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 OR GPL-2.0-or-later 10 * 11 * This file is provided under the Apache License 2.0, or the 12 * GNU General Public License v2.0 or later. 13 * 14 * ********** 15 * Apache License 2.0: 16 * 17 * Licensed under the Apache License, Version 2.0 (the "License"); you may 18 * not use this file except in compliance with the License. 19 * You may obtain a copy of the License at 20 * 21 * http://www.apache.org/licenses/LICENSE-2.0 22 * 23 * Unless required by applicable law or agreed to in writing, software 24 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 25 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 26 * See the License for the specific language governing permissions and 27 * limitations under the License. 28 * 29 * ********** 30 * 31 * ********** 32 * GNU General Public License v2.0 or later: 33 * 34 * This program is free software; you can redistribute it and/or modify 35 * it under the terms of the GNU General Public License as published by 36 * the Free Software Foundation; either version 2 of the License, or 37 * (at your option) any later version. 38 * 39 * This program is distributed in the hope that it will be useful, 40 * but WITHOUT ANY WARRANTY; without even the implied warranty of 41 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 42 * GNU General Public License for more details. 43 * 44 * You should have received a copy of the GNU General Public License along 45 * with this program; if not, write to the Free Software Foundation, Inc., 46 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. 47 * 48 * ********** 49 */ 50 /* 51 * PKCS#5 includes PBKDF2 and more 52 * 53 * http://tools.ietf.org/html/rfc2898 (Specification) 54 * http://tools.ietf.org/html/rfc6070 (Test vectors) 55 */ 56 57 #if !defined(MBEDTLS_CONFIG_FILE) 58 #include "mbedtls/config.h" 59 #else 60 #include MBEDTLS_CONFIG_FILE 61 #endif 62 63 #if defined(MBEDTLS_PKCS5_C) 64 65 #include "mbedtls/pkcs5.h" 66 67 #if defined(MBEDTLS_ASN1_PARSE_C) 68 #include "mbedtls/asn1.h" 69 #include "mbedtls/cipher.h" 70 #include "mbedtls/oid.h" 71 #endif /* MBEDTLS_ASN1_PARSE_C */ 72 73 #include <string.h> 74 75 #if defined(MBEDTLS_PLATFORM_C) 76 #include "mbedtls/platform.h" 77 #else 78 #include <stdio.h> 79 #define mbedtls_printf printf 80 #endif 81 82 #if defined(MBEDTLS_ASN1_PARSE_C) 83 static int pkcs5_parse_pbkdf2_params( const mbedtls_asn1_buf *params, 84 mbedtls_asn1_buf *salt, int *iterations, 85 int *keylen, mbedtls_md_type_t *md_type ) 86 { 87 int ret; 88 mbedtls_asn1_buf prf_alg_oid; 89 unsigned char *p = params->p; 90 const unsigned char *end = params->p + params->len; 91 92 if( params->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) 93 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + 94 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ); 95 /* 96 * PBKDF2-params ::= SEQUENCE { 97 * salt OCTET STRING, 98 * iterationCount INTEGER, 99 * keyLength INTEGER OPTIONAL 100 * prf AlgorithmIdentifier DEFAULT algid-hmacWithSHA1 101 * } 102 * 103 */ 104 if( ( ret = mbedtls_asn1_get_tag( &p, end, &salt->len, MBEDTLS_ASN1_OCTET_STRING ) ) != 0 ) 105 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + ret ); 106 107 salt->p = p; 108 p += salt->len; 109 110 if( ( ret = mbedtls_asn1_get_int( &p, end, iterations ) ) != 0 ) 111 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + ret ); 112 113 if( p == end ) 114 return( 0 ); 115 116 if( ( ret = mbedtls_asn1_get_int( &p, end, keylen ) ) != 0 ) 117 { 118 if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) 119 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + ret ); 120 } 121 122 if( p == end ) 123 return( 0 ); 124 125 if( ( ret = mbedtls_asn1_get_alg_null( &p, end, &prf_alg_oid ) ) != 0 ) 126 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + ret ); 127 128 if( mbedtls_oid_get_md_hmac( &prf_alg_oid, md_type ) != 0 ) 129 return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE ); 130 131 if( p != end ) 132 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + 133 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ); 134 135 return( 0 ); 136 } 137 138 int mbedtls_pkcs5_pbes2( const mbedtls_asn1_buf *pbe_params, int mode, 139 const unsigned char *pwd, size_t pwdlen, 140 const unsigned char *data, size_t datalen, 141 unsigned char *output ) 142 { 143 int ret, iterations = 0, keylen = 0; 144 unsigned char *p, *end; 145 mbedtls_asn1_buf kdf_alg_oid, enc_scheme_oid, kdf_alg_params, enc_scheme_params; 146 mbedtls_asn1_buf salt; 147 mbedtls_md_type_t md_type = MBEDTLS_MD_SHA1; 148 unsigned char key[32], iv[32]; 149 size_t olen = 0; 150 const mbedtls_md_info_t *md_info; 151 const mbedtls_cipher_info_t *cipher_info; 152 mbedtls_md_context_t md_ctx; 153 mbedtls_cipher_type_t cipher_alg; 154 mbedtls_cipher_context_t cipher_ctx; 155 156 p = pbe_params->p; 157 end = p + pbe_params->len; 158 159 /* 160 * PBES2-params ::= SEQUENCE { 161 * keyDerivationFunc AlgorithmIdentifier {{PBES2-KDFs}}, 162 * encryptionScheme AlgorithmIdentifier {{PBES2-Encs}} 163 * } 164 */ 165 if( pbe_params->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) 166 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + 167 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ); 168 169 if( ( ret = mbedtls_asn1_get_alg( &p, end, &kdf_alg_oid, &kdf_alg_params ) ) != 0 ) 170 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + ret ); 171 172 // Only PBKDF2 supported at the moment 173 // 174 if( MBEDTLS_OID_CMP( MBEDTLS_OID_PKCS5_PBKDF2, &kdf_alg_oid ) != 0 ) 175 return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE ); 176 177 if( ( ret = pkcs5_parse_pbkdf2_params( &kdf_alg_params, 178 &salt, &iterations, &keylen, 179 &md_type ) ) != 0 ) 180 { 181 return( ret ); 182 } 183 184 md_info = mbedtls_md_info_from_type( md_type ); 185 if( md_info == NULL ) 186 return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE ); 187 188 if( ( ret = mbedtls_asn1_get_alg( &p, end, &enc_scheme_oid, 189 &enc_scheme_params ) ) != 0 ) 190 { 191 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + ret ); 192 } 193 194 if( mbedtls_oid_get_cipher_alg( &enc_scheme_oid, &cipher_alg ) != 0 ) 195 return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE ); 196 197 cipher_info = mbedtls_cipher_info_from_type( cipher_alg ); 198 if( cipher_info == NULL ) 199 return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE ); 200 201 /* 202 * The value of keylen from pkcs5_parse_pbkdf2_params() is ignored 203 * since it is optional and we don't know if it was set or not 204 */ 205 keylen = cipher_info->key_bitlen / 8; 206 207 if( enc_scheme_params.tag != MBEDTLS_ASN1_OCTET_STRING || 208 enc_scheme_params.len != cipher_info->iv_size ) 209 { 210 return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT ); 211 } 212 213 mbedtls_md_init( &md_ctx ); 214 mbedtls_cipher_init( &cipher_ctx ); 215 216 memcpy( iv, enc_scheme_params.p, enc_scheme_params.len ); 217 218 if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 1 ) ) != 0 ) 219 goto exit; 220 221 if( ( ret = mbedtls_pkcs5_pbkdf2_hmac( &md_ctx, pwd, pwdlen, salt.p, salt.len, 222 iterations, keylen, key ) ) != 0 ) 223 { 224 goto exit; 225 } 226 227 if( ( ret = mbedtls_cipher_setup( &cipher_ctx, cipher_info ) ) != 0 ) 228 goto exit; 229 230 if( ( ret = mbedtls_cipher_setkey( &cipher_ctx, key, 8 * keylen, (mbedtls_operation_t) mode ) ) != 0 ) 231 goto exit; 232 233 if( ( ret = mbedtls_cipher_crypt( &cipher_ctx, iv, enc_scheme_params.len, 234 data, datalen, output, &olen ) ) != 0 ) 235 ret = MBEDTLS_ERR_PKCS5_PASSWORD_MISMATCH; 236 237 exit: 238 mbedtls_md_free( &md_ctx ); 239 mbedtls_cipher_free( &cipher_ctx ); 240 241 return( ret ); 242 } 243 #endif /* MBEDTLS_ASN1_PARSE_C */ 244 245 int mbedtls_pkcs5_pbkdf2_hmac( mbedtls_md_context_t *ctx, const unsigned char *password, 246 size_t plen, const unsigned char *salt, size_t slen, 247 unsigned int iteration_count, 248 uint32_t key_length, unsigned char *output ) 249 { 250 int ret = 0, j; 251 unsigned int i; 252 unsigned char md1[MBEDTLS_MD_MAX_SIZE]; 253 unsigned char work[MBEDTLS_MD_MAX_SIZE]; 254 unsigned char md_size = mbedtls_md_get_size( ctx->md_info ); 255 size_t use_len; 256 unsigned char *out_p = output; 257 unsigned char counter[4]; 258 259 memset( counter, 0, 4 ); 260 counter[3] = 1; 261 262 #if UINT_MAX > 0xFFFFFFFF 263 if( iteration_count > 0xFFFFFFFF ) 264 return( MBEDTLS_ERR_PKCS5_BAD_INPUT_DATA ); 265 #endif 266 267 while( key_length ) 268 { 269 // U1 ends up in work 270 // 271 if( ( ret = mbedtls_md_hmac_starts( ctx, password, plen ) ) != 0 ) 272 goto cleanup; 273 274 if( ( ret = mbedtls_md_hmac_update( ctx, salt, slen ) ) != 0 ) 275 goto cleanup; 276 277 if( ( ret = mbedtls_md_hmac_update( ctx, counter, 4 ) ) != 0 ) 278 goto cleanup; 279 280 if( ( ret = mbedtls_md_hmac_finish( ctx, work ) ) != 0 ) 281 goto cleanup; 282 283 memcpy( md1, work, md_size ); 284 285 for( i = 1; i < iteration_count; i++ ) 286 { 287 // U2 ends up in md1 288 // 289 if( ( ret = mbedtls_md_hmac_starts( ctx, password, plen ) ) != 0 ) 290 goto cleanup; 291 292 if( ( ret = mbedtls_md_hmac_update( ctx, md1, md_size ) ) != 0 ) 293 goto cleanup; 294 295 if( ( ret = mbedtls_md_hmac_finish( ctx, md1 ) ) != 0 ) 296 goto cleanup; 297 298 // U1 xor U2 299 // 300 for( j = 0; j < md_size; j++ ) 301 work[j] ^= md1[j]; 302 } 303 304 use_len = ( key_length < md_size ) ? key_length : md_size; 305 memcpy( out_p, work, use_len ); 306 307 key_length -= (uint32_t) use_len; 308 out_p += use_len; 309 310 for( i = 4; i > 0; i-- ) 311 if( ++counter[i - 1] != 0 ) 312 break; 313 } 314 315 cleanup: 316 /* Zeroise buffers to clear sensitive data from memory. */ 317 mbedtls_platform_zeroize( work, MBEDTLS_MD_MAX_SIZE ); 318 mbedtls_platform_zeroize( md1, MBEDTLS_MD_MAX_SIZE ); 319 320 return( ret ); 321 } 322 323 #if defined(MBEDTLS_SELF_TEST) 324 325 #if !defined(MBEDTLS_SHA1_C) 326 int mbedtls_pkcs5_self_test( int verbose ) 327 { 328 if( verbose != 0 ) 329 mbedtls_printf( " PBKDF2 (SHA1): skipped\n\n" ); 330 331 return( 0 ); 332 } 333 #else 334 335 #define MAX_TESTS 6 336 337 static const size_t plen[MAX_TESTS] = 338 { 8, 8, 8, 24, 9 }; 339 340 static const unsigned char password[MAX_TESTS][32] = 341 { 342 "password", 343 "password", 344 "password", 345 "passwordPASSWORDpassword", 346 "pass\0word", 347 }; 348 349 static const size_t slen[MAX_TESTS] = 350 { 4, 4, 4, 36, 5 }; 351 352 static const unsigned char salt[MAX_TESTS][40] = 353 { 354 "salt", 355 "salt", 356 "salt", 357 "saltSALTsaltSALTsaltSALTsaltSALTsalt", 358 "sa\0lt", 359 }; 360 361 static const uint32_t it_cnt[MAX_TESTS] = 362 { 1, 2, 4096, 4096, 4096 }; 363 364 static const uint32_t key_len[MAX_TESTS] = 365 { 20, 20, 20, 25, 16 }; 366 367 static const unsigned char result_key[MAX_TESTS][32] = 368 { 369 { 0x0c, 0x60, 0xc8, 0x0f, 0x96, 0x1f, 0x0e, 0x71, 370 0xf3, 0xa9, 0xb5, 0x24, 0xaf, 0x60, 0x12, 0x06, 371 0x2f, 0xe0, 0x37, 0xa6 }, 372 { 0xea, 0x6c, 0x01, 0x4d, 0xc7, 0x2d, 0x6f, 0x8c, 373 0xcd, 0x1e, 0xd9, 0x2a, 0xce, 0x1d, 0x41, 0xf0, 374 0xd8, 0xde, 0x89, 0x57 }, 375 { 0x4b, 0x00, 0x79, 0x01, 0xb7, 0x65, 0x48, 0x9a, 376 0xbe, 0xad, 0x49, 0xd9, 0x26, 0xf7, 0x21, 0xd0, 377 0x65, 0xa4, 0x29, 0xc1 }, 378 { 0x3d, 0x2e, 0xec, 0x4f, 0xe4, 0x1c, 0x84, 0x9b, 379 0x80, 0xc8, 0xd8, 0x36, 0x62, 0xc0, 0xe4, 0x4a, 380 0x8b, 0x29, 0x1a, 0x96, 0x4c, 0xf2, 0xf0, 0x70, 381 0x38 }, 382 { 0x56, 0xfa, 0x6a, 0xa7, 0x55, 0x48, 0x09, 0x9d, 383 0xcc, 0x37, 0xd7, 0xf0, 0x34, 0x25, 0xe0, 0xc3 }, 384 }; 385 386 int mbedtls_pkcs5_self_test( int verbose ) 387 { 388 mbedtls_md_context_t sha1_ctx; 389 const mbedtls_md_info_t *info_sha1; 390 int ret, i; 391 unsigned char key[64]; 392 393 mbedtls_md_init( &sha1_ctx ); 394 395 info_sha1 = mbedtls_md_info_from_type( MBEDTLS_MD_SHA1 ); 396 if( info_sha1 == NULL ) 397 { 398 ret = 1; 399 goto exit; 400 } 401 402 if( ( ret = mbedtls_md_setup( &sha1_ctx, info_sha1, 1 ) ) != 0 ) 403 { 404 ret = 1; 405 goto exit; 406 } 407 408 for( i = 0; i < MAX_TESTS; i++ ) 409 { 410 if( verbose != 0 ) 411 mbedtls_printf( " PBKDF2 (SHA1) #%d: ", i ); 412 413 ret = mbedtls_pkcs5_pbkdf2_hmac( &sha1_ctx, password[i], plen[i], salt[i], 414 slen[i], it_cnt[i], key_len[i], key ); 415 if( ret != 0 || 416 memcmp( result_key[i], key, key_len[i] ) != 0 ) 417 { 418 if( verbose != 0 ) 419 mbedtls_printf( "failed\n" ); 420 421 ret = 1; 422 goto exit; 423 } 424 425 if( verbose != 0 ) 426 mbedtls_printf( "passed\n" ); 427 } 428 429 if( verbose != 0 ) 430 mbedtls_printf( "\n" ); 431 432 exit: 433 mbedtls_md_free( &sha1_ctx ); 434 435 return( ret ); 436 } 437 #endif /* MBEDTLS_SHA1_C */ 438 439 #endif /* MBEDTLS_SELF_TEST */ 440 441 #endif /* MBEDTLS_PKCS5_C */ 442