1 /* 2 * validator/validator.c - secure validator DNS query response module 3 * 4 * Copyright (c) 2007, NLnet Labs. All rights reserved. 5 * 6 * This software is open source. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * Redistributions of source code must retain the above copyright notice, 13 * this list of conditions and the following disclaimer. 14 * 15 * Redistributions in binary form must reproduce the above copyright notice, 16 * this list of conditions and the following disclaimer in the documentation 17 * and/or other materials provided with the distribution. 18 * 19 * Neither the name of the NLNET LABS nor the names of its contributors may 20 * be used to endorse or promote products derived from this software without 21 * specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 27 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36 /** 37 * \file 38 * 39 * This file contains a module that performs validation of DNS queries. 40 * According to RFC 4034. 41 */ 42 #include "config.h" 43 #include "validator/validator.h" 44 #include "validator/val_anchor.h" 45 #include "validator/val_kcache.h" 46 #include "validator/val_kentry.h" 47 #include "validator/val_utils.h" 48 #include "validator/val_nsec.h" 49 #include "validator/val_nsec3.h" 50 #include "validator/val_neg.h" 51 #include "validator/val_sigcrypt.h" 52 #include "validator/autotrust.h" 53 #include "services/cache/dns.h" 54 #include "util/data/dname.h" 55 #include "util/module.h" 56 #include "util/log.h" 57 #include "util/net_help.h" 58 #include "util/regional.h" 59 #include "util/config_file.h" 60 #include "util/fptr_wlist.h" 61 #include "ldns/rrdef.h" 62 #include "ldns/wire2str.h" 63 64 /* forward decl for cache response and normal super inform calls of a DS */ 65 static void process_ds_response(struct module_qstate* qstate, 66 struct val_qstate* vq, int id, int rcode, struct dns_msg* msg, 67 struct query_info* qinfo, struct sock_list* origin); 68 69 /** fill up nsec3 key iterations config entry */ 70 static int 71 fill_nsec3_iter(struct val_env* ve, char* s, int c) 72 { 73 char* e; 74 int i; 75 free(ve->nsec3_keysize); 76 free(ve->nsec3_maxiter); 77 ve->nsec3_keysize = (size_t*)calloc(sizeof(size_t), (size_t)c); 78 ve->nsec3_maxiter = (size_t*)calloc(sizeof(size_t), (size_t)c); 79 if(!ve->nsec3_keysize || !ve->nsec3_maxiter) { 80 log_err("out of memory"); 81 return 0; 82 } 83 for(i=0; i<c; i++) { 84 ve->nsec3_keysize[i] = (size_t)strtol(s, &e, 10); 85 if(s == e) { 86 log_err("cannot parse: %s", s); 87 return 0; 88 } 89 s = e; 90 ve->nsec3_maxiter[i] = (size_t)strtol(s, &e, 10); 91 if(s == e) { 92 log_err("cannot parse: %s", s); 93 return 0; 94 } 95 s = e; 96 if(i>0 && ve->nsec3_keysize[i-1] >= ve->nsec3_keysize[i]) { 97 log_err("nsec3 key iterations not ascending: %d %d", 98 (int)ve->nsec3_keysize[i-1], 99 (int)ve->nsec3_keysize[i]); 100 return 0; 101 } 102 verbose(VERB_ALGO, "validator nsec3cfg keysz %d mxiter %d", 103 (int)ve->nsec3_keysize[i], (int)ve->nsec3_maxiter[i]); 104 } 105 return 1; 106 } 107 108 /** apply config settings to validator */ 109 static int 110 val_apply_cfg(struct module_env* env, struct val_env* val_env, 111 struct config_file* cfg) 112 { 113 int c; 114 val_env->bogus_ttl = (uint32_t)cfg->bogus_ttl; 115 val_env->clean_additional = cfg->val_clean_additional; 116 val_env->permissive_mode = cfg->val_permissive_mode; 117 if(!env->anchors) 118 env->anchors = anchors_create(); 119 if(!env->anchors) { 120 log_err("out of memory"); 121 return 0; 122 } 123 if(!val_env->kcache) 124 val_env->kcache = key_cache_create(cfg); 125 if(!val_env->kcache) { 126 log_err("out of memory"); 127 return 0; 128 } 129 env->key_cache = val_env->kcache; 130 if(!anchors_apply_cfg(env->anchors, cfg)) { 131 log_err("validator: error in trustanchors config"); 132 return 0; 133 } 134 val_env->date_override = cfg->val_date_override; 135 val_env->skew_min = cfg->val_sig_skew_min; 136 val_env->skew_max = cfg->val_sig_skew_max; 137 c = cfg_count_numbers(cfg->val_nsec3_key_iterations); 138 if(c < 1 || (c&1)) { 139 log_err("validator: unparseable or odd nsec3 key " 140 "iterations: %s", cfg->val_nsec3_key_iterations); 141 return 0; 142 } 143 val_env->nsec3_keyiter_count = c/2; 144 if(!fill_nsec3_iter(val_env, cfg->val_nsec3_key_iterations, c/2)) { 145 log_err("validator: cannot apply nsec3 key iterations"); 146 return 0; 147 } 148 if(!val_env->neg_cache) 149 val_env->neg_cache = val_neg_create(cfg, 150 val_env->nsec3_maxiter[val_env->nsec3_keyiter_count-1]); 151 if(!val_env->neg_cache) { 152 log_err("out of memory"); 153 return 0; 154 } 155 env->neg_cache = val_env->neg_cache; 156 return 1; 157 } 158 159 int 160 val_init(struct module_env* env, int id) 161 { 162 struct val_env* val_env = (struct val_env*)calloc(1, 163 sizeof(struct val_env)); 164 if(!val_env) { 165 log_err("malloc failure"); 166 return 0; 167 } 168 env->modinfo[id] = (void*)val_env; 169 env->need_to_validate = 1; 170 val_env->permissive_mode = 0; 171 lock_basic_init(&val_env->bogus_lock); 172 lock_protect(&val_env->bogus_lock, &val_env->num_rrset_bogus, 173 sizeof(val_env->num_rrset_bogus)); 174 if(!val_apply_cfg(env, val_env, env->cfg)) { 175 log_err("validator: could not apply configuration settings."); 176 return 0; 177 } 178 return 1; 179 } 180 181 void 182 val_deinit(struct module_env* env, int id) 183 { 184 struct val_env* val_env; 185 if(!env || !env->modinfo[id]) 186 return; 187 val_env = (struct val_env*)env->modinfo[id]; 188 lock_basic_destroy(&val_env->bogus_lock); 189 anchors_delete(env->anchors); 190 env->anchors = NULL; 191 key_cache_delete(val_env->kcache); 192 neg_cache_delete(val_env->neg_cache); 193 free(val_env->nsec3_keysize); 194 free(val_env->nsec3_maxiter); 195 free(val_env); 196 env->modinfo[id] = NULL; 197 } 198 199 /** fill in message structure */ 200 static struct val_qstate* 201 val_new_getmsg(struct module_qstate* qstate, struct val_qstate* vq) 202 { 203 if(!qstate->return_msg || qstate->return_rcode != LDNS_RCODE_NOERROR) { 204 /* create a message to verify */ 205 verbose(VERB_ALGO, "constructing reply for validation"); 206 vq->orig_msg = (struct dns_msg*)regional_alloc(qstate->region, 207 sizeof(struct dns_msg)); 208 if(!vq->orig_msg) 209 return NULL; 210 vq->orig_msg->qinfo = qstate->qinfo; 211 vq->orig_msg->rep = (struct reply_info*)regional_alloc( 212 qstate->region, sizeof(struct reply_info)); 213 if(!vq->orig_msg->rep) 214 return NULL; 215 memset(vq->orig_msg->rep, 0, sizeof(struct reply_info)); 216 vq->orig_msg->rep->flags = (uint16_t)(qstate->return_rcode&0xf) 217 |BIT_QR|BIT_RA|(qstate->query_flags|(BIT_CD|BIT_RD)); 218 vq->orig_msg->rep->qdcount = 1; 219 } else { 220 vq->orig_msg = qstate->return_msg; 221 } 222 vq->qchase = qstate->qinfo; 223 /* chase reply will be an edited (sub)set of the orig msg rrset ptrs */ 224 vq->chase_reply = regional_alloc_init(qstate->region, 225 vq->orig_msg->rep, 226 sizeof(struct reply_info) - sizeof(struct rrset_ref)); 227 if(!vq->chase_reply) 228 return NULL; 229 vq->chase_reply->rrsets = regional_alloc_init(qstate->region, 230 vq->orig_msg->rep->rrsets, sizeof(struct ub_packed_rrset_key*) 231 * vq->orig_msg->rep->rrset_count); 232 if(!vq->chase_reply->rrsets) 233 return NULL; 234 vq->rrset_skip = 0; 235 return vq; 236 } 237 238 /** allocate new validator query state */ 239 static struct val_qstate* 240 val_new(struct module_qstate* qstate, int id) 241 { 242 struct val_qstate* vq = (struct val_qstate*)regional_alloc( 243 qstate->region, sizeof(*vq)); 244 log_assert(!qstate->minfo[id]); 245 if(!vq) 246 return NULL; 247 memset(vq, 0, sizeof(*vq)); 248 qstate->minfo[id] = vq; 249 vq->state = VAL_INIT_STATE; 250 return val_new_getmsg(qstate, vq); 251 } 252 253 /** 254 * Exit validation with an error status 255 * 256 * @param qstate: query state 257 * @param id: validator id. 258 * @return false, for use by caller to return to stop processing. 259 */ 260 static int 261 val_error(struct module_qstate* qstate, int id) 262 { 263 qstate->ext_state[id] = module_error; 264 qstate->return_rcode = LDNS_RCODE_SERVFAIL; 265 return 0; 266 } 267 268 /** 269 * Check to see if a given response needs to go through the validation 270 * process. Typical reasons for this routine to return false are: CD bit was 271 * on in the original request, or the response is a kind of message that 272 * is unvalidatable (i.e., SERVFAIL, REFUSED, etc.) 273 * 274 * @param qstate: query state. 275 * @param ret_rc: rcode for this message (if noerror - examine ret_msg). 276 * @param ret_msg: return msg, can be NULL; look at rcode instead. 277 * @return true if the response could use validation (although this does not 278 * mean we can actually validate this response). 279 */ 280 static int 281 needs_validation(struct module_qstate* qstate, int ret_rc, 282 struct dns_msg* ret_msg) 283 { 284 int rcode; 285 286 /* If the CD bit is on in the original request, then you could think 287 * that we don't bother to validate anything. 288 * But this is signalled internally with the valrec flag. 289 * User queries are validated with BIT_CD to make our cache clean 290 * so that bogus messages get retried by the upstream also for 291 * downstream validators that set BIT_CD. 292 * For DNS64 bit_cd signals no dns64 processing, but we want to 293 * provide validation there too */ 294 /* 295 if(qstate->query_flags & BIT_CD) { 296 verbose(VERB_ALGO, "not validating response due to CD bit"); 297 return 0; 298 } 299 */ 300 if(qstate->is_valrec) { 301 verbose(VERB_ALGO, "not validating response, is valrec" 302 "(validation recursion lookup)"); 303 return 0; 304 } 305 306 if(ret_rc != LDNS_RCODE_NOERROR || !ret_msg) 307 rcode = ret_rc; 308 else rcode = (int)FLAGS_GET_RCODE(ret_msg->rep->flags); 309 310 if(rcode != LDNS_RCODE_NOERROR && rcode != LDNS_RCODE_NXDOMAIN) { 311 if(verbosity >= VERB_ALGO) { 312 char rc[16]; 313 rc[0]=0; 314 (void)sldns_wire2str_rcode_buf(rcode, rc, sizeof(rc)); 315 verbose(VERB_ALGO, "cannot validate non-answer, rcode %s", rc); 316 } 317 return 0; 318 } 319 320 /* cannot validate positive RRSIG response. (negatives can) */ 321 if(qstate->qinfo.qtype == LDNS_RR_TYPE_RRSIG && 322 rcode == LDNS_RCODE_NOERROR && ret_msg && 323 ret_msg->rep->an_numrrsets > 0) { 324 verbose(VERB_ALGO, "cannot validate RRSIG, no sigs on sigs."); 325 return 0; 326 } 327 return 1; 328 } 329 330 /** 331 * Check to see if the response has already been validated. 332 * @param ret_msg: return msg, can be NULL 333 * @return true if the response has already been validated 334 */ 335 static int 336 already_validated(struct dns_msg* ret_msg) 337 { 338 /* validate unchecked, and re-validate bogus messages */ 339 if (ret_msg && ret_msg->rep->security > sec_status_bogus) 340 { 341 verbose(VERB_ALGO, "response has already been validated: %s", 342 sec_status_to_string(ret_msg->rep->security)); 343 return 1; 344 } 345 return 0; 346 } 347 348 /** 349 * Generate a request for DNS data. 350 * 351 * @param qstate: query state that is the parent. 352 * @param id: module id. 353 * @param name: what name to query for. 354 * @param namelen: length of name. 355 * @param qtype: query type. 356 * @param qclass: query class. 357 * @param flags: additional flags, such as the CD bit (BIT_CD), or 0. 358 * @return false on alloc failure. 359 */ 360 static int 361 generate_request(struct module_qstate* qstate, int id, uint8_t* name, 362 size_t namelen, uint16_t qtype, uint16_t qclass, uint16_t flags) 363 { 364 struct val_qstate* vq = (struct val_qstate*)qstate->minfo[id]; 365 struct module_qstate* newq; 366 struct query_info ask; 367 int valrec; 368 ask.qname = name; 369 ask.qname_len = namelen; 370 ask.qtype = qtype; 371 ask.qclass = qclass; 372 log_query_info(VERB_ALGO, "generate request", &ask); 373 fptr_ok(fptr_whitelist_modenv_attach_sub(qstate->env->attach_sub)); 374 /* enable valrec flag to avoid recursion to the same validation 375 * routine, this lookup is simply a lookup. DLVs need validation */ 376 if(qtype == LDNS_RR_TYPE_DLV) 377 valrec = 0; 378 else valrec = 1; 379 if(!(*qstate->env->attach_sub)(qstate, &ask, 380 (uint16_t)(BIT_RD|flags), 0, valrec, &newq)){ 381 log_err("Could not generate request: out of memory"); 382 return 0; 383 } 384 /* newq; validator does not need state created for that 385 * query, and its a 'normal' for iterator as well */ 386 if(newq) { 387 /* add our blacklist to the query blacklist */ 388 sock_list_merge(&newq->blacklist, newq->region, 389 vq->chain_blacklist); 390 } 391 qstate->ext_state[id] = module_wait_subquery; 392 return 1; 393 } 394 395 /** 396 * Prime trust anchor for use. 397 * Generate and dispatch a priming query for the given trust anchor. 398 * The trust anchor can be DNSKEY or DS and does not have to be signed. 399 * 400 * @param qstate: query state. 401 * @param vq: validator query state. 402 * @param id: module id. 403 * @param toprime: what to prime. 404 * @return false on a processing error. 405 */ 406 static int 407 prime_trust_anchor(struct module_qstate* qstate, struct val_qstate* vq, 408 int id, struct trust_anchor* toprime) 409 { 410 int ret = generate_request(qstate, id, toprime->name, toprime->namelen, 411 LDNS_RR_TYPE_DNSKEY, toprime->dclass, BIT_CD); 412 if(!ret) { 413 log_err("Could not prime trust anchor: out of memory"); 414 return 0; 415 } 416 /* ignore newq; validator does not need state created for that 417 * query, and its a 'normal' for iterator as well */ 418 vq->wait_prime_ta = 1; /* to elicit PRIME_RESP_STATE processing 419 from the validator inform_super() routine */ 420 /* store trust anchor name for later lookup when prime returns */ 421 vq->trust_anchor_name = regional_alloc_init(qstate->region, 422 toprime->name, toprime->namelen); 423 vq->trust_anchor_len = toprime->namelen; 424 vq->trust_anchor_labs = toprime->namelabs; 425 if(!vq->trust_anchor_name) { 426 log_err("Could not prime trust anchor: out of memory"); 427 return 0; 428 } 429 return 1; 430 } 431 432 /** 433 * Validate if the ANSWER and AUTHORITY sections contain valid rrsets. 434 * They must be validly signed with the given key. 435 * Tries to validate ADDITIONAL rrsets as well, but only to check them. 436 * Allows unsigned CNAME after a DNAME that expands the DNAME. 437 * 438 * Note that by the time this method is called, the process of finding the 439 * trusted DNSKEY rrset that signs this response must already have been 440 * completed. 441 * 442 * @param qstate: query state. 443 * @param env: module env for verify. 444 * @param ve: validator env for verify. 445 * @param qchase: query that was made. 446 * @param chase_reply: answer to validate. 447 * @param key_entry: the key entry, which is trusted, and which matches 448 * the signer of the answer. The key entry isgood(). 449 * @return false if any of the rrsets in the an or ns sections of the message 450 * fail to verify. The message is then set to bogus. 451 */ 452 static int 453 validate_msg_signatures(struct module_qstate* qstate, struct module_env* env, 454 struct val_env* ve, struct query_info* qchase, 455 struct reply_info* chase_reply, struct key_entry_key* key_entry) 456 { 457 uint8_t* sname; 458 size_t i, slen; 459 struct ub_packed_rrset_key* s; 460 enum sec_status sec; 461 int dname_seen = 0; 462 char* reason = NULL; 463 464 /* validate the ANSWER section */ 465 for(i=0; i<chase_reply->an_numrrsets; i++) { 466 s = chase_reply->rrsets[i]; 467 /* Skip the CNAME following a (validated) DNAME. 468 * Because of the normalization routines in the iterator, 469 * there will always be an unsigned CNAME following a DNAME 470 * (unless qtype=DNAME). */ 471 if(dname_seen && ntohs(s->rk.type) == LDNS_RR_TYPE_CNAME) { 472 dname_seen = 0; 473 /* CNAME was synthesized by our own iterator */ 474 /* since the DNAME verified, mark the CNAME as secure */ 475 ((struct packed_rrset_data*)s->entry.data)->security = 476 sec_status_secure; 477 ((struct packed_rrset_data*)s->entry.data)->trust = 478 rrset_trust_validated; 479 continue; 480 } 481 482 /* Verify the answer rrset */ 483 sec = val_verify_rrset_entry(env, ve, s, key_entry, &reason); 484 /* If the (answer) rrset failed to validate, then this 485 * message is BAD. */ 486 if(sec != sec_status_secure) { 487 log_nametypeclass(VERB_QUERY, "validator: response " 488 "has failed ANSWER rrset:", s->rk.dname, 489 ntohs(s->rk.type), ntohs(s->rk.rrset_class)); 490 errinf(qstate, reason); 491 if(ntohs(s->rk.type) == LDNS_RR_TYPE_CNAME) 492 errinf(qstate, "for CNAME"); 493 else if(ntohs(s->rk.type) == LDNS_RR_TYPE_DNAME) 494 errinf(qstate, "for DNAME"); 495 errinf_origin(qstate, qstate->reply_origin); 496 chase_reply->security = sec_status_bogus; 497 return 0; 498 } 499 500 /* Notice a DNAME that should be followed by an unsigned 501 * CNAME. */ 502 if(qchase->qtype != LDNS_RR_TYPE_DNAME && 503 ntohs(s->rk.type) == LDNS_RR_TYPE_DNAME) { 504 dname_seen = 1; 505 } 506 } 507 508 /* validate the AUTHORITY section */ 509 for(i=chase_reply->an_numrrsets; i<chase_reply->an_numrrsets+ 510 chase_reply->ns_numrrsets; i++) { 511 s = chase_reply->rrsets[i]; 512 sec = val_verify_rrset_entry(env, ve, s, key_entry, &reason); 513 /* If anything in the authority section fails to be secure, 514 * we have a bad message. */ 515 if(sec != sec_status_secure) { 516 log_nametypeclass(VERB_QUERY, "validator: response " 517 "has failed AUTHORITY rrset:", s->rk.dname, 518 ntohs(s->rk.type), ntohs(s->rk.rrset_class)); 519 errinf(qstate, reason); 520 errinf_rrset(qstate, s); 521 errinf_origin(qstate, qstate->reply_origin); 522 chase_reply->security = sec_status_bogus; 523 return 0; 524 } 525 } 526 527 /* attempt to validate the ADDITIONAL section rrsets */ 528 if(!ve->clean_additional) 529 return 1; 530 for(i=chase_reply->an_numrrsets+chase_reply->ns_numrrsets; 531 i<chase_reply->rrset_count; i++) { 532 s = chase_reply->rrsets[i]; 533 /* only validate rrs that have signatures with the key */ 534 /* leave others unchecked, those get removed later on too */ 535 val_find_rrset_signer(s, &sname, &slen); 536 if(sname && query_dname_compare(sname, key_entry->name)==0) 537 (void)val_verify_rrset_entry(env, ve, s, key_entry, 538 &reason); 539 /* the additional section can fail to be secure, 540 * it is optional, check signature in case we need 541 * to clean the additional section later. */ 542 } 543 544 return 1; 545 } 546 547 /** 548 * Detect wrong truncated response (say from BIND 9.6.1 that is forwarding 549 * and saw the NS record without signatures from a referral). 550 * The positive response has a mangled authority section. 551 * Remove that authority section and the additional section. 552 * @param rep: reply 553 * @return true if a wrongly truncated response. 554 */ 555 static int 556 detect_wrongly_truncated(struct reply_info* rep) 557 { 558 size_t i; 559 /* only NS in authority, and it is bogus */ 560 if(rep->ns_numrrsets != 1 || rep->an_numrrsets == 0) 561 return 0; 562 if(ntohs(rep->rrsets[ rep->an_numrrsets ]->rk.type) != LDNS_RR_TYPE_NS) 563 return 0; 564 if(((struct packed_rrset_data*)rep->rrsets[ rep->an_numrrsets ] 565 ->entry.data)->security == sec_status_secure) 566 return 0; 567 /* answer section is present and secure */ 568 for(i=0; i<rep->an_numrrsets; i++) { 569 if(((struct packed_rrset_data*)rep->rrsets[ i ] 570 ->entry.data)->security != sec_status_secure) 571 return 0; 572 } 573 verbose(VERB_ALGO, "truncating to minimal response"); 574 return 1; 575 } 576 577 578 /** 579 * Given a "positive" response -- a response that contains an answer to the 580 * question, and no CNAME chain, validate this response. 581 * 582 * The answer and authority RRsets must already be verified as secure. 583 * 584 * @param env: module env for verify. 585 * @param ve: validator env for verify. 586 * @param qchase: query that was made. 587 * @param chase_reply: answer to that query to validate. 588 * @param kkey: the key entry, which is trusted, and which matches 589 * the signer of the answer. The key entry isgood(). 590 */ 591 static void 592 validate_positive_response(struct module_env* env, struct val_env* ve, 593 struct query_info* qchase, struct reply_info* chase_reply, 594 struct key_entry_key* kkey) 595 { 596 uint8_t* wc = NULL; 597 int wc_NSEC_ok = 0; 598 int nsec3s_seen = 0; 599 size_t i; 600 struct ub_packed_rrset_key* s; 601 602 /* validate the ANSWER section - this will be the answer itself */ 603 for(i=0; i<chase_reply->an_numrrsets; i++) { 604 s = chase_reply->rrsets[i]; 605 606 /* Check to see if the rrset is the result of a wildcard 607 * expansion. If so, an additional check will need to be 608 * made in the authority section. */ 609 if(!val_rrset_wildcard(s, &wc)) { 610 log_nametypeclass(VERB_QUERY, "Positive response has " 611 "inconsistent wildcard sigs:", s->rk.dname, 612 ntohs(s->rk.type), ntohs(s->rk.rrset_class)); 613 chase_reply->security = sec_status_bogus; 614 return; 615 } 616 } 617 618 /* validate the AUTHORITY section as well - this will generally be 619 * the NS rrset (which could be missing, no problem) */ 620 for(i=chase_reply->an_numrrsets; i<chase_reply->an_numrrsets+ 621 chase_reply->ns_numrrsets; i++) { 622 s = chase_reply->rrsets[i]; 623 624 /* If this is a positive wildcard response, and we have a 625 * (just verified) NSEC record, try to use it to 1) prove 626 * that qname doesn't exist and 2) that the correct wildcard 627 * was used. */ 628 if(wc != NULL && ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC) { 629 if(val_nsec_proves_positive_wildcard(s, qchase, wc)) { 630 wc_NSEC_ok = 1; 631 } 632 /* if not, continue looking for proof */ 633 } 634 635 /* Otherwise, if this is a positive wildcard response and 636 * we have NSEC3 records */ 637 if(wc != NULL && ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC3) { 638 nsec3s_seen = 1; 639 } 640 } 641 642 /* If this was a positive wildcard response that we haven't already 643 * proven, and we have NSEC3 records, try to prove it using the NSEC3 644 * records. */ 645 if(wc != NULL && !wc_NSEC_ok && nsec3s_seen) { 646 enum sec_status sec = nsec3_prove_wildcard(env, ve, 647 chase_reply->rrsets+chase_reply->an_numrrsets, 648 chase_reply->ns_numrrsets, qchase, kkey, wc); 649 if(sec == sec_status_insecure) { 650 verbose(VERB_ALGO, "Positive wildcard response is " 651 "insecure"); 652 chase_reply->security = sec_status_insecure; 653 return; 654 } else if(sec == sec_status_secure) 655 wc_NSEC_ok = 1; 656 } 657 658 /* If after all this, we still haven't proven the positive wildcard 659 * response, fail. */ 660 if(wc != NULL && !wc_NSEC_ok) { 661 verbose(VERB_QUERY, "positive response was wildcard " 662 "expansion and did not prove original data " 663 "did not exist"); 664 chase_reply->security = sec_status_bogus; 665 return; 666 } 667 668 verbose(VERB_ALGO, "Successfully validated positive response"); 669 chase_reply->security = sec_status_secure; 670 } 671 672 /** 673 * Validate a NOERROR/NODATA signed response -- a response that has a 674 * NOERROR Rcode but no ANSWER section RRsets. This consists of making 675 * certain that the authority section NSEC/NSEC3s proves that the qname 676 * does exist and the qtype doesn't. 677 * 678 * The answer and authority RRsets must already be verified as secure. 679 * 680 * @param env: module env for verify. 681 * @param ve: validator env for verify. 682 * @param qchase: query that was made. 683 * @param chase_reply: answer to that query to validate. 684 * @param kkey: the key entry, which is trusted, and which matches 685 * the signer of the answer. The key entry isgood(). 686 */ 687 static void 688 validate_nodata_response(struct module_env* env, struct val_env* ve, 689 struct query_info* qchase, struct reply_info* chase_reply, 690 struct key_entry_key* kkey) 691 { 692 /* Since we are here, there must be nothing in the ANSWER section to 693 * validate. */ 694 /* (Note: CNAME/DNAME responses will not directly get here -- 695 * instead, they are chased down into indiviual CNAME validations, 696 * and at the end of the cname chain a POSITIVE, or CNAME_NOANSWER 697 * validation.) */ 698 699 /* validate the AUTHORITY section */ 700 int has_valid_nsec = 0; /* If true, then the NODATA has been proven.*/ 701 uint8_t* ce = NULL; /* for wildcard nodata responses. This is the 702 proven closest encloser. */ 703 uint8_t* wc = NULL; /* for wildcard nodata responses. wildcard nsec */ 704 int nsec3s_seen = 0; /* nsec3s seen */ 705 struct ub_packed_rrset_key* s; 706 size_t i; 707 708 for(i=chase_reply->an_numrrsets; i<chase_reply->an_numrrsets+ 709 chase_reply->ns_numrrsets; i++) { 710 s = chase_reply->rrsets[i]; 711 /* If we encounter an NSEC record, try to use it to prove 712 * NODATA. 713 * This needs to handle the ENT NODATA case. */ 714 if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC) { 715 if(nsec_proves_nodata(s, qchase, &wc)) { 716 has_valid_nsec = 1; 717 /* sets wc-encloser if wildcard applicable */ 718 } 719 if(val_nsec_proves_name_error(s, qchase->qname)) { 720 ce = nsec_closest_encloser(qchase->qname, s); 721 } 722 if(val_nsec_proves_insecuredelegation(s, qchase)) { 723 verbose(VERB_ALGO, "delegation is insecure"); 724 chase_reply->security = sec_status_insecure; 725 return; 726 } 727 } else if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC3) { 728 nsec3s_seen = 1; 729 } 730 } 731 732 /* check to see if we have a wildcard NODATA proof. */ 733 734 /* The wildcard NODATA is 1 NSEC proving that qname does not exist 735 * (and also proving what the closest encloser is), and 1 NSEC 736 * showing the matching wildcard, which must be *.closest_encloser. */ 737 if(wc && !ce) 738 has_valid_nsec = 0; 739 else if(wc && ce) { 740 if(query_dname_compare(wc, ce) != 0) { 741 has_valid_nsec = 0; 742 } 743 } 744 745 if(!has_valid_nsec && nsec3s_seen) { 746 enum sec_status sec = nsec3_prove_nodata(env, ve, 747 chase_reply->rrsets+chase_reply->an_numrrsets, 748 chase_reply->ns_numrrsets, qchase, kkey); 749 if(sec == sec_status_insecure) { 750 verbose(VERB_ALGO, "NODATA response is insecure"); 751 chase_reply->security = sec_status_insecure; 752 return; 753 } else if(sec == sec_status_secure) 754 has_valid_nsec = 1; 755 } 756 757 if(!has_valid_nsec) { 758 verbose(VERB_QUERY, "NODATA response failed to prove NODATA " 759 "status with NSEC/NSEC3"); 760 if(verbosity >= VERB_ALGO) 761 log_dns_msg("Failed NODATA", qchase, chase_reply); 762 chase_reply->security = sec_status_bogus; 763 return; 764 } 765 766 verbose(VERB_ALGO, "successfully validated NODATA response."); 767 chase_reply->security = sec_status_secure; 768 } 769 770 /** 771 * Validate a NAMEERROR signed response -- a response that has a NXDOMAIN 772 * Rcode. 773 * This consists of making certain that the authority section NSEC proves 774 * that the qname doesn't exist and the covering wildcard also doesn't exist.. 775 * 776 * The answer and authority RRsets must have already been verified as secure. 777 * 778 * @param env: module env for verify. 779 * @param ve: validator env for verify. 780 * @param qchase: query that was made. 781 * @param chase_reply: answer to that query to validate. 782 * @param kkey: the key entry, which is trusted, and which matches 783 * the signer of the answer. The key entry isgood(). 784 * @param rcode: adjusted RCODE, in case of RCODE/proof mismatch leniency. 785 */ 786 static void 787 validate_nameerror_response(struct module_env* env, struct val_env* ve, 788 struct query_info* qchase, struct reply_info* chase_reply, 789 struct key_entry_key* kkey, int* rcode) 790 { 791 int has_valid_nsec = 0; 792 int has_valid_wnsec = 0; 793 int nsec3s_seen = 0; 794 struct ub_packed_rrset_key* s; 795 size_t i; 796 797 for(i=chase_reply->an_numrrsets; i<chase_reply->an_numrrsets+ 798 chase_reply->ns_numrrsets; i++) { 799 s = chase_reply->rrsets[i]; 800 if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC) { 801 if(val_nsec_proves_name_error(s, qchase->qname)) 802 has_valid_nsec = 1; 803 if(val_nsec_proves_no_wc(s, qchase->qname, 804 qchase->qname_len)) 805 has_valid_wnsec = 1; 806 if(val_nsec_proves_insecuredelegation(s, qchase)) { 807 verbose(VERB_ALGO, "delegation is insecure"); 808 chase_reply->security = sec_status_insecure; 809 return; 810 } 811 } else if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC3) 812 nsec3s_seen = 1; 813 } 814 815 if((!has_valid_nsec || !has_valid_wnsec) && nsec3s_seen) { 816 /* use NSEC3 proof, both answer and auth rrsets, in case 817 * NSEC3s end up in the answer (due to qtype=NSEC3 or so) */ 818 chase_reply->security = nsec3_prove_nameerror(env, ve, 819 chase_reply->rrsets, chase_reply->an_numrrsets+ 820 chase_reply->ns_numrrsets, qchase, kkey); 821 if(chase_reply->security != sec_status_secure) { 822 verbose(VERB_QUERY, "NameError response failed nsec, " 823 "nsec3 proof was %s", sec_status_to_string( 824 chase_reply->security)); 825 return; 826 } 827 has_valid_nsec = 1; 828 has_valid_wnsec = 1; 829 } 830 831 /* If the message fails to prove either condition, it is bogus. */ 832 if(!has_valid_nsec) { 833 verbose(VERB_QUERY, "NameError response has failed to prove: " 834 "qname does not exist"); 835 chase_reply->security = sec_status_bogus; 836 /* Be lenient with RCODE in NSEC NameError responses */ 837 validate_nodata_response(env, ve, qchase, chase_reply, kkey); 838 if (chase_reply->security == sec_status_secure) 839 *rcode = LDNS_RCODE_NOERROR; 840 return; 841 } 842 843 if(!has_valid_wnsec) { 844 verbose(VERB_QUERY, "NameError response has failed to prove: " 845 "covering wildcard does not exist"); 846 chase_reply->security = sec_status_bogus; 847 /* Be lenient with RCODE in NSEC NameError responses */ 848 validate_nodata_response(env, ve, qchase, chase_reply, kkey); 849 if (chase_reply->security == sec_status_secure) 850 *rcode = LDNS_RCODE_NOERROR; 851 return; 852 } 853 854 /* Otherwise, we consider the message secure. */ 855 verbose(VERB_ALGO, "successfully validated NAME ERROR response."); 856 chase_reply->security = sec_status_secure; 857 } 858 859 /** 860 * Given a referral response, validate rrsets and take least trusted rrset 861 * as the current validation status. 862 * 863 * Note that by the time this method is called, the process of finding the 864 * trusted DNSKEY rrset that signs this response must already have been 865 * completed. 866 * 867 * @param chase_reply: answer to validate. 868 */ 869 static void 870 validate_referral_response(struct reply_info* chase_reply) 871 { 872 size_t i; 873 enum sec_status s; 874 /* message security equals lowest rrset security */ 875 chase_reply->security = sec_status_secure; 876 for(i=0; i<chase_reply->rrset_count; i++) { 877 s = ((struct packed_rrset_data*)chase_reply->rrsets[i] 878 ->entry.data)->security; 879 if(s < chase_reply->security) 880 chase_reply->security = s; 881 } 882 verbose(VERB_ALGO, "validated part of referral response as %s", 883 sec_status_to_string(chase_reply->security)); 884 } 885 886 /** 887 * Given an "ANY" response -- a response that contains an answer to a 888 * qtype==ANY question, with answers. This does no checking that all 889 * types are present. 890 * 891 * NOTE: it may be possible to get parent-side delegation point records 892 * here, which won't all be signed. Right now, this routine relies on the 893 * upstream iterative resolver to not return these responses -- instead 894 * treating them as referrals. 895 * 896 * NOTE: RFC 4035 is silent on this issue, so this may change upon 897 * clarification. Clarification draft -05 says to not check all types are 898 * present. 899 * 900 * Note that by the time this method is called, the process of finding the 901 * trusted DNSKEY rrset that signs this response must already have been 902 * completed. 903 * 904 * @param env: module env for verify. 905 * @param ve: validator env for verify. 906 * @param qchase: query that was made. 907 * @param chase_reply: answer to that query to validate. 908 * @param kkey: the key entry, which is trusted, and which matches 909 * the signer of the answer. The key entry isgood(). 910 */ 911 static void 912 validate_any_response(struct module_env* env, struct val_env* ve, 913 struct query_info* qchase, struct reply_info* chase_reply, 914 struct key_entry_key* kkey) 915 { 916 /* all answer and auth rrsets already verified */ 917 /* but check if a wildcard response is given, then check NSEC/NSEC3 918 * for qname denial to see if wildcard is applicable */ 919 uint8_t* wc = NULL; 920 int wc_NSEC_ok = 0; 921 int nsec3s_seen = 0; 922 size_t i; 923 struct ub_packed_rrset_key* s; 924 925 if(qchase->qtype != LDNS_RR_TYPE_ANY) { 926 log_err("internal error: ANY validation called for non-ANY"); 927 chase_reply->security = sec_status_bogus; 928 return; 929 } 930 931 /* validate the ANSWER section - this will be the answer itself */ 932 for(i=0; i<chase_reply->an_numrrsets; i++) { 933 s = chase_reply->rrsets[i]; 934 935 /* Check to see if the rrset is the result of a wildcard 936 * expansion. If so, an additional check will need to be 937 * made in the authority section. */ 938 if(!val_rrset_wildcard(s, &wc)) { 939 log_nametypeclass(VERB_QUERY, "Positive ANY response" 940 " has inconsistent wildcard sigs:", 941 s->rk.dname, ntohs(s->rk.type), 942 ntohs(s->rk.rrset_class)); 943 chase_reply->security = sec_status_bogus; 944 return; 945 } 946 } 947 948 /* if it was a wildcard, check for NSEC/NSEC3s in both answer 949 * and authority sections (NSEC may be moved to the ANSWER section) */ 950 if(wc != NULL) 951 for(i=0; i<chase_reply->an_numrrsets+chase_reply->ns_numrrsets; 952 i++) { 953 s = chase_reply->rrsets[i]; 954 955 /* If this is a positive wildcard response, and we have a 956 * (just verified) NSEC record, try to use it to 1) prove 957 * that qname doesn't exist and 2) that the correct wildcard 958 * was used. */ 959 if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC) { 960 if(val_nsec_proves_positive_wildcard(s, qchase, wc)) { 961 wc_NSEC_ok = 1; 962 } 963 /* if not, continue looking for proof */ 964 } 965 966 /* Otherwise, if this is a positive wildcard response and 967 * we have NSEC3 records */ 968 if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC3) { 969 nsec3s_seen = 1; 970 } 971 } 972 973 /* If this was a positive wildcard response that we haven't already 974 * proven, and we have NSEC3 records, try to prove it using the NSEC3 975 * records. */ 976 if(wc != NULL && !wc_NSEC_ok && nsec3s_seen) { 977 /* look both in answer and auth section for NSEC3s */ 978 enum sec_status sec = nsec3_prove_wildcard(env, ve, 979 chase_reply->rrsets, 980 chase_reply->an_numrrsets+chase_reply->ns_numrrsets, 981 qchase, kkey, wc); 982 if(sec == sec_status_insecure) { 983 verbose(VERB_ALGO, "Positive ANY wildcard response is " 984 "insecure"); 985 chase_reply->security = sec_status_insecure; 986 return; 987 } else if(sec == sec_status_secure) 988 wc_NSEC_ok = 1; 989 } 990 991 /* If after all this, we still haven't proven the positive wildcard 992 * response, fail. */ 993 if(wc != NULL && !wc_NSEC_ok) { 994 verbose(VERB_QUERY, "positive ANY response was wildcard " 995 "expansion and did not prove original data " 996 "did not exist"); 997 chase_reply->security = sec_status_bogus; 998 return; 999 } 1000 1001 verbose(VERB_ALGO, "Successfully validated positive ANY response"); 1002 chase_reply->security = sec_status_secure; 1003 } 1004 1005 /** 1006 * Validate CNAME response, or DNAME+CNAME. 1007 * This is just like a positive proof, except that this is about a 1008 * DNAME+CNAME. Possible wildcard proof. 1009 * Difference with positive proof is that this routine refuses 1010 * wildcarded DNAMEs. 1011 * 1012 * The answer and authority rrsets must already be verified as secure. 1013 * 1014 * @param env: module env for verify. 1015 * @param ve: validator env for verify. 1016 * @param qchase: query that was made. 1017 * @param chase_reply: answer to that query to validate. 1018 * @param kkey: the key entry, which is trusted, and which matches 1019 * the signer of the answer. The key entry isgood(). 1020 */ 1021 static void 1022 validate_cname_response(struct module_env* env, struct val_env* ve, 1023 struct query_info* qchase, struct reply_info* chase_reply, 1024 struct key_entry_key* kkey) 1025 { 1026 uint8_t* wc = NULL; 1027 int wc_NSEC_ok = 0; 1028 int nsec3s_seen = 0; 1029 size_t i; 1030 struct ub_packed_rrset_key* s; 1031 1032 /* validate the ANSWER section - this will be the CNAME (+DNAME) */ 1033 for(i=0; i<chase_reply->an_numrrsets; i++) { 1034 s = chase_reply->rrsets[i]; 1035 1036 /* Check to see if the rrset is the result of a wildcard 1037 * expansion. If so, an additional check will need to be 1038 * made in the authority section. */ 1039 if(!val_rrset_wildcard(s, &wc)) { 1040 log_nametypeclass(VERB_QUERY, "Cname response has " 1041 "inconsistent wildcard sigs:", s->rk.dname, 1042 ntohs(s->rk.type), ntohs(s->rk.rrset_class)); 1043 chase_reply->security = sec_status_bogus; 1044 return; 1045 } 1046 1047 /* Refuse wildcarded DNAMEs rfc 4597. 1048 * Do not follow a wildcarded DNAME because 1049 * its synthesized CNAME expansion is underdefined */ 1050 if(qchase->qtype != LDNS_RR_TYPE_DNAME && 1051 ntohs(s->rk.type) == LDNS_RR_TYPE_DNAME && wc) { 1052 log_nametypeclass(VERB_QUERY, "cannot validate a " 1053 "wildcarded DNAME:", s->rk.dname, 1054 ntohs(s->rk.type), ntohs(s->rk.rrset_class)); 1055 chase_reply->security = sec_status_bogus; 1056 return; 1057 } 1058 1059 /* If we have found a CNAME, stop looking for one. 1060 * The iterator has placed the CNAME chain in correct 1061 * order. */ 1062 if (ntohs(s->rk.type) == LDNS_RR_TYPE_CNAME) { 1063 break; 1064 } 1065 } 1066 1067 /* AUTHORITY section */ 1068 for(i=chase_reply->an_numrrsets; i<chase_reply->an_numrrsets+ 1069 chase_reply->ns_numrrsets; i++) { 1070 s = chase_reply->rrsets[i]; 1071 1072 /* If this is a positive wildcard response, and we have a 1073 * (just verified) NSEC record, try to use it to 1) prove 1074 * that qname doesn't exist and 2) that the correct wildcard 1075 * was used. */ 1076 if(wc != NULL && ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC) { 1077 if(val_nsec_proves_positive_wildcard(s, qchase, wc)) { 1078 wc_NSEC_ok = 1; 1079 } 1080 /* if not, continue looking for proof */ 1081 } 1082 1083 /* Otherwise, if this is a positive wildcard response and 1084 * we have NSEC3 records */ 1085 if(wc != NULL && ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC3) { 1086 nsec3s_seen = 1; 1087 } 1088 } 1089 1090 /* If this was a positive wildcard response that we haven't already 1091 * proven, and we have NSEC3 records, try to prove it using the NSEC3 1092 * records. */ 1093 if(wc != NULL && !wc_NSEC_ok && nsec3s_seen) { 1094 enum sec_status sec = nsec3_prove_wildcard(env, ve, 1095 chase_reply->rrsets+chase_reply->an_numrrsets, 1096 chase_reply->ns_numrrsets, qchase, kkey, wc); 1097 if(sec == sec_status_insecure) { 1098 verbose(VERB_ALGO, "wildcard CNAME response is " 1099 "insecure"); 1100 chase_reply->security = sec_status_insecure; 1101 return; 1102 } else if(sec == sec_status_secure) 1103 wc_NSEC_ok = 1; 1104 } 1105 1106 /* If after all this, we still haven't proven the positive wildcard 1107 * response, fail. */ 1108 if(wc != NULL && !wc_NSEC_ok) { 1109 verbose(VERB_QUERY, "CNAME response was wildcard " 1110 "expansion and did not prove original data " 1111 "did not exist"); 1112 chase_reply->security = sec_status_bogus; 1113 return; 1114 } 1115 1116 verbose(VERB_ALGO, "Successfully validated CNAME response"); 1117 chase_reply->security = sec_status_secure; 1118 } 1119 1120 /** 1121 * Validate CNAME NOANSWER response, no more data after a CNAME chain. 1122 * This can be a NODATA or a NAME ERROR case, but not both at the same time. 1123 * We don't know because the rcode has been set to NOERROR by the CNAME. 1124 * 1125 * The answer and authority rrsets must already be verified as secure. 1126 * 1127 * @param env: module env for verify. 1128 * @param ve: validator env for verify. 1129 * @param qchase: query that was made. 1130 * @param chase_reply: answer to that query to validate. 1131 * @param kkey: the key entry, which is trusted, and which matches 1132 * the signer of the answer. The key entry isgood(). 1133 */ 1134 static void 1135 validate_cname_noanswer_response(struct module_env* env, struct val_env* ve, 1136 struct query_info* qchase, struct reply_info* chase_reply, 1137 struct key_entry_key* kkey) 1138 { 1139 int nodata_valid_nsec = 0; /* If true, then NODATA has been proven.*/ 1140 uint8_t* ce = NULL; /* for wildcard nodata responses. This is the 1141 proven closest encloser. */ 1142 uint8_t* wc = NULL; /* for wildcard nodata responses. wildcard nsec */ 1143 int nxdomain_valid_nsec = 0; /* if true, namerror has been proven */ 1144 int nxdomain_valid_wnsec = 0; 1145 int nsec3s_seen = 0; /* nsec3s seen */ 1146 struct ub_packed_rrset_key* s; 1147 size_t i; 1148 1149 /* the AUTHORITY section */ 1150 for(i=chase_reply->an_numrrsets; i<chase_reply->an_numrrsets+ 1151 chase_reply->ns_numrrsets; i++) { 1152 s = chase_reply->rrsets[i]; 1153 1154 /* If we encounter an NSEC record, try to use it to prove 1155 * NODATA. This needs to handle the ENT NODATA case. 1156 * Also try to prove NAMEERROR, and absence of a wildcard */ 1157 if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC) { 1158 if(nsec_proves_nodata(s, qchase, &wc)) { 1159 nodata_valid_nsec = 1; 1160 /* set wc encloser if wildcard applicable */ 1161 } 1162 if(val_nsec_proves_name_error(s, qchase->qname)) { 1163 ce = nsec_closest_encloser(qchase->qname, s); 1164 nxdomain_valid_nsec = 1; 1165 } 1166 if(val_nsec_proves_no_wc(s, qchase->qname, 1167 qchase->qname_len)) 1168 nxdomain_valid_wnsec = 1; 1169 if(val_nsec_proves_insecuredelegation(s, qchase)) { 1170 verbose(VERB_ALGO, "delegation is insecure"); 1171 chase_reply->security = sec_status_insecure; 1172 return; 1173 } 1174 } else if(ntohs(s->rk.type) == LDNS_RR_TYPE_NSEC3) { 1175 nsec3s_seen = 1; 1176 } 1177 } 1178 1179 /* check to see if we have a wildcard NODATA proof. */ 1180 1181 /* The wildcard NODATA is 1 NSEC proving that qname does not exists 1182 * (and also proving what the closest encloser is), and 1 NSEC 1183 * showing the matching wildcard, which must be *.closest_encloser. */ 1184 if(wc && !ce) 1185 nodata_valid_nsec = 0; 1186 else if(wc && ce) { 1187 if(query_dname_compare(wc, ce) != 0) { 1188 nodata_valid_nsec = 0; 1189 } 1190 } 1191 if(nxdomain_valid_nsec && !nxdomain_valid_wnsec) { 1192 /* name error is missing wildcard denial proof */ 1193 nxdomain_valid_nsec = 0; 1194 } 1195 1196 if(nodata_valid_nsec && nxdomain_valid_nsec) { 1197 verbose(VERB_QUERY, "CNAMEchain to noanswer proves that name " 1198 "exists and not exists, bogus"); 1199 chase_reply->security = sec_status_bogus; 1200 return; 1201 } 1202 if(!nodata_valid_nsec && !nxdomain_valid_nsec && nsec3s_seen) { 1203 int nodata; 1204 enum sec_status sec = nsec3_prove_nxornodata(env, ve, 1205 chase_reply->rrsets+chase_reply->an_numrrsets, 1206 chase_reply->ns_numrrsets, qchase, kkey, &nodata); 1207 if(sec == sec_status_insecure) { 1208 verbose(VERB_ALGO, "CNAMEchain to noanswer response " 1209 "is insecure"); 1210 chase_reply->security = sec_status_insecure; 1211 return; 1212 } else if(sec == sec_status_secure) { 1213 if(nodata) 1214 nodata_valid_nsec = 1; 1215 else nxdomain_valid_nsec = 1; 1216 } 1217 } 1218 1219 if(!nodata_valid_nsec && !nxdomain_valid_nsec) { 1220 verbose(VERB_QUERY, "CNAMEchain to noanswer response failed " 1221 "to prove status with NSEC/NSEC3"); 1222 if(verbosity >= VERB_ALGO) 1223 log_dns_msg("Failed CNAMEnoanswer", qchase, chase_reply); 1224 chase_reply->security = sec_status_bogus; 1225 return; 1226 } 1227 1228 if(nodata_valid_nsec) 1229 verbose(VERB_ALGO, "successfully validated CNAME chain to a " 1230 "NODATA response."); 1231 else verbose(VERB_ALGO, "successfully validated CNAME chain to a " 1232 "NAMEERROR response."); 1233 chase_reply->security = sec_status_secure; 1234 } 1235 1236 /** 1237 * Process init state for validator. 1238 * Process the INIT state. First tier responses start in the INIT state. 1239 * This is where they are vetted for validation suitability, and the initial 1240 * key search is done. 1241 * 1242 * Currently, events the come through this routine will be either promoted 1243 * to FINISHED/CNAME_RESP (no validation needed), FINDKEY (next step to 1244 * validation), or will be (temporarily) retired and a new priming request 1245 * event will be generated. 1246 * 1247 * @param qstate: query state. 1248 * @param vq: validator query state. 1249 * @param ve: validator shared global environment. 1250 * @param id: module id. 1251 * @return true if the event should be processed further on return, false if 1252 * not. 1253 */ 1254 static int 1255 processInit(struct module_qstate* qstate, struct val_qstate* vq, 1256 struct val_env* ve, int id) 1257 { 1258 uint8_t* lookup_name; 1259 size_t lookup_len; 1260 struct trust_anchor* anchor; 1261 enum val_classification subtype = val_classify_response( 1262 qstate->query_flags, &qstate->qinfo, &vq->qchase, 1263 vq->orig_msg->rep, vq->rrset_skip); 1264 if(vq->restart_count > VAL_MAX_RESTART_COUNT) { 1265 verbose(VERB_ALGO, "restart count exceeded"); 1266 return val_error(qstate, id); 1267 } 1268 verbose(VERB_ALGO, "validator classification %s", 1269 val_classification_to_string(subtype)); 1270 if(subtype == VAL_CLASS_REFERRAL && 1271 vq->rrset_skip < vq->orig_msg->rep->rrset_count) { 1272 /* referral uses the rrset name as qchase, to find keys for 1273 * that rrset */ 1274 vq->qchase.qname = vq->orig_msg->rep-> 1275 rrsets[vq->rrset_skip]->rk.dname; 1276 vq->qchase.qname_len = vq->orig_msg->rep-> 1277 rrsets[vq->rrset_skip]->rk.dname_len; 1278 vq->qchase.qtype = ntohs(vq->orig_msg->rep-> 1279 rrsets[vq->rrset_skip]->rk.type); 1280 vq->qchase.qclass = ntohs(vq->orig_msg->rep-> 1281 rrsets[vq->rrset_skip]->rk.rrset_class); 1282 } 1283 lookup_name = vq->qchase.qname; 1284 lookup_len = vq->qchase.qname_len; 1285 /* for type DS look at the parent side for keys/trustanchor */ 1286 /* also for NSEC not at apex */ 1287 if(vq->qchase.qtype == LDNS_RR_TYPE_DS || 1288 (vq->qchase.qtype == LDNS_RR_TYPE_NSEC && 1289 vq->orig_msg->rep->rrset_count > vq->rrset_skip && 1290 ntohs(vq->orig_msg->rep->rrsets[vq->rrset_skip]->rk.type) == 1291 LDNS_RR_TYPE_NSEC && 1292 !(vq->orig_msg->rep->rrsets[vq->rrset_skip]-> 1293 rk.flags&PACKED_RRSET_NSEC_AT_APEX))) { 1294 dname_remove_label(&lookup_name, &lookup_len); 1295 } 1296 1297 val_mark_indeterminate(vq->chase_reply, qstate->env->anchors, 1298 qstate->env->rrset_cache, qstate->env); 1299 vq->key_entry = NULL; 1300 vq->empty_DS_name = NULL; 1301 vq->ds_rrset = 0; 1302 anchor = anchors_lookup(qstate->env->anchors, 1303 lookup_name, lookup_len, vq->qchase.qclass); 1304 1305 /* Determine the signer/lookup name */ 1306 val_find_signer(subtype, &vq->qchase, vq->orig_msg->rep, 1307 vq->rrset_skip, &vq->signer_name, &vq->signer_len); 1308 if(vq->signer_name != NULL && 1309 !dname_subdomain_c(lookup_name, vq->signer_name)) { 1310 log_nametypeclass(VERB_ALGO, "this signer name is not a parent " 1311 "of lookupname, omitted", vq->signer_name, 0, 0); 1312 vq->signer_name = NULL; 1313 } 1314 if(vq->signer_name == NULL) { 1315 log_nametypeclass(VERB_ALGO, "no signer, using", lookup_name, 1316 0, 0); 1317 } else { 1318 lookup_name = vq->signer_name; 1319 lookup_len = vq->signer_len; 1320 log_nametypeclass(VERB_ALGO, "signer is", lookup_name, 0, 0); 1321 } 1322 1323 /* for NXDOMAIN it could be signed by a parent of the trust anchor */ 1324 if(subtype == VAL_CLASS_NAMEERROR && vq->signer_name && 1325 anchor && dname_strict_subdomain_c(anchor->name, lookup_name)){ 1326 lock_basic_unlock(&anchor->lock); 1327 anchor = anchors_lookup(qstate->env->anchors, 1328 lookup_name, lookup_len, vq->qchase.qclass); 1329 if(!anchor) { /* unsigned parent denies anchor*/ 1330 verbose(VERB_QUERY, "unsigned parent zone denies" 1331 " trust anchor, indeterminate"); 1332 vq->chase_reply->security = sec_status_indeterminate; 1333 vq->state = VAL_FINISHED_STATE; 1334 return 1; 1335 } 1336 verbose(VERB_ALGO, "trust anchor NXDOMAIN by signed parent"); 1337 } else if(subtype == VAL_CLASS_POSITIVE && 1338 qstate->qinfo.qtype == LDNS_RR_TYPE_DNSKEY && 1339 query_dname_compare(lookup_name, qstate->qinfo.qname) == 0) { 1340 /* is a DNSKEY so lookup a bit higher since we want to 1341 * get it from a parent or from trustanchor */ 1342 dname_remove_label(&lookup_name, &lookup_len); 1343 } 1344 1345 if(vq->rrset_skip > 0 || subtype == VAL_CLASS_CNAME || 1346 subtype == VAL_CLASS_REFERRAL) { 1347 /* extract this part of orig_msg into chase_reply for 1348 * the eventual VALIDATE stage */ 1349 val_fill_reply(vq->chase_reply, vq->orig_msg->rep, 1350 vq->rrset_skip, lookup_name, lookup_len, 1351 vq->signer_name); 1352 if(verbosity >= VERB_ALGO) 1353 log_dns_msg("chased extract", &vq->qchase, 1354 vq->chase_reply); 1355 } 1356 1357 vq->key_entry = key_cache_obtain(ve->kcache, lookup_name, lookup_len, 1358 vq->qchase.qclass, qstate->region, *qstate->env->now); 1359 1360 /* there is no key(from DLV) and no trust anchor */ 1361 if(vq->key_entry == NULL && anchor == NULL) { 1362 /*response isn't under a trust anchor, so we cannot validate.*/ 1363 vq->chase_reply->security = sec_status_indeterminate; 1364 /* go to finished state to cache this result */ 1365 vq->state = VAL_FINISHED_STATE; 1366 return 1; 1367 } 1368 /* if not key, or if keyentry is *above* the trustanchor, i.e. 1369 * the keyentry is based on another (higher) trustanchor */ 1370 else if(vq->key_entry == NULL || (anchor && 1371 dname_strict_subdomain_c(anchor->name, vq->key_entry->name))) { 1372 /* trust anchor is an 'unsigned' trust anchor */ 1373 if(anchor && anchor->numDS == 0 && anchor->numDNSKEY == 0) { 1374 vq->chase_reply->security = sec_status_insecure; 1375 val_mark_insecure(vq->chase_reply, anchor->name, 1376 qstate->env->rrset_cache, qstate->env); 1377 lock_basic_unlock(&anchor->lock); 1378 vq->dlv_checked=1; /* skip DLV check */ 1379 /* go to finished state to cache this result */ 1380 vq->state = VAL_FINISHED_STATE; 1381 return 1; 1382 } 1383 /* fire off a trust anchor priming query. */ 1384 verbose(VERB_DETAIL, "prime trust anchor"); 1385 if(!prime_trust_anchor(qstate, vq, id, anchor)) { 1386 lock_basic_unlock(&anchor->lock); 1387 return val_error(qstate, id); 1388 } 1389 lock_basic_unlock(&anchor->lock); 1390 /* and otherwise, don't continue processing this event. 1391 * (it will be reactivated when the priming query returns). */ 1392 vq->state = VAL_FINDKEY_STATE; 1393 return 0; 1394 } 1395 if(anchor) { 1396 lock_basic_unlock(&anchor->lock); 1397 } 1398 1399 if(key_entry_isnull(vq->key_entry)) { 1400 /* response is under a null key, so we cannot validate 1401 * However, we do set the status to INSECURE, since it is 1402 * essentially proven insecure. */ 1403 vq->chase_reply->security = sec_status_insecure; 1404 val_mark_insecure(vq->chase_reply, vq->key_entry->name, 1405 qstate->env->rrset_cache, qstate->env); 1406 /* go to finished state to cache this result */ 1407 vq->state = VAL_FINISHED_STATE; 1408 return 1; 1409 } else if(key_entry_isbad(vq->key_entry)) { 1410 /* key is bad, chain is bad, reply is bogus */ 1411 errinf_dname(qstate, "key for validation", vq->key_entry->name); 1412 errinf(qstate, "is marked as invalid"); 1413 if(key_entry_get_reason(vq->key_entry)) { 1414 errinf(qstate, "because of a previous"); 1415 errinf(qstate, key_entry_get_reason(vq->key_entry)); 1416 } 1417 /* no retries, stop bothering the authority until timeout */ 1418 vq->restart_count = VAL_MAX_RESTART_COUNT; 1419 vq->chase_reply->security = sec_status_bogus; 1420 vq->state = VAL_FINISHED_STATE; 1421 return 1; 1422 } 1423 1424 /* otherwise, we have our "closest" cached key -- continue 1425 * processing in the next state. */ 1426 vq->state = VAL_FINDKEY_STATE; 1427 return 1; 1428 } 1429 1430 /** 1431 * Process the FINDKEY state. Generally this just calculates the next name 1432 * to query and either issues a DS or a DNSKEY query. It will check to see 1433 * if the correct key has already been reached, in which case it will 1434 * advance the event to the next state. 1435 * 1436 * @param qstate: query state. 1437 * @param vq: validator query state. 1438 * @param id: module id. 1439 * @return true if the event should be processed further on return, false if 1440 * not. 1441 */ 1442 static int 1443 processFindKey(struct module_qstate* qstate, struct val_qstate* vq, int id) 1444 { 1445 uint8_t* target_key_name, *current_key_name; 1446 size_t target_key_len; 1447 int strip_lab; 1448 1449 log_query_info(VERB_ALGO, "validator: FindKey", &vq->qchase); 1450 /* We know that state.key_entry is not 0 or bad key -- if it were, 1451 * then previous processing should have directed this event to 1452 * a different state. 1453 * It could be an isnull key, which signals that a DLV was just 1454 * done and the DNSKEY after the DLV failed with dnssec-retry state 1455 * and the DNSKEY has to be performed again. */ 1456 log_assert(vq->key_entry && !key_entry_isbad(vq->key_entry)); 1457 if(key_entry_isnull(vq->key_entry)) { 1458 if(!generate_request(qstate, id, vq->ds_rrset->rk.dname, 1459 vq->ds_rrset->rk.dname_len, LDNS_RR_TYPE_DNSKEY, 1460 vq->qchase.qclass, BIT_CD)) { 1461 log_err("mem error generating DNSKEY request"); 1462 return val_error(qstate, id); 1463 } 1464 return 0; 1465 } 1466 1467 target_key_name = vq->signer_name; 1468 target_key_len = vq->signer_len; 1469 if(!target_key_name) { 1470 target_key_name = vq->qchase.qname; 1471 target_key_len = vq->qchase.qname_len; 1472 } 1473 1474 current_key_name = vq->key_entry->name; 1475 1476 /* If our current key entry matches our target, then we are done. */ 1477 if(query_dname_compare(target_key_name, current_key_name) == 0) { 1478 vq->state = VAL_VALIDATE_STATE; 1479 return 1; 1480 } 1481 1482 if(vq->empty_DS_name) { 1483 /* if the last empty nonterminal/emptyDS name we detected is 1484 * below the current key, use that name to make progress 1485 * along the chain of trust */ 1486 if(query_dname_compare(target_key_name, 1487 vq->empty_DS_name) == 0) { 1488 /* do not query for empty_DS_name again */ 1489 verbose(VERB_ALGO, "Cannot retrieve DS for signature"); 1490 errinf(qstate, "no signatures"); 1491 errinf_origin(qstate, qstate->reply_origin); 1492 vq->chase_reply->security = sec_status_bogus; 1493 vq->state = VAL_FINISHED_STATE; 1494 return 1; 1495 } 1496 current_key_name = vq->empty_DS_name; 1497 } 1498 1499 log_nametypeclass(VERB_ALGO, "current keyname", current_key_name, 1500 LDNS_RR_TYPE_DNSKEY, LDNS_RR_CLASS_IN); 1501 log_nametypeclass(VERB_ALGO, "target keyname", target_key_name, 1502 LDNS_RR_TYPE_DNSKEY, LDNS_RR_CLASS_IN); 1503 /* assert we are walking down the DNS tree */ 1504 if(!dname_subdomain_c(target_key_name, current_key_name)) { 1505 verbose(VERB_ALGO, "bad signer name"); 1506 vq->chase_reply->security = sec_status_bogus; 1507 vq->state = VAL_FINISHED_STATE; 1508 return 1; 1509 } 1510 /* so this value is >= -1 */ 1511 strip_lab = dname_count_labels(target_key_name) - 1512 dname_count_labels(current_key_name) - 1; 1513 log_assert(strip_lab >= -1); 1514 verbose(VERB_ALGO, "striplab %d", strip_lab); 1515 if(strip_lab > 0) { 1516 dname_remove_labels(&target_key_name, &target_key_len, 1517 strip_lab); 1518 } 1519 log_nametypeclass(VERB_ALGO, "next keyname", target_key_name, 1520 LDNS_RR_TYPE_DNSKEY, LDNS_RR_CLASS_IN); 1521 1522 /* The next step is either to query for the next DS, or to query 1523 * for the next DNSKEY. */ 1524 if(vq->ds_rrset) 1525 log_nametypeclass(VERB_ALGO, "DS RRset", vq->ds_rrset->rk.dname, LDNS_RR_TYPE_DS, LDNS_RR_CLASS_IN); 1526 else verbose(VERB_ALGO, "No DS RRset"); 1527 1528 if(vq->ds_rrset && query_dname_compare(vq->ds_rrset->rk.dname, 1529 vq->key_entry->name) != 0) { 1530 if(!generate_request(qstate, id, vq->ds_rrset->rk.dname, 1531 vq->ds_rrset->rk.dname_len, LDNS_RR_TYPE_DNSKEY, 1532 vq->qchase.qclass, BIT_CD)) { 1533 log_err("mem error generating DNSKEY request"); 1534 return val_error(qstate, id); 1535 } 1536 return 0; 1537 } 1538 1539 if(!vq->ds_rrset || query_dname_compare(vq->ds_rrset->rk.dname, 1540 target_key_name) != 0) { 1541 /* check if there is a cache entry : pick up an NSEC if 1542 * there is no DS, check if that NSEC has DS-bit unset, and 1543 * thus can disprove the secure delagation we seek. 1544 * We can then use that NSEC even in the absence of a SOA 1545 * record that would be required by the iterator to supply 1546 * a completely protocol-correct response. 1547 * Uses negative cache for NSEC3 lookup of DS responses. */ 1548 /* only if cache not blacklisted, of course */ 1549 struct dns_msg* msg; 1550 if(!qstate->blacklist && !vq->chain_blacklist && 1551 (msg=val_find_DS(qstate->env, target_key_name, 1552 target_key_len, vq->qchase.qclass, qstate->region, 1553 vq->key_entry->name)) ) { 1554 verbose(VERB_ALGO, "Process cached DS response"); 1555 process_ds_response(qstate, vq, id, LDNS_RCODE_NOERROR, 1556 msg, &msg->qinfo, NULL); 1557 return 1; /* continue processing ds-response results */ 1558 } 1559 if(!generate_request(qstate, id, target_key_name, 1560 target_key_len, LDNS_RR_TYPE_DS, vq->qchase.qclass, 1561 BIT_CD)) { 1562 log_err("mem error generating DS request"); 1563 return val_error(qstate, id); 1564 } 1565 return 0; 1566 } 1567 1568 /* Otherwise, it is time to query for the DNSKEY */ 1569 if(!generate_request(qstate, id, vq->ds_rrset->rk.dname, 1570 vq->ds_rrset->rk.dname_len, LDNS_RR_TYPE_DNSKEY, 1571 vq->qchase.qclass, BIT_CD)) { 1572 log_err("mem error generating DNSKEY request"); 1573 return val_error(qstate, id); 1574 } 1575 1576 return 0; 1577 } 1578 1579 /** 1580 * Process the VALIDATE stage, the init and findkey stages are finished, 1581 * and the right keys are available to validate the response. 1582 * Or, there are no keys available, in order to invalidate the response. 1583 * 1584 * After validation, the status is recorded in the message and rrsets, 1585 * and finished state is started. 1586 * 1587 * @param qstate: query state. 1588 * @param vq: validator query state. 1589 * @param ve: validator shared global environment. 1590 * @param id: module id. 1591 * @return true if the event should be processed further on return, false if 1592 * not. 1593 */ 1594 static int 1595 processValidate(struct module_qstate* qstate, struct val_qstate* vq, 1596 struct val_env* ve, int id) 1597 { 1598 enum val_classification subtype; 1599 int rcode; 1600 1601 if(!vq->key_entry) { 1602 verbose(VERB_ALGO, "validate: no key entry, failed"); 1603 return val_error(qstate, id); 1604 } 1605 1606 /* This is the default next state. */ 1607 vq->state = VAL_FINISHED_STATE; 1608 1609 /* Unsigned responses must be underneath a "null" key entry.*/ 1610 if(key_entry_isnull(vq->key_entry)) { 1611 verbose(VERB_DETAIL, "Verified that %sresponse is INSECURE", 1612 vq->signer_name?"":"unsigned "); 1613 vq->chase_reply->security = sec_status_insecure; 1614 val_mark_insecure(vq->chase_reply, vq->key_entry->name, 1615 qstate->env->rrset_cache, qstate->env); 1616 key_cache_insert(ve->kcache, vq->key_entry, qstate); 1617 return 1; 1618 } 1619 1620 if(key_entry_isbad(vq->key_entry)) { 1621 log_nametypeclass(VERB_DETAIL, "Could not establish a chain " 1622 "of trust to keys for", vq->key_entry->name, 1623 LDNS_RR_TYPE_DNSKEY, vq->key_entry->key_class); 1624 vq->chase_reply->security = sec_status_bogus; 1625 errinf(qstate, "while building chain of trust"); 1626 if(vq->restart_count >= VAL_MAX_RESTART_COUNT) 1627 key_cache_insert(ve->kcache, vq->key_entry, qstate); 1628 return 1; 1629 } 1630 1631 /* signerName being null is the indicator that this response was 1632 * unsigned */ 1633 if(vq->signer_name == NULL) { 1634 log_query_info(VERB_ALGO, "processValidate: state has no " 1635 "signer name", &vq->qchase); 1636 verbose(VERB_DETAIL, "Could not establish validation of " 1637 "INSECURE status of unsigned response."); 1638 errinf(qstate, "no signatures"); 1639 errinf_origin(qstate, qstate->reply_origin); 1640 vq->chase_reply->security = sec_status_bogus; 1641 return 1; 1642 } 1643 subtype = val_classify_response(qstate->query_flags, &qstate->qinfo, 1644 &vq->qchase, vq->orig_msg->rep, vq->rrset_skip); 1645 1646 /* check signatures in the message; 1647 * answer and authority must be valid, additional is only checked. */ 1648 if(!validate_msg_signatures(qstate, qstate->env, ve, &vq->qchase, 1649 vq->chase_reply, vq->key_entry)) { 1650 /* workaround bad recursor out there that truncates (even 1651 * with EDNS4k) to 512 by removing RRSIG from auth section 1652 * for positive replies*/ 1653 if((subtype == VAL_CLASS_POSITIVE || subtype == VAL_CLASS_ANY 1654 || subtype == VAL_CLASS_CNAME) && 1655 detect_wrongly_truncated(vq->orig_msg->rep)) { 1656 /* truncate the message some more */ 1657 vq->orig_msg->rep->ns_numrrsets = 0; 1658 vq->orig_msg->rep->ar_numrrsets = 0; 1659 vq->orig_msg->rep->rrset_count = 1660 vq->orig_msg->rep->an_numrrsets; 1661 vq->chase_reply->ns_numrrsets = 0; 1662 vq->chase_reply->ar_numrrsets = 0; 1663 vq->chase_reply->rrset_count = 1664 vq->chase_reply->an_numrrsets; 1665 qstate->errinf = NULL; 1666 } 1667 else { 1668 verbose(VERB_DETAIL, "Validate: message contains " 1669 "bad rrsets"); 1670 return 1; 1671 } 1672 } 1673 1674 switch(subtype) { 1675 case VAL_CLASS_POSITIVE: 1676 verbose(VERB_ALGO, "Validating a positive response"); 1677 validate_positive_response(qstate->env, ve, 1678 &vq->qchase, vq->chase_reply, vq->key_entry); 1679 verbose(VERB_DETAIL, "validate(positive): %s", 1680 sec_status_to_string( 1681 vq->chase_reply->security)); 1682 break; 1683 1684 case VAL_CLASS_NODATA: 1685 verbose(VERB_ALGO, "Validating a nodata response"); 1686 validate_nodata_response(qstate->env, ve, 1687 &vq->qchase, vq->chase_reply, vq->key_entry); 1688 verbose(VERB_DETAIL, "validate(nodata): %s", 1689 sec_status_to_string( 1690 vq->chase_reply->security)); 1691 break; 1692 1693 case VAL_CLASS_NAMEERROR: 1694 rcode = (int)FLAGS_GET_RCODE(vq->orig_msg->rep->flags); 1695 verbose(VERB_ALGO, "Validating a nxdomain response"); 1696 validate_nameerror_response(qstate->env, ve, 1697 &vq->qchase, vq->chase_reply, vq->key_entry, &rcode); 1698 verbose(VERB_DETAIL, "validate(nxdomain): %s", 1699 sec_status_to_string( 1700 vq->chase_reply->security)); 1701 FLAGS_SET_RCODE(vq->orig_msg->rep->flags, rcode); 1702 FLAGS_SET_RCODE(vq->chase_reply->flags, rcode); 1703 break; 1704 1705 case VAL_CLASS_CNAME: 1706 verbose(VERB_ALGO, "Validating a cname response"); 1707 validate_cname_response(qstate->env, ve, 1708 &vq->qchase, vq->chase_reply, vq->key_entry); 1709 verbose(VERB_DETAIL, "validate(cname): %s", 1710 sec_status_to_string( 1711 vq->chase_reply->security)); 1712 break; 1713 1714 case VAL_CLASS_CNAMENOANSWER: 1715 verbose(VERB_ALGO, "Validating a cname noanswer " 1716 "response"); 1717 validate_cname_noanswer_response(qstate->env, ve, 1718 &vq->qchase, vq->chase_reply, vq->key_entry); 1719 verbose(VERB_DETAIL, "validate(cname_noanswer): %s", 1720 sec_status_to_string( 1721 vq->chase_reply->security)); 1722 break; 1723 1724 case VAL_CLASS_REFERRAL: 1725 verbose(VERB_ALGO, "Validating a referral response"); 1726 validate_referral_response(vq->chase_reply); 1727 verbose(VERB_DETAIL, "validate(referral): %s", 1728 sec_status_to_string( 1729 vq->chase_reply->security)); 1730 break; 1731 1732 case VAL_CLASS_ANY: 1733 verbose(VERB_ALGO, "Validating a positive ANY " 1734 "response"); 1735 validate_any_response(qstate->env, ve, &vq->qchase, 1736 vq->chase_reply, vq->key_entry); 1737 verbose(VERB_DETAIL, "validate(positive_any): %s", 1738 sec_status_to_string( 1739 vq->chase_reply->security)); 1740 break; 1741 1742 default: 1743 log_err("validate: unhandled response subtype: %d", 1744 subtype); 1745 } 1746 if(vq->chase_reply->security == sec_status_bogus) { 1747 if(subtype == VAL_CLASS_POSITIVE) 1748 errinf(qstate, "wildcard"); 1749 else errinf(qstate, val_classification_to_string(subtype)); 1750 errinf(qstate, "proof failed"); 1751 errinf_origin(qstate, qstate->reply_origin); 1752 } 1753 1754 return 1; 1755 } 1756 1757 /** 1758 * Init DLV check. 1759 * Called when a query is determined by other trust anchors to be insecure 1760 * (or indeterminate). Then we look if there is a key in the DLV. 1761 * Performs aggressive negative cache check to see if there is no key. 1762 * Otherwise, spawns a DLV query, and changes to the DLV wait state. 1763 * 1764 * @param qstate: query state. 1765 * @param vq: validator query state. 1766 * @param ve: validator shared global environment. 1767 * @param id: module id. 1768 * @return true if there is no DLV. 1769 * false: processing is finished for the validator operate(). 1770 * This function may exit in three ways: 1771 * o no DLV (agressive cache), so insecure. (true) 1772 * o error - stop processing (false) 1773 * o DLV lookup was started, stop processing (false) 1774 */ 1775 static int 1776 val_dlv_init(struct module_qstate* qstate, struct val_qstate* vq, 1777 struct val_env* ve, int id) 1778 { 1779 uint8_t* nm; 1780 size_t nm_len; 1781 /* there must be a DLV configured */ 1782 log_assert(qstate->env->anchors->dlv_anchor); 1783 /* this bool is true to avoid looping in the DLV checks */ 1784 log_assert(vq->dlv_checked); 1785 1786 /* init the DLV lookup variables */ 1787 vq->dlv_lookup_name = NULL; 1788 vq->dlv_lookup_name_len = 0; 1789 vq->dlv_insecure_at = NULL; 1790 vq->dlv_insecure_at_len = 0; 1791 1792 /* Determine the name for which we want to lookup DLV. 1793 * This name is for the current message, or 1794 * for the current RRset for CNAME, referral subtypes. 1795 * If there is a signer, use that, otherwise the domain name */ 1796 if(vq->signer_name) { 1797 nm = vq->signer_name; 1798 nm_len = vq->signer_len; 1799 } else { 1800 /* use qchase */ 1801 nm = vq->qchase.qname; 1802 nm_len = vq->qchase.qname_len; 1803 if(vq->qchase.qtype == LDNS_RR_TYPE_DS) 1804 dname_remove_label(&nm, &nm_len); 1805 } 1806 log_nametypeclass(VERB_ALGO, "DLV init look", nm, LDNS_RR_TYPE_DS, 1807 vq->qchase.qclass); 1808 log_assert(nm && nm_len); 1809 /* sanity check: no DLV lookups below the DLV anchor itself. 1810 * Like, an securely insecure delegation there makes no sense. */ 1811 if(dname_subdomain_c(nm, qstate->env->anchors->dlv_anchor->name)) { 1812 verbose(VERB_ALGO, "DLV lookup within DLV repository denied"); 1813 return 1; 1814 } 1815 /* concat name (minus root label) + dlv name */ 1816 vq->dlv_lookup_name_len = nm_len - 1 + 1817 qstate->env->anchors->dlv_anchor->namelen; 1818 vq->dlv_lookup_name = regional_alloc(qstate->region, 1819 vq->dlv_lookup_name_len); 1820 if(!vq->dlv_lookup_name) { 1821 log_err("Out of memory preparing DLV lookup"); 1822 return val_error(qstate, id); 1823 } 1824 memmove(vq->dlv_lookup_name, nm, nm_len-1); 1825 memmove(vq->dlv_lookup_name+nm_len-1, 1826 qstate->env->anchors->dlv_anchor->name, 1827 qstate->env->anchors->dlv_anchor->namelen); 1828 log_nametypeclass(VERB_ALGO, "DLV name", vq->dlv_lookup_name, 1829 LDNS_RR_TYPE_DLV, vq->qchase.qclass); 1830 1831 /* determine where the insecure point was determined, the DLV must 1832 * be equal or below that to continue building the trust chain 1833 * down. May be NULL if no trust chain was built yet */ 1834 nm = NULL; 1835 if(vq->key_entry && key_entry_isnull(vq->key_entry)) { 1836 nm = vq->key_entry->name; 1837 nm_len = vq->key_entry->namelen; 1838 } 1839 if(nm) { 1840 vq->dlv_insecure_at_len = nm_len - 1 + 1841 qstate->env->anchors->dlv_anchor->namelen; 1842 vq->dlv_insecure_at = regional_alloc(qstate->region, 1843 vq->dlv_insecure_at_len); 1844 if(!vq->dlv_insecure_at) { 1845 log_err("Out of memory preparing DLV lookup"); 1846 return val_error(qstate, id); 1847 } 1848 memmove(vq->dlv_insecure_at, nm, nm_len-1); 1849 memmove(vq->dlv_insecure_at+nm_len-1, 1850 qstate->env->anchors->dlv_anchor->name, 1851 qstate->env->anchors->dlv_anchor->namelen); 1852 log_nametypeclass(VERB_ALGO, "insecure_at", 1853 vq->dlv_insecure_at, 0, vq->qchase.qclass); 1854 } 1855 1856 /* If we can find the name in the aggressive negative cache, 1857 * give up; insecure is the answer */ 1858 while(val_neg_dlvlookup(ve->neg_cache, vq->dlv_lookup_name, 1859 vq->dlv_lookup_name_len, vq->qchase.qclass, 1860 qstate->env->rrset_cache, *qstate->env->now)) { 1861 /* go up */ 1862 dname_remove_label(&vq->dlv_lookup_name, 1863 &vq->dlv_lookup_name_len); 1864 /* too high? */ 1865 if(!dname_subdomain_c(vq->dlv_lookup_name, 1866 qstate->env->anchors->dlv_anchor->name)) { 1867 verbose(VERB_ALGO, "ask above dlv repo"); 1868 return 1; /* Above the repo is insecure */ 1869 } 1870 /* above chain of trust? */ 1871 if(vq->dlv_insecure_at && !dname_subdomain_c( 1872 vq->dlv_lookup_name, vq->dlv_insecure_at)) { 1873 verbose(VERB_ALGO, "ask above insecure endpoint"); 1874 return 1; 1875 } 1876 } 1877 1878 /* perform a lookup for the DLV; with validation */ 1879 vq->state = VAL_DLVLOOKUP_STATE; 1880 if(!generate_request(qstate, id, vq->dlv_lookup_name, 1881 vq->dlv_lookup_name_len, LDNS_RR_TYPE_DLV, 1882 vq->qchase.qclass, 0)) { 1883 return val_error(qstate, id); 1884 } 1885 1886 /* Find the closest encloser DLV from the repository. 1887 * then that is used to build another chain of trust 1888 * This may first require a query 'too low' that has NSECs in 1889 * the answer, from which we determine the closest encloser DLV. 1890 * When determine the closest encloser, skip empty nonterminals, 1891 * since we want a nonempty node in the DLV repository. */ 1892 1893 return 0; 1894 } 1895 1896 /** 1897 * The Finished state. The validation status (good or bad) has been determined. 1898 * 1899 * @param qstate: query state. 1900 * @param vq: validator query state. 1901 * @param ve: validator shared global environment. 1902 * @param id: module id. 1903 * @return true if the event should be processed further on return, false if 1904 * not. 1905 */ 1906 static int 1907 processFinished(struct module_qstate* qstate, struct val_qstate* vq, 1908 struct val_env* ve, int id) 1909 { 1910 enum val_classification subtype = val_classify_response( 1911 qstate->query_flags, &qstate->qinfo, &vq->qchase, 1912 vq->orig_msg->rep, vq->rrset_skip); 1913 1914 /* if the result is insecure or indeterminate and we have not 1915 * checked the DLV yet, check the DLV */ 1916 if((vq->chase_reply->security == sec_status_insecure || 1917 vq->chase_reply->security == sec_status_indeterminate) && 1918 qstate->env->anchors->dlv_anchor && !vq->dlv_checked) { 1919 vq->dlv_checked = 1; 1920 if(!val_dlv_init(qstate, vq, ve, id)) 1921 return 0; 1922 } 1923 1924 /* store overall validation result in orig_msg */ 1925 if(vq->rrset_skip == 0) 1926 vq->orig_msg->rep->security = vq->chase_reply->security; 1927 else if(subtype != VAL_CLASS_REFERRAL || 1928 vq->rrset_skip < vq->orig_msg->rep->an_numrrsets + 1929 vq->orig_msg->rep->ns_numrrsets) { 1930 /* ignore sec status of additional section if a referral 1931 * type message skips there and 1932 * use the lowest security status as end result. */ 1933 if(vq->chase_reply->security < vq->orig_msg->rep->security) 1934 vq->orig_msg->rep->security = 1935 vq->chase_reply->security; 1936 } 1937 1938 if(subtype == VAL_CLASS_REFERRAL) { 1939 /* for a referral, move to next unchecked rrset and check it*/ 1940 vq->rrset_skip = val_next_unchecked(vq->orig_msg->rep, 1941 vq->rrset_skip); 1942 if(vq->rrset_skip < vq->orig_msg->rep->rrset_count) { 1943 /* and restart for this rrset */ 1944 verbose(VERB_ALGO, "validator: go to next rrset"); 1945 vq->chase_reply->security = sec_status_unchecked; 1946 vq->dlv_checked = 0; /* can do DLV for this RR */ 1947 vq->state = VAL_INIT_STATE; 1948 return 1; 1949 } 1950 /* referral chase is done */ 1951 } 1952 if(vq->chase_reply->security != sec_status_bogus && 1953 subtype == VAL_CLASS_CNAME) { 1954 /* chase the CNAME; process next part of the message */ 1955 if(!val_chase_cname(&vq->qchase, vq->orig_msg->rep, 1956 &vq->rrset_skip)) { 1957 verbose(VERB_ALGO, "validator: failed to chase CNAME"); 1958 vq->orig_msg->rep->security = sec_status_bogus; 1959 } else { 1960 /* restart process for new qchase at rrset_skip */ 1961 log_query_info(VERB_ALGO, "validator: chased to", 1962 &vq->qchase); 1963 vq->chase_reply->security = sec_status_unchecked; 1964 vq->dlv_checked = 0; /* can do DLV for this RR */ 1965 vq->state = VAL_INIT_STATE; 1966 return 1; 1967 } 1968 } 1969 1970 if(vq->orig_msg->rep->security == sec_status_secure) { 1971 /* If the message is secure, check that all rrsets are 1972 * secure (i.e. some inserted RRset for CNAME chain with 1973 * a different signer name). And drop additional rrsets 1974 * that are not secure (if clean-additional option is set) */ 1975 /* this may cause the msg to be marked bogus */ 1976 val_check_nonsecure(ve, vq->orig_msg->rep); 1977 if(vq->orig_msg->rep->security == sec_status_secure) { 1978 log_query_info(VERB_DETAIL, "validation success", 1979 &qstate->qinfo); 1980 } 1981 } 1982 1983 /* if the result is bogus - set message ttl to bogus ttl to avoid 1984 * endless bogus revalidation */ 1985 if(vq->orig_msg->rep->security == sec_status_bogus) { 1986 /* see if we can try again to fetch data */ 1987 if(vq->restart_count < VAL_MAX_RESTART_COUNT) { 1988 int restart_count = vq->restart_count+1; 1989 verbose(VERB_ALGO, "validation failed, " 1990 "blacklist and retry to fetch data"); 1991 val_blacklist(&qstate->blacklist, qstate->region, 1992 qstate->reply_origin, 0); 1993 qstate->reply_origin = NULL; 1994 qstate->errinf = NULL; 1995 memset(vq, 0, sizeof(*vq)); 1996 vq->restart_count = restart_count; 1997 vq->state = VAL_INIT_STATE; 1998 verbose(VERB_ALGO, "pass back to next module"); 1999 qstate->ext_state[id] = module_restart_next; 2000 return 0; 2001 } 2002 2003 vq->orig_msg->rep->ttl = ve->bogus_ttl; 2004 vq->orig_msg->rep->prefetch_ttl = 2005 PREFETCH_TTL_CALC(vq->orig_msg->rep->ttl); 2006 if(qstate->env->cfg->val_log_level >= 1 && 2007 !qstate->env->cfg->val_log_squelch) { 2008 if(qstate->env->cfg->val_log_level < 2) 2009 log_query_info(0, "validation failure", 2010 &qstate->qinfo); 2011 else { 2012 char* err = errinf_to_str(qstate); 2013 if(err) log_info("%s", err); 2014 free(err); 2015 } 2016 } 2017 /* If we are in permissive mode, bogus gets indeterminate */ 2018 if(ve->permissive_mode) 2019 vq->orig_msg->rep->security = sec_status_indeterminate; 2020 } 2021 2022 /* store results in cache */ 2023 if(qstate->query_flags&BIT_RD) { 2024 /* if secure, this will override cache anyway, no need 2025 * to check if from parentNS */ 2026 if(!dns_cache_store(qstate->env, &vq->orig_msg->qinfo, 2027 vq->orig_msg->rep, 0, qstate->prefetch_leeway, 0, NULL, 2028 qstate->query_flags)) { 2029 log_err("out of memory caching validator results"); 2030 } 2031 } else { 2032 /* for a referral, store the verified RRsets */ 2033 /* and this does not get prefetched, so no leeway */ 2034 if(!dns_cache_store(qstate->env, &vq->orig_msg->qinfo, 2035 vq->orig_msg->rep, 1, 0, 0, NULL, 2036 qstate->query_flags)) { 2037 log_err("out of memory caching validator results"); 2038 } 2039 } 2040 qstate->return_rcode = LDNS_RCODE_NOERROR; 2041 qstate->return_msg = vq->orig_msg; 2042 qstate->ext_state[id] = module_finished; 2043 return 0; 2044 } 2045 2046 /** 2047 * The DLVLookup state. Process DLV lookups. 2048 * 2049 * @param qstate: query state. 2050 * @param vq: validator query state. 2051 * @param ve: validator shared global environment. 2052 * @param id: module id. 2053 * @return true if the event should be processed further on return, false if 2054 * not. 2055 */ 2056 static int 2057 processDLVLookup(struct module_qstate* qstate, struct val_qstate* vq, 2058 struct val_env* ve, int id) 2059 { 2060 /* see if this we are ready to continue normal resolution */ 2061 /* we may need more DLV lookups */ 2062 if(vq->dlv_status==dlv_error) 2063 verbose(VERB_ALGO, "DLV woke up with status dlv_error"); 2064 else if(vq->dlv_status==dlv_success) 2065 verbose(VERB_ALGO, "DLV woke up with status dlv_success"); 2066 else if(vq->dlv_status==dlv_ask_higher) 2067 verbose(VERB_ALGO, "DLV woke up with status dlv_ask_higher"); 2068 else if(vq->dlv_status==dlv_there_is_no_dlv) 2069 verbose(VERB_ALGO, "DLV woke up with status dlv_there_is_no_dlv"); 2070 else verbose(VERB_ALGO, "DLV woke up with status unknown"); 2071 2072 if(vq->dlv_status == dlv_error) { 2073 verbose(VERB_QUERY, "failed DLV lookup"); 2074 return val_error(qstate, id); 2075 } else if(vq->dlv_status == dlv_success) { 2076 uint8_t* nm; 2077 size_t nmlen; 2078 /* chain continues with DNSKEY, continue in FINDKEY */ 2079 vq->state = VAL_FINDKEY_STATE; 2080 2081 /* strip off the DLV suffix from the name; could result in . */ 2082 log_assert(dname_subdomain_c(vq->ds_rrset->rk.dname, 2083 qstate->env->anchors->dlv_anchor->name)); 2084 nmlen = vq->ds_rrset->rk.dname_len - 2085 qstate->env->anchors->dlv_anchor->namelen + 1; 2086 nm = regional_alloc_init(qstate->region, 2087 vq->ds_rrset->rk.dname, nmlen); 2088 if(!nm) { 2089 log_err("Out of memory in DLVLook"); 2090 return val_error(qstate, id); 2091 } 2092 nm[nmlen-1] = 0; 2093 2094 vq->ds_rrset->rk.dname = nm; 2095 vq->ds_rrset->rk.dname_len = nmlen; 2096 2097 /* create a nullentry for the key so the dnskey lookup 2098 * can be retried after a validation failure for it */ 2099 vq->key_entry = key_entry_create_null(qstate->region, 2100 nm, nmlen, vq->qchase.qclass, 0, 0); 2101 if(!vq->key_entry) { 2102 log_err("Out of memory in DLVLook"); 2103 return val_error(qstate, id); 2104 } 2105 2106 if(!generate_request(qstate, id, vq->ds_rrset->rk.dname, 2107 vq->ds_rrset->rk.dname_len, LDNS_RR_TYPE_DNSKEY, 2108 vq->qchase.qclass, BIT_CD)) { 2109 log_err("mem error generating DNSKEY request"); 2110 return val_error(qstate, id); 2111 } 2112 return 0; 2113 } else if(vq->dlv_status == dlv_there_is_no_dlv) { 2114 /* continue with the insecure result we got */ 2115 vq->state = VAL_FINISHED_STATE; 2116 return 1; 2117 } 2118 log_assert(vq->dlv_status == dlv_ask_higher); 2119 2120 /* ask higher, make sure we stay in DLV repo, below dlv_at */ 2121 if(!dname_subdomain_c(vq->dlv_lookup_name, 2122 qstate->env->anchors->dlv_anchor->name)) { 2123 /* just like, there is no DLV */ 2124 verbose(VERB_ALGO, "ask above dlv repo"); 2125 vq->state = VAL_FINISHED_STATE; 2126 return 1; 2127 } 2128 if(vq->dlv_insecure_at && !dname_subdomain_c(vq->dlv_lookup_name, 2129 vq->dlv_insecure_at)) { 2130 /* already checked a chain lower than dlv_lookup_name */ 2131 verbose(VERB_ALGO, "ask above insecure endpoint"); 2132 log_nametypeclass(VERB_ALGO, "enpt", vq->dlv_insecure_at, 0, 0); 2133 vq->state = VAL_FINISHED_STATE; 2134 return 1; 2135 } 2136 2137 /* check negative cache before making new request */ 2138 if(val_neg_dlvlookup(ve->neg_cache, vq->dlv_lookup_name, 2139 vq->dlv_lookup_name_len, vq->qchase.qclass, 2140 qstate->env->rrset_cache, *qstate->env->now)) { 2141 /* does not exist, go up one (go higher). */ 2142 dname_remove_label(&vq->dlv_lookup_name, 2143 &vq->dlv_lookup_name_len); 2144 /* limit number of labels, limited number of recursion */ 2145 return processDLVLookup(qstate, vq, ve, id); 2146 } 2147 2148 if(!generate_request(qstate, id, vq->dlv_lookup_name, 2149 vq->dlv_lookup_name_len, LDNS_RR_TYPE_DLV, 2150 vq->qchase.qclass, 0)) { 2151 return val_error(qstate, id); 2152 } 2153 2154 return 0; 2155 } 2156 2157 /** 2158 * Handle validator state. 2159 * If a method returns true, the next state is started. If false, then 2160 * processing will stop. 2161 * @param qstate: query state. 2162 * @param vq: validator query state. 2163 * @param ve: validator shared global environment. 2164 * @param id: module id. 2165 */ 2166 static void 2167 val_handle(struct module_qstate* qstate, struct val_qstate* vq, 2168 struct val_env* ve, int id) 2169 { 2170 int cont = 1; 2171 while(cont) { 2172 verbose(VERB_ALGO, "val handle processing q with state %s", 2173 val_state_to_string(vq->state)); 2174 switch(vq->state) { 2175 case VAL_INIT_STATE: 2176 cont = processInit(qstate, vq, ve, id); 2177 break; 2178 case VAL_FINDKEY_STATE: 2179 cont = processFindKey(qstate, vq, id); 2180 break; 2181 case VAL_VALIDATE_STATE: 2182 cont = processValidate(qstate, vq, ve, id); 2183 break; 2184 case VAL_FINISHED_STATE: 2185 cont = processFinished(qstate, vq, ve, id); 2186 break; 2187 case VAL_DLVLOOKUP_STATE: 2188 cont = processDLVLookup(qstate, vq, ve, id); 2189 break; 2190 default: 2191 log_warn("validator: invalid state %d", 2192 vq->state); 2193 cont = 0; 2194 break; 2195 } 2196 } 2197 } 2198 2199 void 2200 val_operate(struct module_qstate* qstate, enum module_ev event, int id, 2201 struct outbound_entry* outbound) 2202 { 2203 struct val_env* ve = (struct val_env*)qstate->env->modinfo[id]; 2204 struct val_qstate* vq = (struct val_qstate*)qstate->minfo[id]; 2205 verbose(VERB_QUERY, "validator[module %d] operate: extstate:%s " 2206 "event:%s", id, strextstate(qstate->ext_state[id]), 2207 strmodulevent(event)); 2208 log_query_info(VERB_QUERY, "validator operate: query", 2209 &qstate->qinfo); 2210 if(vq && qstate->qinfo.qname != vq->qchase.qname) 2211 log_query_info(VERB_QUERY, "validator operate: chased to", 2212 &vq->qchase); 2213 (void)outbound; 2214 if(event == module_event_new || 2215 (event == module_event_pass && vq == NULL)) { 2216 /* pass request to next module, to get it */ 2217 verbose(VERB_ALGO, "validator: pass to next module"); 2218 qstate->ext_state[id] = module_wait_module; 2219 return; 2220 } 2221 if(event == module_event_moddone) { 2222 /* check if validation is needed */ 2223 verbose(VERB_ALGO, "validator: nextmodule returned"); 2224 if(!needs_validation(qstate, qstate->return_rcode, 2225 qstate->return_msg)) { 2226 /* no need to validate this */ 2227 if(qstate->return_msg) 2228 qstate->return_msg->rep->security = 2229 sec_status_indeterminate; 2230 qstate->ext_state[id] = module_finished; 2231 return; 2232 } 2233 if(already_validated(qstate->return_msg)) { 2234 qstate->ext_state[id] = module_finished; 2235 return; 2236 } 2237 /* qclass ANY should have validation result from spawned 2238 * queries. If we get here, it is bogus or an internal error */ 2239 if(qstate->qinfo.qclass == LDNS_RR_CLASS_ANY) { 2240 verbose(VERB_ALGO, "cannot validate classANY: bogus"); 2241 if(qstate->return_msg) 2242 qstate->return_msg->rep->security = 2243 sec_status_bogus; 2244 qstate->ext_state[id] = module_finished; 2245 return; 2246 } 2247 /* create state to start validation */ 2248 qstate->ext_state[id] = module_error; /* override this */ 2249 if(!vq) { 2250 vq = val_new(qstate, id); 2251 if(!vq) { 2252 log_err("validator: malloc failure"); 2253 qstate->ext_state[id] = module_error; 2254 return; 2255 } 2256 } else if(!vq->orig_msg) { 2257 if(!val_new_getmsg(qstate, vq)) { 2258 log_err("validator: malloc failure"); 2259 qstate->ext_state[id] = module_error; 2260 return; 2261 } 2262 } 2263 val_handle(qstate, vq, ve, id); 2264 return; 2265 } 2266 if(event == module_event_pass) { 2267 qstate->ext_state[id] = module_error; /* override this */ 2268 /* continue processing, since val_env exists */ 2269 val_handle(qstate, vq, ve, id); 2270 return; 2271 } 2272 log_err("validator: bad event %s", strmodulevent(event)); 2273 qstate->ext_state[id] = module_error; 2274 return; 2275 } 2276 2277 /** 2278 * Evaluate the response to a priming request. 2279 * 2280 * @param dnskey_rrset: DNSKEY rrset (can be NULL if none) in prime reply. 2281 * (this rrset is allocated in the wrong region, not the qstate). 2282 * @param ta: trust anchor. 2283 * @param qstate: qstate that needs key. 2284 * @param id: module id. 2285 * @return new key entry or NULL on allocation failure. 2286 * The key entry will either contain a validated DNSKEY rrset, or 2287 * represent a Null key (query failed, but validation did not), or a 2288 * Bad key (validation failed). 2289 */ 2290 static struct key_entry_key* 2291 primeResponseToKE(struct ub_packed_rrset_key* dnskey_rrset, 2292 struct trust_anchor* ta, struct module_qstate* qstate, int id) 2293 { 2294 struct val_env* ve = (struct val_env*)qstate->env->modinfo[id]; 2295 struct key_entry_key* kkey = NULL; 2296 enum sec_status sec = sec_status_unchecked; 2297 char* reason = NULL; 2298 int downprot = 1; 2299 2300 if(!dnskey_rrset) { 2301 log_nametypeclass(VERB_OPS, "failed to prime trust anchor -- " 2302 "could not fetch DNSKEY rrset", 2303 ta->name, LDNS_RR_TYPE_DNSKEY, ta->dclass); 2304 if(qstate->env->cfg->harden_dnssec_stripped) { 2305 errinf(qstate, "no DNSKEY rrset"); 2306 kkey = key_entry_create_bad(qstate->region, ta->name, 2307 ta->namelen, ta->dclass, BOGUS_KEY_TTL, 2308 *qstate->env->now); 2309 } else kkey = key_entry_create_null(qstate->region, ta->name, 2310 ta->namelen, ta->dclass, NULL_KEY_TTL, 2311 *qstate->env->now); 2312 if(!kkey) { 2313 log_err("out of memory: allocate fail prime key"); 2314 return NULL; 2315 } 2316 return kkey; 2317 } 2318 /* attempt to verify with trust anchor DS and DNSKEY */ 2319 kkey = val_verify_new_DNSKEYs_with_ta(qstate->region, qstate->env, ve, 2320 dnskey_rrset, ta->ds_rrset, ta->dnskey_rrset, downprot, 2321 &reason); 2322 if(!kkey) { 2323 log_err("out of memory: verifying prime TA"); 2324 return NULL; 2325 } 2326 if(key_entry_isgood(kkey)) 2327 sec = sec_status_secure; 2328 else 2329 sec = sec_status_bogus; 2330 verbose(VERB_DETAIL, "validate keys with anchor(DS): %s", 2331 sec_status_to_string(sec)); 2332 2333 if(sec != sec_status_secure) { 2334 log_nametypeclass(VERB_OPS, "failed to prime trust anchor -- " 2335 "DNSKEY rrset is not secure", 2336 ta->name, LDNS_RR_TYPE_DNSKEY, ta->dclass); 2337 /* NOTE: in this case, we should probably reject the trust 2338 * anchor for longer, perhaps forever. */ 2339 if(qstate->env->cfg->harden_dnssec_stripped) { 2340 errinf(qstate, reason); 2341 kkey = key_entry_create_bad(qstate->region, ta->name, 2342 ta->namelen, ta->dclass, BOGUS_KEY_TTL, 2343 *qstate->env->now); 2344 } else kkey = key_entry_create_null(qstate->region, ta->name, 2345 ta->namelen, ta->dclass, NULL_KEY_TTL, 2346 *qstate->env->now); 2347 if(!kkey) { 2348 log_err("out of memory: allocate null prime key"); 2349 return NULL; 2350 } 2351 return kkey; 2352 } 2353 2354 log_nametypeclass(VERB_DETAIL, "Successfully primed trust anchor", 2355 ta->name, LDNS_RR_TYPE_DNSKEY, ta->dclass); 2356 return kkey; 2357 } 2358 2359 /** 2360 * In inform supers, with the resulting message and rcode and the current 2361 * keyset in the super state, validate the DS response, returning a KeyEntry. 2362 * 2363 * @param qstate: query state that is validating and asked for a DS. 2364 * @param vq: validator query state 2365 * @param id: module id. 2366 * @param rcode: rcode result value. 2367 * @param msg: result message (if rcode is OK). 2368 * @param qinfo: from the sub query state, query info. 2369 * @param ke: the key entry to return. It returns 2370 * is_bad if the DS response fails to validate, is_null if the 2371 * DS response indicated an end to secure space, is_good if the DS 2372 * validated. It returns ke=NULL if the DS response indicated that the 2373 * request wasn't a delegation point. 2374 * @return 0 on servfail error (malloc failure). 2375 */ 2376 static int 2377 ds_response_to_ke(struct module_qstate* qstate, struct val_qstate* vq, 2378 int id, int rcode, struct dns_msg* msg, struct query_info* qinfo, 2379 struct key_entry_key** ke) 2380 { 2381 struct val_env* ve = (struct val_env*)qstate->env->modinfo[id]; 2382 char* reason = NULL; 2383 enum val_classification subtype; 2384 if(rcode != LDNS_RCODE_NOERROR) { 2385 char rc[16]; 2386 rc[0]=0; 2387 (void)sldns_wire2str_rcode_buf(rcode, rc, sizeof(rc)); 2388 /* errors here pretty much break validation */ 2389 verbose(VERB_DETAIL, "DS response was error, thus bogus"); 2390 errinf(qstate, rc); 2391 errinf(qstate, "no DS"); 2392 goto return_bogus; 2393 } 2394 2395 subtype = val_classify_response(BIT_RD, qinfo, qinfo, msg->rep, 0); 2396 if(subtype == VAL_CLASS_POSITIVE) { 2397 struct ub_packed_rrset_key* ds; 2398 enum sec_status sec; 2399 ds = reply_find_answer_rrset(qinfo, msg->rep); 2400 /* If there was no DS rrset, then we have mis-classified 2401 * this message. */ 2402 if(!ds) { 2403 log_warn("internal error: POSITIVE DS response was " 2404 "missing DS."); 2405 errinf(qstate, "no DS record"); 2406 goto return_bogus; 2407 } 2408 /* Verify only returns BOGUS or SECURE. If the rrset is 2409 * bogus, then we are done. */ 2410 sec = val_verify_rrset_entry(qstate->env, ve, ds, 2411 vq->key_entry, &reason); 2412 if(sec != sec_status_secure) { 2413 verbose(VERB_DETAIL, "DS rrset in DS response did " 2414 "not verify"); 2415 errinf(qstate, reason); 2416 goto return_bogus; 2417 } 2418 2419 /* If the DS rrset validates, we still have to make sure 2420 * that they are usable. */ 2421 if(!val_dsset_isusable(ds)) { 2422 /* If they aren't usable, then we treat it like 2423 * there was no DS. */ 2424 *ke = key_entry_create_null(qstate->region, 2425 qinfo->qname, qinfo->qname_len, qinfo->qclass, 2426 ub_packed_rrset_ttl(ds), *qstate->env->now); 2427 return (*ke) != NULL; 2428 } 2429 2430 /* Otherwise, we return the positive response. */ 2431 log_query_info(VERB_DETAIL, "validated DS", qinfo); 2432 *ke = key_entry_create_rrset(qstate->region, 2433 qinfo->qname, qinfo->qname_len, qinfo->qclass, ds, 2434 NULL, *qstate->env->now); 2435 return (*ke) != NULL; 2436 } else if(subtype == VAL_CLASS_NODATA || 2437 subtype == VAL_CLASS_NAMEERROR) { 2438 /* NODATA means that the qname exists, but that there was 2439 * no DS. This is a pretty normal case. */ 2440 time_t proof_ttl = 0; 2441 enum sec_status sec; 2442 2443 /* make sure there are NSECs or NSEC3s with signatures */ 2444 if(!val_has_signed_nsecs(msg->rep, &reason)) { 2445 verbose(VERB_ALGO, "no NSECs: %s", reason); 2446 errinf(qstate, reason); 2447 goto return_bogus; 2448 } 2449 2450 /* For subtype Name Error. 2451 * attempt ANS 2.8.1.0 compatibility where it sets rcode 2452 * to nxdomain, but really this is an Nodata/Noerror response. 2453 * Find and prove the empty nonterminal in that case */ 2454 2455 /* Try to prove absence of the DS with NSEC */ 2456 sec = val_nsec_prove_nodata_dsreply( 2457 qstate->env, ve, qinfo, msg->rep, vq->key_entry, 2458 &proof_ttl, &reason); 2459 switch(sec) { 2460 case sec_status_secure: 2461 verbose(VERB_DETAIL, "NSEC RRset for the " 2462 "referral proved no DS."); 2463 *ke = key_entry_create_null(qstate->region, 2464 qinfo->qname, qinfo->qname_len, 2465 qinfo->qclass, proof_ttl, 2466 *qstate->env->now); 2467 return (*ke) != NULL; 2468 case sec_status_insecure: 2469 verbose(VERB_DETAIL, "NSEC RRset for the " 2470 "referral proved not a delegation point"); 2471 *ke = NULL; 2472 return 1; 2473 case sec_status_bogus: 2474 verbose(VERB_DETAIL, "NSEC RRset for the " 2475 "referral did not prove no DS."); 2476 errinf(qstate, reason); 2477 goto return_bogus; 2478 case sec_status_unchecked: 2479 default: 2480 /* NSEC proof did not work, try next */ 2481 break; 2482 } 2483 2484 sec = nsec3_prove_nods(qstate->env, ve, 2485 msg->rep->rrsets + msg->rep->an_numrrsets, 2486 msg->rep->ns_numrrsets, qinfo, vq->key_entry, &reason); 2487 switch(sec) { 2488 case sec_status_insecure: 2489 /* case insecure also continues to unsigned 2490 * space. If nsec3-iter-count too high or 2491 * optout, then treat below as unsigned */ 2492 case sec_status_secure: 2493 verbose(VERB_DETAIL, "NSEC3s for the " 2494 "referral proved no DS."); 2495 *ke = key_entry_create_null(qstate->region, 2496 qinfo->qname, qinfo->qname_len, 2497 qinfo->qclass, proof_ttl, 2498 *qstate->env->now); 2499 return (*ke) != NULL; 2500 case sec_status_indeterminate: 2501 verbose(VERB_DETAIL, "NSEC3s for the " 2502 "referral proved no delegation"); 2503 *ke = NULL; 2504 return 1; 2505 case sec_status_bogus: 2506 verbose(VERB_DETAIL, "NSEC3s for the " 2507 "referral did not prove no DS."); 2508 errinf(qstate, reason); 2509 goto return_bogus; 2510 case sec_status_unchecked: 2511 default: 2512 /* NSEC3 proof did not work */ 2513 break; 2514 } 2515 2516 /* Apparently, no available NSEC/NSEC3 proved NODATA, so 2517 * this is BOGUS. */ 2518 verbose(VERB_DETAIL, "DS %s ran out of options, so return " 2519 "bogus", val_classification_to_string(subtype)); 2520 errinf(qstate, "no DS but also no proof of that"); 2521 goto return_bogus; 2522 } else if(subtype == VAL_CLASS_CNAME || 2523 subtype == VAL_CLASS_CNAMENOANSWER) { 2524 /* if the CNAME matches the exact name we want and is signed 2525 * properly, then also, we are sure that no DS exists there, 2526 * much like a NODATA proof */ 2527 enum sec_status sec; 2528 struct ub_packed_rrset_key* cname; 2529 cname = reply_find_rrset_section_an(msg->rep, qinfo->qname, 2530 qinfo->qname_len, LDNS_RR_TYPE_CNAME, qinfo->qclass); 2531 if(!cname) { 2532 errinf(qstate, "validator classified CNAME but no " 2533 "CNAME of the queried name for DS"); 2534 goto return_bogus; 2535 } 2536 if(((struct packed_rrset_data*)cname->entry.data)->rrsig_count 2537 == 0) { 2538 if(msg->rep->an_numrrsets != 0 && ntohs(msg->rep-> 2539 rrsets[0]->rk.type)==LDNS_RR_TYPE_DNAME) { 2540 errinf(qstate, "DS got DNAME answer"); 2541 } else { 2542 errinf(qstate, "DS got unsigned CNAME answer"); 2543 } 2544 goto return_bogus; 2545 } 2546 sec = val_verify_rrset_entry(qstate->env, ve, cname, 2547 vq->key_entry, &reason); 2548 if(sec == sec_status_secure) { 2549 verbose(VERB_ALGO, "CNAME validated, " 2550 "proof that DS does not exist"); 2551 /* and that it is not a referral point */ 2552 *ke = NULL; 2553 return 1; 2554 } 2555 errinf(qstate, "CNAME in DS response was not secure."); 2556 errinf(qstate, reason); 2557 goto return_bogus; 2558 } else { 2559 verbose(VERB_QUERY, "Encountered an unhandled type of " 2560 "DS response, thus bogus."); 2561 errinf(qstate, "no DS and"); 2562 if(FLAGS_GET_RCODE(msg->rep->flags) != LDNS_RCODE_NOERROR) { 2563 char rc[16]; 2564 rc[0]=0; 2565 (void)sldns_wire2str_rcode_buf((int)FLAGS_GET_RCODE( 2566 msg->rep->flags), rc, sizeof(rc)); 2567 errinf(qstate, rc); 2568 } else errinf(qstate, val_classification_to_string(subtype)); 2569 errinf(qstate, "message fails to prove that"); 2570 goto return_bogus; 2571 } 2572 return_bogus: 2573 *ke = key_entry_create_bad(qstate->region, qinfo->qname, 2574 qinfo->qname_len, qinfo->qclass, 2575 BOGUS_KEY_TTL, *qstate->env->now); 2576 return (*ke) != NULL; 2577 } 2578 2579 /** 2580 * Process DS response. Called from inform_supers. 2581 * Because it is in inform_supers, the mesh itself is busy doing callbacks 2582 * for a state that is to be deleted soon; don't touch the mesh; instead 2583 * set a state in the super, as the super will be reactivated soon. 2584 * Perform processing to determine what state to set in the super. 2585 * 2586 * @param qstate: query state that is validating and asked for a DS. 2587 * @param vq: validator query state 2588 * @param id: module id. 2589 * @param rcode: rcode result value. 2590 * @param msg: result message (if rcode is OK). 2591 * @param qinfo: from the sub query state, query info. 2592 * @param origin: the origin of msg. 2593 */ 2594 static void 2595 process_ds_response(struct module_qstate* qstate, struct val_qstate* vq, 2596 int id, int rcode, struct dns_msg* msg, struct query_info* qinfo, 2597 struct sock_list* origin) 2598 { 2599 struct key_entry_key* dske = NULL; 2600 uint8_t* olds = vq->empty_DS_name; 2601 vq->empty_DS_name = NULL; 2602 if(!ds_response_to_ke(qstate, vq, id, rcode, msg, qinfo, &dske)) { 2603 log_err("malloc failure in process_ds_response"); 2604 vq->key_entry = NULL; /* make it error */ 2605 vq->state = VAL_VALIDATE_STATE; 2606 return; 2607 } 2608 if(dske == NULL) { 2609 vq->empty_DS_name = regional_alloc_init(qstate->region, 2610 qinfo->qname, qinfo->qname_len); 2611 if(!vq->empty_DS_name) { 2612 log_err("malloc failure in empty_DS_name"); 2613 vq->key_entry = NULL; /* make it error */ 2614 vq->state = VAL_VALIDATE_STATE; 2615 return; 2616 } 2617 vq->empty_DS_len = qinfo->qname_len; 2618 vq->chain_blacklist = NULL; 2619 /* ds response indicated that we aren't on a delegation point. 2620 * Keep the forState.state on FINDKEY. */ 2621 } else if(key_entry_isgood(dske)) { 2622 vq->ds_rrset = key_entry_get_rrset(dske, qstate->region); 2623 if(!vq->ds_rrset) { 2624 log_err("malloc failure in process DS"); 2625 vq->key_entry = NULL; /* make it error */ 2626 vq->state = VAL_VALIDATE_STATE; 2627 return; 2628 } 2629 vq->chain_blacklist = NULL; /* fresh blacklist for next part*/ 2630 /* Keep the forState.state on FINDKEY. */ 2631 } else if(key_entry_isbad(dske) 2632 && vq->restart_count < VAL_MAX_RESTART_COUNT) { 2633 vq->empty_DS_name = olds; 2634 val_blacklist(&vq->chain_blacklist, qstate->region, origin, 1); 2635 qstate->errinf = NULL; 2636 vq->restart_count++; 2637 } else { 2638 if(key_entry_isbad(dske)) { 2639 errinf_origin(qstate, origin); 2640 errinf_dname(qstate, "for DS", qinfo->qname); 2641 } 2642 /* NOTE: the reason for the DS to be not good (that is, 2643 * either bad or null) should have been logged by 2644 * dsResponseToKE. */ 2645 vq->key_entry = dske; 2646 /* The FINDKEY phase has ended, so move on. */ 2647 vq->state = VAL_VALIDATE_STATE; 2648 } 2649 } 2650 2651 /** 2652 * Process DNSKEY response. Called from inform_supers. 2653 * Sets the key entry in the state. 2654 * Because it is in inform_supers, the mesh itself is busy doing callbacks 2655 * for a state that is to be deleted soon; don't touch the mesh; instead 2656 * set a state in the super, as the super will be reactivated soon. 2657 * Perform processing to determine what state to set in the super. 2658 * 2659 * @param qstate: query state that is validating and asked for a DNSKEY. 2660 * @param vq: validator query state 2661 * @param id: module id. 2662 * @param rcode: rcode result value. 2663 * @param msg: result message (if rcode is OK). 2664 * @param qinfo: from the sub query state, query info. 2665 * @param origin: the origin of msg. 2666 */ 2667 static void 2668 process_dnskey_response(struct module_qstate* qstate, struct val_qstate* vq, 2669 int id, int rcode, struct dns_msg* msg, struct query_info* qinfo, 2670 struct sock_list* origin) 2671 { 2672 struct val_env* ve = (struct val_env*)qstate->env->modinfo[id]; 2673 struct key_entry_key* old = vq->key_entry; 2674 struct ub_packed_rrset_key* dnskey = NULL; 2675 int downprot; 2676 char* reason = NULL; 2677 2678 if(rcode == LDNS_RCODE_NOERROR) 2679 dnskey = reply_find_answer_rrset(qinfo, msg->rep); 2680 2681 if(dnskey == NULL) { 2682 /* bad response */ 2683 verbose(VERB_DETAIL, "Missing DNSKEY RRset in response to " 2684 "DNSKEY query."); 2685 if(vq->restart_count < VAL_MAX_RESTART_COUNT) { 2686 val_blacklist(&vq->chain_blacklist, qstate->region, 2687 origin, 1); 2688 qstate->errinf = NULL; 2689 vq->restart_count++; 2690 return; 2691 } 2692 vq->key_entry = key_entry_create_bad(qstate->region, 2693 qinfo->qname, qinfo->qname_len, qinfo->qclass, 2694 BOGUS_KEY_TTL, *qstate->env->now); 2695 if(!vq->key_entry) { 2696 log_err("alloc failure in missing dnskey response"); 2697 /* key_entry is NULL for failure in Validate */ 2698 } 2699 errinf(qstate, "No DNSKEY record"); 2700 errinf_origin(qstate, origin); 2701 errinf_dname(qstate, "for key", qinfo->qname); 2702 vq->state = VAL_VALIDATE_STATE; 2703 return; 2704 } 2705 if(!vq->ds_rrset) { 2706 log_err("internal error: no DS rrset for new DNSKEY response"); 2707 vq->key_entry = NULL; 2708 vq->state = VAL_VALIDATE_STATE; 2709 return; 2710 } 2711 downprot = 1; 2712 vq->key_entry = val_verify_new_DNSKEYs(qstate->region, qstate->env, 2713 ve, dnskey, vq->ds_rrset, downprot, &reason); 2714 2715 if(!vq->key_entry) { 2716 log_err("out of memory in verify new DNSKEYs"); 2717 vq->state = VAL_VALIDATE_STATE; 2718 return; 2719 } 2720 /* If the key entry isBad or isNull, then we can move on to the next 2721 * state. */ 2722 if(!key_entry_isgood(vq->key_entry)) { 2723 if(key_entry_isbad(vq->key_entry)) { 2724 if(vq->restart_count < VAL_MAX_RESTART_COUNT) { 2725 val_blacklist(&vq->chain_blacklist, 2726 qstate->region, origin, 1); 2727 qstate->errinf = NULL; 2728 vq->restart_count++; 2729 vq->key_entry = old; 2730 return; 2731 } 2732 verbose(VERB_DETAIL, "Did not match a DS to a DNSKEY, " 2733 "thus bogus."); 2734 errinf(qstate, reason); 2735 errinf_origin(qstate, origin); 2736 errinf_dname(qstate, "for key", qinfo->qname); 2737 } 2738 vq->chain_blacklist = NULL; 2739 vq->state = VAL_VALIDATE_STATE; 2740 return; 2741 } 2742 vq->chain_blacklist = NULL; 2743 qstate->errinf = NULL; 2744 2745 /* The DNSKEY validated, so cache it as a trusted key rrset. */ 2746 key_cache_insert(ve->kcache, vq->key_entry, qstate); 2747 2748 /* If good, we stay in the FINDKEY state. */ 2749 log_query_info(VERB_DETAIL, "validated DNSKEY", qinfo); 2750 } 2751 2752 /** 2753 * Process prime response 2754 * Sets the key entry in the state. 2755 * 2756 * @param qstate: query state that is validating and primed a trust anchor. 2757 * @param vq: validator query state 2758 * @param id: module id. 2759 * @param rcode: rcode result value. 2760 * @param msg: result message (if rcode is OK). 2761 * @param origin: the origin of msg. 2762 */ 2763 static void 2764 process_prime_response(struct module_qstate* qstate, struct val_qstate* vq, 2765 int id, int rcode, struct dns_msg* msg, struct sock_list* origin) 2766 { 2767 struct val_env* ve = (struct val_env*)qstate->env->modinfo[id]; 2768 struct ub_packed_rrset_key* dnskey_rrset = NULL; 2769 struct trust_anchor* ta = anchor_find(qstate->env->anchors, 2770 vq->trust_anchor_name, vq->trust_anchor_labs, 2771 vq->trust_anchor_len, vq->qchase.qclass); 2772 if(!ta) { 2773 /* trust anchor revoked, restart with less anchors */ 2774 vq->state = VAL_INIT_STATE; 2775 if(!vq->trust_anchor_name) 2776 vq->state = VAL_VALIDATE_STATE; /* break a loop */ 2777 vq->trust_anchor_name = NULL; 2778 return; 2779 } 2780 /* Fetch and validate the keyEntry that corresponds to the 2781 * current trust anchor. */ 2782 if(rcode == LDNS_RCODE_NOERROR) { 2783 dnskey_rrset = reply_find_rrset_section_an(msg->rep, 2784 ta->name, ta->namelen, LDNS_RR_TYPE_DNSKEY, 2785 ta->dclass); 2786 } 2787 if(ta->autr) { 2788 if(!autr_process_prime(qstate->env, ve, ta, dnskey_rrset)) { 2789 /* trust anchor revoked, restart with less anchors */ 2790 vq->state = VAL_INIT_STATE; 2791 vq->trust_anchor_name = NULL; 2792 return; 2793 } 2794 } 2795 vq->key_entry = primeResponseToKE(dnskey_rrset, ta, qstate, id); 2796 lock_basic_unlock(&ta->lock); 2797 if(vq->key_entry) { 2798 if(key_entry_isbad(vq->key_entry) 2799 && vq->restart_count < VAL_MAX_RESTART_COUNT) { 2800 val_blacklist(&vq->chain_blacklist, qstate->region, 2801 origin, 1); 2802 qstate->errinf = NULL; 2803 vq->restart_count++; 2804 vq->key_entry = NULL; 2805 vq->state = VAL_INIT_STATE; 2806 return; 2807 } 2808 vq->chain_blacklist = NULL; 2809 errinf_origin(qstate, origin); 2810 errinf_dname(qstate, "for trust anchor", ta->name); 2811 /* store the freshly primed entry in the cache */ 2812 key_cache_insert(ve->kcache, vq->key_entry, qstate); 2813 } 2814 2815 /* If the result of the prime is a null key, skip the FINDKEY state.*/ 2816 if(!vq->key_entry || key_entry_isnull(vq->key_entry) || 2817 key_entry_isbad(vq->key_entry)) { 2818 vq->state = VAL_VALIDATE_STATE; 2819 } 2820 /* the qstate will be reactivated after inform_super is done */ 2821 } 2822 2823 /** 2824 * Process DLV response. Called from inform_supers. 2825 * Because it is in inform_supers, the mesh itself is busy doing callbacks 2826 * for a state that is to be deleted soon; don't touch the mesh; instead 2827 * set a state in the super, as the super will be reactivated soon. 2828 * Perform processing to determine what state to set in the super. 2829 * 2830 * @param qstate: query state that is validating and asked for a DLV. 2831 * @param vq: validator query state 2832 * @param id: module id. 2833 * @param rcode: rcode result value. 2834 * @param msg: result message (if rcode is OK). 2835 * @param qinfo: from the sub query state, query info. 2836 */ 2837 static void 2838 process_dlv_response(struct module_qstate* qstate, struct val_qstate* vq, 2839 int id, int rcode, struct dns_msg* msg, struct query_info* qinfo) 2840 { 2841 struct val_env* ve = (struct val_env*)qstate->env->modinfo[id]; 2842 2843 verbose(VERB_ALGO, "process dlv response to super"); 2844 if(rcode != LDNS_RCODE_NOERROR) { 2845 /* lookup failed, set in vq to give up */ 2846 vq->dlv_status = dlv_error; 2847 verbose(VERB_ALGO, "response is error"); 2848 return; 2849 } 2850 if(msg->rep->security != sec_status_secure) { 2851 vq->dlv_status = dlv_error; 2852 verbose(VERB_ALGO, "response is not secure, %s", 2853 sec_status_to_string(msg->rep->security)); 2854 return; 2855 } 2856 /* was the lookup a success? validated DLV? */ 2857 if(FLAGS_GET_RCODE(msg->rep->flags) == LDNS_RCODE_NOERROR && 2858 msg->rep->an_numrrsets == 1 && 2859 msg->rep->security == sec_status_secure && 2860 ntohs(msg->rep->rrsets[0]->rk.type) == LDNS_RR_TYPE_DLV && 2861 ntohs(msg->rep->rrsets[0]->rk.rrset_class) == qinfo->qclass && 2862 query_dname_compare(msg->rep->rrsets[0]->rk.dname, 2863 vq->dlv_lookup_name) == 0) { 2864 /* yay! it is just like a DS */ 2865 vq->ds_rrset = (struct ub_packed_rrset_key*) 2866 regional_alloc_init(qstate->region, 2867 msg->rep->rrsets[0], sizeof(*vq->ds_rrset)); 2868 if(!vq->ds_rrset) { 2869 log_err("out of memory in process_dlv"); 2870 return; 2871 } 2872 vq->ds_rrset->entry.key = vq->ds_rrset; 2873 vq->ds_rrset->rk.dname = (uint8_t*)regional_alloc_init( 2874 qstate->region, vq->ds_rrset->rk.dname, 2875 vq->ds_rrset->rk.dname_len); 2876 if(!vq->ds_rrset->rk.dname) { 2877 log_err("out of memory in process_dlv"); 2878 vq->dlv_status = dlv_error; 2879 return; 2880 } 2881 vq->ds_rrset->entry.data = regional_alloc_init(qstate->region, 2882 vq->ds_rrset->entry.data, 2883 packed_rrset_sizeof(vq->ds_rrset->entry.data)); 2884 if(!vq->ds_rrset->entry.data) { 2885 log_err("out of memory in process_dlv"); 2886 vq->dlv_status = dlv_error; 2887 return; 2888 } 2889 packed_rrset_ptr_fixup(vq->ds_rrset->entry.data); 2890 /* make vq do a DNSKEY query next up */ 2891 vq->dlv_status = dlv_success; 2892 return; 2893 } 2894 /* store NSECs into negative cache */ 2895 val_neg_addreply(ve->neg_cache, msg->rep); 2896 2897 /* was the lookup a failure? 2898 * if we have to go up into the DLV for a higher DLV anchor 2899 * then set this in the vq, so it can make queries when activated. 2900 * See if the NSECs indicate that we should look for higher DLV 2901 * or, that there is no DLV securely */ 2902 if(!val_nsec_check_dlv(qinfo, msg->rep, &vq->dlv_lookup_name, 2903 &vq->dlv_lookup_name_len)) { 2904 vq->dlv_status = dlv_error; 2905 verbose(VERB_ALGO, "nsec error"); 2906 return; 2907 } 2908 if(!dname_subdomain_c(vq->dlv_lookup_name, 2909 qstate->env->anchors->dlv_anchor->name)) { 2910 vq->dlv_status = dlv_there_is_no_dlv; 2911 return; 2912 } 2913 vq->dlv_status = dlv_ask_higher; 2914 } 2915 2916 /* 2917 * inform validator super. 2918 * 2919 * @param qstate: query state that finished. 2920 * @param id: module id. 2921 * @param super: the qstate to inform. 2922 */ 2923 void 2924 val_inform_super(struct module_qstate* qstate, int id, 2925 struct module_qstate* super) 2926 { 2927 struct val_qstate* vq = (struct val_qstate*)super->minfo[id]; 2928 log_query_info(VERB_ALGO, "validator: inform_super, sub is", 2929 &qstate->qinfo); 2930 log_query_info(VERB_ALGO, "super is", &super->qinfo); 2931 if(!vq) { 2932 verbose(VERB_ALGO, "super: has no validator state"); 2933 return; 2934 } 2935 if(vq->wait_prime_ta) { 2936 vq->wait_prime_ta = 0; 2937 process_prime_response(super, vq, id, qstate->return_rcode, 2938 qstate->return_msg, qstate->reply_origin); 2939 return; 2940 } 2941 if(qstate->qinfo.qtype == LDNS_RR_TYPE_DS) { 2942 process_ds_response(super, vq, id, qstate->return_rcode, 2943 qstate->return_msg, &qstate->qinfo, 2944 qstate->reply_origin); 2945 return; 2946 } else if(qstate->qinfo.qtype == LDNS_RR_TYPE_DNSKEY) { 2947 process_dnskey_response(super, vq, id, qstate->return_rcode, 2948 qstate->return_msg, &qstate->qinfo, 2949 qstate->reply_origin); 2950 return; 2951 } else if(qstate->qinfo.qtype == LDNS_RR_TYPE_DLV) { 2952 process_dlv_response(super, vq, id, qstate->return_rcode, 2953 qstate->return_msg, &qstate->qinfo); 2954 return; 2955 } 2956 log_err("internal error in validator: no inform_supers possible"); 2957 } 2958 2959 void 2960 val_clear(struct module_qstate* qstate, int id) 2961 { 2962 if(!qstate) 2963 return; 2964 /* everything is allocated in the region, so assign NULL */ 2965 qstate->minfo[id] = NULL; 2966 } 2967 2968 size_t 2969 val_get_mem(struct module_env* env, int id) 2970 { 2971 struct val_env* ve = (struct val_env*)env->modinfo[id]; 2972 if(!ve) 2973 return 0; 2974 return sizeof(*ve) + key_cache_get_mem(ve->kcache) + 2975 val_neg_get_mem(ve->neg_cache) + 2976 sizeof(size_t)*2*ve->nsec3_keyiter_count; 2977 } 2978 2979 /** 2980 * The validator function block 2981 */ 2982 static struct module_func_block val_block = { 2983 "validator", 2984 &val_init, &val_deinit, &val_operate, &val_inform_super, &val_clear, 2985 &val_get_mem 2986 }; 2987 2988 struct module_func_block* 2989 val_get_funcblock(void) 2990 { 2991 return &val_block; 2992 } 2993 2994 const char* 2995 val_state_to_string(enum val_state state) 2996 { 2997 switch(state) { 2998 case VAL_INIT_STATE: return "VAL_INIT_STATE"; 2999 case VAL_FINDKEY_STATE: return "VAL_FINDKEY_STATE"; 3000 case VAL_VALIDATE_STATE: return "VAL_VALIDATE_STATE"; 3001 case VAL_FINISHED_STATE: return "VAL_FINISHED_STATE"; 3002 case VAL_DLVLOOKUP_STATE: return "VAL_DLVLOOKUP_STATE"; 3003 } 3004 return "UNKNOWN VALIDATOR STATE"; 3005 } 3006 3007