/* v3_lib.c */
/*
 * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
 * 1999.
 */
/* ====================================================================
 * Copyright (c) 1999 The OpenSSL Project.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    licensing@OpenSSL.org.
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * (eay@cryptsoft.com).  This product includes software written by Tim
 * Hudson (tjh@cryptsoft.com).
 *
 */
/* X509 v3 extension utilities */

#include <stdio.h>

#include <openssl_grpc/conf.h>
#include <openssl_grpc/err.h>
#include <openssl_grpc/mem.h>
#include <openssl_grpc/obj.h>
#include <openssl_grpc/x509v3.h>

#include "ext_dat.h"
static STACK_OF(X509V3_EXT_METHOD) *ext_list = NULL;

static void ext_list_free(X509V3_EXT_METHOD *ext);

static int ext_stack_cmp(const X509V3_EXT_METHOD **a,
                         const X509V3_EXT_METHOD **b)
{
    return ((*a)->ext_nid - (*b)->ext_nid);
}

int X509V3_EXT_add(X509V3_EXT_METHOD *ext)
{
    if (!ext_list && !(ext_list = sk_X509V3_EXT_METHOD_new(ext_stack_cmp))) {
        OPENSSL_PUT_ERROR(X509V3, ERR_R_MALLOC_FAILURE);
        ext_list_free(ext);
        return 0;
    }
    if (!sk_X509V3_EXT_METHOD_push(ext_list, ext)) {
        OPENSSL_PUT_ERROR(X509V3, ERR_R_MALLOC_FAILURE);
        ext_list_free(ext);
        return 0;
    }
    return 1;
}

static int ext_cmp(const void *void_a, const void *void_b)
{
    const X509V3_EXT_METHOD **a = (const X509V3_EXT_METHOD **)void_a;
    const X509V3_EXT_METHOD **b = (const X509V3_EXT_METHOD **)void_b;
    return ext_stack_cmp(a, b);
}

const X509V3_EXT_METHOD *X509V3_EXT_get_nid(int nid)
{
    X509V3_EXT_METHOD tmp;
    const X509V3_EXT_METHOD *t = &tmp, *const *ret;
    size_t idx;

    if (nid < 0)
        return NULL;
    tmp.ext_nid = nid;
    ret =
        bsearch(&t, standard_exts, STANDARD_EXTENSION_COUNT,
                sizeof(X509V3_EXT_METHOD *), ext_cmp);
    if (ret)
        return *ret;
    if (!ext_list)
        return NULL;

    if (!sk_X509V3_EXT_METHOD_find(ext_list, &idx, &tmp))
        return NULL;
    return sk_X509V3_EXT_METHOD_value(ext_list, idx);
}

const X509V3_EXT_METHOD *X509V3_EXT_get(X509_EXTENSION *ext)
{
    int nid;
    if ((nid = OBJ_obj2nid(ext->object)) == NID_undef)
        return NULL;
    return X509V3_EXT_get_nid(nid);
}

int X509V3_EXT_free(int nid, void *ext_data)
{
    const X509V3_EXT_METHOD *ext_method = X509V3_EXT_get_nid(nid);
    if (ext_method == NULL) {
        OPENSSL_PUT_ERROR(X509V3, X509V3_R_CANNOT_FIND_FREE_FUNCTION);
        return 0;
    }

    if (ext_method->it != NULL)
        ASN1_item_free(ext_data, ASN1_ITEM_ptr(ext_method->it));
    else if (ext_method->ext_free != NULL)
        ext_method->ext_free(ext_data);
    else {
        OPENSSL_PUT_ERROR(X509V3, X509V3_R_CANNOT_FIND_FREE_FUNCTION);
        return 0;
    }

    return 1;
}

int X509V3_EXT_add_list(X509V3_EXT_METHOD *extlist)
{
    for (; extlist->ext_nid != -1; extlist++)
        if (!X509V3_EXT_add(extlist))
            return 0;
    return 1;
}

int X509V3_EXT_add_alias(int nid_to, int nid_from)
{
    const X509V3_EXT_METHOD *ext;
    X509V3_EXT_METHOD *tmpext;

    if (!(ext = X509V3_EXT_get_nid(nid_from))) {
        OPENSSL_PUT_ERROR(X509V3, X509V3_R_EXTENSION_NOT_FOUND);
        return 0;
    }
    if (!
        (tmpext =
         (X509V3_EXT_METHOD *)OPENSSL_malloc(sizeof(X509V3_EXT_METHOD)))) {
        OPENSSL_PUT_ERROR(X509V3, ERR_R_MALLOC_FAILURE);
        return 0;
    }
    *tmpext = *ext;
    tmpext->ext_nid = nid_to;
    tmpext->ext_flags |= X509V3_EXT_DYNAMIC;
    return X509V3_EXT_add(tmpext);
}

void X509V3_EXT_cleanup(void)
{
    sk_X509V3_EXT_METHOD_pop_free(ext_list, ext_list_free);
    ext_list = NULL;
}

static void ext_list_free(X509V3_EXT_METHOD *ext)
{
    if (ext->ext_flags & X509V3_EXT_DYNAMIC)
        OPENSSL_free(ext);
}

/*
 * Legacy function: we don't need to add standard extensions any more because
 * they are now kept in ext_dat.h.
 */

int X509V3_add_standard_extensions(void)
{
    return 1;
}

/* Return an extension internal structure */

void *X509V3_EXT_d2i(X509_EXTENSION *ext)
{
    const X509V3_EXT_METHOD *method;
    const unsigned char *p;

    if (!(method = X509V3_EXT_get(ext)))
        return NULL;
    p = ext->value->data;
    if (method->it)
        return ASN1_item_d2i(NULL, &p, ext->value->length,
                             ASN1_ITEM_ptr(method->it));
    return method->d2i(NULL, &p, ext->value->length);
}

/*
 * Get critical flag and decoded version of extension from a NID. The "idx"
 * variable returns the last found extension and can be used to retrieve
 * multiple extensions of the same NID. However multiple extensions with the
 * same NID is usually due to a badly encoded certificate so if idx is NULL
 * we choke if multiple extensions exist. The "crit" variable is set to the
 * critical value. The return value is the decoded extension or NULL on
 * error. The actual error can have several different causes, the value of
 * *crit reflects the cause: >= 0, extension found but not decoded (reflects
 * critical value). -1 extension not found. -2 extension occurs more than
 * once.
 */

void *X509V3_get_d2i(STACK_OF(X509_EXTENSION) *x, int nid, int *crit,
                     int *idx)
{
    int lastpos;
    size_t i;
    X509_EXTENSION *ex, *found_ex = NULL;
    if (!x) {
        if (idx)
            *idx = -1;
        if (crit)
            *crit = -1;
        return NULL;
    }
    if (idx)
        lastpos = *idx + 1;
    else
        lastpos = 0;
    if (lastpos < 0)
        lastpos = 0;
    for (i = lastpos; i < sk_X509_EXTENSION_num(x); i++) {
        ex = sk_X509_EXTENSION_value(x, i);
        if (OBJ_obj2nid(ex->object) == nid) {
            if (idx) {
                *idx = i;
                found_ex = ex;
                break;
            } else if (found_ex) {
                /* Found more than one */
                if (crit)
                    *crit = -2;
                return NULL;
            }
            found_ex = ex;
        }
    }
    if (found_ex) {
        /* Found it */
        if (crit)
            *crit = X509_EXTENSION_get_critical(found_ex);
        return X509V3_EXT_d2i(found_ex);
    }

    /* Extension not found */
    if (idx)
        *idx = -1;
    if (crit)
        *crit = -1;
    return NULL;
}

/*
 * This function is a general extension append, replace and delete utility.
 * The precise operation is governed by the 'flags' value. The 'crit' and
 * 'value' arguments (if relevant) are the extensions internal structure.
 */

int X509V3_add1_i2d(STACK_OF(X509_EXTENSION) **x, int nid, void *value,
                    int crit, unsigned long flags)
{
    int errcode, extidx = -1;
    X509_EXTENSION *ext = NULL, *extmp;
    STACK_OF(X509_EXTENSION) *ret = NULL;
    unsigned long ext_op = flags & X509V3_ADD_OP_MASK;

    /*
     * If appending we don't care if it exists, otherwise look for existing
     * extension.
     */
    if (ext_op != X509V3_ADD_APPEND)
        extidx = X509v3_get_ext_by_NID(*x, nid, -1);

    /* See if extension exists */
    if (extidx >= 0) {
        /* If keep existing, nothing to do */
        if (ext_op == X509V3_ADD_KEEP_EXISTING)
            return 1;
        /* If default then its an error */
        if (ext_op == X509V3_ADD_DEFAULT) {
            errcode = X509V3_R_EXTENSION_EXISTS;
            goto err;
        }
        /* If delete, just delete it */
        if (ext_op == X509V3_ADD_DELETE) {
            if (!sk_X509_EXTENSION_delete(*x, extidx))
                return -1;
            return 1;
        }
    } else {
        /*
         * If replace existing or delete, error since extension must exist
         */
        if ((ext_op == X509V3_ADD_REPLACE_EXISTING) ||
            (ext_op == X509V3_ADD_DELETE)) {
            errcode = X509V3_R_EXTENSION_NOT_FOUND;
            goto err;
        }
    }

    /*
     * If we get this far then we have to create an extension: could have
     * some flags for alternative encoding schemes...
     */

    ext = X509V3_EXT_i2d(nid, crit, value);

    if (!ext) {
        OPENSSL_PUT_ERROR(X509V3, X509V3_R_ERROR_CREATING_EXTENSION);
        return 0;
    }

    /* If extension exists replace it.. */
    if (extidx >= 0) {
        extmp = sk_X509_EXTENSION_value(*x, extidx);
        X509_EXTENSION_free(extmp);
        if (!sk_X509_EXTENSION_set(*x, extidx, ext))
            return -1;
        return 1;
    }

    if ((ret = *x) == NULL
         && (ret = sk_X509_EXTENSION_new_null()) == NULL)
        goto m_fail;
    if (!sk_X509_EXTENSION_push(ret, ext))
        goto m_fail;

    *x = ret;
    return 1;

 m_fail:
    if (ret != *x)
        sk_X509_EXTENSION_free(ret);
    X509_EXTENSION_free(ext);
    return -1;

 err:
    if (!(flags & X509V3_ADD_SILENT))
        OPENSSL_PUT_ERROR(X509V3, errcode);
    return 0;
}
