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

#include "common.h"

#if defined(MBEDTLS_SHA1_C)

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

#include <string.h>

#include "mbedtls/platform.h"

#if !defined(MBEDTLS_SHA1_ALT)

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( 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_SHA1_PROCESS_ALT)
int mbedtls_internal_sha1_process( mbedtls_sha1_context *ctx,
                                   const unsigned char data[64] )
{
    struct
    {
        uint32_t temp, W[16], A, B, C, D, E;
    } local;

    local.W[ 0] = MBEDTLS_GET_UINT32_BE( data,  0 );
    local.W[ 1] = MBEDTLS_GET_UINT32_BE( data,  4 );
    local.W[ 2] = MBEDTLS_GET_UINT32_BE( data,  8 );
    local.W[ 3] = MBEDTLS_GET_UINT32_BE( data, 12 );
    local.W[ 4] = MBEDTLS_GET_UINT32_BE( data, 16 );
    local.W[ 5] = MBEDTLS_GET_UINT32_BE( data, 20 );
    local.W[ 6] = MBEDTLS_GET_UINT32_BE( data, 24 );
    local.W[ 7] = MBEDTLS_GET_UINT32_BE( data, 28 );
    local.W[ 8] = MBEDTLS_GET_UINT32_BE( data, 32 );
    local.W[ 9] = MBEDTLS_GET_UINT32_BE( data, 36 );
    local.W[10] = MBEDTLS_GET_UINT32_BE( data, 40 );
    local.W[11] = MBEDTLS_GET_UINT32_BE( data, 44 );
    local.W[12] = MBEDTLS_GET_UINT32_BE( data, 48 );
    local.W[13] = MBEDTLS_GET_UINT32_BE( data, 52 );
    local.W[14] = MBEDTLS_GET_UINT32_BE( data, 56 );
    local.W[15] = MBEDTLS_GET_UINT32_BE( data, 60 );

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

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

#define P(a,b,c,d,e,x)                                          \
    do                                                          \
    {                                                           \
        (e) += S((a),5) + F((b),(c),(d)) + K + (x);             \
        (b) = S((b),30);                                        \
    } while( 0 )

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

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

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

#undef K
#undef F

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

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

#undef K
#undef F

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

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

#undef K
#undef F

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

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

#undef K
#undef F

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

    /* Zeroise buffers and variables to clear sensitive data from memory. */
    mbedtls_platform_zeroize( &local, sizeof( local ) );

    return( 0 );
}

#endif /* !MBEDTLS_SHA1_PROCESS_ALT */

/*
 * SHA-1 process buffer
 */
int mbedtls_sha1_update( mbedtls_sha1_context *ctx,
                             const unsigned char *input,
                             size_t ilen )
{
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
    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 );
}

/*
 * SHA-1 final digest
 */
int mbedtls_sha1_finish( mbedtls_sha1_context *ctx,
                             unsigned char output[20] )
{
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
    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 );

    MBEDTLS_PUT_UINT32_BE( high, ctx->buffer, 56 );
    MBEDTLS_PUT_UINT32_BE( low,  ctx->buffer, 60 );

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

    /*
     * Output final state
     */
    MBEDTLS_PUT_UINT32_BE( ctx->state[0], output,  0 );
    MBEDTLS_PUT_UINT32_BE( ctx->state[1], output,  4 );
    MBEDTLS_PUT_UINT32_BE( ctx->state[2], output,  8 );
    MBEDTLS_PUT_UINT32_BE( ctx->state[3], output, 12 );
    MBEDTLS_PUT_UINT32_BE( ctx->state[4], output, 16 );

    return( 0 );
}

#endif /* !MBEDTLS_SHA1_ALT */

/*
 * output = SHA-1( input buffer )
 */
int mbedtls_sha1( const unsigned char *input,
                      size_t ilen,
                      unsigned char output[20] )
{
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
    mbedtls_sha1_context ctx;

    mbedtls_sha1_init( &ctx );

    if( ( ret = mbedtls_sha1_starts( &ctx ) ) != 0 )
        goto exit;

    if( ( ret = mbedtls_sha1_update( &ctx, input, ilen ) ) != 0 )
        goto exit;

    if( ( ret = mbedtls_sha1_finish( &ctx, output ) ) != 0 )
        goto exit;

exit:
    mbedtls_sha1_free( &ctx );

    return( ret );
}

#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( &ctx ) ) != 0 )
            goto fail;

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

            for( j = 0; j < 1000; j++ )
            {
                ret = mbedtls_sha1_update( &ctx, buf, buflen );
                if( ret != 0 )
                    goto fail;
            }
        }
        else
        {
            ret = mbedtls_sha1_update( &ctx, sha1_test_buf[i],
                                           sha1_test_buflen[i] );
            if( ret != 0 )
                goto fail;
        }

        if( ( ret = mbedtls_sha1_finish( &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 */
