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mbedtls/library/md.c

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/**
* \file mbedtls_md.c
*
* \brief Generic message digest wrapper for mbed TLS
*
* \author Adriaan de Jong <dejong@fox-it.com>
*
* 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)
*/
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#if defined(MBEDTLS_MD_C)
#include "mbedtls/md.h"
#include "mbedtls/platform_util.h"
#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#include <stdlib.h>
#define mbedtls_calloc calloc
#define mbedtls_free free
#endif
#include <string.h>
#if defined(MBEDTLS_FS_IO)
#include <stdio.h>
#endif
#if !defined(MBEDTLS_MD_SINGLE_HASH)
/*
*
* Definitions of MD information structures for various digests.
*
*/
/*
* MD-2
*/
#if defined(MBEDTLS_MD2_C)
const mbedtls_md_info_t mbedtls_md2_info = {
MBEDTLS_MD_MD2,
"MD2",
16,
16,
mbedtls_md2_starts_wrap,
mbedtls_md2_update_wrap,
mbedtls_md2_finish_wrap,
mbedtls_md2_ret,
mbedtls_md2_ctx_alloc,
mbedtls_md2_ctx_free,
mbedtls_md2_clone_wrap,
mbedtls_md2_process_wrap,
};
#endif /* MBEDTLS_MD2_C */
/*
* MD-4
*/
#if defined(MBEDTLS_MD4_C)
const mbedtls_md_info_t mbedtls_md4_info = {
MBEDTLS_MD_MD4,
"MD4",
16,
64,
mbedtls_md4_starts_wrap,
mbedtls_md4_update_wrap,
mbedtls_md4_finish_wrap,
mbedtls_md4_ret,
mbedtls_md4_ctx_alloc,
mbedtls_md4_ctx_free,
mbedtls_md4_clone_wrap,
mbedtls_md4_process_wrap,
};
#endif /* MBEDTLS_MD4_C */
/*
* MD-5
*/
#if defined(MBEDTLS_MD5_C)
const mbedtls_md_info_t mbedtls_md5_info = {
MBEDTLS_MD_MD5,
"MD5",
16,
64,
mbedtls_md5_starts_wrap,
mbedtls_md5_update_wrap,
mbedtls_md5_finish_wrap,
mbedtls_md5_ret,
mbedtls_md5_ctx_alloc,
mbedtls_md5_ctx_free,
mbedtls_md5_clone_wrap,
mbedtls_md5_process_wrap,
};
#endif /* MBEDTLS_MD5_C */
/*
* RIPEMD-160
*/
#if defined(MBEDTLS_RIPEMD160_C)
const mbedtls_md_info_t mbedtls_ripemd160_info = {
MBEDTLS_MD_RIPEMD160,
"RIPEMD160",
20,
64,
mbedtls_ripemd160_starts_wrap,
mbedtls_ripemd160_update_wrap,
mbedtls_ripemd160_finish_wrap,
mbedtls_ripemd160_ret,
mbedtls_ripemd160_ctx_alloc,
mbedtls_ripemd160_ctx_free,
mbedtls_ripemd160_clone_wrap,
mbedtls_ripemd160_process_wrap,
};
#endif /* MBEDTLS_RIPEMD160_C */
/*
* SHA-1
*/
#if defined(MBEDTLS_SHA1_C)
const mbedtls_md_info_t mbedtls_sha1_info = {
MBEDTLS_MD_SHA1,
"SHA1",
20,
64,
mbedtls_sha1_starts_wrap,
mbedtls_sha1_update_wrap,
mbedtls_sha1_finish_wrap,
mbedtls_sha1_ret,
mbedtls_sha1_ctx_alloc,
mbedtls_sha1_ctx_free,
mbedtls_sha1_clone_wrap,
mbedtls_sha1_process_wrap,
};
#endif /* MBEDTLS_SHA1_C */
/*
* SHA-224 and SHA-256
*/
#if defined(MBEDTLS_SHA256_C)
#if !defined(MBEDTLS_SHA256_NO_SHA224)
const mbedtls_md_info_t mbedtls_sha224_info = {
MBEDTLS_MD_SHA224,
"SHA224",
28,
64,
mbedtls_sha224_starts_wrap,
mbedtls_sha224_update_wrap,
mbedtls_sha224_finish_wrap,
mbedtls_sha224_wrap,
mbedtls_sha224_ctx_alloc,
mbedtls_sha224_ctx_free,
mbedtls_sha224_clone_wrap,
mbedtls_sha224_process_wrap,
};
#endif /* !MBEDTLS_SHA256_NO_SHA224 */
const mbedtls_md_info_t mbedtls_sha256_info =
MBEDTLS_MD_INFO( MBEDTLS_MD_INFO_SHA256 );
#endif /* MBEDTLS_SHA256_C */
/*
* SHA-384 and SHA-512
*/
#if defined(MBEDTLS_SHA512_C)
const mbedtls_md_info_t mbedtls_sha384_info = {
MBEDTLS_MD_SHA384,
"SHA384",
48,
128,
mbedtls_sha384_starts_wrap,
mbedtls_sha384_update_wrap,
mbedtls_sha384_finish_wrap,
mbedtls_sha384_wrap,
mbedtls_sha384_ctx_alloc,
mbedtls_sha384_ctx_free,
mbedtls_sha384_clone_wrap,
mbedtls_sha384_process_wrap,
};
const mbedtls_md_info_t mbedtls_sha512_info = {
MBEDTLS_MD_SHA512,
"SHA512",
64,
128,
mbedtls_sha512_starts_wrap,
mbedtls_sha384_update_wrap,
mbedtls_sha384_finish_wrap,
mbedtls_sha512_wrap,
mbedtls_sha384_ctx_alloc,
mbedtls_sha384_ctx_free,
mbedtls_sha384_clone_wrap,
mbedtls_sha384_process_wrap,
};
#endif /* MBEDTLS_SHA512_C */
/*
* Reminder: update profiles in x509_crt.c when adding a new hash!
*/
static const int supported_digests[] = {
#if defined(MBEDTLS_SHA512_C)
MBEDTLS_MD_SHA512,
MBEDTLS_MD_SHA384,
#endif
#if defined(MBEDTLS_SHA256_C)
MBEDTLS_MD_SHA256,
#if !defined(MBEDTLS_SHA256_NO_SHA224)
MBEDTLS_MD_SHA224,
#endif
#endif /* MBEDTLS_SHA256_C */
#if defined(MBEDTLS_SHA1_C)
MBEDTLS_MD_SHA1,
#endif
#if defined(MBEDTLS_RIPEMD160_C)
MBEDTLS_MD_RIPEMD160,
#endif
#if defined(MBEDTLS_MD5_C)
MBEDTLS_MD_MD5,
#endif
#if defined(MBEDTLS_MD4_C)
MBEDTLS_MD_MD4,
#endif
#if defined(MBEDTLS_MD2_C)
MBEDTLS_MD_MD2,
#endif
MBEDTLS_MD_NONE
};
const int *mbedtls_md_list( void )
{
return( supported_digests );
}
mbedtls_md_handle_t mbedtls_md_info_from_string( const char *md_name )
{
if( NULL == md_name )
return( NULL );
/* Get the appropriate digest information */
#if defined(MBEDTLS_MD2_C)
if( !strcmp( "MD2", md_name ) )
return mbedtls_md_info_from_type( MBEDTLS_MD_MD2 );
#endif
#if defined(MBEDTLS_MD4_C)
if( !strcmp( "MD4", md_name ) )
return mbedtls_md_info_from_type( MBEDTLS_MD_MD4 );
#endif
#if defined(MBEDTLS_MD5_C)
if( !strcmp( "MD5", md_name ) )
return mbedtls_md_info_from_type( MBEDTLS_MD_MD5 );
#endif
#if defined(MBEDTLS_RIPEMD160_C)
if( !strcmp( "RIPEMD160", md_name ) )
return mbedtls_md_info_from_type( MBEDTLS_MD_RIPEMD160 );
#endif
#if defined(MBEDTLS_SHA1_C)
if( !strcmp( "SHA1", md_name ) || !strcmp( "SHA", md_name ) )
return mbedtls_md_info_from_type( MBEDTLS_MD_SHA1 );
#endif
#if defined(MBEDTLS_SHA256_C)
#if !defined(MBEDTLS_SHA256_NO_SHA224)
if( !strcmp( "SHA224", md_name ) )
return mbedtls_md_info_from_type( MBEDTLS_MD_SHA224 );
#endif
if( !strcmp( "SHA256", md_name ) )
return mbedtls_md_info_from_type( MBEDTLS_MD_SHA256 );
#endif /* MBEDTLS_SHA256_C */
#if defined(MBEDTLS_SHA512_C)
if( !strcmp( "SHA384", md_name ) )
return mbedtls_md_info_from_type( MBEDTLS_MD_SHA384 );
if( !strcmp( "SHA512", md_name ) )
return mbedtls_md_info_from_type( MBEDTLS_MD_SHA512 );
#endif
return( NULL );
}
mbedtls_md_handle_t mbedtls_md_info_from_type( mbedtls_md_type_t md_type )
{
switch( md_type )
{
#if defined(MBEDTLS_MD2_C)
case MBEDTLS_MD_MD2:
return( &mbedtls_md2_info );
#endif
#if defined(MBEDTLS_MD4_C)
case MBEDTLS_MD_MD4:
return( &mbedtls_md4_info );
#endif
#if defined(MBEDTLS_MD5_C)
case MBEDTLS_MD_MD5:
return( &mbedtls_md5_info );
#endif
#if defined(MBEDTLS_RIPEMD160_C)
case MBEDTLS_MD_RIPEMD160:
return( &mbedtls_ripemd160_info );
#endif
#if defined(MBEDTLS_SHA1_C)
case MBEDTLS_MD_SHA1:
return( &mbedtls_sha1_info );
#endif
#if defined(MBEDTLS_SHA256_C)
#if !defined(MBEDTLS_SHA256_NO_SHA224)
case MBEDTLS_MD_SHA224:
return( &mbedtls_sha224_info );
#endif
case MBEDTLS_MD_SHA256:
return( &mbedtls_sha256_info );
#endif /* MBEDTLS_SHA256_C */
#if defined(MBEDTLS_SHA512_C)
case MBEDTLS_MD_SHA384:
return( &mbedtls_sha384_info );
case MBEDTLS_MD_SHA512:
return( &mbedtls_sha512_info );
#endif
default:
return( NULL );
}
}
#else /* MBEDTLS_MD_SINGLE_HASH */
const int *mbedtls_md_list( void )
{
static int single_hash[2] =
{ MBEDTLS_MD_INFO_TYPE( MBEDTLS_MD_SINGLE_HASH ),
MBEDTLS_MD_INVALID_HANDLE };
return( single_hash );
}
mbedtls_md_handle_t mbedtls_md_info_from_string( const char *md_name )
{
static const char * const hash_name =
MBEDTLS_MD_INFO_NAME( MBEDTLS_MD_SINGLE_HASH );
if( md_name != NULL && strcmp( hash_name, md_name ) == 0 )
return( MBEDTLS_MD_UNIQUE_VALID_HANDLE );
return( MBEDTLS_MD_INVALID_HANDLE );
}
mbedtls_md_handle_t mbedtls_md_info_from_type( mbedtls_md_type_t md_type )
{
static const mbedtls_md_type_t hash_type =
MBEDTLS_MD_INFO_TYPE( MBEDTLS_MD_SINGLE_HASH );
if( hash_type == md_type )
return( MBEDTLS_MD_UNIQUE_VALID_HANDLE );
return( MBEDTLS_MD_INVALID_HANDLE );
}
#endif /* MBEDTLS_MD_SINGLE_HASH */
void mbedtls_md_init( mbedtls_md_context_t *ctx )
{
memset( ctx, 0, sizeof( mbedtls_md_context_t ) );
}
void mbedtls_md_free( mbedtls_md_context_t *ctx )
{
if( ctx == NULL || mbedtls_md_get_handle( ctx ) == MBEDTLS_MD_INVALID_HANDLE )
return;
if( ctx->md_ctx != NULL )
{
mbedtls_md_info_ctx_free( mbedtls_md_get_handle( ctx ), ctx->md_ctx );
}
if( ctx->hmac_ctx != NULL )
{
mbedtls_platform_zeroize( ctx->hmac_ctx,
2 * mbedtls_md_info_block_size( mbedtls_md_get_handle( ctx ) ) );
mbedtls_free( ctx->hmac_ctx );
}
mbedtls_platform_zeroize( ctx, sizeof( mbedtls_md_context_t ) );
}
int mbedtls_md_clone( mbedtls_md_context_t *dst,
const mbedtls_md_context_t *src )
{
if( dst == NULL || mbedtls_md_get_handle( dst ) == MBEDTLS_MD_INVALID_HANDLE ||
src == NULL || mbedtls_md_get_handle( src ) == MBEDTLS_MD_INVALID_HANDLE ||
mbedtls_md_get_handle( dst ) != mbedtls_md_get_handle( src ) )
{
return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
}
mbedtls_md_info_clone( mbedtls_md_get_handle( dst ),
dst->md_ctx, src->md_ctx );
return( 0 );
}
#if ! defined(MBEDTLS_DEPRECATED_REMOVED)
int mbedtls_md_init_ctx( mbedtls_md_context_t *ctx, mbedtls_md_handle_t md_info )
{
return mbedtls_md_setup( ctx, md_info, 1 );
}
#endif
int mbedtls_md_setup( mbedtls_md_context_t *ctx, mbedtls_md_handle_t md_info, int hmac )
{
if( md_info == MBEDTLS_MD_INVALID_HANDLE || ctx == NULL )
return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
ctx->md_ctx = mbedtls_md_info_ctx_alloc( md_info );
if( ctx->md_ctx == NULL )
return( MBEDTLS_ERR_MD_ALLOC_FAILED );
if( hmac != 0 )
{
ctx->hmac_ctx = mbedtls_calloc( 2,
mbedtls_md_info_block_size( md_info ) );
if( ctx->hmac_ctx == NULL )
{
mbedtls_md_info_ctx_free( md_info, ctx->md_ctx );
return( MBEDTLS_ERR_MD_ALLOC_FAILED );
}
}
#if !defined(MBEDTLS_MD_SINGLE_HASH)
ctx->md_info = md_info;
#endif
return( 0 );
}
#if !defined(MBEDTLS_MD_SINGLE_HASH)
int mbedtls_md_starts( mbedtls_md_context_t *ctx )
{
return( mbedtls_md_starts_internal( ctx ) );
}
int mbedtls_md_update( mbedtls_md_context_t *ctx,
const unsigned char *input,
size_t ilen )
{
return( mbedtls_md_update_internal( ctx, input, ilen ) );
}
int mbedtls_md_finish( mbedtls_md_context_t *ctx, unsigned char *output )
{
return( mbedtls_md_finish_internal( ctx, output ) );
}
int mbedtls_md( mbedtls_md_handle_t md_info, const unsigned char *input, size_t ilen,
unsigned char *output )
{
return( mbedtls_md_internal( md_info, input, ilen, output ) );
}
#endif /* !MBEDTLS_MD_SINGLE_HASH */
#if defined(MBEDTLS_FS_IO)
int mbedtls_md_file( mbedtls_md_handle_t md_info, const char *path, unsigned char *output )
{
int ret;
FILE *f;
size_t n;
mbedtls_md_context_t ctx;
unsigned char buf[1024];
if( md_info == MBEDTLS_MD_INVALID_HANDLE )
return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
if( ( f = fopen( path, "rb" ) ) == NULL )
return( MBEDTLS_ERR_MD_FILE_IO_ERROR );
mbedtls_md_init( &ctx );
if( ( ret = mbedtls_md_setup( &ctx, md_info, 0 ) ) != 0 )
goto cleanup;
ret = mbedtls_md_info_starts( md_info, ctx.md_ctx );
if( ret != 0 )
goto cleanup;
while( ( n = fread( buf, 1, sizeof( buf ), f ) ) > 0 )
{
ret = mbedtls_md_info_update( md_info, ctx.md_ctx,
buf, n );
if( ret != 0 )
goto cleanup;
}
if( ferror( f ) != 0 )
{
ret = MBEDTLS_ERR_MD_FILE_IO_ERROR;
}
else
{
ret = mbedtls_md_info_finish( md_info, ctx.md_ctx,
output );
}
cleanup:
mbedtls_platform_zeroize( buf, sizeof( buf ) );
fclose( f );
mbedtls_md_free( &ctx );
return( ret );
}
#endif /* MBEDTLS_FS_IO */
int mbedtls_md_hmac_starts( mbedtls_md_context_t *ctx, const unsigned char *key, size_t keylen )
{
int ret;
unsigned char sum[MBEDTLS_MD_MAX_SIZE];
unsigned char *ipad, *opad;
size_t i;
mbedtls_md_handle_t md_info;
if( ctx == NULL || ctx->hmac_ctx == NULL )
return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
md_info = mbedtls_md_get_handle( ctx );
if( md_info == MBEDTLS_MD_INVALID_HANDLE )
return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
if( keylen > (size_t) mbedtls_md_info_block_size( md_info ) )
{
if( ( ret = mbedtls_md_info_starts( md_info, ctx->md_ctx ) ) != 0 )
goto cleanup;
if( ( ret = mbedtls_md_info_update( md_info, ctx->md_ctx,
key, keylen ) ) != 0 )
{
goto cleanup;
}
if( ( ret = mbedtls_md_info_finish( md_info, ctx->md_ctx, sum ) ) != 0 )
goto cleanup;
keylen = mbedtls_md_info_size( md_info );
key = sum;
}
ipad = (unsigned char *) ctx->hmac_ctx;
opad = (unsigned char *) ctx->hmac_ctx +
mbedtls_md_info_block_size( md_info );
memset( ipad, 0x36, mbedtls_md_info_block_size( md_info ) );
memset( opad, 0x5C, mbedtls_md_info_block_size( md_info ) );
for( i = 0; i < keylen; i++ )
{
ipad[i] = (unsigned char)( ipad[i] ^ key[i] );
opad[i] = (unsigned char)( opad[i] ^ key[i] );
}
if( ( ret = mbedtls_md_info_starts( md_info, ctx->md_ctx ) ) != 0 )
goto cleanup;
if( ( ret = mbedtls_md_info_update( md_info, ctx->md_ctx, ipad,
mbedtls_md_info_block_size( md_info ) ) ) != 0 )
{
goto cleanup;
}
cleanup:
mbedtls_platform_zeroize( sum, sizeof( sum ) );
return( ret );
}
int mbedtls_md_hmac_update( mbedtls_md_context_t *ctx,
const unsigned char *input, size_t ilen )
{
mbedtls_md_handle_t md_info;
if( ctx == NULL || ctx->hmac_ctx == NULL )
return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
md_info = mbedtls_md_get_handle( ctx );
if( md_info == MBEDTLS_MD_INVALID_HANDLE )
return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
return( mbedtls_md_info_update( md_info,
ctx->md_ctx, input,
ilen ) );
}
int mbedtls_md_hmac_finish( mbedtls_md_context_t *ctx, unsigned char *output )
{
int ret;
unsigned char tmp[MBEDTLS_MD_MAX_SIZE];
unsigned char *opad;
mbedtls_md_handle_t md_info;
if( ctx == NULL || ctx->hmac_ctx == NULL )
return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
md_info = mbedtls_md_get_handle( ctx );
if( md_info == MBEDTLS_MD_INVALID_HANDLE )
return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
opad = (unsigned char *) ctx->hmac_ctx +
mbedtls_md_info_block_size( md_info );
if( ( ret = mbedtls_md_info_finish( md_info, ctx->md_ctx, tmp ) ) != 0 )
return( ret );
if( ( ret = mbedtls_md_info_starts( md_info, ctx->md_ctx ) ) != 0 )
return( ret );
if( ( ret = mbedtls_md_info_update( md_info, ctx->md_ctx, opad,
mbedtls_md_info_block_size( md_info ) ) ) != 0 )
{
return( ret );
}
if( ( ret = mbedtls_md_info_update( md_info, ctx->md_ctx, tmp,
mbedtls_md_info_size( md_info ) ) ) != 0 )
{
return( ret );
}
if( ( ret = mbedtls_md_info_finish( md_info, ctx->md_ctx, output ) ) != 0 )
return( ret );
return( 0 );
}
int mbedtls_md_hmac_reset( mbedtls_md_context_t *ctx )
{
int ret;
unsigned char *ipad;
mbedtls_md_handle_t md_info;
if( ctx == NULL || ctx->hmac_ctx == NULL )
return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
md_info = mbedtls_md_get_handle( ctx );
if( md_info == MBEDTLS_MD_INVALID_HANDLE )
return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
ipad = (unsigned char *) ctx->hmac_ctx;
ret = mbedtls_md_info_starts( md_info, ctx->md_ctx );
if( ret != 0 )
return( ret );
ret = mbedtls_md_info_update( md_info,
ctx->md_ctx, ipad,
mbedtls_md_info_block_size( md_info ) );
return( ret );
}
int mbedtls_md_hmac( mbedtls_md_handle_t md_info,
const unsigned char *key, size_t keylen,
const unsigned char *input, size_t ilen,
unsigned char *output )
{
mbedtls_md_context_t ctx;
int ret;
if( md_info == MBEDTLS_MD_INVALID_HANDLE )
return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
mbedtls_md_init( &ctx );
if( ( ret = mbedtls_md_setup( &ctx, md_info, 1 ) ) != 0 )
goto cleanup;
if( ( ret = mbedtls_md_hmac_starts( &ctx, key, keylen ) ) != 0 )
goto cleanup;
if( ( ret = mbedtls_md_hmac_update( &ctx, input, ilen ) ) != 0 )
goto cleanup;
if( ( ret = mbedtls_md_hmac_finish( &ctx, output ) ) != 0 )
goto cleanup;
cleanup:
mbedtls_md_free( &ctx );
return( ret );
}
#if !defined(MBEDTLS_MD_SINGLE_HASH)
int mbedtls_md_process( mbedtls_md_context_t *ctx, const unsigned char *data )
{
return( mbedtls_md_process_internal( ctx, data ) );
}
#endif /* !MBEDTLS_MD_SINGLE_HASH */
unsigned char mbedtls_md_get_size( mbedtls_md_handle_t md_info )
{
if( md_info == MBEDTLS_MD_INVALID_HANDLE )
return( 0 );
return mbedtls_md_info_size( md_info );
}
mbedtls_md_type_t mbedtls_md_get_type( mbedtls_md_handle_t md_info )
{
if( md_info == MBEDTLS_MD_INVALID_HANDLE )
return( MBEDTLS_MD_NONE );
return mbedtls_md_info_type( md_info );
}
const char *mbedtls_md_get_name( mbedtls_md_handle_t md_info )
{
if( md_info == MBEDTLS_MD_INVALID_HANDLE )
return( NULL );
return mbedtls_md_info_name( md_info );
}
#endif /* MBEDTLS_MD_C */
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