1 /* 2 * Copyright 2006-2021 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the OpenSSL license (the "License"). You may not use 5 * this file except in compliance with the License. You can obtain a copy 6 * in the file LICENSE in the source distribution or at 7 * https://www.openssl.org/source/license.html 8 */ 9 10 #include <stdio.h> 11 #include "internal/cryptlib.h" 12 #include <openssl/objects.h> 13 #include <openssl/ts.h> 14 #include <openssl/pkcs7.h> 15 #include "ts_local.h" 16 17 static int ts_verify_cert(X509_STORE *store, STACK_OF(X509) *untrusted, 18 X509 *signer, STACK_OF(X509) **chain); 19 static int ts_check_signing_certs(PKCS7_SIGNER_INFO *si, 20 STACK_OF(X509) *chain); 21 static ESS_SIGNING_CERT *ess_get_signing_cert(PKCS7_SIGNER_INFO *si); 22 static int ts_find_cert(STACK_OF(ESS_CERT_ID) *cert_ids, X509 *cert); 23 static int ts_issuer_serial_cmp(ESS_ISSUER_SERIAL *is, X509 *cert); 24 static int int_ts_RESP_verify_token(TS_VERIFY_CTX *ctx, 25 PKCS7 *token, TS_TST_INFO *tst_info); 26 static int ts_check_status_info(TS_RESP *response); 27 static char *ts_get_status_text(STACK_OF(ASN1_UTF8STRING) *text); 28 static int ts_check_policy(const ASN1_OBJECT *req_oid, 29 const TS_TST_INFO *tst_info); 30 static int ts_compute_imprint(BIO *data, TS_TST_INFO *tst_info, 31 X509_ALGOR **md_alg, 32 unsigned char **imprint, unsigned *imprint_len); 33 static int ts_check_imprints(X509_ALGOR *algor_a, 34 const unsigned char *imprint_a, unsigned len_a, 35 TS_TST_INFO *tst_info); 36 static int ts_check_nonces(const ASN1_INTEGER *a, TS_TST_INFO *tst_info); 37 static int ts_check_signer_name(GENERAL_NAME *tsa_name, X509 *signer); 38 static int ts_find_name(STACK_OF(GENERAL_NAME) *gen_names, 39 GENERAL_NAME *name); 40 static int ts_find_cert_v2(STACK_OF(ESS_CERT_ID_V2) *cert_ids, X509 *cert); 41 static ESS_SIGNING_CERT_V2 *ess_get_signing_cert_v2(PKCS7_SIGNER_INFO *si); 42 43 /* 44 * This must be large enough to hold all values in ts_status_text (with 45 * comma separator) or all text fields in ts_failure_info (also with comma). 46 */ 47 #define TS_STATUS_BUF_SIZE 256 48 49 /* 50 * Local mapping between response codes and descriptions. 51 */ 52 static const char *ts_status_text[] = { 53 "granted", 54 "grantedWithMods", 55 "rejection", 56 "waiting", 57 "revocationWarning", 58 "revocationNotification" 59 }; 60 61 #define TS_STATUS_TEXT_SIZE OSSL_NELEM(ts_status_text) 62 63 static struct { 64 int code; 65 const char *text; 66 } ts_failure_info[] = { 67 {TS_INFO_BAD_ALG, "badAlg"}, 68 {TS_INFO_BAD_REQUEST, "badRequest"}, 69 {TS_INFO_BAD_DATA_FORMAT, "badDataFormat"}, 70 {TS_INFO_TIME_NOT_AVAILABLE, "timeNotAvailable"}, 71 {TS_INFO_UNACCEPTED_POLICY, "unacceptedPolicy"}, 72 {TS_INFO_UNACCEPTED_EXTENSION, "unacceptedExtension"}, 73 {TS_INFO_ADD_INFO_NOT_AVAILABLE, "addInfoNotAvailable"}, 74 {TS_INFO_SYSTEM_FAILURE, "systemFailure"} 75 }; 76 77 78 /*- 79 * This function carries out the following tasks: 80 * - Checks if there is one and only one signer. 81 * - Search for the signing certificate in 'certs' and in the response. 82 * - Check the extended key usage and key usage fields of the signer 83 * certificate (done by the path validation). 84 * - Build and validate the certificate path. 85 * - Check if the certificate path meets the requirements of the 86 * SigningCertificate ESS signed attribute. 87 * - Verify the signature value. 88 * - Returns the signer certificate in 'signer', if 'signer' is not NULL. 89 */ 90 int TS_RESP_verify_signature(PKCS7 *token, STACK_OF(X509) *certs, 91 X509_STORE *store, X509 **signer_out) 92 { 93 STACK_OF(PKCS7_SIGNER_INFO) *sinfos = NULL; 94 PKCS7_SIGNER_INFO *si; 95 STACK_OF(X509) *signers = NULL; 96 X509 *signer; 97 STACK_OF(X509) *chain = NULL; 98 char buf[4096]; 99 int i, j = 0, ret = 0; 100 BIO *p7bio = NULL; 101 102 /* Some sanity checks first. */ 103 if (!token) { 104 TSerr(TS_F_TS_RESP_VERIFY_SIGNATURE, TS_R_INVALID_NULL_POINTER); 105 goto err; 106 } 107 if (!PKCS7_type_is_signed(token)) { 108 TSerr(TS_F_TS_RESP_VERIFY_SIGNATURE, TS_R_WRONG_CONTENT_TYPE); 109 goto err; 110 } 111 sinfos = PKCS7_get_signer_info(token); 112 if (!sinfos || sk_PKCS7_SIGNER_INFO_num(sinfos) != 1) { 113 TSerr(TS_F_TS_RESP_VERIFY_SIGNATURE, TS_R_THERE_MUST_BE_ONE_SIGNER); 114 goto err; 115 } 116 si = sk_PKCS7_SIGNER_INFO_value(sinfos, 0); 117 if (PKCS7_get_detached(token)) { 118 TSerr(TS_F_TS_RESP_VERIFY_SIGNATURE, TS_R_NO_CONTENT); 119 goto err; 120 } 121 122 /* 123 * Get hold of the signer certificate, search only internal certificates 124 * if it was requested. 125 */ 126 signers = PKCS7_get0_signers(token, certs, 0); 127 if (!signers || sk_X509_num(signers) != 1) 128 goto err; 129 signer = sk_X509_value(signers, 0); 130 131 if (!ts_verify_cert(store, certs, signer, &chain)) 132 goto err; 133 if (!ts_check_signing_certs(si, chain)) 134 goto err; 135 p7bio = PKCS7_dataInit(token, NULL); 136 137 /* We now have to 'read' from p7bio to calculate digests etc. */ 138 while ((i = BIO_read(p7bio, buf, sizeof(buf))) > 0) 139 continue; 140 141 j = PKCS7_signatureVerify(p7bio, token, si, signer); 142 if (j <= 0) { 143 TSerr(TS_F_TS_RESP_VERIFY_SIGNATURE, TS_R_SIGNATURE_FAILURE); 144 goto err; 145 } 146 147 if (signer_out) { 148 *signer_out = signer; 149 X509_up_ref(signer); 150 } 151 ret = 1; 152 153 err: 154 BIO_free_all(p7bio); 155 sk_X509_pop_free(chain, X509_free); 156 sk_X509_free(signers); 157 158 return ret; 159 } 160 161 /* 162 * The certificate chain is returned in chain. Caller is responsible for 163 * freeing the vector. 164 */ 165 static int ts_verify_cert(X509_STORE *store, STACK_OF(X509) *untrusted, 166 X509 *signer, STACK_OF(X509) **chain) 167 { 168 X509_STORE_CTX *cert_ctx = NULL; 169 int i; 170 int ret = 0; 171 172 *chain = NULL; 173 cert_ctx = X509_STORE_CTX_new(); 174 if (cert_ctx == NULL) { 175 TSerr(TS_F_TS_VERIFY_CERT, ERR_R_MALLOC_FAILURE); 176 goto err; 177 } 178 if (!X509_STORE_CTX_init(cert_ctx, store, signer, untrusted)) 179 goto end; 180 X509_STORE_CTX_set_purpose(cert_ctx, X509_PURPOSE_TIMESTAMP_SIGN); 181 i = X509_verify_cert(cert_ctx); 182 if (i <= 0) { 183 int j = X509_STORE_CTX_get_error(cert_ctx); 184 TSerr(TS_F_TS_VERIFY_CERT, TS_R_CERTIFICATE_VERIFY_ERROR); 185 ERR_add_error_data(2, "Verify error:", 186 X509_verify_cert_error_string(j)); 187 goto err; 188 } 189 *chain = X509_STORE_CTX_get1_chain(cert_ctx); 190 ret = 1; 191 goto end; 192 193 err: 194 ret = 0; 195 196 end: 197 X509_STORE_CTX_free(cert_ctx); 198 return ret; 199 } 200 201 static int ts_check_signing_certs(PKCS7_SIGNER_INFO *si, 202 STACK_OF(X509) *chain) 203 { 204 ESS_SIGNING_CERT *ss = ess_get_signing_cert(si); 205 STACK_OF(ESS_CERT_ID) *cert_ids = NULL; 206 ESS_SIGNING_CERT_V2 *ssv2 = ess_get_signing_cert_v2(si); 207 STACK_OF(ESS_CERT_ID_V2) *cert_ids_v2 = NULL; 208 X509 *cert; 209 int i = 0; 210 int ret = 0; 211 212 if (ss != NULL) { 213 cert_ids = ss->cert_ids; 214 cert = sk_X509_value(chain, 0); 215 if (ts_find_cert(cert_ids, cert) != 0) 216 goto err; 217 218 /* 219 * Check the other certificates of the chain if there are more than one 220 * certificate ids in cert_ids. 221 */ 222 if (sk_ESS_CERT_ID_num(cert_ids) > 1) { 223 for (i = 1; i < sk_X509_num(chain); ++i) { 224 cert = sk_X509_value(chain, i); 225 if (ts_find_cert(cert_ids, cert) < 0) 226 goto err; 227 } 228 } 229 } else if (ssv2 != NULL) { 230 cert_ids_v2 = ssv2->cert_ids; 231 cert = sk_X509_value(chain, 0); 232 if (ts_find_cert_v2(cert_ids_v2, cert) != 0) 233 goto err; 234 235 /* 236 * Check the other certificates of the chain if there are more than one 237 * certificate ids in cert_ids. 238 */ 239 if (sk_ESS_CERT_ID_V2_num(cert_ids_v2) > 1) { 240 for (i = 1; i < sk_X509_num(chain); ++i) { 241 cert = sk_X509_value(chain, i); 242 if (ts_find_cert_v2(cert_ids_v2, cert) < 0) 243 goto err; 244 } 245 } 246 } else { 247 goto err; 248 } 249 250 ret = 1; 251 err: 252 if (!ret) 253 TSerr(TS_F_TS_CHECK_SIGNING_CERTS, 254 TS_R_ESS_SIGNING_CERTIFICATE_ERROR); 255 ESS_SIGNING_CERT_free(ss); 256 ESS_SIGNING_CERT_V2_free(ssv2); 257 return ret; 258 } 259 260 static ESS_SIGNING_CERT *ess_get_signing_cert(PKCS7_SIGNER_INFO *si) 261 { 262 ASN1_TYPE *attr; 263 const unsigned char *p; 264 attr = PKCS7_get_signed_attribute(si, NID_id_smime_aa_signingCertificate); 265 if (!attr) 266 return NULL; 267 p = attr->value.sequence->data; 268 return d2i_ESS_SIGNING_CERT(NULL, &p, attr->value.sequence->length); 269 } 270 271 static ESS_SIGNING_CERT_V2 *ess_get_signing_cert_v2(PKCS7_SIGNER_INFO *si) 272 { 273 ASN1_TYPE *attr; 274 const unsigned char *p; 275 276 attr = PKCS7_get_signed_attribute(si, NID_id_smime_aa_signingCertificateV2); 277 if (attr == NULL) 278 return NULL; 279 p = attr->value.sequence->data; 280 return d2i_ESS_SIGNING_CERT_V2(NULL, &p, attr->value.sequence->length); 281 } 282 283 /* Returns < 0 if certificate is not found, certificate index otherwise. */ 284 static int ts_find_cert(STACK_OF(ESS_CERT_ID) *cert_ids, X509 *cert) 285 { 286 int i; 287 unsigned char cert_sha1[SHA_DIGEST_LENGTH]; 288 289 if (!cert_ids || !cert) 290 return -1; 291 292 /* Recompute SHA1 hash of certificate if necessary (side effect). */ 293 X509_check_purpose(cert, -1, 0); 294 295 if (!X509_digest(cert, EVP_sha1(), cert_sha1, NULL)) 296 return -1; 297 298 /* Look for cert in the cert_ids vector. */ 299 for (i = 0; i < sk_ESS_CERT_ID_num(cert_ids); ++i) { 300 ESS_CERT_ID *cid = sk_ESS_CERT_ID_value(cert_ids, i); 301 302 if (cid->hash->length == SHA_DIGEST_LENGTH 303 && memcmp(cid->hash->data, cert_sha1, SHA_DIGEST_LENGTH) == 0) { 304 ESS_ISSUER_SERIAL *is = cid->issuer_serial; 305 if (!is || !ts_issuer_serial_cmp(is, cert)) 306 return i; 307 } 308 } 309 310 return -1; 311 } 312 313 /* Returns < 0 if certificate is not found, certificate index otherwise. */ 314 static int ts_find_cert_v2(STACK_OF(ESS_CERT_ID_V2) *cert_ids, X509 *cert) 315 { 316 int i; 317 unsigned char cert_digest[EVP_MAX_MD_SIZE]; 318 unsigned int len; 319 320 /* Look for cert in the cert_ids vector. */ 321 for (i = 0; i < sk_ESS_CERT_ID_V2_num(cert_ids); ++i) { 322 ESS_CERT_ID_V2 *cid = sk_ESS_CERT_ID_V2_value(cert_ids, i); 323 const EVP_MD *md; 324 325 if (cid->hash_alg != NULL) 326 md = EVP_get_digestbyobj(cid->hash_alg->algorithm); 327 else 328 md = EVP_sha256(); 329 330 if (!X509_digest(cert, md, cert_digest, &len)) 331 return -1; 332 if (cid->hash->length != (int)len) 333 return -1; 334 335 if (memcmp(cid->hash->data, cert_digest, cid->hash->length) == 0) { 336 ESS_ISSUER_SERIAL *is = cid->issuer_serial; 337 338 if (is == NULL || !ts_issuer_serial_cmp(is, cert)) 339 return i; 340 } 341 } 342 343 return -1; 344 } 345 346 static int ts_issuer_serial_cmp(ESS_ISSUER_SERIAL *is, X509 *cert) 347 { 348 GENERAL_NAME *issuer; 349 350 if (!is || !cert || sk_GENERAL_NAME_num(is->issuer) != 1) 351 return -1; 352 353 issuer = sk_GENERAL_NAME_value(is->issuer, 0); 354 if (issuer->type != GEN_DIRNAME 355 || X509_NAME_cmp(issuer->d.dirn, X509_get_issuer_name(cert))) 356 return -1; 357 358 if (ASN1_INTEGER_cmp(is->serial, X509_get_serialNumber(cert))) 359 return -1; 360 361 return 0; 362 } 363 364 /*- 365 * Verifies whether 'response' contains a valid response with regards 366 * to the settings of the context: 367 * - Gives an error message if the TS_TST_INFO is not present. 368 * - Calls _TS_RESP_verify_token to verify the token content. 369 */ 370 int TS_RESP_verify_response(TS_VERIFY_CTX *ctx, TS_RESP *response) 371 { 372 PKCS7 *token = response->token; 373 TS_TST_INFO *tst_info = response->tst_info; 374 int ret = 0; 375 376 if (!ts_check_status_info(response)) 377 goto err; 378 if (!int_ts_RESP_verify_token(ctx, token, tst_info)) 379 goto err; 380 ret = 1; 381 382 err: 383 return ret; 384 } 385 386 /* 387 * Tries to extract a TS_TST_INFO structure from the PKCS7 token and 388 * calls the internal int_TS_RESP_verify_token function for verifying it. 389 */ 390 int TS_RESP_verify_token(TS_VERIFY_CTX *ctx, PKCS7 *token) 391 { 392 TS_TST_INFO *tst_info = PKCS7_to_TS_TST_INFO(token); 393 int ret = 0; 394 if (tst_info) { 395 ret = int_ts_RESP_verify_token(ctx, token, tst_info); 396 TS_TST_INFO_free(tst_info); 397 } 398 return ret; 399 } 400 401 /*- 402 * Verifies whether the 'token' contains a valid time stamp token 403 * with regards to the settings of the context. Only those checks are 404 * carried out that are specified in the context: 405 * - Verifies the signature of the TS_TST_INFO. 406 * - Checks the version number of the response. 407 * - Check if the requested and returned policies math. 408 * - Check if the message imprints are the same. 409 * - Check if the nonces are the same. 410 * - Check if the TSA name matches the signer. 411 * - Check if the TSA name is the expected TSA. 412 */ 413 static int int_ts_RESP_verify_token(TS_VERIFY_CTX *ctx, 414 PKCS7 *token, TS_TST_INFO *tst_info) 415 { 416 X509 *signer = NULL; 417 GENERAL_NAME *tsa_name = tst_info->tsa; 418 X509_ALGOR *md_alg = NULL; 419 unsigned char *imprint = NULL; 420 unsigned imprint_len = 0; 421 int ret = 0; 422 int flags = ctx->flags; 423 424 /* Some options require us to also check the signature */ 425 if (((flags & TS_VFY_SIGNER) && tsa_name != NULL) 426 || (flags & TS_VFY_TSA_NAME)) { 427 flags |= TS_VFY_SIGNATURE; 428 } 429 430 if ((flags & TS_VFY_SIGNATURE) 431 && !TS_RESP_verify_signature(token, ctx->certs, ctx->store, &signer)) 432 goto err; 433 if ((flags & TS_VFY_VERSION) 434 && TS_TST_INFO_get_version(tst_info) != 1) { 435 TSerr(TS_F_INT_TS_RESP_VERIFY_TOKEN, TS_R_UNSUPPORTED_VERSION); 436 goto err; 437 } 438 if ((flags & TS_VFY_POLICY) 439 && !ts_check_policy(ctx->policy, tst_info)) 440 goto err; 441 if ((flags & TS_VFY_IMPRINT) 442 && !ts_check_imprints(ctx->md_alg, ctx->imprint, ctx->imprint_len, 443 tst_info)) 444 goto err; 445 if ((flags & TS_VFY_DATA) 446 && (!ts_compute_imprint(ctx->data, tst_info, 447 &md_alg, &imprint, &imprint_len) 448 || !ts_check_imprints(md_alg, imprint, imprint_len, tst_info))) 449 goto err; 450 if ((flags & TS_VFY_NONCE) 451 && !ts_check_nonces(ctx->nonce, tst_info)) 452 goto err; 453 if ((flags & TS_VFY_SIGNER) 454 && tsa_name && !ts_check_signer_name(tsa_name, signer)) { 455 TSerr(TS_F_INT_TS_RESP_VERIFY_TOKEN, TS_R_TSA_NAME_MISMATCH); 456 goto err; 457 } 458 if ((flags & TS_VFY_TSA_NAME) 459 && !ts_check_signer_name(ctx->tsa_name, signer)) { 460 TSerr(TS_F_INT_TS_RESP_VERIFY_TOKEN, TS_R_TSA_UNTRUSTED); 461 goto err; 462 } 463 ret = 1; 464 465 err: 466 X509_free(signer); 467 X509_ALGOR_free(md_alg); 468 OPENSSL_free(imprint); 469 return ret; 470 } 471 472 static int ts_check_status_info(TS_RESP *response) 473 { 474 TS_STATUS_INFO *info = response->status_info; 475 long status = ASN1_INTEGER_get(info->status); 476 const char *status_text = NULL; 477 char *embedded_status_text = NULL; 478 char failure_text[TS_STATUS_BUF_SIZE] = ""; 479 480 if (status == 0 || status == 1) 481 return 1; 482 483 /* There was an error, get the description in status_text. */ 484 if (0 <= status && status < (long) OSSL_NELEM(ts_status_text)) 485 status_text = ts_status_text[status]; 486 else 487 status_text = "unknown code"; 488 489 if (sk_ASN1_UTF8STRING_num(info->text) > 0 490 && (embedded_status_text = ts_get_status_text(info->text)) == NULL) 491 return 0; 492 493 /* Fill in failure_text with the failure information. */ 494 if (info->failure_info) { 495 int i; 496 int first = 1; 497 for (i = 0; i < (int)OSSL_NELEM(ts_failure_info); ++i) { 498 if (ASN1_BIT_STRING_get_bit(info->failure_info, 499 ts_failure_info[i].code)) { 500 if (!first) 501 strcat(failure_text, ","); 502 else 503 first = 0; 504 strcat(failure_text, ts_failure_info[i].text); 505 } 506 } 507 } 508 if (failure_text[0] == '\0') 509 strcpy(failure_text, "unspecified"); 510 511 TSerr(TS_F_TS_CHECK_STATUS_INFO, TS_R_NO_TIME_STAMP_TOKEN); 512 ERR_add_error_data(6, 513 "status code: ", status_text, 514 ", status text: ", embedded_status_text ? 515 embedded_status_text : "unspecified", 516 ", failure codes: ", failure_text); 517 OPENSSL_free(embedded_status_text); 518 519 return 0; 520 } 521 522 static char *ts_get_status_text(STACK_OF(ASN1_UTF8STRING) *text) 523 { 524 int i; 525 int length = 0; 526 char *result = NULL; 527 char *p; 528 529 for (i = 0; i < sk_ASN1_UTF8STRING_num(text); ++i) { 530 ASN1_UTF8STRING *current = sk_ASN1_UTF8STRING_value(text, i); 531 if (ASN1_STRING_length(current) > TS_MAX_STATUS_LENGTH - length - 1) 532 return NULL; 533 length += ASN1_STRING_length(current); 534 length += 1; /* separator character */ 535 } 536 if ((result = OPENSSL_malloc(length)) == NULL) { 537 TSerr(TS_F_TS_GET_STATUS_TEXT, ERR_R_MALLOC_FAILURE); 538 return NULL; 539 } 540 541 for (i = 0, p = result; i < sk_ASN1_UTF8STRING_num(text); ++i) { 542 ASN1_UTF8STRING *current = sk_ASN1_UTF8STRING_value(text, i); 543 length = ASN1_STRING_length(current); 544 if (i > 0) 545 *p++ = '/'; 546 strncpy(p, (const char *)ASN1_STRING_get0_data(current), length); 547 p += length; 548 } 549 *p = '\0'; 550 551 return result; 552 } 553 554 static int ts_check_policy(const ASN1_OBJECT *req_oid, 555 const TS_TST_INFO *tst_info) 556 { 557 const ASN1_OBJECT *resp_oid = tst_info->policy_id; 558 559 if (OBJ_cmp(req_oid, resp_oid) != 0) { 560 TSerr(TS_F_TS_CHECK_POLICY, TS_R_POLICY_MISMATCH); 561 return 0; 562 } 563 564 return 1; 565 } 566 567 static int ts_compute_imprint(BIO *data, TS_TST_INFO *tst_info, 568 X509_ALGOR **md_alg, 569 unsigned char **imprint, unsigned *imprint_len) 570 { 571 TS_MSG_IMPRINT *msg_imprint = tst_info->msg_imprint; 572 X509_ALGOR *md_alg_resp = msg_imprint->hash_algo; 573 const EVP_MD *md; 574 EVP_MD_CTX *md_ctx = NULL; 575 unsigned char buffer[4096]; 576 int length; 577 578 *md_alg = NULL; 579 *imprint = NULL; 580 581 if ((*md_alg = X509_ALGOR_dup(md_alg_resp)) == NULL) 582 goto err; 583 if ((md = EVP_get_digestbyobj((*md_alg)->algorithm)) == NULL) { 584 TSerr(TS_F_TS_COMPUTE_IMPRINT, TS_R_UNSUPPORTED_MD_ALGORITHM); 585 goto err; 586 } 587 length = EVP_MD_size(md); 588 if (length < 0) 589 goto err; 590 *imprint_len = length; 591 if ((*imprint = OPENSSL_malloc(*imprint_len)) == NULL) { 592 TSerr(TS_F_TS_COMPUTE_IMPRINT, ERR_R_MALLOC_FAILURE); 593 goto err; 594 } 595 596 md_ctx = EVP_MD_CTX_new(); 597 if (md_ctx == NULL) { 598 TSerr(TS_F_TS_COMPUTE_IMPRINT, ERR_R_MALLOC_FAILURE); 599 goto err; 600 } 601 if (!EVP_DigestInit(md_ctx, md)) 602 goto err; 603 while ((length = BIO_read(data, buffer, sizeof(buffer))) > 0) { 604 if (!EVP_DigestUpdate(md_ctx, buffer, length)) 605 goto err; 606 } 607 if (!EVP_DigestFinal(md_ctx, *imprint, NULL)) 608 goto err; 609 EVP_MD_CTX_free(md_ctx); 610 611 return 1; 612 err: 613 EVP_MD_CTX_free(md_ctx); 614 X509_ALGOR_free(*md_alg); 615 *md_alg = NULL; 616 OPENSSL_free(*imprint); 617 *imprint_len = 0; 618 *imprint = 0; 619 return 0; 620 } 621 622 static int ts_check_imprints(X509_ALGOR *algor_a, 623 const unsigned char *imprint_a, unsigned len_a, 624 TS_TST_INFO *tst_info) 625 { 626 TS_MSG_IMPRINT *b = tst_info->msg_imprint; 627 X509_ALGOR *algor_b = b->hash_algo; 628 int ret = 0; 629 630 if (algor_a) { 631 if (OBJ_cmp(algor_a->algorithm, algor_b->algorithm)) 632 goto err; 633 634 /* The parameter must be NULL in both. */ 635 if ((algor_a->parameter 636 && ASN1_TYPE_get(algor_a->parameter) != V_ASN1_NULL) 637 || (algor_b->parameter 638 && ASN1_TYPE_get(algor_b->parameter) != V_ASN1_NULL)) 639 goto err; 640 } 641 642 ret = len_a == (unsigned)ASN1_STRING_length(b->hashed_msg) && 643 memcmp(imprint_a, ASN1_STRING_get0_data(b->hashed_msg), len_a) == 0; 644 err: 645 if (!ret) 646 TSerr(TS_F_TS_CHECK_IMPRINTS, TS_R_MESSAGE_IMPRINT_MISMATCH); 647 return ret; 648 } 649 650 static int ts_check_nonces(const ASN1_INTEGER *a, TS_TST_INFO *tst_info) 651 { 652 const ASN1_INTEGER *b = tst_info->nonce; 653 654 if (!b) { 655 TSerr(TS_F_TS_CHECK_NONCES, TS_R_NONCE_NOT_RETURNED); 656 return 0; 657 } 658 659 /* No error if a nonce is returned without being requested. */ 660 if (ASN1_INTEGER_cmp(a, b) != 0) { 661 TSerr(TS_F_TS_CHECK_NONCES, TS_R_NONCE_MISMATCH); 662 return 0; 663 } 664 665 return 1; 666 } 667 668 /* 669 * Check if the specified TSA name matches either the subject or one of the 670 * subject alternative names of the TSA certificate. 671 */ 672 static int ts_check_signer_name(GENERAL_NAME *tsa_name, X509 *signer) 673 { 674 STACK_OF(GENERAL_NAME) *gen_names = NULL; 675 int idx = -1; 676 int found = 0; 677 678 if (tsa_name->type == GEN_DIRNAME 679 && X509_name_cmp(tsa_name->d.dirn, X509_get_subject_name(signer)) == 0) 680 return 1; 681 gen_names = X509_get_ext_d2i(signer, NID_subject_alt_name, NULL, &idx); 682 while (gen_names != NULL) { 683 found = ts_find_name(gen_names, tsa_name) >= 0; 684 if (found) 685 break; 686 /* 687 * Get the next subject alternative name, although there should be no 688 * more than one. 689 */ 690 GENERAL_NAMES_free(gen_names); 691 gen_names = X509_get_ext_d2i(signer, NID_subject_alt_name, NULL, &idx); 692 } 693 GENERAL_NAMES_free(gen_names); 694 695 return found; 696 } 697 698 /* Returns 1 if name is in gen_names, 0 otherwise. */ 699 static int ts_find_name(STACK_OF(GENERAL_NAME) *gen_names, GENERAL_NAME *name) 700 { 701 int i, found; 702 for (i = 0, found = 0; !found && i < sk_GENERAL_NAME_num(gen_names); ++i) { 703 GENERAL_NAME *current = sk_GENERAL_NAME_value(gen_names, i); 704 found = GENERAL_NAME_cmp(current, name) == 0; 705 } 706 return found ? i - 1 : -1; 707 } 708