1/* 2 * Copyright 2007-2023 The OpenSSL Project Authors. All Rights Reserved. 3 * Copyright Nokia 2007-2020 4 * Copyright Siemens AG 2015-2020 5 * 6 * Licensed under the Apache License 2.0 (the "License"). You may not use 7 * this file except in compliance with the License. You can obtain a copy 8 * in the file LICENSE in the source distribution or at 9 * https://www.openssl.org/source/license.html 10 */ 11 12/* CMP functions for PKIMessage checking */ 13 14#include "cmp_local.h" 15#include <openssl/cmp_util.h> 16 17/* explicit #includes not strictly needed since implied by the above: */ 18#include <openssl/asn1t.h> 19#include <openssl/cmp.h> 20#include <openssl/crmf.h> 21#include <openssl/err.h> 22#include <openssl/x509.h> 23 24/* Verify a message protected by signature according to RFC section 5.1.3.3 */ 25static int verify_signature(const OSSL_CMP_CTX *cmp_ctx, 26 const OSSL_CMP_MSG *msg, X509 *cert) 27{ 28 OSSL_CMP_PROTECTEDPART prot_part; 29 EVP_PKEY *pubkey = NULL; 30 BIO *bio; 31 int res = 0; 32 33 if (!ossl_assert(cmp_ctx != NULL && msg != NULL && cert != NULL)) 34 return 0; 35 36 bio = BIO_new(BIO_s_mem()); /* may be NULL */ 37 38 /* verify that keyUsage, if present, contains digitalSignature */ 39 if (!cmp_ctx->ignore_keyusage 40 && (X509_get_key_usage(cert) & X509v3_KU_DIGITAL_SIGNATURE) == 0) { 41 ERR_raise(ERR_LIB_CMP, CMP_R_MISSING_KEY_USAGE_DIGITALSIGNATURE); 42 goto sig_err; 43 } 44 45 pubkey = X509_get_pubkey(cert); 46 if (pubkey == NULL) { 47 ERR_raise(ERR_LIB_CMP, CMP_R_FAILED_EXTRACTING_PUBKEY); 48 goto sig_err; 49 } 50 51 prot_part.header = msg->header; 52 prot_part.body = msg->body; 53 54 if (ASN1_item_verify_ex(ASN1_ITEM_rptr(OSSL_CMP_PROTECTEDPART), 55 msg->header->protectionAlg, msg->protection, 56 &prot_part, NULL, pubkey, cmp_ctx->libctx, 57 cmp_ctx->propq) > 0) { 58 res = 1; 59 goto end; 60 } 61 62 sig_err: 63 res = ossl_x509_print_ex_brief(bio, cert, X509_FLAG_NO_EXTENSIONS); 64 ERR_raise(ERR_LIB_CMP, CMP_R_ERROR_VALIDATING_SIGNATURE); 65 if (res) 66 ERR_add_error_mem_bio("\n", bio); 67 res = 0; 68 69 end: 70 EVP_PKEY_free(pubkey); 71 BIO_free(bio); 72 73 return res; 74} 75 76/* Verify a message protected with PBMAC */ 77static int verify_PBMAC(OSSL_CMP_CTX *ctx, const OSSL_CMP_MSG *msg) 78{ 79 ASN1_BIT_STRING *protection = NULL; 80 int valid = 0; 81 82 /* generate expected protection for the message */ 83 if ((protection = ossl_cmp_calc_protection(ctx, msg)) == NULL) 84 return 0; /* failed to generate protection string! */ 85 86 valid = msg->protection != NULL && msg->protection->length >= 0 87 && msg->protection->type == protection->type 88 && msg->protection->length == protection->length 89 && CRYPTO_memcmp(msg->protection->data, protection->data, 90 protection->length) == 0; 91 ASN1_BIT_STRING_free(protection); 92 if (!valid) 93 ERR_raise(ERR_LIB_CMP, CMP_R_WRONG_PBM_VALUE); 94 95 return valid; 96} 97 98/*- 99 * Attempt to validate certificate and path using any given store with trusted 100 * certs (possibly including CRLs and a cert verification callback function) 101 * and non-trusted intermediate certs from the given ctx. 102 * 103 * Returns 1 on successful validation and 0 otherwise. 104 */ 105int OSSL_CMP_validate_cert_path(const OSSL_CMP_CTX *ctx, 106 X509_STORE *trusted_store, X509 *cert) 107{ 108 int valid = 0; 109 X509_STORE_CTX *csc = NULL; 110 int err; 111 112 if (ctx == NULL || cert == NULL) { 113 ERR_raise(ERR_LIB_CMP, CMP_R_NULL_ARGUMENT); 114 return 0; 115 } 116 117 if (trusted_store == NULL) { 118 ERR_raise(ERR_LIB_CMP, CMP_R_MISSING_TRUST_STORE); 119 return 0; 120 } 121 122 if ((csc = X509_STORE_CTX_new_ex(ctx->libctx, ctx->propq)) == NULL 123 || !X509_STORE_CTX_init(csc, trusted_store, 124 cert, ctx->untrusted)) 125 goto err; 126 127 valid = X509_verify_cert(csc) > 0; 128 129 /* make sure suitable error is queued even if callback did not do */ 130 err = ERR_peek_last_error(); 131 if (!valid && ERR_GET_REASON(err) != CMP_R_POTENTIALLY_INVALID_CERTIFICATE) 132 ERR_raise(ERR_LIB_CMP, CMP_R_POTENTIALLY_INVALID_CERTIFICATE); 133 134 err: 135 /* directly output any fresh errors, needed for check_msg_find_cert() */ 136 OSSL_CMP_CTX_print_errors(ctx); 137 X509_STORE_CTX_free(csc); 138 return valid; 139} 140 141/* Return 0 if expect_name != NULL and there is no matching actual_name */ 142static int check_name(const OSSL_CMP_CTX *ctx, int log_success, 143 const char *actual_desc, const X509_NAME *actual_name, 144 const char *expect_desc, const X509_NAME *expect_name) 145{ 146 char *str; 147 148 if (expect_name == NULL) 149 return 1; /* no expectation, thus trivially fulfilled */ 150 151 /* make sure that a matching name is there */ 152 if (actual_name == NULL) { 153 ossl_cmp_log1(WARN, ctx, "missing %s", actual_desc); 154 return 0; 155 } 156 str = X509_NAME_oneline(actual_name, NULL, 0); 157 if (X509_NAME_cmp(actual_name, expect_name) == 0) { 158 if (log_success && str != NULL) 159 ossl_cmp_log2(INFO, ctx, " subject matches %s: %s", expect_desc, 160 str); 161 OPENSSL_free(str); 162 return 1; 163 } 164 165 if (str != NULL) 166 ossl_cmp_log2(INFO, ctx, " actual name in %s = %s", actual_desc, str); 167 OPENSSL_free(str); 168 if ((str = X509_NAME_oneline(expect_name, NULL, 0)) != NULL) 169 ossl_cmp_log2(INFO, ctx, " does not match %s = %s", expect_desc, str); 170 OPENSSL_free(str); 171 return 0; 172} 173 174/* Return 0 if skid != NULL and there is no matching subject key ID in cert */ 175static int check_kid(const OSSL_CMP_CTX *ctx, 176 const ASN1_OCTET_STRING *ckid, 177 const ASN1_OCTET_STRING *skid) 178{ 179 char *str; 180 181 if (skid == NULL) 182 return 1; /* no expectation, thus trivially fulfilled */ 183 184 /* make sure that the expected subject key identifier is there */ 185 if (ckid == NULL) { 186 ossl_cmp_warn(ctx, "missing Subject Key Identifier in certificate"); 187 return 0; 188 } 189 str = OPENSSL_buf2hexstr(ckid->data, ckid->length); 190 if (ASN1_OCTET_STRING_cmp(ckid, skid) == 0) { 191 if (str != NULL) 192 ossl_cmp_log1(INFO, ctx, " subjectKID matches senderKID: %s", str); 193 OPENSSL_free(str); 194 return 1; 195 } 196 197 if (str != NULL) 198 ossl_cmp_log1(INFO, ctx, " cert Subject Key Identifier = %s", str); 199 OPENSSL_free(str); 200 if ((str = OPENSSL_buf2hexstr(skid->data, skid->length)) != NULL) 201 ossl_cmp_log1(INFO, ctx, " does not match senderKID = %s", str); 202 OPENSSL_free(str); 203 return 0; 204} 205 206static int already_checked(const X509 *cert, 207 const STACK_OF(X509) *already_checked) 208{ 209 int i; 210 211 for (i = sk_X509_num(already_checked /* may be NULL */); i > 0; i--) 212 if (X509_cmp(sk_X509_value(already_checked, i - 1), cert) == 0) 213 return 1; 214 return 0; 215} 216 217/*- 218 * Check if the given cert is acceptable as sender cert of the given message. 219 * The subject DN must match, the subject key ID as well if present in the msg, 220 * and the cert must be current (checked if ctx->trusted is not NULL). 221 * Note that cert revocation etc. is checked by OSSL_CMP_validate_cert_path(). 222 * 223 * Returns 0 on error or not acceptable, else 1. 224 */ 225static int cert_acceptable(const OSSL_CMP_CTX *ctx, 226 const char *desc1, const char *desc2, X509 *cert, 227 const STACK_OF(X509) *already_checked1, 228 const STACK_OF(X509) *already_checked2, 229 const OSSL_CMP_MSG *msg) 230{ 231 X509_STORE *ts = ctx->trusted; 232 int self_issued = X509_check_issued(cert, cert) == X509_V_OK; 233 char *str; 234 X509_VERIFY_PARAM *vpm = ts != NULL ? X509_STORE_get0_param(ts) : NULL; 235 int time_cmp; 236 237 ossl_cmp_log3(INFO, ctx, " considering %s%s %s with..", 238 self_issued ? "self-issued ": "", desc1, desc2); 239 if ((str = X509_NAME_oneline(X509_get_subject_name(cert), NULL, 0)) != NULL) 240 ossl_cmp_log1(INFO, ctx, " subject = %s", str); 241 OPENSSL_free(str); 242 if (!self_issued) { 243 str = X509_NAME_oneline(X509_get_issuer_name(cert), NULL, 0); 244 if (str != NULL) 245 ossl_cmp_log1(INFO, ctx, " issuer = %s", str); 246 OPENSSL_free(str); 247 } 248 249 if (already_checked(cert, already_checked1) 250 || already_checked(cert, already_checked2)) { 251 ossl_cmp_info(ctx, " cert has already been checked"); 252 return 0; 253 } 254 255 time_cmp = X509_cmp_timeframe(vpm, X509_get0_notBefore(cert), 256 X509_get0_notAfter(cert)); 257 if (time_cmp != 0) { 258 ossl_cmp_warn(ctx, time_cmp > 0 ? "cert has expired" 259 : "cert is not yet valid"); 260 return 0; 261 } 262 263 if (!check_name(ctx, 1, 264 "cert subject", X509_get_subject_name(cert), 265 "sender field", msg->header->sender->d.directoryName)) 266 return 0; 267 268 if (!check_kid(ctx, X509_get0_subject_key_id(cert), msg->header->senderKID)) 269 return 0; 270 /* prevent misleading error later in case x509v3_cache_extensions() fails */ 271 if (!ossl_x509v3_cache_extensions(cert)) { 272 ossl_cmp_warn(ctx, "cert appears to be invalid"); 273 return 0; 274 } 275 if (!verify_signature(ctx, msg, cert)) { 276 ossl_cmp_warn(ctx, "msg signature verification failed"); 277 return 0; 278 } 279 /* acceptable also if there is no senderKID in msg header */ 280 ossl_cmp_info(ctx, " cert seems acceptable"); 281 return 1; 282} 283 284static int check_cert_path(const OSSL_CMP_CTX *ctx, X509_STORE *store, 285 X509 *scrt) 286{ 287 if (OSSL_CMP_validate_cert_path(ctx, store, scrt)) 288 return 1; 289 290 ossl_cmp_warn(ctx, 291 "msg signature validates but cert path validation failed"); 292 return 0; 293} 294 295/* 296 * Exceptional handling for 3GPP TS 33.310 [3G/LTE Network Domain Security 297 * (NDS); Authentication Framework (AF)], only to use for IP messages 298 * and if the ctx option is explicitly set: use self-issued certificates 299 * from extraCerts as trust anchor to validate sender cert - 300 * provided it also can validate the newly enrolled certificate 301 */ 302static int check_cert_path_3gpp(const OSSL_CMP_CTX *ctx, 303 const OSSL_CMP_MSG *msg, X509 *scrt) 304{ 305 int valid = 0; 306 X509_STORE *store; 307 308 if (!ctx->permitTAInExtraCertsForIR) 309 return 0; 310 311 if ((store = X509_STORE_new()) == NULL 312 || !ossl_cmp_X509_STORE_add1_certs(store, msg->extraCerts, 313 1 /* self-issued only */)) 314 goto err; 315 316 /* store does not include CRLs */ 317 valid = OSSL_CMP_validate_cert_path(ctx, store, scrt); 318 if (!valid) { 319 ossl_cmp_warn(ctx, 320 "also exceptional 3GPP mode cert path validation failed"); 321 } else { 322 /* 323 * verify that the newly enrolled certificate (which assumed rid == 324 * OSSL_CMP_CERTREQID) can also be validated with the same trusted store 325 */ 326 OSSL_CMP_CERTRESPONSE *crep = 327 ossl_cmp_certrepmessage_get0_certresponse(msg->body->value.ip, 328 OSSL_CMP_CERTREQID); 329 X509 *newcrt = ossl_cmp_certresponse_get1_cert(ctx, crep); 330 331 /* 332 * maybe better use get_cert_status() from cmp_client.c, which catches 333 * errors 334 */ 335 valid = OSSL_CMP_validate_cert_path(ctx, store, newcrt); 336 X509_free(newcrt); 337 } 338 339 err: 340 X509_STORE_free(store); 341 return valid; 342} 343 344static int check_msg_given_cert(const OSSL_CMP_CTX *ctx, X509 *cert, 345 const OSSL_CMP_MSG *msg) 346{ 347 return cert_acceptable(ctx, "previously validated", "sender cert", 348 cert, NULL, NULL, msg) 349 && (check_cert_path(ctx, ctx->trusted, cert) 350 || check_cert_path_3gpp(ctx, msg, cert)); 351} 352 353/*- 354 * Try all certs in given list for verifying msg, normally or in 3GPP mode. 355 * If already_checked1 == NULL then certs are assumed to be the msg->extraCerts. 356 * On success cache the found cert using ossl_cmp_ctx_set0_validatedSrvCert(). 357 */ 358static int check_msg_with_certs(OSSL_CMP_CTX *ctx, const STACK_OF(X509) *certs, 359 const char *desc, 360 const STACK_OF(X509) *already_checked1, 361 const STACK_OF(X509) *already_checked2, 362 const OSSL_CMP_MSG *msg, int mode_3gpp) 363{ 364 int in_extraCerts = already_checked1 == NULL; 365 int n_acceptable_certs = 0; 366 int i; 367 368 if (sk_X509_num(certs) <= 0) { 369 ossl_cmp_log1(WARN, ctx, "no %s", desc); 370 return 0; 371 } 372 373 for (i = 0; i < sk_X509_num(certs); i++) { /* certs may be NULL */ 374 X509 *cert = sk_X509_value(certs, i); 375 376 if (!ossl_assert(cert != NULL)) 377 return 0; 378 if (!cert_acceptable(ctx, "cert from", desc, cert, 379 already_checked1, already_checked2, msg)) 380 continue; 381 n_acceptable_certs++; 382 if (mode_3gpp ? check_cert_path_3gpp(ctx, msg, cert) 383 : check_cert_path(ctx, ctx->trusted, cert)) { 384 /* store successful sender cert for further msgs in transaction */ 385 if (!X509_up_ref(cert)) 386 return 0; 387 if (!ossl_cmp_ctx_set0_validatedSrvCert(ctx, cert)) { 388 X509_free(cert); 389 return 0; 390 } 391 return 1; 392 } 393 } 394 if (in_extraCerts && n_acceptable_certs == 0) 395 ossl_cmp_warn(ctx, "no acceptable cert in extraCerts"); 396 return 0; 397} 398 399/*- 400 * Verify msg trying first ctx->untrusted, which should include extraCerts 401 * at its front, then trying the trusted certs in truststore (if any) of ctx. 402 * On success cache the found cert using ossl_cmp_ctx_set0_validatedSrvCert(). 403 */ 404static int check_msg_all_certs(OSSL_CMP_CTX *ctx, const OSSL_CMP_MSG *msg, 405 int mode_3gpp) 406{ 407 int ret = 0; 408 409 if (mode_3gpp 410 && ((!ctx->permitTAInExtraCertsForIR 411 || OSSL_CMP_MSG_get_bodytype(msg) != OSSL_CMP_PKIBODY_IP))) 412 return 0; 413 414 ossl_cmp_info(ctx, 415 mode_3gpp ? "normal mode failed; trying now 3GPP mode trusting extraCerts" 416 : "trying first normal mode using trust store"); 417 if (check_msg_with_certs(ctx, msg->extraCerts, "extraCerts", 418 NULL, NULL, msg, mode_3gpp)) 419 return 1; 420 if (check_msg_with_certs(ctx, ctx->untrusted, "untrusted certs", 421 msg->extraCerts, NULL, msg, mode_3gpp)) 422 return 1; 423 424 if (ctx->trusted == NULL) { 425 ossl_cmp_warn(ctx, mode_3gpp ? "no self-issued extraCerts" 426 : "no trusted store"); 427 } else { 428 STACK_OF(X509) *trusted = X509_STORE_get1_all_certs(ctx->trusted); 429 ret = check_msg_with_certs(ctx, trusted, 430 mode_3gpp ? "self-issued extraCerts" 431 : "certs in trusted store", 432 msg->extraCerts, ctx->untrusted, 433 msg, mode_3gpp); 434 sk_X509_pop_free(trusted, X509_free); 435 } 436 return ret; 437} 438 439static int no_log_cb(const char *func, const char *file, int line, 440 OSSL_CMP_severity level, const char *msg) 441{ 442 return 1; 443} 444 445/*- 446 * Verify message signature with any acceptable and valid candidate cert. 447 * On success cache the found cert using ossl_cmp_ctx_set0_validatedSrvCert(). 448 */ 449static int check_msg_find_cert(OSSL_CMP_CTX *ctx, const OSSL_CMP_MSG *msg) 450{ 451 X509 *scrt = ctx->validatedSrvCert; /* previous successful sender cert */ 452 GENERAL_NAME *sender = msg->header->sender; 453 char *sname = NULL; 454 char *skid_str = NULL; 455 const ASN1_OCTET_STRING *skid = msg->header->senderKID; 456 OSSL_CMP_log_cb_t backup_log_cb = ctx->log_cb; 457 int res = 0; 458 459 if (sender == NULL || msg->body == NULL) 460 return 0; /* other NULL cases already have been checked */ 461 if (sender->type != GEN_DIRNAME) { 462 ERR_raise(ERR_LIB_CMP, CMP_R_SENDER_GENERALNAME_TYPE_NOT_SUPPORTED); 463 return 0; 464 } 465 466 /* dump any hitherto errors to avoid confusion when printing further ones */ 467 OSSL_CMP_CTX_print_errors(ctx); 468 469 /* enable clearing irrelevant errors in attempts to validate sender certs */ 470 (void)ERR_set_mark(); 471 ctx->log_cb = no_log_cb; /* temporarily disable logging */ 472 473 /* 474 * try first cached scrt, used successfully earlier in same transaction, 475 * for validating this and any further msgs where extraCerts may be left out 476 */ 477 if (scrt != NULL) { 478 if (check_msg_given_cert(ctx, scrt, msg)) { 479 ctx->log_cb = backup_log_cb; 480 (void)ERR_pop_to_mark(); 481 return 1; 482 } 483 /* cached sender cert has shown to be no more successfully usable */ 484 (void)ossl_cmp_ctx_set0_validatedSrvCert(ctx, NULL); 485 /* re-do the above check (just) for adding diagnostic information */ 486 ossl_cmp_info(ctx, 487 "trying to verify msg signature with previously validated cert"); 488 (void)check_msg_given_cert(ctx, scrt, msg); 489 } 490 491 res = check_msg_all_certs(ctx, msg, 0 /* using ctx->trusted */) 492 || check_msg_all_certs(ctx, msg, 1 /* 3gpp */); 493 ctx->log_cb = backup_log_cb; 494 if (res) { 495 /* discard any diagnostic information on trying to use certs */ 496 (void)ERR_pop_to_mark(); 497 goto end; 498 } 499 /* failed finding a sender cert that verifies the message signature */ 500 (void)ERR_clear_last_mark(); 501 502 sname = X509_NAME_oneline(sender->d.directoryName, NULL, 0); 503 skid_str = skid == NULL ? NULL 504 : OPENSSL_buf2hexstr(skid->data, skid->length); 505 if (ctx->log_cb != NULL) { 506 ossl_cmp_info(ctx, "trying to verify msg signature with a valid cert that.."); 507 if (sname != NULL) 508 ossl_cmp_log1(INFO, ctx, "matches msg sender = %s", sname); 509 if (skid_str != NULL) 510 ossl_cmp_log1(INFO, ctx, "matches msg senderKID = %s", skid_str); 511 else 512 ossl_cmp_info(ctx, "while msg header does not contain senderKID"); 513 /* re-do the above checks (just) for adding diagnostic information */ 514 (void)check_msg_all_certs(ctx, msg, 0 /* using ctx->trusted */); 515 (void)check_msg_all_certs(ctx, msg, 1 /* 3gpp */); 516 } 517 518 ERR_raise(ERR_LIB_CMP, CMP_R_NO_SUITABLE_SENDER_CERT); 519 if (sname != NULL) { 520 ERR_add_error_txt(NULL, "for msg sender name = "); 521 ERR_add_error_txt(NULL, sname); 522 } 523 if (skid_str != NULL) { 524 ERR_add_error_txt(" and ", "for msg senderKID = "); 525 ERR_add_error_txt(NULL, skid_str); 526 } 527 528 end: 529 OPENSSL_free(sname); 530 OPENSSL_free(skid_str); 531 return res; 532} 533 534/*- 535 * Validate the protection of the given PKIMessage using either password- 536 * based mac (PBM) or a signature algorithm. In the case of signature algorithm, 537 * the sender certificate can have been pinned by providing it in ctx->srvCert, 538 * else it is searched in msg->extraCerts, ctx->untrusted, in ctx->trusted 539 * (in this order) and is path is validated against ctx->trusted. 540 * On success cache the found cert using ossl_cmp_ctx_set0_validatedSrvCert(). 541 * 542 * If ctx->permitTAInExtraCertsForIR is true and when validating a CMP IP msg, 543 * the trust anchor for validating the IP msg may be taken from msg->extraCerts 544 * if a self-issued certificate is found there that can be used to 545 * validate the enrolled certificate returned in the IP. 546 * This is according to the need given in 3GPP TS 33.310. 547 * 548 * Returns 1 on success, 0 on error or validation failed. 549 */ 550int OSSL_CMP_validate_msg(OSSL_CMP_CTX *ctx, const OSSL_CMP_MSG *msg) 551{ 552 X509 *scrt; 553 554 ossl_cmp_debug(ctx, "validating CMP message"); 555 if (ctx == NULL || msg == NULL 556 || msg->header == NULL || msg->body == NULL) { 557 ERR_raise(ERR_LIB_CMP, CMP_R_NULL_ARGUMENT); 558 return 0; 559 } 560 561 if (msg->header->protectionAlg == NULL /* unprotected message */ 562 || msg->protection == NULL || msg->protection->data == NULL) { 563 ERR_raise(ERR_LIB_CMP, CMP_R_MISSING_PROTECTION); 564 return 0; 565 } 566 567 switch (ossl_cmp_hdr_get_protection_nid(msg->header)) { 568 /* 5.1.3.1. Shared Secret Information */ 569 case NID_id_PasswordBasedMAC: 570 if (ctx->secretValue == NULL) { 571 ossl_cmp_info(ctx, "no secret available for verifying PBM-based CMP message protection"); 572 ERR_raise(ERR_LIB_CMP, CMP_R_MISSING_SECRET); 573 return 0; 574 } 575 if (verify_PBMAC(ctx, msg)) { 576 /* 577 * RFC 4210, 5.3.2: 'Note that if the PKI Message Protection is 578 * "shared secret information", then any certificate transported in 579 * the caPubs field may be directly trusted as a root CA 580 * certificate by the initiator.' 581 */ 582 switch (OSSL_CMP_MSG_get_bodytype(msg)) { 583 case -1: 584 return 0; 585 case OSSL_CMP_PKIBODY_IP: 586 case OSSL_CMP_PKIBODY_CP: 587 case OSSL_CMP_PKIBODY_KUP: 588 case OSSL_CMP_PKIBODY_CCP: 589 if (ctx->trusted != NULL) { 590 STACK_OF(X509) *certs = msg->body->value.ip->caPubs; 591 /* value.ip is same for cp, kup, and ccp */ 592 593 if (!ossl_cmp_X509_STORE_add1_certs(ctx->trusted, certs, 0)) 594 /* adds both self-issued and not self-issued certs */ 595 return 0; 596 } 597 break; 598 default: 599 break; 600 } 601 ossl_cmp_debug(ctx, 602 "sucessfully validated PBM-based CMP message protection"); 603 return 1; 604 } 605 ossl_cmp_warn(ctx, "verifying PBM-based CMP message protection failed"); 606 break; 607 608 /* 609 * 5.1.3.2 DH Key Pairs 610 * Not yet supported 611 */ 612 case NID_id_DHBasedMac: 613 ERR_raise(ERR_LIB_CMP, CMP_R_UNSUPPORTED_PROTECTION_ALG_DHBASEDMAC); 614 break; 615 616 /* 617 * 5.1.3.3. Signature 618 */ 619 default: 620 scrt = ctx->srvCert; 621 if (scrt == NULL) { 622 if (ctx->trusted == NULL) { 623 ossl_cmp_info(ctx, "no trust store nor pinned server cert available for verifying signature-based CMP message protection"); 624 ERR_raise(ERR_LIB_CMP, CMP_R_MISSING_TRUST_ANCHOR); 625 return 0; 626 } 627 if (check_msg_find_cert(ctx, msg)) 628 return 1; 629 } else { /* use pinned sender cert */ 630 /* use ctx->srvCert for signature check even if not acceptable */ 631 if (verify_signature(ctx, msg, scrt)) { 632 ossl_cmp_debug(ctx, 633 "sucessfully validated signature-based CMP message protection"); 634 635 return 1; 636 } 637 ossl_cmp_warn(ctx, "CMP message signature verification failed"); 638 ERR_raise(ERR_LIB_CMP, CMP_R_SRVCERT_DOES_NOT_VALIDATE_MSG); 639 } 640 break; 641 } 642 return 0; 643} 644 645/*- 646 * Check received message (i.e., response by server or request from client) 647 * Any msg->extraCerts are prepended to ctx->untrusted. 648 * 649 * Ensures that: 650 * its sender is of appropriate type (curently only X509_NAME) and 651 * matches any expected sender or srvCert subject given in the ctx 652 * it has a valid body type 653 * its protection is valid (or invalid/absent, but only if a callback function 654 * is present and yields a positive result using also the supplied argument) 655 * its transaction ID matches the previous transaction ID stored in ctx (if any) 656 * its recipNonce matches the previous senderNonce stored in the ctx (if any) 657 * 658 * If everything is fine: 659 * learns the senderNonce from the received message, 660 * learns the transaction ID if it is not yet in ctx, 661 * and makes any certs in caPubs directly trusted. 662 * 663 * Returns 1 on success, 0 on error. 664 */ 665int ossl_cmp_msg_check_update(OSSL_CMP_CTX *ctx, const OSSL_CMP_MSG *msg, 666 ossl_cmp_allow_unprotected_cb_t cb, int cb_arg) 667{ 668 OSSL_CMP_PKIHEADER *hdr; 669 const X509_NAME *expected_sender; 670 671 if (!ossl_assert(ctx != NULL && msg != NULL && msg->header != NULL)) 672 return 0; 673 hdr = OSSL_CMP_MSG_get0_header(msg); 674 675 /* validate sender name of received msg */ 676 if (hdr->sender->type != GEN_DIRNAME) { 677 ERR_raise(ERR_LIB_CMP, CMP_R_SENDER_GENERALNAME_TYPE_NOT_SUPPORTED); 678 return 0; 679 } 680 /* 681 * Compare actual sender name of response with expected sender name. 682 * Mitigates risk to accept misused PBM secret 683 * or misused certificate of an unauthorized entity of a trusted hierarchy. 684 */ 685 expected_sender = ctx->expected_sender; 686 if (expected_sender == NULL && ctx->srvCert != NULL) 687 expected_sender = X509_get_subject_name(ctx->srvCert); 688 if (!check_name(ctx, 0, "sender DN field", hdr->sender->d.directoryName, 689 "expected sender", expected_sender)) 690 return 0; 691 /* Note: if recipient was NULL-DN it could be learned here if needed */ 692 693 if (sk_X509_num(msg->extraCerts) > 10) 694 ossl_cmp_warn(ctx, 695 "received CMP message contains more than 10 extraCerts"); 696 /* 697 * Store any provided extraCerts in ctx for use in OSSL_CMP_validate_msg() 698 * and for future use, such that they are available to ctx->certConf_cb and 699 * the peer does not need to send them again in the same transaction. 700 * Note that it does not help validating the message before storing the 701 * extraCerts because they do not belong to the protected msg part anyway. 702 * For efficiency, the extraCerts are prepended so they get used first. 703 */ 704 if (!X509_add_certs(ctx->untrusted, msg->extraCerts, 705 /* this allows self-signed certs */ 706 X509_ADD_FLAG_UP_REF | X509_ADD_FLAG_NO_DUP 707 | X509_ADD_FLAG_PREPEND)) 708 return 0; 709 710 /* validate message protection */ 711 if (hdr->protectionAlg != NULL) { 712 /* detect explicitly permitted exceptions for invalid protection */ 713 if (!OSSL_CMP_validate_msg(ctx, msg) 714 && (cb == NULL || (*cb)(ctx, msg, 1, cb_arg) <= 0)) { 715#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION 716 ERR_raise(ERR_LIB_CMP, CMP_R_ERROR_VALIDATING_PROTECTION); 717 return 0; 718#endif 719 } 720 } else { 721 /* detect explicitly permitted exceptions for missing protection */ 722 if (cb == NULL || (*cb)(ctx, msg, 0, cb_arg) <= 0) { 723#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION 724 ERR_raise(ERR_LIB_CMP, CMP_R_MISSING_PROTECTION); 725 return 0; 726#endif 727 } 728 } 729 730 /* check CMP version number in header */ 731 if (ossl_cmp_hdr_get_pvno(hdr) != OSSL_CMP_PVNO) { 732#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION 733 ERR_raise(ERR_LIB_CMP, CMP_R_UNEXPECTED_PVNO); 734 return 0; 735#endif 736 } 737 738 if (OSSL_CMP_MSG_get_bodytype(msg) < 0) { 739#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION 740 ERR_raise(ERR_LIB_CMP, CMP_R_PKIBODY_ERROR); 741 return 0; 742#endif 743 } 744 745 /* compare received transactionID with the expected one in previous msg */ 746 if (ctx->transactionID != NULL 747 && (hdr->transactionID == NULL 748 || ASN1_OCTET_STRING_cmp(ctx->transactionID, 749 hdr->transactionID) != 0)) { 750#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION 751 ERR_raise(ERR_LIB_CMP, CMP_R_TRANSACTIONID_UNMATCHED); 752 return 0; 753#endif 754 } 755 756 /* compare received nonce with the one we sent */ 757 if (ctx->senderNonce != NULL 758 && (msg->header->recipNonce == NULL 759 || ASN1_OCTET_STRING_cmp(ctx->senderNonce, 760 hdr->recipNonce) != 0)) { 761#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION 762 ERR_raise(ERR_LIB_CMP, CMP_R_RECIPNONCE_UNMATCHED); 763 return 0; 764#endif 765 } 766 767 /* if not yet present, learn transactionID */ 768 if (ctx->transactionID == NULL 769 && !OSSL_CMP_CTX_set1_transactionID(ctx, hdr->transactionID)) 770 return 0; 771 772 /* 773 * RFC 4210 section 5.1.1 states: the recipNonce is copied from 774 * the senderNonce of the previous message in the transaction. 775 * --> Store for setting in next message 776 */ 777 if (!ossl_cmp_ctx_set1_recipNonce(ctx, hdr->senderNonce)) 778 return 0; 779 780 /* 781 * Store any provided extraCerts in ctx for future use, 782 * such that they are available to ctx->certConf_cb and 783 * the peer does not need to send them again in the same transaction. 784 * For efficiency, the extraCerts are prepended so they get used first. 785 */ 786 if (!X509_add_certs(ctx->untrusted, msg->extraCerts, 787 /* this allows self-signed certs */ 788 X509_ADD_FLAG_UP_REF | X509_ADD_FLAG_NO_DUP 789 | X509_ADD_FLAG_PREPEND)) 790 return 0; 791 792 if (ossl_cmp_hdr_get_protection_nid(hdr) == NID_id_PasswordBasedMAC) { 793 /* 794 * RFC 4210, 5.3.2: 'Note that if the PKI Message Protection is 795 * "shared secret information", then any certificate transported in 796 * the caPubs field may be directly trusted as a root CA 797 * certificate by the initiator.' 798 */ 799 switch (OSSL_CMP_MSG_get_bodytype(msg)) { 800 case OSSL_CMP_PKIBODY_IP: 801 case OSSL_CMP_PKIBODY_CP: 802 case OSSL_CMP_PKIBODY_KUP: 803 case OSSL_CMP_PKIBODY_CCP: 804 if (ctx->trusted != NULL) { 805 STACK_OF(X509) *certs = msg->body->value.ip->caPubs; 806 /* value.ip is same for cp, kup, and ccp */ 807 808 if (!ossl_cmp_X509_STORE_add1_certs(ctx->trusted, certs, 0)) 809 /* adds both self-issued and not self-issued certs */ 810 return 0; 811 } 812 break; 813 default: 814 break; 815 } 816 } 817 return 1; 818} 819 820int ossl_cmp_verify_popo(const OSSL_CMP_CTX *ctx, 821 const OSSL_CMP_MSG *msg, int acceptRAVerified) 822{ 823 if (!ossl_assert(msg != NULL && msg->body != NULL)) 824 return 0; 825 switch (msg->body->type) { 826 case OSSL_CMP_PKIBODY_P10CR: 827 { 828 X509_REQ *req = msg->body->value.p10cr; 829 830 if (X509_REQ_verify_ex(req, X509_REQ_get0_pubkey(req), ctx->libctx, 831 ctx->propq) <= 0) { 832#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION 833 ERR_raise(ERR_LIB_CMP, CMP_R_REQUEST_NOT_ACCEPTED); 834 return 0; 835#endif 836 } 837 } 838 break; 839 case OSSL_CMP_PKIBODY_IR: 840 case OSSL_CMP_PKIBODY_CR: 841 case OSSL_CMP_PKIBODY_KUR: 842 if (!OSSL_CRMF_MSGS_verify_popo(msg->body->value.ir, OSSL_CMP_CERTREQID, 843 acceptRAVerified, 844 ctx->libctx, ctx->propq)) { 845#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION 846 return 0; 847#endif 848 } 849 break; 850 default: 851 ERR_raise(ERR_LIB_CMP, CMP_R_PKIBODY_ERROR); 852 return 0; 853 } 854 return 1; 855} 856