/**
 * \file mbedtls_sha256.h
 *
 * \brief SHA-224 and SHA-256 cryptographic hash function
 *
 *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
 *  SPDX-License-Identifier: Apache-2.0
 *
 *  Licensed under the Apache License, Version 2.0 (the "License"); you may
 *  not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *  This file is part of mbed TLS (https://tls.mbed.org)
 */
#ifndef MBEDTLS_SHA256_H
#define MBEDTLS_SHA256_H

//#include <string.h>
#include <stddef.h>
#include <stdint.h>

//#ifndef size_t
//  typedef unsigned int size_t;
//#endif
//#ifndef uint32_t
//typedef unsigned int uint32_t;
//#endif
//#ifndef NULL
//#define NULL  0
//#endif


#ifdef __cplusplus
extern "C" {
#endif

/**
 * \brief          SHA-256 context structure
 */
typedef struct
{
    uint32_t total[2];          /*!< number of bytes processed  */
    uint32_t state[8];          /*!< intermediate digest state  */
    unsigned char buffer[64];   /*!< data block being processed */
    int is224;                  /*!< 0 => SHA-256, else SHA-224 */
}
mbedtls_sha256_context;

/**
 * \brief          Initialize SHA-256 context
 *
 * \param ctx      SHA-256 context to be initialized
 */
void mbedtls_sha256_init( mbedtls_sha256_context *ctx );

/**
 * \brief          Clear SHA-256 context
 *
 * \param ctx      SHA-256 context to be cleared
 */
void mbedtls_sha256_free( mbedtls_sha256_context *ctx );

/**
 * \brief          Clone (the state of) a SHA-256 context
 *
 * \param dst      The destination context
 * \param src      The context to be cloned
 */
void mbedtls_sha256_clone( mbedtls_sha256_context *dst,
                           const mbedtls_sha256_context *src );

/**
 * \brief          SHA-256 context setup
 *
 * \param ctx      context to be initialized
 * \param is224    0 = use SHA256, 1 = use SHA224
 */
void mbedtls_sha256_starts( mbedtls_sha256_context *ctx, int is224 );

/**
 * \brief          SHA-256 process buffer
 *
 * \param ctx      SHA-256 context
 * \param input    buffer holding the  data
 * \param ilen     length of the input data
 */
void mbedtls_sha256_update( mbedtls_sha256_context *ctx, const unsigned char *input,
                    size_t ilen );

/**
 * \brief          SHA-256 final digest
 *
 * \param ctx      SHA-256 context
 * \param output   SHA-224/256 checksum result
 */
void mbedtls_sha256_finish( mbedtls_sha256_context *ctx, unsigned char output[32] );

/* Internal use */
void mbedtls_sha256_process( mbedtls_sha256_context *ctx, const unsigned char data[64] );

unsigned int mbedtls_sha256_hkdf(const unsigned char *key, unsigned int key_len, const unsigned char *salt, unsigned int salt_len,
                        const unsigned char *info, unsigned int info_len, unsigned char *out, unsigned int out_len);

#ifdef __cplusplus
}
#endif


#ifdef __cplusplus
extern "C" {
#endif

/**
 * \brief          Output = SHA-256( input buffer )
 *
 * \param input    buffer holding the  data
 * \param ilen     length of the input data
 * \param output   SHA-224/256 checksum result
 * \param is224    0 = use SHA256, 1 = use SHA224
 */
void mbedtls_sha256( const unsigned char *input, size_t ilen,
           unsigned char output[32], int is224 );

/**
 * \brief          Output = Generic_HMAC( hmac key, input buffer )
 *
 * \param md_info  message digest info
 * \param key      HMAC secret key
 * \param keylen   length of the HMAC key in bytes
 * \param input    buffer holding the  data
 * \param ilen     length of the input data
 * \param output   Generic HMAC-result
 *
 * \returns        0 on success, MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter
 *                 verification fails.
 */
int mbedtls_md_hmac( const unsigned char *key, size_t keylen, const unsigned char *input, size_t ilen,
                unsigned char *output );
/**
 * \brief          Checkup routine
 *
 * \return         0 if successful, or 1 if the test failed
 */
//int mbedtls_sha256_self_test( int verbose );

#ifdef __cplusplus
}
#endif

#endif /* mbedtls_sha256.h */
