md.c

00001 /**
00002  * \file mbedtls_md.c
00003  *
00004  * \brief Generic message digest wrapper for mbed TLS
00005  *
00006  * \author Adriaan de Jong <dejong@fox-it.com>
00007  *
00008  *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
00009  *  SPDX-License-Identifier: Apache-2.0
00010  *
00011  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
00012  *  not use this file except in compliance with the License.
00013  *  You may obtain a copy of the License at
00014  *
00015  *  http://www.apache.org/licenses/LICENSE-2.0
00016  *
00017  *  Unless required by applicable law or agreed to in writing, software
00018  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
00019  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00020  *  See the License for the specific language governing permissions and
00021  *  limitations under the License.
00022  *
00023  *  This file is part of mbed TLS (https://tls.mbed.org)
00024  */
00025 
00026 #if !defined(MBEDTLS_CONFIG_FILE)
00027 #include "mbedtls/config.h"
00028 #else
00029 #include MBEDTLS_CONFIG_FILE
00030 #endif
00031 
00032 #if defined(MBEDTLS_MD_C)
00033 
00034 #include "mbedtls/md.h"
00035 #include "mbedtls/md_internal.h"
00036 
00037 #if defined(MBEDTLS_PLATFORM_C)
00038 #include "mbedtls/platform.h"
00039 #else
00040 #include <stdlib.h>
00041 #define mbedtls_calloc    calloc
00042 #define mbedtls_free       free
00043 #endif
00044 
00045 #include <string.h>
00046 
00047 #if defined(MBEDTLS_FS_IO)
00048 #include <stdio.h>
00049 #endif
00050 
00051 /* Implementation that should never be optimized out by the compiler */
00052 static void mbedtls_zeroize( void *v, size_t n ) {
00053     volatile unsigned char *p = v; while( n-- ) *p++ = 0;
00054 }
00055 
00056 /*
00057  * Reminder: update profiles in x509_crt.c when adding a new hash!
00058  */
00059 static const int supported_digests[] = {
00060 
00061 #if defined(MBEDTLS_SHA512_C)
00062         MBEDTLS_MD_SHA512,
00063         MBEDTLS_MD_SHA384,
00064 #endif
00065 
00066 #if defined(MBEDTLS_SHA256_C)
00067         MBEDTLS_MD_SHA256,
00068         MBEDTLS_MD_SHA224,
00069 #endif
00070 
00071 #if defined(MBEDTLS_SHA1_C)
00072         MBEDTLS_MD_SHA1,
00073 #endif
00074 
00075 #if defined(MBEDTLS_RIPEMD160_C)
00076         MBEDTLS_MD_RIPEMD160,
00077 #endif
00078 
00079 #if defined(MBEDTLS_MD5_C)
00080         MBEDTLS_MD_MD5,
00081 #endif
00082 
00083 #if defined(MBEDTLS_MD4_C)
00084         MBEDTLS_MD_MD4,
00085 #endif
00086 
00087 #if defined(MBEDTLS_MD2_C)
00088         MBEDTLS_MD_MD2,
00089 #endif
00090 
00091         MBEDTLS_MD_NONE
00092 };
00093 
00094 const int *mbedtls_md_list( void )
00095 {
00096     return( supported_digests );
00097 }
00098 
00099 const mbedtls_md_info_t *mbedtls_md_info_from_string( const char *md_name )
00100 {
00101     if( NULL == md_name )
00102         return( NULL );
00103 
00104     /* Get the appropriate digest information */
00105 #if defined(MBEDTLS_MD2_C)
00106     if( !strcmp( "MD2", md_name ) )
00107         return mbedtls_md_info_from_type( MBEDTLS_MD_MD2 );
00108 #endif
00109 #if defined(MBEDTLS_MD4_C)
00110     if( !strcmp( "MD4", md_name ) )
00111         return mbedtls_md_info_from_type( MBEDTLS_MD_MD4 );
00112 #endif
00113 #if defined(MBEDTLS_MD5_C)
00114     if( !strcmp( "MD5", md_name ) )
00115         return mbedtls_md_info_from_type( MBEDTLS_MD_MD5 );
00116 #endif
00117 #if defined(MBEDTLS_RIPEMD160_C)
00118     if( !strcmp( "RIPEMD160", md_name ) )
00119         return mbedtls_md_info_from_type( MBEDTLS_MD_RIPEMD160 );
00120 #endif
00121 #if defined(MBEDTLS_SHA1_C)
00122     if( !strcmp( "SHA1", md_name ) || !strcmp( "SHA", md_name ) )
00123         return mbedtls_md_info_from_type( MBEDTLS_MD_SHA1 );
00124 #endif
00125 #if defined(MBEDTLS_SHA256_C)
00126     if( !strcmp( "SHA224", md_name ) )
00127         return mbedtls_md_info_from_type( MBEDTLS_MD_SHA224 );
00128     if( !strcmp( "SHA256", md_name ) )
00129         return mbedtls_md_info_from_type( MBEDTLS_MD_SHA256 );
00130 #endif
00131 #if defined(MBEDTLS_SHA512_C)
00132     if( !strcmp( "SHA384", md_name ) )
00133         return mbedtls_md_info_from_type( MBEDTLS_MD_SHA384 );
00134     if( !strcmp( "SHA512", md_name ) )
00135         return mbedtls_md_info_from_type( MBEDTLS_MD_SHA512 );
00136 #endif
00137     return( NULL );
00138 }
00139 
00140 const mbedtls_md_info_t *mbedtls_md_info_from_type( mbedtls_md_type_t md_type )
00141 {
00142     switch( md_type )
00143     {
00144 #if defined(MBEDTLS_MD2_C)
00145         case MBEDTLS_MD_MD2:
00146             return( &mbedtls_md2_info );
00147 #endif
00148 #if defined(MBEDTLS_MD4_C)
00149         case MBEDTLS_MD_MD4:
00150             return( &mbedtls_md4_info );
00151 #endif
00152 #if defined(MBEDTLS_MD5_C)
00153         case MBEDTLS_MD_MD5:
00154             return( &mbedtls_md5_info );
00155 #endif
00156 #if defined(MBEDTLS_RIPEMD160_C)
00157         case MBEDTLS_MD_RIPEMD160:
00158             return( &mbedtls_ripemd160_info );
00159 #endif
00160 #if defined(MBEDTLS_SHA1_C)
00161         case MBEDTLS_MD_SHA1:
00162             return( &mbedtls_sha1_info );
00163 #endif
00164 #if defined(MBEDTLS_SHA256_C)
00165         case MBEDTLS_MD_SHA224:
00166             return( &mbedtls_sha224_info );
00167         case MBEDTLS_MD_SHA256:
00168             return( &mbedtls_sha256_info );
00169 #endif
00170 #if defined(MBEDTLS_SHA512_C)
00171         case MBEDTLS_MD_SHA384:
00172             return( &mbedtls_sha384_info );
00173         case MBEDTLS_MD_SHA512:
00174             return( &mbedtls_sha512_info );
00175 #endif
00176         default:
00177             return( NULL );
00178     }
00179 }
00180 
00181 void mbedtls_md_init( mbedtls_md_context_t *ctx )
00182 {
00183     memset( ctx, 0, sizeof( mbedtls_md_context_t ) );
00184 }
00185 
00186 void mbedtls_md_free( mbedtls_md_context_t *ctx )
00187 {
00188     if( ctx == NULL || ctx->md_info == NULL )
00189         return;
00190 
00191     if( ctx->md_ctx != NULL )
00192         ctx->md_info->ctx_free_func( ctx->md_ctx );
00193 
00194     if( ctx->hmac_ctx != NULL )
00195     {
00196         mbedtls_zeroize( ctx->hmac_ctx, 2 * ctx->md_info->block_size );
00197         mbedtls_free( ctx->hmac_ctx );
00198     }
00199 
00200     mbedtls_zeroize( ctx, sizeof( mbedtls_md_context_t ) );
00201 }
00202 
00203 int mbedtls_md_clone( mbedtls_md_context_t *dst,
00204                       const mbedtls_md_context_t *src )
00205 {
00206     if( dst == NULL || dst->md_info == NULL ||
00207         src == NULL || src->md_info == NULL ||
00208         dst->md_info != src->md_info )
00209     {
00210         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
00211     }
00212 
00213     dst->md_info->clone_func( dst->md_ctx, src->md_ctx );
00214 
00215     return( 0 );
00216 }
00217 
00218 #if ! defined(MBEDTLS_DEPRECATED_REMOVED)
00219 int mbedtls_md_init_ctx( mbedtls_md_context_t *ctx, const mbedtls_md_info_t *md_info )
00220 {
00221     return mbedtls_md_setup( ctx, md_info, 1 );
00222 }
00223 #endif
00224 
00225 int mbedtls_md_setup( mbedtls_md_context_t *ctx, const mbedtls_md_info_t *md_info, int hmac )
00226 {
00227     if( md_info == NULL || ctx == NULL )
00228         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
00229 
00230     if( ( ctx->md_ctx = md_info->ctx_alloc_func() ) == NULL )
00231         return( MBEDTLS_ERR_MD_ALLOC_FAILED );
00232 
00233     if( hmac != 0 )
00234     {
00235         ctx->hmac_ctx = mbedtls_calloc( 2, md_info->block_size );
00236         if( ctx->hmac_ctx == NULL )
00237         {
00238             md_info->ctx_free_func( ctx->md_ctx );
00239             return( MBEDTLS_ERR_MD_ALLOC_FAILED );
00240         }
00241     }
00242 
00243     ctx->md_info = md_info;
00244 
00245     return( 0 );
00246 }
00247 
00248 int mbedtls_md_starts( mbedtls_md_context_t *ctx )
00249 {
00250     if( ctx == NULL || ctx->md_info == NULL )
00251         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
00252 
00253     ctx->md_info->starts_func( ctx->md_ctx );
00254 
00255     return( 0 );
00256 }
00257 
00258 int mbedtls_md_update( mbedtls_md_context_t *ctx, const unsigned char *input, size_t ilen )
00259 {
00260     if( ctx == NULL || ctx->md_info == NULL )
00261         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
00262 
00263     ctx->md_info->update_func( ctx->md_ctx, input, ilen );
00264 
00265     return( 0 );
00266 }
00267 
00268 int mbedtls_md_finish( mbedtls_md_context_t *ctx, unsigned char *output )
00269 {
00270     if( ctx == NULL || ctx->md_info == NULL )
00271         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
00272 
00273     ctx->md_info->finish_func( ctx->md_ctx, output );
00274 
00275     return( 0 );
00276 }
00277 
00278 int mbedtls_md( const mbedtls_md_info_t *md_info, const unsigned char *input, size_t ilen,
00279             unsigned char *output )
00280 {
00281     if( md_info == NULL )
00282         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
00283 
00284     md_info->digest_func( input, ilen, output );
00285 
00286     return( 0 );
00287 }
00288 
00289 #if defined(MBEDTLS_FS_IO)
00290 int mbedtls_md_file( const mbedtls_md_info_t *md_info, const char *path, unsigned char *output )
00291 {
00292     int ret;
00293     FILE *f;
00294     size_t n;
00295     mbedtls_md_context_t ctx;
00296     unsigned char buf[1024];
00297 
00298     if( md_info == NULL )
00299         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
00300 
00301     if( ( f = fopen( path, "rb" ) ) == NULL )
00302         return( MBEDTLS_ERR_MD_FILE_IO_ERROR );
00303 
00304     mbedtls_md_init( &ctx );
00305 
00306     if( ( ret = mbedtls_md_setup( &ctx, md_info, 0 ) ) != 0 )
00307         goto cleanup;
00308 
00309     md_info->starts_func( ctx.md_ctx );
00310 
00311     while( ( n = fread( buf, 1, sizeof( buf ), f ) ) > 0 )
00312         md_info->update_func( ctx.md_ctx, buf, n );
00313 
00314     if( ferror( f ) != 0 )
00315     {
00316         ret = MBEDTLS_ERR_MD_FILE_IO_ERROR;
00317         goto cleanup;
00318     }
00319 
00320     md_info->finish_func( ctx.md_ctx, output );
00321 
00322 cleanup:
00323     fclose( f );
00324     mbedtls_md_free( &ctx );
00325 
00326     return( ret );
00327 }
00328 #endif /* MBEDTLS_FS_IO */
00329 
00330 int mbedtls_md_hmac_starts( mbedtls_md_context_t *ctx, const unsigned char *key, size_t keylen )
00331 {
00332     unsigned char sum[MBEDTLS_MD_MAX_SIZE];
00333     unsigned char *ipad, *opad;
00334     size_t i;
00335 
00336     if( ctx == NULL || ctx->md_info == NULL || ctx->hmac_ctx == NULL )
00337         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
00338 
00339     if( keylen > (size_t) ctx->md_info->block_size )
00340     {
00341         ctx->md_info->starts_func( ctx->md_ctx );
00342         ctx->md_info->update_func( ctx->md_ctx, key, keylen );
00343         ctx->md_info->finish_func( ctx->md_ctx, sum );
00344 
00345         keylen = ctx->md_info->size;
00346         key = sum;
00347     }
00348 
00349     ipad = (unsigned char *) ctx->hmac_ctx;
00350     opad = (unsigned char *) ctx->hmac_ctx + ctx->md_info->block_size;
00351 
00352     memset( ipad, 0x36, ctx->md_info->block_size );
00353     memset( opad, 0x5C, ctx->md_info->block_size );
00354 
00355     for( i = 0; i < keylen; i++ )
00356     {
00357         ipad[i] = (unsigned char)( ipad[i] ^ key[i] );
00358         opad[i] = (unsigned char)( opad[i] ^ key[i] );
00359     }
00360 
00361     mbedtls_zeroize( sum, sizeof( sum ) );
00362 
00363     ctx->md_info->starts_func( ctx->md_ctx );
00364     ctx->md_info->update_func( ctx->md_ctx, ipad, ctx->md_info->block_size );
00365 
00366     return( 0 );
00367 }
00368 
00369 int mbedtls_md_hmac_update( mbedtls_md_context_t *ctx, const unsigned char *input, size_t ilen )
00370 {
00371     if( ctx == NULL || ctx->md_info == NULL || ctx->hmac_ctx == NULL )
00372         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
00373 
00374     ctx->md_info->update_func( ctx->md_ctx, input, ilen );
00375 
00376     return( 0 );
00377 }
00378 
00379 int mbedtls_md_hmac_finish( mbedtls_md_context_t *ctx, unsigned char *output )
00380 {
00381     unsigned char tmp[MBEDTLS_MD_MAX_SIZE];
00382     unsigned char *opad;
00383 
00384     if( ctx == NULL || ctx->md_info == NULL || ctx->hmac_ctx == NULL )
00385         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
00386 
00387     opad = (unsigned char *) ctx->hmac_ctx + ctx->md_info->block_size;
00388 
00389     ctx->md_info->finish_func( ctx->md_ctx, tmp );
00390     ctx->md_info->starts_func( ctx->md_ctx );
00391     ctx->md_info->update_func( ctx->md_ctx, opad, ctx->md_info->block_size );
00392     ctx->md_info->update_func( ctx->md_ctx, tmp, ctx->md_info->size );
00393     ctx->md_info->finish_func( ctx->md_ctx, output );
00394 
00395     return( 0 );
00396 }
00397 
00398 int mbedtls_md_hmac_reset( mbedtls_md_context_t *ctx )
00399 {
00400     unsigned char *ipad;
00401 
00402     if( ctx == NULL || ctx->md_info == NULL || ctx->hmac_ctx == NULL )
00403         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
00404 
00405     ipad = (unsigned char *) ctx->hmac_ctx;
00406 
00407     ctx->md_info->starts_func( ctx->md_ctx );
00408     ctx->md_info->update_func( ctx->md_ctx, ipad, ctx->md_info->block_size );
00409 
00410     return( 0 );
00411 }
00412 
00413 int mbedtls_md_hmac( const mbedtls_md_info_t *md_info, const unsigned char *key, size_t keylen,
00414                 const unsigned char *input, size_t ilen,
00415                 unsigned char *output )
00416 {
00417     mbedtls_md_context_t ctx;
00418     int ret;
00419 
00420     if( md_info == NULL )
00421         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
00422 
00423     mbedtls_md_init( &ctx );
00424 
00425     if( ( ret = mbedtls_md_setup( &ctx, md_info, 1 ) ) != 0 )
00426         return( ret );
00427 
00428     mbedtls_md_hmac_starts( &ctx, key, keylen );
00429     mbedtls_md_hmac_update( &ctx, input, ilen );
00430     mbedtls_md_hmac_finish( &ctx, output );
00431 
00432     mbedtls_md_free( &ctx );
00433 
00434     return( 0 );
00435 }
00436 
00437 int mbedtls_md_process( mbedtls_md_context_t *ctx, const unsigned char *data )
00438 {
00439     if( ctx == NULL || ctx->md_info == NULL )
00440         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
00441 
00442     ctx->md_info->process_func( ctx->md_ctx, data );
00443 
00444     return( 0 );
00445 }
00446 
00447 unsigned char mbedtls_md_get_size( const mbedtls_md_info_t *md_info )
00448 {
00449     if( md_info == NULL )
00450         return( 0 );
00451 
00452     return md_info->size;
00453 }
00454 
00455 mbedtls_md_type_t mbedtls_md_get_type( const mbedtls_md_info_t *md_info )
00456 {
00457     if( md_info == NULL )
00458         return( MBEDTLS_MD_NONE );
00459 
00460     return md_info->type;
00461 }
00462 
00463 const char *mbedtls_md_get_name( const mbedtls_md_info_t *md_info )
00464 {
00465     if( md_info == NULL )
00466         return( NULL );
00467 
00468     return md_info->name;
00469 }
00470 
00471 #endif /* MBEDTLS_MD_C */