1 /**
2 * \file pkcs5.c
3 *
4 * \brief PKCS#5 functions
5 *
6 * \author Mathias Olsson <mathias@kompetensum.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 * PKCS#5 includes PBKDF2 and more
27 *
28 * http://tools.ietf.org/html/rfc2898 (Specification)
29 * http://tools.ietf.org/html/rfc6070 (Test vectors)
30 */
31
32 #if !defined(MBEDTLS_CONFIG_FILE)
33 #include "mbedtls/config.h"
34 #else
35 #include MBEDTLS_CONFIG_FILE
36 #endif
37
38 #if defined(MBEDTLS_PKCS5_C)
39
40 #include "mbedtls/pkcs5.h"
41 #include "mbedtls/asn1.h"
42 #include "mbedtls/cipher.h"
43 #include "mbedtls/oid.h"
44
45 #include <string.h>
46
47 #if defined(MBEDTLS_PLATFORM_C)
48 #include "mbedtls/platform.h"
49 #else
50 #include <stdio.h>
51 #define mbedtls_printf printf
52 #endif
53
pkcs5_parse_pbkdf2_params(const mbedtls_asn1_buf * params,mbedtls_asn1_buf * salt,int * iterations,int * keylen,mbedtls_md_type_t * md_type)54 static int pkcs5_parse_pbkdf2_params( const mbedtls_asn1_buf *params,
55 mbedtls_asn1_buf *salt, int *iterations,
56 int *keylen, mbedtls_md_type_t *md_type )
57 {
58 int ret;
59 mbedtls_asn1_buf prf_alg_oid;
60 unsigned char *p = params->p;
61 const unsigned char *end = params->p + params->len;
62
63 if( params->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) )
64 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT +
65 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
66 /*
67 * PBKDF2-params ::= SEQUENCE {
68 * salt OCTET STRING,
69 * iterationCount INTEGER,
70 * keyLength INTEGER OPTIONAL
71 * prf AlgorithmIdentifier DEFAULT algid-hmacWithSHA1
72 * }
73 *
74 */
75 if( ( ret = mbedtls_asn1_get_tag( &p, end, &salt->len, MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
76 return( 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_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_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_ERR_PKCS5_INVALID_FORMAT + ret );
98
99 if( MBEDTLS_OID_CMP( MBEDTLS_OID_HMAC_SHA1, &prf_alg_oid ) != 0 )
100 return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );
101
102 *md_type = MBEDTLS_MD_SHA1;
103
104 if( p != end )
105 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT +
106 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
107
108 return( 0 );
109 }
110
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)111 int mbedtls_pkcs5_pbes2( const mbedtls_asn1_buf *pbe_params, int mode,
112 const unsigned char *pwd, size_t pwdlen,
113 const unsigned char *data, size_t datalen,
114 unsigned char *output )
115 {
116 int ret, iterations = 0, keylen = 0;
117 unsigned char *p, *end;
118 mbedtls_asn1_buf kdf_alg_oid, enc_scheme_oid, kdf_alg_params, enc_scheme_params;
119 mbedtls_asn1_buf salt;
120 mbedtls_md_type_t md_type = MBEDTLS_MD_SHA1;
121 unsigned char key[32], iv[32];
122 size_t olen = 0;
123 const mbedtls_md_info_t *md_info;
124 const mbedtls_cipher_info_t *cipher_info;
125 mbedtls_md_context_t md_ctx;
126 mbedtls_cipher_type_t cipher_alg;
127 mbedtls_cipher_context_t cipher_ctx;
128
129 p = pbe_params->p;
130 end = p + pbe_params->len;
131
132 /*
133 * PBES2-params ::= SEQUENCE {
134 * keyDerivationFunc AlgorithmIdentifier {{PBES2-KDFs}},
135 * encryptionScheme AlgorithmIdentifier {{PBES2-Encs}}
136 * }
137 */
138 if( pbe_params->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) )
139 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT +
140 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
141
142 if( ( ret = mbedtls_asn1_get_alg( &p, end, &kdf_alg_oid, &kdf_alg_params ) ) != 0 )
143 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + ret );
144
145 // Only PBKDF2 supported at the moment
146 //
147 if( MBEDTLS_OID_CMP( MBEDTLS_OID_PKCS5_PBKDF2, &kdf_alg_oid ) != 0 )
148 return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );
149
150 if( ( ret = pkcs5_parse_pbkdf2_params( &kdf_alg_params,
151 &salt, &iterations, &keylen,
152 &md_type ) ) != 0 )
153 {
154 return( ret );
155 }
156
157 md_info = mbedtls_md_info_from_type( md_type );
158 if( md_info == NULL )
159 return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );
160
161 if( ( ret = mbedtls_asn1_get_alg( &p, end, &enc_scheme_oid,
162 &enc_scheme_params ) ) != 0 )
163 {
164 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + ret );
165 }
166
167 if( mbedtls_oid_get_cipher_alg( &enc_scheme_oid, &cipher_alg ) != 0 )
168 return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );
169
170 cipher_info = mbedtls_cipher_info_from_type( cipher_alg );
171 if( cipher_info == NULL )
172 return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );
173
174 /*
175 * The value of keylen from pkcs5_parse_pbkdf2_params() is ignored
176 * since it is optional and we don't know if it was set or not
177 */
178 keylen = cipher_info->key_bitlen / 8;
179
180 if( enc_scheme_params.tag != MBEDTLS_ASN1_OCTET_STRING ||
181 enc_scheme_params.len != cipher_info->iv_size )
182 {
183 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT );
184 }
185
186 mbedtls_md_init( &md_ctx );
187 mbedtls_cipher_init( &cipher_ctx );
188
189 memcpy( iv, enc_scheme_params.p, enc_scheme_params.len );
190
191 if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 1 ) ) != 0 )
192 goto exit;
193
194 if( ( ret = mbedtls_pkcs5_pbkdf2_hmac( &md_ctx, pwd, pwdlen, salt.p, salt.len,
195 iterations, keylen, key ) ) != 0 )
196 {
197 goto exit;
198 }
199
200 if( ( ret = mbedtls_cipher_setup( &cipher_ctx, cipher_info ) ) != 0 )
201 goto exit;
202
203 if( ( ret = mbedtls_cipher_setkey( &cipher_ctx, key, 8 * keylen, (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
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)217 int mbedtls_pkcs5_pbkdf2_hmac( mbedtls_md_context_t *ctx, const unsigned char *password,
218 size_t plen, const unsigned char *salt, size_t slen,
219 unsigned int iteration_count,
220 uint32_t key_length, unsigned char *output )
221 {
222 int ret, j;
223 unsigned int i;
224 unsigned char md1[MBEDTLS_MD_MAX_SIZE];
225 unsigned char work[MBEDTLS_MD_MAX_SIZE];
226 unsigned char md_size = mbedtls_md_get_size( ctx->md_info );
227 size_t use_len;
228 unsigned char *out_p = output;
229 unsigned char counter[4];
230
231 memset( counter, 0, 4 );
232 counter[3] = 1;
233
234 if( iteration_count > 0xFFFFFFFF )
235 return( MBEDTLS_ERR_PKCS5_BAD_INPUT_DATA );
236
237 while( key_length )
238 {
239 // U1 ends up in work
240 //
241 if( ( ret = mbedtls_md_hmac_starts( ctx, password, plen ) ) != 0 )
242 return( ret );
243
244 if( ( ret = mbedtls_md_hmac_update( ctx, salt, slen ) ) != 0 )
245 return( ret );
246
247 if( ( ret = mbedtls_md_hmac_update( ctx, counter, 4 ) ) != 0 )
248 return( ret );
249
250 if( ( ret = mbedtls_md_hmac_finish( ctx, work ) ) != 0 )
251 return( ret );
252
253 memcpy( md1, work, md_size );
254
255 for( i = 1; i < iteration_count; i++ )
256 {
257 // U2 ends up in md1
258 //
259 if( ( ret = mbedtls_md_hmac_starts( ctx, password, plen ) ) != 0 )
260 return( ret );
261
262 if( ( ret = mbedtls_md_hmac_update( ctx, md1, md_size ) ) != 0 )
263 return( ret );
264
265 if( ( ret = mbedtls_md_hmac_finish( ctx, md1 ) ) != 0 )
266 return( ret );
267
268 // U1 xor U2
269 //
270 for( j = 0; j < md_size; j++ )
271 work[j] ^= md1[j];
272 }
273
274 use_len = ( key_length < md_size ) ? key_length : md_size;
275 memcpy( out_p, work, use_len );
276
277 key_length -= (uint32_t) use_len;
278 out_p += use_len;
279
280 for( i = 4; i > 0; i-- )
281 if( ++counter[i - 1] != 0 )
282 break;
283 }
284
285 return( 0 );
286 }
287
288 #if defined(MBEDTLS_SELF_TEST)
289
290 #if !defined(MBEDTLS_SHA1_C)
mbedtls_pkcs5_self_test(int verbose)291 int mbedtls_pkcs5_self_test( int verbose )
292 {
293 if( verbose != 0 )
294 mbedtls_printf( " PBKDF2 (SHA1): skipped\n\n" );
295
296 return( 0 );
297 }
298 #else
299
300 #define MAX_TESTS 6
301
302 static const size_t plen[MAX_TESTS] =
303 { 8, 8, 8, 24, 9 };
304
305 static const unsigned char password[MAX_TESTS][32] =
306 {
307 "password",
308 "password",
309 "password",
310 "passwordPASSWORDpassword",
311 "pass\0word",
312 };
313
314 static const size_t slen[MAX_TESTS] =
315 { 4, 4, 4, 36, 5 };
316
317 static const unsigned char salt[MAX_TESTS][40] =
318 {
319 "salt",
320 "salt",
321 "salt",
322 "saltSALTsaltSALTsaltSALTsaltSALTsalt",
323 "sa\0lt",
324 };
325
326 static const uint32_t it_cnt[MAX_TESTS] =
327 { 1, 2, 4096, 4096, 4096 };
328
329 static const uint32_t key_len[MAX_TESTS] =
330 { 20, 20, 20, 25, 16 };
331
332 static const unsigned char result_key[MAX_TESTS][32] =
333 {
334 { 0x0c, 0x60, 0xc8, 0x0f, 0x96, 0x1f, 0x0e, 0x71,
335 0xf3, 0xa9, 0xb5, 0x24, 0xaf, 0x60, 0x12, 0x06,
336 0x2f, 0xe0, 0x37, 0xa6 },
337 { 0xea, 0x6c, 0x01, 0x4d, 0xc7, 0x2d, 0x6f, 0x8c,
338 0xcd, 0x1e, 0xd9, 0x2a, 0xce, 0x1d, 0x41, 0xf0,
339 0xd8, 0xde, 0x89, 0x57 },
340 { 0x4b, 0x00, 0x79, 0x01, 0xb7, 0x65, 0x48, 0x9a,
341 0xbe, 0xad, 0x49, 0xd9, 0x26, 0xf7, 0x21, 0xd0,
342 0x65, 0xa4, 0x29, 0xc1 },
343 { 0x3d, 0x2e, 0xec, 0x4f, 0xe4, 0x1c, 0x84, 0x9b,
344 0x80, 0xc8, 0xd8, 0x36, 0x62, 0xc0, 0xe4, 0x4a,
345 0x8b, 0x29, 0x1a, 0x96, 0x4c, 0xf2, 0xf0, 0x70,
346 0x38 },
347 { 0x56, 0xfa, 0x6a, 0xa7, 0x55, 0x48, 0x09, 0x9d,
348 0xcc, 0x37, 0xd7, 0xf0, 0x34, 0x25, 0xe0, 0xc3 },
349 };
350
mbedtls_pkcs5_self_test(int verbose)351 int mbedtls_pkcs5_self_test( int verbose )
352 {
353 mbedtls_md_context_t sha1_ctx;
354 const mbedtls_md_info_t *info_sha1;
355 int ret, i;
356 unsigned char key[64];
357
358 mbedtls_md_init( &sha1_ctx );
359
360 info_sha1 = mbedtls_md_info_from_type( MBEDTLS_MD_SHA1 );
361 if( info_sha1 == NULL )
362 {
363 ret = 1;
364 goto exit;
365 }
366
367 if( ( ret = mbedtls_md_setup( &sha1_ctx, info_sha1, 1 ) ) != 0 )
368 {
369 ret = 1;
370 goto exit;
371 }
372
373 for( i = 0; i < MAX_TESTS; i++ )
374 {
375 if( verbose != 0 )
376 mbedtls_printf( " PBKDF2 (SHA1) #%d: ", i );
377
378 ret = mbedtls_pkcs5_pbkdf2_hmac( &sha1_ctx, password[i], plen[i], salt[i],
379 slen[i], it_cnt[i], key_len[i], key );
380 if( ret != 0 ||
381 memcmp( result_key[i], key, key_len[i] ) != 0 )
382 {
383 if( verbose != 0 )
384 mbedtls_printf( "failed\n" );
385
386 ret = 1;
387 goto exit;
388 }
389
390 if( verbose != 0 )
391 mbedtls_printf( "passed\n" );
392 }
393
394 if( verbose != 0 )
395 mbedtls_printf( "\n" );
396
397 exit:
398 mbedtls_md_free( &sha1_ctx );
399
400 return( ret );
401 }
402 #endif /* MBEDTLS_SHA1_C */
403
404 #endif /* MBEDTLS_SELF_TEST */
405
406 #endif /* MBEDTLS_PKCS5_C */
407
