1 /**
2  * \file mbedtls_md.c
3  *
4  * \brief Generic message digest wrapper for mbed TLS
5  *
6  * \author Adriaan de Jong <dejong@fox-it.com>
7  *
8  *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
9  *  SPDX-License-Identifier: Apache-2.0
10  *
11  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
12  *  not use this file except in compliance with the License.
13  *  You may obtain a copy of the License at
14  *
15  *  http://www.apache.org/licenses/LICENSE-2.0
16  *
17  *  Unless required by applicable law or agreed to in writing, software
18  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
19  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
20  *  See the License for the specific language governing permissions and
21  *  limitations under the License.
22  *
23  *  This file is part of mbed TLS (https://tls.mbed.org)
24  */
25 
26 #if !defined(MBEDTLS_CONFIG_FILE)
27 #include "mbedtls/config.h"
28 #else
29 #include MBEDTLS_CONFIG_FILE
30 #endif
31 
32 #if defined(MBEDTLS_MD_C)
33 
34 #include "mbedtls/md.h"
35 #include "mbedtls/md_internal.h"
36 
37 #if defined(MBEDTLS_PLATFORM_C)
38 #include "mbedtls/platform.h"
39 #else
40 #include <stdlib.h>
41 #define mbedtls_calloc    calloc
42 #define mbedtls_free       free
43 #endif
44 
45 #include <string.h>
46 
47 #if defined(MBEDTLS_FS_IO)
48 #include <stdio.h>
49 #endif
50 
51 /* Implementation that should never be optimized out by the compiler */
mbedtls_zeroize(void * v,size_t n)52 static void mbedtls_zeroize( void *v, size_t n ) {
53     volatile unsigned char *p = v; while( n-- ) *p++ = 0;
54 }
55 
56 /*
57  * Reminder: update profiles in x509_crt.c when adding a new hash!
58  */
59 static const int supported_digests[] = {
60 
61 #if defined(MBEDTLS_SHA512_C)
62         MBEDTLS_MD_SHA512,
63         MBEDTLS_MD_SHA384,
64 #endif
65 
66 #if defined(MBEDTLS_SHA256_C)
67         MBEDTLS_MD_SHA256,
68         MBEDTLS_MD_SHA224,
69 #endif
70 
71 #if defined(MBEDTLS_SHA1_C)
72         MBEDTLS_MD_SHA1,
73 #endif
74 
75 #if defined(MBEDTLS_RIPEMD160_C)
76         MBEDTLS_MD_RIPEMD160,
77 #endif
78 
79 #if defined(MBEDTLS_MD5_C)
80         MBEDTLS_MD_MD5,
81 #endif
82 
83 #if defined(MBEDTLS_MD4_C)
84         MBEDTLS_MD_MD4,
85 #endif
86 
87 #if defined(MBEDTLS_MD2_C)
88         MBEDTLS_MD_MD2,
89 #endif
90 
91         MBEDTLS_MD_NONE
92 };
93 
mbedtls_md_list(void)94 const int *mbedtls_md_list( void )
95 {
96     return( supported_digests );
97 }
98 
mbedtls_md_info_from_string(const char * md_name)99 const mbedtls_md_info_t *mbedtls_md_info_from_string( const char *md_name )
100 {
101     if( NULL == md_name )
102         return( NULL );
103 
104     /* Get the appropriate digest information */
105 #if defined(MBEDTLS_MD2_C)
106     if( !strcmp( "MD2", md_name ) )
107         return mbedtls_md_info_from_type( MBEDTLS_MD_MD2 );
108 #endif
109 #if defined(MBEDTLS_MD4_C)
110     if( !strcmp( "MD4", md_name ) )
111         return mbedtls_md_info_from_type( MBEDTLS_MD_MD4 );
112 #endif
113 #if defined(MBEDTLS_MD5_C)
114     if( !strcmp( "MD5", md_name ) )
115         return mbedtls_md_info_from_type( MBEDTLS_MD_MD5 );
116 #endif
117 #if defined(MBEDTLS_RIPEMD160_C)
118     if( !strcmp( "RIPEMD160", md_name ) )
119         return mbedtls_md_info_from_type( MBEDTLS_MD_RIPEMD160 );
120 #endif
121 #if defined(MBEDTLS_SHA1_C)
122     if( !strcmp( "SHA1", md_name ) || !strcmp( "SHA", md_name ) )
123         return mbedtls_md_info_from_type( MBEDTLS_MD_SHA1 );
124 #endif
125 #if defined(MBEDTLS_SHA256_C)
126     if( !strcmp( "SHA224", md_name ) )
127         return mbedtls_md_info_from_type( MBEDTLS_MD_SHA224 );
128     if( !strcmp( "SHA256", md_name ) )
129         return mbedtls_md_info_from_type( MBEDTLS_MD_SHA256 );
130 #endif
131 #if defined(MBEDTLS_SHA512_C)
132     if( !strcmp( "SHA384", md_name ) )
133         return mbedtls_md_info_from_type( MBEDTLS_MD_SHA384 );
134     if( !strcmp( "SHA512", md_name ) )
135         return mbedtls_md_info_from_type( MBEDTLS_MD_SHA512 );
136 #endif
137     return( NULL );
138 }
139 
mbedtls_md_info_from_type(mbedtls_md_type_t md_type)140 const mbedtls_md_info_t *mbedtls_md_info_from_type( mbedtls_md_type_t md_type )
141 {
142     switch( md_type )
143     {
144 #if defined(MBEDTLS_MD2_C)
145         case MBEDTLS_MD_MD2:
146             return( &mbedtls_md2_info );
147 #endif
148 #if defined(MBEDTLS_MD4_C)
149         case MBEDTLS_MD_MD4:
150             return( &mbedtls_md4_info );
151 #endif
152 #if defined(MBEDTLS_MD5_C)
153         case MBEDTLS_MD_MD5:
154             return( &mbedtls_md5_info );
155 #endif
156 #if defined(MBEDTLS_RIPEMD160_C)
157         case MBEDTLS_MD_RIPEMD160:
158             return( &mbedtls_ripemd160_info );
159 #endif
160 #if defined(MBEDTLS_SHA1_C)
161         case MBEDTLS_MD_SHA1:
162             return( &mbedtls_sha1_info );
163 #endif
164 #if defined(MBEDTLS_SHA256_C)
165         case MBEDTLS_MD_SHA224:
166             return( &mbedtls_sha224_info );
167         case MBEDTLS_MD_SHA256:
168             return( &mbedtls_sha256_info );
169 #endif
170 #if defined(MBEDTLS_SHA512_C)
171         case MBEDTLS_MD_SHA384:
172             return( &mbedtls_sha384_info );
173         case MBEDTLS_MD_SHA512:
174             return( &mbedtls_sha512_info );
175 #endif
176         default:
177             return( NULL );
178     }
179 }
180 
mbedtls_md_init(mbedtls_md_context_t * ctx)181 void mbedtls_md_init( mbedtls_md_context_t *ctx )
182 {
183     memset( ctx, 0, sizeof( mbedtls_md_context_t ) );
184 }
185 
mbedtls_md_free(mbedtls_md_context_t * ctx)186 void mbedtls_md_free( mbedtls_md_context_t *ctx )
187 {
188     if( ctx == NULL || ctx->md_info == NULL )
189         return;
190 
191     if( ctx->md_ctx != NULL )
192         ctx->md_info->ctx_free_func( ctx->md_ctx );
193 
194     if( ctx->hmac_ctx != NULL )
195     {
196         mbedtls_zeroize( ctx->hmac_ctx, 2 * ctx->md_info->block_size );
197         mbedtls_free( ctx->hmac_ctx );
198     }
199 
200     mbedtls_zeroize( ctx, sizeof( mbedtls_md_context_t ) );
201 }
202 
mbedtls_md_clone(mbedtls_md_context_t * dst,const mbedtls_md_context_t * src)203 int mbedtls_md_clone( mbedtls_md_context_t *dst,
204                       const mbedtls_md_context_t *src )
205 {
206     if( dst == NULL || dst->md_info == NULL ||
207         src == NULL || src->md_info == NULL ||
208         dst->md_info != src->md_info )
209     {
210         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
211     }
212 
213     dst->md_info->clone_func( dst->md_ctx, src->md_ctx );
214 
215     return( 0 );
216 }
217 
218 #if ! defined(MBEDTLS_DEPRECATED_REMOVED)
mbedtls_md_init_ctx(mbedtls_md_context_t * ctx,const mbedtls_md_info_t * md_info)219 int mbedtls_md_init_ctx( mbedtls_md_context_t *ctx, const mbedtls_md_info_t *md_info )
220 {
221     return mbedtls_md_setup( ctx, md_info, 1 );
222 }
223 #endif
224 
mbedtls_md_setup(mbedtls_md_context_t * ctx,const mbedtls_md_info_t * md_info,int hmac)225 int mbedtls_md_setup( mbedtls_md_context_t *ctx, const mbedtls_md_info_t *md_info, int hmac )
226 {
227     if( md_info == NULL || ctx == NULL )
228         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
229 
230     if( ( ctx->md_ctx = md_info->ctx_alloc_func() ) == NULL )
231         return( MBEDTLS_ERR_MD_ALLOC_FAILED );
232 
233     if( hmac != 0 )
234     {
235         ctx->hmac_ctx = mbedtls_calloc( 2, md_info->block_size );
236         if( ctx->hmac_ctx == NULL )
237         {
238             md_info->ctx_free_func( ctx->md_ctx );
239             return( MBEDTLS_ERR_MD_ALLOC_FAILED );
240         }
241     }
242 
243     ctx->md_info = md_info;
244 
245     return( 0 );
246 }
247 
mbedtls_md_starts(mbedtls_md_context_t * ctx)248 int mbedtls_md_starts( mbedtls_md_context_t *ctx )
249 {
250     if( ctx == NULL || ctx->md_info == NULL )
251         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
252 
253     ctx->md_info->starts_func( ctx->md_ctx );
254 
255     return( 0 );
256 }
257 
mbedtls_md_update(mbedtls_md_context_t * ctx,const unsigned char * input,size_t ilen)258 int mbedtls_md_update( mbedtls_md_context_t *ctx, const unsigned char *input, size_t ilen )
259 {
260     if( ctx == NULL || ctx->md_info == NULL )
261         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
262 
263     ctx->md_info->update_func( ctx->md_ctx, input, ilen );
264 
265     return( 0 );
266 }
267 
mbedtls_md_finish(mbedtls_md_context_t * ctx,unsigned char * output)268 int mbedtls_md_finish( mbedtls_md_context_t *ctx, unsigned char *output )
269 {
270     if( ctx == NULL || ctx->md_info == NULL )
271         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
272 
273     ctx->md_info->finish_func( ctx->md_ctx, output );
274 
275     return( 0 );
276 }
277 
mbedtls_md(const mbedtls_md_info_t * md_info,const unsigned char * input,size_t ilen,unsigned char * output)278 int mbedtls_md( const mbedtls_md_info_t *md_info, const unsigned char *input, size_t ilen,
279             unsigned char *output )
280 {
281     if( md_info == NULL )
282         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
283 
284     md_info->digest_func( input, ilen, output );
285 
286     return( 0 );
287 }
288 
289 #if defined(MBEDTLS_FS_IO)
mbedtls_md_file(const mbedtls_md_info_t * md_info,const char * path,unsigned char * output)290 int mbedtls_md_file( const mbedtls_md_info_t *md_info, const char *path, unsigned char *output )
291 {
292     int ret;
293     FILE *f;
294     size_t n;
295     mbedtls_md_context_t ctx;
296     unsigned char buf[1024];
297 
298     if( md_info == NULL )
299         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
300 
301     if( ( f = fopen( path, "rb" ) ) == NULL )
302         return( MBEDTLS_ERR_MD_FILE_IO_ERROR );
303 
304     mbedtls_md_init( &ctx );
305 
306     if( ( ret = mbedtls_md_setup( &ctx, md_info, 0 ) ) != 0 )
307         goto cleanup;
308 
309     md_info->starts_func( ctx.md_ctx );
310 
311     while( ( n = fread( buf, 1, sizeof( buf ), f ) ) > 0 )
312         md_info->update_func( ctx.md_ctx, buf, n );
313 
314     if( ferror( f ) != 0 )
315     {
316         ret = MBEDTLS_ERR_MD_FILE_IO_ERROR;
317         goto cleanup;
318     }
319 
320     md_info->finish_func( ctx.md_ctx, output );
321 
322 cleanup:
323     fclose( f );
324     mbedtls_md_free( &ctx );
325 
326     return( ret );
327 }
328 #endif /* MBEDTLS_FS_IO */
329 
mbedtls_md_hmac_starts(mbedtls_md_context_t * ctx,const unsigned char * key,size_t keylen)330 int mbedtls_md_hmac_starts( mbedtls_md_context_t *ctx, const unsigned char *key, size_t keylen )
331 {
332     unsigned char sum[MBEDTLS_MD_MAX_SIZE];
333     unsigned char *ipad, *opad;
334     size_t i;
335 
336     if( ctx == NULL || ctx->md_info == NULL || ctx->hmac_ctx == NULL )
337         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
338 
339     if( keylen > (size_t) ctx->md_info->block_size )
340     {
341         ctx->md_info->starts_func( ctx->md_ctx );
342         ctx->md_info->update_func( ctx->md_ctx, key, keylen );
343         ctx->md_info->finish_func( ctx->md_ctx, sum );
344 
345         keylen = ctx->md_info->size;
346         key = sum;
347     }
348 
349     ipad = (unsigned char *) ctx->hmac_ctx;
350     opad = (unsigned char *) ctx->hmac_ctx + ctx->md_info->block_size;
351 
352     memset( ipad, 0x36, ctx->md_info->block_size );
353     memset( opad, 0x5C, ctx->md_info->block_size );
354 
355     for( i = 0; i < keylen; i++ )
356     {
357         ipad[i] = (unsigned char)( ipad[i] ^ key[i] );
358         opad[i] = (unsigned char)( opad[i] ^ key[i] );
359     }
360 
361     mbedtls_zeroize( sum, sizeof( sum ) );
362 
363     ctx->md_info->starts_func( ctx->md_ctx );
364     ctx->md_info->update_func( ctx->md_ctx, ipad, ctx->md_info->block_size );
365 
366     return( 0 );
367 }
368 
mbedtls_md_hmac_update(mbedtls_md_context_t * ctx,const unsigned char * input,size_t ilen)369 int mbedtls_md_hmac_update( mbedtls_md_context_t *ctx, const unsigned char *input, size_t ilen )
370 {
371     if( ctx == NULL || ctx->md_info == NULL || ctx->hmac_ctx == NULL )
372         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
373 
374     ctx->md_info->update_func( ctx->md_ctx, input, ilen );
375 
376     return( 0 );
377 }
378 
mbedtls_md_hmac_finish(mbedtls_md_context_t * ctx,unsigned char * output)379 int mbedtls_md_hmac_finish( mbedtls_md_context_t *ctx, unsigned char *output )
380 {
381     unsigned char tmp[MBEDTLS_MD_MAX_SIZE];
382     unsigned char *opad;
383 
384     if( ctx == NULL || ctx->md_info == NULL || ctx->hmac_ctx == NULL )
385         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
386 
387     opad = (unsigned char *) ctx->hmac_ctx + ctx->md_info->block_size;
388 
389     ctx->md_info->finish_func( ctx->md_ctx, tmp );
390     ctx->md_info->starts_func( ctx->md_ctx );
391     ctx->md_info->update_func( ctx->md_ctx, opad, ctx->md_info->block_size );
392     ctx->md_info->update_func( ctx->md_ctx, tmp, ctx->md_info->size );
393     ctx->md_info->finish_func( ctx->md_ctx, output );
394 
395     return( 0 );
396 }
397 
mbedtls_md_hmac_reset(mbedtls_md_context_t * ctx)398 int mbedtls_md_hmac_reset( mbedtls_md_context_t *ctx )
399 {
400     unsigned char *ipad;
401 
402     if( ctx == NULL || ctx->md_info == NULL || ctx->hmac_ctx == NULL )
403         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
404 
405     ipad = (unsigned char *) ctx->hmac_ctx;
406 
407     ctx->md_info->starts_func( ctx->md_ctx );
408     ctx->md_info->update_func( ctx->md_ctx, ipad, ctx->md_info->block_size );
409 
410     return( 0 );
411 }
412 
mbedtls_md_hmac(const mbedtls_md_info_t * md_info,const unsigned char * key,size_t keylen,const unsigned char * input,size_t ilen,unsigned char * output)413 int mbedtls_md_hmac( const mbedtls_md_info_t *md_info, const unsigned char *key, size_t keylen,
414                 const unsigned char *input, size_t ilen,
415                 unsigned char *output )
416 {
417     mbedtls_md_context_t ctx;
418     int ret;
419 
420     if( md_info == NULL )
421         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
422 
423     mbedtls_md_init( &ctx );
424 
425     if( ( ret = mbedtls_md_setup( &ctx, md_info, 1 ) ) != 0 )
426         return( ret );
427 
428     mbedtls_md_hmac_starts( &ctx, key, keylen );
429     mbedtls_md_hmac_update( &ctx, input, ilen );
430     mbedtls_md_hmac_finish( &ctx, output );
431 
432     mbedtls_md_free( &ctx );
433 
434     return( 0 );
435 }
436 
mbedtls_md_process(mbedtls_md_context_t * ctx,const unsigned char * data)437 int mbedtls_md_process( mbedtls_md_context_t *ctx, const unsigned char *data )
438 {
439     if( ctx == NULL || ctx->md_info == NULL )
440         return( MBEDTLS_ERR_MD_BAD_INPUT_DATA );
441 
442     ctx->md_info->process_func( ctx->md_ctx, data );
443 
444     return( 0 );
445 }
446 
mbedtls_md_get_size(const mbedtls_md_info_t * md_info)447 unsigned char mbedtls_md_get_size( const mbedtls_md_info_t *md_info )
448 {
449     if( md_info == NULL )
450         return( 0 );
451 
452     return md_info->size;
453 }
454 
mbedtls_md_get_type(const mbedtls_md_info_t * md_info)455 mbedtls_md_type_t mbedtls_md_get_type( const mbedtls_md_info_t *md_info )
456 {
457     if( md_info == NULL )
458         return( MBEDTLS_MD_NONE );
459 
460     return md_info->type;
461 }
462 
mbedtls_md_get_name(const mbedtls_md_info_t * md_info)463 const char *mbedtls_md_get_name( const mbedtls_md_info_t *md_info )
464 {
465     if( md_info == NULL )
466         return( NULL );
467 
468     return md_info->name;
469 }
470 
471 #endif /* MBEDTLS_MD_C */
472