2 * iterator/iterator.c - iterative resolver DNS query response module
4 * Copyright (c) 2007, NLnet Labs. All rights reserved.
6 * This software is open source.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
12 * Redistributions of source code must retain the above copyright notice,
13 * this list of conditions and the following disclaimer.
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.
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.
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
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28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
39 * This file contains a module that performs recusive iterative DNS query
44 #include "iterator/iterator.h"
45 #include "iterator/iter_utils.h"
46 #include "iterator/iter_hints.h"
47 #include "iterator/iter_fwd.h"
48 #include "iterator/iter_donotq.h"
49 #include "iterator/iter_delegpt.h"
50 #include "iterator/iter_resptype.h"
51 #include "iterator/iter_scrub.h"
52 #include "iterator/iter_priv.h"
53 #include "validator/val_neg.h"
54 #include "services/cache/dns.h"
55 #include "services/cache/infra.h"
56 #include "util/module.h"
57 #include "util/netevent.h"
58 #include "util/net_help.h"
59 #include "util/regional.h"
60 #include "util/data/dname.h"
61 #include "util/data/msgencode.h"
62 #include "util/fptr_wlist.h"
63 #include "util/config_file.h"
64 #include "util/random.h"
65 #include "sldns/rrdef.h"
66 #include "sldns/wire2str.h"
67 #include "sldns/str2wire.h"
68 #include "sldns/parseutil.h"
69 #include "sldns/sbuffer.h"
72 iter_init(struct module_env* env, int id)
74 struct iter_env* iter_env = (struct iter_env*)calloc(1,
75 sizeof(struct iter_env));
77 log_err("malloc failure");
80 env->modinfo[id] = (void*)iter_env;
81 if(!iter_apply_cfg(iter_env, env->cfg)) {
82 log_err("iterator: could not apply configuration settings.");
85 if(env->cfg->qname_minimisation) {
86 uint8_t dname[LDNS_MAX_DOMAINLEN+1];
87 size_t len = sizeof(dname);
88 if(sldns_str2wire_dname_buf("ip6.arpa.", dname, &len) != 0) {
89 log_err("ip6.arpa. parse error");
92 iter_env->ip6arpa_dname = (uint8_t*)malloc(len);
93 if(!iter_env->ip6arpa_dname) {
94 log_err("malloc failure");
97 memcpy(iter_env->ip6arpa_dname, dname, len);
103 /** delete caps_whitelist element */
105 caps_free(struct rbnode_t* n, void* ATTR_UNUSED(d))
108 free(((struct name_tree_node*)n)->name);
114 iter_deinit(struct module_env* env, int id)
116 struct iter_env* iter_env;
117 if(!env || !env->modinfo[id])
119 iter_env = (struct iter_env*)env->modinfo[id];
120 free(iter_env->ip6arpa_dname);
121 free(iter_env->target_fetch_policy);
122 priv_delete(iter_env->priv);
123 donotq_delete(iter_env->donotq);
124 if(iter_env->caps_white) {
125 traverse_postorder(iter_env->caps_white, caps_free, NULL);
126 free(iter_env->caps_white);
129 env->modinfo[id] = NULL;
132 /** new query for iterator */
134 iter_new(struct module_qstate* qstate, int id)
136 struct iter_qstate* iq = (struct iter_qstate*)regional_alloc(
137 qstate->region, sizeof(struct iter_qstate));
138 qstate->minfo[id] = iq;
141 memset(iq, 0, sizeof(*iq));
142 iq->state = INIT_REQUEST_STATE;
143 iq->final_state = FINISHED_STATE;
144 iq->an_prepend_list = NULL;
145 iq->an_prepend_last = NULL;
146 iq->ns_prepend_list = NULL;
147 iq->ns_prepend_last = NULL;
150 iq->num_target_queries = 0;
151 iq->num_current_queries = 0;
152 iq->query_restart_count = 0;
153 iq->referral_count = 0;
155 iq->ratelimit_ok = 0;
156 iq->target_count = NULL;
157 iq->wait_priming_stub = 0;
158 iq->refetch_glue = 0;
159 iq->dnssec_expected = 0;
160 iq->dnssec_lame_query = 0;
161 iq->chase_flags = qstate->query_flags;
162 /* Start with the (current) qname. */
163 iq->qchase = qstate->qinfo;
164 outbound_list_init(&iq->outlist);
165 if (qstate->env->cfg->qname_minimisation)
166 iq->minimisation_state = INIT_MINIMISE_STATE;
168 iq->minimisation_state = DONOT_MINIMISE_STATE;
170 memset(&iq->qinfo_out, 0, sizeof(struct query_info));
175 * Transition to the next state. This can be used to advance a currently
176 * processing event. It cannot be used to reactivate a forEvent.
178 * @param iq: iterator query state
179 * @param nextstate The state to transition to.
180 * @return true. This is so this can be called as the return value for the
181 * actual process*State() methods. (Transitioning to the next state
182 * implies further processing).
185 next_state(struct iter_qstate* iq, enum iter_state nextstate)
187 /* If transitioning to a "response" state, make sure that there is a
189 if(iter_state_is_responsestate(nextstate)) {
190 if(iq->response == NULL) {
191 log_err("transitioning to response state sans "
195 iq->state = nextstate;
200 * Transition an event to its final state. Final states always either return
201 * a result up the module chain, or reactivate a dependent event. Which
202 * final state to transition to is set in the module state for the event when
203 * it was created, and depends on the original purpose of the event.
205 * The response is stored in the qstate->buf buffer.
207 * @param iq: iterator query state
208 * @return false. This is so this method can be used as the return value for
209 * the processState methods. (Transitioning to the final state
212 final_state(struct iter_qstate* iq)
214 return next_state(iq, iq->final_state);
218 * Callback routine to handle errors in parent query states
219 * @param qstate: query state that failed.
220 * @param id: module id.
221 * @param super: super state.
224 error_supers(struct module_qstate* qstate, int id, struct module_qstate* super)
226 struct iter_qstate* super_iq = (struct iter_qstate*)super->minfo[id];
228 if(qstate->qinfo.qtype == LDNS_RR_TYPE_A ||
229 qstate->qinfo.qtype == LDNS_RR_TYPE_AAAA) {
230 /* mark address as failed. */
231 struct delegpt_ns* dpns = NULL;
233 dpns = delegpt_find_ns(super_iq->dp,
234 qstate->qinfo.qname, qstate->qinfo.qname_len);
237 verbose(VERB_ALGO, "subq error, but not interested");
238 log_query_info(VERB_ALGO, "superq", &super->qinfo);
240 delegpt_log(VERB_ALGO, super_iq->dp);
244 /* see if the failure did get (parent-lame) info */
245 if(!cache_fill_missing(super->env,
246 super_iq->qchase.qclass, super->region,
248 log_err("out of memory adding missing");
250 dpns->resolved = 1; /* mark as failed */
251 super_iq->num_target_queries--;
253 if(qstate->qinfo.qtype == LDNS_RR_TYPE_NS) {
254 /* prime failed to get delegation */
257 /* evaluate targets again */
258 super_iq->state = QUERYTARGETS_STATE;
259 /* super becomes runnable, and will process this change */
263 * Return an error to the client
264 * @param qstate: our query state
265 * @param id: module id
266 * @param rcode: error code (DNS errcode).
267 * @return: 0 for use by caller, to make notation easy, like:
268 * return error_response(..).
271 error_response(struct module_qstate* qstate, int id, int rcode)
273 verbose(VERB_QUERY, "return error response %s",
274 sldns_lookup_by_id(sldns_rcodes, rcode)?
275 sldns_lookup_by_id(sldns_rcodes, rcode)->name:"??");
276 qstate->return_rcode = rcode;
277 qstate->return_msg = NULL;
278 qstate->ext_state[id] = module_finished;
283 * Return an error to the client and cache the error code in the
284 * message cache (so per qname, qtype, qclass).
285 * @param qstate: our query state
286 * @param id: module id
287 * @param rcode: error code (DNS errcode).
288 * @return: 0 for use by caller, to make notation easy, like:
289 * return error_response(..).
292 error_response_cache(struct module_qstate* qstate, int id, int rcode)
295 struct reply_info err;
296 if(qstate->prefetch_leeway > NORR_TTL) {
297 verbose(VERB_ALGO, "error response for prefetch in cache");
298 /* attempt to adjust the cache entry prefetch */
299 if(dns_cache_prefetch_adjust(qstate->env, &qstate->qinfo,
300 NORR_TTL, qstate->query_flags))
301 return error_response(qstate, id, rcode);
302 /* if that fails (not in cache), fall through to store err */
304 memset(&err, 0, sizeof(err));
305 err.flags = (uint16_t)(BIT_QR | BIT_RA);
306 FLAGS_SET_RCODE(err.flags, rcode);
309 err.prefetch_ttl = PREFETCH_TTL_CALC(err.ttl);
310 /* do not waste time trying to validate this servfail */
311 err.security = sec_status_indeterminate;
312 verbose(VERB_ALGO, "store error response in message cache");
313 iter_dns_store(qstate->env, &qstate->qinfo, &err, 0, 0, 0, NULL,
314 qstate->query_flags);
315 return error_response(qstate, id, rcode);
318 /** check if prepend item is duplicate item */
320 prepend_is_duplicate(struct ub_packed_rrset_key** sets, size_t to,
321 struct ub_packed_rrset_key* dup)
324 for(i=0; i<to; i++) {
325 if(sets[i]->rk.type == dup->rk.type &&
326 sets[i]->rk.rrset_class == dup->rk.rrset_class &&
327 sets[i]->rk.dname_len == dup->rk.dname_len &&
328 query_dname_compare(sets[i]->rk.dname, dup->rk.dname)
335 /** prepend the prepend list in the answer and authority section of dns_msg */
337 iter_prepend(struct iter_qstate* iq, struct dns_msg* msg,
338 struct regional* region)
340 struct iter_prep_list* p;
341 struct ub_packed_rrset_key** sets;
342 size_t num_an = 0, num_ns = 0;;
343 for(p = iq->an_prepend_list; p; p = p->next)
345 for(p = iq->ns_prepend_list; p; p = p->next)
347 if(num_an + num_ns == 0)
349 verbose(VERB_ALGO, "prepending %d rrsets", (int)num_an + (int)num_ns);
350 if(num_an > RR_COUNT_MAX || num_ns > RR_COUNT_MAX ||
351 msg->rep->rrset_count > RR_COUNT_MAX) return 0; /* overflow */
352 sets = regional_alloc(region, (num_an+num_ns+msg->rep->rrset_count) *
353 sizeof(struct ub_packed_rrset_key*));
358 for(p = iq->an_prepend_list; p; p = p->next) {
359 sets[num_an++] = p->rrset;
361 memcpy(sets+num_an, msg->rep->rrsets, msg->rep->an_numrrsets *
362 sizeof(struct ub_packed_rrset_key*));
365 for(p = iq->ns_prepend_list; p; p = p->next) {
366 if(prepend_is_duplicate(sets+msg->rep->an_numrrsets+num_an,
367 num_ns, p->rrset) || prepend_is_duplicate(
368 msg->rep->rrsets+msg->rep->an_numrrsets,
369 msg->rep->ns_numrrsets, p->rrset))
371 sets[msg->rep->an_numrrsets + num_an + num_ns++] = p->rrset;
373 memcpy(sets + num_an + msg->rep->an_numrrsets + num_ns,
374 msg->rep->rrsets + msg->rep->an_numrrsets,
375 (msg->rep->ns_numrrsets + msg->rep->ar_numrrsets) *
376 sizeof(struct ub_packed_rrset_key*));
378 /* NXDOMAIN rcode can stay if we prepended DNAME/CNAMEs, because
379 * this is what recursors should give. */
380 msg->rep->rrset_count += num_an + num_ns;
381 msg->rep->an_numrrsets += num_an;
382 msg->rep->ns_numrrsets += num_ns;
383 msg->rep->rrsets = sets;
388 * Add rrset to ANSWER prepend list
389 * @param qstate: query state.
390 * @param iq: iterator query state.
391 * @param rrset: rrset to add.
392 * @return false on failure (malloc).
395 iter_add_prepend_answer(struct module_qstate* qstate, struct iter_qstate* iq,
396 struct ub_packed_rrset_key* rrset)
398 struct iter_prep_list* p = (struct iter_prep_list*)regional_alloc(
399 qstate->region, sizeof(struct iter_prep_list));
405 if(iq->an_prepend_last)
406 iq->an_prepend_last->next = p;
407 else iq->an_prepend_list = p;
408 iq->an_prepend_last = p;
413 * Add rrset to AUTHORITY prepend list
414 * @param qstate: query state.
415 * @param iq: iterator query state.
416 * @param rrset: rrset to add.
417 * @return false on failure (malloc).
420 iter_add_prepend_auth(struct module_qstate* qstate, struct iter_qstate* iq,
421 struct ub_packed_rrset_key* rrset)
423 struct iter_prep_list* p = (struct iter_prep_list*)regional_alloc(
424 qstate->region, sizeof(struct iter_prep_list));
430 if(iq->ns_prepend_last)
431 iq->ns_prepend_last->next = p;
432 else iq->ns_prepend_list = p;
433 iq->ns_prepend_last = p;
438 * Given a CNAME response (defined as a response containing a CNAME or DNAME
439 * that does not answer the request), process the response, modifying the
440 * state as necessary. This follows the CNAME/DNAME chain and returns the
443 * sets the new query name, after following the CNAME/DNAME chain.
444 * @param qstate: query state.
445 * @param iq: iterator query state.
446 * @param msg: the response.
447 * @param mname: returned target new query name.
448 * @param mname_len: length of mname.
449 * @return false on (malloc) error.
452 handle_cname_response(struct module_qstate* qstate, struct iter_qstate* iq,
453 struct dns_msg* msg, uint8_t** mname, size_t* mname_len)
456 /* Start with the (current) qname. */
457 *mname = iq->qchase.qname;
458 *mname_len = iq->qchase.qname_len;
460 /* Iterate over the ANSWER rrsets in order, looking for CNAMEs and
462 for(i=0; i<msg->rep->an_numrrsets; i++) {
463 struct ub_packed_rrset_key* r = msg->rep->rrsets[i];
464 /* If there is a (relevant) DNAME, add it to the list.
465 * We always expect there to be CNAME that was generated
466 * by this DNAME following, so we don't process the DNAME
468 if(ntohs(r->rk.type) == LDNS_RR_TYPE_DNAME &&
469 dname_strict_subdomain_c(*mname, r->rk.dname)) {
470 if(!iter_add_prepend_answer(qstate, iq, r))
475 if(ntohs(r->rk.type) == LDNS_RR_TYPE_CNAME &&
476 query_dname_compare(*mname, r->rk.dname) == 0) {
477 /* Add this relevant CNAME rrset to the prepend list.*/
478 if(!iter_add_prepend_answer(qstate, iq, r))
480 get_cname_target(r, mname, mname_len);
483 /* Other rrsets in the section are ignored. */
485 /* add authority rrsets to authority prepend, for wildcarded CNAMEs */
486 for(i=msg->rep->an_numrrsets; i<msg->rep->an_numrrsets +
487 msg->rep->ns_numrrsets; i++) {
488 struct ub_packed_rrset_key* r = msg->rep->rrsets[i];
489 /* only add NSEC/NSEC3, as they may be needed for validation */
490 if(ntohs(r->rk.type) == LDNS_RR_TYPE_NSEC ||
491 ntohs(r->rk.type) == LDNS_RR_TYPE_NSEC3) {
492 if(!iter_add_prepend_auth(qstate, iq, r))
499 /** see if target name is caps-for-id whitelisted */
501 is_caps_whitelisted(struct iter_env* ie, struct iter_qstate* iq)
503 if(!ie->caps_white) return 0; /* no whitelist, or no capsforid */
504 return name_tree_lookup(ie->caps_white, iq->qchase.qname,
505 iq->qchase.qname_len, dname_count_labels(iq->qchase.qname),
506 iq->qchase.qclass) != NULL;
509 /** create target count structure for this query */
511 target_count_create(struct iter_qstate* iq)
513 if(!iq->target_count) {
514 iq->target_count = (int*)calloc(2, sizeof(int));
515 /* if calloc fails we simply do not track this number */
517 iq->target_count[0] = 1;
522 target_count_increase(struct iter_qstate* iq, int num)
524 target_count_create(iq);
526 iq->target_count[1] += num;
530 * Generate a subrequest.
531 * Generate a local request event. Local events are tied to this module, and
532 * have a corresponding (first tier) event that is waiting for this event to
533 * resolve to continue.
535 * @param qname The query name for this request.
536 * @param qnamelen length of qname
537 * @param qtype The query type for this request.
538 * @param qclass The query class for this request.
539 * @param qstate The event that is generating this event.
540 * @param id: module id.
541 * @param iq: The iterator state that is generating this event.
542 * @param initial_state The initial response state (normally this
543 * is QUERY_RESP_STATE, unless it is known that the request won't
544 * need iterative processing
545 * @param finalstate The final state for the response to this request.
546 * @param subq_ret: if newly allocated, the subquerystate, or NULL if it does
547 * not need initialisation.
548 * @param v: if true, validation is done on the subquery.
549 * @return false on error (malloc).
552 generate_sub_request(uint8_t* qname, size_t qnamelen, uint16_t qtype,
553 uint16_t qclass, struct module_qstate* qstate, int id,
554 struct iter_qstate* iq, enum iter_state initial_state,
555 enum iter_state finalstate, struct module_qstate** subq_ret, int v)
557 struct module_qstate* subq = NULL;
558 struct iter_qstate* subiq = NULL;
559 uint16_t qflags = 0; /* OPCODE QUERY, no flags */
560 struct query_info qinf;
561 int prime = (finalstate == PRIME_RESP_STATE)?1:0;
564 qinf.qname_len = qnamelen;
566 qinf.qclass = qclass;
568 /* RD should be set only when sending the query back through the INIT
570 if(initial_state == INIT_REQUEST_STATE)
572 /* We set the CD flag so we can send this through the "head" of
573 * the resolution chain, which might have a validator. We are
574 * uninterested in validating things not on the direct resolution
581 /* attach subquery, lookup existing or make a new one */
582 fptr_ok(fptr_whitelist_modenv_attach_sub(qstate->env->attach_sub));
583 if(!(*qstate->env->attach_sub)(qstate, &qinf, qflags, prime, valrec,
589 /* initialise the new subquery */
591 subq->ext_state[id] = module_state_initial;
592 subq->minfo[id] = regional_alloc(subq->region,
593 sizeof(struct iter_qstate));
594 if(!subq->minfo[id]) {
595 log_err("init subq: out of memory");
596 fptr_ok(fptr_whitelist_modenv_kill_sub(
597 qstate->env->kill_sub));
598 (*qstate->env->kill_sub)(subq);
601 subiq = (struct iter_qstate*)subq->minfo[id];
602 memset(subiq, 0, sizeof(*subiq));
603 subiq->num_target_queries = 0;
604 target_count_create(iq);
605 subiq->target_count = iq->target_count;
607 iq->target_count[0] ++; /* extra reference */
608 subiq->num_current_queries = 0;
609 subiq->depth = iq->depth+1;
610 outbound_list_init(&subiq->outlist);
611 subiq->state = initial_state;
612 subiq->final_state = finalstate;
613 subiq->qchase = subq->qinfo;
614 subiq->chase_flags = subq->query_flags;
615 subiq->refetch_glue = 0;
616 if(qstate->env->cfg->qname_minimisation)
617 subiq->minimisation_state = INIT_MINIMISE_STATE;
619 subiq->minimisation_state = DONOT_MINIMISE_STATE;
620 memset(&subiq->qinfo_out, 0, sizeof(struct query_info));
626 * Generate and send a root priming request.
627 * @param qstate: the qtstate that triggered the need to prime.
628 * @param iq: iterator query state.
629 * @param id: module id.
630 * @param qclass: the class to prime.
631 * @return 0 on failure
634 prime_root(struct module_qstate* qstate, struct iter_qstate* iq, int id,
638 struct module_qstate* subq;
639 verbose(VERB_DETAIL, "priming . %s NS",
640 sldns_lookup_by_id(sldns_rr_classes, (int)qclass)?
641 sldns_lookup_by_id(sldns_rr_classes, (int)qclass)->name:"??");
642 dp = hints_lookup_root(qstate->env->hints, qclass);
644 verbose(VERB_ALGO, "Cannot prime due to lack of hints");
647 /* Priming requests start at the QUERYTARGETS state, skipping
648 * the normal INIT state logic (which would cause an infloop). */
649 if(!generate_sub_request((uint8_t*)"\000", 1, LDNS_RR_TYPE_NS,
650 qclass, qstate, id, iq, QUERYTARGETS_STATE, PRIME_RESP_STATE,
652 verbose(VERB_ALGO, "could not prime root");
656 struct iter_qstate* subiq =
657 (struct iter_qstate*)subq->minfo[id];
658 /* Set the initial delegation point to the hint.
659 * copy dp, it is now part of the root prime query.
660 * dp was part of in the fixed hints structure. */
661 subiq->dp = delegpt_copy(dp, subq->region);
663 log_err("out of memory priming root, copydp");
664 fptr_ok(fptr_whitelist_modenv_kill_sub(
665 qstate->env->kill_sub));
666 (*qstate->env->kill_sub)(subq);
669 /* there should not be any target queries. */
670 subiq->num_target_queries = 0;
671 subiq->dnssec_expected = iter_indicates_dnssec(
672 qstate->env, subiq->dp, NULL, subq->qinfo.qclass);
675 /* this module stops, our submodule starts, and does the query. */
676 qstate->ext_state[id] = module_wait_subquery;
681 * Generate and process a stub priming request. This method tests for the
682 * need to prime a stub zone, so it is safe to call for every request.
684 * @param qstate: the qtstate that triggered the need to prime.
685 * @param iq: iterator query state.
686 * @param id: module id.
687 * @param qname: request name.
688 * @param qclass: request class.
689 * @return true if a priming subrequest was made, false if not. The will only
690 * issue a priming request if it detects an unprimed stub.
691 * Uses value of 2 to signal during stub-prime in root-prime situation
692 * that a noprime-stub is available and resolution can continue.
695 prime_stub(struct module_qstate* qstate, struct iter_qstate* iq, int id,
696 uint8_t* qname, uint16_t qclass)
698 /* Lookup the stub hint. This will return null if the stub doesn't
699 * need to be re-primed. */
700 struct iter_hints_stub* stub;
701 struct delegpt* stub_dp;
702 struct module_qstate* subq;
705 stub = hints_lookup_stub(qstate->env->hints, qname, qclass, iq->dp);
706 /* The stub (if there is one) does not need priming. */
711 /* is it a noprime stub (always use) */
714 if(iq->dp == NULL) r = 2;
715 /* copy the dp out of the fixed hints structure, so that
716 * it can be changed when servicing this query */
717 iq->dp = delegpt_copy(stub_dp, qstate->region);
719 log_err("out of memory priming stub");
720 (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL);
721 return 1; /* return 1 to make module stop, with error */
723 log_nametypeclass(VERB_DETAIL, "use stub", stub_dp->name,
724 LDNS_RR_TYPE_NS, qclass);
728 /* Otherwise, we need to (re)prime the stub. */
729 log_nametypeclass(VERB_DETAIL, "priming stub", stub_dp->name,
730 LDNS_RR_TYPE_NS, qclass);
732 /* Stub priming events start at the QUERYTARGETS state to avoid the
733 * redundant INIT state processing. */
734 if(!generate_sub_request(stub_dp->name, stub_dp->namelen,
735 LDNS_RR_TYPE_NS, qclass, qstate, id, iq,
736 QUERYTARGETS_STATE, PRIME_RESP_STATE, &subq, 0)) {
737 verbose(VERB_ALGO, "could not prime stub");
738 (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL);
739 return 1; /* return 1 to make module stop, with error */
742 struct iter_qstate* subiq =
743 (struct iter_qstate*)subq->minfo[id];
745 /* Set the initial delegation point to the hint. */
746 /* make copy to avoid use of stub dp by different qs/threads */
747 subiq->dp = delegpt_copy(stub_dp, subq->region);
749 log_err("out of memory priming stub, copydp");
750 fptr_ok(fptr_whitelist_modenv_kill_sub(
751 qstate->env->kill_sub));
752 (*qstate->env->kill_sub)(subq);
753 (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL);
754 return 1; /* return 1 to make module stop, with error */
756 /* there should not be any target queries -- although there
757 * wouldn't be anyway, since stub hints never have
758 * missing targets. */
759 subiq->num_target_queries = 0;
760 subiq->wait_priming_stub = 1;
761 subiq->dnssec_expected = iter_indicates_dnssec(
762 qstate->env, subiq->dp, NULL, subq->qinfo.qclass);
765 /* this module stops, our submodule starts, and does the query. */
766 qstate->ext_state[id] = module_wait_subquery;
771 * Generate A and AAAA checks for glue that is in-zone for the referral
772 * we just got to obtain authoritative information on the adresses.
774 * @param qstate: the qtstate that triggered the need to prime.
775 * @param iq: iterator query state.
776 * @param id: module id.
779 generate_a_aaaa_check(struct module_qstate* qstate, struct iter_qstate* iq,
782 struct iter_env* ie = (struct iter_env*)qstate->env->modinfo[id];
783 struct module_qstate* subq;
785 struct reply_info* rep = iq->response->rep;
786 struct ub_packed_rrset_key* s;
789 if(iq->depth == ie->max_dependency_depth)
791 /* walk through additional, and check if in-zone,
792 * only relevant A, AAAA are left after scrub anyway */
793 for(i=rep->an_numrrsets+rep->ns_numrrsets; i<rep->rrset_count; i++) {
795 /* check *ALL* addresses that are transmitted in additional*/
796 /* is it an address ? */
797 if( !(ntohs(s->rk.type)==LDNS_RR_TYPE_A ||
798 ntohs(s->rk.type)==LDNS_RR_TYPE_AAAA)) {
801 /* is this query the same as the A/AAAA check for it */
802 if(qstate->qinfo.qtype == ntohs(s->rk.type) &&
803 qstate->qinfo.qclass == ntohs(s->rk.rrset_class) &&
804 query_dname_compare(qstate->qinfo.qname,
806 (qstate->query_flags&BIT_RD) &&
807 !(qstate->query_flags&BIT_CD))
810 /* generate subrequest for it */
811 log_nametypeclass(VERB_ALGO, "schedule addr fetch",
812 s->rk.dname, ntohs(s->rk.type),
813 ntohs(s->rk.rrset_class));
814 if(!generate_sub_request(s->rk.dname, s->rk.dname_len,
815 ntohs(s->rk.type), ntohs(s->rk.rrset_class),
817 INIT_REQUEST_STATE, FINISHED_STATE, &subq, 1)) {
818 verbose(VERB_ALGO, "could not generate addr check");
821 /* ignore subq - not need for more init */
826 * Generate a NS check request to obtain authoritative information
829 * @param qstate: the qtstate that triggered the need to prime.
830 * @param iq: iterator query state.
831 * @param id: module id.
834 generate_ns_check(struct module_qstate* qstate, struct iter_qstate* iq, int id)
836 struct iter_env* ie = (struct iter_env*)qstate->env->modinfo[id];
837 struct module_qstate* subq;
840 if(iq->depth == ie->max_dependency_depth)
842 /* is this query the same as the nscheck? */
843 if(qstate->qinfo.qtype == LDNS_RR_TYPE_NS &&
844 query_dname_compare(iq->dp->name, qstate->qinfo.qname)==0 &&
845 (qstate->query_flags&BIT_RD) && !(qstate->query_flags&BIT_CD)){
846 /* spawn off A, AAAA queries for in-zone glue to check */
847 generate_a_aaaa_check(qstate, iq, id);
851 log_nametypeclass(VERB_ALGO, "schedule ns fetch",
852 iq->dp->name, LDNS_RR_TYPE_NS, iq->qchase.qclass);
853 if(!generate_sub_request(iq->dp->name, iq->dp->namelen,
854 LDNS_RR_TYPE_NS, iq->qchase.qclass, qstate, id, iq,
855 INIT_REQUEST_STATE, FINISHED_STATE, &subq, 1)) {
856 verbose(VERB_ALGO, "could not generate ns check");
860 struct iter_qstate* subiq =
861 (struct iter_qstate*)subq->minfo[id];
863 /* make copy to avoid use of stub dp by different qs/threads */
864 /* refetch glue to start higher up the tree */
865 subiq->refetch_glue = 1;
866 subiq->dp = delegpt_copy(iq->dp, subq->region);
868 log_err("out of memory generating ns check, copydp");
869 fptr_ok(fptr_whitelist_modenv_kill_sub(
870 qstate->env->kill_sub));
871 (*qstate->env->kill_sub)(subq);
878 * Generate a DNSKEY prefetch query to get the DNSKEY for the DS record we
879 * just got in a referral (where we have dnssec_expected, thus have trust
880 * anchors above it). Note that right after calling this routine the
881 * iterator detached subqueries (because of following the referral), and thus
882 * the DNSKEY query becomes detached, its return stored in the cache for
883 * later lookup by the validator. This cache lookup by the validator avoids
884 * the roundtrip incurred by the DNSKEY query. The DNSKEY query is now
885 * performed at about the same time the original query is sent to the domain,
886 * thus the two answers are likely to be returned at about the same time,
887 * saving a roundtrip from the validated lookup.
889 * @param qstate: the qtstate that triggered the need to prime.
890 * @param iq: iterator query state.
891 * @param id: module id.
894 generate_dnskey_prefetch(struct module_qstate* qstate,
895 struct iter_qstate* iq, int id)
897 struct module_qstate* subq;
900 /* is this query the same as the prefetch? */
901 if(qstate->qinfo.qtype == LDNS_RR_TYPE_DNSKEY &&
902 query_dname_compare(iq->dp->name, qstate->qinfo.qname)==0 &&
903 (qstate->query_flags&BIT_RD) && !(qstate->query_flags&BIT_CD)){
907 /* if the DNSKEY is in the cache this lookup will stop quickly */
908 log_nametypeclass(VERB_ALGO, "schedule dnskey prefetch",
909 iq->dp->name, LDNS_RR_TYPE_DNSKEY, iq->qchase.qclass);
910 if(!generate_sub_request(iq->dp->name, iq->dp->namelen,
911 LDNS_RR_TYPE_DNSKEY, iq->qchase.qclass, qstate, id, iq,
912 INIT_REQUEST_STATE, FINISHED_STATE, &subq, 0)) {
913 /* we'll be slower, but it'll work */
914 verbose(VERB_ALGO, "could not generate dnskey prefetch");
918 struct iter_qstate* subiq =
919 (struct iter_qstate*)subq->minfo[id];
920 /* this qstate has the right delegation for the dnskey lookup*/
921 /* make copy to avoid use of stub dp by different qs/threads */
922 subiq->dp = delegpt_copy(iq->dp, subq->region);
923 /* if !subiq->dp, it'll start from the cache, no problem */
928 * See if the query needs forwarding.
930 * @param qstate: query state.
931 * @param iq: iterator query state.
932 * @return true if the request is forwarded, false if not.
933 * If returns true but, iq->dp is NULL then a malloc failure occurred.
936 forward_request(struct module_qstate* qstate, struct iter_qstate* iq)
939 uint8_t* delname = iq->qchase.qname;
940 size_t delnamelen = iq->qchase.qname_len;
941 if(iq->refetch_glue) {
942 delname = iq->dp->name;
943 delnamelen = iq->dp->namelen;
945 /* strip one label off of DS query to lookup higher for it */
946 if( (iq->qchase.qtype == LDNS_RR_TYPE_DS || iq->refetch_glue)
947 && !dname_is_root(iq->qchase.qname))
948 dname_remove_label(&delname, &delnamelen);
949 dp = forwards_lookup(qstate->env->fwds, delname, iq->qchase.qclass);
952 /* send recursion desired to forward addr */
953 iq->chase_flags |= BIT_RD;
954 iq->dp = delegpt_copy(dp, qstate->region);
955 /* iq->dp checked by caller */
956 verbose(VERB_ALGO, "forwarding request");
961 * Process the initial part of the request handling. This state roughly
962 * corresponds to resolver algorithms steps 1 (find answer in cache) and 2
963 * (find the best servers to ask).
965 * Note that all requests start here, and query restarts revisit this state.
967 * This state either generates: 1) a response, from cache or error, 2) a
968 * priming event, or 3) forwards the request to the next state (init2,
971 * @param qstate: query state.
972 * @param iq: iterator query state.
973 * @param ie: iterator shared global environment.
974 * @param id: module id.
975 * @return true if the event needs more request processing immediately,
979 processInitRequest(struct module_qstate* qstate, struct iter_qstate* iq,
980 struct iter_env* ie, int id)
986 log_query_info(VERB_DETAIL, "resolving", &qstate->qinfo);
989 /* We enforce a maximum number of query restarts. This is primarily a
990 * cheap way to prevent CNAME loops. */
991 if(iq->query_restart_count > MAX_RESTART_COUNT) {
992 verbose(VERB_QUERY, "request has exceeded the maximum number"
993 " of query restarts with %d", iq->query_restart_count);
994 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
997 /* We enforce a maximum recursion/dependency depth -- in general,
998 * this is unnecessary for dependency loops (although it will
999 * catch those), but it provides a sensible limit to the amount
1000 * of work required to answer a given query. */
1001 verbose(VERB_ALGO, "request has dependency depth of %d", iq->depth);
1002 if(iq->depth > ie->max_dependency_depth) {
1003 verbose(VERB_QUERY, "request has exceeded the maximum "
1004 "dependency depth with depth of %d", iq->depth);
1005 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1008 /* If the request is qclass=ANY, setup to generate each class */
1009 if(qstate->qinfo.qclass == LDNS_RR_CLASS_ANY) {
1010 iq->qchase.qclass = 0;
1011 return next_state(iq, COLLECT_CLASS_STATE);
1014 /* Resolver Algorithm Step 1 -- Look for the answer in local data. */
1016 /* This either results in a query restart (CNAME cache response), a
1017 * terminating response (ANSWER), or a cache miss (null). */
1019 if(qstate->blacklist) {
1020 /* if cache, or anything else, was blacklisted then
1021 * getting older results from cache is a bad idea, no cache */
1022 verbose(VERB_ALGO, "cache blacklisted, going to the network");
1025 msg = dns_cache_lookup(qstate->env, iq->qchase.qname,
1026 iq->qchase.qname_len, iq->qchase.qtype,
1027 iq->qchase.qclass, qstate->query_flags,
1028 qstate->region, qstate->env->scratch);
1029 if(!msg && qstate->env->neg_cache) {
1030 /* lookup in negative cache; may result in
1031 * NOERROR/NODATA or NXDOMAIN answers that need validation */
1032 msg = val_neg_getmsg(qstate->env->neg_cache, &iq->qchase,
1033 qstate->region, qstate->env->rrset_cache,
1034 qstate->env->scratch_buffer,
1035 *qstate->env->now, 1/*add SOA*/, NULL);
1037 /* item taken from cache does not match our query name, thus
1038 * security needs to be re-examined later */
1039 if(msg && query_dname_compare(qstate->qinfo.qname,
1040 iq->qchase.qname) != 0)
1041 msg->rep->security = sec_status_unchecked;
1044 /* handle positive cache response */
1045 enum response_type type = response_type_from_cache(msg,
1047 if(verbosity >= VERB_ALGO) {
1048 log_dns_msg("msg from cache lookup", &msg->qinfo,
1050 verbose(VERB_ALGO, "msg ttl is %d, prefetch ttl %d",
1052 (int)msg->rep->prefetch_ttl);
1055 if(type == RESPONSE_TYPE_CNAME) {
1058 verbose(VERB_ALGO, "returning CNAME response from "
1060 if(!handle_cname_response(qstate, iq, msg,
1062 return error_response(qstate, id,
1063 LDNS_RCODE_SERVFAIL);
1064 iq->qchase.qname = sname;
1065 iq->qchase.qname_len = slen;
1066 /* This *is* a query restart, even if it is a cheap
1069 iq->refetch_glue = 0;
1070 iq->query_restart_count++;
1072 sock_list_insert(&qstate->reply_origin, NULL, 0, qstate->region);
1073 if(qstate->env->cfg->qname_minimisation)
1074 iq->minimisation_state = INIT_MINIMISE_STATE;
1075 return next_state(iq, INIT_REQUEST_STATE);
1078 /* if from cache, NULL, else insert 'cache IP' len=0 */
1079 if(qstate->reply_origin)
1080 sock_list_insert(&qstate->reply_origin, NULL, 0, qstate->region);
1081 /* it is an answer, response, to final state */
1082 verbose(VERB_ALGO, "returning answer from cache.");
1084 return final_state(iq);
1087 /* attempt to forward the request */
1088 if(forward_request(qstate, iq))
1091 log_err("alloc failure for forward dp");
1092 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1094 iq->refetch_glue = 0;
1095 iq->minimisation_state = DONOT_MINIMISE_STATE;
1096 /* the request has been forwarded.
1097 * forwarded requests need to be immediately sent to the
1098 * next state, QUERYTARGETS. */
1099 return next_state(iq, QUERYTARGETS_STATE);
1102 /* Resolver Algorithm Step 2 -- find the "best" servers. */
1104 /* first, adjust for DS queries. To avoid the grandparent problem,
1105 * we just look for the closest set of server to the parent of qname.
1106 * When re-fetching glue we also need to ask the parent.
1108 if(iq->refetch_glue) {
1110 log_err("internal or malloc fail: no dp for refetch");
1111 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1113 delname = iq->dp->name;
1114 delnamelen = iq->dp->namelen;
1116 delname = iq->qchase.qname;
1117 delnamelen = iq->qchase.qname_len;
1119 if(iq->qchase.qtype == LDNS_RR_TYPE_DS || iq->refetch_glue ||
1120 (iq->qchase.qtype == LDNS_RR_TYPE_NS && qstate->prefetch_leeway)) {
1121 /* remove first label from delname, root goes to hints,
1122 * but only to fetch glue, not for qtype=DS. */
1123 /* also when prefetching an NS record, fetch it again from
1124 * its parent, just as if it expired, so that you do not
1125 * get stuck on an older nameserver that gives old NSrecords */
1126 if(dname_is_root(delname) && (iq->refetch_glue ||
1127 (iq->qchase.qtype == LDNS_RR_TYPE_NS &&
1128 qstate->prefetch_leeway)))
1129 delname = NULL; /* go to root priming */
1130 else dname_remove_label(&delname, &delnamelen);
1132 /* delname is the name to lookup a delegation for. If NULL rootprime */
1135 /* Lookup the delegation in the cache. If null, then the
1136 * cache needs to be primed for the qclass. */
1138 iq->dp = dns_cache_find_delegation(qstate->env, delname,
1139 delnamelen, iq->qchase.qtype, iq->qchase.qclass,
1140 qstate->region, &iq->deleg_msg,
1141 *qstate->env->now+qstate->prefetch_leeway);
1144 /* If the cache has returned nothing, then we have a
1145 * root priming situation. */
1146 if(iq->dp == NULL) {
1147 /* if there is a stub, then no root prime needed */
1148 int r = prime_stub(qstate, iq, id, delname,
1151 break; /* got noprime-stub-zone, continue */
1153 return 0; /* stub prime request made */
1154 if(forwards_lookup_root(qstate->env->fwds,
1155 iq->qchase.qclass)) {
1156 /* forward zone root, no root prime needed */
1157 /* fill in some dp - safety belt */
1158 iq->dp = hints_lookup_root(qstate->env->hints,
1161 log_err("internal error: no hints dp");
1162 return error_response(qstate, id,
1163 LDNS_RCODE_SERVFAIL);
1165 iq->dp = delegpt_copy(iq->dp, qstate->region);
1167 log_err("out of memory in safety belt");
1168 return error_response(qstate, id,
1169 LDNS_RCODE_SERVFAIL);
1171 return next_state(iq, INIT_REQUEST_2_STATE);
1173 /* Note that the result of this will set a new
1174 * DelegationPoint based on the result of priming. */
1175 if(!prime_root(qstate, iq, id, iq->qchase.qclass))
1176 return error_response(qstate, id,
1177 LDNS_RCODE_REFUSED);
1179 /* priming creates and sends a subordinate query, with
1180 * this query as the parent. So further processing for
1181 * this event will stop until reactivated by the
1182 * results of priming. */
1185 if(!iq->ratelimit_ok && qstate->prefetch_leeway)
1186 iq->ratelimit_ok = 1; /* allow prefetches, this keeps
1187 otherwise valid data in the cache */
1188 if(!iq->ratelimit_ok && infra_ratelimit_exceeded(
1189 qstate->env->infra_cache, iq->dp->name,
1190 iq->dp->namelen, *qstate->env->now)) {
1191 /* and increment the rate, so that the rate for time
1192 * now will also exceed the rate, keeping cache fresh */
1193 (void)infra_ratelimit_inc(qstate->env->infra_cache,
1194 iq->dp->name, iq->dp->namelen,
1196 /* see if we are passed through with slip factor */
1197 if(qstate->env->cfg->ratelimit_factor != 0 &&
1198 ub_random_max(qstate->env->rnd,
1199 qstate->env->cfg->ratelimit_factor) == 1) {
1200 iq->ratelimit_ok = 1;
1201 log_nametypeclass(VERB_ALGO, "ratelimit allowed through for "
1202 "delegation point", iq->dp->name,
1203 LDNS_RR_TYPE_NS, LDNS_RR_CLASS_IN);
1205 log_nametypeclass(VERB_ALGO, "ratelimit exceeded with "
1206 "delegation point", iq->dp->name,
1207 LDNS_RR_TYPE_NS, LDNS_RR_CLASS_IN);
1208 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1212 /* see if this dp not useless.
1214 * o all NS items are required glue.
1215 * or the query is for NS item that is required glue.
1216 * o no addresses are provided.
1218 * Instead, go up one level, and try to get even further
1219 * If the root was useless, use safety belt information.
1220 * Only check cache returns, because replies for servers
1221 * could be useless but lead to loops (bumping into the
1222 * same server reply) if useless-checked.
1224 if(iter_dp_is_useless(&qstate->qinfo, qstate->query_flags,
1226 if(dname_is_root(iq->dp->name)) {
1227 /* use safety belt */
1228 verbose(VERB_QUERY, "Cache has root NS but "
1229 "no addresses. Fallback to the safety belt.");
1230 iq->dp = hints_lookup_root(qstate->env->hints,
1232 /* note deleg_msg is from previous lookup,
1233 * but RD is on, so it is not used */
1235 log_err("internal error: no hints dp");
1236 return error_response(qstate, id,
1237 LDNS_RCODE_REFUSED);
1239 iq->dp = delegpt_copy(iq->dp, qstate->region);
1241 log_err("out of memory in safety belt");
1242 return error_response(qstate, id,
1243 LDNS_RCODE_SERVFAIL);
1248 "cache delegation was useless:");
1249 delegpt_log(VERB_ALGO, iq->dp);
1251 delname = iq->dp->name;
1252 delnamelen = iq->dp->namelen;
1253 dname_remove_label(&delname, &delnamelen);
1258 verbose(VERB_ALGO, "cache delegation returns delegpt");
1259 delegpt_log(VERB_ALGO, iq->dp);
1261 /* Otherwise, set the current delegation point and move on to the
1263 return next_state(iq, INIT_REQUEST_2_STATE);
1267 * Process the second part of the initial request handling. This state
1268 * basically exists so that queries that generate root priming events have
1269 * the same init processing as ones that do not. Request events that reach
1270 * this state must have a valid currentDelegationPoint set.
1272 * This part is primarly handling stub zone priming. Events that reach this
1273 * state must have a current delegation point.
1275 * @param qstate: query state.
1276 * @param iq: iterator query state.
1277 * @param id: module id.
1278 * @return true if the event needs more request processing immediately,
1282 processInitRequest2(struct module_qstate* qstate, struct iter_qstate* iq,
1287 log_query_info(VERB_QUERY, "resolving (init part 2): ",
1290 if(iq->refetch_glue) {
1292 log_err("internal or malloc fail: no dp for refetch");
1293 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1295 delname = iq->dp->name;
1296 delnamelen = iq->dp->namelen;
1298 delname = iq->qchase.qname;
1299 delnamelen = iq->qchase.qname_len;
1301 if(iq->qchase.qtype == LDNS_RR_TYPE_DS || iq->refetch_glue) {
1302 if(!dname_is_root(delname))
1303 dname_remove_label(&delname, &delnamelen);
1304 iq->refetch_glue = 0; /* if CNAME causes restart, no refetch */
1306 /* Check to see if we need to prime a stub zone. */
1307 if(prime_stub(qstate, iq, id, delname, iq->qchase.qclass)) {
1308 /* A priming sub request was made */
1312 /* most events just get forwarded to the next state. */
1313 return next_state(iq, INIT_REQUEST_3_STATE);
1317 * Process the third part of the initial request handling. This state exists
1318 * as a separate state so that queries that generate stub priming events
1319 * will get the tail end of the init process but not repeat the stub priming
1322 * @param qstate: query state.
1323 * @param iq: iterator query state.
1324 * @param id: module id.
1325 * @return true, advancing the event to the QUERYTARGETS_STATE.
1328 processInitRequest3(struct module_qstate* qstate, struct iter_qstate* iq,
1331 log_query_info(VERB_QUERY, "resolving (init part 3): ",
1333 /* if the cache reply dp equals a validation anchor or msg has DS,
1334 * then DNSSEC RRSIGs are expected in the reply */
1335 iq->dnssec_expected = iter_indicates_dnssec(qstate->env, iq->dp,
1336 iq->deleg_msg, iq->qchase.qclass);
1338 /* If the RD flag wasn't set, then we just finish with the
1339 * cached referral as the response. */
1340 if(!(qstate->query_flags & BIT_RD)) {
1341 iq->response = iq->deleg_msg;
1342 if(verbosity >= VERB_ALGO && iq->response)
1343 log_dns_msg("no RD requested, using delegation msg",
1344 &iq->response->qinfo, iq->response->rep);
1345 if(qstate->reply_origin)
1346 sock_list_insert(&qstate->reply_origin, NULL, 0, qstate->region);
1347 return final_state(iq);
1349 /* After this point, unset the RD flag -- this query is going to
1350 * be sent to an auth. server. */
1351 iq->chase_flags &= ~BIT_RD;
1353 /* if dnssec expected, fetch key for the trust-anchor or cached-DS */
1354 if(iq->dnssec_expected && qstate->env->cfg->prefetch_key &&
1355 !(qstate->query_flags&BIT_CD)) {
1356 generate_dnskey_prefetch(qstate, iq, id);
1357 fptr_ok(fptr_whitelist_modenv_detach_subs(
1358 qstate->env->detach_subs));
1359 (*qstate->env->detach_subs)(qstate);
1362 /* Jump to the next state. */
1363 return next_state(iq, QUERYTARGETS_STATE);
1367 * Given a basic query, generate a parent-side "target" query.
1368 * These are subordinate queries for missing delegation point target addresses,
1369 * for which only the parent of the delegation provides correct IP addresses.
1371 * @param qstate: query state.
1372 * @param iq: iterator query state.
1373 * @param id: module id.
1374 * @param name: target qname.
1375 * @param namelen: target qname length.
1376 * @param qtype: target qtype (either A or AAAA).
1377 * @param qclass: target qclass.
1378 * @return true on success, false on failure.
1381 generate_parentside_target_query(struct module_qstate* qstate,
1382 struct iter_qstate* iq, int id, uint8_t* name, size_t namelen,
1383 uint16_t qtype, uint16_t qclass)
1385 struct module_qstate* subq;
1386 if(!generate_sub_request(name, namelen, qtype, qclass, qstate,
1387 id, iq, INIT_REQUEST_STATE, FINISHED_STATE, &subq, 0))
1390 struct iter_qstate* subiq =
1391 (struct iter_qstate*)subq->minfo[id];
1392 /* blacklist the cache - we want to fetch parent stuff */
1393 sock_list_insert(&subq->blacklist, NULL, 0, subq->region);
1394 subiq->query_for_pside_glue = 1;
1395 if(dname_subdomain_c(name, iq->dp->name)) {
1396 subiq->dp = delegpt_copy(iq->dp, subq->region);
1397 subiq->dnssec_expected = iter_indicates_dnssec(
1398 qstate->env, subiq->dp, NULL,
1399 subq->qinfo.qclass);
1400 subiq->refetch_glue = 1;
1402 subiq->dp = dns_cache_find_delegation(qstate->env,
1403 name, namelen, qtype, qclass, subq->region,
1405 *qstate->env->now+subq->prefetch_leeway);
1406 /* if no dp, then it's from root, refetch unneeded */
1408 subiq->dnssec_expected = iter_indicates_dnssec(
1409 qstate->env, subiq->dp, NULL,
1410 subq->qinfo.qclass);
1411 subiq->refetch_glue = 1;
1415 log_nametypeclass(VERB_QUERY, "new pside target", name, qtype, qclass);
1420 * Given a basic query, generate a "target" query. These are subordinate
1421 * queries for missing delegation point target addresses.
1423 * @param qstate: query state.
1424 * @param iq: iterator query state.
1425 * @param id: module id.
1426 * @param name: target qname.
1427 * @param namelen: target qname length.
1428 * @param qtype: target qtype (either A or AAAA).
1429 * @param qclass: target qclass.
1430 * @return true on success, false on failure.
1433 generate_target_query(struct module_qstate* qstate, struct iter_qstate* iq,
1434 int id, uint8_t* name, size_t namelen, uint16_t qtype, uint16_t qclass)
1436 struct module_qstate* subq;
1437 if(!generate_sub_request(name, namelen, qtype, qclass, qstate,
1438 id, iq, INIT_REQUEST_STATE, FINISHED_STATE, &subq, 0))
1440 log_nametypeclass(VERB_QUERY, "new target", name, qtype, qclass);
1445 * Given an event at a certain state, generate zero or more target queries
1446 * for it's current delegation point.
1448 * @param qstate: query state.
1449 * @param iq: iterator query state.
1450 * @param ie: iterator shared global environment.
1451 * @param id: module id.
1452 * @param maxtargets: The maximum number of targets to query for.
1453 * if it is negative, there is no maximum number of targets.
1454 * @param num: returns the number of queries generated and processed,
1455 * which may be zero if there were no missing targets.
1456 * @return false on error.
1459 query_for_targets(struct module_qstate* qstate, struct iter_qstate* iq,
1460 struct iter_env* ie, int id, int maxtargets, int* num)
1462 int query_count = 0;
1463 struct delegpt_ns* ns;
1467 if(iq->depth == ie->max_dependency_depth)
1469 if(iq->depth > 0 && iq->target_count &&
1470 iq->target_count[1] > MAX_TARGET_COUNT) {
1471 char s[LDNS_MAX_DOMAINLEN+1];
1472 dname_str(qstate->qinfo.qname, s);
1473 verbose(VERB_QUERY, "request %s has exceeded the maximum "
1474 "number of glue fetches %d", s, iq->target_count[1]);
1478 iter_mark_cycle_targets(qstate, iq->dp);
1479 missing = (int)delegpt_count_missing_targets(iq->dp);
1480 log_assert(maxtargets != 0); /* that would not be useful */
1482 /* Generate target requests. Basically, any missing targets
1483 * are queried for here, regardless if it is necessary to do
1484 * so to continue processing. */
1485 if(maxtargets < 0 || maxtargets > missing)
1487 else toget = maxtargets;
1492 /* select 'toget' items from the total of 'missing' items */
1493 log_assert(toget <= missing);
1495 /* loop over missing targets */
1496 for(ns = iq->dp->nslist; ns; ns = ns->next) {
1500 /* randomly select this item with probability toget/missing */
1501 if(!iter_ns_probability(qstate->env->rnd, toget, missing)) {
1502 /* do not select this one, next; select toget number
1503 * of items from a list one less in size */
1508 if(ie->supports_ipv6 && !ns->got6) {
1509 /* Send the AAAA request. */
1510 if(!generate_target_query(qstate, iq, id,
1511 ns->name, ns->namelen,
1512 LDNS_RR_TYPE_AAAA, iq->qchase.qclass)) {
1515 qstate->ext_state[id] = module_wait_subquery;
1520 /* Send the A request. */
1521 if(ie->supports_ipv4 && !ns->got4) {
1522 if(!generate_target_query(qstate, iq, id,
1523 ns->name, ns->namelen,
1524 LDNS_RR_TYPE_A, iq->qchase.qclass)) {
1527 qstate->ext_state[id] = module_wait_subquery;
1533 /* mark this target as in progress. */
1542 qstate->ext_state[id] = module_wait_subquery;
1547 /** see if last resort is possible - does config allow queries to parent */
1549 can_have_last_resort(struct module_env* env, struct delegpt* dp,
1550 struct iter_qstate* iq)
1552 struct delegpt* fwddp;
1553 struct iter_hints_stub* stub;
1554 /* do not process a last resort (the parent side) if a stub
1555 * or forward is configured, because we do not want to go 'above'
1556 * the configured servers */
1557 if(!dname_is_root(dp->name) && (stub = (struct iter_hints_stub*)
1558 name_tree_find(&env->hints->tree, dp->name, dp->namelen,
1559 dp->namelabs, iq->qchase.qclass)) &&
1560 /* has_parent side is turned off for stub_first, where we
1561 * are allowed to go to the parent */
1562 stub->dp->has_parent_side_NS) {
1563 verbose(VERB_QUERY, "configured stub servers failed -- returning SERVFAIL");
1566 if((fwddp = forwards_find(env->fwds, dp->name, iq->qchase.qclass)) &&
1567 /* has_parent_side is turned off for forward_first, where
1568 * we are allowed to go to the parent */
1569 fwddp->has_parent_side_NS) {
1570 verbose(VERB_QUERY, "configured forward servers failed -- returning SERVFAIL");
1577 * Called by processQueryTargets when it would like extra targets to query
1578 * but it seems to be out of options. At last resort some less appealing
1579 * options are explored. If there are no more options, the result is SERVFAIL
1581 * @param qstate: query state.
1582 * @param iq: iterator query state.
1583 * @param ie: iterator shared global environment.
1584 * @param id: module id.
1585 * @return true if the event requires more request processing immediately,
1589 processLastResort(struct module_qstate* qstate, struct iter_qstate* iq,
1590 struct iter_env* ie, int id)
1592 struct delegpt_ns* ns;
1593 int query_count = 0;
1594 verbose(VERB_ALGO, "No more query targets, attempting last resort");
1597 if(!can_have_last_resort(qstate->env, iq->dp, iq)) {
1598 /* fail -- no more targets, no more hope of targets, no hope
1600 return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL);
1602 if(!iq->dp->has_parent_side_NS && dname_is_root(iq->dp->name)) {
1603 struct delegpt* p = hints_lookup_root(qstate->env->hints,
1606 struct delegpt_ns* ns;
1607 struct delegpt_addr* a;
1608 iq->chase_flags &= ~BIT_RD; /* go to authorities */
1609 for(ns = p->nslist; ns; ns=ns->next) {
1610 (void)delegpt_add_ns(iq->dp, qstate->region,
1611 ns->name, ns->lame);
1613 for(a = p->target_list; a; a=a->next_target) {
1614 (void)delegpt_add_addr(iq->dp, qstate->region,
1615 &a->addr, a->addrlen, a->bogus,
1619 iq->dp->has_parent_side_NS = 1;
1620 } else if(!iq->dp->has_parent_side_NS) {
1621 if(!iter_lookup_parent_NS_from_cache(qstate->env, iq->dp,
1622 qstate->region, &qstate->qinfo)
1623 || !iq->dp->has_parent_side_NS) {
1624 /* if: malloc failure in lookup go up to try */
1625 /* if: no parent NS in cache - go up one level */
1626 verbose(VERB_ALGO, "try to grab parent NS");
1627 iq->store_parent_NS = iq->dp;
1628 iq->chase_flags &= ~BIT_RD; /* go to authorities */
1629 iq->deleg_msg = NULL;
1630 iq->refetch_glue = 1;
1631 iq->query_restart_count++;
1633 if(qstate->env->cfg->qname_minimisation)
1634 iq->minimisation_state = INIT_MINIMISE_STATE;
1635 return next_state(iq, INIT_REQUEST_STATE);
1638 /* see if that makes new names available */
1639 if(!cache_fill_missing(qstate->env, iq->qchase.qclass,
1640 qstate->region, iq->dp))
1641 log_err("out of memory in cache_fill_missing");
1642 if(iq->dp->usable_list) {
1643 verbose(VERB_ALGO, "try parent-side-name, w. glue from cache");
1644 return next_state(iq, QUERYTARGETS_STATE);
1646 /* try to fill out parent glue from cache */
1647 if(iter_lookup_parent_glue_from_cache(qstate->env, iq->dp,
1648 qstate->region, &qstate->qinfo)) {
1649 /* got parent stuff from cache, see if we can continue */
1650 verbose(VERB_ALGO, "try parent-side glue from cache");
1651 return next_state(iq, QUERYTARGETS_STATE);
1653 /* query for an extra name added by the parent-NS record */
1654 if(delegpt_count_missing_targets(iq->dp) > 0) {
1656 verbose(VERB_ALGO, "try parent-side target name");
1657 if(!query_for_targets(qstate, iq, ie, id, 1, &qs)) {
1658 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1660 iq->num_target_queries += qs;
1661 target_count_increase(iq, qs);
1663 qstate->ext_state[id] = module_wait_subquery;
1664 return 0; /* and wait for them */
1667 if(iq->depth == ie->max_dependency_depth) {
1668 verbose(VERB_QUERY, "maxdepth and need more nameservers, fail");
1669 return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL);
1671 if(iq->depth > 0 && iq->target_count &&
1672 iq->target_count[1] > MAX_TARGET_COUNT) {
1673 char s[LDNS_MAX_DOMAINLEN+1];
1674 dname_str(qstate->qinfo.qname, s);
1675 verbose(VERB_QUERY, "request %s has exceeded the maximum "
1676 "number of glue fetches %d", s, iq->target_count[1]);
1677 return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL);
1679 /* mark cycle targets for parent-side lookups */
1680 iter_mark_pside_cycle_targets(qstate, iq->dp);
1681 /* see if we can issue queries to get nameserver addresses */
1682 /* this lookup is not randomized, but sequential. */
1683 for(ns = iq->dp->nslist; ns; ns = ns->next) {
1684 /* query for parent-side A and AAAA for nameservers */
1685 if(ie->supports_ipv6 && !ns->done_pside6) {
1686 /* Send the AAAA request. */
1687 if(!generate_parentside_target_query(qstate, iq, id,
1688 ns->name, ns->namelen,
1689 LDNS_RR_TYPE_AAAA, iq->qchase.qclass))
1690 return error_response(qstate, id,
1691 LDNS_RCODE_SERVFAIL);
1692 ns->done_pside6 = 1;
1695 if(ie->supports_ipv4 && !ns->done_pside4) {
1696 /* Send the A request. */
1697 if(!generate_parentside_target_query(qstate, iq, id,
1698 ns->name, ns->namelen,
1699 LDNS_RR_TYPE_A, iq->qchase.qclass))
1700 return error_response(qstate, id,
1701 LDNS_RCODE_SERVFAIL);
1702 ns->done_pside4 = 1;
1705 if(query_count != 0) { /* suspend to await results */
1706 verbose(VERB_ALGO, "try parent-side glue lookup");
1707 iq->num_target_queries += query_count;
1708 target_count_increase(iq, query_count);
1709 qstate->ext_state[id] = module_wait_subquery;
1714 /* if this was a parent-side glue query itself, then store that
1715 * failure in cache. */
1716 if(iq->query_for_pside_glue && !iq->pside_glue)
1717 iter_store_parentside_neg(qstate->env, &qstate->qinfo,
1718 iq->deleg_msg?iq->deleg_msg->rep:
1719 (iq->response?iq->response->rep:NULL));
1721 verbose(VERB_QUERY, "out of query targets -- returning SERVFAIL");
1722 /* fail -- no more targets, no more hope of targets, no hope
1724 return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL);
1728 * Try to find the NS record set that will resolve a qtype DS query. Due
1729 * to grandparent/grandchild reasons we did not get a proper lookup right
1730 * away. We need to create type NS queries until we get the right parent
1731 * for this lookup. We remove labels from the query to find the right point.
1732 * If we end up at the old dp name, then there is no solution.
1734 * @param qstate: query state.
1735 * @param iq: iterator query state.
1736 * @param id: module id.
1737 * @return true if the event requires more immediate processing, false if
1738 * not. This is generally only true when forwarding the request to
1739 * the final state (i.e., on answer).
1742 processDSNSFind(struct module_qstate* qstate, struct iter_qstate* iq, int id)
1744 struct module_qstate* subq = NULL;
1745 verbose(VERB_ALGO, "processDSNSFind");
1747 if(!iq->dsns_point) {
1749 iq->dsns_point = iq->qchase.qname;
1750 iq->dsns_point_len = iq->qchase.qname_len;
1752 /* robustcheck for internal error: we are not underneath the dp */
1753 if(!dname_subdomain_c(iq->dsns_point, iq->dp->name)) {
1754 return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL);
1757 /* go up one (more) step, until we hit the dp, if so, end */
1758 dname_remove_label(&iq->dsns_point, &iq->dsns_point_len);
1759 if(query_dname_compare(iq->dsns_point, iq->dp->name) == 0) {
1760 /* there was no inbetween nameserver, use the old delegation
1761 * point again. And this time, because dsns_point is nonNULL
1762 * we are going to accept the (bad) result */
1763 iq->state = QUERYTARGETS_STATE;
1766 iq->state = DSNS_FIND_STATE;
1768 /* spawn NS lookup (validation not needed, this is for DS lookup) */
1769 log_nametypeclass(VERB_ALGO, "fetch nameservers",
1770 iq->dsns_point, LDNS_RR_TYPE_NS, iq->qchase.qclass);
1771 if(!generate_sub_request(iq->dsns_point, iq->dsns_point_len,
1772 LDNS_RR_TYPE_NS, iq->qchase.qclass, qstate, id, iq,
1773 INIT_REQUEST_STATE, FINISHED_STATE, &subq, 0)) {
1774 return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL);
1781 * This is the request event state where the request will be sent to one of
1782 * its current query targets. This state also handles issuing target lookup
1783 * queries for missing target IP addresses. Queries typically iterate on
1784 * this state, both when they are just trying different targets for a given
1785 * delegation point, and when they change delegation points. This state
1786 * roughly corresponds to RFC 1034 algorithm steps 3 and 4.
1788 * @param qstate: query state.
1789 * @param iq: iterator query state.
1790 * @param ie: iterator shared global environment.
1791 * @param id: module id.
1792 * @return true if the event requires more request processing immediately,
1793 * false if not. This state only returns true when it is generating
1794 * a SERVFAIL response because the query has hit a dead end.
1797 processQueryTargets(struct module_qstate* qstate, struct iter_qstate* iq,
1798 struct iter_env* ie, int id)
1801 struct delegpt_addr* target;
1802 struct outbound_entry* outq;
1804 /* NOTE: a request will encounter this state for each target it
1805 * needs to send a query to. That is, at least one per referral,
1806 * more if some targets timeout or return throwaway answers. */
1808 log_query_info(VERB_QUERY, "processQueryTargets:", &qstate->qinfo);
1809 verbose(VERB_ALGO, "processQueryTargets: targetqueries %d, "
1810 "currentqueries %d sentcount %d", iq->num_target_queries,
1811 iq->num_current_queries, iq->sent_count);
1813 /* Make sure that we haven't run away */
1814 /* FIXME: is this check even necessary? */
1815 if(iq->referral_count > MAX_REFERRAL_COUNT) {
1816 verbose(VERB_QUERY, "request has exceeded the maximum "
1817 "number of referrrals with %d", iq->referral_count);
1818 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1820 if(iq->sent_count > MAX_SENT_COUNT) {
1821 verbose(VERB_QUERY, "request has exceeded the maximum "
1822 "number of sends with %d", iq->sent_count);
1823 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1826 /* Make sure we have a delegation point, otherwise priming failed
1827 * or another failure occurred */
1829 verbose(VERB_QUERY, "Failed to get a delegation, giving up");
1830 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1832 if(!ie->supports_ipv6)
1833 delegpt_no_ipv6(iq->dp);
1834 if(!ie->supports_ipv4)
1835 delegpt_no_ipv4(iq->dp);
1836 delegpt_log(VERB_ALGO, iq->dp);
1838 if(iq->num_current_queries>0) {
1839 /* already busy answering a query, this restart is because
1840 * more delegpt addrs became available, wait for existing
1842 verbose(VERB_ALGO, "woke up, but wait for outstanding query");
1843 qstate->ext_state[id] = module_wait_reply;
1848 /* < not <=, because although the array is large enough for <=, the
1849 * generated query will immediately be discarded due to depth and
1850 * that servfail is cached, which is not good as opportunism goes. */
1851 if(iq->depth < ie->max_dependency_depth
1852 && iq->sent_count < TARGET_FETCH_STOP) {
1853 tf_policy = ie->target_fetch_policy[iq->depth];
1856 /* if in 0x20 fallback get as many targets as possible */
1857 if(iq->caps_fallback) {
1859 size_t naddr, nres, navail;
1860 if(!query_for_targets(qstate, iq, ie, id, -1, &extra)) {
1861 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1863 iq->num_target_queries += extra;
1864 target_count_increase(iq, extra);
1865 if(iq->num_target_queries > 0) {
1866 /* wait to get all targets, we want to try em */
1867 verbose(VERB_ALGO, "wait for all targets for fallback");
1868 qstate->ext_state[id] = module_wait_reply;
1871 /* did we do enough fallback queries already? */
1872 delegpt_count_addr(iq->dp, &naddr, &nres, &navail);
1873 /* the current caps_server is the number of fallbacks sent.
1874 * the original query is one that matched too, so we have
1875 * caps_server+1 number of matching queries now */
1876 if(iq->caps_server+1 >= naddr*3 ||
1877 iq->caps_server*2+2 >= MAX_SENT_COUNT) {
1878 /* *2 on sentcount check because ipv6 may fail */
1879 /* we're done, process the response */
1880 verbose(VERB_ALGO, "0x20 fallback had %d responses "
1881 "match for %d wanted, done.",
1882 (int)iq->caps_server+1, (int)naddr*3);
1883 iq->response = iq->caps_response;
1884 iq->caps_fallback = 0;
1885 iter_dec_attempts(iq->dp, 3); /* space for fallback */
1886 iq->num_current_queries++; /* RespState decrements it*/
1887 iq->referral_count++; /* make sure we don't loop */
1889 iq->state = QUERY_RESP_STATE;
1892 verbose(VERB_ALGO, "0x20 fallback number %d",
1893 (int)iq->caps_server);
1895 /* if there is a policy to fetch missing targets
1896 * opportunistically, do it. we rely on the fact that once a
1897 * query (or queries) for a missing name have been issued,
1898 * they will not show up again. */
1899 } else if(tf_policy != 0) {
1901 verbose(VERB_ALGO, "attempt to get extra %d targets",
1903 (void)query_for_targets(qstate, iq, ie, id, tf_policy, &extra);
1904 /* errors ignored, these targets are not strictly necessary for
1905 * this result, we do not have to reply with SERVFAIL */
1906 iq->num_target_queries += extra;
1907 target_count_increase(iq, extra);
1910 /* Add the current set of unused targets to our queue. */
1911 delegpt_add_unused_targets(iq->dp);
1913 /* Select the next usable target, filtering out unsuitable targets. */
1914 target = iter_server_selection(ie, qstate->env, iq->dp,
1915 iq->dp->name, iq->dp->namelen, iq->qchase.qtype,
1916 &iq->dnssec_lame_query, &iq->chase_to_rd,
1917 iq->num_target_queries, qstate->blacklist);
1919 /* If no usable target was selected... */
1921 /* Here we distinguish between three states: generate a new
1922 * target query, just wait, or quit (with a SERVFAIL).
1923 * We have the following information: number of active
1924 * target queries, number of active current queries,
1925 * the presence of missing targets at this delegation
1926 * point, and the given query target policy. */
1928 /* Check for the wait condition. If this is true, then
1929 * an action must be taken. */
1930 if(iq->num_target_queries==0 && iq->num_current_queries==0) {
1931 /* If there is nothing to wait for, then we need
1932 * to distinguish between generating (a) new target
1933 * query, or failing. */
1934 if(delegpt_count_missing_targets(iq->dp) > 0) {
1936 verbose(VERB_ALGO, "querying for next "
1938 if(!query_for_targets(qstate, iq, ie, id,
1940 return error_response(qstate, id,
1941 LDNS_RCODE_SERVFAIL);
1944 delegpt_count_missing_targets(iq->dp) == 0){
1945 /* it looked like there were missing
1946 * targets, but they did not turn up.
1947 * Try the bad choices again (if any),
1948 * when we get back here missing==0,
1949 * so this is not a loop. */
1952 iq->num_target_queries += qs;
1953 target_count_increase(iq, qs);
1955 /* Since a target query might have been made, we
1956 * need to check again. */
1957 if(iq->num_target_queries == 0) {
1958 /* if in capsforid fallback, instead of last
1959 * resort, we agree with the current reply
1960 * we have (if any) (our count of addrs bad)*/
1961 if(iq->caps_fallback && iq->caps_reply) {
1962 /* we're done, process the response */
1963 verbose(VERB_ALGO, "0x20 fallback had %d responses, "
1964 "but no more servers except "
1965 "last resort, done.",
1966 (int)iq->caps_server+1);
1967 iq->response = iq->caps_response;
1968 iq->caps_fallback = 0;
1969 iter_dec_attempts(iq->dp, 3); /* space for fallback */
1970 iq->num_current_queries++; /* RespState decrements it*/
1971 iq->referral_count++; /* make sure we don't loop */
1973 iq->state = QUERY_RESP_STATE;
1976 return processLastResort(qstate, iq, ie, id);
1980 /* otherwise, we have no current targets, so submerge
1981 * until one of the target or direct queries return. */
1982 if(iq->num_target_queries>0 && iq->num_current_queries>0) {
1983 verbose(VERB_ALGO, "no current targets -- waiting "
1984 "for %d targets to resolve or %d outstanding"
1985 " queries to respond", iq->num_target_queries,
1986 iq->num_current_queries);
1987 qstate->ext_state[id] = module_wait_reply;
1988 } else if(iq->num_target_queries>0) {
1989 verbose(VERB_ALGO, "no current targets -- waiting "
1990 "for %d targets to resolve.",
1991 iq->num_target_queries);
1992 qstate->ext_state[id] = module_wait_subquery;
1994 verbose(VERB_ALGO, "no current targets -- waiting "
1995 "for %d outstanding queries to respond.",
1996 iq->num_current_queries);
1997 qstate->ext_state[id] = module_wait_reply;
2002 /* if not forwarding, check ratelimits per delegationpoint name */
2003 if(!(iq->chase_flags & BIT_RD) && !iq->ratelimit_ok) {
2004 if(!infra_ratelimit_inc(qstate->env->infra_cache, iq->dp->name,
2005 iq->dp->namelen, *qstate->env->now)) {
2006 verbose(VERB_ALGO, "query exceeded ratelimits");
2007 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
2011 if(iq->minimisation_state == INIT_MINIMISE_STATE) {
2012 /* (Re)set qinfo_out to (new) delegation point, except
2013 * when qinfo_out is already a subdomain of dp. This happens
2014 * when resolving ip6.arpa dnames. */
2015 if(!(iq->qinfo_out.qname_len
2016 && dname_subdomain_c(iq->qchase.qname,
2017 iq->qinfo_out.qname)
2018 && dname_subdomain_c(iq->qinfo_out.qname,
2020 iq->qinfo_out.qname = iq->dp->name;
2021 iq->qinfo_out.qname_len = iq->dp->namelen;
2022 iq->qinfo_out.qtype = LDNS_RR_TYPE_NS;
2023 iq->qinfo_out.qclass = iq->qchase.qclass;
2026 iq->minimisation_state = MINIMISE_STATE;
2028 if(iq->minimisation_state == MINIMISE_STATE) {
2029 int labdiff = dname_count_labels(iq->qchase.qname) -
2030 dname_count_labels(iq->qinfo_out.qname);
2032 iq->qinfo_out.qname = iq->qchase.qname;
2033 iq->qinfo_out.qname_len = iq->qchase.qname_len;
2035 /* Special treatment for ip6.arpa lookups.
2036 * Reverse IPv6 dname has 34 labels, increment the IP part
2037 * (usually first 32 labels) by 8 labels (7 more than the
2038 * default 1 label increment). */
2040 dname_subdomain_c(iq->qchase.qname, ie->ip6arpa_dname)) {
2042 /* Small chance of zone cut after first label. Stop
2049 verbose(VERB_QUERY, "removing %d labels", labdiff-1);
2050 dname_remove_labels(&iq->qinfo_out.qname,
2051 &iq->qinfo_out.qname_len,
2055 (labdiff < 2 && iq->qchase.qtype == LDNS_RR_TYPE_DS))
2056 /* Stop minimising this query, resolve "as usual" */
2057 iq->minimisation_state = DONOT_MINIMISE_STATE;
2059 struct dns_msg* msg = dns_cache_lookup(qstate->env,
2060 iq->qinfo_out.qname, iq->qinfo_out.qname_len,
2061 iq->qinfo_out.qtype, iq->qinfo_out.qclass,
2062 qstate->query_flags, qstate->region,
2063 qstate->env->scratch);
2064 if(msg && msg->rep->an_numrrsets == 0
2065 && FLAGS_GET_RCODE(msg->rep->flags) ==
2067 /* no need to send query if it is already
2068 * cached as NOERROR/NODATA */
2073 if(iq->minimisation_state == SKIP_MINIMISE_STATE)
2074 /* Do not increment qname, continue incrementing next
2076 iq->minimisation_state = MINIMISE_STATE;
2077 if(iq->minimisation_state == DONOT_MINIMISE_STATE)
2078 iq->qinfo_out = iq->qchase;
2080 /* We have a valid target. */
2081 if(verbosity >= VERB_QUERY) {
2082 log_query_info(VERB_QUERY, "sending query:", &iq->qinfo_out);
2083 log_name_addr(VERB_QUERY, "sending to target:", iq->dp->name,
2084 &target->addr, target->addrlen);
2085 verbose(VERB_ALGO, "dnssec status: %s%s",
2086 iq->dnssec_expected?"expected": "not expected",
2087 iq->dnssec_lame_query?" but lame_query anyway": "");
2089 fptr_ok(fptr_whitelist_modenv_send_query(qstate->env->send_query));
2090 outq = (*qstate->env->send_query)(
2091 iq->qinfo_out.qname, iq->qinfo_out.qname_len,
2092 iq->qinfo_out.qtype, iq->qinfo_out.qclass,
2093 iq->chase_flags | (iq->chase_to_rd?BIT_RD:0), EDNS_DO|BIT_CD,
2094 iq->dnssec_expected, iq->caps_fallback || is_caps_whitelisted(
2095 ie, iq), &target->addr, target->addrlen, iq->dp->name,
2096 iq->dp->namelen, qstate);
2098 log_addr(VERB_DETAIL, "error sending query to auth server",
2099 &target->addr, target->addrlen);
2100 if(!(iq->chase_flags & BIT_RD) && !iq->ratelimit_ok)
2101 infra_ratelimit_dec(qstate->env->infra_cache, iq->dp->name,
2102 iq->dp->namelen, *qstate->env->now);
2103 return next_state(iq, QUERYTARGETS_STATE);
2105 outbound_list_insert(&iq->outlist, outq);
2106 iq->num_current_queries++;
2108 qstate->ext_state[id] = module_wait_reply;
2113 /** find NS rrset in given list */
2114 static struct ub_packed_rrset_key*
2115 find_NS(struct reply_info* rep, size_t from, size_t to)
2118 for(i=from; i<to; i++) {
2119 if(ntohs(rep->rrsets[i]->rk.type) == LDNS_RR_TYPE_NS)
2120 return rep->rrsets[i];
2127 * Process the query response. All queries end up at this state first. This
2128 * process generally consists of analyzing the response and routing the
2129 * event to the next state (either bouncing it back to a request state, or
2130 * terminating the processing for this event).
2132 * @param qstate: query state.
2133 * @param iq: iterator query state.
2134 * @param id: module id.
2135 * @return true if the event requires more immediate processing, false if
2136 * not. This is generally only true when forwarding the request to
2137 * the final state (i.e., on answer).
2140 processQueryResponse(struct module_qstate* qstate, struct iter_qstate* iq,
2144 enum response_type type;
2145 iq->num_current_queries--;
2146 if(iq->response == NULL) {
2147 /* Don't increment qname when QNAME minimisation is enabled */
2148 if (qstate->env->cfg->qname_minimisation)
2149 iq->minimisation_state = SKIP_MINIMISE_STATE;
2150 iq->chase_to_rd = 0;
2151 iq->dnssec_lame_query = 0;
2152 verbose(VERB_ALGO, "query response was timeout");
2153 return next_state(iq, QUERYTARGETS_STATE);
2155 type = response_type_from_server(
2156 (int)((iq->chase_flags&BIT_RD) || iq->chase_to_rd),
2157 iq->response, &iq->qchase, iq->dp);
2158 iq->chase_to_rd = 0;
2159 if(type == RESPONSE_TYPE_REFERRAL && (iq->chase_flags&BIT_RD)) {
2160 /* When forwarding (RD bit is set), we handle referrals
2161 * differently. No queries should be sent elsewhere */
2162 type = RESPONSE_TYPE_ANSWER;
2164 if(iq->dnssec_expected && !iq->dnssec_lame_query &&
2165 !(iq->chase_flags&BIT_RD)
2166 && type != RESPONSE_TYPE_LAME
2167 && type != RESPONSE_TYPE_REC_LAME
2168 && type != RESPONSE_TYPE_THROWAWAY
2169 && type != RESPONSE_TYPE_UNTYPED) {
2170 /* a possible answer, see if it is missing DNSSEC */
2171 /* but not when forwarding, so we dont mark fwder lame */
2172 if(!iter_msg_has_dnssec(iq->response)) {
2173 /* Mark this address as dnsseclame in this dp,
2174 * because that will make serverselection disprefer
2175 * it, but also, once it is the only final option,
2176 * use dnssec-lame-bypass if it needs to query there.*/
2178 struct delegpt_addr* a = delegpt_find_addr(
2179 iq->dp, &qstate->reply->addr,
2180 qstate->reply->addrlen);
2181 if(a) a->dnsseclame = 1;
2183 /* test the answer is from the zone we expected,
2184 * otherwise, (due to parent,child on same server), we
2185 * might mark the server,zone lame inappropriately */
2186 if(!iter_msg_from_zone(iq->response, iq->dp, type,
2188 qstate->reply = NULL;
2189 type = RESPONSE_TYPE_LAME;
2192 } else iq->dnssec_lame_query = 0;
2193 /* see if referral brings us close to the target */
2194 if(type == RESPONSE_TYPE_REFERRAL) {
2195 struct ub_packed_rrset_key* ns = find_NS(
2196 iq->response->rep, iq->response->rep->an_numrrsets,
2197 iq->response->rep->an_numrrsets
2198 + iq->response->rep->ns_numrrsets);
2199 if(!ns) ns = find_NS(iq->response->rep, 0,
2200 iq->response->rep->an_numrrsets);
2201 if(!ns || !dname_strict_subdomain_c(ns->rk.dname, iq->dp->name)
2202 || !dname_subdomain_c(iq->qchase.qname, ns->rk.dname)){
2203 verbose(VERB_ALGO, "bad referral, throwaway");
2204 type = RESPONSE_TYPE_THROWAWAY;
2206 iter_scrub_ds(iq->response, ns, iq->dp->name);
2207 } else iter_scrub_ds(iq->response, NULL, NULL);
2209 /* handle each of the type cases */
2210 if(type == RESPONSE_TYPE_ANSWER) {
2211 /* ANSWER type responses terminate the query algorithm,
2212 * so they sent on their */
2213 if(verbosity >= VERB_DETAIL) {
2214 verbose(VERB_DETAIL, "query response was %s",
2215 FLAGS_GET_RCODE(iq->response->rep->flags)
2216 ==LDNS_RCODE_NXDOMAIN?"NXDOMAIN ANSWER":
2217 (iq->response->rep->an_numrrsets?"ANSWER":
2220 /* if qtype is DS, check we have the right level of answer,
2221 * like grandchild answer but we need the middle, reject it */
2222 if(iq->qchase.qtype == LDNS_RR_TYPE_DS && !iq->dsns_point
2223 && !(iq->chase_flags&BIT_RD)
2224 && iter_ds_toolow(iq->response, iq->dp)
2225 && iter_dp_cangodown(&iq->qchase, iq->dp)) {
2226 /* close down outstanding requests to be discarded */
2227 outbound_list_clear(&iq->outlist);
2228 iq->num_current_queries = 0;
2229 fptr_ok(fptr_whitelist_modenv_detach_subs(
2230 qstate->env->detach_subs));
2231 (*qstate->env->detach_subs)(qstate);
2232 iq->num_target_queries = 0;
2233 return processDSNSFind(qstate, iq, id);
2235 iter_dns_store(qstate->env, &iq->response->qinfo,
2236 iq->response->rep, 0, qstate->prefetch_leeway,
2237 iq->dp&&iq->dp->has_parent_side_NS,
2238 qstate->region, qstate->query_flags);
2239 /* close down outstanding requests to be discarded */
2240 outbound_list_clear(&iq->outlist);
2241 iq->num_current_queries = 0;
2242 fptr_ok(fptr_whitelist_modenv_detach_subs(
2243 qstate->env->detach_subs));
2244 (*qstate->env->detach_subs)(qstate);
2245 iq->num_target_queries = 0;
2247 sock_list_insert(&qstate->reply_origin,
2248 &qstate->reply->addr, qstate->reply->addrlen,
2250 if(iq->minimisation_state != DONOT_MINIMISE_STATE) {
2251 /* Best effort qname-minimisation.
2252 * Stop minimising and send full query when RCODE
2254 if(FLAGS_GET_RCODE(iq->response->rep->flags) !=
2256 iq->minimisation_state = DONOT_MINIMISE_STATE;
2257 return next_state(iq, QUERYTARGETS_STATE);
2259 return final_state(iq);
2260 } else if(type == RESPONSE_TYPE_REFERRAL) {
2261 /* REFERRAL type responses get a reset of the
2262 * delegation point, and back to the QUERYTARGETS_STATE. */
2263 verbose(VERB_DETAIL, "query response was REFERRAL");
2265 if(!(iq->chase_flags & BIT_RD) && !iq->ratelimit_ok) {
2266 /* we have a referral, no ratelimit, we can send
2267 * our queries to the given name */
2268 infra_ratelimit_dec(qstate->env->infra_cache,
2269 iq->dp->name, iq->dp->namelen,
2273 /* if hardened, only store referral if we asked for it */
2274 if(!qstate->env->cfg->harden_referral_path ||
2275 ( qstate->qinfo.qtype == LDNS_RR_TYPE_NS
2276 && (qstate->query_flags&BIT_RD)
2277 && !(qstate->query_flags&BIT_CD)
2278 /* we know that all other NS rrsets are scrubbed
2279 * away, thus on referral only one is left.
2280 * see if that equals the query name... */
2281 && ( /* auth section, but sometimes in answer section*/
2282 reply_find_rrset_section_ns(iq->response->rep,
2283 iq->qchase.qname, iq->qchase.qname_len,
2284 LDNS_RR_TYPE_NS, iq->qchase.qclass)
2285 || reply_find_rrset_section_an(iq->response->rep,
2286 iq->qchase.qname, iq->qchase.qname_len,
2287 LDNS_RR_TYPE_NS, iq->qchase.qclass)
2290 /* Store the referral under the current query */
2291 /* no prefetch-leeway, since its not the answer */
2292 iter_dns_store(qstate->env, &iq->response->qinfo,
2293 iq->response->rep, 1, 0, 0, NULL, 0);
2294 if(iq->store_parent_NS)
2295 iter_store_parentside_NS(qstate->env,
2297 if(qstate->env->neg_cache)
2298 val_neg_addreferral(qstate->env->neg_cache,
2299 iq->response->rep, iq->dp->name);
2301 /* store parent-side-in-zone-glue, if directly queried for */
2302 if(iq->query_for_pside_glue && !iq->pside_glue) {
2303 iq->pside_glue = reply_find_rrset(iq->response->rep,
2304 iq->qchase.qname, iq->qchase.qname_len,
2305 iq->qchase.qtype, iq->qchase.qclass);
2306 if(iq->pside_glue) {
2307 log_rrset_key(VERB_ALGO, "found parent-side "
2308 "glue", iq->pside_glue);
2309 iter_store_parentside_rrset(qstate->env,
2314 /* Reset the event state, setting the current delegation
2315 * point to the referral. */
2316 iq->deleg_msg = iq->response;
2317 iq->dp = delegpt_from_message(iq->response, qstate->region);
2318 if (qstate->env->cfg->qname_minimisation)
2319 iq->minimisation_state = INIT_MINIMISE_STATE;
2321 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
2322 if(!cache_fill_missing(qstate->env, iq->qchase.qclass,
2323 qstate->region, iq->dp))
2324 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
2325 if(iq->store_parent_NS && query_dname_compare(iq->dp->name,
2326 iq->store_parent_NS->name) == 0)
2327 iter_merge_retry_counts(iq->dp, iq->store_parent_NS);
2328 delegpt_log(VERB_ALGO, iq->dp);
2329 /* Count this as a referral. */
2330 iq->referral_count++;
2332 /* see if the next dp is a trust anchor, or a DS was sent
2333 * along, indicating dnssec is expected for next zone */
2334 iq->dnssec_expected = iter_indicates_dnssec(qstate->env,
2335 iq->dp, iq->response, iq->qchase.qclass);
2336 /* if dnssec, validating then also fetch the key for the DS */
2337 if(iq->dnssec_expected && qstate->env->cfg->prefetch_key &&
2338 !(qstate->query_flags&BIT_CD))
2339 generate_dnskey_prefetch(qstate, iq, id);
2341 /* spawn off NS and addr to auth servers for the NS we just
2342 * got in the referral. This gets authoritative answer
2343 * (answer section trust level) rrset.
2344 * right after, we detach the subs, answer goes to cache. */
2345 if(qstate->env->cfg->harden_referral_path)
2346 generate_ns_check(qstate, iq, id);
2348 /* stop current outstanding queries.
2349 * FIXME: should the outstanding queries be waited for and
2350 * handled? Say by a subquery that inherits the outbound_entry.
2352 outbound_list_clear(&iq->outlist);
2353 iq->num_current_queries = 0;
2354 fptr_ok(fptr_whitelist_modenv_detach_subs(
2355 qstate->env->detach_subs));
2356 (*qstate->env->detach_subs)(qstate);
2357 iq->num_target_queries = 0;
2358 verbose(VERB_ALGO, "cleared outbound list for next round");
2359 return next_state(iq, QUERYTARGETS_STATE);
2360 } else if(type == RESPONSE_TYPE_CNAME) {
2361 uint8_t* sname = NULL;
2362 size_t snamelen = 0;
2363 /* CNAME type responses get a query restart (i.e., get a
2364 * reset of the query state and go back to INIT_REQUEST_STATE).
2366 verbose(VERB_DETAIL, "query response was CNAME");
2367 if(verbosity >= VERB_ALGO)
2368 log_dns_msg("cname msg", &iq->response->qinfo,
2370 /* if qtype is DS, check we have the right level of answer,
2371 * like grandchild answer but we need the middle, reject it */
2372 if(iq->qchase.qtype == LDNS_RR_TYPE_DS && !iq->dsns_point
2373 && !(iq->chase_flags&BIT_RD)
2374 && iter_ds_toolow(iq->response, iq->dp)
2375 && iter_dp_cangodown(&iq->qchase, iq->dp)) {
2376 outbound_list_clear(&iq->outlist);
2377 iq->num_current_queries = 0;
2378 fptr_ok(fptr_whitelist_modenv_detach_subs(
2379 qstate->env->detach_subs));
2380 (*qstate->env->detach_subs)(qstate);
2381 iq->num_target_queries = 0;
2382 return processDSNSFind(qstate, iq, id);
2384 /* Process the CNAME response. */
2385 if(!handle_cname_response(qstate, iq, iq->response,
2387 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
2388 /* cache the CNAME response under the current query */
2389 /* NOTE : set referral=1, so that rrsets get stored but not
2390 * the partial query answer (CNAME only). */
2391 /* prefetchleeway applied because this updates answer parts */
2392 iter_dns_store(qstate->env, &iq->response->qinfo,
2393 iq->response->rep, 1, qstate->prefetch_leeway,
2394 iq->dp&&iq->dp->has_parent_side_NS, NULL,
2395 qstate->query_flags);
2396 /* set the current request's qname to the new value. */
2397 iq->qchase.qname = sname;
2398 iq->qchase.qname_len = snamelen;
2399 if (qstate->env->cfg->qname_minimisation)
2400 iq->minimisation_state = INIT_MINIMISE_STATE;
2401 /* Clear the query state, since this is a query restart. */
2402 iq->deleg_msg = NULL;
2404 iq->dsns_point = NULL;
2405 /* Note the query restart. */
2406 iq->query_restart_count++;
2409 /* stop current outstanding queries.
2410 * FIXME: should the outstanding queries be waited for and
2411 * handled? Say by a subquery that inherits the outbound_entry.
2413 outbound_list_clear(&iq->outlist);
2414 iq->num_current_queries = 0;
2415 fptr_ok(fptr_whitelist_modenv_detach_subs(
2416 qstate->env->detach_subs));
2417 (*qstate->env->detach_subs)(qstate);
2418 iq->num_target_queries = 0;
2420 sock_list_insert(&qstate->reply_origin,
2421 &qstate->reply->addr, qstate->reply->addrlen,
2423 verbose(VERB_ALGO, "cleared outbound list for query restart");
2424 /* go to INIT_REQUEST_STATE for new qname. */
2425 return next_state(iq, INIT_REQUEST_STATE);
2426 } else if(type == RESPONSE_TYPE_LAME) {
2427 /* Cache the LAMEness. */
2428 verbose(VERB_DETAIL, "query response was %sLAME",
2429 dnsseclame?"DNSSEC ":"");
2430 if(!dname_subdomain_c(iq->qchase.qname, iq->dp->name)) {
2431 log_err("mark lame: mismatch in qname and dpname");
2432 /* throwaway this reply below */
2433 } else if(qstate->reply) {
2434 /* need addr for lameness cache, but we may have
2435 * gotten this from cache, so test to be sure */
2436 if(!infra_set_lame(qstate->env->infra_cache,
2437 &qstate->reply->addr, qstate->reply->addrlen,
2438 iq->dp->name, iq->dp->namelen,
2439 *qstate->env->now, dnsseclame, 0,
2441 log_err("mark host lame: out of memory");
2443 } else if(type == RESPONSE_TYPE_REC_LAME) {
2444 /* Cache the LAMEness. */
2445 verbose(VERB_DETAIL, "query response REC_LAME: "
2446 "recursive but not authoritative server");
2447 if(!dname_subdomain_c(iq->qchase.qname, iq->dp->name)) {
2448 log_err("mark rec_lame: mismatch in qname and dpname");
2449 /* throwaway this reply below */
2450 } else if(qstate->reply) {
2451 /* need addr for lameness cache, but we may have
2452 * gotten this from cache, so test to be sure */
2453 verbose(VERB_DETAIL, "mark as REC_LAME");
2454 if(!infra_set_lame(qstate->env->infra_cache,
2455 &qstate->reply->addr, qstate->reply->addrlen,
2456 iq->dp->name, iq->dp->namelen,
2457 *qstate->env->now, 0, 1, iq->qchase.qtype))
2458 log_err("mark host lame: out of memory");
2460 } else if(type == RESPONSE_TYPE_THROWAWAY) {
2461 /* LAME and THROWAWAY responses are handled the same way.
2462 * In this case, the event is just sent directly back to
2463 * the QUERYTARGETS_STATE without resetting anything,
2464 * because, clearly, the next target must be tried. */
2465 verbose(VERB_DETAIL, "query response was THROWAWAY");
2467 log_warn("A query response came back with an unknown type: %d",
2471 /* LAME, THROWAWAY and "unknown" all end up here.
2472 * Recycle to the QUERYTARGETS state to hopefully try a
2473 * different target. */
2474 if (qstate->env->cfg->qname_minimisation)
2475 iq->minimisation_state = DONOT_MINIMISE_STATE;
2476 return next_state(iq, QUERYTARGETS_STATE);
2480 * Return priming query results to interested super querystates.
2482 * Sets the delegation point and delegation message (not nonRD queries).
2483 * This is a callback from walk_supers.
2485 * @param qstate: priming query state that finished.
2486 * @param id: module id.
2487 * @param forq: the qstate for which priming has been done.
2490 prime_supers(struct module_qstate* qstate, int id, struct module_qstate* forq)
2492 struct iter_qstate* foriq = (struct iter_qstate*)forq->minfo[id];
2493 struct delegpt* dp = NULL;
2495 log_assert(qstate->is_priming || foriq->wait_priming_stub);
2496 log_assert(qstate->return_rcode == LDNS_RCODE_NOERROR);
2497 /* Convert our response to a delegation point */
2498 dp = delegpt_from_message(qstate->return_msg, forq->region);
2500 /* if there is no convertable delegation point, then
2501 * the ANSWER type was (presumably) a negative answer. */
2502 verbose(VERB_ALGO, "prime response was not a positive "
2505 foriq->state = QUERYTARGETS_STATE;
2509 log_query_info(VERB_DETAIL, "priming successful for", &qstate->qinfo);
2510 delegpt_log(VERB_ALGO, dp);
2512 foriq->deleg_msg = dns_copy_msg(qstate->return_msg, forq->region);
2513 if(!foriq->deleg_msg) {
2514 log_err("copy prime response: out of memory");
2516 foriq->state = QUERYTARGETS_STATE;
2520 /* root priming responses go to init stage 2, priming stub
2521 * responses to to stage 3. */
2522 if(foriq->wait_priming_stub) {
2523 foriq->state = INIT_REQUEST_3_STATE;
2524 foriq->wait_priming_stub = 0;
2525 } else foriq->state = INIT_REQUEST_2_STATE;
2526 /* because we are finished, the parent will be reactivated */
2530 * This handles the response to a priming query. This is used to handle both
2531 * root and stub priming responses. This is basically the equivalent of the
2532 * QUERY_RESP_STATE, but will not handle CNAME responses and will treat
2533 * REFERRALs as ANSWERS. It will also update and reactivate the originating
2536 * @param qstate: query state.
2537 * @param id: module id.
2538 * @return true if the event needs more immediate processing, false if not.
2539 * This state always returns false.
2542 processPrimeResponse(struct module_qstate* qstate, int id)
2544 struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id];
2545 enum response_type type;
2546 iq->response->rep->flags &= ~(BIT_RD|BIT_RA); /* ignore rec-lame */
2547 type = response_type_from_server(
2548 (int)((iq->chase_flags&BIT_RD) || iq->chase_to_rd),
2549 iq->response, &iq->qchase, iq->dp);
2550 if(type == RESPONSE_TYPE_ANSWER) {
2551 qstate->return_rcode = LDNS_RCODE_NOERROR;
2552 qstate->return_msg = iq->response;
2554 qstate->return_rcode = LDNS_RCODE_SERVFAIL;
2555 qstate->return_msg = NULL;
2558 /* validate the root or stub after priming (if enabled).
2559 * This is the same query as the prime query, but with validation.
2560 * Now that we are primed, the additional queries that validation
2561 * may need can be resolved, such as DLV. */
2562 if(qstate->env->cfg->harden_referral_path) {
2563 struct module_qstate* subq = NULL;
2564 log_nametypeclass(VERB_ALGO, "schedule prime validation",
2565 qstate->qinfo.qname, qstate->qinfo.qtype,
2566 qstate->qinfo.qclass);
2567 if(!generate_sub_request(qstate->qinfo.qname,
2568 qstate->qinfo.qname_len, qstate->qinfo.qtype,
2569 qstate->qinfo.qclass, qstate, id, iq,
2570 INIT_REQUEST_STATE, FINISHED_STATE, &subq, 1)) {
2571 verbose(VERB_ALGO, "could not generate prime check");
2573 generate_a_aaaa_check(qstate, iq, id);
2576 /* This event is finished. */
2577 qstate->ext_state[id] = module_finished;
2582 * Do final processing on responses to target queries. Events reach this
2583 * state after the iterative resolution algorithm terminates. This state is
2584 * responsible for reactiving the original event, and housekeeping related
2585 * to received target responses (caching, updating the current delegation
2587 * Callback from walk_supers for every super state that is interested in
2588 * the results from this query.
2590 * @param qstate: query state.
2591 * @param id: module id.
2592 * @param forq: super query state.
2595 processTargetResponse(struct module_qstate* qstate, int id,
2596 struct module_qstate* forq)
2598 struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id];
2599 struct iter_qstate* foriq = (struct iter_qstate*)forq->minfo[id];
2600 struct ub_packed_rrset_key* rrset;
2601 struct delegpt_ns* dpns;
2602 log_assert(qstate->return_rcode == LDNS_RCODE_NOERROR);
2604 foriq->state = QUERYTARGETS_STATE;
2605 log_query_info(VERB_ALGO, "processTargetResponse", &qstate->qinfo);
2606 log_query_info(VERB_ALGO, "processTargetResponse super", &forq->qinfo);
2608 /* check to see if parent event is still interested (in orig name). */
2610 verbose(VERB_ALGO, "subq: parent not interested, was reset");
2611 return; /* not interested anymore */
2613 dpns = delegpt_find_ns(foriq->dp, qstate->qinfo.qname,
2614 qstate->qinfo.qname_len);
2616 /* If not interested, just stop processing this event */
2617 verbose(VERB_ALGO, "subq: parent not interested anymore");
2618 /* could be because parent was jostled out of the cache,
2619 and a new identical query arrived, that does not want it*/
2623 /* Tell the originating event that this target query has finished
2624 * (regardless if it succeeded or not). */
2625 foriq->num_target_queries--;
2627 /* if iq->query_for_pside_glue then add the pside_glue (marked lame) */
2628 if(iq->pside_glue) {
2629 /* if the pside_glue is NULL, then it could not be found,
2630 * the done_pside is already set when created and a cache
2631 * entry created in processFinished so nothing to do here */
2632 log_rrset_key(VERB_ALGO, "add parentside glue to dp",
2634 if(!delegpt_add_rrset(foriq->dp, forq->region,
2636 log_err("out of memory adding pside glue");
2639 /* This response is relevant to the current query, so we
2640 * add (attempt to add, anyway) this target(s) and reactivate
2641 * the original event.
2642 * NOTE: we could only look for the AnswerRRset if the
2643 * response type was ANSWER. */
2644 rrset = reply_find_answer_rrset(&iq->qchase, qstate->return_msg->rep);
2646 /* if CNAMEs have been followed - add new NS to delegpt. */
2647 /* BTW. RFC 1918 says NS should not have got CNAMEs. Robust. */
2648 if(!delegpt_find_ns(foriq->dp, rrset->rk.dname,
2649 rrset->rk.dname_len)) {
2650 /* if dpns->lame then set newcname ns lame too */
2651 if(!delegpt_add_ns(foriq->dp, forq->region,
2652 rrset->rk.dname, dpns->lame))
2653 log_err("out of memory adding cnamed-ns");
2655 /* if dpns->lame then set the address(es) lame too */
2656 if(!delegpt_add_rrset(foriq->dp, forq->region, rrset,
2658 log_err("out of memory adding targets");
2659 verbose(VERB_ALGO, "added target response");
2660 delegpt_log(VERB_ALGO, foriq->dp);
2662 verbose(VERB_ALGO, "iterator TargetResponse failed");
2663 dpns->resolved = 1; /* fail the target */
2668 * Process response for DS NS Find queries, that attempt to find the delegation
2669 * point where we ask the DS query from.
2671 * @param qstate: query state.
2672 * @param id: module id.
2673 * @param forq: super query state.
2676 processDSNSResponse(struct module_qstate* qstate, int id,
2677 struct module_qstate* forq)
2679 struct iter_qstate* foriq = (struct iter_qstate*)forq->minfo[id];
2681 /* if the finished (iq->response) query has no NS set: continue
2682 * up to look for the right dp; nothing to change, do DPNSstate */
2683 if(qstate->return_rcode != LDNS_RCODE_NOERROR)
2684 return; /* seek further */
2685 /* find the NS RRset (without allowing CNAMEs) */
2686 if(!reply_find_rrset(qstate->return_msg->rep, qstate->qinfo.qname,
2687 qstate->qinfo.qname_len, LDNS_RR_TYPE_NS,
2688 qstate->qinfo.qclass)){
2689 return; /* seek further */
2692 /* else, store as DP and continue at querytargets */
2693 foriq->state = QUERYTARGETS_STATE;
2694 foriq->dp = delegpt_from_message(qstate->return_msg, forq->region);
2696 log_err("out of memory in dsns dp alloc");
2697 return; /* dp==NULL in QUERYTARGETS makes SERVFAIL */
2699 /* success, go query the querytargets in the new dp (and go down) */
2703 * Process response for qclass=ANY queries for a particular class.
2704 * Append to result or error-exit.
2706 * @param qstate: query state.
2707 * @param id: module id.
2708 * @param forq: super query state.
2711 processClassResponse(struct module_qstate* qstate, int id,
2712 struct module_qstate* forq)
2714 struct iter_qstate* foriq = (struct iter_qstate*)forq->minfo[id];
2715 struct dns_msg* from = qstate->return_msg;
2716 log_query_info(VERB_ALGO, "processClassResponse", &qstate->qinfo);
2717 log_query_info(VERB_ALGO, "processClassResponse super", &forq->qinfo);
2718 if(qstate->return_rcode != LDNS_RCODE_NOERROR) {
2719 /* cause servfail for qclass ANY query */
2720 foriq->response = NULL;
2721 foriq->state = FINISHED_STATE;
2725 if(!foriq->response) {
2726 /* allocate the response: copy RCODE, sec_state */
2727 foriq->response = dns_copy_msg(from, forq->region);
2728 if(!foriq->response) {
2729 log_err("malloc failed for qclass ANY response");
2730 foriq->state = FINISHED_STATE;
2733 foriq->response->qinfo.qclass = forq->qinfo.qclass;
2734 /* qclass ANY does not receive the AA flag on replies */
2735 foriq->response->rep->authoritative = 0;
2737 struct dns_msg* to = foriq->response;
2738 /* add _from_ this response _to_ existing collection */
2739 /* if there are records, copy RCODE */
2740 /* lower sec_state if this message is lower */
2741 if(from->rep->rrset_count != 0) {
2742 size_t n = from->rep->rrset_count+to->rep->rrset_count;
2743 struct ub_packed_rrset_key** dest, **d;
2744 /* copy appropriate rcode */
2745 to->rep->flags = from->rep->flags;
2747 if(from->rep->rrset_count > RR_COUNT_MAX ||
2748 to->rep->rrset_count > RR_COUNT_MAX) {
2749 log_err("malloc failed (too many rrsets) in collect ANY");
2750 foriq->state = FINISHED_STATE;
2751 return; /* integer overflow protection */
2753 dest = regional_alloc(forq->region, sizeof(dest[0])*n);
2755 log_err("malloc failed in collect ANY");
2756 foriq->state = FINISHED_STATE;
2761 memcpy(dest, to->rep->rrsets, to->rep->an_numrrsets
2763 dest += to->rep->an_numrrsets;
2764 memcpy(dest, from->rep->rrsets, from->rep->an_numrrsets
2766 dest += from->rep->an_numrrsets;
2768 memcpy(dest, to->rep->rrsets+to->rep->an_numrrsets,
2769 to->rep->ns_numrrsets * sizeof(dest[0]));
2770 dest += to->rep->ns_numrrsets;
2771 memcpy(dest, from->rep->rrsets+from->rep->an_numrrsets,
2772 from->rep->ns_numrrsets * sizeof(dest[0]));
2773 dest += from->rep->ns_numrrsets;
2775 memcpy(dest, to->rep->rrsets+to->rep->an_numrrsets+
2776 to->rep->ns_numrrsets,
2777 to->rep->ar_numrrsets * sizeof(dest[0]));
2778 dest += to->rep->ar_numrrsets;
2779 memcpy(dest, from->rep->rrsets+from->rep->an_numrrsets+
2780 from->rep->ns_numrrsets,
2781 from->rep->ar_numrrsets * sizeof(dest[0]));
2783 to->rep->rrsets = d;
2784 to->rep->an_numrrsets += from->rep->an_numrrsets;
2785 to->rep->ns_numrrsets += from->rep->ns_numrrsets;
2786 to->rep->ar_numrrsets += from->rep->ar_numrrsets;
2787 to->rep->rrset_count = n;
2789 if(from->rep->security < to->rep->security) /* lowest sec */
2790 to->rep->security = from->rep->security;
2791 if(from->rep->qdcount != 0) /* insert qd if appropriate */
2792 to->rep->qdcount = from->rep->qdcount;
2793 if(from->rep->ttl < to->rep->ttl) /* use smallest TTL */
2794 to->rep->ttl = from->rep->ttl;
2795 if(from->rep->prefetch_ttl < to->rep->prefetch_ttl)
2796 to->rep->prefetch_ttl = from->rep->prefetch_ttl;
2799 foriq->num_current_queries --;
2800 if(foriq->num_current_queries == 0)
2801 foriq->state = FINISHED_STATE;
2805 * Collect class ANY responses and make them into one response. This
2806 * state is started and it creates queries for all classes (that have
2807 * root hints). The answers are then collected.
2809 * @param qstate: query state.
2810 * @param id: module id.
2811 * @return true if the event needs more immediate processing, false if not.
2814 processCollectClass(struct module_qstate* qstate, int id)
2816 struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id];
2817 struct module_qstate* subq;
2818 /* If qchase.qclass == 0 then send out queries for all classes.
2819 * Otherwise, do nothing (wait for all answers to arrive and the
2820 * processClassResponse to put them together, and that moves us
2821 * towards the Finished state when done. */
2822 if(iq->qchase.qclass == 0) {
2824 iq->qchase.qclass = LDNS_RR_CLASS_ANY;
2825 while(iter_get_next_root(qstate->env->hints,
2826 qstate->env->fwds, &c)) {
2827 /* generate query for this class */
2828 log_nametypeclass(VERB_ALGO, "spawn collect query",
2829 qstate->qinfo.qname, qstate->qinfo.qtype, c);
2830 if(!generate_sub_request(qstate->qinfo.qname,
2831 qstate->qinfo.qname_len, qstate->qinfo.qtype,
2832 c, qstate, id, iq, INIT_REQUEST_STATE,
2833 FINISHED_STATE, &subq,
2834 (int)!(qstate->query_flags&BIT_CD))) {
2835 return error_response(qstate, id,
2836 LDNS_RCODE_SERVFAIL);
2838 /* ignore subq, no special init required */
2839 iq->num_current_queries ++;
2844 /* if no roots are configured at all, return */
2845 if(iq->num_current_queries == 0) {
2846 verbose(VERB_ALGO, "No root hints or fwds, giving up "
2848 return error_response(qstate, id, LDNS_RCODE_REFUSED);
2850 /* return false, wait for queries to return */
2852 /* if woke up here because of an answer, wait for more answers */
2857 * This handles the final state for first-tier responses (i.e., responses to
2858 * externally generated queries).
2860 * @param qstate: query state.
2861 * @param iq: iterator query state.
2862 * @param id: module id.
2863 * @return true if the event needs more processing, false if not. Since this
2864 * is the final state for an event, it always returns false.
2867 processFinished(struct module_qstate* qstate, struct iter_qstate* iq,
2870 log_query_info(VERB_QUERY, "finishing processing for",
2873 /* store negative cache element for parent side glue. */
2874 if(iq->query_for_pside_glue && !iq->pside_glue)
2875 iter_store_parentside_neg(qstate->env, &qstate->qinfo,
2876 iq->deleg_msg?iq->deleg_msg->rep:
2877 (iq->response?iq->response->rep:NULL));
2879 verbose(VERB_ALGO, "No response is set, servfail");
2880 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
2883 /* Make sure that the RA flag is set (since the presence of
2884 * this module means that recursion is available) */
2885 iq->response->rep->flags |= BIT_RA;
2887 /* Clear the AA flag */
2888 /* FIXME: does this action go here or in some other module? */
2889 iq->response->rep->flags &= ~BIT_AA;
2891 /* make sure QR flag is on */
2892 iq->response->rep->flags |= BIT_QR;
2894 /* we have finished processing this query */
2895 qstate->ext_state[id] = module_finished;
2897 /* TODO: we are using a private TTL, trim the response. */
2898 /* if (mPrivateTTL > 0){IterUtils.setPrivateTTL(resp, mPrivateTTL); } */
2900 /* prepend any items we have accumulated */
2901 if(iq->an_prepend_list || iq->ns_prepend_list) {
2902 if(!iter_prepend(iq, iq->response, qstate->region)) {
2903 log_err("prepend rrsets: out of memory");
2904 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
2906 /* reset the query name back */
2907 iq->response->qinfo = qstate->qinfo;
2908 /* the security state depends on the combination */
2909 iq->response->rep->security = sec_status_unchecked;
2910 /* store message with the finished prepended items,
2911 * but only if we did recursion. The nonrecursion referral
2912 * from cache does not need to be stored in the msg cache. */
2913 if(qstate->query_flags&BIT_RD) {
2914 iter_dns_store(qstate->env, &qstate->qinfo,
2915 iq->response->rep, 0, qstate->prefetch_leeway,
2916 iq->dp&&iq->dp->has_parent_side_NS,
2917 qstate->region, qstate->query_flags);
2920 qstate->return_rcode = LDNS_RCODE_NOERROR;
2921 qstate->return_msg = iq->response;
2926 * Return priming query results to interestes super querystates.
2928 * Sets the delegation point and delegation message (not nonRD queries).
2929 * This is a callback from walk_supers.
2931 * @param qstate: query state that finished.
2932 * @param id: module id.
2933 * @param super: the qstate to inform.
2936 iter_inform_super(struct module_qstate* qstate, int id,
2937 struct module_qstate* super)
2939 if(!qstate->is_priming && super->qinfo.qclass == LDNS_RR_CLASS_ANY)
2940 processClassResponse(qstate, id, super);
2941 else if(super->qinfo.qtype == LDNS_RR_TYPE_DS && ((struct iter_qstate*)
2942 super->minfo[id])->state == DSNS_FIND_STATE)
2943 processDSNSResponse(qstate, id, super);
2944 else if(qstate->return_rcode != LDNS_RCODE_NOERROR)
2945 error_supers(qstate, id, super);
2946 else if(qstate->is_priming)
2947 prime_supers(qstate, id, super);
2948 else processTargetResponse(qstate, id, super);
2952 * Handle iterator state.
2953 * Handle events. This is the real processing loop for events, responsible
2954 * for moving events through the various states. If a processing method
2955 * returns true, then it will be advanced to the next state. If false, then
2956 * processing will stop.
2958 * @param qstate: query state.
2959 * @param ie: iterator shared global environment.
2960 * @param iq: iterator query state.
2961 * @param id: module id.
2964 iter_handle(struct module_qstate* qstate, struct iter_qstate* iq,
2965 struct iter_env* ie, int id)
2969 verbose(VERB_ALGO, "iter_handle processing q with state %s",
2970 iter_state_to_string(iq->state));
2972 case INIT_REQUEST_STATE:
2973 cont = processInitRequest(qstate, iq, ie, id);
2975 case INIT_REQUEST_2_STATE:
2976 cont = processInitRequest2(qstate, iq, id);
2978 case INIT_REQUEST_3_STATE:
2979 cont = processInitRequest3(qstate, iq, id);
2981 case QUERYTARGETS_STATE:
2982 cont = processQueryTargets(qstate, iq, ie, id);
2984 case QUERY_RESP_STATE:
2985 cont = processQueryResponse(qstate, iq, id);
2987 case PRIME_RESP_STATE:
2988 cont = processPrimeResponse(qstate, id);
2990 case COLLECT_CLASS_STATE:
2991 cont = processCollectClass(qstate, id);
2993 case DSNS_FIND_STATE:
2994 cont = processDSNSFind(qstate, iq, id);
2996 case FINISHED_STATE:
2997 cont = processFinished(qstate, iq, id);
3000 log_warn("iterator: invalid state: %d",
3009 * This is the primary entry point for processing request events. Note that
3010 * this method should only be used by external modules.
3011 * @param qstate: query state.
3012 * @param ie: iterator shared global environment.
3013 * @param iq: iterator query state.
3014 * @param id: module id.
3017 process_request(struct module_qstate* qstate, struct iter_qstate* iq,
3018 struct iter_env* ie, int id)
3020 /* external requests start in the INIT state, and finish using the
3021 * FINISHED state. */
3022 iq->state = INIT_REQUEST_STATE;
3023 iq->final_state = FINISHED_STATE;
3024 verbose(VERB_ALGO, "process_request: new external request event");
3025 iter_handle(qstate, iq, ie, id);
3028 /** process authoritative server reply */
3030 process_response(struct module_qstate* qstate, struct iter_qstate* iq,
3031 struct iter_env* ie, int id, struct outbound_entry* outbound,
3032 enum module_ev event)
3034 struct msg_parse* prs;
3035 struct edns_data edns;
3038 verbose(VERB_ALGO, "process_response: new external response event");
3039 iq->response = NULL;
3040 iq->state = QUERY_RESP_STATE;
3041 if(event == module_event_noreply || event == module_event_error) {
3042 if(event == module_event_noreply && iq->sent_count >= 3 &&
3043 qstate->env->cfg->use_caps_bits_for_id &&
3044 !iq->caps_fallback) {
3045 /* start fallback */
3046 iq->caps_fallback = 1;
3047 iq->caps_server = 0;
3048 iq->caps_reply = NULL;
3049 iq->caps_response = NULL;
3050 iq->state = QUERYTARGETS_STATE;
3051 iq->num_current_queries--;
3052 /* need fresh attempts for the 0x20 fallback, if
3053 * that was the cause for the failure */
3054 iter_dec_attempts(iq->dp, 3);
3055 verbose(VERB_DETAIL, "Capsforid: timeouts, starting fallback");
3060 if( (event != module_event_reply && event != module_event_capsfail)
3061 || !qstate->reply) {
3062 log_err("Bad event combined with response");
3063 outbound_list_remove(&iq->outlist, outbound);
3064 (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL);
3069 prs = (struct msg_parse*)regional_alloc(qstate->env->scratch,
3070 sizeof(struct msg_parse));
3072 log_err("out of memory on incoming message");
3073 /* like packet got dropped */
3076 memset(prs, 0, sizeof(*prs));
3077 memset(&edns, 0, sizeof(edns));
3078 pkt = qstate->reply->c->buffer;
3079 sldns_buffer_set_position(pkt, 0);
3080 if(parse_packet(pkt, prs, qstate->env->scratch) != LDNS_RCODE_NOERROR) {
3081 verbose(VERB_ALGO, "parse error on reply packet");
3084 /* edns is not examined, but removed from message to help cache */
3085 if(parse_extract_edns(prs, &edns) != LDNS_RCODE_NOERROR)
3087 /* remove CD-bit, we asked for in case we handle validation ourself */
3088 prs->flags &= ~BIT_CD;
3090 /* normalize and sanitize: easy to delete items from linked lists */
3091 if(!scrub_message(pkt, prs, &iq->qinfo_out, iq->dp->name,
3092 qstate->env->scratch, qstate->env, ie)) {
3093 /* if 0x20 enabled, start fallback, but we have no message */
3094 if(event == module_event_capsfail && !iq->caps_fallback) {
3095 iq->caps_fallback = 1;
3096 iq->caps_server = 0;
3097 iq->caps_reply = NULL;
3098 iq->caps_response = NULL;
3099 iq->state = QUERYTARGETS_STATE;
3100 iq->num_current_queries--;
3101 verbose(VERB_DETAIL, "Capsforid: scrub failed, starting fallback with no response");
3106 /* allocate response dns_msg in region */
3107 iq->response = dns_alloc_msg(pkt, prs, qstate->region);
3110 log_query_info(VERB_DETAIL, "response for", &qstate->qinfo);
3111 log_name_addr(VERB_DETAIL, "reply from", iq->dp->name,
3112 &qstate->reply->addr, qstate->reply->addrlen);
3113 if(verbosity >= VERB_ALGO)
3114 log_dns_msg("incoming scrubbed packet:", &iq->response->qinfo,
3117 if(event == module_event_capsfail || iq->caps_fallback) {
3118 /* for fallback we care about main answer, not additionals */
3119 /* removing that makes comparison more likely to succeed */
3120 caps_strip_reply(iq->response->rep);
3121 if(!iq->caps_fallback) {
3122 /* start fallback */
3123 iq->caps_fallback = 1;
3124 iq->caps_server = 0;
3125 iq->caps_reply = iq->response->rep;
3126 iq->caps_response = iq->response;
3127 iq->state = QUERYTARGETS_STATE;
3128 iq->num_current_queries--;
3129 verbose(VERB_DETAIL, "Capsforid: starting fallback");
3132 /* check if reply is the same, otherwise, fail */
3133 if(!iq->caps_reply) {
3134 iq->caps_reply = iq->response->rep;
3135 iq->caps_response = iq->response;
3136 iq->caps_server = -1; /*become zero at ++,
3137 so that we start the full set of trials */
3138 } else if(caps_failed_rcode(iq->caps_reply) &&
3139 !caps_failed_rcode(iq->response->rep)) {
3140 /* prefer to upgrade to non-SERVFAIL */
3141 iq->caps_reply = iq->response->rep;
3142 iq->caps_response = iq->response;
3143 } else if(!caps_failed_rcode(iq->caps_reply) &&
3144 caps_failed_rcode(iq->response->rep)) {
3145 /* if we have non-SERVFAIL as answer then
3146 * we can ignore SERVFAILs for the equality
3148 /* no instructions here, skip other else */
3149 } else if(caps_failed_rcode(iq->caps_reply) &&
3150 caps_failed_rcode(iq->response->rep)) {
3151 /* failure is same as other failure in fallbk*/
3152 /* no instructions here, skip other else */
3153 } else if(!reply_equal(iq->response->rep, iq->caps_reply,
3154 qstate->env->scratch)) {
3155 verbose(VERB_DETAIL, "Capsforid fallback: "
3156 "getting different replies, failed");
3157 outbound_list_remove(&iq->outlist, outbound);
3158 (void)error_response(qstate, id,
3159 LDNS_RCODE_SERVFAIL);
3162 /* continue the fallback procedure at next server */
3164 iq->state = QUERYTARGETS_STATE;
3165 iq->num_current_queries--;
3166 verbose(VERB_DETAIL, "Capsforid: reply is equal. "
3167 "go to next fallback");
3171 iq->caps_fallback = 0; /* if we were in fallback, 0x20 is OK now */
3174 outbound_list_remove(&iq->outlist, outbound);
3175 iter_handle(qstate, iq, ie, id);
3179 iter_operate(struct module_qstate* qstate, enum module_ev event, int id,
3180 struct outbound_entry* outbound)
3182 struct iter_env* ie = (struct iter_env*)qstate->env->modinfo[id];
3183 struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id];
3184 verbose(VERB_QUERY, "iterator[module %d] operate: extstate:%s event:%s",
3185 id, strextstate(qstate->ext_state[id]), strmodulevent(event));
3186 if(iq) log_query_info(VERB_QUERY, "iterator operate: query",
3188 if(iq && qstate->qinfo.qname != iq->qchase.qname)
3189 log_query_info(VERB_QUERY, "iterator operate: chased to",
3192 /* perform iterator state machine */
3193 if((event == module_event_new || event == module_event_pass) &&
3195 if(!iter_new(qstate, id)) {
3196 (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL);
3199 iq = (struct iter_qstate*)qstate->minfo[id];
3200 process_request(qstate, iq, ie, id);
3203 if(iq && event == module_event_pass) {
3204 iter_handle(qstate, iq, ie, id);
3207 if(iq && outbound) {
3208 process_response(qstate, iq, ie, id, outbound, event);
3211 if(event == module_event_error) {
3212 verbose(VERB_ALGO, "got called with event error, giving up");
3213 (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL);
3217 log_err("bad event for iterator");
3218 (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL);
3222 iter_clear(struct module_qstate* qstate, int id)
3224 struct iter_qstate* iq;
3227 iq = (struct iter_qstate*)qstate->minfo[id];
3229 outbound_list_clear(&iq->outlist);
3230 if(iq->target_count && --iq->target_count[0] == 0)
3231 free(iq->target_count);
3232 iq->num_current_queries = 0;
3234 qstate->minfo[id] = NULL;
3238 iter_get_mem(struct module_env* env, int id)
3240 struct iter_env* ie = (struct iter_env*)env->modinfo[id];
3243 return sizeof(*ie) + sizeof(int)*((size_t)ie->max_dependency_depth+1)
3244 + donotq_get_mem(ie->donotq) + priv_get_mem(ie->priv);
3248 * The iterator function block
3250 static struct module_func_block iter_block = {
3252 &iter_init, &iter_deinit, &iter_operate, &iter_inform_super,
3253 &iter_clear, &iter_get_mem
3256 struct module_func_block*
3257 iter_get_funcblock(void)
3263 iter_state_to_string(enum iter_state state)
3267 case INIT_REQUEST_STATE :
3268 return "INIT REQUEST STATE";
3269 case INIT_REQUEST_2_STATE :
3270 return "INIT REQUEST STATE (stage 2)";
3271 case INIT_REQUEST_3_STATE:
3272 return "INIT REQUEST STATE (stage 3)";
3273 case QUERYTARGETS_STATE :
3274 return "QUERY TARGETS STATE";
3275 case PRIME_RESP_STATE :
3276 return "PRIME RESPONSE STATE";
3277 case COLLECT_CLASS_STATE :
3278 return "COLLECT CLASS STATE";
3279 case DSNS_FIND_STATE :
3280 return "DSNS FIND STATE";
3281 case QUERY_RESP_STATE :
3282 return "QUERY RESPONSE STATE";
3283 case FINISHED_STATE :
3284 return "FINISHED RESPONSE STATE";
3286 return "UNKNOWN ITER STATE";
3291 iter_state_is_responsestate(enum iter_state s)
3294 case INIT_REQUEST_STATE :
3295 case INIT_REQUEST_2_STATE :
3296 case INIT_REQUEST_3_STATE :
3297 case QUERYTARGETS_STATE :
3298 case COLLECT_CLASS_STATE :