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