1: SEQ + INT + INT
         *   ASN.1 Integer must be a positive value - prepend zero if number has
         *   top bit set.
         */
        /* Get total length of r including any prepended zero. */
        word32 rLen = (word32)(mp_leading_bit((mp_int*)sig->r->internal) +
               mp_unsigned_bin_size((mp_int*)sig->r->internal));
        /* Get total length of s including any prepended zero. */
        word32 sLen = (word32)(mp_leading_bit((mp_int*)sig->s->internal) +
               mp_unsigned_bin_size((mp_int*)sig->s->internal));
        /* Calculate length of data in sequence. */
        len = (word32)1 + ASN_LEN_SIZE(rLen) + rLen +
              (word32)1 + ASN_LEN_SIZE(sLen) + sLen;
        /* Add in the length of the SEQUENCE. */
        len += (word32)1 + ASN_LEN_SIZE(len);

        #ifdef WOLFSSL_I2D_ECDSA_SIG_ALLOC
        if ((pp != NULL) && (*pp == NULL)) {
            *pp = (unsigned char *)XMALLOC(len, NULL, DYNAMIC_TYPE_OPENSSL);
            if (*pp != NULL) {
                WOLFSSL_MSG("malloc error");
                return 0;
            }
            update_p = 0;
        }
        #endif

        /* Encode only if there is a buffer to encode into. */
        if ((pp != NULL) && (*pp != NULL)) {
            /* Encode using the internal representations of r and s. */
            if (StoreECC_DSA_Sig(*pp, &len, (mp_int*)sig->r->internal,
                    (mp_int*)sig->s->internal) != MP_OKAY) {
                /* No bytes encoded. */
                len = 0;
            }
            else if (update_p) {
                /* Update pointer to after encoding. */
                *pp += len;
            }
        }
    }

    return (int)len;
}

/* Get the pointer to the fields of the ECDSA signature.
 *
 * r and s untouched when sig is NULL.
 *
 * @param [in]  sig  ECDSA signature object.
 * @param [out] r    R field of ECDSA signature as a BN. May be NULL.
 * @param [out] s    S field of ECDSA signature as a BN. May be NULL.
 */
void wolfSSL_ECDSA_SIG_get0(const WOLFSSL_ECDSA_SIG* sig,
    const WOLFSSL_BIGNUM** r, const WOLFSSL_BIGNUM** s)
{
    /* Validate parameter. */
    if (sig != NULL) {
        /* Return the r BN when pointer to return through. */
        if (r != NULL) {
            *r = sig->r;
        }
        /* Return the s BN when pointer to return through. */
        if (s != NULL) {
            *s = sig->s;
        }
    }
}

/* Set the pointers to the fields of the ECDSA signature.
 *
 * @param [in, out] sig  ECDSA signature object to update.
 * @param [in]      r    R field of ECDSA signature as a BN.
 * @param [in]      s    S field of ECDSA signature as a BN.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_ECDSA_SIG_set0(WOLFSSL_ECDSA_SIG* sig, WOLFSSL_BIGNUM* r,
    WOLFSSL_BIGNUM* s)
{
    int ret = 1;

    /* Validate parameters. */
    if ((sig == NULL) || (r == NULL) || (s == NULL)) {
        ret = 0;
    }

    if (ret == 1) {
        /* Dispose of old BN objects. */
        wolfSSL_BN_free(sig->r);
        wolfSSL_BN_free(sig->s);

        /* Assign new BN objects. */
        sig->r = r;
        sig->s = s;
    }

    return ret;
}

/* End ECDSA_SIG */

/* Start ECDSA */

/* Calculate maximum size of the DER encoded ECDSA signature for the curve.
 *
 * @param [in] key  EC key.
 * @return  Size of DER encoded signature on success.
 * @return  0 on error.
 */
int wolfSSL_ECDSA_size(const WOLFSSL_EC_KEY *key)
{
    int err = 0;
    int len = 0;
    const EC_GROUP *group = NULL;
    int bits = 0;

    /* Validate parameter. */
    if (key == NULL) {
        err = 1;
    }

    /* Get group from key to get order bits. */
    if ((!err) && ((group = wolfSSL_EC_KEY_get0_group(key)) == NULL)) {
        err = 1;
    }
    /* Get order bits of group. */
    if ((!err) && ((bits = wolfSSL_EC_GROUP_order_bits(group)) == 0)) {
        /* Group is not set. */
        err = 1;
    }

    if (!err) {
        /* r and s are mod order. */
        int bytes = (bits + 7) / 8;  /* Bytes needed to hold bits. */
        len = SIG_HEADER_SZ + /* 2*ASN_TAG + 2*LEN(ENUM) */
            ECC_MAX_PAD_SZ +  /* possible leading zeroes in r and s */
            bytes + bytes;    /* max r and s in bytes */
    }

    return len;
}

/* Create ECDSA signature by signing digest with key.
 *
 * @param [in] dgst  Digest to sign.
 * @param [in] dLen  Length of digest in bytes.
 * @param [in] key   EC key to sign with.
 * @return  ECDSA signature object on success.
 * @return  NULL on error.
 */
WOLFSSL_ECDSA_SIG *wolfSSL_ECDSA_do_sign(const unsigned char *dgst, int dLen,
    WOLFSSL_EC_KEY *key)
{
    int err = 0;
    WOLFSSL_ECDSA_SIG *sig = NULL;
#ifdef WOLFSSL_SMALL_STACK
    byte*   out = NULL;
#else
    byte    out[ECC_BUFSIZE];
#endif
    unsigned int outLen = ECC_BUFSIZE;

    WOLFSSL_ENTER("wolfSSL_ECDSA_do_sign");

    /* Validate parameters. */
    if ((dgst == NULL) || (key == NULL) || (key->internal == NULL)) {
        WOLFSSL_MSG("wolfSSL_ECDSA_do_sign Bad arguments");
        err = 1;
    }

    /* Ensure internal EC key is set from external. */
    if ((!err) && (key->inSet == 0)) {
        WOLFSSL_MSG("wolfSSL_ECDSA_do_sign No EC key internal set, do it");

        if (SetECKeyInternal(key) != 1) {
            WOLFSSL_MSG("wolfSSL_ECDSA_do_sign SetECKeyInternal failed");
            err = 1;
        }
    }

#ifdef WOLFSSL_SMALL_STACK
    if (!err) {
        /* Allocate buffer to hold encoded signature. */
        out = (byte*)XMALLOC(outLen, NULL, DYNAMIC_TYPE_TMP_BUFFER);
        if (out == NULL) {
            err = 1;
        }
    }
#endif

    /* Sign the digest with the key to create encoded ECDSA signature. */
    if ((!err) && (wolfSSL_ECDSA_sign(0, dgst, dLen, out, &outLen, key) != 1)) {
        err = 1;
    }

    if (!err) {
        const byte* p = out;
        /* Decode the ECDSA signature into a new object. */
        sig = wolfSSL_d2i_ECDSA_SIG(NULL, &p, outLen);
    }

#ifdef WOLFSSL_SMALL_STACK
    /* Dispose of any temporary dynamically allocated data. */
    XFREE(out, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif

    return sig;
}

/* Verify ECDSA signature in the object using digest and key.
 *
 * Return code compliant with OpenSSL.
 *
 * @param [in] dgst  Digest to verify.
 * @param [in] dLen  Length of the digest in bytes.
 * @param [in] sig   ECDSA signature object.
 * @param [in] key   EC key containing public key.
 * @return  1 when signature is valid.
 * @return  0 when signature is invalid.
 * @return  -1 on error.
 */
int wolfSSL_ECDSA_do_verify(const unsigned char *dgst, int dLen,
    const WOLFSSL_ECDSA_SIG *sig, WOLFSSL_EC_KEY *key)
{
    int ret = 1;
    int verified = 0;
#ifdef WOLF_CRYPTO_CB_ONLY_ECC
    byte signature[ECC_MAX_SIG_SIZE];
    int signatureLen;
    byte* p = signature;
#endif

    WOLFSSL_ENTER("wolfSSL_ECDSA_do_verify");

    /* Validate parameters. */
    if ((dgst == NULL) || (sig == NULL) || (key == NULL) ||
            (key->internal == NULL)) {
        WOLFSSL_MSG("wolfSSL_ECDSA_do_verify Bad arguments");
        ret = -1;
    }

    /* Ensure internal EC key is set from external. */
    if ((ret == 1) && (key->inSet == 0)) {
        WOLFSSL_MSG("No EC key internal set, do it");

        if (SetECKeyInternal(key) != 1) {
            WOLFSSL_MSG("SetECKeyInternal failed");
            ret = -1;
        }
    }

    if (ret == 1) {
#ifndef WOLF_CRYPTO_CB_ONLY_ECC
        /* Verify hash using digest, r and s as MP ints and internal EC key. */
        if (wc_ecc_verify_hash_ex((mp_int*)sig->r->internal,
                (mp_int*)sig->s->internal, dgst, (word32)dLen, &verified,
                (ecc_key *)key->internal) != MP_OKAY) {
            WOLFSSL_MSG("wc_ecc_verify_hash failed");
            ret = -1;
        }
        else if (verified == 0) {
            WOLFSSL_MSG("wc_ecc_verify_hash incorrect signature detected");
            ret = 0;
        }
#else
        signatureLen = i2d_ECDSA_SIG(sig, &p);
        if (signatureLen > 0) {
            /* verify hash. expects to call wc_CryptoCb_EccVerify internally */
            ret = wc_ecc_verify_hash(signature, signatureLen, dgst,
                (word32)dLen, &verified, (ecc_key*)key->internal);
            if (ret != MP_OKAY) {
                WOLFSSL_MSG("wc_ecc_verify_hash failed");
                ret = -1;
            }
            else if (verified == 0) {
                WOLFSSL_MSG("wc_ecc_verify_hash incorrect signature detected");
                ret = 0;
            }
        }
#endif /* WOLF_CRYPTO_CB_ONLY_ECC */
    }

    return ret;
}

/* Sign the digest with the key to produce a DER encode signature.
 *
 * @param [in]      type      Digest algorithm used to create digest. Unused.
 * @param [in]      digest    Digest of the message to sign.
 * @param [in]      digestSz  Size of the digest in bytes.
 * @param [out]     sig       Buffer to hold signature.
 * @param [in, out] sigSz     On in, size of buffer in bytes.
 *                            On out, size of signatre in bytes.
 * @param [in]      key       EC key containing private key.
 * @return  1 on success.
 * @return  0 on error.
 */
int wolfSSL_ECDSA_sign(int type, const unsigned char *digest, int digestSz,
    unsigned char *sig, unsigned int *sigSz, WOLFSSL_EC_KEY *key)
{
    int ret = 1;
    WC_RNG* rng = NULL;
#ifdef WOLFSSL_SMALL_STACK
    WC_RNG* tmpRng = NULL;
#else
    WC_RNG  tmpRng[1];
#endif
    int initTmpRng = 0;

    WOLFSSL_ENTER("wolfSSL_ECDSA_sign");

    /* Digest algorithm not used in DER encoding. */
    (void)type;

    /* Validate parameters. */
    if (key == NULL) {
        ret = 0;
    }

    if (ret == 1) {
        /* Make an RNG - create local or get global. */
        rng = wolfssl_make_rng(tmpRng, &initTmpRng);
        if (rng == NULL) {
            ret = 0;
        }
    }
    /* Sign the digest with the key using the RNG and put signature into buffer
     * update sigSz to be actual length.
     */
    if ((ret == 1) && (wc_ecc_sign_hash(digest, (word32)digestSz, sig, sigSz,
            rng, (ecc_key*)key->internal) != 0)) {
        ret = 0;
    }

    if (initTmpRng) {
        wc_FreeRng(rng);
    #ifdef WOLFSSL_SMALL_STACK
        XFREE(rng, NULL, DYNAMIC_TYPE_RNG);
    #endif
    }

    return ret;
}

/* Verify the signature with the digest and key.
 *
 * @param [in] type      Digest algorithm used to create digest. Unused.
 * @param [in] digest    Digest of the message to verify.
 * @param [in] digestSz  Size of the digest in bytes.
 * @param [in] sig       Buffer holding signature.
 * @param [in] sigSz     Size of signature data in bytes.
 * @param [in] key       EC key containing public key.
 * @return  1 when signature is valid.
 * @return  0 when signature is invalid or error.
 */
int wolfSSL_ECDSA_verify(int type, const unsigned char *digest, int digestSz,
    const unsigned char *sig, int sigSz, WOLFSSL_EC_KEY *key)
{
    int ret = 1;
    int verify = 0;

    WOLFSSL_ENTER("wolfSSL_ECDSA_verify");

    /* Digest algorithm not used in DER encoding. */
    (void)type;

    /* Validate parameters. */
    if (key == NULL) {
        ret = 0;
    }

    /* Verify signature using digest and key. */
    if ((ret == 1) && (wc_ecc_verify_hash(sig, (word32)sigSz, digest,
            (word32)digestSz, &verify, (ecc_key*)key->internal) != 0)) {
        ret = 0;
    }
    /* When no error, verification may still have failed - check now. */
    if ((ret == 1) && (verify != 1)) {
        WOLFSSL_MSG("wolfSSL_ECDSA_verify failed");
        ret = 0;
    }

    return ret;
}

/* End ECDSA */

/* Start ECDH */

#ifndef WOLF_CRYPTO_CB_ONLY_ECC
/* Compute the shared secret (key) using ECDH.
 *
 * KDF not supported.
 *
 * Return code compliant with OpenSSL.
 *
 * @param [out] out      Buffer to hold key.
 * @param [in]  outLen   Length of buffer in bytes.
 * @param [in]  pubKey   Public key as an EC point.
 * @param [in]  privKey  EC key holding a private key.
 * @param [in]  kdf      Key derivation function to apply to secret.
 * @return  Length of computed key on success
 * @return  0 on error.
 */
int wolfSSL_ECDH_compute_key(void *out, size_t outLen,
    const WOLFSSL_EC_POINT *pubKey, WOLFSSL_EC_KEY *privKey,
    void *(*kdf) (const void *in, size_t inlen, void *out, size_t *outLen))
{
    int err = 0;
    word32 len = 0;
    ecc_key* key = NULL;
#if defined(ECC_TIMING_RESISTANT) && !defined(HAVE_SELFTEST) && \
    (!defined(HAVE_FIPS) || FIPS_VERSION_GE(5,0))
    int setGlobalRNG = 0;
#endif

    /* TODO: support using the KDF. */
    (void)kdf;

    WOLFSSL_ENTER("wolfSSL_ECDH_compute_key");

    /* Validate parameters. */
    if ((out == NULL) || (pubKey == NULL) || (pubKey->internal == NULL) ||
        (privKey == NULL) || (privKey->internal == NULL)) {
        WOLFSSL_MSG("Bad function arguments");
        err = 1;
    }

    /* Ensure internal EC key is set from external. */
    if ((!err) && (privKey->inSet == 0)) {
        WOLFSSL_MSG("No EC key internal set, do it");

        if (SetECKeyInternal(privKey) != 1) {
            WOLFSSL_MSG("SetECKeyInternal failed");
            err = 1;
        }
    }

    if (!err) {
        int ret;

        /* Get the internal key. */
        key = (ecc_key*)privKey->internal;
        /* Set length into variable of type suitable for wolfSSL API. */
        len = (word32)outLen;

    #if defined(ECC_TIMING_RESISTANT) && !defined(HAVE_SELFTEST) && \
        (!defined(HAVE_FIPS) || FIPS_VERSION_GE(5,0))
        /* An RNG is needed. */
        if (key->rng == NULL) {
            key->rng = wolfssl_make_global_rng();
            /* RNG set and needs to be unset. */
            setGlobalRNG = 1;
        }
    #endif

        PRIVATE_KEY_UNLOCK();
        /* Create secret using wolfSSL. */
        ret = wc_ecc_shared_secret_ex(key, (ecc_point*)pubKey->internal,
            (byte *)out, &len);
        PRIVATE_KEY_LOCK();
        if (ret != MP_OKAY) {
            WOLFSSL_MSG("wc_ecc_shared_secret failed");
            err = 1;
        }
    }

#if defined(ECC_TIMING_RESISTANT) && !defined(HAVE_SELFTEST) && \
    (!defined(HAVE_FIPS) || FIPS_VERSION_GE(5,0))
    /* Remove global from key. */
    if (setGlobalRNG) {
        key->rng = NULL;
    }
#endif

    if (err) {
        /* Make returned value zero. */
        len = 0;
    }
    return (int)len;
}
#endif /* WOLF_CRYPTO_CB_ONLY_ECC */

/* End ECDH */

#ifndef NO_WOLFSSL_STUB
const WOLFSSL_EC_KEY_METHOD *wolfSSL_EC_KEY_OpenSSL(void)
{
    WOLFSSL_STUB("wolfSSL_EC_KEY_OpenSSL");

    return NULL;
}

WOLFSSL_EC_KEY_METHOD *wolfSSL_EC_KEY_METHOD_new(
        const WOLFSSL_EC_KEY_METHOD *meth)
{
    WOLFSSL_STUB("wolfSSL_EC_KEY_METHOD_new");

    (void)meth;

    return NULL;
}

void wolfSSL_EC_KEY_METHOD_free(WOLFSSL_EC_KEY_METHOD *meth)
{
    WOLFSSL_STUB("wolfSSL_EC_KEY_METHOD_free");

    (void)meth;
}

void wolfSSL_EC_KEY_METHOD_set_init(WOLFSSL_EC_KEY_METHOD *meth,
        void* a1, void* a2, void* a3, void* a4, void* a5, void* a6)
{
    WOLFSSL_STUB("wolfSSL_EC_KEY_METHOD_set_init");

    (void)meth;
    (void)a1;
    (void)a2;
    (void)a3;
    (void)a4;
    (void)a5;
    (void)a6;
}

void wolfSSL_EC_KEY_METHOD_set_sign(WOLFSSL_EC_KEY_METHOD *meth,
        void* a1, void* a2, void* a3)
{
    WOLFSSL_STUB("wolfSSL_EC_KEY_METHOD_set_sign");

    (void)meth;
    (void)a1;
    (void)a2;
    (void)a3;
}

const WOLFSSL_EC_KEY_METHOD *wolfSSL_EC_KEY_get_method(
        const WOLFSSL_EC_KEY *key)
{
    WOLFSSL_STUB("wolfSSL_EC_KEY_get_method");

    (void)key;

    return NULL;
}

int wolfSSL_EC_KEY_set_method(WOLFSSL_EC_KEY *key,
        const WOLFSSL_EC_KEY_METHOD *meth)
{
    WOLFSSL_STUB("wolfSSL_EC_KEY_set_method");

    (void)key;
    (void)meth;

    return 0;
}

#endif /* !NO_WOLFSSL_STUB */

#endif /* OPENSSL_EXTRA */

#endif /* HAVE_ECC */

/*******************************************************************************
 * END OF EC API
 ******************************************************************************/

/*******************************************************************************
 * START OF EC25519 API
 ******************************************************************************/

#if defined(OPENSSL_EXTRA) && defined(HAVE_CURVE25519)

/* Generate an EC25519 key pair.
 *
 * Output keys are in little endian format.
 *
 * @param [out]     priv    EC25519 private key data.
 * @param [in, out] privSz  On in, the size of priv in bytes.
 *                          On out, the length of the private key data in bytes.
 * @param [out]     pub     EC25519 public key data.
 * @param [in, out] pubSz   On in, the size of pub in bytes.
 *                          On out, the length of the public key data in bytes.
 * @return  1 on success
 * @return  0 on failure.
 */
int wolfSSL_EC25519_generate_key(unsigned char *priv, unsigned int *privSz,
    unsigned char *pub, unsigned int *pubSz)
{
#ifdef WOLFSSL_KEY_GEN
    int res = 1;
    int initTmpRng = 0;
    WC_RNG *rng = NULL;
#ifdef WOLFSSL_SMALL_STACK
    WC_RNG *tmpRng = NULL;
#else
    WC_RNG tmpRng[1];
#endif
    curve25519_key key;

    WOLFSSL_ENTER("wolfSSL_EC25519_generate_key");

    /* Validate parameters. */
    if ((priv == NULL) || (privSz == NULL) || (*privSz < CURVE25519_KEYSIZE) ||
            (pub == NULL) || (pubSz == NULL) || (*pubSz < CURVE25519_KEYSIZE)) {
        WOLFSSL_MSG("Bad arguments");
        res = 0;
    }

    if (res) {
        /* Create a random number generator. */
        rng = wolfssl_make_rng(tmpRng, &initTmpRng);
        if (rng == NULL) {
            WOLFSSL_MSG("wolfSSL_EC_KEY_generate_key failed to make RNG");
            res = 0;
        }
    }

    /* Initialize a Curve25519 key. */
    if (res && (wc_curve25519_init(&key) != 0)) {
        WOLFSSL_MSG("wc_curve25519_init failed");
        res = 0;
    }
    if (res) {
        /* Make a Curve25519 key pair. */
        int ret = wc_curve25519_make_key(rng, CURVE25519_KEYSIZE, &key);
        if (ret != MP_OKAY) {
            WOLFSSL_MSG("wc_curve25519_make_key failed");
            res = 0;
        }
        if (res) {
            /* Export Curve25519 key pair to buffers. */
            ret = wc_curve25519_export_key_raw_ex(&key, priv, privSz, pub,
                pubSz, EC25519_LITTLE_ENDIAN);
            if (ret != MP_OKAY) {
                WOLFSSL_MSG("wc_curve25519_export_key_raw_ex failed");
                res = 0;
            }
        }

        /* Dispose of key. */
        wc_curve25519_free(&key);
    }

    if (initTmpRng) {
        wc_FreeRng(rng);
    #ifdef WOLFSSL_SMALL_STACK
        XFREE(rng, NULL, DYNAMIC_TYPE_RNG);
    #endif
    }

    return res;
#else
    WOLFSSL_MSG("No Key Gen built in");

    (void)priv;
    (void)privSz;
    (void)pub;
    (void)pubSz;

    return 0;
#endif /* WOLFSSL_KEY_GEN */
}

/* Compute a shared secret from private and public EC25519 keys.
 *
 * Input and output keys are in little endian format
 *
 * @param [out]     shared    Shared secret buffer.
 * @param [in, out] sharedSz  On in, the size of shared in bytes.
 *                            On out, the length of the secret in bytes.
 * @param [in]      priv      EC25519 private key data.
 * @param [in]      privSz    Length of the private key data in bytes.
 * @param [in]      pub       EC25519 public key data.
 * @param [in]      pubSz     Length of the public key data in bytes.
 * @return  1 on success
 * @return  0 on failure.
 */
int wolfSSL_EC25519_shared_key(unsigned char *shared, unsigned int *sharedSz,
    const unsigned char *priv, unsigned int privSz, const unsigned char *pub,
    unsigned int pubSz)
{
#ifdef WOLFSSL_KEY_GEN
    int res = 1;
    curve25519_key privkey;
    curve25519_key pubkey;

    WOLFSSL_ENTER("wolfSSL_EC25519_shared_key");

    /* Validate parameters. */
    if ((shared == NULL) || (sharedSz == NULL) ||
            (*sharedSz < CURVE25519_KEYSIZE) || (priv == NULL) ||
            (privSz < CURVE25519_KEYSIZE) || (pub == NULL) ||
            (pubSz < CURVE25519_KEYSIZE)) {
        WOLFSSL_MSG("Bad arguments");
        res = 0;
    }

    /* Initialize private key object. */
    if (res && (wc_curve25519_init(&privkey) != 0)) {
        WOLFSSL_MSG("wc_curve25519_init privkey failed");
        res = 0;
    }
    if (res) {
        /* Initialize public key object. */
        if (wc_curve25519_init(&pubkey) != MP_OKAY) {
            WOLFSSL_MSG("wc_curve25519_init pubkey failed");
            res = 0;
        }
        if (res) {
            /* Import our private key. */
            int ret = wc_curve25519_import_private_ex(priv, privSz, &privkey,
                EC25519_LITTLE_ENDIAN);
            if (ret != 0) {
                WOLFSSL_MSG("wc_curve25519_import_private_ex failed");
                res = 0;
            }

            if (res) {
                /* Import peer's public key. */
                ret = wc_curve25519_import_public_ex(pub, pubSz, &pubkey,
                    EC25519_LITTLE_ENDIAN);
                if (ret != 0) {
                    WOLFSSL_MSG("wc_curve25519_import_public_ex failed");
                    res = 0;
                }
            }
            if (res) {
                /* Compute shared secret. */
                ret = wc_curve25519_shared_secret_ex(&privkey, &pubkey, shared,
                    sharedSz, EC25519_LITTLE_ENDIAN);
                if (ret != 0) {
                    WOLFSSL_MSG("wc_curve25519_shared_secret_ex failed");
                    res = 0;
                }
            }

            wc_curve25519_free(&pubkey);
        }
        wc_curve25519_free(&privkey);
    }

    return res;
#else
    WOLFSSL_MSG("No Key Gen built in");

    (void)shared;
    (void)sharedSz;
    (void)priv;
    (void)privSz;
    (void)pub;
    (void)pubSz;

    return 0;
#endif /* WOLFSSL_KEY_GEN */
}
#endif /* OPENSSL_EXTRA && HAVE_CURVE25519 */

/*******************************************************************************
 * END OF EC25519 API
 ******************************************************************************/

/*******************************************************************************
 * START OF ED25519 API
 ******************************************************************************/

#if defined(OPENSSL_EXTRA) && defined(HAVE_ED25519)
/* Generate an ED25519 key pair.
 *
 * Output keys are in little endian format.
 *
 * @param [out]     priv    ED25519 private key data.
 * @param [in, out] privSz  On in, the size of priv in bytes.
 *                          On out, the length of the private key data in bytes.
 * @param [out]     pub     ED25519 public key data.
 * @param [in, out] pubSz   On in, the size of pub in bytes.
 *                          On out, the length of the public key data in bytes.
 * @return  1 on success
 * @return  0 on failure.
 */
int wolfSSL_ED25519_generate_key(unsigned char *priv, unsigned int *privSz,
    unsigned char *pub, unsigned int *pubSz)
{
#if defined(WOLFSSL_KEY_GEN) && defined(HAVE_ED25519_KEY_EXPORT)
    int res = 1;
    int initTmpRng = 0;
    WC_RNG *rng = NULL;
#ifdef WOLFSSL_SMALL_STACK
    WC_RNG *tmpRng = NULL;
#else
    WC_RNG tmpRng[1];
#endif
    ed25519_key key;

    WOLFSSL_ENTER("wolfSSL_ED25519_generate_key");

    /* Validate parameters. */
    if ((priv == NULL) || (privSz == NULL) ||
            (*privSz < ED25519_PRV_KEY_SIZE) || (pub == NULL) ||
            (pubSz == NULL) || (*pubSz < ED25519_PUB_KEY_SIZE)) {
        WOLFSSL_MSG("Bad arguments");
        res = 0;
    }

    if (res) {
        /* Create a random number generator. */
        rng = wolfssl_make_rng(tmpRng, &initTmpRng);
        if (rng == NULL) {
            WOLFSSL_MSG("wolfSSL_EC_KEY_generate_key failed to make RNG");
            res = 0;
        }
    }

    /* Initialize an Ed25519 key. */
    if (res && (wc_ed25519_init(&key) != 0)) {
        WOLFSSL_MSG("wc_ed25519_init failed");
        res = 0;
    }
    if (res) {
        /* Make an Ed25519 key pair. */
        int ret = wc_ed25519_make_key(rng, ED25519_KEY_SIZE, &key);
        if (ret != 0) {
            WOLFSSL_MSG("wc_ed25519_make_key failed");
            res = 0;
        }
        if (res) {
            /* Export Curve25519 key pair to buffers. */
            ret = wc_ed25519_export_key(&key, priv, privSz, pub, pubSz);
            if (ret != 0) {
                WOLFSSL_MSG("wc_ed25519_export_key failed");
                res = 0;
            }
        }

        wc_ed25519_free(&key);
    }

    if (initTmpRng) {
        wc_FreeRng(rng);
    #ifdef WOLFSSL_SMALL_STACK
        XFREE(rng, NULL, DYNAMIC_TYPE_RNG);
    #endif
    }

    return res;
#else
#ifndef WOLFSSL_KEY_GEN
    WOLFSSL_MSG("No Key Gen built in");
#else
    WOLFSSL_MSG("No ED25519 key export built in");
#endif

    (void)priv;
    (void)privSz;
    (void)pub;
    (void)pubSz;

    return 0;
#endif /* WOLFSSL_KEY_GEN && HAVE_ED25519_KEY_EXPORT */
}

/* Sign a message with Ed25519 using the private key.
 *
 * Input and output keys are in little endian format.
 * Priv is a buffer containing private and public part of key.
 *
 * @param [in]      msg     Message to be signed.
 * @param [in]      msgSz   Length of message in bytes.
 * @param [in]      priv    ED25519 private key data.
 * @param [in]      privSz  Length in bytes of private key data.
 * @param [out]     sig     Signature buffer.
 * @param [in, out] sigSz   On in, the length of the signature buffer in bytes.
 *                          On out, the length of the signature in bytes.
 * @return  1 on success
 * @return  0 on failure.
 */
int wolfSSL_ED25519_sign(const unsigned char *msg, unsigned int msgSz,
    const unsigned char *priv, unsigned int privSz, unsigned char *sig,
    unsigned int *sigSz)
{
#if defined(HAVE_ED25519_SIGN) && defined(WOLFSSL_KEY_GEN) && \
    defined(HAVE_ED25519_KEY_IMPORT)
    ed25519_key key;
    int res = 1;

    WOLFSSL_ENTER("wolfSSL_ED25519_sign");

    /* Validate parameters. */
    if ((priv == NULL) || (privSz != ED25519_PRV_KEY_SIZE) ||
            (msg == NULL) || (sig == NULL) || (sigSz == NULL) ||
            (*sigSz < ED25519_SIG_SIZE)) {
        WOLFSSL_MSG("Bad arguments");
        res = 0;
    }

    /* Initialize Ed25519 key. */
    if (res && (wc_ed25519_init(&key) != 0)) {
        WOLFSSL_MSG("wc_curve25519_init failed");
        res = 0;
    }
    if (res) {
        /* Import private and public key. */
        int ret = wc_ed25519_import_private_key(priv, privSz / 2,
            priv + (privSz / 2), ED25519_PUB_KEY_SIZE, &key);
        if (ret != 0) {
            WOLFSSL_MSG("wc_ed25519_import_private failed");
            res = 0;
        }

        if (res) {
            /* Sign message with Ed25519. */
            ret = wc_ed25519_sign_msg(msg, msgSz, sig, sigSz, &key);
            if (ret != 0) {
                WOLFSSL_MSG("wc_curve25519_shared_secret_ex failed");
                res = 0;
            }
        }

        wc_ed25519_free(&key);
    }

    return res;
#else
#if !defined(HAVE_ED25519_SIGN)
    WOLFSSL_MSG("No ED25519 sign built in");
#elif !defined(WOLFSSL_KEY_GEN)
    WOLFSSL_MSG("No Key Gen built in");
#elif !defined(HAVE_ED25519_KEY_IMPORT)
    WOLFSSL_MSG("No ED25519 Key import built in");
#endif

    (void)msg;
    (void)msgSz;
    (void)priv;
    (void)privSz;
    (void)sig;
    (void)sigSz;

    return 0;
#endif /* HAVE_ED25519_SIGN && WOLFSSL_KEY_GEN && HAVE_ED25519_KEY_IMPORT */
}

/* Verify a message with Ed25519 using the public key.
 *
 * Input keys are in little endian format.
 *
 * @param [in] msg     Message to be verified.
 * @param [in] msgSz   Length of message in bytes.
 * @param [in] pub     ED25519 public key data.
 * @param [in] privSz  Length in bytes of public key data.
 * @param [in] sig     Signature buffer.
 * @param [in] sigSz   Length of the signature in bytes.
 * @return  1 on success
 * @return  0 on failure.
 */
int wolfSSL_ED25519_verify(const unsigned char *msg, unsigned int msgSz,
    const unsigned char *pub, unsigned int pubSz, const unsigned char *sig,
    unsigned int sigSz)
{
#if defined(HAVE_ED25519_VERIFY) && defined(WOLFSSL_KEY_GEN) && \
    defined(HAVE_ED25519_KEY_IMPORT)
    ed25519_key key;
    int res = 1;

    WOLFSSL_ENTER("wolfSSL_ED25519_verify");

    /* Validate parameters. */
    if ((pub == NULL) || (pubSz != ED25519_PUB_KEY_SIZE) || (msg == NULL) ||
            (sig == NULL) || (sigSz != ED25519_SIG_SIZE)) {
        WOLFSSL_MSG("Bad arguments");
        res = 0;
    }

    /* Initialize Ed25519 key. */
    if (res && (wc_ed25519_init(&key) != 0)) {
        WOLFSSL_MSG("wc_curve25519_init failed");
        res = 0;
    }
    if (res) {
        /* Import public key. */
        int ret = wc_ed25519_import_public(pub, pubSz, &key);
        if (ret != 0) {
            WOLFSSL_MSG("wc_ed25519_import_public failed");
            res = 0;
        }

        if (res) {
            int check = 0;

            /* Verify signature with message and public key. */
            ret = wc_ed25519_verify_msg((byte*)sig, sigSz, msg, msgSz, &check,
                &key);
            /* Check for errors in verification process. */
            if (ret != 0) {
                WOLFSSL_MSG("wc_ed25519_verify_msg failed");
                res = 0;
            }
            /* Check signature is valid. */
            else if (!check) {
                WOLFSSL_MSG("wc_ed25519_verify_msg failed (signature invalid)");
                res = 0;
            }
        }

        wc_ed25519_free(&key);
    }

    return res;
#else
#if !defined(HAVE_ED25519_VERIFY)
    WOLFSSL_MSG("No ED25519 verify built in");
#elif !defined(WOLFSSL_KEY_GEN)
    WOLFSSL_MSG("No Key Gen built in");
#elif !defined(HAVE_ED25519_KEY_IMPORT)
    WOLFSSL_MSG("No ED25519 Key import built in");
#endif

    (void)msg;
    (void)msgSz;
    (void)pub;
    (void)pubSz;
    (void)sig;
    (void)sigSz;

    return 0;
#endif /* HAVE_ED25519_VERIFY && WOLFSSL_KEY_GEN && HAVE_ED25519_KEY_IMPORT */
}

#endif /* OPENSSL_EXTRA && HAVE_ED25519 */

/*******************************************************************************
 * END OF ED25519 API
 ******************************************************************************/

/*******************************************************************************
 * START OF EC448 API
 ******************************************************************************/

#if defined(OPENSSL_EXTRA) && defined(HAVE_CURVE448)
/* Generate an EC448 key pair.
 *
 * Output keys are in little endian format.
 *
 * @param [out]     priv    EC448 private key data.
 * @param [in, out] privSz  On in, the size of priv in bytes.
 *                          On out, the length of the private key data in bytes.
 * @param [out]     pub     EC448 public key data.
 * @param [in, out] pubSz   On in, the size of pub in bytes.
 *                          On out, the length of the public key data in bytes.
 * @return  1 on success
 * @return  0 on failure.
 */
int wolfSSL_EC448_generate_key(unsigned char *priv, unsigned int *privSz,
                               unsigned char *pub, unsigned int *pubSz)
{
#ifdef WOLFSSL_KEY_GEN
    int res = 1;
    int initTmpRng = 0;
    WC_RNG *rng = NULL;
#ifdef WOLFSSL_SMALL_STACK
    WC_RNG *tmpRng = NULL;
#else
    WC_RNG tmpRng[1];
#endif
    curve448_key key;

    WOLFSSL_ENTER("wolfSSL_EC448_generate_key");

    /* Validate parameters. */
    if ((priv == NULL) || (privSz == NULL) || (*privSz < CURVE448_KEY_SIZE) ||
            (pub == NULL) || (pubSz == NULL) || (*pubSz < CURVE448_KEY_SIZE)) {
        WOLFSSL_MSG("Bad arguments");
        res = 0;
    }

    if (res) {
        /* Create a random number generator. */
        rng = wolfssl_make_rng(tmpRng, &initTmpRng);
        if (rng == NULL) {
            WOLFSSL_MSG("wolfSSL_EC_KEY_generate_key failed to make RNG");
            res = 0;
        }
    }

    /* Initialize a Curve448 key. */
    if (res && (wc_curve448_init(&key) != 0)) {
        WOLFSSL_MSG("wc_curve448_init failed");
        res = 0;
    }
    if (res) {
        /* Make a Curve448 key pair. */
        int ret = wc_curve448_make_key(rng, CURVE448_KEY_SIZE, &key);
        if (ret != 0) {
            WOLFSSL_MSG("wc_curve448_make_key failed");
            res = 0;
        }
        if (res) {
            /* Export Curve448 key pair to buffers. */
            ret = wc_curve448_export_key_raw_ex(&key, priv, privSz, pub, pubSz,
                EC448_LITTLE_ENDIAN);
            if (ret != 0) {
                WOLFSSL_MSG("wc_curve448_export_key_raw_ex failed");
                res = 0;
            }
        }

        /* Dispose of key. */
        wc_curve448_free(&key);
    }

    if (initTmpRng) {
        wc_FreeRng(rng);
    #ifdef WOLFSSL_SMALL_STACK
        XFREE(rng, NULL, DYNAMIC_TYPE_RNG);
    #endif
    }

    return res;
#else
    WOLFSSL_MSG("No Key Gen built in");

    (void)priv;
    (void)privSz;
    (void)pub;
    (void)pubSz;

    return 0;
#endif /* WOLFSSL_KEY_GEN */
}

/* Compute a shared secret from private and public EC448 keys.
 *
 * Input and output keys are in little endian format
 *
 * @param [out]     shared    Shared secret buffer.
 * @param [in, out] sharedSz  On in, the size of shared in bytes.
 *                            On out, the length of the secret in bytes.
 * @param [in]      priv      EC448 private key data.
 * @param [in]      privSz    Length of the private key data in bytes.
 * @param [in]      pub       EC448 public key data.
 * @param [in]      pubSz     Length of the public key data in bytes.
 * @return  1 on success
 * @return  0 on failure.
 */
int wolfSSL_EC448_shared_key(unsigned char *shared, unsigned int *sharedSz,
                             const unsigned char *priv, unsigned int privSz,
                             const unsigned char *pub, unsigned int pubSz)
{
#ifdef WOLFSSL_KEY_GEN
    int res = 1;
    curve448_key privkey;
    curve448_key pubkey;

    WOLFSSL_ENTER("wolfSSL_EC448_shared_key");

    /* Validate parameters. */
    if ((shared == NULL) || (sharedSz == NULL) ||
            (*sharedSz < CURVE448_KEY_SIZE) || (priv == NULL) ||
            (privSz < CURVE448_KEY_SIZE) || (pub == NULL) ||
            (pubSz < CURVE448_KEY_SIZE)) {
        WOLFSSL_MSG("Bad arguments");
        res = 0;
    }

    /* Initialize private key object. */
    if (res && (wc_curve448_init(&privkey) != 0)) {
        WOLFSSL_MSG("wc_curve448_init privkey failed");
        res = 0;
    }
    if (res) {
        /* Initialize public key object. */
        if (wc_curve448_init(&pubkey) != MP_OKAY) {
            WOLFSSL_MSG("wc_curve448_init pubkey failed");
            res = 0;
        }
        if (res) {
            /* Import our private key. */
            int ret = wc_curve448_import_private_ex(priv, privSz, &privkey,
                EC448_LITTLE_ENDIAN);
            if (ret != 0) {
                WOLFSSL_MSG("wc_curve448_import_private_ex failed");
                res = 0;
            }

            if (res) {
                /* Import peer's public key. */
                ret = wc_curve448_import_public_ex(pub, pubSz, &pubkey,
                    EC448_LITTLE_ENDIAN);
                if (ret != 0) {
                    WOLFSSL_MSG("wc_curve448_import_public_ex failed");
                    res = 0;
                }
            }
            if (res) {
                /* Compute shared secret. */
                ret = wc_curve448_shared_secret_ex(&privkey, &pubkey, shared,
                    sharedSz, EC448_LITTLE_ENDIAN);
                if (ret != 0) {
                    WOLFSSL_MSG("wc_curve448_shared_secret_ex failed");
                    res = 0;
                }
            }

            wc_curve448_free(&pubkey);
        }
        wc_curve448_free(&privkey);
    }

    return res;
#else
    WOLFSSL_MSG("No Key Gen built in");

    (void)shared;
    (void)sharedSz;
    (void)priv;
    (void)privSz;
    (void)pub;
    (void)pubSz;

    return 0;
#endif /* WOLFSSL_KEY_GEN */
}
#endif /* OPENSSL_EXTRA && HAVE_CURVE448 */

/*******************************************************************************
 * END OF EC448 API
 ******************************************************************************/

/*******************************************************************************
 * START OF ED448 API
 ******************************************************************************/

#if defined(OPENSSL_EXTRA) && defined(HAVE_ED448)
/* Generate an ED448 key pair.
 *
 * Output keys are in little endian format.
 *
 * @param [out]     priv    ED448 private key data.
 * @param [in, out] privSz  On in, the size of priv in bytes.
 *                          On out, the length of the private key data in bytes.
 * @param [out]     pub     ED448 public key data.
 * @param [in, out] pubSz   On in, the size of pub in bytes.
 *                          On out, the length of the public key data in bytes.
 * @return  1 on success
 * @return  0 on failure.
 */
int wolfSSL_ED448_generate_key(unsigned char *priv, unsigned int *privSz,
    unsigned char *pub, unsigned int *pubSz)
{
#if defined(WOLFSSL_KEY_GEN) && defined(HAVE_ED448_KEY_EXPORT)
    int res = 1;
    int initTmpRng = 0;
    WC_RNG *rng = NULL;
#ifdef WOLFSSL_SMALL_STACK
    WC_RNG *tmpRng = NULL;
#else
    WC_RNG tmpRng[1];
#endif
    ed448_key key;

    WOLFSSL_ENTER("wolfSSL_ED448_generate_key");

    /* Validate parameters. */
    if ((priv == NULL) || (privSz == NULL) ||
            (*privSz < ED448_PRV_KEY_SIZE) || (pub == NULL) ||
            (pubSz == NULL) || (*pubSz < ED448_PUB_KEY_SIZE)) {
        WOLFSSL_MSG("Bad arguments");
        res = 0;
    }

    if (res) {
        /* Create a random number generator. */
        rng = wolfssl_make_rng(tmpRng, &initTmpRng);
        if (rng == NULL) {
            WOLFSSL_MSG("wolfSSL_EC_KEY_generate_key failed to make RNG");
            res = 0;
        }
    }

    /* Initialize an Ed448 key. */
    if (res && (wc_ed448_init(&key) != 0)) {
        WOLFSSL_MSG("wc_ed448_init failed");
        res = 0;
    }
    if (res) {
        /* Make an Ed448 key pair. */
        int ret = wc_ed448_make_key(rng, ED448_KEY_SIZE, &key);
        if (ret != 0) {
            WOLFSSL_MSG("wc_ed448_make_key failed");
            res = 0;
        }
        if (res) {
            /* Export Curve448 key pair to buffers. */
            ret = wc_ed448_export_key(&key, priv, privSz, pub, pubSz);
            if (ret != 0) {
                WOLFSSL_MSG("wc_ed448_export_key failed");
                res = 0;
            }
        }

        wc_ed448_free(&key);
    }

    if (initTmpRng) {
        wc_FreeRng(rng);
    #ifdef WOLFSSL_SMALL_STACK
        XFREE(rng, NULL, DYNAMIC_TYPE_RNG);
    #endif
    }

    return res;
#else
#ifndef WOLFSSL_KEY_GEN
    WOLFSSL_MSG("No Key Gen built in");
#else
    WOLFSSL_MSG("No ED448 key export built in");
#endif

    (void)priv;
    (void)privSz;
    (void)pub;
    (void)pubSz;

    return 0;
#endif /* WOLFSSL_KEY_GEN && HAVE_ED448_KEY_EXPORT */
}

/* Sign a message with Ed448 using the private key.
 *
 * Input and output keys are in little endian format.
 * Priv is a buffer containing private and public part of key.
 *
 * @param [in]      msg     Message to be signed.
 * @param [in]      msgSz   Length of message in bytes.
 * @param [in]      priv    ED448 private key data.
 * @param [in]      privSz  Length in bytes of private key data.
 * @param [out]     sig     Signature buffer.
 * @param [in, out] sigSz   On in, the length of the signature buffer in bytes.
 *                          On out, the length of the signature in bytes.
 * @return  1 on success
 * @return  0 on failure.
 */
int wolfSSL_ED448_sign(const unsigned char *msg, unsigned int msgSz,
    const unsigned char *priv, unsigned int privSz, unsigned char *sig,
    unsigned int *sigSz)
{
#if defined(HAVE_ED448_SIGN) && defined(WOLFSSL_KEY_GEN) && \
    defined(HAVE_ED448_KEY_IMPORT)
    ed448_key key;
    int res = 1;

    WOLFSSL_ENTER("wolfSSL_ED448_sign");

    /* Validate parameters. */
    if ((priv == NULL) || (privSz != ED448_PRV_KEY_SIZE) ||
            (msg == NULL) || (sig == NULL) || (sigSz == NULL) ||
            (*sigSz < ED448_SIG_SIZE)) {
        WOLFSSL_MSG("Bad arguments");
        res = 0;
    }

    /* Initialize Ed448 key. */
    if (res && (wc_ed448_init(&key) != 0)) {
        WOLFSSL_MSG("wc_curve448_init failed");
        res = 0;
    }
    if (res) {
        /* Import private and public key. */
        int ret = wc_ed448_import_private_key(priv, privSz / 2,
            priv + (privSz / 2), ED448_PUB_KEY_SIZE, &key);
        if (ret != 0) {
            WOLFSSL_MSG("wc_ed448_import_private failed");
            res = 0;
        }

        if (res) {
            /* Sign message with Ed448 - no context. */
            ret = wc_ed448_sign_msg(msg, msgSz, sig, sigSz, &key, NULL, 0);
            if (ret != 0) {
                WOLFSSL_MSG("wc_curve448_shared_secret_ex failed");
                res = 0;
            }
        }

        wc_ed448_free(&key);
    }

    return res;
#else
#if !defined(HAVE_ED448_SIGN)
    WOLFSSL_MSG("No ED448 sign built in");
#elif !defined(WOLFSSL_KEY_GEN)
    WOLFSSL_MSG("No Key Gen built in");
#elif !defined(HAVE_ED448_KEY_IMPORT)
    WOLFSSL_MSG("No ED448 Key import built in");
#endif

    (void)msg;
    (void)msgSz;
    (void)priv;
    (void)privSz;
    (void)sig;
    (void)sigSz;

    return 0;
#endif /* HAVE_ED448_SIGN && WOLFSSL_KEY_GEN && HAVE_ED448_KEY_IMPORT */
}

/* Verify a message with Ed448 using the public key.
 *
 * Input keys are in little endian format.
 *
 * @param [in] msg     Message to be verified.
 * @param [in] msgSz   Length of message in bytes.
 * @param [in] pub     ED448 public key data.
 * @param [in] privSz  Length in bytes of public key data.
 * @param [in] sig     Signature buffer.
 * @param [in] sigSz   Length of the signature in bytes.
 * @return  1 on success
 * @return  0 on failure.
 */
int wolfSSL_ED448_verify(const unsigned char *msg, unsigned int msgSz,
    const unsigned char *pub, unsigned int pubSz, const unsigned char *sig,
    unsigned int sigSz)
{
#if defined(HAVE_ED448_VERIFY) && defined(WOLFSSL_KEY_GEN) && \
    defined(HAVE_ED448_KEY_IMPORT)
    ed448_key key;
    int res = 1;

    WOLFSSL_ENTER("wolfSSL_ED448_verify");

    /* Validate parameters. */
    if ((pub == NULL) || (pubSz != ED448_PUB_KEY_SIZE) || (msg == NULL) ||
            (sig == NULL) || (sigSz != ED448_SIG_SIZE)) {
        WOLFSSL_MSG("Bad arguments");
        res = 0;
    }

    /* Initialize Ed448 key. */
    if (res && (wc_ed448_init(&key) != 0)) {
        WOLFSSL_MSG("wc_curve448_init failed");
        res = 0;
    }
    if (res) {
        /* Import public key. */
        int ret = wc_ed448_import_public(pub, pubSz, &key);
        if (ret != 0) {
            WOLFSSL_MSG("wc_ed448_import_public failed");
            res = 0;
        }

        if (res) {
            int check = 0;

            /* Verify signature with message and public key - no context. */
            ret = wc_ed448_verify_msg((byte*)sig, sigSz, msg, msgSz, &check,
                &key, NULL, 0);
            /* Check for errors in verification process. */
            if (ret != 0) {
                WOLFSSL_MSG("wc_ed448_verify_msg failed");
                res = 0;
            }
            /* Check signature is valid. */
            else if (!check) {
                WOLFSSL_MSG("wc_ed448_verify_msg failed (signature invalid)");
                res = 0;
            }
        }

        wc_ed448_free(&key);
    }

    return res;
#else
#if !defined(HAVE_ED448_VERIFY)
    WOLFSSL_MSG("No ED448 verify built in");
#elif !defined(WOLFSSL_KEY_GEN)
    WOLFSSL_MSG("No Key Gen built in");
#elif !defined(HAVE_ED448_KEY_IMPORT)
    WOLFSSL_MSG("No ED448 Key import built in");
#endif

    (void)msg;
    (void)msgSz;
    (void)pub;
    (void)pubSz;
    (void)sig;
    (void)sigSz;

    return 0;
#endif /* HAVE_ED448_VERIFY && WOLFSSL_KEY_GEN && HAVE_ED448_KEY_IMPORT */
}
#endif /* OPENSSL_EXTRA && HAVE_ED448 */

/*******************************************************************************
 * END OF ED448 API
 ******************************************************************************/

/*******************************************************************************
 * START OF GENERIC PUBLIC KEY PEM APIs
 ******************************************************************************/

#ifdef OPENSSL_EXTRA
/* Sets default callback password for PEM.
 *
 * @param [out] buf       Buffer to hold password.
 * @param [in]  num       Number of characters in buffer.
 * @param [in]  rwFlag    Read/write flag. Ignored.
 * @param [in]  userData  User data - assumed to be default password.
 * @return  Password size on success.
 * @return  0 on failure.
 */
int wolfSSL_PEM_def_callback(char* buf, int num, int rwFlag, void* userData)
{
    int sz = 0;

    WOLFSSL_ENTER("wolfSSL_PEM_def_callback");

    (void)rwFlag;

    /* We assume that the user passes a default password as userdata */
    if ((buf != NULL) && (userData != NULL)) {
        sz = (int)XSTRLEN((const char*)userData);
        sz = (int)min((word32)sz, (word32)num);
        XMEMCPY(buf, userData, sz);
    }
    else {
        WOLFSSL_MSG("Error, default password cannot be created.");
    }

    return sz;
}

#ifndef NO_BIO
/* Writes a public key to a WOLFSSL_BIO encoded in PEM format.
 *
 * @param [in] bio  BIO to write to.
 * @param [in] key  Public key to write in PEM format.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_PEM_write_bio_PUBKEY(WOLFSSL_BIO* bio, WOLFSSL_EVP_PKEY* key)
{
    int ret = 0;

    WOLFSSL_ENTER("wolfSSL_PEM_write_bio_PUBKEY");

    if ((bio != NULL) && (key != NULL)) {
        switch (key->type) {
#if defined(WOLFSSL_KEY_GEN) && !defined(NO_RSA)
            case EVP_PKEY_RSA:
                ret = wolfSSL_PEM_write_bio_RSA_PUBKEY(bio, key->rsa);
                break;
#endif /* WOLFSSL_KEY_GEN && !NO_RSA */
#if !defined(NO_DSA) && !defined(HAVE_SELFTEST) && \
    (defined(WOLFSSL_KEY_GEN) || defined(WOLFSSL_CERT_GEN))
            case EVP_PKEY_DSA:
                ret = wolfSSL_PEM_write_bio_DSA_PUBKEY(bio, key->dsa);
                break;
#endif /* !NO_DSA && !HAVE_SELFTEST && (WOLFSSL_KEY_GEN || WOLFSSL_CERT_GEN) */
#if defined(HAVE_ECC) && defined(HAVE_ECC_KEY_EXPORT) && \
    defined(WOLFSSL_KEY_GEN)
            case EVP_PKEY_EC:
                ret = wolfSSL_PEM_write_bio_EC_PUBKEY(bio, key->ecc);
                break;
#endif /* HAVE_ECC && HAVE_ECC_KEY_EXPORT */
#if !defined(NO_DH) && (defined(WOLFSSL_QT) || defined(OPENSSL_ALL))
            case EVP_PKEY_DH:
                /* DH public key not supported. */
                WOLFSSL_MSG("Writing DH PUBKEY not supported!");
                break;
#endif /* !NO_DH && (WOLFSSL_QT || OPENSSL_ALL) */
            default:
                /* Key type not supported. */
                WOLFSSL_MSG("Unknown Key type!");
                break;
        }
    }

    return ret;
}

/* Writes a private key to a WOLFSSL_BIO encoded in PEM format.
 *
 * @param [in] bio     BIO to write to.
 * @param [in] key     Public key to write in PEM format.
 * @param [in] cipher  Encryption cipher to use.
 * @param [in] passwd  Password to use when encrypting.
 * @param [in] len     Length of password.
 * @param [in] cb      Password callback.
 * @param [in] arg     Password callback argument.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_PEM_write_bio_PrivateKey(WOLFSSL_BIO* bio, WOLFSSL_EVP_PKEY* key,
    const WOLFSSL_EVP_CIPHER* cipher, unsigned char* passwd, int len,
    wc_pem_password_cb* cb, void* arg)
{
    int ret = 1;

    WOLFSSL_ENTER("wolfSSL_PEM_write_bio_PrivateKey");

    (void)cipher;
    (void)passwd;
    (void)len;
    (void)cb;
    (void)arg;

    /* Validate parameters. */
    if ((bio == NULL) || (key == NULL)) {
        WOLFSSL_MSG("Bad Function Arguments");
        ret = 0;
    }

    if (ret == 1) {
    #ifdef WOLFSSL_KEY_GEN
        switch (key->type) {
        #ifndef NO_RSA
            case EVP_PKEY_RSA:
                /* Write using RSA specific API. */
                ret = wolfSSL_PEM_write_bio_RSAPrivateKey(bio, key->rsa,
                    cipher, passwd, len, cb, arg);
                break;
        #endif
        #ifndef NO_DSA
            case EVP_PKEY_DSA:
                /* Write using DSA specific API. */
                ret = wolfSSL_PEM_write_bio_DSAPrivateKey(bio, key->dsa,
                    cipher, passwd, len, cb, arg);
                break;
        #endif
        #ifdef HAVE_ECC
            case EVP_PKEY_EC:
            #if defined(HAVE_ECC_KEY_EXPORT)
                /* Write using EC specific API. */
                ret = wolfSSL_PEM_write_bio_ECPrivateKey(bio, key->ecc,
                    cipher, passwd, len, cb, arg);
            #else
                ret = der_write_to_bio_as_pem((byte*)key->pkey.ptr,
                    key->pkey_sz, bio, EC_PRIVATEKEY_TYPE);
            #endif
                break;
        #endif
        #ifndef NO_DH
            case EVP_PKEY_DH:
                /* Write using generic API with DH type. */
                ret = der_write_to_bio_as_pem((byte*)key->pkey.ptr,
                    key->pkey_sz, bio, DH_PRIVATEKEY_TYPE);
                break;
        #endif
            default:
                WOLFSSL_MSG("Unknown Key type!");
                ret = 0;
                break;
        }
    #else
        int type = 0;

        switch (key->type) {
        #ifndef NO_DSA
            case EVP_PKEY_DSA:
                type = DSA_PRIVATEKEY_TYPE;
                break;
        #endif
        #ifdef HAVE_ECC
            case EVP_PKEY_EC:
                type = ECC_PRIVATEKEY_TYPE;
                break;
        #endif
        #ifndef NO_DH
            case EVP_PKEY_DH:
                type = DH_PRIVATEKEY_TYPE;
                break;
        #endif
        #ifndef NO_RSA
            case EVP_PKEY_RSA:
                type = PRIVATEKEY_TYPE;
                break;
        #endif
            default:
                ret = 0;
                break;
        }
        if (ret == 1) {
            /* Write using generic API with generic type. */
            ret = der_write_to_bio_as_pem((byte*)key->pkey.ptr, key->pkey_sz,
                bio, type);
        }
    #endif
    }

    return ret;
}
#endif /* !NO_BIO */

#ifndef NO_BIO
/* Create a private key object from the data in the BIO.
 *
 * @param [in]      bio   BIO to read from.
 * @param [in, out] key   Public key object. Object used if passed in.
 * @param [in]      cb    Password callback.
 * @param [in]      arg   Password callback argument.
 * @return  A WOLFSSL_EVP_PKEY object on success.
 * @return  NULL on failure.
 */
WOLFSSL_EVP_PKEY* wolfSSL_PEM_read_bio_PUBKEY(WOLFSSL_BIO* bio,
    WOLFSSL_EVP_PKEY **key, wc_pem_password_cb *cb, void *arg)
{
    int err = 0;
    WOLFSSL_EVP_PKEY* pkey = NULL;
    DerBuffer* der = NULL;

    WOLFSSL_ENTER("wolfSSL_PEM_read_bio_PUBKEY");

    if (bio == NULL) {
        err = 1;
    }

    /* Read the PEM public key from the BIO and convert to DER. */
    if ((!err) && (pem_read_bio_key(bio, cb, arg, PUBLICKEY_TYPE, NULL,
            &der) < 0)) {
        err = 1;
    }

    if (!err) {
        const unsigned char* ptr = der->buffer;

        /* Use key passed in if set. */
        if ((key != NULL) && (*key != NULL)) {
            pkey = *key;
        }

        /* Convert DER data to a public key object. */
        if (wolfSSL_d2i_PUBKEY(&pkey, &ptr, der->length) == NULL) {
            WOLFSSL_MSG("Error loading DER buffer into WOLFSSL_EVP_PKEY");
            pkey = NULL;
            err = 1;
        }
    }

    /* Return the key if possible. */
    if ((!err) && (key != NULL) && (pkey != NULL)) {
        *key = pkey;
    }
    /* Dispose of the DER encoding. */
    FreeDer(&der);

    WOLFSSL_LEAVE("wolfSSL_PEM_read_bio_PUBKEY", 0);

    return pkey;
}

/* Create a private key object from the data in the BIO.
 *
 * @param [in]      bio   BIO to read from.
 * @param [in, out] key   Private key object. Object used if passed in.
 * @param [in]      cb    Password callback.
 * @param [in]      arg   Password callback argument.
 * @return  A WOLFSSL_EVP_PKEY object on success.
 * @return  NULL on failure.
 */
WOLFSSL_EVP_PKEY* wolfSSL_PEM_read_bio_PrivateKey(WOLFSSL_BIO* bio,
    WOLFSSL_EVP_PKEY** key, wc_pem_password_cb* cb, void* arg)
{
    int err = 0;
    WOLFSSL_EVP_PKEY* pkey = NULL;
    DerBuffer* der = NULL;
    int keyFormat = 0;

    WOLFSSL_ENTER("wolfSSL_PEM_read_bio_PrivateKey");

    /* Validate parameters. */
    if (bio == NULL) {
        err = 1;
    }

    /* Read the PEM private key from the BIO and convert to DER. */
    if ((!err) && (pem_read_bio_key(bio, cb, arg, PRIVATEKEY_TYPE, &keyFormat,
            &der) < 0)) {
        err = 1;
    }

    if (!err) {
        const unsigned char* ptr = der->buffer;
        int type = -1;

        /* Set key type based on format returned. */
        switch (keyFormat) {
            /* No key format set - default to RSA. */
            case 0:
            case RSAk:
                type = EVP_PKEY_RSA;
                break;
            case DSAk:
                type = EVP_PKEY_DSA;
                break;
            case ECDSAk:
                type = EVP_PKEY_EC;
                break;
            case DHk:
                type = EVP_PKEY_DH;
                break;
            default:
                break;
        }

        /* Use key passed in if set. */
        if ((key != NULL) && (*key != NULL)) {
            pkey = *key;
        }

        /* Convert DER data to a private key object. */
        if (wolfSSL_d2i_PrivateKey(type, &pkey, &ptr, der->length) == NULL) {
            WOLFSSL_MSG("Error loading DER buffer into WOLFSSL_EVP_PKEY");
            pkey = NULL;
            err = 1;
        }
    }

    /* Return the key if possible. */
    if ((!err) && (key != NULL) && (pkey != NULL)) {
        *key = pkey;
    }
    /* Dispose of the DER encoding. */
    FreeDer(&der);

    WOLFSSL_LEAVE("wolfSSL_PEM_read_bio_PrivateKey", err);

    return pkey;
}
#endif /* !NO_BIO */

#if !defined(NO_FILESYSTEM)
/* Create a private key object from the data in a file.
 *
 * @param [in]      fp    File pointer.
 * @param [in, out] key   Public key object. Object used if passed in.
 * @param [in]      cb    Password callback.
 * @param [in]      arg   Password callback argument.
 * @return  A WOLFSSL_EVP_PKEY object on success.
 * @return  NULL on failure.
 */
WOLFSSL_EVP_PKEY *wolfSSL_PEM_read_PUBKEY(XFILE fp, WOLFSSL_EVP_PKEY **key,
    wc_pem_password_cb *cb, void *arg)
{
    int err = 0;
    WOLFSSL_EVP_PKEY* pkey = NULL;
    DerBuffer* der = NULL;

    WOLFSSL_ENTER("wolfSSL_PEM_read_PUBKEY");

    /* Validate parameters. */
    if (fp == XBADFILE) {
        err = 1;
    }

    /* Read the PEM public key from the file and convert to DER. */
    if ((!err) && ((pem_read_file_key(fp, cb, arg, PUBLICKEY_TYPE, NULL,
            &der) < 0) || (der == NULL))) {
        err = 1;
    }
    if (!err) {
        const unsigned char* ptr = der->buffer;

        /* Use key passed in if set. */
        if ((key != NULL) && (*key != NULL)) {
            pkey = *key;
        }

        /* Convert DER data to a public key object. */
        if (wolfSSL_d2i_PUBKEY(&pkey, &ptr, der->length) == NULL) {
            WOLFSSL_MSG("Error loading DER buffer into WOLFSSL_EVP_PKEY");
            pkey = NULL;
            err = 1;
        }
    }

    /* Return the key if possible. */
    if ((!err) && (key != NULL) && (pkey != NULL)) {
        *key = pkey;
    }
    /* Dispose of the DER encoding. */
    FreeDer(&der);

    WOLFSSL_LEAVE("wolfSSL_PEM_read_PUBKEY", 0);

    return pkey;
}

#ifndef NO_CERTS
/* Create a private key object from the data in a file.
 *
 * @param [in]      fp    File pointer.
 * @param [in, out] key   Private key object. Object used if passed in.
 * @param [in]      cb    Password callback.
 * @param [in]      arg   Password callback argument.
 * @return  A WOLFSSL_EVP_PKEY object on success.
 * @return  NULL on failure.
 */
WOLFSSL_EVP_PKEY* wolfSSL_PEM_read_PrivateKey(XFILE fp, WOLFSSL_EVP_PKEY **key,
    wc_pem_password_cb *cb, void *arg)
{
    int err = 0;
    WOLFSSL_EVP_PKEY* pkey = NULL;
    DerBuffer* der = NULL;
    int keyFormat = 0;

    WOLFSSL_ENTER("wolfSSL_PEM_read_PrivateKey");

    /* Validate parameters. */
    if (fp == XBADFILE) {
        err = 1;
    }

    /* Read the PEM private key from the file and convert to DER. */
    if ((!err) && (pem_read_file_key(fp, cb, arg, PRIVATEKEY_TYPE, &keyFormat,
            &der)) < 0) {
        err = 1;
    }

    if (!err) {
        const unsigned char* ptr = der->buffer;
        int type = -1;

        /* Set key type based on format returned. */
        switch (keyFormat) {
            /* No key format set - default to RSA. */
            case 0:
            case RSAk:
                type = EVP_PKEY_RSA;
                break;
            case DSAk:
                type = EVP_PKEY_DSA;
                break;
            case ECDSAk:
                type = EVP_PKEY_EC;
                break;
            case DHk:
                type = EVP_PKEY_DH;
                break;
            default:
                break;
        }

        /* Use key passed in if set. */
        if ((key != NULL) && (*key != NULL)) {
            pkey = *key;
        }

        /* Convert DER data to a private key object. */
        if (wolfSSL_d2i_PrivateKey(type, &pkey, &ptr, der->length) == NULL) {
            WOLFSSL_MSG("Error loading DER buffer into WOLFSSL_EVP_PKEY");
            pkey = NULL;
            err = 1;
        }
    }

    /* Return the key if possible. */
    if ((!err) && (key != NULL) && (pkey != NULL)) {
        *key = pkey;
    }
    /* Dispose of the DER encoding. */
    FreeDer(&der);

    WOLFSSL_LEAVE("wolfSSL_PEM_read_PrivateKey", 0);

    return pkey;
}
#endif /* !NO_CERTS */
#endif /* !NO_FILESYSTEM */

#ifndef NO_CERTS

#if !defined(NO_BIO) || !defined(NO_FILESYSTEM)
#define PEM_BEGIN              "-----BEGIN "
#define PEM_BEGIN_SZ           11
#define PEM_END                "-----END "
#define PEM_END_SZ             9
#define PEM_HDR_FIN            "-----"
#define PEM_HDR_FIN_SZ         5
#define PEM_HDR_FIN_EOL_NEWLINE   "-----\n"
#define PEM_HDR_FIN_EOL_NULL_TERM "-----\0"
#define PEM_HDR_FIN_EOL_SZ     6

/* Find strings and return middle offsets.
 *
 * Find first string in pem as a prefix and then locate second string as a
 * postfix.
 * len returning with 0 indicates not found.
 *
 * @param [in]  pem      PEM data.
 * @param [in]  pemLen   Length of PEM data.
 * @param [in]  idx      Current index.
 * @param [in]  prefix   First string to find.
 * @param [in]  postfix  Second string to find after first.
 * @param [out] start    Start index of data between strings.
 * @param [out] len      Length of data between strings.
 */
static void pem_find_pattern(char* pem, int pemLen, int idx, const char* prefix,
    const char* postfix, int* start, int* len)
{
    int prefixLen = (int)XSTRLEN(prefix);
    int postfixLen = (int)XSTRLEN(postfix);

    *start = *len = 0;
    /* Find prefix part. */
    for (; idx < pemLen - prefixLen; idx++) {
        if ((pem[idx] == prefix[0]) &&
                (XMEMCMP(pem + idx, prefix, prefixLen) == 0)) {
            idx += prefixLen;
            *start = idx;
            break;
        }
    }
    /* Find postfix part. */
    for (; idx < pemLen - postfixLen; idx++) {
        if ((pem[idx] == postfix[0]) &&
                (XMEMCMP(pem + idx, postfix, postfixLen) == 0)) {
            *len = idx - *start;
            break;
        }
    }
}

/* Parse out content type name, any encryption headers and DER encoding.
 *
 * @param [in]  pem     PEM data.
 * @param [in]  pemLen  Length of PEM data.
 * @param [out] name    Name of content type.
 * @param [out] header  Encryption headers.
 * @param [out] data    DER encoding from PEM.
 * @param [out] len     Length of DER data.
 * @return  0 on success.
 * @return  MEMORY_E when dynamic memory allocation fails.
 * @return  ASN_NO_PEM_HEADER when no header found or different names found.
 */
static int pem_read_data(char* pem, int pemLen, char **name, char **header,
    unsigned char **data, long *len)
{
    int ret = 0;
    int start;
    int nameLen;
    int startHdr = 0;
    int hdrLen = 0;
    int startEnd = 0;
    int endLen;

    *name = NULL;
    *header = NULL;

    /* Find header. */
    pem_find_pattern(pem, pemLen, 0, PEM_BEGIN, PEM_HDR_FIN, &start, &nameLen);
    /* Allocate memory for header name. */
    *name = (char*)XMALLOC(nameLen + 1, NULL, DYNAMIC_TYPE_TMP_BUFFER);
    if (*name == NULL) {
        ret = MEMORY_E;
    }
    if (ret == 0) {
        /* Put in header name. */
        (*name)[nameLen] = '\0';
        if (nameLen == 0) {
            ret = ASN_NO_PEM_HEADER;
        }
        else {
            XMEMCPY(*name, pem + start, nameLen);
        }
    }
    if (ret == 0) {
        /* Find encryption headers after header. */
        start += nameLen + PEM_HDR_FIN_SZ;
        pem_find_pattern(pem, pemLen, start, "\n", "\n\n", &startHdr, &hdrLen);
        if (hdrLen > 0) {
            /* Include first of two '\n' characters. */
            hdrLen++;
        }
        /* Allocate memory for encryption header string. */
        *header = (char*)XMALLOC(hdrLen + 1, NULL, DYNAMIC_TYPE_TMP_BUFFER);
        if (*header == NULL) {
            ret = MEMORY_E;
        }
    }
    if (ret == 0) {
        /* Put in encryption header string. */
        (*header)[hdrLen] = '\0';
        if (hdrLen > 0) {
            XMEMCPY(*header, pem + startHdr, hdrLen);
            start = startHdr + hdrLen + 1;
        }

        /* Find footer. */
        pem_find_pattern(pem, pemLen, start, PEM_END, PEM_HDR_FIN, &startEnd,
            &endLen);
        /* Validate header name and footer name are the same. */
        if ((endLen != nameLen) ||
                 (XMEMCMP(*name, pem + startEnd, nameLen) != 0)) {
            ret = ASN_NO_PEM_HEADER;
        }
    }
    if (ret == 0) {
        unsigned char* der = (unsigned char*)pem;
        word32 derLen;

        /* Convert PEM body to DER. */
        derLen = (word32)(startEnd - PEM_END_SZ - start);
        ret = Base64_Decode(der + start, derLen, der, &derLen);
        if (ret == 0) {
            /* Return the DER data. */
            *data = der;
            *len = derLen;
        }
    }

    return ret;
}

/* Encode the DER data in PEM format into a newly allocated buffer.
 *
 * @param [in]  name       Header/footer name.
 * @param [in]  header     Encryption header.
 * @param [in]  data       DER data.
 * @param [in]  len        Length of DER data.
 * @param [out] pemOut     PEM encoded data.
 * @param [out] pemOutLen  Length of PEM encoded data.
 * @return  0 on success.
 * @return  MEMORY_E when dynamic memory allocation fails.
 */
static int pem_write_data(const char *name, const char *header,
    const unsigned char *data, long len, char** pemOut, word32* pemOutLen)
{
    int ret = 0;
    int nameLen;
    int headerLen;
    char* pem = NULL;
    word32 pemLen;
    word32 derLen = (word32)len;
    byte* p;

    nameLen = (int)XSTRLEN(name);
    headerLen = (int)XSTRLEN(header);

    /* DER encode for PEM. */
    pemLen  = (derLen + 2) / 3 * 4;
    pemLen += (pemLen + 63) / 64;
    /* Header */
    pemLen += PEM_BEGIN_SZ + nameLen + PEM_HDR_FIN_EOL_SZ;
    if (headerLen > 0) {
        /* Encryption lines plus extra carriage return. */
        pemLen += headerLen + 1;
    }
    /* Trailer */
    pemLen += PEM_END_SZ + nameLen + PEM_HDR_FIN_EOL_SZ;

    pem = (char*)XMALLOC(pemLen, NULL, DYNAMIC_TYPE_TMP_BUFFER);
    if (pem == NULL) {
        ret = MEMORY_E;
    }
    p = (byte*)pem;

    if (ret == 0) {
        /* Add header. */
        XMEMCPY(p, PEM_BEGIN, PEM_BEGIN_SZ);
        p += PEM_BEGIN_SZ;
        XMEMCPY(p, name, nameLen);
        p += nameLen;
        XMEMCPY(p, PEM_HDR_FIN_EOL_NEWLINE, PEM_HDR_FIN_EOL_SZ);
        p += PEM_HDR_FIN_EOL_SZ;

        if (headerLen > 0) {
            /* Add encryption header. */
            XMEMCPY(p, header, headerLen);
            p += headerLen;
            /* Blank line after a header and before body. */
            *(p++) = '\n';
        }

        /* Add DER data as PEM. */
        pemLen -= (word32)((size_t)p - (size_t)pem);
        ret = Base64_Encode(data, derLen, p, &pemLen);
    }
    if (ret == 0) {
        p += pemLen;

        /* Add trailer. */
        XMEMCPY(p, PEM_END, PEM_END_SZ);
        p += PEM_END_SZ;
        XMEMCPY(p, name, nameLen);
        p += nameLen;
        XMEMCPY(p, PEM_HDR_FIN_EOL_NEWLINE, PEM_HDR_FIN_EOL_SZ);
        p += PEM_HDR_FIN_EOL_SZ;

        /* Return buffer and length of data. */
        *pemOut = pem;
        *pemOutLen = (word32)((size_t)p - (size_t)pem);
    }

    return ret;
}
#endif /* !NO_BIO || !NO_FILESYSTEM */

#ifndef NO_BIO
/* Read PEM encoded data from a BIO.
 *
 * Reads the entire contents in.
 *
 * @param [in]  bio     BIO to read from.
 * @param [out] name    Name of content type.
 * @param [out] header  Encryption headers.
 * @param [out] data    DER encoding from PEM.
 * @param [out] len     Length of DER data.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_PEM_read_bio(WOLFSSL_BIO* bio, char **name, char **header,
    unsigned char **data, long *len)
{
    int res = 1;
    char* pem = NULL;
    int pemLen = 0;
    int memAlloced = 1;

    /* Validate parameters. */
    if ((bio == NULL) || (name == NULL) || (header == NULL) || (data == NULL) ||
            (len == NULL)) {
        res = 0;
    }

    /* Load all the data from the BIO. */
    if ((res == 1) && (wolfssl_read_bio(bio, &pem, &pemLen, &memAlloced) !=
             0)) {
        res = 0;
    }
    if ((res == 1) && (!memAlloced)) {
        /* Need to return allocated memory - make sure it is allocated. */
        char* p = (char*)XMALLOC(pemLen, NULL, DYNAMIC_TYPE_TMP_BUFFER);
        if (p == NULL) {
            res = 0;
        }
        else {
            /* Copy the data into new buffer. */
            XMEMCPY(p, pem, pemLen);
            pem = p;
        }
    }

    /* Read the PEM data. */
    if ((res == 1) && (pem_read_data(pem, pemLen, name, header, data, len) !=
            0)) {
        /* Dispose of any allocated memory. */
        XFREE(pem, NULL, DYNAMIC_TYPE_TMP_BUFFER);
        XFREE(*name, NULL, DYNAMIC_TYPE_TMP_BUFFER);
        XFREE(*header, NULL, DYNAMIC_TYPE_TMP_BUFFER);
        *name = NULL;
        *header = NULL;
        res = 0;
    }

    return res;
}

/* Encode the DER data in PEM format into a BIO.
 *
 * @param [in] bio     BIO to write to.
 * @param [in] name    Header/footer name.
 * @param [in] header  Encryption header.
 * @param [in] data    DER data.
 * @param [in] len     Length of DER data.
 * @return  0 on failure.
 */
int wolfSSL_PEM_write_bio(WOLFSSL_BIO* bio, const char *name,
    const char *header, const unsigned char *data, long len)
{
    int err = 0;
    char* pem = NULL;
    word32 pemLen = 0;

    /* Validate parameters. */
    if ((bio == NULL) || (name == NULL) || (header == NULL) || (data == NULL)) {
        err = BAD_FUNC_ARG;
    }

    /* Encode into a buffer. */
    if (!err) {
        err = pem_write_data(name, header, data, len, &pem, &pemLen);
    }

    /* Write PEM into BIO. */
    if ((!err) && (wolfSSL_BIO_write(bio, pem, (int)pemLen) != (int)pemLen)) {
        err = IO_FAILED_E;
    }

    XFREE(pem, NULL, DYNAMIC_TYPE_TMP_BUFFER);
    return (!err) ? pemLen : 0;
}
#endif /* !NO_BIO */

#if !defined(NO_FILESYSTEM)
/* Read PEM encoded data from a file.
 *
 * Reads the entire contents in.
 *
 * @param [in]  bio     BIO to read from.
 * @param [out] name    Name of content type.
 * @param [out] header  Encryption headers.
 * @param [out] data    DER encoding from PEM.
 * @param [out] len     Length of DER data.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_PEM_read(XFILE fp, char **name, char **header, unsigned char **data,
    long *len)
{
    int res = 1;
    char* pem = NULL;
    int pemLen = 0;

    /* Validate parameters. */
    if ((fp == XBADFILE) || (name == NULL) || (header == NULL) ||
            (data == NULL) || (len == NULL)) {
        res = 0;
    }

    /* Load all the data from the file. */
    if ((res == 1) && (wolfssl_read_file(fp, &pem, &pemLen) != 0)) {
        res = 0;
    }

    /* Read the PEM data. */
    if ((res == 1) && (pem_read_data(pem, pemLen, name, header, data, len) !=
            0)) {
        /* Dispose of any allocated memory. */
        XFREE(pem, NULL, DYNAMIC_TYPE_TMP_BUFFER);
        XFREE(*name, NULL, DYNAMIC_TYPE_TMP_BUFFER);
        XFREE(*header, NULL, DYNAMIC_TYPE_TMP_BUFFER);
        *name = NULL;
        *header = NULL;
        res = 0;
    }

    return res;
}

/* Encode the DER data in PEM format into a file.
 *
 * @param [in] fp      File pointer to write to.
 * @param [in] name    Header/footer name.
 * @param [in] header  Encryption header.
 * @param [in] data    DER data.
 * @param [in] len     Length of DER data.
 * @return  0 on success.
 * @return  MEMORY_E when dynamic memory allocation fails.
 */
int wolfSSL_PEM_write(XFILE fp, const char *name, const char *header,
    const unsigned char *data, long len)
{
    int err = 0;
    char* pem = NULL;
    word32 pemLen = 0;

    /* Validate parameters. */
    if ((fp == XBADFILE) || (name == NULL) || (header == NULL) ||
            (data == NULL)) {
        err = 1;
    }

    /* Encode into a buffer. */
    if ((!err) && (pem_write_data(name, header, data, len, &pem, &pemLen) !=
            0)) {
        pemLen = 0;
        err = 1;
    }

    /* Write PEM to a file. */
    if ((!err) && (XFWRITE(pem, 1, pemLen, fp) != pemLen)) {
        pemLen = 0;
    }

    XFREE(pem, NULL, DYNAMIC_TYPE_TMP_BUFFER);
    return (int)pemLen;
}
#endif

/* Get EVP cipher info from encryption header string.
 *
 * @param [in]  header  Encryption header.
 * @param [out] cipher  EVP Cipher info.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_PEM_get_EVP_CIPHER_INFO(const char* header, EncryptedInfo* cipher)
{
    int res = 1;

    /* Validate parameters. */
    if ((header == NULL) || (cipher == NULL)) {
        res = 0;
    }

    if (res == 1) {
        XMEMSET(cipher, 0, sizeof(*cipher));

        if (wc_EncryptedInfoParse(cipher, &header, XSTRLEN(header)) != 0) {
            res = 0;
        }
    }

    return res;
}

/* Apply cipher to DER data.
 *
 * @param [in]      cipher  EVP cipher info.
 * @param [in, out] data    On in, encrypted DER data.
 *                          On out, unencrypted DER data.
 * @param [in, out] len     On in, length of encrypted DER data.
 *                          On out, length of unencrypted DER data.
 * @param [in]      cb      Password callback.
 * @param [in]      ctx     Context for password callback.
 * @return  1 on success.
 * @return  0 on failure.
 */
int wolfSSL_PEM_do_header(EncryptedInfo* cipher, unsigned char* data, long* len,
    wc_pem_password_cb* cb, void* ctx)
{
    int ret = 1;
    char password[NAME_SZ];
    int passwordSz = 0;

    /* Validate parameters. */
    if ((cipher == NULL) || (data == NULL) || (len == NULL) || (cb == NULL)) {
        ret = 0;
    }

    if (ret == 1) {
        /* Get password and length. */
        passwordSz = cb(password, sizeof(password), PEM_PASS_READ, ctx);
        if (passwordSz < 0) {
            ret = 0;
        }
    }

    if (ret == 1) {
        /* Decrypt the data using password and MD5. */
        if (wc_BufferKeyDecrypt(cipher, data, (word32)*len, (byte*)password,
                passwordSz, WC_MD5) != 0) {
            ret = WOLFSSL_FAILURE;
        }
    }

    if (passwordSz > 0) {
        /* Ensure password is erased from memory. */
        ForceZero(password, (word32)passwordSz);
    }

    return ret;
}

#endif /* !NO_CERTS */
#endif /* OPENSSL_EXTRA */

#ifdef OPENSSL_ALL
#if !defined(NO_PWDBASED) && defined(HAVE_PKCS8)

#if !defined(NO_BIO) || (!defined(NO_FILESYSTEM) && \
    !defined(NO_STDIO_FILESYSTEM))
/* Encrypt the key into a buffer using PKCS$8 and a password.
 *
 * @param [in]      pkey      Private key to encrypt.
 * @param [in]      enc       EVP cipher.
 * @param [in]      passwd    Password to encrypt with.
 * @param [in]      passwdSz  Number of bytes in password.
 * @param [in]      key       Buffer to hold encrypted key.
 * @param [in, out] keySz     On in, size of buffer in bytes.
 *                            On out, size of encrypted key in bytes.
 * @return  0 on success.
 * @return  BAD_FUNC_ARG when EVP cipher not supported.
 */
static int pem_pkcs8_encrypt(WOLFSSL_EVP_PKEY* pkey,
    const WOLFSSL_EVP_CIPHER* enc, char* passwd, int passwdSz, byte* key,
    word32* keySz)
{
    int ret;
    WC_RNG rng;

    /* Initialize a new random number generator. */
    ret = wc_InitRng(&rng);
    if (ret == 0) {
        int encAlgId = 0;

        /* Convert EVP cipher to a support encryption id. */
    #ifndef NO_DES3
        if (enc == EVP_DES_CBC) {
            encAlgId = DESb;
        }
        else if (enc == EVP_DES_EDE3_CBC) {
            encAlgId = DES3b;
        }
        else
    #endif
#if !defined(NO_AES) && defined(HAVE_AES_CBC)
    #ifdef WOLFSSL_AES_128
        if (enc == EVP_AES_128_CBC) {
            encAlgId = AES128CBCb;
        }
        else
     #endif
    #ifdef WOLFSSL_AES_256
        if (enc == EVP_AES_256_CBC) {
            encAlgId = AES256CBCb;
        }
        else
     #endif
#endif
        {
            ret = BAD_FUNC_ARG;
        }

        if (ret == 0) {
            /* Encrypt private into buffer. */
            ret = TraditionalEnc((byte*)pkey->pkey.ptr, pkey->pkey_sz,
                key, keySz, passwd, passwdSz, PKCS5, PBES2, encAlgId,
                NULL, 0, WC_PKCS12_ITT_DEFAULT, &rng, NULL);
            if (ret > 0) {
                *keySz = (word32)ret;
            }
        }
        /* Dispose of random number generator. */
        wc_FreeRng(&rng);
    }

    return ret;
}

/* Encode private key in PKCS#8 format.
 *
 * @param [in]      pkey   Private key.
 * @param [out]     key    Buffer to hold encoding.
 * @param [in, out] keySz  On in, size of buffer in bytes.
 * @param                  On out, size of encoded key in bytes.
 * @return  0 on success.
 */
static int pem_pkcs8_encode(WOLFSSL_EVP_PKEY* pkey, byte* key, word32* keySz)
{
    int ret = 0;
    int algId;
    const byte* curveOid;
    word32 oidSz;

    /* Get the details of the private key. */
#ifdef HAVE_ECC
    if (pkey->type == EVP_PKEY_EC) {
        /* ECC private and get curve OID information. */
        algId = ECDSAk;
        ret = wc_ecc_get_oid(pkey->ecc->group->curve_oid, &curveOid,
            &oidSz);
    }
    else
#endif
    if (pkey->type == EVP_PKEY_RSA) {
        /* RSA private has no curve information. */
        algId = RSAk;
        curveOid = NULL;
        oidSz = 0;
    }
    else {
        ret = NOT_COMPILED_IN;
    }

    if (ret >= 0) {
        /* Encode private key in PKCS#8 format. */
        ret = wc_CreatePKCS8Key(key, keySz, (byte*)pkey->pkey.ptr,
            pkey->pkey_sz, algId, curveOid, oidSz);
    }

    return ret;
}

/* Write PEM encoded, PKCS#8 formatted private key to BIO.
 *
 * @param [out] pem       Buffer holding PEM encoding.
 * @param [out] pemSz     Size of data in buffer in bytes.
 * @param [in]  pkey      Private key to write.
 * @param [in]  enc       Encryption information to use. May be NULL.
 * @param [in]  passwd    Password to use when encrypting. May be NULL.
 * @param [in]  passwdSz  Size of password in bytes.
 * @param [in]  cb        Password callback. Used when passwd is NULL. May be
 *                        NULL.
 * @param [in]  ctx       Context for password callback.
 * @return  Length of PEM encoding on success.
 * @return  0 on failure.
 */
static int pem_write_mem_pkcs8privatekey(byte** pem, int* pemSz,
    WOLFSSL_EVP_PKEY* pkey, const WOLFSSL_EVP_CIPHER* enc, char* passwd,
    int passwdSz, wc_pem_password_cb* cb, void* ctx)
{
    int res = 1;
    int ret = 0;
    char password[NAME_SZ];
    byte* key = NULL;
    word32 keySz;
    int type = PKCS8_PRIVATEKEY_TYPE;

    /* Validate parameters. */
    if (pkey == NULL) {
        res = 0;
    }

    if (res == 1) {
        /* Guestimate key size and PEM size. */
        if (pem_pkcs8_encode(pkey, NULL, &keySz) != WC_NO_ERR_TRACE(LENGTH_ONLY_E)) {
            res = 0;
        }
    }
    if (res == 1) {
        if (enc != NULL) {
            /* Add on enough for extra DER data when encrypting. */
            keySz += 128;
        }
        /* PEM encoding size from DER size. */
        *pemSz  = (int)(keySz + 2) / 3 * 4;
        *pemSz += (*pemSz + 63) / 64;
        /* Header and footer. */
        if (enc != NULL) {
            /* Name is: 'ENCRYPTED PRIVATE KEY'. */
            *pemSz += 74;
        }
        else {
            /* Name is: 'PRIVATE KEY'. */
            *pemSz += 54;
        }

        /* Allocate enough memory to hold PEM encoded encrypted key. */
        *pem = (byte*)XMALLOC((size_t)*pemSz, NULL, DYNAMIC_TYPE_TMP_BUFFER);
        if (*pem == NULL) {
            res = 0;
        }
        else {
            /* Use end of PEM buffer for key data. */
            key = *pem + *pemSz - keySz;
        }
    }

    if ((res == 1) && (enc != NULL)) {
        /* Set type for PEM. */
        type = PKCS8_ENC_PRIVATEKEY_TYPE;

        if (passwd == NULL) {
            /* Get the password by using callback. */
            passwdSz = cb(password, sizeof(password), 1, ctx);
            if (passwdSz < 0) {
                res = 0;
            }
            passwd = password;
        }

        if (res == 1) {
            /* Encrypt the private key. */
            ret = pem_pkcs8_encrypt(pkey, enc, passwd, passwdSz, key, &keySz);
            if (ret <= 0) {
                res = 0;
            }
        }

        /* Zeroize the password from memory. */
        if ((password == passwd) && (passwdSz > 0)) {
            ForceZero(password, (word32)passwdSz);
        }
    }
    else if ((res == 1) && (enc == NULL)) {
        /* Set type for PEM. */
        type = PKCS8_PRIVATEKEY_TYPE;

        /* Encode private key in PKCS#8 format. */
        ret = pem_pkcs8_encode(pkey, key, &keySz);
        if (ret < 0) {
            res = 0;
        }
    }

    if (res == 1) {
        /* Encode PKCS#8 formatted key to PEM. */
        ret = wc_DerToPemEx(key, keySz, *pem, (word32)*pemSz, NULL, type);
        if (ret < 0) {
            res = 0;
        }
        else {
            *pemSz = ret;
        }
    }

    /* Return appropriate return code. */
    return (res == 0) ? 0 : ret;

}
#endif /* !NO_BIO || (!NO_FILESYSTEM && !NO_STDIO_FILESYSTEM) */

#ifndef NO_BIO
/* Write PEM encoded, PKCS#8 formatted private key to BIO.
 *
 * TODO: OpenSSL returns 1 and 0 only.
 *
 * @param [in] bio       BIO to write to.
 * @param [in] pkey      Private key to write.
 * @param [in] enc       Encryption information to use. May be NULL.
 * @param [in] passwd    Password to use when encrypting. May be NULL.
 * @param [in] passwdSz  Size of password in bytes.
 * @param [in] cb        Password callback. Used when passwd is NULL. May be
 *                       NULL.
 * @param [in] ctx       Context for password callback.
 * @return  Length of PEM encoding on success.
 * @return  0 on failure.
 */
int wolfSSL_PEM_write_bio_PKCS8PrivateKey(WOLFSSL_BIO* bio,
    WOLFSSL_EVP_PKEY* pkey, const WOLFSSL_EVP_CIPHER* enc, char* passwd,
    int passwdSz, wc_pem_password_cb* cb, void* ctx)
{
    byte* pem = NULL;
    int pemSz = 0;
    int res = 1;

    /* Validate parameters. */
    if (bio == NULL) {
        res = 0;
    }
    if (res == 1) {
        /* Write private key to memory. */
        res = pem_write_mem_pkcs8privatekey(&pem, &pemSz, pkey, enc, passwd,
            passwdSz, cb, ctx);
    }

    /* Write encoded key to BIO. */
    if ((res >= 1) && (wolfSSL_BIO_write(bio, pem, pemSz) != pemSz)) {
        res = 0;
    }

    /* Dispose of dynamically allocated memory (pem and key). */
    XFREE(pem, NULL, DYNAMIC_TYPE_TMP_BUFFER);
    return res;
}
#endif /* !NO_BIO */

#if !defined(NO_FILESYSTEM) && !defined(NO_STDIO_FILESYSTEM)
/* Write PEM encoded, PKCS#8 formatted private key to BIO.
 *
 * TODO: OpenSSL returns 1 and 0 only.
 *
 * @param [in] f         File pointer.
 * @param [in] pkey      Private key to write.
 * @param [in] enc       Encryption information to use. May be NULL.
 * @param [in] passwd    Password to use when encrypting. May be NULL.
 * @param [in] passwdSz  Size of password in bytes.
 * @param [in] cb        Password callback. Used when passwd is NULL. May be
 *                       NULL.
 * @param [in] ctx       Context for password callback.
 * @return  Length of PEM encoding on success.
 * @return  0 on failure.
 */
int wolfSSL_PEM_write_PKCS8PrivateKey(XFILE f, WOLFSSL_EVP_PKEY* pkey,
    const WOLFSSL_EVP_CIPHER* enc, char* passwd, int passwdSz,
    wc_pem_password_cb* cb, void* ctx)
{
    byte* pem = NULL;
    int pemSz = 0;
    int res = 1;

    /* Validate parameters. */
    if (f == XBADFILE) {
        res = 0;
    }
    if (res == 1) {
        /* Write private key to memory. */
        res = pem_write_mem_pkcs8privatekey(&pem, &pemSz, pkey, enc, passwd,
            passwdSz, cb, ctx);
    }

    /* Write encoded key to file. */
    if ((res >= 1) && (XFWRITE(pem, 1, (size_t)pemSz, f) != (size_t)pemSz)) {
        res = 0;
    }

    /* Dispose of dynamically allocated memory (pem and key). */
    XFREE(pem, NULL, DYNAMIC_TYPE_TMP_BUFFER);
    return res;
}
#endif /* !NO_FILESYSTEM && !NO_STDIO_FILESYSTEM */

#endif /* !NO_PWDBASED && HAVE_PKCS8 */
#endif /* OPENSSL_ALL */

/*******************************************************************************
 * END OF GENERIC PUBLIC KEY PEM APIs
 ******************************************************************************/

#endif /* !WOLFSSL_PK_INCLUDED */

