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Diffstat (limited to 'external/unbound/iterator/iterator.c')
| -rw-r--r-- | external/unbound/iterator/iterator.c | 3432 |
1 files changed, 0 insertions, 3432 deletions
diff --git a/external/unbound/iterator/iterator.c b/external/unbound/iterator/iterator.c deleted file mode 100644 index 43b3d30c3..000000000 --- a/external/unbound/iterator/iterator.c +++ /dev/null @@ -1,3432 +0,0 @@ -/* - * iterator/iterator.c - iterative resolver DNS query response module - * - * Copyright (c) 2007, NLnet Labs. All rights reserved. - * - * This software is open source. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * - * Redistributions of source code must retain the above copyright notice, - * this list of conditions and the following disclaimer. - * - * Redistributions in binary form must reproduce the above copyright notice, - * this list of conditions and the following disclaimer in the documentation - * and/or other materials provided with the distribution. - * - * Neither the name of the NLNET LABS nor the names of its contributors may - * be used to endorse or promote products derived from this software without - * specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR - * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT - * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, - * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED - * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR - * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF - * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING - * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS - * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - */ - -/** - * \file - * - * This file contains a module that performs recusive iterative DNS query - * processing. - */ - -#include "config.h" -#include "iterator/iterator.h" -#include "iterator/iter_utils.h" -#include "iterator/iter_hints.h" -#include "iterator/iter_fwd.h" -#include "iterator/iter_donotq.h" -#include "iterator/iter_delegpt.h" -#include "iterator/iter_resptype.h" -#include "iterator/iter_scrub.h" -#include "iterator/iter_priv.h" -#include "validator/val_neg.h" -#include "services/cache/dns.h" -#include "services/cache/infra.h" -#include "util/module.h" -#include "util/netevent.h" -#include "util/net_help.h" -#include "util/regional.h" -#include "util/data/dname.h" -#include "util/data/msgencode.h" -#include "util/fptr_wlist.h" -#include "util/config_file.h" -#include "util/random.h" -#include "sldns/rrdef.h" -#include "sldns/wire2str.h" -#include "sldns/str2wire.h" -#include "sldns/parseutil.h" -#include "sldns/sbuffer.h" - -int -iter_init(struct module_env* env, int id) -{ - struct iter_env* iter_env = (struct iter_env*)calloc(1, - sizeof(struct iter_env)); - if(!iter_env) { - log_err("malloc failure"); - return 0; - } - env->modinfo[id] = (void*)iter_env; - if(!iter_apply_cfg(iter_env, env->cfg)) { - log_err("iterator: could not apply configuration settings."); - return 0; - } - - return 1; -} - -/** delete caps_whitelist element */ -static void -caps_free(struct rbnode_type* n, void* ATTR_UNUSED(d)) -{ - if(n) { - free(((struct name_tree_node*)n)->name); - free(n); - } -} - -void -iter_deinit(struct module_env* env, int id) -{ - struct iter_env* iter_env; - if(!env || !env->modinfo[id]) - return; - iter_env = (struct iter_env*)env->modinfo[id]; - free(iter_env->target_fetch_policy); - priv_delete(iter_env->priv); - donotq_delete(iter_env->donotq); - if(iter_env->caps_white) { - traverse_postorder(iter_env->caps_white, caps_free, NULL); - free(iter_env->caps_white); - } - free(iter_env); - env->modinfo[id] = NULL; -} - -/** new query for iterator */ -static int -iter_new(struct module_qstate* qstate, int id) -{ - struct iter_qstate* iq = (struct iter_qstate*)regional_alloc( - qstate->region, sizeof(struct iter_qstate)); - qstate->minfo[id] = iq; - if(!iq) - return 0; - memset(iq, 0, sizeof(*iq)); - iq->state = INIT_REQUEST_STATE; - iq->final_state = FINISHED_STATE; - iq->an_prepend_list = NULL; - iq->an_prepend_last = NULL; - iq->ns_prepend_list = NULL; - iq->ns_prepend_last = NULL; - iq->dp = NULL; - iq->depth = 0; - iq->num_target_queries = 0; - iq->num_current_queries = 0; - iq->query_restart_count = 0; - iq->referral_count = 0; - iq->sent_count = 0; - iq->ratelimit_ok = 0; - iq->target_count = NULL; - iq->wait_priming_stub = 0; - iq->refetch_glue = 0; - iq->dnssec_expected = 0; - iq->dnssec_lame_query = 0; - iq->chase_flags = qstate->query_flags; - /* Start with the (current) qname. */ - iq->qchase = qstate->qinfo; - outbound_list_init(&iq->outlist); - iq->minimise_count = 0; - iq->minimise_timeout_count = 0; - if (qstate->env->cfg->qname_minimisation) - iq->minimisation_state = INIT_MINIMISE_STATE; - else - iq->minimisation_state = DONOT_MINIMISE_STATE; - - memset(&iq->qinfo_out, 0, sizeof(struct query_info)); - return 1; -} - -/** - * Transition to the next state. This can be used to advance a currently - * processing event. It cannot be used to reactivate a forEvent. - * - * @param iq: iterator query state - * @param nextstate The state to transition to. - * @return true. This is so this can be called as the return value for the - * actual process*State() methods. (Transitioning to the next state - * implies further processing). - */ -static int -next_state(struct iter_qstate* iq, enum iter_state nextstate) -{ - /* If transitioning to a "response" state, make sure that there is a - * response */ - if(iter_state_is_responsestate(nextstate)) { - if(iq->response == NULL) { - log_err("transitioning to response state sans " - "response."); - } - } - iq->state = nextstate; - return 1; -} - -/** - * Transition an event to its final state. Final states always either return - * a result up the module chain, or reactivate a dependent event. Which - * final state to transition to is set in the module state for the event when - * it was created, and depends on the original purpose of the event. - * - * The response is stored in the qstate->buf buffer. - * - * @param iq: iterator query state - * @return false. This is so this method can be used as the return value for - * the processState methods. (Transitioning to the final state - */ -static int -final_state(struct iter_qstate* iq) -{ - return next_state(iq, iq->final_state); -} - -/** - * Callback routine to handle errors in parent query states - * @param qstate: query state that failed. - * @param id: module id. - * @param super: super state. - */ -static void -error_supers(struct module_qstate* qstate, int id, struct module_qstate* super) -{ - struct iter_qstate* super_iq = (struct iter_qstate*)super->minfo[id]; - - if(qstate->qinfo.qtype == LDNS_RR_TYPE_A || - qstate->qinfo.qtype == LDNS_RR_TYPE_AAAA) { - /* mark address as failed. */ - struct delegpt_ns* dpns = NULL; - super_iq->num_target_queries--; - if(super_iq->dp) - dpns = delegpt_find_ns(super_iq->dp, - qstate->qinfo.qname, qstate->qinfo.qname_len); - if(!dpns) { - /* not interested */ - verbose(VERB_ALGO, "subq error, but not interested"); - log_query_info(VERB_ALGO, "superq", &super->qinfo); - if(super_iq->dp) - delegpt_log(VERB_ALGO, super_iq->dp); - log_assert(0); - return; - } else { - /* see if the failure did get (parent-lame) info */ - if(!cache_fill_missing(super->env, super_iq->qchase.qclass, - super->region, super_iq->dp)) - log_err("out of memory adding missing"); - } - dpns->resolved = 1; /* mark as failed */ - } - if(qstate->qinfo.qtype == LDNS_RR_TYPE_NS) { - /* prime failed to get delegation */ - super_iq->dp = NULL; - } - /* evaluate targets again */ - super_iq->state = QUERYTARGETS_STATE; - /* super becomes runnable, and will process this change */ -} - -/** - * Return an error to the client - * @param qstate: our query state - * @param id: module id - * @param rcode: error code (DNS errcode). - * @return: 0 for use by caller, to make notation easy, like: - * return error_response(..). - */ -static int -error_response(struct module_qstate* qstate, int id, int rcode) -{ - verbose(VERB_QUERY, "return error response %s", - sldns_lookup_by_id(sldns_rcodes, rcode)? - sldns_lookup_by_id(sldns_rcodes, rcode)->name:"??"); - qstate->return_rcode = rcode; - qstate->return_msg = NULL; - qstate->ext_state[id] = module_finished; - return 0; -} - -/** - * Return an error to the client and cache the error code in the - * message cache (so per qname, qtype, qclass). - * @param qstate: our query state - * @param id: module id - * @param rcode: error code (DNS errcode). - * @return: 0 for use by caller, to make notation easy, like: - * return error_response(..). - */ -static int -error_response_cache(struct module_qstate* qstate, int id, int rcode) -{ - if(!qstate->no_cache_store) { - /* store in cache */ - struct reply_info err; - if(qstate->prefetch_leeway > NORR_TTL) { - verbose(VERB_ALGO, "error response for prefetch in cache"); - /* attempt to adjust the cache entry prefetch */ - if(dns_cache_prefetch_adjust(qstate->env, &qstate->qinfo, - NORR_TTL, qstate->query_flags)) - return error_response(qstate, id, rcode); - /* if that fails (not in cache), fall through to store err */ - } - memset(&err, 0, sizeof(err)); - err.flags = (uint16_t)(BIT_QR | BIT_RA); - FLAGS_SET_RCODE(err.flags, rcode); - err.qdcount = 1; - err.ttl = NORR_TTL; - err.prefetch_ttl = PREFETCH_TTL_CALC(err.ttl); - /* do not waste time trying to validate this servfail */ - err.security = sec_status_indeterminate; - verbose(VERB_ALGO, "store error response in message cache"); - iter_dns_store(qstate->env, &qstate->qinfo, &err, 0, 0, 0, NULL, - qstate->query_flags); - } - return error_response(qstate, id, rcode); -} - -/** check if prepend item is duplicate item */ -static int -prepend_is_duplicate(struct ub_packed_rrset_key** sets, size_t to, - struct ub_packed_rrset_key* dup) -{ - size_t i; - for(i=0; i<to; i++) { - if(sets[i]->rk.type == dup->rk.type && - sets[i]->rk.rrset_class == dup->rk.rrset_class && - sets[i]->rk.dname_len == dup->rk.dname_len && - query_dname_compare(sets[i]->rk.dname, dup->rk.dname) - == 0) - return 1; - } - return 0; -} - -/** prepend the prepend list in the answer and authority section of dns_msg */ -static int -iter_prepend(struct iter_qstate* iq, struct dns_msg* msg, - struct regional* region) -{ - struct iter_prep_list* p; - struct ub_packed_rrset_key** sets; - size_t num_an = 0, num_ns = 0;; - for(p = iq->an_prepend_list; p; p = p->next) - num_an++; - for(p = iq->ns_prepend_list; p; p = p->next) - num_ns++; - if(num_an + num_ns == 0) - return 1; - verbose(VERB_ALGO, "prepending %d rrsets", (int)num_an + (int)num_ns); - if(num_an > RR_COUNT_MAX || num_ns > RR_COUNT_MAX || - msg->rep->rrset_count > RR_COUNT_MAX) return 0; /* overflow */ - sets = regional_alloc(region, (num_an+num_ns+msg->rep->rrset_count) * - sizeof(struct ub_packed_rrset_key*)); - if(!sets) - return 0; - /* ANSWER section */ - num_an = 0; - for(p = iq->an_prepend_list; p; p = p->next) { - sets[num_an++] = p->rrset; - } - memcpy(sets+num_an, msg->rep->rrsets, msg->rep->an_numrrsets * - sizeof(struct ub_packed_rrset_key*)); - /* AUTH section */ - num_ns = 0; - for(p = iq->ns_prepend_list; p; p = p->next) { - if(prepend_is_duplicate(sets+msg->rep->an_numrrsets+num_an, - num_ns, p->rrset) || prepend_is_duplicate( - msg->rep->rrsets+msg->rep->an_numrrsets, - msg->rep->ns_numrrsets, p->rrset)) - continue; - sets[msg->rep->an_numrrsets + num_an + num_ns++] = p->rrset; - } - memcpy(sets + num_an + msg->rep->an_numrrsets + num_ns, - msg->rep->rrsets + msg->rep->an_numrrsets, - (msg->rep->ns_numrrsets + msg->rep->ar_numrrsets) * - sizeof(struct ub_packed_rrset_key*)); - - /* NXDOMAIN rcode can stay if we prepended DNAME/CNAMEs, because - * this is what recursors should give. */ - msg->rep->rrset_count += num_an + num_ns; - msg->rep->an_numrrsets += num_an; - msg->rep->ns_numrrsets += num_ns; - msg->rep->rrsets = sets; - return 1; -} - -/** - * Find rrset in ANSWER prepend list. - * to avoid duplicate DNAMEs when a DNAME is traversed twice. - * @param iq: iterator query state. - * @param rrset: rrset to add. - * @return false if not found - */ -static int -iter_find_rrset_in_prepend_answer(struct iter_qstate* iq, - struct ub_packed_rrset_key* rrset) -{ - struct iter_prep_list* p = iq->an_prepend_list; - while(p) { - if(ub_rrset_compare(p->rrset, rrset) == 0 && - rrsetdata_equal((struct packed_rrset_data*)p->rrset - ->entry.data, (struct packed_rrset_data*)rrset - ->entry.data)) - return 1; - p = p->next; - } - return 0; -} - -/** - * Add rrset to ANSWER prepend list - * @param qstate: query state. - * @param iq: iterator query state. - * @param rrset: rrset to add. - * @return false on failure (malloc). - */ -static int -iter_add_prepend_answer(struct module_qstate* qstate, struct iter_qstate* iq, - struct ub_packed_rrset_key* rrset) -{ - struct iter_prep_list* p = (struct iter_prep_list*)regional_alloc( - qstate->region, sizeof(struct iter_prep_list)); - if(!p) - return 0; - p->rrset = rrset; - p->next = NULL; - /* add at end */ - if(iq->an_prepend_last) - iq->an_prepend_last->next = p; - else iq->an_prepend_list = p; - iq->an_prepend_last = p; - return 1; -} - -/** - * Add rrset to AUTHORITY prepend list - * @param qstate: query state. - * @param iq: iterator query state. - * @param rrset: rrset to add. - * @return false on failure (malloc). - */ -static int -iter_add_prepend_auth(struct module_qstate* qstate, struct iter_qstate* iq, - struct ub_packed_rrset_key* rrset) -{ - struct iter_prep_list* p = (struct iter_prep_list*)regional_alloc( - qstate->region, sizeof(struct iter_prep_list)); - if(!p) - return 0; - p->rrset = rrset; - p->next = NULL; - /* add at end */ - if(iq->ns_prepend_last) - iq->ns_prepend_last->next = p; - else iq->ns_prepend_list = p; - iq->ns_prepend_last = p; - return 1; -} - -/** - * Given a CNAME response (defined as a response containing a CNAME or DNAME - * that does not answer the request), process the response, modifying the - * state as necessary. This follows the CNAME/DNAME chain and returns the - * final query name. - * - * sets the new query name, after following the CNAME/DNAME chain. - * @param qstate: query state. - * @param iq: iterator query state. - * @param msg: the response. - * @param mname: returned target new query name. - * @param mname_len: length of mname. - * @return false on (malloc) error. - */ -static int -handle_cname_response(struct module_qstate* qstate, struct iter_qstate* iq, - struct dns_msg* msg, uint8_t** mname, size_t* mname_len) -{ - size_t i; - /* Start with the (current) qname. */ - *mname = iq->qchase.qname; - *mname_len = iq->qchase.qname_len; - - /* Iterate over the ANSWER rrsets in order, looking for CNAMEs and - * DNAMES. */ - for(i=0; i<msg->rep->an_numrrsets; i++) { - struct ub_packed_rrset_key* r = msg->rep->rrsets[i]; - /* If there is a (relevant) DNAME, add it to the list. - * We always expect there to be CNAME that was generated - * by this DNAME following, so we don't process the DNAME - * directly. */ - if(ntohs(r->rk.type) == LDNS_RR_TYPE_DNAME && - dname_strict_subdomain_c(*mname, r->rk.dname) && - !iter_find_rrset_in_prepend_answer(iq, r)) { - if(!iter_add_prepend_answer(qstate, iq, r)) - return 0; - continue; - } - - if(ntohs(r->rk.type) == LDNS_RR_TYPE_CNAME && - query_dname_compare(*mname, r->rk.dname) == 0 && - !iter_find_rrset_in_prepend_answer(iq, r)) { - /* Add this relevant CNAME rrset to the prepend list.*/ - if(!iter_add_prepend_answer(qstate, iq, r)) - return 0; - get_cname_target(r, mname, mname_len); - } - - /* Other rrsets in the section are ignored. */ - } - /* add authority rrsets to authority prepend, for wildcarded CNAMEs */ - for(i=msg->rep->an_numrrsets; i<msg->rep->an_numrrsets + - msg->rep->ns_numrrsets; i++) { - struct ub_packed_rrset_key* r = msg->rep->rrsets[i]; - /* only add NSEC/NSEC3, as they may be needed for validation */ - if(ntohs(r->rk.type) == LDNS_RR_TYPE_NSEC || - ntohs(r->rk.type) == LDNS_RR_TYPE_NSEC3) { - if(!iter_add_prepend_auth(qstate, iq, r)) - return 0; - } - } - return 1; -} - -/** see if target name is caps-for-id whitelisted */ -static int -is_caps_whitelisted(struct iter_env* ie, struct iter_qstate* iq) -{ - if(!ie->caps_white) return 0; /* no whitelist, or no capsforid */ - return name_tree_lookup(ie->caps_white, iq->qchase.qname, - iq->qchase.qname_len, dname_count_labels(iq->qchase.qname), - iq->qchase.qclass) != NULL; -} - -/** create target count structure for this query */ -static void -target_count_create(struct iter_qstate* iq) -{ - if(!iq->target_count) { - iq->target_count = (int*)calloc(2, sizeof(int)); - /* if calloc fails we simply do not track this number */ - if(iq->target_count) - iq->target_count[0] = 1; - } -} - -static void -target_count_increase(struct iter_qstate* iq, int num) -{ - target_count_create(iq); - if(iq->target_count) - iq->target_count[1] += num; -} - -/** - * Generate a subrequest. - * Generate a local request event. Local events are tied to this module, and - * have a corresponding (first tier) event that is waiting for this event to - * resolve to continue. - * - * @param qname The query name for this request. - * @param qnamelen length of qname - * @param qtype The query type for this request. - * @param qclass The query class for this request. - * @param qstate The event that is generating this event. - * @param id: module id. - * @param iq: The iterator state that is generating this event. - * @param initial_state The initial response state (normally this - * is QUERY_RESP_STATE, unless it is known that the request won't - * need iterative processing - * @param finalstate The final state for the response to this request. - * @param subq_ret: if newly allocated, the subquerystate, or NULL if it does - * not need initialisation. - * @param v: if true, validation is done on the subquery. - * @return false on error (malloc). - */ -static int -generate_sub_request(uint8_t* qname, size_t qnamelen, uint16_t qtype, - uint16_t qclass, struct module_qstate* qstate, int id, - struct iter_qstate* iq, enum iter_state initial_state, - enum iter_state finalstate, struct module_qstate** subq_ret, int v) -{ - struct module_qstate* subq = NULL; - struct iter_qstate* subiq = NULL; - uint16_t qflags = 0; /* OPCODE QUERY, no flags */ - struct query_info qinf; - int prime = (finalstate == PRIME_RESP_STATE)?1:0; - int valrec = 0; - qinf.qname = qname; - qinf.qname_len = qnamelen; - qinf.qtype = qtype; - qinf.qclass = qclass; - qinf.local_alias = NULL; - - /* RD should be set only when sending the query back through the INIT - * state. */ - if(initial_state == INIT_REQUEST_STATE) - qflags |= BIT_RD; - /* We set the CD flag so we can send this through the "head" of - * the resolution chain, which might have a validator. We are - * uninterested in validating things not on the direct resolution - * path. */ - if(!v) { - qflags |= BIT_CD; - valrec = 1; - } - - /* attach subquery, lookup existing or make a new one */ - fptr_ok(fptr_whitelist_modenv_attach_sub(qstate->env->attach_sub)); - if(!(*qstate->env->attach_sub)(qstate, &qinf, qflags, prime, valrec, - &subq)) { - return 0; - } - *subq_ret = subq; - if(subq) { - /* initialise the new subquery */ - subq->curmod = id; - subq->ext_state[id] = module_state_initial; - subq->minfo[id] = regional_alloc(subq->region, - sizeof(struct iter_qstate)); - if(!subq->minfo[id]) { - log_err("init subq: out of memory"); - fptr_ok(fptr_whitelist_modenv_kill_sub( - qstate->env->kill_sub)); - (*qstate->env->kill_sub)(subq); - return 0; - } - subiq = (struct iter_qstate*)subq->minfo[id]; - memset(subiq, 0, sizeof(*subiq)); - subiq->num_target_queries = 0; - target_count_create(iq); - subiq->target_count = iq->target_count; - if(iq->target_count) - iq->target_count[0] ++; /* extra reference */ - subiq->num_current_queries = 0; - subiq->depth = iq->depth+1; - outbound_list_init(&subiq->outlist); - subiq->state = initial_state; - subiq->final_state = finalstate; - subiq->qchase = subq->qinfo; - subiq->chase_flags = subq->query_flags; - subiq->refetch_glue = 0; - if(qstate->env->cfg->qname_minimisation) - subiq->minimisation_state = INIT_MINIMISE_STATE; - else - subiq->minimisation_state = DONOT_MINIMISE_STATE; - memset(&subiq->qinfo_out, 0, sizeof(struct query_info)); - } - return 1; -} - -/** - * Generate and send a root priming request. - * @param qstate: the qtstate that triggered the need to prime. - * @param iq: iterator query state. - * @param id: module id. - * @param qclass: the class to prime. - * @return 0 on failure - */ -static int -prime_root(struct module_qstate* qstate, struct iter_qstate* iq, int id, - uint16_t qclass) -{ - struct delegpt* dp; - struct module_qstate* subq; - verbose(VERB_DETAIL, "priming . %s NS", - sldns_lookup_by_id(sldns_rr_classes, (int)qclass)? - sldns_lookup_by_id(sldns_rr_classes, (int)qclass)->name:"??"); - dp = hints_lookup_root(qstate->env->hints, qclass); - if(!dp) { - verbose(VERB_ALGO, "Cannot prime due to lack of hints"); - return 0; - } - /* Priming requests start at the QUERYTARGETS state, skipping - * the normal INIT state logic (which would cause an infloop). */ - if(!generate_sub_request((uint8_t*)"\000", 1, LDNS_RR_TYPE_NS, - qclass, qstate, id, iq, QUERYTARGETS_STATE, PRIME_RESP_STATE, - &subq, 0)) { - verbose(VERB_ALGO, "could not prime root"); - return 0; - } - if(subq) { - struct iter_qstate* subiq = - (struct iter_qstate*)subq->minfo[id]; - /* Set the initial delegation point to the hint. - * copy dp, it is now part of the root prime query. - * dp was part of in the fixed hints structure. */ - subiq->dp = delegpt_copy(dp, subq->region); - if(!subiq->dp) { - log_err("out of memory priming root, copydp"); - fptr_ok(fptr_whitelist_modenv_kill_sub( - qstate->env->kill_sub)); - (*qstate->env->kill_sub)(subq); - return 0; - } - /* there should not be any target queries. */ - subiq->num_target_queries = 0; - subiq->dnssec_expected = iter_indicates_dnssec( - qstate->env, subiq->dp, NULL, subq->qinfo.qclass); - } - - /* this module stops, our submodule starts, and does the query. */ - qstate->ext_state[id] = module_wait_subquery; - return 1; -} - -/** - * Generate and process a stub priming request. This method tests for the - * need to prime a stub zone, so it is safe to call for every request. - * - * @param qstate: the qtstate that triggered the need to prime. - * @param iq: iterator query state. - * @param id: module id. - * @param qname: request name. - * @param qclass: request class. - * @return true if a priming subrequest was made, false if not. The will only - * issue a priming request if it detects an unprimed stub. - * Uses value of 2 to signal during stub-prime in root-prime situation - * that a noprime-stub is available and resolution can continue. - */ -static int -prime_stub(struct module_qstate* qstate, struct iter_qstate* iq, int id, - uint8_t* qname, uint16_t qclass) -{ - /* Lookup the stub hint. This will return null if the stub doesn't - * need to be re-primed. */ - struct iter_hints_stub* stub; - struct delegpt* stub_dp; - struct module_qstate* subq; - - if(!qname) return 0; - stub = hints_lookup_stub(qstate->env->hints, qname, qclass, iq->dp); - /* The stub (if there is one) does not need priming. */ - if(!stub) - return 0; - stub_dp = stub->dp; - - /* is it a noprime stub (always use) */ - if(stub->noprime) { - int r = 0; - if(iq->dp == NULL) r = 2; - /* copy the dp out of the fixed hints structure, so that - * it can be changed when servicing this query */ - iq->dp = delegpt_copy(stub_dp, qstate->region); - if(!iq->dp) { - log_err("out of memory priming stub"); - (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL); - return 1; /* return 1 to make module stop, with error */ - } - log_nametypeclass(VERB_DETAIL, "use stub", stub_dp->name, - LDNS_RR_TYPE_NS, qclass); - return r; - } - - /* Otherwise, we need to (re)prime the stub. */ - log_nametypeclass(VERB_DETAIL, "priming stub", stub_dp->name, - LDNS_RR_TYPE_NS, qclass); - - /* Stub priming events start at the QUERYTARGETS state to avoid the - * redundant INIT state processing. */ - if(!generate_sub_request(stub_dp->name, stub_dp->namelen, - LDNS_RR_TYPE_NS, qclass, qstate, id, iq, - QUERYTARGETS_STATE, PRIME_RESP_STATE, &subq, 0)) { - verbose(VERB_ALGO, "could not prime stub"); - (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL); - return 1; /* return 1 to make module stop, with error */ - } - if(subq) { - struct iter_qstate* subiq = - (struct iter_qstate*)subq->minfo[id]; - - /* Set the initial delegation point to the hint. */ - /* make copy to avoid use of stub dp by different qs/threads */ - subiq->dp = delegpt_copy(stub_dp, subq->region); - if(!subiq->dp) { - log_err("out of memory priming stub, copydp"); - fptr_ok(fptr_whitelist_modenv_kill_sub( - qstate->env->kill_sub)); - (*qstate->env->kill_sub)(subq); - (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL); - return 1; /* return 1 to make module stop, with error */ - } - /* there should not be any target queries -- although there - * wouldn't be anyway, since stub hints never have - * missing targets. */ - subiq->num_target_queries = 0; - subiq->wait_priming_stub = 1; - subiq->dnssec_expected = iter_indicates_dnssec( - qstate->env, subiq->dp, NULL, subq->qinfo.qclass); - } - - /* this module stops, our submodule starts, and does the query. */ - qstate->ext_state[id] = module_wait_subquery; - return 1; -} - -/** - * Generate A and AAAA checks for glue that is in-zone for the referral - * we just got to obtain authoritative information on the adresses. - * - * @param qstate: the qtstate that triggered the need to prime. - * @param iq: iterator query state. - * @param id: module id. - */ -static void -generate_a_aaaa_check(struct module_qstate* qstate, struct iter_qstate* iq, - int id) -{ - struct iter_env* ie = (struct iter_env*)qstate->env->modinfo[id]; - struct module_qstate* subq; - size_t i; - struct reply_info* rep = iq->response->rep; - struct ub_packed_rrset_key* s; - log_assert(iq->dp); - - if(iq->depth == ie->max_dependency_depth) - return; - /* walk through additional, and check if in-zone, - * only relevant A, AAAA are left after scrub anyway */ - for(i=rep->an_numrrsets+rep->ns_numrrsets; i<rep->rrset_count; i++) { - s = rep->rrsets[i]; - /* check *ALL* addresses that are transmitted in additional*/ - /* is it an address ? */ - if( !(ntohs(s->rk.type)==LDNS_RR_TYPE_A || - ntohs(s->rk.type)==LDNS_RR_TYPE_AAAA)) { - continue; - } - /* is this query the same as the A/AAAA check for it */ - if(qstate->qinfo.qtype == ntohs(s->rk.type) && - qstate->qinfo.qclass == ntohs(s->rk.rrset_class) && - query_dname_compare(qstate->qinfo.qname, - s->rk.dname)==0 && - (qstate->query_flags&BIT_RD) && - !(qstate->query_flags&BIT_CD)) - continue; - - /* generate subrequest for it */ - log_nametypeclass(VERB_ALGO, "schedule addr fetch", - s->rk.dname, ntohs(s->rk.type), - ntohs(s->rk.rrset_class)); - if(!generate_sub_request(s->rk.dname, s->rk.dname_len, - ntohs(s->rk.type), ntohs(s->rk.rrset_class), - qstate, id, iq, - INIT_REQUEST_STATE, FINISHED_STATE, &subq, 1)) { - verbose(VERB_ALGO, "could not generate addr check"); - return; - } - /* ignore subq - not need for more init */ - } -} - -/** - * Generate a NS check request to obtain authoritative information - * on an NS rrset. - * - * @param qstate: the qtstate that triggered the need to prime. - * @param iq: iterator query state. - * @param id: module id. - */ -static void -generate_ns_check(struct module_qstate* qstate, struct iter_qstate* iq, int id) -{ - struct iter_env* ie = (struct iter_env*)qstate->env->modinfo[id]; - struct module_qstate* subq; - log_assert(iq->dp); - - if(iq->depth == ie->max_dependency_depth) - return; - /* is this query the same as the nscheck? */ - if(qstate->qinfo.qtype == LDNS_RR_TYPE_NS && - query_dname_compare(iq->dp->name, qstate->qinfo.qname)==0 && - (qstate->query_flags&BIT_RD) && !(qstate->query_flags&BIT_CD)){ - /* spawn off A, AAAA queries for in-zone glue to check */ - generate_a_aaaa_check(qstate, iq, id); - return; - } - - log_nametypeclass(VERB_ALGO, "schedule ns fetch", - iq->dp->name, LDNS_RR_TYPE_NS, iq->qchase.qclass); - if(!generate_sub_request(iq->dp->name, iq->dp->namelen, - LDNS_RR_TYPE_NS, iq->qchase.qclass, qstate, id, iq, - INIT_REQUEST_STATE, FINISHED_STATE, &subq, 1)) { - verbose(VERB_ALGO, "could not generate ns check"); - return; - } - if(subq) { - struct iter_qstate* subiq = - (struct iter_qstate*)subq->minfo[id]; - - /* make copy to avoid use of stub dp by different qs/threads */ - /* refetch glue to start higher up the tree */ - subiq->refetch_glue = 1; - subiq->dp = delegpt_copy(iq->dp, subq->region); - if(!subiq->dp) { - log_err("out of memory generating ns check, copydp"); - fptr_ok(fptr_whitelist_modenv_kill_sub( - qstate->env->kill_sub)); - (*qstate->env->kill_sub)(subq); - return; - } - } -} - -/** - * Generate a DNSKEY prefetch query to get the DNSKEY for the DS record we - * just got in a referral (where we have dnssec_expected, thus have trust - * anchors above it). Note that right after calling this routine the - * iterator detached subqueries (because of following the referral), and thus - * the DNSKEY query becomes detached, its return stored in the cache for - * later lookup by the validator. This cache lookup by the validator avoids - * the roundtrip incurred by the DNSKEY query. The DNSKEY query is now - * performed at about the same time the original query is sent to the domain, - * thus the two answers are likely to be returned at about the same time, - * saving a roundtrip from the validated lookup. - * - * @param qstate: the qtstate that triggered the need to prime. - * @param iq: iterator query state. - * @param id: module id. - */ -static void -generate_dnskey_prefetch(struct module_qstate* qstate, - struct iter_qstate* iq, int id) -{ - struct module_qstate* subq; - log_assert(iq->dp); - - /* is this query the same as the prefetch? */ - if(qstate->qinfo.qtype == LDNS_RR_TYPE_DNSKEY && - query_dname_compare(iq->dp->name, qstate->qinfo.qname)==0 && - (qstate->query_flags&BIT_RD) && !(qstate->query_flags&BIT_CD)){ - return; - } - - /* if the DNSKEY is in the cache this lookup will stop quickly */ - log_nametypeclass(VERB_ALGO, "schedule dnskey prefetch", - iq->dp->name, LDNS_RR_TYPE_DNSKEY, iq->qchase.qclass); - if(!generate_sub_request(iq->dp->name, iq->dp->namelen, - LDNS_RR_TYPE_DNSKEY, iq->qchase.qclass, qstate, id, iq, - INIT_REQUEST_STATE, FINISHED_STATE, &subq, 0)) { - /* we'll be slower, but it'll work */ - verbose(VERB_ALGO, "could not generate dnskey prefetch"); - return; - } - if(subq) { - struct iter_qstate* subiq = - (struct iter_qstate*)subq->minfo[id]; - /* this qstate has the right delegation for the dnskey lookup*/ - /* make copy to avoid use of stub dp by different qs/threads */ - subiq->dp = delegpt_copy(iq->dp, subq->region); - /* if !subiq->dp, it'll start from the cache, no problem */ - } -} - -/** - * See if the query needs forwarding. - * - * @param qstate: query state. - * @param iq: iterator query state. - * @return true if the request is forwarded, false if not. - * If returns true but, iq->dp is NULL then a malloc failure occurred. - */ -static int -forward_request(struct module_qstate* qstate, struct iter_qstate* iq) -{ - struct delegpt* dp; - uint8_t* delname = iq->qchase.qname; - size_t delnamelen = iq->qchase.qname_len; - if(iq->refetch_glue) { - delname = iq->dp->name; - delnamelen = iq->dp->namelen; - } - /* strip one label off of DS query to lookup higher for it */ - if( (iq->qchase.qtype == LDNS_RR_TYPE_DS || iq->refetch_glue) - && !dname_is_root(iq->qchase.qname)) - dname_remove_label(&delname, &delnamelen); - dp = forwards_lookup(qstate->env->fwds, delname, iq->qchase.qclass); - if(!dp) - return 0; - /* send recursion desired to forward addr */ - iq->chase_flags |= BIT_RD; - iq->dp = delegpt_copy(dp, qstate->region); - /* iq->dp checked by caller */ - verbose(VERB_ALGO, "forwarding request"); - return 1; -} - -/** - * Process the initial part of the request handling. This state roughly - * corresponds to resolver algorithms steps 1 (find answer in cache) and 2 - * (find the best servers to ask). - * - * Note that all requests start here, and query restarts revisit this state. - * - * This state either generates: 1) a response, from cache or error, 2) a - * priming event, or 3) forwards the request to the next state (init2, - * generally). - * - * @param qstate: query state. - * @param iq: iterator query state. - * @param ie: iterator shared global environment. - * @param id: module id. - * @return true if the event needs more request processing immediately, - * false if not. - */ -static int -processInitRequest(struct module_qstate* qstate, struct iter_qstate* iq, - struct iter_env* ie, int id) -{ - uint8_t* delname; - size_t delnamelen; - struct dns_msg* msg = NULL; - - log_query_info(VERB_DETAIL, "resolving", &qstate->qinfo); - /* check effort */ - - /* We enforce a maximum number of query restarts. This is primarily a - * cheap way to prevent CNAME loops. */ - if(iq->query_restart_count > MAX_RESTART_COUNT) { - verbose(VERB_QUERY, "request has exceeded the maximum number" - " of query restarts with %d", iq->query_restart_count); - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - } - - /* We enforce a maximum recursion/dependency depth -- in general, - * this is unnecessary for dependency loops (although it will - * catch those), but it provides a sensible limit to the amount - * of work required to answer a given query. */ - verbose(VERB_ALGO, "request has dependency depth of %d", iq->depth); - if(iq->depth > ie->max_dependency_depth) { - verbose(VERB_QUERY, "request has exceeded the maximum " - "dependency depth with depth of %d", iq->depth); - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - } - - /* If the request is qclass=ANY, setup to generate each class */ - if(qstate->qinfo.qclass == LDNS_RR_CLASS_ANY) { - iq->qchase.qclass = 0; - return next_state(iq, COLLECT_CLASS_STATE); - } - - /* Resolver Algorithm Step 1 -- Look for the answer in local data. */ - - /* This either results in a query restart (CNAME cache response), a - * terminating response (ANSWER), or a cache miss (null). */ - - if(qstate->blacklist) { - /* if cache, or anything else, was blacklisted then - * getting older results from cache is a bad idea, no cache */ - verbose(VERB_ALGO, "cache blacklisted, going to the network"); - msg = NULL; - } else if(!qstate->no_cache_lookup) { - msg = dns_cache_lookup(qstate->env, iq->qchase.qname, - iq->qchase.qname_len, iq->qchase.qtype, - iq->qchase.qclass, qstate->query_flags, - qstate->region, qstate->env->scratch); - if(!msg && qstate->env->neg_cache) { - /* lookup in negative cache; may result in - * NOERROR/NODATA or NXDOMAIN answers that need validation */ - msg = val_neg_getmsg(qstate->env->neg_cache, &iq->qchase, - qstate->region, qstate->env->rrset_cache, - qstate->env->scratch_buffer, - *qstate->env->now, 1/*add SOA*/, NULL); - } - /* item taken from cache does not match our query name, thus - * security needs to be re-examined later */ - if(msg && query_dname_compare(qstate->qinfo.qname, - iq->qchase.qname) != 0) - msg->rep->security = sec_status_unchecked; - } - if(msg) { - /* handle positive cache response */ - enum response_type type = response_type_from_cache(msg, - &iq->qchase); - if(verbosity >= VERB_ALGO) { - log_dns_msg("msg from cache lookup", &msg->qinfo, - msg->rep); - verbose(VERB_ALGO, "msg ttl is %d, prefetch ttl %d", - (int)msg->rep->ttl, - (int)msg->rep->prefetch_ttl); - } - - if(type == RESPONSE_TYPE_CNAME) { - uint8_t* sname = 0; - size_t slen = 0; - verbose(VERB_ALGO, "returning CNAME response from " - "cache"); - if(!handle_cname_response(qstate, iq, msg, - &sname, &slen)) - return error_response(qstate, id, - LDNS_RCODE_SERVFAIL); - iq->qchase.qname = sname; - iq->qchase.qname_len = slen; - /* This *is* a query restart, even if it is a cheap - * one. */ - iq->dp = NULL; - iq->refetch_glue = 0; - iq->query_restart_count++; - iq->sent_count = 0; - sock_list_insert(&qstate->reply_origin, NULL, 0, qstate->region); - if(qstate->env->cfg->qname_minimisation) - iq->minimisation_state = INIT_MINIMISE_STATE; - return next_state(iq, INIT_REQUEST_STATE); - } - - /* if from cache, NULL, else insert 'cache IP' len=0 */ - if(qstate->reply_origin) - sock_list_insert(&qstate->reply_origin, NULL, 0, qstate->region); - /* it is an answer, response, to final state */ - verbose(VERB_ALGO, "returning answer from cache."); - iq->response = msg; - return final_state(iq); - } - - /* attempt to forward the request */ - if(forward_request(qstate, iq)) - { - if(!iq->dp) { - log_err("alloc failure for forward dp"); - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - } - iq->refetch_glue = 0; - iq->minimisation_state = DONOT_MINIMISE_STATE; - /* the request has been forwarded. - * forwarded requests need to be immediately sent to the - * next state, QUERYTARGETS. */ - return next_state(iq, QUERYTARGETS_STATE); - } - - /* Resolver Algorithm Step 2 -- find the "best" servers. */ - - /* first, adjust for DS queries. To avoid the grandparent problem, - * we just look for the closest set of server to the parent of qname. - * When re-fetching glue we also need to ask the parent. - */ - if(iq->refetch_glue) { - if(!iq->dp) { - log_err("internal or malloc fail: no dp for refetch"); - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - } - delname = iq->dp->name; - delnamelen = iq->dp->namelen; - } else { - delname = iq->qchase.qname; - delnamelen = iq->qchase.qname_len; - } - if(iq->qchase.qtype == LDNS_RR_TYPE_DS || iq->refetch_glue || - (iq->qchase.qtype == LDNS_RR_TYPE_NS && qstate->prefetch_leeway)) { - /* remove first label from delname, root goes to hints, - * but only to fetch glue, not for qtype=DS. */ - /* also when prefetching an NS record, fetch it again from - * its parent, just as if it expired, so that you do not - * get stuck on an older nameserver that gives old NSrecords */ - if(dname_is_root(delname) && (iq->refetch_glue || - (iq->qchase.qtype == LDNS_RR_TYPE_NS && - qstate->prefetch_leeway))) - delname = NULL; /* go to root priming */ - else dname_remove_label(&delname, &delnamelen); - } - /* delname is the name to lookup a delegation for. If NULL rootprime */ - while(1) { - - /* Lookup the delegation in the cache. If null, then the - * cache needs to be primed for the qclass. */ - if(delname) - iq->dp = dns_cache_find_delegation(qstate->env, delname, - delnamelen, iq->qchase.qtype, iq->qchase.qclass, - qstate->region, &iq->deleg_msg, - *qstate->env->now+qstate->prefetch_leeway); - else iq->dp = NULL; - - /* If the cache has returned nothing, then we have a - * root priming situation. */ - if(iq->dp == NULL) { - /* if there is a stub, then no root prime needed */ - int r = prime_stub(qstate, iq, id, delname, - iq->qchase.qclass); - if(r == 2) - break; /* got noprime-stub-zone, continue */ - else if(r) - return 0; /* stub prime request made */ - if(forwards_lookup_root(qstate->env->fwds, - iq->qchase.qclass)) { - /* forward zone root, no root prime needed */ - /* fill in some dp - safety belt */ - iq->dp = hints_lookup_root(qstate->env->hints, - iq->qchase.qclass); - if(!iq->dp) { - log_err("internal error: no hints dp"); - return error_response(qstate, id, - LDNS_RCODE_SERVFAIL); - } - iq->dp = delegpt_copy(iq->dp, qstate->region); - if(!iq->dp) { - log_err("out of memory in safety belt"); - return error_response(qstate, id, - LDNS_RCODE_SERVFAIL); - } - return next_state(iq, INIT_REQUEST_2_STATE); - } - /* Note that the result of this will set a new - * DelegationPoint based on the result of priming. */ - if(!prime_root(qstate, iq, id, iq->qchase.qclass)) - return error_response(qstate, id, - LDNS_RCODE_REFUSED); - - /* priming creates and sends a subordinate query, with - * this query as the parent. So further processing for - * this event will stop until reactivated by the - * results of priming. */ - return 0; - } - if(!iq->ratelimit_ok && qstate->prefetch_leeway) - iq->ratelimit_ok = 1; /* allow prefetches, this keeps - otherwise valid data in the cache */ - if(!iq->ratelimit_ok && infra_ratelimit_exceeded( - qstate->env->infra_cache, iq->dp->name, - iq->dp->namelen, *qstate->env->now)) { - /* and increment the rate, so that the rate for time - * now will also exceed the rate, keeping cache fresh */ - (void)infra_ratelimit_inc(qstate->env->infra_cache, - iq->dp->name, iq->dp->namelen, - *qstate->env->now); - /* see if we are passed through with slip factor */ - if(qstate->env->cfg->ratelimit_factor != 0 && - ub_random_max(qstate->env->rnd, - qstate->env->cfg->ratelimit_factor) == 1) { - iq->ratelimit_ok = 1; - log_nametypeclass(VERB_ALGO, "ratelimit allowed through for " - "delegation point", iq->dp->name, - LDNS_RR_TYPE_NS, LDNS_RR_CLASS_IN); - } else { - log_nametypeclass(VERB_ALGO, "ratelimit exceeded with " - "delegation point", iq->dp->name, - LDNS_RR_TYPE_NS, LDNS_RR_CLASS_IN); - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - } - } - - /* see if this dp not useless. - * It is useless if: - * o all NS items are required glue. - * or the query is for NS item that is required glue. - * o no addresses are provided. - * o RD qflag is on. - * Instead, go up one level, and try to get even further - * If the root was useless, use safety belt information. - * Only check cache returns, because replies for servers - * could be useless but lead to loops (bumping into the - * same server reply) if useless-checked. - */ - if(iter_dp_is_useless(&qstate->qinfo, qstate->query_flags, - iq->dp)) { - if(dname_is_root(iq->dp->name)) { - /* use safety belt */ - verbose(VERB_QUERY, "Cache has root NS but " - "no addresses. Fallback to the safety belt."); - iq->dp = hints_lookup_root(qstate->env->hints, - iq->qchase.qclass); - /* note deleg_msg is from previous lookup, - * but RD is on, so it is not used */ - if(!iq->dp) { - log_err("internal error: no hints dp"); - return error_response(qstate, id, - LDNS_RCODE_REFUSED); - } - iq->dp = delegpt_copy(iq->dp, qstate->region); - if(!iq->dp) { - log_err("out of memory in safety belt"); - return error_response(qstate, id, - LDNS_RCODE_SERVFAIL); - } - break; - } else { - verbose(VERB_ALGO, - "cache delegation was useless:"); - delegpt_log(VERB_ALGO, iq->dp); - /* go up */ - delname = iq->dp->name; - delnamelen = iq->dp->namelen; - dname_remove_label(&delname, &delnamelen); - } - } else break; - } - - verbose(VERB_ALGO, "cache delegation returns delegpt"); - delegpt_log(VERB_ALGO, iq->dp); - - /* Otherwise, set the current delegation point and move on to the - * next state. */ - return next_state(iq, INIT_REQUEST_2_STATE); -} - -/** - * Process the second part of the initial request handling. This state - * basically exists so that queries that generate root priming events have - * the same init processing as ones that do not. Request events that reach - * this state must have a valid currentDelegationPoint set. - * - * This part is primarly handling stub zone priming. Events that reach this - * state must have a current delegation point. - * - * @param qstate: query state. - * @param iq: iterator query state. - * @param id: module id. - * @return true if the event needs more request processing immediately, - * false if not. - */ -static int -processInitRequest2(struct module_qstate* qstate, struct iter_qstate* iq, - int id) -{ - uint8_t* delname; - size_t delnamelen; - log_query_info(VERB_QUERY, "resolving (init part 2): ", - &qstate->qinfo); - - if(iq->refetch_glue) { - if(!iq->dp) { - log_err("internal or malloc fail: no dp for refetch"); - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - } - delname = iq->dp->name; - delnamelen = iq->dp->namelen; - } else { - delname = iq->qchase.qname; - delnamelen = iq->qchase.qname_len; - } - if(iq->qchase.qtype == LDNS_RR_TYPE_DS || iq->refetch_glue) { - if(!dname_is_root(delname)) - dname_remove_label(&delname, &delnamelen); - iq->refetch_glue = 0; /* if CNAME causes restart, no refetch */ - } - /* Check to see if we need to prime a stub zone. */ - if(prime_stub(qstate, iq, id, delname, iq->qchase.qclass)) { - /* A priming sub request was made */ - return 0; - } - - /* most events just get forwarded to the next state. */ - return next_state(iq, INIT_REQUEST_3_STATE); -} - -/** - * Process the third part of the initial request handling. This state exists - * as a separate state so that queries that generate stub priming events - * will get the tail end of the init process but not repeat the stub priming - * check. - * - * @param qstate: query state. - * @param iq: iterator query state. - * @param id: module id. - * @return true, advancing the event to the QUERYTARGETS_STATE. - */ -static int -processInitRequest3(struct module_qstate* qstate, struct iter_qstate* iq, - int id) -{ - log_query_info(VERB_QUERY, "resolving (init part 3): ", - &qstate->qinfo); - /* if the cache reply dp equals a validation anchor or msg has DS, - * then DNSSEC RRSIGs are expected in the reply */ - iq->dnssec_expected = iter_indicates_dnssec(qstate->env, iq->dp, - iq->deleg_msg, iq->qchase.qclass); - - /* If the RD flag wasn't set, then we just finish with the - * cached referral as the response. */ - if(!(qstate->query_flags & BIT_RD) && iq->deleg_msg) { - iq->response = iq->deleg_msg; - if(verbosity >= VERB_ALGO && iq->response) - log_dns_msg("no RD requested, using delegation msg", - &iq->response->qinfo, iq->response->rep); - if(qstate->reply_origin) - sock_list_insert(&qstate->reply_origin, NULL, 0, qstate->region); - return final_state(iq); - } - /* After this point, unset the RD flag -- this query is going to - * be sent to an auth. server. */ - iq->chase_flags &= ~BIT_RD; - - /* if dnssec expected, fetch key for the trust-anchor or cached-DS */ - if(iq->dnssec_expected && qstate->env->cfg->prefetch_key && - !(qstate->query_flags&BIT_CD)) { - generate_dnskey_prefetch(qstate, iq, id); - fptr_ok(fptr_whitelist_modenv_detach_subs( - qstate->env->detach_subs)); - (*qstate->env->detach_subs)(qstate); - } - - /* Jump to the next state. */ - return next_state(iq, QUERYTARGETS_STATE); -} - -/** - * Given a basic query, generate a parent-side "target" query. - * These are subordinate queries for missing delegation point target addresses, - * for which only the parent of the delegation provides correct IP addresses. - * - * @param qstate: query state. - * @param iq: iterator query state. - * @param id: module id. - * @param name: target qname. - * @param namelen: target qname length. - * @param qtype: target qtype (either A or AAAA). - * @param qclass: target qclass. - * @return true on success, false on failure. - */ -static int -generate_parentside_target_query(struct module_qstate* qstate, - struct iter_qstate* iq, int id, uint8_t* name, size_t namelen, - uint16_t qtype, uint16_t qclass) -{ - struct module_qstate* subq; - if(!generate_sub_request(name, namelen, qtype, qclass, qstate, - id, iq, INIT_REQUEST_STATE, FINISHED_STATE, &subq, 0)) - return 0; - if(subq) { - struct iter_qstate* subiq = - (struct iter_qstate*)subq->minfo[id]; - /* blacklist the cache - we want to fetch parent stuff */ - sock_list_insert(&subq->blacklist, NULL, 0, subq->region); - subiq->query_for_pside_glue = 1; - if(dname_subdomain_c(name, iq->dp->name)) { - subiq->dp = delegpt_copy(iq->dp, subq->region); - subiq->dnssec_expected = iter_indicates_dnssec( - qstate->env, subiq->dp, NULL, - subq->qinfo.qclass); - subiq->refetch_glue = 1; - } else { - subiq->dp = dns_cache_find_delegation(qstate->env, - name, namelen, qtype, qclass, subq->region, - &subiq->deleg_msg, - *qstate->env->now+subq->prefetch_leeway); - /* if no dp, then it's from root, refetch unneeded */ - if(subiq->dp) { - subiq->dnssec_expected = iter_indicates_dnssec( - qstate->env, subiq->dp, NULL, - subq->qinfo.qclass); - subiq->refetch_glue = 1; - } - } - } - log_nametypeclass(VERB_QUERY, "new pside target", name, qtype, qclass); - return 1; -} - -/** - * Given a basic query, generate a "target" query. These are subordinate - * queries for missing delegation point target addresses. - * - * @param qstate: query state. - * @param iq: iterator query state. - * @param id: module id. - * @param name: target qname. - * @param namelen: target qname length. - * @param qtype: target qtype (either A or AAAA). - * @param qclass: target qclass. - * @return true on success, false on failure. - */ -static int -generate_target_query(struct module_qstate* qstate, struct iter_qstate* iq, - int id, uint8_t* name, size_t namelen, uint16_t qtype, uint16_t qclass) -{ - struct module_qstate* subq; - if(!generate_sub_request(name, namelen, qtype, qclass, qstate, - id, iq, INIT_REQUEST_STATE, FINISHED_STATE, &subq, 0)) - return 0; - log_nametypeclass(VERB_QUERY, "new target", name, qtype, qclass); - return 1; -} - -/** - * Given an event at a certain state, generate zero or more target queries - * for it's current delegation point. - * - * @param qstate: query state. - * @param iq: iterator query state. - * @param ie: iterator shared global environment. - * @param id: module id. - * @param maxtargets: The maximum number of targets to query for. - * if it is negative, there is no maximum number of targets. - * @param num: returns the number of queries generated and processed, - * which may be zero if there were no missing targets. - * @return false on error. - */ -static int -query_for_targets(struct module_qstate* qstate, struct iter_qstate* iq, - struct iter_env* ie, int id, int maxtargets, int* num) -{ - int query_count = 0; - struct delegpt_ns* ns; - int missing; - int toget = 0; - - if(iq->depth == ie->max_dependency_depth) - return 0; - if(iq->depth > 0 && iq->target_count && - iq->target_count[1] > MAX_TARGET_COUNT) { - char s[LDNS_MAX_DOMAINLEN+1]; - dname_str(qstate->qinfo.qname, s); - verbose(VERB_QUERY, "request %s has exceeded the maximum " - "number of glue fetches %d", s, iq->target_count[1]); - return 0; - } - - iter_mark_cycle_targets(qstate, iq->dp); - missing = (int)delegpt_count_missing_targets(iq->dp); - log_assert(maxtargets != 0); /* that would not be useful */ - - /* Generate target requests. Basically, any missing targets - * are queried for here, regardless if it is necessary to do - * so to continue processing. */ - if(maxtargets < 0 || maxtargets > missing) - toget = missing; - else toget = maxtargets; - if(toget == 0) { - *num = 0; - return 1; - } - /* select 'toget' items from the total of 'missing' items */ - log_assert(toget <= missing); - - /* loop over missing targets */ - for(ns = iq->dp->nslist; ns; ns = ns->next) { - if(ns->resolved) - continue; - - /* randomly select this item with probability toget/missing */ - if(!iter_ns_probability(qstate->env->rnd, toget, missing)) { - /* do not select this one, next; select toget number - * of items from a list one less in size */ - missing --; - continue; - } - - if(ie->supports_ipv6 && !ns->got6) { - /* Send the AAAA request. */ - if(!generate_target_query(qstate, iq, id, - ns->name, ns->namelen, - LDNS_RR_TYPE_AAAA, iq->qchase.qclass)) { - *num = query_count; - if(query_count > 0) - qstate->ext_state[id] = module_wait_subquery; - return 0; - } - query_count++; - } - /* Send the A request. */ - if(ie->supports_ipv4 && !ns->got4) { - if(!generate_target_query(qstate, iq, id, - ns->name, ns->namelen, - LDNS_RR_TYPE_A, iq->qchase.qclass)) { - *num = query_count; - if(query_count > 0) - qstate->ext_state[id] = module_wait_subquery; - return 0; - } - query_count++; - } - - /* mark this target as in progress. */ - ns->resolved = 1; - missing--; - toget--; - if(toget == 0) - break; - } - *num = query_count; - if(query_count > 0) - qstate->ext_state[id] = module_wait_subquery; - - return 1; -} - -/** see if last resort is possible - does config allow queries to parent */ -static int -can_have_last_resort(struct module_env* env, struct delegpt* dp, - struct iter_qstate* iq) -{ - struct delegpt* fwddp; - struct iter_hints_stub* stub; - /* do not process a last resort (the parent side) if a stub - * or forward is configured, because we do not want to go 'above' - * the configured servers */ - if(!dname_is_root(dp->name) && (stub = (struct iter_hints_stub*) - name_tree_find(&env->hints->tree, dp->name, dp->namelen, - dp->namelabs, iq->qchase.qclass)) && - /* has_parent side is turned off for stub_first, where we - * are allowed to go to the parent */ - stub->dp->has_parent_side_NS) { - verbose(VERB_QUERY, "configured stub servers failed -- returning SERVFAIL"); - return 0; - } - if((fwddp = forwards_find(env->fwds, dp->name, iq->qchase.qclass)) && - /* has_parent_side is turned off for forward_first, where - * we are allowed to go to the parent */ - fwddp->has_parent_side_NS) { - verbose(VERB_QUERY, "configured forward servers failed -- returning SERVFAIL"); - return 0; - } - return 1; -} - -/** - * Called by processQueryTargets when it would like extra targets to query - * but it seems to be out of options. At last resort some less appealing - * options are explored. If there are no more options, the result is SERVFAIL - * - * @param qstate: query state. - * @param iq: iterator query state. - * @param ie: iterator shared global environment. - * @param id: module id. - * @return true if the event requires more request processing immediately, - * false if not. - */ -static int -processLastResort(struct module_qstate* qstate, struct iter_qstate* iq, - struct iter_env* ie, int id) -{ - struct delegpt_ns* ns; - int query_count = 0; - verbose(VERB_ALGO, "No more query targets, attempting last resort"); - log_assert(iq->dp); - - if(!can_have_last_resort(qstate->env, iq->dp, iq)) { - /* fail -- no more targets, no more hope of targets, no hope - * of a response. */ - return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL); - } - if(!iq->dp->has_parent_side_NS && dname_is_root(iq->dp->name)) { - struct delegpt* p = hints_lookup_root(qstate->env->hints, - iq->qchase.qclass); - if(p) { - struct delegpt_ns* ns; - struct delegpt_addr* a; - iq->chase_flags &= ~BIT_RD; /* go to authorities */ - for(ns = p->nslist; ns; ns=ns->next) { - (void)delegpt_add_ns(iq->dp, qstate->region, - ns->name, ns->lame); - } - for(a = p->target_list; a; a=a->next_target) { - (void)delegpt_add_addr(iq->dp, qstate->region, - &a->addr, a->addrlen, a->bogus, - a->lame); - } - } - iq->dp->has_parent_side_NS = 1; - } else if(!iq->dp->has_parent_side_NS) { - if(!iter_lookup_parent_NS_from_cache(qstate->env, iq->dp, - qstate->region, &qstate->qinfo) - || !iq->dp->has_parent_side_NS) { - /* if: malloc failure in lookup go up to try */ - /* if: no parent NS in cache - go up one level */ - verbose(VERB_ALGO, "try to grab parent NS"); - iq->store_parent_NS = iq->dp; - iq->chase_flags &= ~BIT_RD; /* go to authorities */ - iq->deleg_msg = NULL; - iq->refetch_glue = 1; - iq->query_restart_count++; - iq->sent_count = 0; - if(qstate->env->cfg->qname_minimisation) - iq->minimisation_state = INIT_MINIMISE_STATE; - return next_state(iq, INIT_REQUEST_STATE); - } - } - /* see if that makes new names available */ - if(!cache_fill_missing(qstate->env, iq->qchase.qclass, - qstate->region, iq->dp)) - log_err("out of memory in cache_fill_missing"); - if(iq->dp->usable_list) { - verbose(VERB_ALGO, "try parent-side-name, w. glue from cache"); - return next_state(iq, QUERYTARGETS_STATE); - } - /* try to fill out parent glue from cache */ - if(iter_lookup_parent_glue_from_cache(qstate->env, iq->dp, - qstate->region, &qstate->qinfo)) { - /* got parent stuff from cache, see if we can continue */ - verbose(VERB_ALGO, "try parent-side glue from cache"); - return next_state(iq, QUERYTARGETS_STATE); - } - /* query for an extra name added by the parent-NS record */ - if(delegpt_count_missing_targets(iq->dp) > 0) { - int qs = 0; - verbose(VERB_ALGO, "try parent-side target name"); - if(!query_for_targets(qstate, iq, ie, id, 1, &qs)) { - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - } - iq->num_target_queries += qs; - target_count_increase(iq, qs); - if(qs != 0) { - qstate->ext_state[id] = module_wait_subquery; - return 0; /* and wait for them */ - } - } - if(iq->depth == ie->max_dependency_depth) { - verbose(VERB_QUERY, "maxdepth and need more nameservers, fail"); - return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL); - } - if(iq->depth > 0 && iq->target_count && - iq->target_count[1] > MAX_TARGET_COUNT) { - char s[LDNS_MAX_DOMAINLEN+1]; - dname_str(qstate->qinfo.qname, s); - verbose(VERB_QUERY, "request %s has exceeded the maximum " - "number of glue fetches %d", s, iq->target_count[1]); - return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL); - } - /* mark cycle targets for parent-side lookups */ - iter_mark_pside_cycle_targets(qstate, iq->dp); - /* see if we can issue queries to get nameserver addresses */ - /* this lookup is not randomized, but sequential. */ - for(ns = iq->dp->nslist; ns; ns = ns->next) { - /* query for parent-side A and AAAA for nameservers */ - if(ie->supports_ipv6 && !ns->done_pside6) { - /* Send the AAAA request. */ - if(!generate_parentside_target_query(qstate, iq, id, - ns->name, ns->namelen, - LDNS_RR_TYPE_AAAA, iq->qchase.qclass)) - return error_response(qstate, id, - LDNS_RCODE_SERVFAIL); - ns->done_pside6 = 1; - query_count++; - } - if(ie->supports_ipv4 && !ns->done_pside4) { - /* Send the A request. */ - if(!generate_parentside_target_query(qstate, iq, id, - ns->name, ns->namelen, - LDNS_RR_TYPE_A, iq->qchase.qclass)) - return error_response(qstate, id, - LDNS_RCODE_SERVFAIL); - ns->done_pside4 = 1; - query_count++; - } - if(query_count != 0) { /* suspend to await results */ - verbose(VERB_ALGO, "try parent-side glue lookup"); - iq->num_target_queries += query_count; - target_count_increase(iq, query_count); - qstate->ext_state[id] = module_wait_subquery; - return 0; - } - } - - /* if this was a parent-side glue query itself, then store that - * failure in cache. */ - if(!qstate->no_cache_store && iq->query_for_pside_glue - && !iq->pside_glue) - iter_store_parentside_neg(qstate->env, &qstate->qinfo, - iq->deleg_msg?iq->deleg_msg->rep: - (iq->response?iq->response->rep:NULL)); - - verbose(VERB_QUERY, "out of query targets -- returning SERVFAIL"); - /* fail -- no more targets, no more hope of targets, no hope - * of a response. */ - return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL); -} - -/** - * Try to find the NS record set that will resolve a qtype DS query. Due - * to grandparent/grandchild reasons we did not get a proper lookup right - * away. We need to create type NS queries until we get the right parent - * for this lookup. We remove labels from the query to find the right point. - * If we end up at the old dp name, then there is no solution. - * - * @param qstate: query state. - * @param iq: iterator query state. - * @param id: module id. - * @return true if the event requires more immediate processing, false if - * not. This is generally only true when forwarding the request to - * the final state (i.e., on answer). - */ -static int -processDSNSFind(struct module_qstate* qstate, struct iter_qstate* iq, int id) -{ - struct module_qstate* subq = NULL; - verbose(VERB_ALGO, "processDSNSFind"); - - if(!iq->dsns_point) { - /* initialize */ - iq->dsns_point = iq->qchase.qname; - iq->dsns_point_len = iq->qchase.qname_len; - } - /* robustcheck for internal error: we are not underneath the dp */ - if(!dname_subdomain_c(iq->dsns_point, iq->dp->name)) { - return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL); - } - - /* go up one (more) step, until we hit the dp, if so, end */ - dname_remove_label(&iq->dsns_point, &iq->dsns_point_len); - if(query_dname_compare(iq->dsns_point, iq->dp->name) == 0) { - /* there was no inbetween nameserver, use the old delegation - * point again. And this time, because dsns_point is nonNULL - * we are going to accept the (bad) result */ - iq->state = QUERYTARGETS_STATE; - return 1; - } - iq->state = DSNS_FIND_STATE; - - /* spawn NS lookup (validation not needed, this is for DS lookup) */ - log_nametypeclass(VERB_ALGO, "fetch nameservers", - iq->dsns_point, LDNS_RR_TYPE_NS, iq->qchase.qclass); - if(!generate_sub_request(iq->dsns_point, iq->dsns_point_len, - LDNS_RR_TYPE_NS, iq->qchase.qclass, qstate, id, iq, - INIT_REQUEST_STATE, FINISHED_STATE, &subq, 0)) { - return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL); - } - - return 0; -} - -/** - * This is the request event state where the request will be sent to one of - * its current query targets. This state also handles issuing target lookup - * queries for missing target IP addresses. Queries typically iterate on - * this state, both when they are just trying different targets for a given - * delegation point, and when they change delegation points. This state - * roughly corresponds to RFC 1034 algorithm steps 3 and 4. - * - * @param qstate: query state. - * @param iq: iterator query state. - * @param ie: iterator shared global environment. - * @param id: module id. - * @return true if the event requires more request processing immediately, - * false if not. This state only returns true when it is generating - * a SERVFAIL response because the query has hit a dead end. - */ -static int -processQueryTargets(struct module_qstate* qstate, struct iter_qstate* iq, - struct iter_env* ie, int id) -{ - int tf_policy; - struct delegpt_addr* target; - struct outbound_entry* outq; - - /* NOTE: a request will encounter this state for each target it - * needs to send a query to. That is, at least one per referral, - * more if some targets timeout or return throwaway answers. */ - - log_query_info(VERB_QUERY, "processQueryTargets:", &qstate->qinfo); - verbose(VERB_ALGO, "processQueryTargets: targetqueries %d, " - "currentqueries %d sentcount %d", iq->num_target_queries, - iq->num_current_queries, iq->sent_count); - - /* Make sure that we haven't run away */ - /* FIXME: is this check even necessary? */ - if(iq->referral_count > MAX_REFERRAL_COUNT) { - verbose(VERB_QUERY, "request has exceeded the maximum " - "number of referrrals with %d", iq->referral_count); - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - } - if(iq->sent_count > MAX_SENT_COUNT) { - verbose(VERB_QUERY, "request has exceeded the maximum " - "number of sends with %d", iq->sent_count); - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - } - - /* Make sure we have a delegation point, otherwise priming failed - * or another failure occurred */ - if(!iq->dp) { - verbose(VERB_QUERY, "Failed to get a delegation, giving up"); - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - } - if(!ie->supports_ipv6) - delegpt_no_ipv6(iq->dp); - if(!ie->supports_ipv4) - delegpt_no_ipv4(iq->dp); - delegpt_log(VERB_ALGO, iq->dp); - - if(iq->num_current_queries>0) { - /* already busy answering a query, this restart is because - * more delegpt addrs became available, wait for existing - * query. */ - verbose(VERB_ALGO, "woke up, but wait for outstanding query"); - qstate->ext_state[id] = module_wait_reply; - return 0; - } - - tf_policy = 0; - /* < not <=, because although the array is large enough for <=, the - * generated query will immediately be discarded due to depth and - * that servfail is cached, which is not good as opportunism goes. */ - if(iq->depth < ie->max_dependency_depth - && iq->sent_count < TARGET_FETCH_STOP) { - tf_policy = ie->target_fetch_policy[iq->depth]; - } - - /* if in 0x20 fallback get as many targets as possible */ - if(iq->caps_fallback) { - int extra = 0; - size_t naddr, nres, navail; - if(!query_for_targets(qstate, iq, ie, id, -1, &extra)) { - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - } - iq->num_target_queries += extra; - target_count_increase(iq, extra); - if(iq->num_target_queries > 0) { - /* wait to get all targets, we want to try em */ - verbose(VERB_ALGO, "wait for all targets for fallback"); - qstate->ext_state[id] = module_wait_reply; - return 0; - } - /* did we do enough fallback queries already? */ - delegpt_count_addr(iq->dp, &naddr, &nres, &navail); - /* the current caps_server is the number of fallbacks sent. - * the original query is one that matched too, so we have - * caps_server+1 number of matching queries now */ - if(iq->caps_server+1 >= naddr*3 || - iq->caps_server*2+2 >= MAX_SENT_COUNT) { - /* *2 on sentcount check because ipv6 may fail */ - /* we're done, process the response */ - verbose(VERB_ALGO, "0x20 fallback had %d responses " - "match for %d wanted, done.", - (int)iq->caps_server+1, (int)naddr*3); - iq->response = iq->caps_response; - iq->caps_fallback = 0; - iter_dec_attempts(iq->dp, 3); /* space for fallback */ - iq->num_current_queries++; /* RespState decrements it*/ - iq->referral_count++; /* make sure we don't loop */ - iq->sent_count = 0; - iq->state = QUERY_RESP_STATE; - return 1; - } - verbose(VERB_ALGO, "0x20 fallback number %d", - (int)iq->caps_server); - - /* if there is a policy to fetch missing targets - * opportunistically, do it. we rely on the fact that once a - * query (or queries) for a missing name have been issued, - * they will not show up again. */ - } else if(tf_policy != 0) { - int extra = 0; - verbose(VERB_ALGO, "attempt to get extra %d targets", - tf_policy); - (void)query_for_targets(qstate, iq, ie, id, tf_policy, &extra); - /* errors ignored, these targets are not strictly necessary for - * this result, we do not have to reply with SERVFAIL */ - iq->num_target_queries += extra; - target_count_increase(iq, extra); - } - - /* Add the current set of unused targets to our queue. */ - delegpt_add_unused_targets(iq->dp); - - /* Select the next usable target, filtering out unsuitable targets. */ - target = iter_server_selection(ie, qstate->env, iq->dp, - iq->dp->name, iq->dp->namelen, iq->qchase.qtype, - &iq->dnssec_lame_query, &iq->chase_to_rd, - iq->num_target_queries, qstate->blacklist); - - /* If no usable target was selected... */ - if(!target) { - /* Here we distinguish between three states: generate a new - * target query, just wait, or quit (with a SERVFAIL). - * We have the following information: number of active - * target queries, number of active current queries, - * the presence of missing targets at this delegation - * point, and the given query target policy. */ - - /* Check for the wait condition. If this is true, then - * an action must be taken. */ - if(iq->num_target_queries==0 && iq->num_current_queries==0) { - /* If there is nothing to wait for, then we need - * to distinguish between generating (a) new target - * query, or failing. */ - if(delegpt_count_missing_targets(iq->dp) > 0) { - int qs = 0; - verbose(VERB_ALGO, "querying for next " - "missing target"); - if(!query_for_targets(qstate, iq, ie, id, - 1, &qs)) { - return error_response(qstate, id, - LDNS_RCODE_SERVFAIL); - } - if(qs == 0 && - delegpt_count_missing_targets(iq->dp) == 0){ - /* it looked like there were missing - * targets, but they did not turn up. - * Try the bad choices again (if any), - * when we get back here missing==0, - * so this is not a loop. */ - return 1; - } - iq->num_target_queries += qs; - target_count_increase(iq, qs); - } - /* Since a target query might have been made, we - * need to check again. */ - if(iq->num_target_queries == 0) { - /* if in capsforid fallback, instead of last - * resort, we agree with the current reply - * we have (if any) (our count of addrs bad)*/ - if(iq->caps_fallback && iq->caps_reply) { - /* we're done, process the response */ - verbose(VERB_ALGO, "0x20 fallback had %d responses, " - "but no more servers except " - "last resort, done.", - (int)iq->caps_server+1); - iq->response = iq->caps_response; - iq->caps_fallback = 0; - iter_dec_attempts(iq->dp, 3); /* space for fallback */ - iq->num_current_queries++; /* RespState decrements it*/ - iq->referral_count++; /* make sure we don't loop */ - iq->sent_count = 0; - iq->state = QUERY_RESP_STATE; - return 1; - } - return processLastResort(qstate, iq, ie, id); - } - } - - /* otherwise, we have no current targets, so submerge - * until one of the target or direct queries return. */ - if(iq->num_target_queries>0 && iq->num_current_queries>0) { - verbose(VERB_ALGO, "no current targets -- waiting " - "for %d targets to resolve or %d outstanding" - " queries to respond", iq->num_target_queries, - iq->num_current_queries); - qstate->ext_state[id] = module_wait_reply; - } else if(iq->num_target_queries>0) { - verbose(VERB_ALGO, "no current targets -- waiting " - "for %d targets to resolve.", - iq->num_target_queries); - qstate->ext_state[id] = module_wait_subquery; - } else { - verbose(VERB_ALGO, "no current targets -- waiting " - "for %d outstanding queries to respond.", - iq->num_current_queries); - qstate->ext_state[id] = module_wait_reply; - } - return 0; - } - - /* if not forwarding, check ratelimits per delegationpoint name */ - if(!(iq->chase_flags & BIT_RD) && !iq->ratelimit_ok) { - if(!infra_ratelimit_inc(qstate->env->infra_cache, iq->dp->name, - iq->dp->namelen, *qstate->env->now)) { - verbose(VERB_ALGO, "query exceeded ratelimits"); - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - } - } - - if(iq->minimisation_state == INIT_MINIMISE_STATE) { - /* (Re)set qinfo_out to (new) delegation point, except when - * qinfo_out is already a subdomain of dp. This happens when - * increasing by more than one label at once (QNAMEs with more - * than MAX_MINIMISE_COUNT labels). */ - if(!(iq->qinfo_out.qname_len - && dname_subdomain_c(iq->qchase.qname, - iq->qinfo_out.qname) - && dname_subdomain_c(iq->qinfo_out.qname, - iq->dp->name))) { - iq->qinfo_out.qname = iq->dp->name; - iq->qinfo_out.qname_len = iq->dp->namelen; - iq->qinfo_out.qtype = LDNS_RR_TYPE_A; - iq->qinfo_out.qclass = iq->qchase.qclass; - iq->qinfo_out.local_alias = NULL; - iq->minimise_count = 0; - } - - iq->minimisation_state = MINIMISE_STATE; - } - if(iq->minimisation_state == MINIMISE_STATE) { - int qchaselabs = dname_count_labels(iq->qchase.qname); - int labdiff = qchaselabs - - dname_count_labels(iq->qinfo_out.qname); - - iq->qinfo_out.qname = iq->qchase.qname; - iq->qinfo_out.qname_len = iq->qchase.qname_len; - iq->minimise_count++; - iq->minimise_timeout_count = 0; - - iter_dec_attempts(iq->dp, 1); - - /* Limit number of iterations for QNAMEs with more - * than MAX_MINIMISE_COUNT labels. Send first MINIMISE_ONE_LAB - * labels of QNAME always individually. - */ - if(qchaselabs > MAX_MINIMISE_COUNT && labdiff > 1 && - iq->minimise_count > MINIMISE_ONE_LAB) { - if(iq->minimise_count < MAX_MINIMISE_COUNT) { - int multilabs = qchaselabs - 1 - - MINIMISE_ONE_LAB; - int extralabs = multilabs / - MINIMISE_MULTIPLE_LABS; - - if (MAX_MINIMISE_COUNT - iq->minimise_count >= - multilabs % MINIMISE_MULTIPLE_LABS) - /* Default behaviour is to add 1 label - * every iteration. Therefore, decrement - * the extralabs by 1 */ - extralabs--; - if (extralabs < labdiff) - labdiff -= extralabs; - else - labdiff = 1; - } - /* Last minimised iteration, send all labels with - * QTYPE=NS */ - else - labdiff = 1; - } - - if(labdiff > 1) { - verbose(VERB_QUERY, "removing %d labels", labdiff-1); - dname_remove_labels(&iq->qinfo_out.qname, - &iq->qinfo_out.qname_len, - labdiff-1); - } - if(labdiff < 1 || (labdiff < 2 - && (iq->qchase.qtype == LDNS_RR_TYPE_DS - || iq->qchase.qtype == LDNS_RR_TYPE_A))) - /* Stop minimising this query, resolve "as usual" */ - iq->minimisation_state = DONOT_MINIMISE_STATE; - else if(!qstate->no_cache_lookup) { - struct dns_msg* msg = dns_cache_lookup(qstate->env, - iq->qinfo_out.qname, iq->qinfo_out.qname_len, - iq->qinfo_out.qtype, iq->qinfo_out.qclass, - qstate->query_flags, qstate->region, - qstate->env->scratch); - if(msg && msg->rep->an_numrrsets == 0 - && FLAGS_GET_RCODE(msg->rep->flags) == - LDNS_RCODE_NOERROR) - /* no need to send query if it is already - * cached as NOERROR/NODATA */ - return 1; - } - } - if(iq->minimisation_state == SKIP_MINIMISE_STATE) { - iq->minimise_timeout_count++; - if(iq->minimise_timeout_count < MAX_MINIMISE_TIMEOUT_COUNT) - /* Do not increment qname, continue incrementing next - * iteration */ - iq->minimisation_state = MINIMISE_STATE; - else if(!qstate->env->cfg->qname_minimisation_strict) - /* Too many time-outs detected for this QNAME and QTYPE. - * We give up, disable QNAME minimisation. */ - iq->minimisation_state = DONOT_MINIMISE_STATE; - } - if(iq->minimisation_state == DONOT_MINIMISE_STATE) - iq->qinfo_out = iq->qchase; - - /* We have a valid target. */ - if(verbosity >= VERB_QUERY) { - log_query_info(VERB_QUERY, "sending query:", &iq->qinfo_out); - log_name_addr(VERB_QUERY, "sending to target:", iq->dp->name, - &target->addr, target->addrlen); - verbose(VERB_ALGO, "dnssec status: %s%s", - iq->dnssec_expected?"expected": "not expected", - iq->dnssec_lame_query?" but lame_query anyway": ""); - } - fptr_ok(fptr_whitelist_modenv_send_query(qstate->env->send_query)); - outq = (*qstate->env->send_query)(&iq->qinfo_out, - iq->chase_flags | (iq->chase_to_rd?BIT_RD:0), - /* unset CD if to forwarder(RD set) and not dnssec retry - * (blacklist nonempty) and no trust-anchors are configured - * above the qname or on the first attempt when dnssec is on */ - EDNS_DO| ((iq->chase_to_rd||(iq->chase_flags&BIT_RD)!=0)&& - !qstate->blacklist&&(!iter_indicates_dnssec_fwd(qstate->env, - &iq->qinfo_out)||target->attempts==1)?0:BIT_CD), - iq->dnssec_expected, iq->caps_fallback || is_caps_whitelisted( - ie, iq), &target->addr, target->addrlen, - iq->dp->name, iq->dp->namelen, - (iq->dp->ssl_upstream || qstate->env->cfg->ssl_upstream), qstate); - if(!outq) { - log_addr(VERB_DETAIL, "error sending query to auth server", - &target->addr, target->addrlen); - if(!(iq->chase_flags & BIT_RD) && !iq->ratelimit_ok) - infra_ratelimit_dec(qstate->env->infra_cache, iq->dp->name, - iq->dp->namelen, *qstate->env->now); - return next_state(iq, QUERYTARGETS_STATE); - } - outbound_list_insert(&iq->outlist, outq); - iq->num_current_queries++; - iq->sent_count++; - qstate->ext_state[id] = module_wait_reply; - - return 0; -} - -/** find NS rrset in given list */ -static struct ub_packed_rrset_key* -find_NS(struct reply_info* rep, size_t from, size_t to) -{ - size_t i; - for(i=from; i<to; i++) { - if(ntohs(rep->rrsets[i]->rk.type) == LDNS_RR_TYPE_NS) - return rep->rrsets[i]; - } - return NULL; -} - - -/** - * Process the query response. All queries end up at this state first. This - * process generally consists of analyzing the response and routing the - * event to the next state (either bouncing it back to a request state, or - * terminating the processing for this event). - * - * @param qstate: query state. - * @param iq: iterator query state. - * @param id: module id. - * @return true if the event requires more immediate processing, false if - * not. This is generally only true when forwarding the request to - * the final state (i.e., on answer). - */ -static int -processQueryResponse(struct module_qstate* qstate, struct iter_qstate* iq, - int id) -{ - int dnsseclame = 0; - enum response_type type; - iq->num_current_queries--; - - if(!inplace_cb_query_response_call(qstate->env, qstate, iq->response)) - log_err("unable to call query_response callback"); - - if(iq->response == NULL) { - /* Don't increment qname when QNAME minimisation is enabled */ - if(qstate->env->cfg->qname_minimisation) - iq->minimisation_state = SKIP_MINIMISE_STATE; - iq->chase_to_rd = 0; - iq->dnssec_lame_query = 0; - verbose(VERB_ALGO, "query response was timeout"); - return next_state(iq, QUERYTARGETS_STATE); - } - type = response_type_from_server( - (int)((iq->chase_flags&BIT_RD) || iq->chase_to_rd), - iq->response, &iq->qchase, iq->dp); - iq->chase_to_rd = 0; - if(type == RESPONSE_TYPE_REFERRAL && (iq->chase_flags&BIT_RD)) { - /* When forwarding (RD bit is set), we handle referrals - * differently. No queries should be sent elsewhere */ - type = RESPONSE_TYPE_ANSWER; - } - if(!qstate->env->cfg->disable_dnssec_lame_check && iq->dnssec_expected - && !iq->dnssec_lame_query && - !(iq->chase_flags&BIT_RD) - && iq->sent_count < DNSSEC_LAME_DETECT_COUNT - && type != RESPONSE_TYPE_LAME - && type != RESPONSE_TYPE_REC_LAME - && type != RESPONSE_TYPE_THROWAWAY - && type != RESPONSE_TYPE_UNTYPED) { - /* a possible answer, see if it is missing DNSSEC */ - /* but not when forwarding, so we dont mark fwder lame */ - if(!iter_msg_has_dnssec(iq->response)) { - /* Mark this address as dnsseclame in this dp, - * because that will make serverselection disprefer - * it, but also, once it is the only final option, - * use dnssec-lame-bypass if it needs to query there.*/ - if(qstate->reply) { - struct delegpt_addr* a = delegpt_find_addr( - iq->dp, &qstate->reply->addr, - qstate->reply->addrlen); - if(a) a->dnsseclame = 1; - } - /* test the answer is from the zone we expected, - * otherwise, (due to parent,child on same server), we - * might mark the server,zone lame inappropriately */ - if(!iter_msg_from_zone(iq->response, iq->dp, type, - iq->qchase.qclass)) - qstate->reply = NULL; - type = RESPONSE_TYPE_LAME; - dnsseclame = 1; - } - } else iq->dnssec_lame_query = 0; - /* see if referral brings us close to the target */ - if(type == RESPONSE_TYPE_REFERRAL) { - struct ub_packed_rrset_key* ns = find_NS( - iq->response->rep, iq->response->rep->an_numrrsets, - iq->response->rep->an_numrrsets - + iq->response->rep->ns_numrrsets); - if(!ns) ns = find_NS(iq->response->rep, 0, - iq->response->rep->an_numrrsets); - if(!ns || !dname_strict_subdomain_c(ns->rk.dname, iq->dp->name) - || !dname_subdomain_c(iq->qchase.qname, ns->rk.dname)){ - verbose(VERB_ALGO, "bad referral, throwaway"); - type = RESPONSE_TYPE_THROWAWAY; - } else - iter_scrub_ds(iq->response, ns, iq->dp->name); - } else iter_scrub_ds(iq->response, NULL, NULL); - if(type == RESPONSE_TYPE_THROWAWAY && - FLAGS_GET_RCODE(iq->response->rep->flags) == LDNS_RCODE_YXDOMAIN) { - /* YXDOMAIN is a permanent error, no need to retry */ - type = RESPONSE_TYPE_ANSWER; - } - if(type == RESPONSE_TYPE_CNAME && iq->response->rep->an_numrrsets >= 1 - && ntohs(iq->response->rep->rrsets[0]->rk.type) == LDNS_RR_TYPE_DNAME) { - uint8_t* sname = NULL; - size_t snamelen = 0; - get_cname_target(iq->response->rep->rrsets[0], &sname, - &snamelen); - if(snamelen && dname_subdomain_c(sname, iq->response->rep->rrsets[0]->rk.dname)) { - /* DNAME to a subdomain loop; do not recurse */ - type = RESPONSE_TYPE_ANSWER; - } - } - - /* handle each of the type cases */ - if(type == RESPONSE_TYPE_ANSWER) { - /* ANSWER type responses terminate the query algorithm, - * so they sent on their */ - if(verbosity >= VERB_DETAIL) { - verbose(VERB_DETAIL, "query response was %s", - FLAGS_GET_RCODE(iq->response->rep->flags) - ==LDNS_RCODE_NXDOMAIN?"NXDOMAIN ANSWER": - (iq->response->rep->an_numrrsets?"ANSWER": - "nodata ANSWER")); - } - /* if qtype is DS, check we have the right level of answer, - * like grandchild answer but we need the middle, reject it */ - if(iq->qchase.qtype == LDNS_RR_TYPE_DS && !iq->dsns_point - && !(iq->chase_flags&BIT_RD) - && iter_ds_toolow(iq->response, iq->dp) - && iter_dp_cangodown(&iq->qchase, iq->dp)) { - /* close down outstanding requests to be discarded */ - outbound_list_clear(&iq->outlist); - iq->num_current_queries = 0; - fptr_ok(fptr_whitelist_modenv_detach_subs( - qstate->env->detach_subs)); - (*qstate->env->detach_subs)(qstate); - iq->num_target_queries = 0; - return processDSNSFind(qstate, iq, id); - } - if(!qstate->no_cache_store) - iter_dns_store(qstate->env, &iq->response->qinfo, - iq->response->rep, 0, qstate->prefetch_leeway, - iq->dp&&iq->dp->has_parent_side_NS, - qstate->region, qstate->query_flags); - /* close down outstanding requests to be discarded */ - outbound_list_clear(&iq->outlist); - iq->num_current_queries = 0; - fptr_ok(fptr_whitelist_modenv_detach_subs( - qstate->env->detach_subs)); - (*qstate->env->detach_subs)(qstate); - iq->num_target_queries = 0; - if(qstate->reply) - sock_list_insert(&qstate->reply_origin, - &qstate->reply->addr, qstate->reply->addrlen, - qstate->region); - if(iq->minimisation_state != DONOT_MINIMISE_STATE) { - if(FLAGS_GET_RCODE(iq->response->rep->flags) != - LDNS_RCODE_NOERROR) { - if(qstate->env->cfg->qname_minimisation_strict) - return final_state(iq); - /* Best effort qname-minimisation. - * Stop minimising and send full query when - * RCODE is not NOERROR. */ - iq->minimisation_state = DONOT_MINIMISE_STATE; - } - if(FLAGS_GET_RCODE(iq->response->rep->flags) == - LDNS_RCODE_NXDOMAIN) { - /* Stop resolving when NXDOMAIN is DNSSEC - * signed. Based on assumption that namservers - * serving signed zones do not return NXDOMAIN - * for empty-non-terminals. */ - if(iq->dnssec_expected) - return final_state(iq); - /* Make subrequest to validate intermediate - * NXDOMAIN if harden-below-nxdomain is - * enabled. */ - if(qstate->env->cfg->harden_below_nxdomain) { - struct module_qstate* subq = NULL; - log_query_info(VERB_QUERY, - "schedule NXDOMAIN validation:", - &iq->response->qinfo); - if(!generate_sub_request( - iq->response->qinfo.qname, - iq->response->qinfo.qname_len, - iq->response->qinfo.qtype, - iq->response->qinfo.qclass, - qstate, id, iq, - INIT_REQUEST_STATE, - FINISHED_STATE, &subq, 1)) - verbose(VERB_ALGO, - "could not validate NXDOMAIN " - "response"); - } - } - return next_state(iq, QUERYTARGETS_STATE); - } - return final_state(iq); - } else if(type == RESPONSE_TYPE_REFERRAL) { - /* REFERRAL type responses get a reset of the - * delegation point, and back to the QUERYTARGETS_STATE. */ - verbose(VERB_DETAIL, "query response was REFERRAL"); - - if(!(iq->chase_flags & BIT_RD) && !iq->ratelimit_ok) { - /* we have a referral, no ratelimit, we can send - * our queries to the given name */ - infra_ratelimit_dec(qstate->env->infra_cache, - iq->dp->name, iq->dp->namelen, - *qstate->env->now); - } - - /* if hardened, only store referral if we asked for it */ - if(!qstate->no_cache_store && - (!qstate->env->cfg->harden_referral_path || - ( qstate->qinfo.qtype == LDNS_RR_TYPE_NS - && (qstate->query_flags&BIT_RD) - && !(qstate->query_flags&BIT_CD) - /* we know that all other NS rrsets are scrubbed - * away, thus on referral only one is left. - * see if that equals the query name... */ - && ( /* auth section, but sometimes in answer section*/ - reply_find_rrset_section_ns(iq->response->rep, - iq->qchase.qname, iq->qchase.qname_len, - LDNS_RR_TYPE_NS, iq->qchase.qclass) - || reply_find_rrset_section_an(iq->response->rep, - iq->qchase.qname, iq->qchase.qname_len, - LDNS_RR_TYPE_NS, iq->qchase.qclass) - ) - ))) { - /* Store the referral under the current query */ - /* no prefetch-leeway, since its not the answer */ - iter_dns_store(qstate->env, &iq->response->qinfo, - iq->response->rep, 1, 0, 0, NULL, 0); - if(iq->store_parent_NS) - iter_store_parentside_NS(qstate->env, - iq->response->rep); - if(qstate->env->neg_cache) - val_neg_addreferral(qstate->env->neg_cache, - iq->response->rep, iq->dp->name); - } - /* store parent-side-in-zone-glue, if directly queried for */ - if(!qstate->no_cache_store && iq->query_for_pside_glue - && !iq->pside_glue) { - iq->pside_glue = reply_find_rrset(iq->response->rep, - iq->qchase.qname, iq->qchase.qname_len, - iq->qchase.qtype, iq->qchase.qclass); - if(iq->pside_glue) { - log_rrset_key(VERB_ALGO, "found parent-side " - "glue", iq->pside_glue); - iter_store_parentside_rrset(qstate->env, - iq->pside_glue); - } - } - - /* Reset the event state, setting the current delegation - * point to the referral. */ - iq->deleg_msg = iq->response; - iq->dp = delegpt_from_message(iq->response, qstate->region); - if (qstate->env->cfg->qname_minimisation) - iq->minimisation_state = INIT_MINIMISE_STATE; - if(!iq->dp) - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - if(!cache_fill_missing(qstate->env, iq->qchase.qclass, - qstate->region, iq->dp)) - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - if(iq->store_parent_NS && query_dname_compare(iq->dp->name, - iq->store_parent_NS->name) == 0) - iter_merge_retry_counts(iq->dp, iq->store_parent_NS); - delegpt_log(VERB_ALGO, iq->dp); - /* Count this as a referral. */ - iq->referral_count++; - iq->sent_count = 0; - /* see if the next dp is a trust anchor, or a DS was sent - * along, indicating dnssec is expected for next zone */ - iq->dnssec_expected = iter_indicates_dnssec(qstate->env, - iq->dp, iq->response, iq->qchase.qclass); - /* if dnssec, validating then also fetch the key for the DS */ - if(iq->dnssec_expected && qstate->env->cfg->prefetch_key && - !(qstate->query_flags&BIT_CD)) - generate_dnskey_prefetch(qstate, iq, id); - - /* spawn off NS and addr to auth servers for the NS we just - * got in the referral. This gets authoritative answer - * (answer section trust level) rrset. - * right after, we detach the subs, answer goes to cache. */ - if(qstate->env->cfg->harden_referral_path) - generate_ns_check(qstate, iq, id); - - /* stop current outstanding queries. - * FIXME: should the outstanding queries be waited for and - * handled? Say by a subquery that inherits the outbound_entry. - */ - outbound_list_clear(&iq->outlist); - iq->num_current_queries = 0; - fptr_ok(fptr_whitelist_modenv_detach_subs( - qstate->env->detach_subs)); - (*qstate->env->detach_subs)(qstate); - iq->num_target_queries = 0; - verbose(VERB_ALGO, "cleared outbound list for next round"); - return next_state(iq, QUERYTARGETS_STATE); - } else if(type == RESPONSE_TYPE_CNAME) { - uint8_t* sname = NULL; - size_t snamelen = 0; - /* CNAME type responses get a query restart (i.e., get a - * reset of the query state and go back to INIT_REQUEST_STATE). - */ - verbose(VERB_DETAIL, "query response was CNAME"); - if(verbosity >= VERB_ALGO) - log_dns_msg("cname msg", &iq->response->qinfo, - iq->response->rep); - /* if qtype is DS, check we have the right level of answer, - * like grandchild answer but we need the middle, reject it */ - if(iq->qchase.qtype == LDNS_RR_TYPE_DS && !iq->dsns_point - && !(iq->chase_flags&BIT_RD) - && iter_ds_toolow(iq->response, iq->dp) - && iter_dp_cangodown(&iq->qchase, iq->dp)) { - outbound_list_clear(&iq->outlist); - iq->num_current_queries = 0; - fptr_ok(fptr_whitelist_modenv_detach_subs( - qstate->env->detach_subs)); - (*qstate->env->detach_subs)(qstate); - iq->num_target_queries = 0; - return processDSNSFind(qstate, iq, id); - } - /* Process the CNAME response. */ - if(!handle_cname_response(qstate, iq, iq->response, - &sname, &snamelen)) - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - /* cache the CNAME response under the current query */ - /* NOTE : set referral=1, so that rrsets get stored but not - * the partial query answer (CNAME only). */ - /* prefetchleeway applied because this updates answer parts */ - if(!qstate->no_cache_store) - iter_dns_store(qstate->env, &iq->response->qinfo, - iq->response->rep, 1, qstate->prefetch_leeway, - iq->dp&&iq->dp->has_parent_side_NS, NULL, - qstate->query_flags); - /* set the current request's qname to the new value. */ - iq->qchase.qname = sname; - iq->qchase.qname_len = snamelen; - if (qstate->env->cfg->qname_minimisation) - iq->minimisation_state = INIT_MINIMISE_STATE; - /* Clear the query state, since this is a query restart. */ - iq->deleg_msg = NULL; - iq->dp = NULL; - iq->dsns_point = NULL; - /* Note the query restart. */ - iq->query_restart_count++; - iq->sent_count = 0; - - /* stop current outstanding queries. - * FIXME: should the outstanding queries be waited for and - * handled? Say by a subquery that inherits the outbound_entry. - */ - outbound_list_clear(&iq->outlist); - iq->num_current_queries = 0; - fptr_ok(fptr_whitelist_modenv_detach_subs( - qstate->env->detach_subs)); - (*qstate->env->detach_subs)(qstate); - iq->num_target_queries = 0; - if(qstate->reply) - sock_list_insert(&qstate->reply_origin, - &qstate->reply->addr, qstate->reply->addrlen, - qstate->region); - verbose(VERB_ALGO, "cleared outbound list for query restart"); - /* go to INIT_REQUEST_STATE for new qname. */ - return next_state(iq, INIT_REQUEST_STATE); - } else if(type == RESPONSE_TYPE_LAME) { - /* Cache the LAMEness. */ - verbose(VERB_DETAIL, "query response was %sLAME", - dnsseclame?"DNSSEC ":""); - if(!dname_subdomain_c(iq->qchase.qname, iq->dp->name)) { - log_err("mark lame: mismatch in qname and dpname"); - /* throwaway this reply below */ - } else if(qstate->reply) { - /* need addr for lameness cache, but we may have - * gotten this from cache, so test to be sure */ - if(!infra_set_lame(qstate->env->infra_cache, - &qstate->reply->addr, qstate->reply->addrlen, - iq->dp->name, iq->dp->namelen, - *qstate->env->now, dnsseclame, 0, - iq->qchase.qtype)) - log_err("mark host lame: out of memory"); - } - } else if(type == RESPONSE_TYPE_REC_LAME) { - /* Cache the LAMEness. */ - verbose(VERB_DETAIL, "query response REC_LAME: " - "recursive but not authoritative server"); - if(!dname_subdomain_c(iq->qchase.qname, iq->dp->name)) { - log_err("mark rec_lame: mismatch in qname and dpname"); - /* throwaway this reply below */ - } else if(qstate->reply) { - /* need addr for lameness cache, but we may have - * gotten this from cache, so test to be sure */ - verbose(VERB_DETAIL, "mark as REC_LAME"); - if(!infra_set_lame(qstate->env->infra_cache, - &qstate->reply->addr, qstate->reply->addrlen, - iq->dp->name, iq->dp->namelen, - *qstate->env->now, 0, 1, iq->qchase.qtype)) - log_err("mark host lame: out of memory"); - } - } else if(type == RESPONSE_TYPE_THROWAWAY) { - /* LAME and THROWAWAY responses are handled the same way. - * In this case, the event is just sent directly back to - * the QUERYTARGETS_STATE without resetting anything, - * because, clearly, the next target must be tried. */ - verbose(VERB_DETAIL, "query response was THROWAWAY"); - } else { - log_warn("A query response came back with an unknown type: %d", - (int)type); - } - - /* LAME, THROWAWAY and "unknown" all end up here. - * Recycle to the QUERYTARGETS state to hopefully try a - * different target. */ - if (qstate->env->cfg->qname_minimisation && - !qstate->env->cfg->qname_minimisation_strict) - iq->minimisation_state = DONOT_MINIMISE_STATE; - return next_state(iq, QUERYTARGETS_STATE); -} - -/** - * Return priming query results to interested super querystates. - * - * Sets the delegation point and delegation message (not nonRD queries). - * This is a callback from walk_supers. - * - * @param qstate: priming query state that finished. - * @param id: module id. - * @param forq: the qstate for which priming has been done. - */ -static void -prime_supers(struct module_qstate* qstate, int id, struct module_qstate* forq) -{ - struct iter_qstate* foriq = (struct iter_qstate*)forq->minfo[id]; - struct delegpt* dp = NULL; - - log_assert(qstate->is_priming || foriq->wait_priming_stub); - log_assert(qstate->return_rcode == LDNS_RCODE_NOERROR); - /* Convert our response to a delegation point */ - dp = delegpt_from_message(qstate->return_msg, forq->region); - if(!dp) { - /* if there is no convertable delegation point, then - * the ANSWER type was (presumably) a negative answer. */ - verbose(VERB_ALGO, "prime response was not a positive " - "ANSWER; failing"); - foriq->dp = NULL; - foriq->state = QUERYTARGETS_STATE; - return; - } - - log_query_info(VERB_DETAIL, "priming successful for", &qstate->qinfo); - delegpt_log(VERB_ALGO, dp); - foriq->dp = dp; - foriq->deleg_msg = dns_copy_msg(qstate->return_msg, forq->region); - if(!foriq->deleg_msg) { - log_err("copy prime response: out of memory"); - foriq->dp = NULL; - foriq->state = QUERYTARGETS_STATE; - return; - } - - /* root priming responses go to init stage 2, priming stub - * responses to to stage 3. */ - if(foriq->wait_priming_stub) { - foriq->state = INIT_REQUEST_3_STATE; - foriq->wait_priming_stub = 0; - } else foriq->state = INIT_REQUEST_2_STATE; - /* because we are finished, the parent will be reactivated */ -} - -/** - * This handles the response to a priming query. This is used to handle both - * root and stub priming responses. This is basically the equivalent of the - * QUERY_RESP_STATE, but will not handle CNAME responses and will treat - * REFERRALs as ANSWERS. It will also update and reactivate the originating - * event. - * - * @param qstate: query state. - * @param id: module id. - * @return true if the event needs more immediate processing, false if not. - * This state always returns false. - */ -static int -processPrimeResponse(struct module_qstate* qstate, int id) -{ - struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id]; - enum response_type type; - iq->response->rep->flags &= ~(BIT_RD|BIT_RA); /* ignore rec-lame */ - type = response_type_from_server( - (int)((iq->chase_flags&BIT_RD) || iq->chase_to_rd), - iq->response, &iq->qchase, iq->dp); - if(type == RESPONSE_TYPE_ANSWER) { - qstate->return_rcode = LDNS_RCODE_NOERROR; - qstate->return_msg = iq->response; - } else { - qstate->return_rcode = LDNS_RCODE_SERVFAIL; - qstate->return_msg = NULL; - } - - /* validate the root or stub after priming (if enabled). - * This is the same query as the prime query, but with validation. - * Now that we are primed, the additional queries that validation - * may need can be resolved, such as DLV. */ - if(qstate->env->cfg->harden_referral_path) { - struct module_qstate* subq = NULL; - log_nametypeclass(VERB_ALGO, "schedule prime validation", - qstate->qinfo.qname, qstate->qinfo.qtype, - qstate->qinfo.qclass); - if(!generate_sub_request(qstate->qinfo.qname, - qstate->qinfo.qname_len, qstate->qinfo.qtype, - qstate->qinfo.qclass, qstate, id, iq, - INIT_REQUEST_STATE, FINISHED_STATE, &subq, 1)) { - verbose(VERB_ALGO, "could not generate prime check"); - } - generate_a_aaaa_check(qstate, iq, id); - } - - /* This event is finished. */ - qstate->ext_state[id] = module_finished; - return 0; -} - -/** - * Do final processing on responses to target queries. Events reach this - * state after the iterative resolution algorithm terminates. This state is - * responsible for reactiving the original event, and housekeeping related - * to received target responses (caching, updating the current delegation - * point, etc). - * Callback from walk_supers for every super state that is interested in - * the results from this query. - * - * @param qstate: query state. - * @param id: module id. - * @param forq: super query state. - */ -static void -processTargetResponse(struct module_qstate* qstate, int id, - struct module_qstate* forq) -{ - struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id]; - struct iter_qstate* foriq = (struct iter_qstate*)forq->minfo[id]; - struct ub_packed_rrset_key* rrset; - struct delegpt_ns* dpns; - log_assert(qstate->return_rcode == LDNS_RCODE_NOERROR); - - foriq->state = QUERYTARGETS_STATE; - log_query_info(VERB_ALGO, "processTargetResponse", &qstate->qinfo); - log_query_info(VERB_ALGO, "processTargetResponse super", &forq->qinfo); - - /* Tell the originating event that this target query has finished - * (regardless if it succeeded or not). */ - foriq->num_target_queries--; - - /* check to see if parent event is still interested (in orig name). */ - if(!foriq->dp) { - verbose(VERB_ALGO, "subq: parent not interested, was reset"); - return; /* not interested anymore */ - } - dpns = delegpt_find_ns(foriq->dp, qstate->qinfo.qname, - qstate->qinfo.qname_len); - if(!dpns) { - /* If not interested, just stop processing this event */ - verbose(VERB_ALGO, "subq: parent not interested anymore"); - /* could be because parent was jostled out of the cache, - and a new identical query arrived, that does not want it*/ - return; - } - - /* if iq->query_for_pside_glue then add the pside_glue (marked lame) */ - if(iq->pside_glue) { - /* if the pside_glue is NULL, then it could not be found, - * the done_pside is already set when created and a cache - * entry created in processFinished so nothing to do here */ - log_rrset_key(VERB_ALGO, "add parentside glue to dp", - iq->pside_glue); - if(!delegpt_add_rrset(foriq->dp, forq->region, - iq->pside_glue, 1)) - log_err("out of memory adding pside glue"); - } - - /* This response is relevant to the current query, so we - * add (attempt to add, anyway) this target(s) and reactivate - * the original event. - * NOTE: we could only look for the AnswerRRset if the - * response type was ANSWER. */ - rrset = reply_find_answer_rrset(&iq->qchase, qstate->return_msg->rep); - if(rrset) { - /* if CNAMEs have been followed - add new NS to delegpt. */ - /* BTW. RFC 1918 says NS should not have got CNAMEs. Robust. */ - if(!delegpt_find_ns(foriq->dp, rrset->rk.dname, - rrset->rk.dname_len)) { - /* if dpns->lame then set newcname ns lame too */ - if(!delegpt_add_ns(foriq->dp, forq->region, - rrset->rk.dname, dpns->lame)) - log_err("out of memory adding cnamed-ns"); - } - /* if dpns->lame then set the address(es) lame too */ - if(!delegpt_add_rrset(foriq->dp, forq->region, rrset, - dpns->lame)) - log_err("out of memory adding targets"); - verbose(VERB_ALGO, "added target response"); - delegpt_log(VERB_ALGO, foriq->dp); - } else { - verbose(VERB_ALGO, "iterator TargetResponse failed"); - dpns->resolved = 1; /* fail the target */ - } -} - -/** - * Process response for DS NS Find queries, that attempt to find the delegation - * point where we ask the DS query from. - * - * @param qstate: query state. - * @param id: module id. - * @param forq: super query state. - */ -static void -processDSNSResponse(struct module_qstate* qstate, int id, - struct module_qstate* forq) -{ - struct iter_qstate* foriq = (struct iter_qstate*)forq->minfo[id]; - - /* if the finished (iq->response) query has no NS set: continue - * up to look for the right dp; nothing to change, do DPNSstate */ - if(qstate->return_rcode != LDNS_RCODE_NOERROR) - return; /* seek further */ - /* find the NS RRset (without allowing CNAMEs) */ - if(!reply_find_rrset(qstate->return_msg->rep, qstate->qinfo.qname, - qstate->qinfo.qname_len, LDNS_RR_TYPE_NS, - qstate->qinfo.qclass)){ - return; /* seek further */ - } - - /* else, store as DP and continue at querytargets */ - foriq->state = QUERYTARGETS_STATE; - foriq->dp = delegpt_from_message(qstate->return_msg, forq->region); - if(!foriq->dp) { - log_err("out of memory in dsns dp alloc"); - return; /* dp==NULL in QUERYTARGETS makes SERVFAIL */ - } - /* success, go query the querytargets in the new dp (and go down) */ -} - -/** - * Process response for qclass=ANY queries for a particular class. - * Append to result or error-exit. - * - * @param qstate: query state. - * @param id: module id. - * @param forq: super query state. - */ -static void -processClassResponse(struct module_qstate* qstate, int id, - struct module_qstate* forq) -{ - struct iter_qstate* foriq = (struct iter_qstate*)forq->minfo[id]; - struct dns_msg* from = qstate->return_msg; - log_query_info(VERB_ALGO, "processClassResponse", &qstate->qinfo); - log_query_info(VERB_ALGO, "processClassResponse super", &forq->qinfo); - if(qstate->return_rcode != LDNS_RCODE_NOERROR) { - /* cause servfail for qclass ANY query */ - foriq->response = NULL; - foriq->state = FINISHED_STATE; - return; - } - /* append result */ - if(!foriq->response) { - /* allocate the response: copy RCODE, sec_state */ - foriq->response = dns_copy_msg(from, forq->region); - if(!foriq->response) { - log_err("malloc failed for qclass ANY response"); - foriq->state = FINISHED_STATE; - return; - } - foriq->response->qinfo.qclass = forq->qinfo.qclass; - /* qclass ANY does not receive the AA flag on replies */ - foriq->response->rep->authoritative = 0; - } else { - struct dns_msg* to = foriq->response; - /* add _from_ this response _to_ existing collection */ - /* if there are records, copy RCODE */ - /* lower sec_state if this message is lower */ - if(from->rep->rrset_count != 0) { - size_t n = from->rep->rrset_count+to->rep->rrset_count; - struct ub_packed_rrset_key** dest, **d; - /* copy appropriate rcode */ - to->rep->flags = from->rep->flags; - /* copy rrsets */ - if(from->rep->rrset_count > RR_COUNT_MAX || - to->rep->rrset_count > RR_COUNT_MAX) { - log_err("malloc failed (too many rrsets) in collect ANY"); - foriq->state = FINISHED_STATE; - return; /* integer overflow protection */ - } - dest = regional_alloc(forq->region, sizeof(dest[0])*n); - if(!dest) { - log_err("malloc failed in collect ANY"); - foriq->state = FINISHED_STATE; - return; - } - d = dest; - /* copy AN */ - memcpy(dest, to->rep->rrsets, to->rep->an_numrrsets - * sizeof(dest[0])); - dest += to->rep->an_numrrsets; - memcpy(dest, from->rep->rrsets, from->rep->an_numrrsets - * sizeof(dest[0])); - dest += from->rep->an_numrrsets; - /* copy NS */ - memcpy(dest, to->rep->rrsets+to->rep->an_numrrsets, - to->rep->ns_numrrsets * sizeof(dest[0])); - dest += to->rep->ns_numrrsets; - memcpy(dest, from->rep->rrsets+from->rep->an_numrrsets, - from->rep->ns_numrrsets * sizeof(dest[0])); - dest += from->rep->ns_numrrsets; - /* copy AR */ - memcpy(dest, to->rep->rrsets+to->rep->an_numrrsets+ - to->rep->ns_numrrsets, - to->rep->ar_numrrsets * sizeof(dest[0])); - dest += to->rep->ar_numrrsets; - memcpy(dest, from->rep->rrsets+from->rep->an_numrrsets+ - from->rep->ns_numrrsets, - from->rep->ar_numrrsets * sizeof(dest[0])); - /* update counts */ - to->rep->rrsets = d; - to->rep->an_numrrsets += from->rep->an_numrrsets; - to->rep->ns_numrrsets += from->rep->ns_numrrsets; - to->rep->ar_numrrsets += from->rep->ar_numrrsets; - to->rep->rrset_count = n; - } - if(from->rep->security < to->rep->security) /* lowest sec */ - to->rep->security = from->rep->security; - if(from->rep->qdcount != 0) /* insert qd if appropriate */ - to->rep->qdcount = from->rep->qdcount; - if(from->rep->ttl < to->rep->ttl) /* use smallest TTL */ - to->rep->ttl = from->rep->ttl; - if(from->rep->prefetch_ttl < to->rep->prefetch_ttl) - to->rep->prefetch_ttl = from->rep->prefetch_ttl; - } - /* are we done? */ - foriq->num_current_queries --; - if(foriq->num_current_queries == 0) - foriq->state = FINISHED_STATE; -} - -/** - * Collect class ANY responses and make them into one response. This - * state is started and it creates queries for all classes (that have - * root hints). The answers are then collected. - * - * @param qstate: query state. - * @param id: module id. - * @return true if the event needs more immediate processing, false if not. - */ -static int -processCollectClass(struct module_qstate* qstate, int id) -{ - struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id]; - struct module_qstate* subq; - /* If qchase.qclass == 0 then send out queries for all classes. - * Otherwise, do nothing (wait for all answers to arrive and the - * processClassResponse to put them together, and that moves us - * towards the Finished state when done. */ - if(iq->qchase.qclass == 0) { - uint16_t c = 0; - iq->qchase.qclass = LDNS_RR_CLASS_ANY; - while(iter_get_next_root(qstate->env->hints, - qstate->env->fwds, &c)) { - /* generate query for this class */ - log_nametypeclass(VERB_ALGO, "spawn collect query", - qstate->qinfo.qname, qstate->qinfo.qtype, c); - if(!generate_sub_request(qstate->qinfo.qname, - qstate->qinfo.qname_len, qstate->qinfo.qtype, - c, qstate, id, iq, INIT_REQUEST_STATE, - FINISHED_STATE, &subq, - (int)!(qstate->query_flags&BIT_CD))) { - return error_response(qstate, id, - LDNS_RCODE_SERVFAIL); - } - /* ignore subq, no special init required */ - iq->num_current_queries ++; - if(c == 0xffff) - break; - else c++; - } - /* if no roots are configured at all, return */ - if(iq->num_current_queries == 0) { - verbose(VERB_ALGO, "No root hints or fwds, giving up " - "on qclass ANY"); - return error_response(qstate, id, LDNS_RCODE_REFUSED); - } - /* return false, wait for queries to return */ - } - /* if woke up here because of an answer, wait for more answers */ - return 0; -} - -/** - * This handles the final state for first-tier responses (i.e., responses to - * externally generated queries). - * - * @param qstate: query state. - * @param iq: iterator query state. - * @param id: module id. - * @return true if the event needs more processing, false if not. Since this - * is the final state for an event, it always returns false. - */ -static int -processFinished(struct module_qstate* qstate, struct iter_qstate* iq, - int id) -{ - log_query_info(VERB_QUERY, "finishing processing for", - &qstate->qinfo); - - /* store negative cache element for parent side glue. */ - if(!qstate->no_cache_store && iq->query_for_pside_glue - && !iq->pside_glue) - iter_store_parentside_neg(qstate->env, &qstate->qinfo, - iq->deleg_msg?iq->deleg_msg->rep: - (iq->response?iq->response->rep:NULL)); - if(!iq->response) { - verbose(VERB_ALGO, "No response is set, servfail"); - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - } - - /* Make sure that the RA flag is set (since the presence of - * this module means that recursion is available) */ - iq->response->rep->flags |= BIT_RA; - - /* Clear the AA flag */ - /* FIXME: does this action go here or in some other module? */ - iq->response->rep->flags &= ~BIT_AA; - - /* make sure QR flag is on */ - iq->response->rep->flags |= BIT_QR; - - /* we have finished processing this query */ - qstate->ext_state[id] = module_finished; - - /* TODO: we are using a private TTL, trim the response. */ - /* if (mPrivateTTL > 0){IterUtils.setPrivateTTL(resp, mPrivateTTL); } */ - - /* prepend any items we have accumulated */ - if(iq->an_prepend_list || iq->ns_prepend_list) { - if(!iter_prepend(iq, iq->response, qstate->region)) { - log_err("prepend rrsets: out of memory"); - return error_response(qstate, id, LDNS_RCODE_SERVFAIL); - } - /* reset the query name back */ - iq->response->qinfo = qstate->qinfo; - /* the security state depends on the combination */ - iq->response->rep->security = sec_status_unchecked; - /* store message with the finished prepended items, - * but only if we did recursion. The nonrecursion referral - * from cache does not need to be stored in the msg cache. */ - if(!qstate->no_cache_store && qstate->query_flags&BIT_RD) { - iter_dns_store(qstate->env, &qstate->qinfo, - iq->response->rep, 0, qstate->prefetch_leeway, - iq->dp&&iq->dp->has_parent_side_NS, - qstate->region, qstate->query_flags); - } - } - qstate->return_rcode = LDNS_RCODE_NOERROR; - qstate->return_msg = iq->response; - return 0; -} - -/* - * Return priming query results to interestes super querystates. - * - * Sets the delegation point and delegation message (not nonRD queries). - * This is a callback from walk_supers. - * - * @param qstate: query state that finished. - * @param id: module id. - * @param super: the qstate to inform. - */ -void -iter_inform_super(struct module_qstate* qstate, int id, - struct module_qstate* super) -{ - if(!qstate->is_priming && super->qinfo.qclass == LDNS_RR_CLASS_ANY) - processClassResponse(qstate, id, super); - else if(super->qinfo.qtype == LDNS_RR_TYPE_DS && ((struct iter_qstate*) - super->minfo[id])->state == DSNS_FIND_STATE) - processDSNSResponse(qstate, id, super); - else if(qstate->return_rcode != LDNS_RCODE_NOERROR) - error_supers(qstate, id, super); - else if(qstate->is_priming) - prime_supers(qstate, id, super); - else processTargetResponse(qstate, id, super); -} - -/** - * Handle iterator state. - * Handle events. This is the real processing loop for events, responsible - * for moving events through the various states. If a processing method - * returns true, then it will be advanced to the next state. If false, then - * processing will stop. - * - * @param qstate: query state. - * @param ie: iterator shared global environment. - * @param iq: iterator query state. - * @param id: module id. - */ -static void -iter_handle(struct module_qstate* qstate, struct iter_qstate* iq, - struct iter_env* ie, int id) -{ - int cont = 1; - while(cont) { - verbose(VERB_ALGO, "iter_handle processing q with state %s", - iter_state_to_string(iq->state)); - switch(iq->state) { - case INIT_REQUEST_STATE: - cont = processInitRequest(qstate, iq, ie, id); - break; - case INIT_REQUEST_2_STATE: - cont = processInitRequest2(qstate, iq, id); - break; - case INIT_REQUEST_3_STATE: - cont = processInitRequest3(qstate, iq, id); - break; - case QUERYTARGETS_STATE: - cont = processQueryTargets(qstate, iq, ie, id); - break; - case QUERY_RESP_STATE: - cont = processQueryResponse(qstate, iq, id); - break; - case PRIME_RESP_STATE: - cont = processPrimeResponse(qstate, id); - break; - case COLLECT_CLASS_STATE: - cont = processCollectClass(qstate, id); - break; - case DSNS_FIND_STATE: - cont = processDSNSFind(qstate, iq, id); - break; - case FINISHED_STATE: - cont = processFinished(qstate, iq, id); - break; - default: - log_warn("iterator: invalid state: %d", - iq->state); - cont = 0; - break; - } - } -} - -/** - * This is the primary entry point for processing request events. Note that - * this method should only be used by external modules. - * @param qstate: query state. - * @param ie: iterator shared global environment. - * @param iq: iterator query state. - * @param id: module id. - */ -static void -process_request(struct module_qstate* qstate, struct iter_qstate* iq, - struct iter_env* ie, int id) -{ - /* external requests start in the INIT state, and finish using the - * FINISHED state. */ - iq->state = INIT_REQUEST_STATE; - iq->final_state = FINISHED_STATE; - verbose(VERB_ALGO, "process_request: new external request event"); - iter_handle(qstate, iq, ie, id); -} - -/** process authoritative server reply */ -static void -process_response(struct module_qstate* qstate, struct iter_qstate* iq, - struct iter_env* ie, int id, struct outbound_entry* outbound, - enum module_ev event) -{ - struct msg_parse* prs; - struct edns_data edns; - sldns_buffer* pkt; - - verbose(VERB_ALGO, "process_response: new external response event"); - iq->response = NULL; - iq->state = QUERY_RESP_STATE; - if(event == module_event_noreply || event == module_event_error) { - if(event == module_event_noreply && iq->sent_count >= 3 && - qstate->env->cfg->use_caps_bits_for_id && - !iq->caps_fallback) { - /* start fallback */ - iq->caps_fallback = 1; - iq->caps_server = 0; - iq->caps_reply = NULL; - iq->caps_response = NULL; - iq->state = QUERYTARGETS_STATE; - iq->num_current_queries--; - /* need fresh attempts for the 0x20 fallback, if - * that was the cause for the failure */ - iter_dec_attempts(iq->dp, 3); - verbose(VERB_DETAIL, "Capsforid: timeouts, starting fallback"); - goto handle_it; - } - goto handle_it; - } - if( (event != module_event_reply && event != module_event_capsfail) - || !qstate->reply) { - log_err("Bad event combined with response"); - outbound_list_remove(&iq->outlist, outbound); - (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL); - return; - } - - /* parse message */ - prs = (struct msg_parse*)regional_alloc(qstate->env->scratch, - sizeof(struct msg_parse)); - if(!prs) { - log_err("out of memory on incoming message"); - /* like packet got dropped */ - goto handle_it; - } - memset(prs, 0, sizeof(*prs)); - memset(&edns, 0, sizeof(edns)); - pkt = qstate->reply->c->buffer; - sldns_buffer_set_position(pkt, 0); - if(parse_packet(pkt, prs, qstate->env->scratch) != LDNS_RCODE_NOERROR) { - verbose(VERB_ALGO, "parse error on reply packet"); - goto handle_it; - } - /* edns is not examined, but removed from message to help cache */ - if(parse_extract_edns(prs, &edns, qstate->env->scratch) != - LDNS_RCODE_NOERROR) - goto handle_it; - - /* Copy the edns options we may got from the back end */ - if(edns.opt_list) { - qstate->edns_opts_back_in = edns_opt_copy_region(edns.opt_list, - qstate->region); - if(!qstate->edns_opts_back_in) { - log_err("out of memory on incoming message"); - /* like packet got dropped */ - goto handle_it; - } - if(!inplace_cb_edns_back_parsed_call(qstate->env, qstate)) { - log_err("unable to call edns_back_parsed callback"); - goto handle_it; - } - } - - /* remove CD-bit, we asked for in case we handle validation ourself */ - prs->flags &= ~BIT_CD; - - /* normalize and sanitize: easy to delete items from linked lists */ - if(!scrub_message(pkt, prs, &iq->qinfo_out, iq->dp->name, - qstate->env->scratch, qstate->env, ie)) { - /* if 0x20 enabled, start fallback, but we have no message */ - if(event == module_event_capsfail && !iq->caps_fallback) { - iq->caps_fallback = 1; - iq->caps_server = 0; - iq->caps_reply = NULL; - iq->caps_response = NULL; - iq->state = QUERYTARGETS_STATE; - iq->num_current_queries--; - verbose(VERB_DETAIL, "Capsforid: scrub failed, starting fallback with no response"); - } - goto handle_it; - } - - /* allocate response dns_msg in region */ - iq->response = dns_alloc_msg(pkt, prs, qstate->region); - if(!iq->response) - goto handle_it; - log_query_info(VERB_DETAIL, "response for", &qstate->qinfo); - log_name_addr(VERB_DETAIL, "reply from", iq->dp->name, - &qstate->reply->addr, qstate->reply->addrlen); - if(verbosity >= VERB_ALGO) - log_dns_msg("incoming scrubbed packet:", &iq->response->qinfo, - iq->response->rep); - - if(event == module_event_capsfail || iq->caps_fallback) { - /* for fallback we care about main answer, not additionals */ - /* removing that makes comparison more likely to succeed */ - caps_strip_reply(iq->response->rep); - if(!iq->caps_fallback) { - /* start fallback */ - iq->caps_fallback = 1; - iq->caps_server = 0; - iq->caps_reply = iq->response->rep; - iq->caps_response = iq->response; - iq->state = QUERYTARGETS_STATE; - iq->num_current_queries--; - verbose(VERB_DETAIL, "Capsforid: starting fallback"); - goto handle_it; - } else { - /* check if reply is the same, otherwise, fail */ - if(!iq->caps_reply) { - iq->caps_reply = iq->response->rep; - iq->caps_response = iq->response; - iq->caps_server = -1; /*become zero at ++, - so that we start the full set of trials */ - } else if(caps_failed_rcode(iq->caps_reply) && - !caps_failed_rcode(iq->response->rep)) { - /* prefer to upgrade to non-SERVFAIL */ - iq->caps_reply = iq->response->rep; - iq->caps_response = iq->response; - } else if(!caps_failed_rcode(iq->caps_reply) && - caps_failed_rcode(iq->response->rep)) { - /* if we have non-SERVFAIL as answer then - * we can ignore SERVFAILs for the equality - * comparison */ - /* no instructions here, skip other else */ - } else if(caps_failed_rcode(iq->caps_reply) && - caps_failed_rcode(iq->response->rep)) { - /* failure is same as other failure in fallbk*/ - /* no instructions here, skip other else */ - } else if(!reply_equal(iq->response->rep, iq->caps_reply, - qstate->env->scratch)) { - verbose(VERB_DETAIL, "Capsforid fallback: " - "getting different replies, failed"); - outbound_list_remove(&iq->outlist, outbound); - (void)error_response(qstate, id, - LDNS_RCODE_SERVFAIL); - return; - } - /* continue the fallback procedure at next server */ - iq->caps_server++; - iq->state = QUERYTARGETS_STATE; - iq->num_current_queries--; - verbose(VERB_DETAIL, "Capsforid: reply is equal. " - "go to next fallback"); - goto handle_it; - } - } - iq->caps_fallback = 0; /* if we were in fallback, 0x20 is OK now */ - -handle_it: - outbound_list_remove(&iq->outlist, outbound); - iter_handle(qstate, iq, ie, id); -} - -void -iter_operate(struct module_qstate* qstate, enum module_ev event, int id, - struct outbound_entry* outbound) -{ - struct iter_env* ie = (struct iter_env*)qstate->env->modinfo[id]; - struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id]; - verbose(VERB_QUERY, "iterator[module %d] operate: extstate:%s event:%s", - id, strextstate(qstate->ext_state[id]), strmodulevent(event)); - if(iq) log_query_info(VERB_QUERY, "iterator operate: query", - &qstate->qinfo); - if(iq && qstate->qinfo.qname != iq->qchase.qname) - log_query_info(VERB_QUERY, "iterator operate: chased to", - &iq->qchase); - - /* perform iterator state machine */ - if((event == module_event_new || event == module_event_pass) && - iq == NULL) { - if(!iter_new(qstate, id)) { - (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL); - return; - } - iq = (struct iter_qstate*)qstate->minfo[id]; - process_request(qstate, iq, ie, id); - return; - } - if(iq && event == module_event_pass) { - iter_handle(qstate, iq, ie, id); - return; - } - if(iq && outbound) { - process_response(qstate, iq, ie, id, outbound, event); - return; - } - if(event == module_event_error) { - verbose(VERB_ALGO, "got called with event error, giving up"); - (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL); - return; - } - - log_err("bad event for iterator"); - (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL); -} - -void -iter_clear(struct module_qstate* qstate, int id) -{ - struct iter_qstate* iq; - if(!qstate) - return; - iq = (struct iter_qstate*)qstate->minfo[id]; - if(iq) { - outbound_list_clear(&iq->outlist); - if(iq->target_count && --iq->target_count[0] == 0) - free(iq->target_count); - iq->num_current_queries = 0; - } - qstate->minfo[id] = NULL; -} - -size_t -iter_get_mem(struct module_env* env, int id) -{ - struct iter_env* ie = (struct iter_env*)env->modinfo[id]; - if(!ie) - return 0; - return sizeof(*ie) + sizeof(int)*((size_t)ie->max_dependency_depth+1) - + donotq_get_mem(ie->donotq) + priv_get_mem(ie->priv); -} - -/** - * The iterator function block - */ -static struct module_func_block iter_block = { - "iterator", - &iter_init, &iter_deinit, &iter_operate, &iter_inform_super, - &iter_clear, &iter_get_mem -}; - -struct module_func_block* -iter_get_funcblock(void) -{ - return &iter_block; -} - -const char* -iter_state_to_string(enum iter_state state) -{ - switch (state) - { - case INIT_REQUEST_STATE : - return "INIT REQUEST STATE"; - case INIT_REQUEST_2_STATE : - return "INIT REQUEST STATE (stage 2)"; - case INIT_REQUEST_3_STATE: - return "INIT REQUEST STATE (stage 3)"; - case QUERYTARGETS_STATE : - return "QUERY TARGETS STATE"; - case PRIME_RESP_STATE : - return "PRIME RESPONSE STATE"; - case COLLECT_CLASS_STATE : - return "COLLECT CLASS STATE"; - case DSNS_FIND_STATE : - return "DSNS FIND STATE"; - case QUERY_RESP_STATE : - return "QUERY RESPONSE STATE"; - case FINISHED_STATE : - return "FINISHED RESPONSE STATE"; - default : - return "UNKNOWN ITER STATE"; - } -} - -int -iter_state_is_responsestate(enum iter_state s) -{ - switch(s) { - case INIT_REQUEST_STATE : - case INIT_REQUEST_2_STATE : - case INIT_REQUEST_3_STATE : - case QUERYTARGETS_STATE : - case COLLECT_CLASS_STATE : - return 0; - default: - break; - } - return 1; -} |