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SHA-1 source code

SHA-1

The source code for the SHA-1 algorithm, also called SHA1. This source code is part of the mbed TLS library and represents the most current version in the trunk of the library.
Download mbed TLS

The full algorithm of SHA-1 is further explained in SHA-1 algorithm (Wikipedia).

The code only has a single dependency on config.h in the sha1.c source code file. You can remove this inclusion or just create a simple header file to define one or more of the configuration options that the SHA-256 source code has.

Full documentation on the SHA-1 source code can be found in the API documentation for the SHA-1 module.

You can also download it as part of the latest release of mbed TLS.

Header - sha1.h

The sha1.h header can also be found in the trunk on: sha1.h.

/**
 * \file sha1.h
 *
 * \brief This file contains SHA-1 definitions and functions.
 *
 * The Secure Hash Algorithm 1 (SHA-1) cryptographic hash function is defined in
 * <em>FIPS 180-4: Secure Hash Standard (SHS)</em>.
 *
 * \warning   SHA-1 is considered a weak message digest and its use constitutes
 *            a security risk. We recommend considering stronger message
 *            digests instead.
 */
/*
 *  Copyright (C) 2006-2018, Arm Limited (or its affiliates), 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_SHA1_H
#define MBEDTLS_SHA1_H

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

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

#define MBEDTLS_ERR_SHA1_HW_ACCEL_FAILED                  -0x0035  /**< SHA-1 hardware accelerator failed */

#ifdef __cplusplus
extern "C" {
#endif

#if !defined(MBEDTLS_SHA1_ALT)
// Regular implementation
//

/**
 * \brief          The SHA-1 context structure.
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 */
typedef struct mbedtls_sha1_context
{
    uint32_t total[2];          /*!< The number of Bytes processed.  */
    uint32_t state[5];          /*!< The intermediate digest state.  */
    unsigned char buffer[64];   /*!< The data block being processed. */
}
mbedtls_sha1_context;

#else  /* MBEDTLS_SHA1_ALT */
#include "sha1_alt.h"
#endif /* MBEDTLS_SHA1_ALT */

/**
 * \brief          This function initializes a SHA-1 context.
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \param ctx      The SHA-1 context to initialize.
 *
 */
void mbedtls_sha1_init( mbedtls_sha1_context *ctx );

/**
 * \brief          This function clears a SHA-1 context.
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \param ctx      The SHA-1 context to clear.
 *
 */
void mbedtls_sha1_free( mbedtls_sha1_context *ctx );

/**
 * \brief          This function clones the state of a SHA-1 context.
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \param dst      The SHA-1 context to clone to.
 * \param src      The SHA-1 context to clone from.
 *
 */
void mbedtls_sha1_clone( mbedtls_sha1_context *dst,
                         const mbedtls_sha1_context *src );

/**
 * \brief          This function starts a SHA-1 checksum calculation.
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \param ctx      The SHA-1 context to initialize.
 *
 * \return         \c 0 on success.
 *
 */
int mbedtls_sha1_starts_ret( mbedtls_sha1_context *ctx );

/**
 * \brief          This function feeds an input buffer into an ongoing SHA-1
 *                 checksum calculation.
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \param ctx      The SHA-1 context.
 * \param input    The buffer holding the input data.
 * \param ilen     The length of the input data.
 *
 * \return         \c 0 on success.
 */
int mbedtls_sha1_update_ret( mbedtls_sha1_context *ctx,
                             const unsigned char *input,
                             size_t ilen );

/**
 * \brief          This function finishes the SHA-1 operation, and writes
 *                 the result to the output buffer.
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \param ctx      The SHA-1 context.
 * \param output   The SHA-1 checksum result.
 *
 * \return         \c 0 on success.
 */
int mbedtls_sha1_finish_ret( mbedtls_sha1_context *ctx,
                             unsigned char output[20] );

/**
 * \brief          SHA-1 process data block (internal use only).
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \param ctx      The SHA-1 context.
 * \param data     The data block being processed.
 *
 * \return         \c 0 on success.
 *
 */
int mbedtls_internal_sha1_process( mbedtls_sha1_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          This function starts a SHA-1 checksum calculation.
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \deprecated     Superseded by mbedtls_sha1_starts_ret() in 2.7.0.
 *
 * \param ctx      The SHA-1 context to initialize.
 *
 */
MBEDTLS_DEPRECATED void mbedtls_sha1_starts( mbedtls_sha1_context *ctx );

/**
 * \brief          This function feeds an input buffer into an ongoing SHA-1
 *                 checksum calculation.
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \deprecated     Superseded by mbedtls_sha1_update_ret() in 2.7.0.
 *
 * \param ctx      The SHA-1 context.
 * \param input    The buffer holding the input data.
 * \param ilen     The length of the input data.
 *
 */
MBEDTLS_DEPRECATED void mbedtls_sha1_update( mbedtls_sha1_context *ctx,
                                             const unsigned char *input,
                                             size_t ilen );

/**
 * \brief          This function finishes the SHA-1 operation, and writes
 *                 the result to the output buffer.
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \deprecated     Superseded by mbedtls_sha1_finish_ret() in 2.7.0.
 *
 * \param ctx      The SHA-1 context.
 * \param output   The SHA-1 checksum result.
 *
 */
MBEDTLS_DEPRECATED void mbedtls_sha1_finish( mbedtls_sha1_context *ctx,
                                             unsigned char output[20] );

/**
 * \brief          SHA-1 process data block (internal use only).
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \deprecated     Superseded by mbedtls_internal_sha1_process() in 2.7.0.
 *
 * \param ctx      The SHA-1 context.
 * \param data     The data block being processed.
 *
 */
MBEDTLS_DEPRECATED void mbedtls_sha1_process( mbedtls_sha1_context *ctx,
                                              const unsigned char data[64] );

#undef MBEDTLS_DEPRECATED
#endif /* !MBEDTLS_DEPRECATED_REMOVED */

/**
 * \brief          This function calculates the SHA-1 checksum of a buffer.
 *
 *                 The function allocates the context, performs the
 *                 calculation, and frees the context.
 *
 *                 The SHA-1 result is calculated as
 *                 output = SHA-1(input buffer).
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \param input    The buffer holding the input data.
 * \param ilen     The length of the input data.
 * \param output   The SHA-1 checksum result.
 *
 * \return         \c 0 on success.
 *
 */
int mbedtls_sha1_ret( const unsigned char *input,
                      size_t ilen,
                      unsigned char output[20] );

#if !defined(MBEDTLS_DEPRECATED_REMOVED)
#if defined(MBEDTLS_DEPRECATED_WARNING)
#define MBEDTLS_DEPRECATED      __attribute__((deprecated))
#else
#define MBEDTLS_DEPRECATED
#endif
/**
 * \brief          This function calculates the SHA-1 checksum of a buffer.
 *
 *                 The function allocates the context, performs the
 *                 calculation, and frees the context.
 *
 *                 The SHA-1 result is calculated as
 *                 output = SHA-1(input buffer).
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \deprecated     Superseded by mbedtls_sha1_ret() in 2.7.0
 *
 * \param input    The buffer holding the input data.
 * \param ilen     The length of the input data.
 * \param output   The SHA-1 checksum result.
 *
 */
MBEDTLS_DEPRECATED void mbedtls_sha1( const unsigned char *input,
                                      size_t ilen,
                                      unsigned char output[20] );

#undef MBEDTLS_DEPRECATED
#endif /* !MBEDTLS_DEPRECATED_REMOVED */

/**
 * \brief          The SHA-1 checkup routine.
 *
 * \warning        SHA-1 is considered a weak message digest and its use
 *                 constitutes a security risk. We recommend considering
 *                 stronger message digests instead.
 *
 * \return         \c 0 on success.
 * \return         \c 1 on failure.
 *
 */
int mbedtls_sha1_self_test( int verbose );

#ifdef __cplusplus
}
#endif

#endif /* mbedtls_sha1.h */

Source - sha1.c

The sha1.c source code can also be found in the trunk on: sha1.c.

/*
 *  FIPS-180-1 compliant SHA-1 implementation
 *
 *  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)
 */
/*
 *  The SHA-1 standard was published by NIST in 1993.
 *
 *  http://www.itl.nist.gov/fipspubs/fip180-1.htm
 */

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

#if defined(MBEDTLS_SHA1_C)

#include "mbedtls/sha1.h"
#include "mbedtls/platform_util.h"

#include <string.h>

#if defined(MBEDTLS_SELF_TEST)
#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#include <stdio.h>
#define mbedtls_printf printf
#endif /* MBEDTLS_PLATFORM_C */
#endif /* MBEDTLS_SELF_TEST */

#if !defined(MBEDTLS_SHA1_ALT)

/*
 * 32-bit integer manipulation macros (big endian)
 */
#ifndef GET_UINT32_BE
#define GET_UINT32_BE(n,b,i)                            \
{                                                       \
    (n) = ( (uint32_t) (b)[(i)    ] << 24 )             \
        | ( (uint32_t) (b)[(i) + 1] << 16 )             \
        | ( (uint32_t) (b)[(i) + 2] <<  8 )             \
        | ( (uint32_t) (b)[(i) + 3]       );            \
}
#endif

#ifndef PUT_UINT32_BE
#define PUT_UINT32_BE(n,b,i)                            \
{                                                       \
    (b)[(i)    ] = (unsigned char) ( (n) >> 24 );       \
    (b)[(i) + 1] = (unsigned char) ( (n) >> 16 );       \
    (b)[(i) + 2] = (unsigned char) ( (n) >>  8 );       \
    (b)[(i) + 3] = (unsigned char) ( (n)       );       \
}
#endif

void mbedtls_sha1_init( mbedtls_sha1_context *ctx )
{
    memset( ctx, 0, sizeof( mbedtls_sha1_context ) );
}

void mbedtls_sha1_free( mbedtls_sha1_context *ctx )
{
    if( ctx == NULL )
        return;

    mbedtls_platform_zeroize( ctx, sizeof( mbedtls_sha1_context ) );
}

void mbedtls_sha1_clone( mbedtls_sha1_context *dst,
                         const mbedtls_sha1_context *src )
{
    *dst = *src;
}

/*
 * SHA-1 context setup
 */
int mbedtls_sha1_starts_ret( mbedtls_sha1_context *ctx )
{
    ctx->total[0] = 0;
    ctx->total[1] = 0;

    ctx->state[0] = 0x67452301;
    ctx->state[1] = 0xEFCDAB89;
    ctx->state[2] = 0x98BADCFE;
    ctx->state[3] = 0x10325476;
    ctx->state[4] = 0xC3D2E1F0;

    return( 0 );
}

#if !defined(MBEDTLS_DEPRECATED_REMOVED)
void mbedtls_sha1_starts( mbedtls_sha1_context *ctx )
{
    mbedtls_sha1_starts_ret( ctx );
}
#endif

#if !defined(MBEDTLS_SHA1_PROCESS_ALT)
int mbedtls_internal_sha1_process( mbedtls_sha1_context *ctx,
                                   const unsigned char data[64] )
{
    uint32_t temp, W[16], A, B, C, D, E;

    GET_UINT32_BE( W[ 0], data,  0 );
    GET_UINT32_BE( W[ 1], data,  4 );
    GET_UINT32_BE( W[ 2], data,  8 );
    GET_UINT32_BE( W[ 3], data, 12 );
    GET_UINT32_BE( W[ 4], data, 16 );
    GET_UINT32_BE( W[ 5], data, 20 );
    GET_UINT32_BE( W[ 6], data, 24 );
    GET_UINT32_BE( W[ 7], data, 28 );
    GET_UINT32_BE( W[ 8], data, 32 );
    GET_UINT32_BE( W[ 9], data, 36 );
    GET_UINT32_BE( W[10], data, 40 );
    GET_UINT32_BE( W[11], data, 44 );
    GET_UINT32_BE( W[12], data, 48 );
    GET_UINT32_BE( W[13], data, 52 );
    GET_UINT32_BE( W[14], data, 56 );
    GET_UINT32_BE( W[15], data, 60 );

#define S(x,n) ((x << n) | ((x & 0xFFFFFFFF) >> (32 - n)))

#define R(t)                                            \
(                                                       \
    temp = W[( t -  3 ) & 0x0F] ^ W[( t - 8 ) & 0x0F] ^ \
           W[( t - 14 ) & 0x0F] ^ W[  t       & 0x0F],  \
    ( W[t & 0x0F] = S(temp,1) )                         \
)

#define P(a,b,c,d,e,x)                                  \
{                                                       \
    e += S(a,5) + F(b,c,d) + K + x; b = S(b,30);        \
}

    A = ctx->state[0];
    B = ctx->state[1];
    C = ctx->state[2];
    D = ctx->state[3];
    E = ctx->state[4];

#define F(x,y,z) (z ^ (x & (y ^ z)))
#define K 0x5A827999

    P( A, B, C, D, E, W[0]  );
    P( E, A, B, C, D, W[1]  );
    P( D, E, A, B, C, W[2]  );
    P( C, D, E, A, B, W[3]  );
    P( B, C, D, E, A, W[4]  );
    P( A, B, C, D, E, W[5]  );
    P( E, A, B, C, D, W[6]  );
    P( D, E, A, B, C, W[7]  );
    P( C, D, E, A, B, W[8]  );
    P( B, C, D, E, A, W[9]  );
    P( A, B, C, D, E, W[10] );
    P( E, A, B, C, D, W[11] );
    P( D, E, A, B, C, W[12] );
    P( C, D, E, A, B, W[13] );
    P( B, C, D, E, A, W[14] );
    P( A, B, C, D, E, W[15] );
    P( E, A, B, C, D, R(16) );
    P( D, E, A, B, C, R(17) );
    P( C, D, E, A, B, R(18) );
    P( B, C, D, E, A, R(19) );

#undef K
#undef F

#define F(x,y,z) (x ^ y ^ z)
#define K 0x6ED9EBA1

    P( A, B, C, D, E, R(20) );
    P( E, A, B, C, D, R(21) );
    P( D, E, A, B, C, R(22) );
    P( C, D, E, A, B, R(23) );
    P( B, C, D, E, A, R(24) );
    P( A, B, C, D, E, R(25) );
    P( E, A, B, C, D, R(26) );
    P( D, E, A, B, C, R(27) );
    P( C, D, E, A, B, R(28) );
    P( B, C, D, E, A, R(29) );
    P( A, B, C, D, E, R(30) );
    P( E, A, B, C, D, R(31) );
    P( D, E, A, B, C, R(32) );
    P( C, D, E, A, B, R(33) );
    P( B, C, D, E, A, R(34) );
    P( A, B, C, D, E, R(35) );
    P( E, A, B, C, D, R(36) );
    P( D, E, A, B, C, R(37) );
    P( C, D, E, A, B, R(38) );
    P( B, C, D, E, A, R(39) );

#undef K
#undef F

#define F(x,y,z) ((x & y) | (z & (x | y)))
#define K 0x8F1BBCDC

    P( A, B, C, D, E, R(40) );
    P( E, A, B, C, D, R(41) );
    P( D, E, A, B, C, R(42) );
    P( C, D, E, A, B, R(43) );
    P( B, C, D, E, A, R(44) );
    P( A, B, C, D, E, R(45) );
    P( E, A, B, C, D, R(46) );
    P( D, E, A, B, C, R(47) );
    P( C, D, E, A, B, R(48) );
    P( B, C, D, E, A, R(49) );
    P( A, B, C, D, E, R(50) );
    P( E, A, B, C, D, R(51) );
    P( D, E, A, B, C, R(52) );
    P( C, D, E, A, B, R(53) );
    P( B, C, D, E, A, R(54) );
    P( A, B, C, D, E, R(55) );
    P( E, A, B, C, D, R(56) );
    P( D, E, A, B, C, R(57) );
    P( C, D, E, A, B, R(58) );
    P( B, C, D, E, A, R(59) );

#undef K
#undef F

#define F(x,y,z) (x ^ y ^ z)
#define K 0xCA62C1D6

    P( A, B, C, D, E, R(60) );
    P( E, A, B, C, D, R(61) );
    P( D, E, A, B, C, R(62) );
    P( C, D, E, A, B, R(63) );
    P( B, C, D, E, A, R(64) );
    P( A, B, C, D, E, R(65) );
    P( E, A, B, C, D, R(66) );
    P( D, E, A, B, C, R(67) );
    P( C, D, E, A, B, R(68) );
    P( B, C, D, E, A, R(69) );
    P( A, B, C, D, E, R(70) );
    P( E, A, B, C, D, R(71) );
    P( D, E, A, B, C, R(72) );
    P( C, D, E, A, B, R(73) );
    P( B, C, D, E, A, R(74) );
    P( A, B, C, D, E, R(75) );
    P( E, A, B, C, D, R(76) );
    P( D, E, A, B, C, R(77) );
    P( C, D, E, A, B, R(78) );
    P( B, C, D, E, A, R(79) );

#undef K
#undef F

    ctx->state[0] += A;
    ctx->state[1] += B;
    ctx->state[2] += C;
    ctx->state[3] += D;
    ctx->state[4] += E;

    return( 0 );
}

#if !defined(MBEDTLS_DEPRECATED_REMOVED)
void mbedtls_sha1_process( mbedtls_sha1_context *ctx,
                           const unsigned char data[64] )
{
    mbedtls_internal_sha1_process( ctx, data );
}
#endif
#endif /* !MBEDTLS_SHA1_PROCESS_ALT */

/*
 * SHA-1 process buffer
 */
int mbedtls_sha1_update_ret( mbedtls_sha1_context *ctx,
                             const unsigned char *input,
                             size_t ilen )
{
    int ret;
    size_t fill;
    uint32_t left;

    if( ilen == 0 )
        return( 0 );

    left = ctx->total[0] & 0x3F;
    fill = 64 - left;

    ctx->total[0] += (uint32_t) ilen;
    ctx->total[0] &= 0xFFFFFFFF;

    if( ctx->total[0] < (uint32_t) ilen )
        ctx->total[1]++;

    if( left && ilen >= fill )
    {
        memcpy( (void *) (ctx->buffer + left), input, fill );

        if( ( ret = mbedtls_internal_sha1_process( ctx, ctx->buffer ) ) != 0 )
            return( ret );

        input += fill;
        ilen  -= fill;
        left = 0;
    }

    while( ilen >= 64 )
    {
        if( ( ret = mbedtls_internal_sha1_process( ctx, input ) ) != 0 )
            return( ret );

        input += 64;
        ilen  -= 64;
    }

    if( ilen > 0 )
        memcpy( (void *) (ctx->buffer + left), input, ilen );

    return( 0 );
}

#if !defined(MBEDTLS_DEPRECATED_REMOVED)
void mbedtls_sha1_update( mbedtls_sha1_context *ctx,
                          const unsigned char *input,
                          size_t ilen )
{
    mbedtls_sha1_update_ret( ctx, input, ilen );
}
#endif

/*
 * SHA-1 final digest
 */
int mbedtls_sha1_finish_ret( mbedtls_sha1_context *ctx,
                             unsigned char output[20] )
{
    int ret;
    uint32_t used;
    uint32_t high, low;

    /*
     * Add padding: 0x80 then 0x00 until 8 bytes remain for the length
     */
    used = ctx->total[0] & 0x3F;

    ctx->buffer[used++] = 0x80;

    if( used <= 56 )
    {
        /* Enough room for padding + length in current block */
        memset( ctx->buffer + used, 0, 56 - used );
    }
    else
    {
        /* We'll need an extra block */
        memset( ctx->buffer + used, 0, 64 - used );

        if( ( ret = mbedtls_internal_sha1_process( ctx, ctx->buffer ) ) != 0 )
            return( ret );

        memset( ctx->buffer, 0, 56 );
    }

    /*
     * Add message length
     */
    high = ( ctx->total[0] >> 29 )
         | ( ctx->total[1] <<  3 );
    low  = ( ctx->total[0] <<  3 );

    PUT_UINT32_BE( high, ctx->buffer, 56 );
    PUT_UINT32_BE( low,  ctx->buffer, 60 );

    if( ( ret = mbedtls_internal_sha1_process( ctx, ctx->buffer ) ) != 0 )
        return( ret );

    /*
     * Output final state
     */
    PUT_UINT32_BE( ctx->state[0], output,  0 );
    PUT_UINT32_BE( ctx->state[1], output,  4 );
    PUT_UINT32_BE( ctx->state[2], output,  8 );
    PUT_UINT32_BE( ctx->state[3], output, 12 );
    PUT_UINT32_BE( ctx->state[4], output, 16 );

    return( 0 );
}

#if !defined(MBEDTLS_DEPRECATED_REMOVED)
void mbedtls_sha1_finish( mbedtls_sha1_context *ctx,
                          unsigned char output[20] )
{
    mbedtls_sha1_finish_ret( ctx, output );
}
#endif

#endif /* !MBEDTLS_SHA1_ALT */

/*
 * output = SHA-1( input buffer )
 */
int mbedtls_sha1_ret( const unsigned char *input,
                      size_t ilen,
                      unsigned char output[20] )
{
    int ret;
    mbedtls_sha1_context ctx;

    mbedtls_sha1_init( &ctx );

    if( ( ret = mbedtls_sha1_starts_ret( &ctx ) ) != 0 )
        goto exit;

    if( ( ret = mbedtls_sha1_update_ret( &ctx, input, ilen ) ) != 0 )
        goto exit;

    if( ( ret = mbedtls_sha1_finish_ret( &ctx, output ) ) != 0 )
        goto exit;

exit:
    mbedtls_sha1_free( &ctx );

    return( ret );
}

#if !defined(MBEDTLS_DEPRECATED_REMOVED)
void mbedtls_sha1( const unsigned char *input,
                   size_t ilen,
                   unsigned char output[20] )
{
    mbedtls_sha1_ret( input, ilen, output );
}
#endif

#if defined(MBEDTLS_SELF_TEST)
/*
 * FIPS-180-1 test vectors
 */
static const unsigned char sha1_test_buf[3][57] =
{
    { "abc" },
    { "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq" },
    { "" }
};

static const size_t sha1_test_buflen[3] =
{
    3, 56, 1000
};

static const unsigned char sha1_test_sum[3][20] =
{
    { 0xA9, 0x99, 0x3E, 0x36, 0x47, 0x06, 0x81, 0x6A, 0xBA, 0x3E,
      0x25, 0x71, 0x78, 0x50, 0xC2, 0x6C, 0x9C, 0xD0, 0xD8, 0x9D },
    { 0x84, 0x98, 0x3E, 0x44, 0x1C, 0x3B, 0xD2, 0x6E, 0xBA, 0xAE,
      0x4A, 0xA1, 0xF9, 0x51, 0x29, 0xE5, 0xE5, 0x46, 0x70, 0xF1 },
    { 0x34, 0xAA, 0x97, 0x3C, 0xD4, 0xC4, 0xDA, 0xA4, 0xF6, 0x1E,
      0xEB, 0x2B, 0xDB, 0xAD, 0x27, 0x31, 0x65, 0x34, 0x01, 0x6F }
};

/*
 * Checkup routine
 */
int mbedtls_sha1_self_test( int verbose )
{
    int i, j, buflen, ret = 0;
    unsigned char buf[1024];
    unsigned char sha1sum[20];
    mbedtls_sha1_context ctx;

    mbedtls_sha1_init( &ctx );

    /*
     * SHA-1
     */
    for( i = 0; i < 3; i++ )
    {
        if( verbose != 0 )
            mbedtls_printf( "  SHA-1 test #%d: ", i + 1 );

        if( ( ret = mbedtls_sha1_starts_ret( &ctx ) ) != 0 )
            goto fail;

        if( i == 2 )
        {
            memset( buf, 'a', buflen = 1000 );

            for( j = 0; j < 1000; j++ )
            {
                ret = mbedtls_sha1_update_ret( &ctx, buf, buflen );
                if( ret != 0 )
                    goto fail;
            }
        }
        else
        {
            ret = mbedtls_sha1_update_ret( &ctx, sha1_test_buf[i],
                                           sha1_test_buflen[i] );
            if( ret != 0 )
                goto fail;
        }

        if( ( ret = mbedtls_sha1_finish_ret( &ctx, sha1sum ) ) != 0 )
            goto fail;

        if( memcmp( sha1sum, sha1_test_sum[i], 20 ) != 0 )
        {
            ret = 1;
            goto fail;
        }

        if( verbose != 0 )
            mbedtls_printf( "passed\n" );
    }

    if( verbose != 0 )
        mbedtls_printf( "\n" );

    goto exit;

fail:
    if( verbose != 0 )
        mbedtls_printf( "failed\n" );

exit:
    mbedtls_sha1_free( &ctx );

    return( ret );
}

#endif /* MBEDTLS_SELF_TEST */

#endif /* MBEDTLS_SHA1_C */