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) 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 } 108 109 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 */ 217 218 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) 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 }; 362 363 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