1 /**
2 * \file pkcs5.c
3 *
4 * \brief PKCS#5 functions
5 *
6 * \author Mathias Olsson <mathias@kompetensum.com>
7 *
8 * Copyright The Mbed TLS Contributors
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 /*
24 * PKCS#5 includes PBKDF2 and more
25 *
26 * http://tools.ietf.org/html/rfc2898 (Specification)
27 * http://tools.ietf.org/html/rfc6070 (Test vectors)
28 */
29
30 #include "common.h"
31
32 #if defined(MBEDTLS_PKCS5_C)
33
34 #include "mbedtls/pkcs5.h"
35 #include "mbedtls/error.h"
36
37 #if defined(MBEDTLS_ASN1_PARSE_C)
38 #include "mbedtls/asn1.h"
39 #include "mbedtls/cipher.h"
40 #include "mbedtls/oid.h"
41 #endif /* MBEDTLS_ASN1_PARSE_C */
42
43 #include <string.h>
44
45 #if defined(MBEDTLS_PLATFORM_C)
46 #include "mbedtls/platform.h"
47 #else
48 #include <stdio.h>
49 #define mbedtls_printf printf
50 #endif
51
52 #if defined(MBEDTLS_ASN1_PARSE_C)
pkcs5_parse_pbkdf2_params(const mbedtls_asn1_buf * params,mbedtls_asn1_buf * salt,int * iterations,int * keylen,mbedtls_md_type_t * md_type)53 static int pkcs5_parse_pbkdf2_params( const mbedtls_asn1_buf *params,
54 mbedtls_asn1_buf *salt, int *iterations,
55 int *keylen, mbedtls_md_type_t *md_type )
56 {
57 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
58 mbedtls_asn1_buf prf_alg_oid;
59 unsigned char *p = params->p;
60 const unsigned char *end = params->p + params->len;
61
62 if( params->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) )
63 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_PKCS5_INVALID_FORMAT,
64 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) );
65 /*
66 * PBKDF2-params ::= SEQUENCE {
67 * salt OCTET STRING,
68 * iterationCount INTEGER,
69 * keyLength INTEGER OPTIONAL
70 * prf AlgorithmIdentifier DEFAULT algid-hmacWithSHA1
71 * }
72 *
73 */
74 if( ( ret = mbedtls_asn1_get_tag( &p, end, &salt->len,
75 MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
76 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_PKCS5_INVALID_FORMAT, ret ) );
77
78 salt->p = p;
79 p += salt->len;
80
81 if( ( ret = mbedtls_asn1_get_int( &p, end, iterations ) ) != 0 )
82 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_PKCS5_INVALID_FORMAT, ret ) );
83
84 if( p == end )
85 return( 0 );
86
87 if( ( ret = mbedtls_asn1_get_int( &p, end, keylen ) ) != 0 )
88 {
89 if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
90 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_PKCS5_INVALID_FORMAT, ret ) );
91 }
92
93 if( p == end )
94 return( 0 );
95
96 if( ( ret = mbedtls_asn1_get_alg_null( &p, end, &prf_alg_oid ) ) != 0 )
97 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_PKCS5_INVALID_FORMAT, ret ) );
98
99 if( mbedtls_oid_get_md_hmac( &prf_alg_oid, md_type ) != 0 )
100 return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );
101
102 if( p != end )
103 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_PKCS5_INVALID_FORMAT,
104 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
105
106 return( 0 );
107 }
108
mbedtls_pkcs5_pbes2(const mbedtls_asn1_buf * pbe_params,int mode,const unsigned char * pwd,size_t pwdlen,const unsigned char * data,size_t datalen,unsigned char * output)109 int mbedtls_pkcs5_pbes2( const mbedtls_asn1_buf *pbe_params, int mode,
110 const unsigned char *pwd, size_t pwdlen,
111 const unsigned char *data, size_t datalen,
112 unsigned char *output )
113 {
114 int ret, iterations = 0, keylen = 0;
115 unsigned char *p, *end;
116 mbedtls_asn1_buf kdf_alg_oid, enc_scheme_oid, kdf_alg_params, enc_scheme_params;
117 mbedtls_asn1_buf salt;
118 mbedtls_md_type_t md_type = MBEDTLS_MD_SHA1;
119 unsigned char key[32], iv[32];
120 size_t olen = 0;
121 const mbedtls_md_info_t *md_info;
122 const mbedtls_cipher_info_t *cipher_info;
123 mbedtls_md_context_t md_ctx;
124 mbedtls_cipher_type_t cipher_alg;
125 mbedtls_cipher_context_t cipher_ctx;
126
127 p = pbe_params->p;
128 end = p + pbe_params->len;
129
130 /*
131 * PBES2-params ::= SEQUENCE {
132 * keyDerivationFunc AlgorithmIdentifier {{PBES2-KDFs}},
133 * encryptionScheme AlgorithmIdentifier {{PBES2-Encs}}
134 * }
135 */
136 if( pbe_params->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) )
137 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_PKCS5_INVALID_FORMAT,
138 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) );
139
140 if( ( ret = mbedtls_asn1_get_alg( &p, end, &kdf_alg_oid,
141 &kdf_alg_params ) ) != 0 )
142 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_PKCS5_INVALID_FORMAT, ret ) );
143
144 // Only PBKDF2 supported at the moment
145 //
146 if( MBEDTLS_OID_CMP( MBEDTLS_OID_PKCS5_PBKDF2, &kdf_alg_oid ) != 0 )
147 return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );
148
149 if( ( ret = pkcs5_parse_pbkdf2_params( &kdf_alg_params,
150 &salt, &iterations, &keylen,
151 &md_type ) ) != 0 )
152 {
153 return( ret );
154 }
155
156 md_info = mbedtls_md_info_from_type( md_type );
157 if( md_info == NULL )
158 return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );
159
160 if( ( ret = mbedtls_asn1_get_alg( &p, end, &enc_scheme_oid,
161 &enc_scheme_params ) ) != 0 )
162 {
163 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_PKCS5_INVALID_FORMAT, ret ) );
164 }
165
166 if( mbedtls_oid_get_cipher_alg( &enc_scheme_oid, &cipher_alg ) != 0 )
167 return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );
168
169 cipher_info = mbedtls_cipher_info_from_type( cipher_alg );
170 if( cipher_info == NULL )
171 return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );
172
173 /*
174 * The value of keylen from pkcs5_parse_pbkdf2_params() is ignored
175 * since it is optional and we don't know if it was set or not
176 */
177 keylen = cipher_info->key_bitlen / 8;
178
179 if( enc_scheme_params.tag != MBEDTLS_ASN1_OCTET_STRING ||
180 enc_scheme_params.len != cipher_info->iv_size )
181 {
182 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT );
183 }
184
185 mbedtls_md_init( &md_ctx );
186 mbedtls_cipher_init( &cipher_ctx );
187
188 memcpy( iv, enc_scheme_params.p, enc_scheme_params.len );
189
190 if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 1 ) ) != 0 )
191 goto exit;
192
193 if( ( ret = mbedtls_pkcs5_pbkdf2_hmac( &md_ctx, pwd, pwdlen, salt.p, salt.len,
194 iterations, keylen, key ) ) != 0 )
195 {
196 goto exit;
197 }
198
199 if( ( ret = mbedtls_cipher_setup( &cipher_ctx, cipher_info ) ) != 0 )
200 goto exit;
201
202 if( ( ret = mbedtls_cipher_setkey( &cipher_ctx, key, 8 * keylen,
203 (mbedtls_operation_t) mode ) ) != 0 )
204 goto exit;
205
206 if( ( ret = mbedtls_cipher_crypt( &cipher_ctx, iv, enc_scheme_params.len,
207 data, datalen, output, &olen ) ) != 0 )
208 ret = MBEDTLS_ERR_PKCS5_PASSWORD_MISMATCH;
209
210 exit:
211 mbedtls_md_free( &md_ctx );
212 mbedtls_cipher_free( &cipher_ctx );
213
214 return( ret );
215 }
216 #endif /* MBEDTLS_ASN1_PARSE_C */
217
mbedtls_pkcs5_pbkdf2_hmac(mbedtls_md_context_t * ctx,const unsigned char * password,size_t plen,const unsigned char * salt,size_t slen,unsigned int iteration_count,uint32_t key_length,unsigned char * output)218 int mbedtls_pkcs5_pbkdf2_hmac( mbedtls_md_context_t *ctx,
219 const unsigned char *password,
220 size_t plen, const unsigned char *salt, size_t slen,
221 unsigned int iteration_count,
222 uint32_t key_length, unsigned char *output )
223 {
224 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
225 int j;
226 unsigned int i;
227 unsigned char md1[MBEDTLS_MD_MAX_SIZE];
228 unsigned char work[MBEDTLS_MD_MAX_SIZE];
229 unsigned char md_size = mbedtls_md_get_size( ctx->md_info );
230 size_t use_len;
231 unsigned char *out_p = output;
232 unsigned char counter[4];
233
234 memset( counter, 0, 4 );
235 counter[3] = 1;
236
237 #if UINT_MAX > 0xFFFFFFFF
238 if( iteration_count > 0xFFFFFFFF )
239 return( MBEDTLS_ERR_PKCS5_BAD_INPUT_DATA );
240 #endif
241
242 if( ( ret = mbedtls_md_hmac_starts( ctx, password, plen ) ) != 0 )
243 return( ret );
244 while( key_length )
245 {
246 // U1 ends up in work
247 //
248 if( ( ret = mbedtls_md_hmac_update( ctx, salt, slen ) ) != 0 )
249 goto cleanup;
250
251 if( ( ret = mbedtls_md_hmac_update( ctx, counter, 4 ) ) != 0 )
252 goto cleanup;
253
254 if( ( ret = mbedtls_md_hmac_finish( ctx, work ) ) != 0 )
255 goto cleanup;
256
257 if( ( ret = mbedtls_md_hmac_reset( ctx ) ) != 0 )
258 goto cleanup;
259
260 memcpy( md1, work, md_size );
261
262 for( i = 1; i < iteration_count; i++ )
263 {
264 // U2 ends up in md1
265 //
266 if( ( ret = mbedtls_md_hmac_update( ctx, md1, md_size ) ) != 0 )
267 goto cleanup;
268
269 if( ( ret = mbedtls_md_hmac_finish( ctx, md1 ) ) != 0 )
270 goto cleanup;
271
272 if( ( ret = mbedtls_md_hmac_reset( ctx ) ) != 0 )
273 goto cleanup;
274
275 // U1 xor U2
276 //
277 for( j = 0; j < md_size; j++ )
278 work[j] ^= md1[j];
279 }
280
281 use_len = ( key_length < md_size ) ? key_length : md_size;
282 memcpy( out_p, work, use_len );
283
284 key_length -= (uint32_t) use_len;
285 out_p += use_len;
286
287 for( i = 4; i > 0; i-- )
288 if( ++counter[i - 1] != 0 )
289 break;
290 }
291
292 cleanup:
293 /* Zeroise buffers to clear sensitive data from memory. */
294 mbedtls_platform_zeroize( work, MBEDTLS_MD_MAX_SIZE );
295 mbedtls_platform_zeroize( md1, MBEDTLS_MD_MAX_SIZE );
296
297 return( ret );
298 }
299
300 #if defined(MBEDTLS_SELF_TEST)
301
302 #if !defined(MBEDTLS_SHA1_C)
mbedtls_pkcs5_self_test(int verbose)303 int mbedtls_pkcs5_self_test( int verbose )
304 {
305 if( verbose != 0 )
306 mbedtls_printf( " PBKDF2 (SHA1): skipped\n\n" );
307
308 return( 0 );
309 }
310 #else
311
312 #define MAX_TESTS 6
313
314 static const size_t plen_test_data[MAX_TESTS] =
315 { 8, 8, 8, 24, 9 };
316
317 static const unsigned char password_test_data[MAX_TESTS][32] =
318 {
319 "password",
320 "password",
321 "password",
322 "passwordPASSWORDpassword",
323 "pass\0word",
324 };
325
326 static const size_t slen_test_data[MAX_TESTS] =
327 { 4, 4, 4, 36, 5 };
328
329 static const unsigned char salt_test_data[MAX_TESTS][40] =
330 {
331 "salt",
332 "salt",
333 "salt",
334 "saltSALTsaltSALTsaltSALTsaltSALTsalt",
335 "sa\0lt",
336 };
337
338 static const uint32_t it_cnt_test_data[MAX_TESTS] =
339 { 1, 2, 4096, 4096, 4096 };
340
341 static const uint32_t key_len_test_data[MAX_TESTS] =
342 { 20, 20, 20, 25, 16 };
343
344 static const unsigned char result_key_test_data[MAX_TESTS][32] =
345 {
346 { 0x0c, 0x60, 0xc8, 0x0f, 0x96, 0x1f, 0x0e, 0x71,
347 0xf3, 0xa9, 0xb5, 0x24, 0xaf, 0x60, 0x12, 0x06,
348 0x2f, 0xe0, 0x37, 0xa6 },
349 { 0xea, 0x6c, 0x01, 0x4d, 0xc7, 0x2d, 0x6f, 0x8c,
350 0xcd, 0x1e, 0xd9, 0x2a, 0xce, 0x1d, 0x41, 0xf0,
351 0xd8, 0xde, 0x89, 0x57 },
352 { 0x4b, 0x00, 0x79, 0x01, 0xb7, 0x65, 0x48, 0x9a,
353 0xbe, 0xad, 0x49, 0xd9, 0x26, 0xf7, 0x21, 0xd0,
354 0x65, 0xa4, 0x29, 0xc1 },
355 { 0x3d, 0x2e, 0xec, 0x4f, 0xe4, 0x1c, 0x84, 0x9b,
356 0x80, 0xc8, 0xd8, 0x36, 0x62, 0xc0, 0xe4, 0x4a,
357 0x8b, 0x29, 0x1a, 0x96, 0x4c, 0xf2, 0xf0, 0x70,
358 0x38 },
359 { 0x56, 0xfa, 0x6a, 0xa7, 0x55, 0x48, 0x09, 0x9d,
360 0xcc, 0x37, 0xd7, 0xf0, 0x34, 0x25, 0xe0, 0xc3 },
361 };
362
mbedtls_pkcs5_self_test(int verbose)363 int mbedtls_pkcs5_self_test( int verbose )
364 {
365 mbedtls_md_context_t sha1_ctx;
366 const mbedtls_md_info_t *info_sha1;
367 int ret, i;
368 unsigned char key[64];
369
370 mbedtls_md_init( &sha1_ctx );
371
372 info_sha1 = mbedtls_md_info_from_type( MBEDTLS_MD_SHA1 );
373 if( info_sha1 == NULL )
374 {
375 ret = 1;
376 goto exit;
377 }
378
379 if( ( ret = mbedtls_md_setup( &sha1_ctx, info_sha1, 1 ) ) != 0 )
380 {
381 ret = 1;
382 goto exit;
383 }
384
385 for( i = 0; i < MAX_TESTS; i++ )
386 {
387 if( verbose != 0 )
388 mbedtls_printf( " PBKDF2 (SHA1) #%d: ", i );
389
390 ret = mbedtls_pkcs5_pbkdf2_hmac( &sha1_ctx, password_test_data[i],
391 plen_test_data[i], salt_test_data[i],
392 slen_test_data[i], it_cnt_test_data[i],
393 key_len_test_data[i], key );
394 if( ret != 0 ||
395 memcmp( result_key_test_data[i], key, key_len_test_data[i] ) != 0 )
396 {
397 if( verbose != 0 )
398 mbedtls_printf( "failed\n" );
399
400 ret = 1;
401 goto exit;
402 }
403
404 if( verbose != 0 )
405 mbedtls_printf( "passed\n" );
406 }
407
408 if( verbose != 0 )
409 mbedtls_printf( "\n" );
410
411 exit:
412 mbedtls_md_free( &sha1_ctx );
413
414 return( ret );
415 }
416 #endif /* MBEDTLS_SHA1_C */
417
418 #endif /* MBEDTLS_SELF_TEST */
419
420 #endif /* MBEDTLS_PKCS5_C */
421