1 // SPDX-License-Identifier: Apache-2.0 2 /** 3 * \file pkcs5.c 4 * 5 * \brief PKCS#5 functions 6 * 7 * \author Mathias Olsson <mathias@kompetensum.com> 8 * 9 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved 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 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 } 110 111 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 } 216 217 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) 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 }; 350 351 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