1/* crypto/ts/ts_resp_verify.c */ 2/* 3 * Written by Zoltan Glozik (zglozik@stones.com) for the OpenSSL project 4 * 2002. 5 */ 6/* ==================================================================== 7 * Copyright (c) 2006 The OpenSSL Project. All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in 18 * the documentation and/or other materials provided with the 19 * distribution. 20 * 21 * 3. All advertising materials mentioning features or use of this 22 * software must display the following acknowledgment: 23 * "This product includes software developed by the OpenSSL Project 24 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" 25 * 26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 27 * endorse or promote products derived from this software without 28 * prior written permission. For written permission, please contact 29 * licensing@OpenSSL.org. 30 * 31 * 5. Products derived from this software may not be called "OpenSSL" 32 * nor may "OpenSSL" appear in their names without prior written 33 * permission of the OpenSSL Project. 34 * 35 * 6. Redistributions of any form whatsoever must retain the following 36 * acknowledgment: 37 * "This product includes software developed by the OpenSSL Project 38 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 39 * 40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 43 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 51 * OF THE POSSIBILITY OF SUCH DAMAGE. 52 * ==================================================================== 53 * 54 * This product includes cryptographic software written by Eric Young 55 * (eay@cryptsoft.com). This product includes software written by Tim 56 * Hudson (tjh@cryptsoft.com). 57 * 58 */ 59 60#include <stdio.h> 61#include "cryptlib.h" 62#include <openssl/objects.h> 63#include <openssl/ts.h> 64#include <openssl/pkcs7.h> 65 66/* Private function declarations. */ 67 68static int TS_verify_cert(X509_STORE *store, STACK_OF(X509) *untrusted, 69 X509 *signer, STACK_OF(X509) **chain); 70static int TS_check_signing_certs(PKCS7_SIGNER_INFO *si, 71 STACK_OF(X509) *chain); 72static ESS_SIGNING_CERT *ESS_get_signing_cert(PKCS7_SIGNER_INFO *si); 73static int TS_find_cert(STACK_OF(ESS_CERT_ID) *cert_ids, X509 *cert); 74static int TS_issuer_serial_cmp(ESS_ISSUER_SERIAL *is, X509_CINF *cinfo); 75static int int_TS_RESP_verify_token(TS_VERIFY_CTX *ctx, 76 PKCS7 *token, TS_TST_INFO *tst_info); 77static int TS_check_status_info(TS_RESP *response); 78static char *TS_get_status_text(STACK_OF(ASN1_UTF8STRING) *text); 79static int TS_check_policy(ASN1_OBJECT *req_oid, TS_TST_INFO *tst_info); 80static int TS_compute_imprint(BIO *data, TS_TST_INFO *tst_info, 81 X509_ALGOR **md_alg, 82 unsigned char **imprint, unsigned *imprint_len); 83static int TS_check_imprints(X509_ALGOR *algor_a, 84 unsigned char *imprint_a, unsigned len_a, 85 TS_TST_INFO *tst_info); 86static int TS_check_nonces(const ASN1_INTEGER *a, TS_TST_INFO *tst_info); 87static int TS_check_signer_name(GENERAL_NAME *tsa_name, X509 *signer); 88static int TS_find_name(STACK_OF(GENERAL_NAME) *gen_names, 89 GENERAL_NAME *name); 90 91/* 92 * Local mapping between response codes and descriptions. 93 * Don't forget to change TS_STATUS_BUF_SIZE when modifying 94 * the elements of this array. 95 */ 96static const char *TS_status_text[] = { "granted", 97 "grantedWithMods", 98 "rejection", 99 "waiting", 100 "revocationWarning", 101 "revocationNotification" 102}; 103 104#define TS_STATUS_TEXT_SIZE (sizeof(TS_status_text)/sizeof(*TS_status_text)) 105 106/* 107 * This must be greater or equal to the sum of the strings in TS_status_text 108 * plus the number of its elements. 109 */ 110#define TS_STATUS_BUF_SIZE 256 111 112static struct { 113 int code; 114 const char *text; 115} TS_failure_info[] = { 116 { 117 TS_INFO_BAD_ALG, "badAlg" 118 }, 119 { 120 TS_INFO_BAD_REQUEST, "badRequest" 121 }, 122 { 123 TS_INFO_BAD_DATA_FORMAT, "badDataFormat" 124 }, 125 { 126 TS_INFO_TIME_NOT_AVAILABLE, "timeNotAvailable" 127 }, 128 { 129 TS_INFO_UNACCEPTED_POLICY, "unacceptedPolicy" 130 }, 131 { 132 TS_INFO_UNACCEPTED_EXTENSION, "unacceptedExtension" 133 }, 134 { 135 TS_INFO_ADD_INFO_NOT_AVAILABLE, "addInfoNotAvailable" 136 }, 137 { 138 TS_INFO_SYSTEM_FAILURE, "systemFailure" 139 } 140}; 141 142#define TS_FAILURE_INFO_SIZE (sizeof(TS_failure_info) / \ 143 sizeof(*TS_failure_info)) 144 145/* Functions for verifying a signed TS_TST_INFO structure. */ 146 147/*- 148 * This function carries out the following tasks: 149 * - Checks if there is one and only one signer. 150 * - Search for the signing certificate in 'certs' and in the response. 151 * - Check the extended key usage and key usage fields of the signer 152 * certificate (done by the path validation). 153 * - Build and validate the certificate path. 154 * - Check if the certificate path meets the requirements of the 155 * SigningCertificate ESS signed attribute. 156 * - Verify the signature value. 157 * - Returns the signer certificate in 'signer', if 'signer' is not NULL. 158 */ 159int TS_RESP_verify_signature(PKCS7 *token, STACK_OF(X509) *certs, 160 X509_STORE *store, X509 **signer_out) 161{ 162 STACK_OF(PKCS7_SIGNER_INFO) *sinfos = NULL; 163 PKCS7_SIGNER_INFO *si; 164 STACK_OF(X509) *signers = NULL; 165 X509 *signer; 166 STACK_OF(X509) *chain = NULL; 167 char buf[4096]; 168 int i, j = 0, ret = 0; 169 BIO *p7bio = NULL; 170 171 /* Some sanity checks first. */ 172 if (!token) { 173 TSerr(TS_F_TS_RESP_VERIFY_SIGNATURE, TS_R_INVALID_NULL_POINTER); 174 goto err; 175 } 176 177 /* Check for the correct content type */ 178 if (!PKCS7_type_is_signed(token)) { 179 TSerr(TS_F_TS_RESP_VERIFY_SIGNATURE, TS_R_WRONG_CONTENT_TYPE); 180 goto err; 181 } 182 183 /* Check if there is one and only one signer. */ 184 sinfos = PKCS7_get_signer_info(token); 185 if (!sinfos || sk_PKCS7_SIGNER_INFO_num(sinfos) != 1) { 186 TSerr(TS_F_TS_RESP_VERIFY_SIGNATURE, TS_R_THERE_MUST_BE_ONE_SIGNER); 187 goto err; 188 } 189 si = sk_PKCS7_SIGNER_INFO_value(sinfos, 0); 190 191 /* Check for no content: no data to verify signature. */ 192 if (PKCS7_get_detached(token)) { 193 TSerr(TS_F_TS_RESP_VERIFY_SIGNATURE, TS_R_NO_CONTENT); 194 goto err; 195 } 196 197 /* 198 * Get hold of the signer certificate, search only internal certificates 199 * if it was requested. 200 */ 201 signers = PKCS7_get0_signers(token, certs, 0); 202 if (!signers || sk_X509_num(signers) != 1) 203 goto err; 204 signer = sk_X509_value(signers, 0); 205 206 /* Now verify the certificate. */ 207 if (!TS_verify_cert(store, certs, signer, &chain)) 208 goto err; 209 210 /* 211 * Check if the signer certificate is consistent with the ESS extension. 212 */ 213 if (!TS_check_signing_certs(si, chain)) 214 goto err; 215 216 /* Creating the message digest. */ 217 p7bio = PKCS7_dataInit(token, NULL); 218 219 /* We now have to 'read' from p7bio to calculate digests etc. */ 220 while ((i = BIO_read(p7bio, buf, sizeof(buf))) > 0) ; 221 222 /* Verifying the signature. */ 223 j = PKCS7_signatureVerify(p7bio, token, si, signer); 224 if (j <= 0) { 225 TSerr(TS_F_TS_RESP_VERIFY_SIGNATURE, TS_R_SIGNATURE_FAILURE); 226 goto err; 227 } 228 229 /* Return the signer certificate if needed. */ 230 if (signer_out) { 231 *signer_out = signer; 232 CRYPTO_add(&signer->references, 1, CRYPTO_LOCK_X509); 233 } 234 235 ret = 1; 236 237 err: 238 BIO_free_all(p7bio); 239 sk_X509_pop_free(chain, X509_free); 240 sk_X509_free(signers); 241 242 return ret; 243} 244 245/* 246 * The certificate chain is returned in chain. Caller is responsible for 247 * freeing the vector. 248 */ 249static int TS_verify_cert(X509_STORE *store, STACK_OF(X509) *untrusted, 250 X509 *signer, STACK_OF(X509) **chain) 251{ 252 X509_STORE_CTX cert_ctx; 253 int i; 254 int ret = 1; 255 256 /* chain is an out argument. */ 257 *chain = NULL; 258 if (!X509_STORE_CTX_init(&cert_ctx, store, signer, untrusted)) 259 return 0; 260 X509_STORE_CTX_set_purpose(&cert_ctx, X509_PURPOSE_TIMESTAMP_SIGN); 261 i = X509_verify_cert(&cert_ctx); 262 if (i <= 0) { 263 int j = X509_STORE_CTX_get_error(&cert_ctx); 264 TSerr(TS_F_TS_VERIFY_CERT, TS_R_CERTIFICATE_VERIFY_ERROR); 265 ERR_add_error_data(2, "Verify error:", 266 X509_verify_cert_error_string(j)); 267 ret = 0; 268 } else { 269 /* Get a copy of the certificate chain. */ 270 *chain = X509_STORE_CTX_get1_chain(&cert_ctx); 271 } 272 273 X509_STORE_CTX_cleanup(&cert_ctx); 274 275 return ret; 276} 277 278static int TS_check_signing_certs(PKCS7_SIGNER_INFO *si, 279 STACK_OF(X509) *chain) 280{ 281 ESS_SIGNING_CERT *ss = ESS_get_signing_cert(si); 282 STACK_OF(ESS_CERT_ID) *cert_ids = NULL; 283 X509 *cert; 284 int i = 0; 285 int ret = 0; 286 287 if (!ss) 288 goto err; 289 cert_ids = ss->cert_ids; 290 /* The signer certificate must be the first in cert_ids. */ 291 cert = sk_X509_value(chain, 0); 292 if (TS_find_cert(cert_ids, cert) != 0) 293 goto err; 294 295 /* 296 * Check the other certificates of the chain if there are more than one 297 * certificate ids in cert_ids. 298 */ 299 if (sk_ESS_CERT_ID_num(cert_ids) > 1) { 300 /* All the certificates of the chain must be in cert_ids. */ 301 for (i = 1; i < sk_X509_num(chain); ++i) { 302 cert = sk_X509_value(chain, i); 303 if (TS_find_cert(cert_ids, cert) < 0) 304 goto err; 305 } 306 } 307 ret = 1; 308 err: 309 if (!ret) 310 TSerr(TS_F_TS_CHECK_SIGNING_CERTS, 311 TS_R_ESS_SIGNING_CERTIFICATE_ERROR); 312 ESS_SIGNING_CERT_free(ss); 313 return ret; 314} 315 316static ESS_SIGNING_CERT *ESS_get_signing_cert(PKCS7_SIGNER_INFO *si) 317{ 318 ASN1_TYPE *attr; 319 const unsigned char *p; 320 attr = PKCS7_get_signed_attribute(si, NID_id_smime_aa_signingCertificate); 321 if (!attr) 322 return NULL; 323 p = attr->value.sequence->data; 324 return d2i_ESS_SIGNING_CERT(NULL, &p, attr->value.sequence->length); 325} 326 327/* Returns < 0 if certificate is not found, certificate index otherwise. */ 328static int TS_find_cert(STACK_OF(ESS_CERT_ID) *cert_ids, X509 *cert) 329{ 330 int i; 331 332 if (!cert_ids || !cert) 333 return -1; 334 335 /* Recompute SHA1 hash of certificate if necessary (side effect). */ 336 X509_check_purpose(cert, -1, 0); 337 338 /* Look for cert in the cert_ids vector. */ 339 for (i = 0; i < sk_ESS_CERT_ID_num(cert_ids); ++i) { 340 ESS_CERT_ID *cid = sk_ESS_CERT_ID_value(cert_ids, i); 341 342 /* Check the SHA-1 hash first. */ 343 if (cid->hash->length == sizeof(cert->sha1_hash) 344 && !memcmp(cid->hash->data, cert->sha1_hash, 345 sizeof(cert->sha1_hash))) { 346 /* Check the issuer/serial as well if specified. */ 347 ESS_ISSUER_SERIAL *is = cid->issuer_serial; 348 if (!is || !TS_issuer_serial_cmp(is, cert->cert_info)) 349 return i; 350 } 351 } 352 353 return -1; 354} 355 356static int TS_issuer_serial_cmp(ESS_ISSUER_SERIAL *is, X509_CINF *cinfo) 357{ 358 GENERAL_NAME *issuer; 359 360 if (!is || !cinfo || sk_GENERAL_NAME_num(is->issuer) != 1) 361 return -1; 362 363 /* Check the issuer first. It must be a directory name. */ 364 issuer = sk_GENERAL_NAME_value(is->issuer, 0); 365 if (issuer->type != GEN_DIRNAME 366 || X509_NAME_cmp(issuer->d.dirn, cinfo->issuer)) 367 return -1; 368 369 /* Check the serial number, too. */ 370 if (ASN1_INTEGER_cmp(is->serial, cinfo->serialNumber)) 371 return -1; 372 373 return 0; 374} 375 376/*- 377 * Verifies whether 'response' contains a valid response with regards 378 * to the settings of the context: 379 * - Gives an error message if the TS_TST_INFO is not present. 380 * - Calls _TS_RESP_verify_token to verify the token content. 381 */ 382int TS_RESP_verify_response(TS_VERIFY_CTX *ctx, TS_RESP *response) 383{ 384 PKCS7 *token = TS_RESP_get_token(response); 385 TS_TST_INFO *tst_info = TS_RESP_get_tst_info(response); 386 int ret = 0; 387 388 /* Check if we have a successful TS_TST_INFO object in place. */ 389 if (!TS_check_status_info(response)) 390 goto err; 391 392 /* Check the contents of the time stamp token. */ 393 if (!int_TS_RESP_verify_token(ctx, token, tst_info)) 394 goto err; 395 396 ret = 1; 397 err: 398 return ret; 399} 400 401/* 402 * Tries to extract a TS_TST_INFO structure from the PKCS7 token and 403 * calls the internal int_TS_RESP_verify_token function for verifying it. 404 */ 405int TS_RESP_verify_token(TS_VERIFY_CTX *ctx, PKCS7 *token) 406{ 407 TS_TST_INFO *tst_info = PKCS7_to_TS_TST_INFO(token); 408 int ret = 0; 409 if (tst_info) { 410 ret = int_TS_RESP_verify_token(ctx, token, tst_info); 411 TS_TST_INFO_free(tst_info); 412 } 413 return ret; 414} 415 416/*- 417 * Verifies whether the 'token' contains a valid time stamp token 418 * with regards to the settings of the context. Only those checks are 419 * carried out that are specified in the context: 420 * - Verifies the signature of the TS_TST_INFO. 421 * - Checks the version number of the response. 422 * - Check if the requested and returned policies math. 423 * - Check if the message imprints are the same. 424 * - Check if the nonces are the same. 425 * - Check if the TSA name matches the signer. 426 * - Check if the TSA name is the expected TSA. 427 */ 428static int int_TS_RESP_verify_token(TS_VERIFY_CTX *ctx, 429 PKCS7 *token, TS_TST_INFO *tst_info) 430{ 431 X509 *signer = NULL; 432 GENERAL_NAME *tsa_name = TS_TST_INFO_get_tsa(tst_info); 433 X509_ALGOR *md_alg = NULL; 434 unsigned char *imprint = NULL; 435 unsigned imprint_len = 0; 436 int ret = 0; 437 438 /* Verify the signature. */ 439 if ((ctx->flags & TS_VFY_SIGNATURE) 440 && !TS_RESP_verify_signature(token, ctx->certs, ctx->store, &signer)) 441 goto err; 442 443 /* Check version number of response. */ 444 if ((ctx->flags & TS_VFY_VERSION) 445 && TS_TST_INFO_get_version(tst_info) != 1) { 446 TSerr(TS_F_INT_TS_RESP_VERIFY_TOKEN, TS_R_UNSUPPORTED_VERSION); 447 goto err; 448 } 449 450 /* Check policies. */ 451 if ((ctx->flags & TS_VFY_POLICY) 452 && !TS_check_policy(ctx->policy, tst_info)) 453 goto err; 454 455 /* Check message imprints. */ 456 if ((ctx->flags & TS_VFY_IMPRINT) 457 && !TS_check_imprints(ctx->md_alg, ctx->imprint, ctx->imprint_len, 458 tst_info)) 459 goto err; 460 461 /* Compute and check message imprints. */ 462 if ((ctx->flags & TS_VFY_DATA) 463 && (!TS_compute_imprint(ctx->data, tst_info, 464 &md_alg, &imprint, &imprint_len) 465 || !TS_check_imprints(md_alg, imprint, imprint_len, tst_info))) 466 goto err; 467 468 /* Check nonces. */ 469 if ((ctx->flags & TS_VFY_NONCE) 470 && !TS_check_nonces(ctx->nonce, tst_info)) 471 goto err; 472 473 /* Check whether TSA name and signer certificate match. */ 474 if ((ctx->flags & TS_VFY_SIGNER) 475 && tsa_name && !TS_check_signer_name(tsa_name, signer)) { 476 TSerr(TS_F_INT_TS_RESP_VERIFY_TOKEN, TS_R_TSA_NAME_MISMATCH); 477 goto err; 478 } 479 480 /* Check whether the TSA is the expected one. */ 481 if ((ctx->flags & TS_VFY_TSA_NAME) 482 && !TS_check_signer_name(ctx->tsa_name, signer)) { 483 TSerr(TS_F_INT_TS_RESP_VERIFY_TOKEN, TS_R_TSA_UNTRUSTED); 484 goto err; 485 } 486 487 ret = 1; 488 err: 489 X509_free(signer); 490 X509_ALGOR_free(md_alg); 491 OPENSSL_free(imprint); 492 return ret; 493} 494 495static int TS_check_status_info(TS_RESP *response) 496{ 497 TS_STATUS_INFO *info = TS_RESP_get_status_info(response); 498 long status = ASN1_INTEGER_get(info->status); 499 const char *status_text = NULL; 500 char *embedded_status_text = NULL; 501 char failure_text[TS_STATUS_BUF_SIZE] = ""; 502 503 /* Check if everything went fine. */ 504 if (status == 0 || status == 1) 505 return 1; 506 507 /* There was an error, get the description in status_text. */ 508 if (0 <= status && status < (long)TS_STATUS_TEXT_SIZE) 509 status_text = TS_status_text[status]; 510 else 511 status_text = "unknown code"; 512 513 /* Set the embedded_status_text to the returned description. */ 514 if (sk_ASN1_UTF8STRING_num(info->text) > 0 515 && !(embedded_status_text = TS_get_status_text(info->text))) 516 return 0; 517 518 /* Filling in failure_text with the failure information. */ 519 if (info->failure_info) { 520 int i; 521 int first = 1; 522 for (i = 0; i < (int)TS_FAILURE_INFO_SIZE; ++i) { 523 if (ASN1_BIT_STRING_get_bit(info->failure_info, 524 TS_failure_info[i].code)) { 525 if (!first) 526 strcat(failure_text, ","); 527 else 528 first = 0; 529 strcat(failure_text, TS_failure_info[i].text); 530 } 531 } 532 } 533 if (failure_text[0] == '\0') 534 strcpy(failure_text, "unspecified"); 535 536 /* Making up the error string. */ 537 TSerr(TS_F_TS_CHECK_STATUS_INFO, TS_R_NO_TIME_STAMP_TOKEN); 538 ERR_add_error_data(6, 539 "status code: ", status_text, 540 ", status text: ", embedded_status_text ? 541 embedded_status_text : "unspecified", 542 ", failure codes: ", failure_text); 543 OPENSSL_free(embedded_status_text); 544 545 return 0; 546} 547 548static char *TS_get_status_text(STACK_OF(ASN1_UTF8STRING) *text) 549{ 550 int i; 551 unsigned int length = 0; 552 char *result = NULL; 553 char *p; 554 555 /* Determine length first. */ 556 for (i = 0; i < sk_ASN1_UTF8STRING_num(text); ++i) { 557 ASN1_UTF8STRING *current = sk_ASN1_UTF8STRING_value(text, i); 558 length += ASN1_STRING_length(current); 559 length += 1; /* separator character */ 560 } 561 /* Allocate memory (closing '\0' included). */ 562 if (!(result = OPENSSL_malloc(length))) { 563 TSerr(TS_F_TS_GET_STATUS_TEXT, ERR_R_MALLOC_FAILURE); 564 return NULL; 565 } 566 /* Concatenate the descriptions. */ 567 for (i = 0, p = result; i < sk_ASN1_UTF8STRING_num(text); ++i) { 568 ASN1_UTF8STRING *current = sk_ASN1_UTF8STRING_value(text, i); 569 length = ASN1_STRING_length(current); 570 if (i > 0) 571 *p++ = '/'; 572 strncpy(p, (const char *)ASN1_STRING_data(current), length); 573 p += length; 574 } 575 /* We do have space for this, too. */ 576 *p = '\0'; 577 578 return result; 579} 580 581static int TS_check_policy(ASN1_OBJECT *req_oid, TS_TST_INFO *tst_info) 582{ 583 ASN1_OBJECT *resp_oid = TS_TST_INFO_get_policy_id(tst_info); 584 585 if (OBJ_cmp(req_oid, resp_oid) != 0) { 586 TSerr(TS_F_TS_CHECK_POLICY, TS_R_POLICY_MISMATCH); 587 return 0; 588 } 589 590 return 1; 591} 592 593static int TS_compute_imprint(BIO *data, TS_TST_INFO *tst_info, 594 X509_ALGOR **md_alg, 595 unsigned char **imprint, unsigned *imprint_len) 596{ 597 TS_MSG_IMPRINT *msg_imprint = TS_TST_INFO_get_msg_imprint(tst_info); 598 X509_ALGOR *md_alg_resp = TS_MSG_IMPRINT_get_algo(msg_imprint); 599 const EVP_MD *md; 600 EVP_MD_CTX md_ctx; 601 unsigned char buffer[4096]; 602 int length; 603 604 *md_alg = NULL; 605 *imprint = NULL; 606 607 /* Return the MD algorithm of the response. */ 608 if (!(*md_alg = X509_ALGOR_dup(md_alg_resp))) 609 goto err; 610 611 /* Getting the MD object. */ 612 if (!(md = EVP_get_digestbyobj((*md_alg)->algorithm))) { 613 TSerr(TS_F_TS_COMPUTE_IMPRINT, TS_R_UNSUPPORTED_MD_ALGORITHM); 614 goto err; 615 } 616 617 /* Compute message digest. */ 618 length = EVP_MD_size(md); 619 if (length < 0) 620 goto err; 621 *imprint_len = length; 622 if (!(*imprint = OPENSSL_malloc(*imprint_len))) { 623 TSerr(TS_F_TS_COMPUTE_IMPRINT, ERR_R_MALLOC_FAILURE); 624 goto err; 625 } 626 627 if (!EVP_DigestInit(&md_ctx, md)) 628 goto err; 629 while ((length = BIO_read(data, buffer, sizeof(buffer))) > 0) { 630 if (!EVP_DigestUpdate(&md_ctx, buffer, length)) 631 goto err; 632 } 633 if (!EVP_DigestFinal(&md_ctx, *imprint, NULL)) 634 goto err; 635 636 return 1; 637 err: 638 X509_ALGOR_free(*md_alg); 639 OPENSSL_free(*imprint); 640 *imprint_len = 0; 641 *imprint = 0; 642 return 0; 643} 644 645static int TS_check_imprints(X509_ALGOR *algor_a, 646 unsigned char *imprint_a, unsigned len_a, 647 TS_TST_INFO *tst_info) 648{ 649 TS_MSG_IMPRINT *b = TS_TST_INFO_get_msg_imprint(tst_info); 650 X509_ALGOR *algor_b = TS_MSG_IMPRINT_get_algo(b); 651 int ret = 0; 652 653 /* algor_a is optional. */ 654 if (algor_a) { 655 /* Compare algorithm OIDs. */ 656 if (OBJ_cmp(algor_a->algorithm, algor_b->algorithm)) 657 goto err; 658 659 /* The parameter must be NULL in both. */ 660 if ((algor_a->parameter 661 && ASN1_TYPE_get(algor_a->parameter) != V_ASN1_NULL) 662 || (algor_b->parameter 663 && ASN1_TYPE_get(algor_b->parameter) != V_ASN1_NULL)) 664 goto err; 665 } 666 667 /* Compare octet strings. */ 668 ret = len_a == (unsigned)ASN1_STRING_length(b->hashed_msg) && 669 memcmp(imprint_a, ASN1_STRING_data(b->hashed_msg), len_a) == 0; 670 err: 671 if (!ret) 672 TSerr(TS_F_TS_CHECK_IMPRINTS, TS_R_MESSAGE_IMPRINT_MISMATCH); 673 return ret; 674} 675 676static int TS_check_nonces(const ASN1_INTEGER *a, TS_TST_INFO *tst_info) 677{ 678 const ASN1_INTEGER *b = TS_TST_INFO_get_nonce(tst_info); 679 680 /* Error if nonce is missing. */ 681 if (!b) { 682 TSerr(TS_F_TS_CHECK_NONCES, TS_R_NONCE_NOT_RETURNED); 683 return 0; 684 } 685 686 /* No error if a nonce is returned without being requested. */ 687 if (ASN1_INTEGER_cmp(a, b) != 0) { 688 TSerr(TS_F_TS_CHECK_NONCES, TS_R_NONCE_MISMATCH); 689 return 0; 690 } 691 692 return 1; 693} 694 695/* 696 * Check if the specified TSA name matches either the subject or one of the 697 * subject alternative names of the TSA certificate. 698 */ 699static int TS_check_signer_name(GENERAL_NAME *tsa_name, X509 *signer) 700{ 701 STACK_OF(GENERAL_NAME) *gen_names = NULL; 702 int idx = -1; 703 int found = 0; 704 705 /* Check the subject name first. */ 706 if (tsa_name->type == GEN_DIRNAME 707 && X509_name_cmp(tsa_name->d.dirn, signer->cert_info->subject) == 0) 708 return 1; 709 710 /* Check all the alternative names. */ 711 gen_names = X509_get_ext_d2i(signer, NID_subject_alt_name, NULL, &idx); 712 while (gen_names != NULL 713 && !(found = TS_find_name(gen_names, tsa_name) >= 0)) { 714 /* 715 * Get the next subject alternative name, although there should be no 716 * more than one. 717 */ 718 GENERAL_NAMES_free(gen_names); 719 gen_names = X509_get_ext_d2i(signer, NID_subject_alt_name, 720 NULL, &idx); 721 } 722 if (gen_names) 723 GENERAL_NAMES_free(gen_names); 724 725 return found; 726} 727 728/* Returns 1 if name is in gen_names, 0 otherwise. */ 729static int TS_find_name(STACK_OF(GENERAL_NAME) *gen_names, GENERAL_NAME *name) 730{ 731 int i, found; 732 for (i = 0, found = 0; !found && i < sk_GENERAL_NAME_num(gen_names); ++i) { 733 GENERAL_NAME *current = sk_GENERAL_NAME_value(gen_names, i); 734 found = GENERAL_NAME_cmp(current, name) == 0; 735 } 736 return found ? i - 1 : -1; 737} 738