/**
 * \file 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

#if !defined(MBEDTLS_CONFIG_FILE)
#include "config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif

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

#define MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED                -0x0037  /**< SHA-256 hardware accelerator failed */

#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
    !defined(inline) && !defined(__cplusplus)
#define inline __inline
#endif

#if !defined(MBEDTLS_SHA256_ALT)
// Regular implementation
//

#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
 *
 * \return         0 if successful
 */
int mbedtls_sha256_starts_ret( 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
 *
 * \return         0 if successful
 */
int mbedtls_sha256_update_ret( 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
 *
 * \return         0 if successful
 */
int mbedtls_sha256_finish_ret( mbedtls_sha256_context *ctx,
                               unsigned char output[32] );

/**
 * \brief          SHA-256 process data block (internal use only)
 *
 * \param ctx      SHA-256 context
 * \param data     buffer holding one block of data
 *
 * \return         0 if successful
 */
int mbedtls_internal_sha256_process( mbedtls_sha256_context *ctx,
                                     const unsigned char data[64] );

#if !defined(MBEDTLS_DEPRECATED_REMOVED)
#if defined(MBEDTLS_DEPRECATED_WARNING)
#define MBEDTLS_DEPRECATED      __attribute__((deprecated))
#else
#define MBEDTLS_DEPRECATED
#endif
/**
 * \brief          SHA-256 context setup
 *
 * \deprecated     Superseded by mbedtls_sha256_starts_ret() in 2.7.0
 *
 * \param ctx      context to be initialized
 * \param is224    0 = use SHA256, 1 = use SHA224
 */
MBEDTLS_DEPRECATED static inline void mbedtls_sha256_starts(
                                                mbedtls_sha256_context *ctx,
                                                int is224 )
{
    mbedtls_sha256_starts_ret( ctx, is224 );
}

/**
 * \brief          SHA-256 process buffer
 *
 * \deprecated     Superseded by mbedtls_sha256_update_ret() in 2.7.0
 *
 * \param ctx      SHA-256 context
 * \param input    buffer holding the data
 * \param ilen     length of the input data
 */
MBEDTLS_DEPRECATED static inline void mbedtls_sha256_update(
                                                mbedtls_sha256_context *ctx,
                                                const unsigned char *input,
                                                size_t ilen )
{
    mbedtls_sha256_update_ret( ctx, input, ilen );
}

/**
 * \brief          SHA-256 final digest
 *
 * \deprecated     Superseded by mbedtls_sha256_finish_ret() in 2.7.0
 *
 * \param ctx      SHA-256 context
 * \param output   SHA-224/256 checksum result
 */
MBEDTLS_DEPRECATED static inline void mbedtls_sha256_finish(
                                                mbedtls_sha256_context *ctx,
                                                unsigned char output[32] )
{
    mbedtls_sha256_finish_ret( ctx, output );
}

/**
 * \brief          SHA-256 process data block (internal use only)
 *
 * \deprecated     Superseded by mbedtls_internal_sha256_process() in 2.7.0
 *
 * \param ctx      SHA-256 context
 * \param data     buffer holding one block of data
 */
MBEDTLS_DEPRECATED static inline void mbedtls_sha256_process(
                                                mbedtls_sha256_context *ctx,
                                                const unsigned char data[64] )
{
    mbedtls_internal_sha256_process( ctx, data );
}

#undef MBEDTLS_DEPRECATED
#endif /* !MBEDTLS_DEPRECATED_REMOVED */

#ifdef __cplusplus
}
#endif

#else  /* MBEDTLS_SHA256_ALT */
#include "sha256_alt.h"
#endif /* MBEDTLS_SHA256_ALT */

#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
 *
 * \return         0 if successful
 */
int mbedtls_sha256_ret( const unsigned char *input,
                        size_t ilen,
                        unsigned char output[32],
                        int is224 );

#if !defined(MBEDTLS_DEPRECATED_REMOVED)
#if defined(MBEDTLS_DEPRECATED_WARNING)
#define MBEDTLS_DEPRECATED      __attribute__((deprecated))
#else
#define MBEDTLS_DEPRECATED
#endif
/**
 * \brief          Output = SHA-256( input buffer )
 *
 * \deprecated     Superseded by mbedtls_sha256_ret() in 2.7.0
 *
 * \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
 */
MBEDTLS_DEPRECATED static inline void mbedtls_sha256(
                                                    const unsigned char *input,
                                                    size_t ilen,
                                                    unsigned char output[32],
                                                    int is224 )
{
    mbedtls_sha256_ret( input, ilen, output, is224 );
}

#undef MBEDTLS_DEPRECATED
#endif /* !MBEDTLS_DEPRECATED_REMOVED */

/**
 * \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 */