1238106Sdes/* 2238106Sdes * iterator/iterator.c - iterative resolver DNS query response module 3238106Sdes * 4238106Sdes * Copyright (c) 2007, NLnet Labs. All rights reserved. 5238106Sdes * 6238106Sdes * This software is open source. 7238106Sdes * 8238106Sdes * Redistribution and use in source and binary forms, with or without 9238106Sdes * modification, are permitted provided that the following conditions 10238106Sdes * are met: 11238106Sdes * 12238106Sdes * Redistributions of source code must retain the above copyright notice, 13238106Sdes * this list of conditions and the following disclaimer. 14238106Sdes * 15238106Sdes * Redistributions in binary form must reproduce the above copyright notice, 16238106Sdes * this list of conditions and the following disclaimer in the documentation 17238106Sdes * and/or other materials provided with the distribution. 18238106Sdes * 19238106Sdes * Neither the name of the NLNET LABS nor the names of its contributors may 20238106Sdes * be used to endorse or promote products derived from this software without 21238106Sdes * specific prior written permission. 22238106Sdes * 23238106Sdes * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24238106Sdes * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 25238106Sdes * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 26238106Sdes * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE 27238106Sdes * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 28238106Sdes * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 29238106Sdes * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 30238106Sdes * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 31238106Sdes * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 32238106Sdes * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 33238106Sdes * POSSIBILITY OF SUCH DAMAGE. 34238106Sdes */ 35238106Sdes 36238106Sdes/** 37238106Sdes * \file 38238106Sdes * 39238106Sdes * This file contains a module that performs recusive iterative DNS query 40238106Sdes * processing. 41238106Sdes */ 42238106Sdes 43238106Sdes#include "config.h" 44238106Sdes#include <ldns/ldns.h> 45238106Sdes#include "iterator/iterator.h" 46238106Sdes#include "iterator/iter_utils.h" 47238106Sdes#include "iterator/iter_hints.h" 48238106Sdes#include "iterator/iter_fwd.h" 49238106Sdes#include "iterator/iter_donotq.h" 50238106Sdes#include "iterator/iter_delegpt.h" 51238106Sdes#include "iterator/iter_resptype.h" 52238106Sdes#include "iterator/iter_scrub.h" 53238106Sdes#include "iterator/iter_priv.h" 54238106Sdes#include "validator/val_neg.h" 55238106Sdes#include "services/cache/dns.h" 56238106Sdes#include "services/cache/infra.h" 57238106Sdes#include "util/module.h" 58238106Sdes#include "util/netevent.h" 59238106Sdes#include "util/net_help.h" 60238106Sdes#include "util/regional.h" 61238106Sdes#include "util/data/dname.h" 62238106Sdes#include "util/data/msgencode.h" 63238106Sdes#include "util/fptr_wlist.h" 64238106Sdes#include "util/config_file.h" 65238106Sdes 66238106Sdesint 67238106Sdesiter_init(struct module_env* env, int id) 68238106Sdes{ 69238106Sdes struct iter_env* iter_env = (struct iter_env*)calloc(1, 70238106Sdes sizeof(struct iter_env)); 71238106Sdes if(!iter_env) { 72238106Sdes log_err("malloc failure"); 73238106Sdes return 0; 74238106Sdes } 75238106Sdes env->modinfo[id] = (void*)iter_env; 76238106Sdes if(!iter_apply_cfg(iter_env, env->cfg)) { 77238106Sdes log_err("iterator: could not apply configuration settings."); 78238106Sdes return 0; 79238106Sdes } 80238106Sdes return 1; 81238106Sdes} 82238106Sdes 83238106Sdesvoid 84238106Sdesiter_deinit(struct module_env* env, int id) 85238106Sdes{ 86238106Sdes struct iter_env* iter_env; 87238106Sdes if(!env || !env->modinfo[id]) 88238106Sdes return; 89238106Sdes iter_env = (struct iter_env*)env->modinfo[id]; 90238106Sdes free(iter_env->target_fetch_policy); 91238106Sdes priv_delete(iter_env->priv); 92238106Sdes donotq_delete(iter_env->donotq); 93238106Sdes free(iter_env); 94238106Sdes env->modinfo[id] = NULL; 95238106Sdes} 96238106Sdes 97238106Sdes/** new query for iterator */ 98238106Sdesstatic int 99238106Sdesiter_new(struct module_qstate* qstate, int id) 100238106Sdes{ 101238106Sdes struct iter_qstate* iq = (struct iter_qstate*)regional_alloc( 102238106Sdes qstate->region, sizeof(struct iter_qstate)); 103238106Sdes qstate->minfo[id] = iq; 104238106Sdes if(!iq) 105238106Sdes return 0; 106238106Sdes memset(iq, 0, sizeof(*iq)); 107238106Sdes iq->state = INIT_REQUEST_STATE; 108238106Sdes iq->final_state = FINISHED_STATE; 109238106Sdes iq->an_prepend_list = NULL; 110238106Sdes iq->an_prepend_last = NULL; 111238106Sdes iq->ns_prepend_list = NULL; 112238106Sdes iq->ns_prepend_last = NULL; 113238106Sdes iq->dp = NULL; 114238106Sdes iq->depth = 0; 115238106Sdes iq->num_target_queries = 0; 116238106Sdes iq->num_current_queries = 0; 117238106Sdes iq->query_restart_count = 0; 118238106Sdes iq->referral_count = 0; 119238106Sdes iq->sent_count = 0; 120275854Sdelphij iq->target_count = NULL; 121238106Sdes iq->wait_priming_stub = 0; 122238106Sdes iq->refetch_glue = 0; 123238106Sdes iq->dnssec_expected = 0; 124238106Sdes iq->dnssec_lame_query = 0; 125238106Sdes iq->chase_flags = qstate->query_flags; 126238106Sdes /* Start with the (current) qname. */ 127238106Sdes iq->qchase = qstate->qinfo; 128238106Sdes outbound_list_init(&iq->outlist); 129238106Sdes return 1; 130238106Sdes} 131238106Sdes 132238106Sdes/** 133238106Sdes * Transition to the next state. This can be used to advance a currently 134238106Sdes * processing event. It cannot be used to reactivate a forEvent. 135238106Sdes * 136238106Sdes * @param iq: iterator query state 137238106Sdes * @param nextstate The state to transition to. 138238106Sdes * @return true. This is so this can be called as the return value for the 139238106Sdes * actual process*State() methods. (Transitioning to the next state 140238106Sdes * implies further processing). 141238106Sdes */ 142238106Sdesstatic int 143238106Sdesnext_state(struct iter_qstate* iq, enum iter_state nextstate) 144238106Sdes{ 145238106Sdes /* If transitioning to a "response" state, make sure that there is a 146238106Sdes * response */ 147238106Sdes if(iter_state_is_responsestate(nextstate)) { 148238106Sdes if(iq->response == NULL) { 149238106Sdes log_err("transitioning to response state sans " 150238106Sdes "response."); 151238106Sdes } 152238106Sdes } 153238106Sdes iq->state = nextstate; 154238106Sdes return 1; 155238106Sdes} 156238106Sdes 157238106Sdes/** 158238106Sdes * Transition an event to its final state. Final states always either return 159238106Sdes * a result up the module chain, or reactivate a dependent event. Which 160238106Sdes * final state to transtion to is set in the module state for the event when 161238106Sdes * it was created, and depends on the original purpose of the event. 162238106Sdes * 163238106Sdes * The response is stored in the qstate->buf buffer. 164238106Sdes * 165238106Sdes * @param iq: iterator query state 166238106Sdes * @return false. This is so this method can be used as the return value for 167238106Sdes * the processState methods. (Transitioning to the final state 168238106Sdes */ 169238106Sdesstatic int 170238106Sdesfinal_state(struct iter_qstate* iq) 171238106Sdes{ 172238106Sdes return next_state(iq, iq->final_state); 173238106Sdes} 174238106Sdes 175238106Sdes/** 176238106Sdes * Callback routine to handle errors in parent query states 177238106Sdes * @param qstate: query state that failed. 178238106Sdes * @param id: module id. 179238106Sdes * @param super: super state. 180238106Sdes */ 181238106Sdesstatic void 182238106Sdeserror_supers(struct module_qstate* qstate, int id, struct module_qstate* super) 183238106Sdes{ 184238106Sdes struct iter_qstate* super_iq = (struct iter_qstate*)super->minfo[id]; 185238106Sdes 186238106Sdes if(qstate->qinfo.qtype == LDNS_RR_TYPE_A || 187238106Sdes qstate->qinfo.qtype == LDNS_RR_TYPE_AAAA) { 188238106Sdes /* mark address as failed. */ 189238106Sdes struct delegpt_ns* dpns = NULL; 190238106Sdes if(super_iq->dp) 191238106Sdes dpns = delegpt_find_ns(super_iq->dp, 192238106Sdes qstate->qinfo.qname, qstate->qinfo.qname_len); 193238106Sdes if(!dpns) { 194238106Sdes /* not interested */ 195238106Sdes verbose(VERB_ALGO, "subq error, but not interested"); 196238106Sdes log_query_info(VERB_ALGO, "superq", &super->qinfo); 197238106Sdes if(super_iq->dp) 198238106Sdes delegpt_log(VERB_ALGO, super_iq->dp); 199238106Sdes log_assert(0); 200238106Sdes return; 201238106Sdes } else { 202238106Sdes /* see if the failure did get (parent-lame) info */ 203238106Sdes if(!cache_fill_missing(super->env, 204238106Sdes super_iq->qchase.qclass, super->region, 205238106Sdes super_iq->dp)) 206238106Sdes log_err("out of memory adding missing"); 207238106Sdes } 208238106Sdes dpns->resolved = 1; /* mark as failed */ 209238106Sdes super_iq->num_target_queries--; 210238106Sdes } 211238106Sdes if(qstate->qinfo.qtype == LDNS_RR_TYPE_NS) { 212238106Sdes /* prime failed to get delegation */ 213238106Sdes super_iq->dp = NULL; 214238106Sdes } 215238106Sdes /* evaluate targets again */ 216238106Sdes super_iq->state = QUERYTARGETS_STATE; 217238106Sdes /* super becomes runnable, and will process this change */ 218238106Sdes} 219238106Sdes 220238106Sdes/** 221238106Sdes * Return an error to the client 222238106Sdes * @param qstate: our query state 223238106Sdes * @param id: module id 224238106Sdes * @param rcode: error code (DNS errcode). 225238106Sdes * @return: 0 for use by caller, to make notation easy, like: 226238106Sdes * return error_response(..). 227238106Sdes */ 228238106Sdesstatic int 229238106Sdeserror_response(struct module_qstate* qstate, int id, int rcode) 230238106Sdes{ 231238106Sdes verbose(VERB_QUERY, "return error response %s", 232238106Sdes ldns_lookup_by_id(ldns_rcodes, rcode)? 233238106Sdes ldns_lookup_by_id(ldns_rcodes, rcode)->name:"??"); 234238106Sdes qstate->return_rcode = rcode; 235238106Sdes qstate->return_msg = NULL; 236238106Sdes qstate->ext_state[id] = module_finished; 237238106Sdes return 0; 238238106Sdes} 239238106Sdes 240238106Sdes/** 241238106Sdes * Return an error to the client and cache the error code in the 242238106Sdes * message cache (so per qname, qtype, qclass). 243238106Sdes * @param qstate: our query state 244238106Sdes * @param id: module id 245238106Sdes * @param rcode: error code (DNS errcode). 246238106Sdes * @return: 0 for use by caller, to make notation easy, like: 247238106Sdes * return error_response(..). 248238106Sdes */ 249238106Sdesstatic int 250238106Sdeserror_response_cache(struct module_qstate* qstate, int id, int rcode) 251238106Sdes{ 252238106Sdes /* store in cache */ 253238106Sdes struct reply_info err; 254238106Sdes memset(&err, 0, sizeof(err)); 255238106Sdes err.flags = (uint16_t)(BIT_QR | BIT_RA); 256238106Sdes FLAGS_SET_RCODE(err.flags, rcode); 257238106Sdes err.qdcount = 1; 258238106Sdes err.ttl = NORR_TTL; 259238106Sdes err.prefetch_ttl = PREFETCH_TTL_CALC(err.ttl); 260238106Sdes /* do not waste time trying to validate this servfail */ 261238106Sdes err.security = sec_status_indeterminate; 262238106Sdes verbose(VERB_ALGO, "store error response in message cache"); 263249141Sdes iter_dns_store(qstate->env, &qstate->qinfo, &err, 0, 0, 0, NULL); 264238106Sdes return error_response(qstate, id, rcode); 265238106Sdes} 266238106Sdes 267238106Sdes/** check if prepend item is duplicate item */ 268238106Sdesstatic int 269238106Sdesprepend_is_duplicate(struct ub_packed_rrset_key** sets, size_t to, 270238106Sdes struct ub_packed_rrset_key* dup) 271238106Sdes{ 272238106Sdes size_t i; 273238106Sdes for(i=0; i<to; i++) { 274238106Sdes if(sets[i]->rk.type == dup->rk.type && 275238106Sdes sets[i]->rk.rrset_class == dup->rk.rrset_class && 276238106Sdes sets[i]->rk.dname_len == dup->rk.dname_len && 277238106Sdes query_dname_compare(sets[i]->rk.dname, dup->rk.dname) 278238106Sdes == 0) 279238106Sdes return 1; 280238106Sdes } 281238106Sdes return 0; 282238106Sdes} 283238106Sdes 284238106Sdes/** prepend the prepend list in the answer and authority section of dns_msg */ 285238106Sdesstatic int 286238106Sdesiter_prepend(struct iter_qstate* iq, struct dns_msg* msg, 287238106Sdes struct regional* region) 288238106Sdes{ 289238106Sdes struct iter_prep_list* p; 290238106Sdes struct ub_packed_rrset_key** sets; 291238106Sdes size_t num_an = 0, num_ns = 0;; 292238106Sdes for(p = iq->an_prepend_list; p; p = p->next) 293238106Sdes num_an++; 294238106Sdes for(p = iq->ns_prepend_list; p; p = p->next) 295238106Sdes num_ns++; 296238106Sdes if(num_an + num_ns == 0) 297238106Sdes return 1; 298238106Sdes verbose(VERB_ALGO, "prepending %d rrsets", (int)num_an + (int)num_ns); 299238106Sdes sets = regional_alloc(region, (num_an+num_ns+msg->rep->rrset_count) * 300238106Sdes sizeof(struct ub_packed_rrset_key*)); 301238106Sdes if(!sets) 302238106Sdes return 0; 303238106Sdes /* ANSWER section */ 304238106Sdes num_an = 0; 305238106Sdes for(p = iq->an_prepend_list; p; p = p->next) { 306238106Sdes sets[num_an++] = p->rrset; 307238106Sdes } 308238106Sdes memcpy(sets+num_an, msg->rep->rrsets, msg->rep->an_numrrsets * 309238106Sdes sizeof(struct ub_packed_rrset_key*)); 310238106Sdes /* AUTH section */ 311238106Sdes num_ns = 0; 312238106Sdes for(p = iq->ns_prepend_list; p; p = p->next) { 313238106Sdes if(prepend_is_duplicate(sets+msg->rep->an_numrrsets+num_an, 314238106Sdes num_ns, p->rrset) || prepend_is_duplicate( 315238106Sdes msg->rep->rrsets+msg->rep->an_numrrsets, 316238106Sdes msg->rep->ns_numrrsets, p->rrset)) 317238106Sdes continue; 318238106Sdes sets[msg->rep->an_numrrsets + num_an + num_ns++] = p->rrset; 319238106Sdes } 320238106Sdes memcpy(sets + num_an + msg->rep->an_numrrsets + num_ns, 321238106Sdes msg->rep->rrsets + msg->rep->an_numrrsets, 322238106Sdes (msg->rep->ns_numrrsets + msg->rep->ar_numrrsets) * 323238106Sdes sizeof(struct ub_packed_rrset_key*)); 324238106Sdes 325238106Sdes /* NXDOMAIN rcode can stay if we prepended DNAME/CNAMEs, because 326238106Sdes * this is what recursors should give. */ 327238106Sdes msg->rep->rrset_count += num_an + num_ns; 328238106Sdes msg->rep->an_numrrsets += num_an; 329238106Sdes msg->rep->ns_numrrsets += num_ns; 330238106Sdes msg->rep->rrsets = sets; 331238106Sdes return 1; 332238106Sdes} 333238106Sdes 334238106Sdes/** 335238106Sdes * Add rrset to ANSWER prepend list 336238106Sdes * @param qstate: query state. 337238106Sdes * @param iq: iterator query state. 338238106Sdes * @param rrset: rrset to add. 339238106Sdes * @return false on failure (malloc). 340238106Sdes */ 341238106Sdesstatic int 342238106Sdesiter_add_prepend_answer(struct module_qstate* qstate, struct iter_qstate* iq, 343238106Sdes struct ub_packed_rrset_key* rrset) 344238106Sdes{ 345238106Sdes struct iter_prep_list* p = (struct iter_prep_list*)regional_alloc( 346238106Sdes qstate->region, sizeof(struct iter_prep_list)); 347238106Sdes if(!p) 348238106Sdes return 0; 349238106Sdes p->rrset = rrset; 350238106Sdes p->next = NULL; 351238106Sdes /* add at end */ 352238106Sdes if(iq->an_prepend_last) 353238106Sdes iq->an_prepend_last->next = p; 354238106Sdes else iq->an_prepend_list = p; 355238106Sdes iq->an_prepend_last = p; 356238106Sdes return 1; 357238106Sdes} 358238106Sdes 359238106Sdes/** 360238106Sdes * Add rrset to AUTHORITY prepend list 361238106Sdes * @param qstate: query state. 362238106Sdes * @param iq: iterator query state. 363238106Sdes * @param rrset: rrset to add. 364238106Sdes * @return false on failure (malloc). 365238106Sdes */ 366238106Sdesstatic int 367238106Sdesiter_add_prepend_auth(struct module_qstate* qstate, struct iter_qstate* iq, 368238106Sdes struct ub_packed_rrset_key* rrset) 369238106Sdes{ 370238106Sdes struct iter_prep_list* p = (struct iter_prep_list*)regional_alloc( 371238106Sdes qstate->region, sizeof(struct iter_prep_list)); 372238106Sdes if(!p) 373238106Sdes return 0; 374238106Sdes p->rrset = rrset; 375238106Sdes p->next = NULL; 376238106Sdes /* add at end */ 377238106Sdes if(iq->ns_prepend_last) 378238106Sdes iq->ns_prepend_last->next = p; 379238106Sdes else iq->ns_prepend_list = p; 380238106Sdes iq->ns_prepend_last = p; 381238106Sdes return 1; 382238106Sdes} 383238106Sdes 384238106Sdes/** 385238106Sdes * Given a CNAME response (defined as a response containing a CNAME or DNAME 386238106Sdes * that does not answer the request), process the response, modifying the 387238106Sdes * state as necessary. This follows the CNAME/DNAME chain and returns the 388238106Sdes * final query name. 389238106Sdes * 390238106Sdes * sets the new query name, after following the CNAME/DNAME chain. 391238106Sdes * @param qstate: query state. 392238106Sdes * @param iq: iterator query state. 393238106Sdes * @param msg: the response. 394238106Sdes * @param mname: returned target new query name. 395238106Sdes * @param mname_len: length of mname. 396238106Sdes * @return false on (malloc) error. 397238106Sdes */ 398238106Sdesstatic int 399238106Sdeshandle_cname_response(struct module_qstate* qstate, struct iter_qstate* iq, 400238106Sdes struct dns_msg* msg, uint8_t** mname, size_t* mname_len) 401238106Sdes{ 402238106Sdes size_t i; 403238106Sdes /* Start with the (current) qname. */ 404238106Sdes *mname = iq->qchase.qname; 405238106Sdes *mname_len = iq->qchase.qname_len; 406238106Sdes 407238106Sdes /* Iterate over the ANSWER rrsets in order, looking for CNAMEs and 408238106Sdes * DNAMES. */ 409238106Sdes for(i=0; i<msg->rep->an_numrrsets; i++) { 410238106Sdes struct ub_packed_rrset_key* r = msg->rep->rrsets[i]; 411238106Sdes /* If there is a (relevant) DNAME, add it to the list. 412238106Sdes * We always expect there to be CNAME that was generated 413238106Sdes * by this DNAME following, so we don't process the DNAME 414238106Sdes * directly. */ 415238106Sdes if(ntohs(r->rk.type) == LDNS_RR_TYPE_DNAME && 416238106Sdes dname_strict_subdomain_c(*mname, r->rk.dname)) { 417238106Sdes if(!iter_add_prepend_answer(qstate, iq, r)) 418238106Sdes return 0; 419238106Sdes continue; 420238106Sdes } 421238106Sdes 422238106Sdes if(ntohs(r->rk.type) == LDNS_RR_TYPE_CNAME && 423238106Sdes query_dname_compare(*mname, r->rk.dname) == 0) { 424238106Sdes /* Add this relevant CNAME rrset to the prepend list.*/ 425238106Sdes if(!iter_add_prepend_answer(qstate, iq, r)) 426238106Sdes return 0; 427238106Sdes get_cname_target(r, mname, mname_len); 428238106Sdes } 429238106Sdes 430238106Sdes /* Other rrsets in the section are ignored. */ 431238106Sdes } 432238106Sdes /* add authority rrsets to authority prepend, for wildcarded CNAMEs */ 433238106Sdes for(i=msg->rep->an_numrrsets; i<msg->rep->an_numrrsets + 434238106Sdes msg->rep->ns_numrrsets; i++) { 435238106Sdes struct ub_packed_rrset_key* r = msg->rep->rrsets[i]; 436238106Sdes /* only add NSEC/NSEC3, as they may be needed for validation */ 437238106Sdes if(ntohs(r->rk.type) == LDNS_RR_TYPE_NSEC || 438238106Sdes ntohs(r->rk.type) == LDNS_RR_TYPE_NSEC3) { 439238106Sdes if(!iter_add_prepend_auth(qstate, iq, r)) 440238106Sdes return 0; 441238106Sdes } 442238106Sdes } 443238106Sdes return 1; 444238106Sdes} 445238106Sdes 446275854Sdelphij/** create target count structure for this query */ 447275854Sdelphijstatic void 448275854Sdelphijtarget_count_create(struct iter_qstate* iq) 449275854Sdelphij{ 450275854Sdelphij if(!iq->target_count) { 451275854Sdelphij iq->target_count = (int*)calloc(2, sizeof(int)); 452275854Sdelphij /* if calloc fails we simply do not track this number */ 453275854Sdelphij if(iq->target_count) 454275854Sdelphij iq->target_count[0] = 1; 455275854Sdelphij } 456275854Sdelphij} 457275854Sdelphij 458275854Sdelphijstatic void 459275854Sdelphijtarget_count_increase(struct iter_qstate* iq, int num) 460275854Sdelphij{ 461275854Sdelphij target_count_create(iq); 462275854Sdelphij if(iq->target_count) 463275854Sdelphij iq->target_count[1] += num; 464275854Sdelphij} 465275854Sdelphij 466238106Sdes/** 467238106Sdes * Generate a subrequest. 468238106Sdes * Generate a local request event. Local events are tied to this module, and 469238106Sdes * have a correponding (first tier) event that is waiting for this event to 470238106Sdes * resolve to continue. 471238106Sdes * 472238106Sdes * @param qname The query name for this request. 473238106Sdes * @param qnamelen length of qname 474238106Sdes * @param qtype The query type for this request. 475238106Sdes * @param qclass The query class for this request. 476238106Sdes * @param qstate The event that is generating this event. 477238106Sdes * @param id: module id. 478238106Sdes * @param iq: The iterator state that is generating this event. 479238106Sdes * @param initial_state The initial response state (normally this 480238106Sdes * is QUERY_RESP_STATE, unless it is known that the request won't 481238106Sdes * need iterative processing 482238106Sdes * @param finalstate The final state for the response to this request. 483238106Sdes * @param subq_ret: if newly allocated, the subquerystate, or NULL if it does 484238106Sdes * not need initialisation. 485238106Sdes * @param v: if true, validation is done on the subquery. 486238106Sdes * @return false on error (malloc). 487238106Sdes */ 488238106Sdesstatic int 489238106Sdesgenerate_sub_request(uint8_t* qname, size_t qnamelen, uint16_t qtype, 490238106Sdes uint16_t qclass, struct module_qstate* qstate, int id, 491238106Sdes struct iter_qstate* iq, enum iter_state initial_state, 492238106Sdes enum iter_state finalstate, struct module_qstate** subq_ret, int v) 493238106Sdes{ 494238106Sdes struct module_qstate* subq = NULL; 495238106Sdes struct iter_qstate* subiq = NULL; 496238106Sdes uint16_t qflags = 0; /* OPCODE QUERY, no flags */ 497238106Sdes struct query_info qinf; 498238106Sdes int prime = (finalstate == PRIME_RESP_STATE)?1:0; 499238106Sdes qinf.qname = qname; 500238106Sdes qinf.qname_len = qnamelen; 501238106Sdes qinf.qtype = qtype; 502238106Sdes qinf.qclass = qclass; 503238106Sdes 504238106Sdes /* RD should be set only when sending the query back through the INIT 505238106Sdes * state. */ 506238106Sdes if(initial_state == INIT_REQUEST_STATE) 507238106Sdes qflags |= BIT_RD; 508238106Sdes /* We set the CD flag so we can send this through the "head" of 509238106Sdes * the resolution chain, which might have a validator. We are 510238106Sdes * uninterested in validating things not on the direct resolution 511238106Sdes * path. */ 512238106Sdes if(!v) 513238106Sdes qflags |= BIT_CD; 514238106Sdes 515238106Sdes /* attach subquery, lookup existing or make a new one */ 516238106Sdes fptr_ok(fptr_whitelist_modenv_attach_sub(qstate->env->attach_sub)); 517238106Sdes if(!(*qstate->env->attach_sub)(qstate, &qinf, qflags, prime, &subq)) { 518238106Sdes return 0; 519238106Sdes } 520238106Sdes *subq_ret = subq; 521238106Sdes if(subq) { 522238106Sdes /* initialise the new subquery */ 523238106Sdes subq->curmod = id; 524238106Sdes subq->ext_state[id] = module_state_initial; 525238106Sdes subq->minfo[id] = regional_alloc(subq->region, 526238106Sdes sizeof(struct iter_qstate)); 527238106Sdes if(!subq->minfo[id]) { 528238106Sdes log_err("init subq: out of memory"); 529238106Sdes fptr_ok(fptr_whitelist_modenv_kill_sub( 530238106Sdes qstate->env->kill_sub)); 531238106Sdes (*qstate->env->kill_sub)(subq); 532238106Sdes return 0; 533238106Sdes } 534238106Sdes subiq = (struct iter_qstate*)subq->minfo[id]; 535238106Sdes memset(subiq, 0, sizeof(*subiq)); 536238106Sdes subiq->num_target_queries = 0; 537275854Sdelphij target_count_create(iq); 538275854Sdelphij subiq->target_count = iq->target_count; 539275854Sdelphij if(iq->target_count) 540275854Sdelphij iq->target_count[0] ++; /* extra reference */ 541238106Sdes subiq->num_current_queries = 0; 542238106Sdes subiq->depth = iq->depth+1; 543238106Sdes outbound_list_init(&subiq->outlist); 544238106Sdes subiq->state = initial_state; 545238106Sdes subiq->final_state = finalstate; 546238106Sdes subiq->qchase = subq->qinfo; 547238106Sdes subiq->chase_flags = subq->query_flags; 548238106Sdes subiq->refetch_glue = 0; 549238106Sdes } 550238106Sdes return 1; 551238106Sdes} 552238106Sdes 553238106Sdes/** 554238106Sdes * Generate and send a root priming request. 555238106Sdes * @param qstate: the qtstate that triggered the need to prime. 556238106Sdes * @param iq: iterator query state. 557238106Sdes * @param id: module id. 558238106Sdes * @param qclass: the class to prime. 559238106Sdes * @return 0 on failure 560238106Sdes */ 561238106Sdesstatic int 562238106Sdesprime_root(struct module_qstate* qstate, struct iter_qstate* iq, int id, 563238106Sdes uint16_t qclass) 564238106Sdes{ 565238106Sdes struct delegpt* dp; 566238106Sdes struct module_qstate* subq; 567238106Sdes verbose(VERB_DETAIL, "priming . %s NS", 568238106Sdes ldns_lookup_by_id(ldns_rr_classes, (int)qclass)? 569238106Sdes ldns_lookup_by_id(ldns_rr_classes, (int)qclass)->name:"??"); 570238106Sdes dp = hints_lookup_root(qstate->env->hints, qclass); 571238106Sdes if(!dp) { 572238106Sdes verbose(VERB_ALGO, "Cannot prime due to lack of hints"); 573238106Sdes return 0; 574238106Sdes } 575238106Sdes /* Priming requests start at the QUERYTARGETS state, skipping 576238106Sdes * the normal INIT state logic (which would cause an infloop). */ 577238106Sdes if(!generate_sub_request((uint8_t*)"\000", 1, LDNS_RR_TYPE_NS, 578238106Sdes qclass, qstate, id, iq, QUERYTARGETS_STATE, PRIME_RESP_STATE, 579238106Sdes &subq, 0)) { 580238106Sdes verbose(VERB_ALGO, "could not prime root"); 581238106Sdes return 0; 582238106Sdes } 583238106Sdes if(subq) { 584238106Sdes struct iter_qstate* subiq = 585238106Sdes (struct iter_qstate*)subq->minfo[id]; 586238106Sdes /* Set the initial delegation point to the hint. 587238106Sdes * copy dp, it is now part of the root prime query. 588238106Sdes * dp was part of in the fixed hints structure. */ 589238106Sdes subiq->dp = delegpt_copy(dp, subq->region); 590238106Sdes if(!subiq->dp) { 591238106Sdes log_err("out of memory priming root, copydp"); 592238106Sdes fptr_ok(fptr_whitelist_modenv_kill_sub( 593238106Sdes qstate->env->kill_sub)); 594238106Sdes (*qstate->env->kill_sub)(subq); 595238106Sdes return 0; 596238106Sdes } 597238106Sdes /* there should not be any target queries. */ 598238106Sdes subiq->num_target_queries = 0; 599238106Sdes subiq->dnssec_expected = iter_indicates_dnssec( 600238106Sdes qstate->env, subiq->dp, NULL, subq->qinfo.qclass); 601238106Sdes } 602238106Sdes 603238106Sdes /* this module stops, our submodule starts, and does the query. */ 604238106Sdes qstate->ext_state[id] = module_wait_subquery; 605238106Sdes return 1; 606238106Sdes} 607238106Sdes 608238106Sdes/** 609238106Sdes * Generate and process a stub priming request. This method tests for the 610238106Sdes * need to prime a stub zone, so it is safe to call for every request. 611238106Sdes * 612238106Sdes * @param qstate: the qtstate that triggered the need to prime. 613238106Sdes * @param iq: iterator query state. 614238106Sdes * @param id: module id. 615238106Sdes * @param qname: request name. 616238106Sdes * @param qclass: request class. 617238106Sdes * @return true if a priming subrequest was made, false if not. The will only 618238106Sdes * issue a priming request if it detects an unprimed stub. 619238106Sdes * Uses value of 2 to signal during stub-prime in root-prime situation 620238106Sdes * that a noprime-stub is available and resolution can continue. 621238106Sdes */ 622238106Sdesstatic int 623238106Sdesprime_stub(struct module_qstate* qstate, struct iter_qstate* iq, int id, 624238106Sdes uint8_t* qname, uint16_t qclass) 625238106Sdes{ 626238106Sdes /* Lookup the stub hint. This will return null if the stub doesn't 627238106Sdes * need to be re-primed. */ 628238106Sdes struct iter_hints_stub* stub; 629238106Sdes struct delegpt* stub_dp; 630238106Sdes struct module_qstate* subq; 631238106Sdes 632238106Sdes if(!qname) return 0; 633238106Sdes stub = hints_lookup_stub(qstate->env->hints, qname, qclass, iq->dp); 634238106Sdes /* The stub (if there is one) does not need priming. */ 635238106Sdes if(!stub) 636238106Sdes return 0; 637238106Sdes stub_dp = stub->dp; 638238106Sdes 639238106Sdes /* is it a noprime stub (always use) */ 640238106Sdes if(stub->noprime) { 641238106Sdes int r = 0; 642238106Sdes if(iq->dp == NULL) r = 2; 643238106Sdes /* copy the dp out of the fixed hints structure, so that 644238106Sdes * it can be changed when servicing this query */ 645238106Sdes iq->dp = delegpt_copy(stub_dp, qstate->region); 646238106Sdes if(!iq->dp) { 647238106Sdes log_err("out of memory priming stub"); 648238106Sdes (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL); 649238106Sdes return 1; /* return 1 to make module stop, with error */ 650238106Sdes } 651238106Sdes log_nametypeclass(VERB_DETAIL, "use stub", stub_dp->name, 652238106Sdes LDNS_RR_TYPE_NS, qclass); 653238106Sdes return r; 654238106Sdes } 655238106Sdes 656238106Sdes /* Otherwise, we need to (re)prime the stub. */ 657238106Sdes log_nametypeclass(VERB_DETAIL, "priming stub", stub_dp->name, 658238106Sdes LDNS_RR_TYPE_NS, qclass); 659238106Sdes 660238106Sdes /* Stub priming events start at the QUERYTARGETS state to avoid the 661238106Sdes * redundant INIT state processing. */ 662238106Sdes if(!generate_sub_request(stub_dp->name, stub_dp->namelen, 663238106Sdes LDNS_RR_TYPE_NS, qclass, qstate, id, iq, 664238106Sdes QUERYTARGETS_STATE, PRIME_RESP_STATE, &subq, 0)) { 665238106Sdes verbose(VERB_ALGO, "could not prime stub"); 666238106Sdes (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL); 667238106Sdes return 1; /* return 1 to make module stop, with error */ 668238106Sdes } 669238106Sdes if(subq) { 670238106Sdes struct iter_qstate* subiq = 671238106Sdes (struct iter_qstate*)subq->minfo[id]; 672238106Sdes 673238106Sdes /* Set the initial delegation point to the hint. */ 674238106Sdes /* make copy to avoid use of stub dp by different qs/threads */ 675238106Sdes subiq->dp = delegpt_copy(stub_dp, subq->region); 676238106Sdes if(!subiq->dp) { 677238106Sdes log_err("out of memory priming stub, copydp"); 678238106Sdes fptr_ok(fptr_whitelist_modenv_kill_sub( 679238106Sdes qstate->env->kill_sub)); 680238106Sdes (*qstate->env->kill_sub)(subq); 681238106Sdes (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL); 682238106Sdes return 1; /* return 1 to make module stop, with error */ 683238106Sdes } 684238106Sdes /* there should not be any target queries -- although there 685238106Sdes * wouldn't be anyway, since stub hints never have 686238106Sdes * missing targets. */ 687238106Sdes subiq->num_target_queries = 0; 688238106Sdes subiq->wait_priming_stub = 1; 689238106Sdes subiq->dnssec_expected = iter_indicates_dnssec( 690238106Sdes qstate->env, subiq->dp, NULL, subq->qinfo.qclass); 691238106Sdes } 692238106Sdes 693238106Sdes /* this module stops, our submodule starts, and does the query. */ 694238106Sdes qstate->ext_state[id] = module_wait_subquery; 695238106Sdes return 1; 696238106Sdes} 697238106Sdes 698238106Sdes/** 699238106Sdes * Generate A and AAAA checks for glue that is in-zone for the referral 700238106Sdes * we just got to obtain authoritative information on the adresses. 701238106Sdes * 702238106Sdes * @param qstate: the qtstate that triggered the need to prime. 703238106Sdes * @param iq: iterator query state. 704238106Sdes * @param id: module id. 705238106Sdes */ 706238106Sdesstatic void 707238106Sdesgenerate_a_aaaa_check(struct module_qstate* qstate, struct iter_qstate* iq, 708238106Sdes int id) 709238106Sdes{ 710238106Sdes struct iter_env* ie = (struct iter_env*)qstate->env->modinfo[id]; 711238106Sdes struct module_qstate* subq; 712238106Sdes size_t i; 713238106Sdes struct reply_info* rep = iq->response->rep; 714238106Sdes struct ub_packed_rrset_key* s; 715238106Sdes log_assert(iq->dp); 716238106Sdes 717238106Sdes if(iq->depth == ie->max_dependency_depth) 718238106Sdes return; 719238106Sdes /* walk through additional, and check if in-zone, 720238106Sdes * only relevant A, AAAA are left after scrub anyway */ 721238106Sdes for(i=rep->an_numrrsets+rep->ns_numrrsets; i<rep->rrset_count; i++) { 722238106Sdes s = rep->rrsets[i]; 723238106Sdes /* check *ALL* addresses that are transmitted in additional*/ 724238106Sdes /* is it an address ? */ 725238106Sdes if( !(ntohs(s->rk.type)==LDNS_RR_TYPE_A || 726238106Sdes ntohs(s->rk.type)==LDNS_RR_TYPE_AAAA)) { 727238106Sdes continue; 728238106Sdes } 729238106Sdes /* is this query the same as the A/AAAA check for it */ 730238106Sdes if(qstate->qinfo.qtype == ntohs(s->rk.type) && 731238106Sdes qstate->qinfo.qclass == ntohs(s->rk.rrset_class) && 732238106Sdes query_dname_compare(qstate->qinfo.qname, 733238106Sdes s->rk.dname)==0 && 734238106Sdes (qstate->query_flags&BIT_RD) && 735238106Sdes !(qstate->query_flags&BIT_CD)) 736238106Sdes continue; 737238106Sdes 738238106Sdes /* generate subrequest for it */ 739238106Sdes log_nametypeclass(VERB_ALGO, "schedule addr fetch", 740238106Sdes s->rk.dname, ntohs(s->rk.type), 741238106Sdes ntohs(s->rk.rrset_class)); 742238106Sdes if(!generate_sub_request(s->rk.dname, s->rk.dname_len, 743238106Sdes ntohs(s->rk.type), ntohs(s->rk.rrset_class), 744238106Sdes qstate, id, iq, 745238106Sdes INIT_REQUEST_STATE, FINISHED_STATE, &subq, 1)) { 746238106Sdes verbose(VERB_ALGO, "could not generate addr check"); 747238106Sdes return; 748238106Sdes } 749238106Sdes /* ignore subq - not need for more init */ 750238106Sdes } 751238106Sdes} 752238106Sdes 753238106Sdes/** 754238106Sdes * Generate a NS check request to obtain authoritative information 755238106Sdes * on an NS rrset. 756238106Sdes * 757238106Sdes * @param qstate: the qtstate that triggered the need to prime. 758238106Sdes * @param iq: iterator query state. 759238106Sdes * @param id: module id. 760238106Sdes */ 761238106Sdesstatic void 762238106Sdesgenerate_ns_check(struct module_qstate* qstate, struct iter_qstate* iq, int id) 763238106Sdes{ 764238106Sdes struct iter_env* ie = (struct iter_env*)qstate->env->modinfo[id]; 765238106Sdes struct module_qstate* subq; 766238106Sdes log_assert(iq->dp); 767238106Sdes 768238106Sdes if(iq->depth == ie->max_dependency_depth) 769238106Sdes return; 770238106Sdes /* is this query the same as the nscheck? */ 771238106Sdes if(qstate->qinfo.qtype == LDNS_RR_TYPE_NS && 772238106Sdes query_dname_compare(iq->dp->name, qstate->qinfo.qname)==0 && 773238106Sdes (qstate->query_flags&BIT_RD) && !(qstate->query_flags&BIT_CD)){ 774238106Sdes /* spawn off A, AAAA queries for in-zone glue to check */ 775238106Sdes generate_a_aaaa_check(qstate, iq, id); 776238106Sdes return; 777238106Sdes } 778238106Sdes 779238106Sdes log_nametypeclass(VERB_ALGO, "schedule ns fetch", 780238106Sdes iq->dp->name, LDNS_RR_TYPE_NS, iq->qchase.qclass); 781238106Sdes if(!generate_sub_request(iq->dp->name, iq->dp->namelen, 782238106Sdes LDNS_RR_TYPE_NS, iq->qchase.qclass, qstate, id, iq, 783238106Sdes INIT_REQUEST_STATE, FINISHED_STATE, &subq, 1)) { 784238106Sdes verbose(VERB_ALGO, "could not generate ns check"); 785238106Sdes return; 786238106Sdes } 787238106Sdes if(subq) { 788238106Sdes struct iter_qstate* subiq = 789238106Sdes (struct iter_qstate*)subq->minfo[id]; 790238106Sdes 791238106Sdes /* make copy to avoid use of stub dp by different qs/threads */ 792238106Sdes /* refetch glue to start higher up the tree */ 793238106Sdes subiq->refetch_glue = 1; 794238106Sdes subiq->dp = delegpt_copy(iq->dp, subq->region); 795238106Sdes if(!subiq->dp) { 796238106Sdes log_err("out of memory generating ns check, copydp"); 797238106Sdes fptr_ok(fptr_whitelist_modenv_kill_sub( 798238106Sdes qstate->env->kill_sub)); 799238106Sdes (*qstate->env->kill_sub)(subq); 800238106Sdes return; 801238106Sdes } 802238106Sdes } 803238106Sdes} 804238106Sdes 805238106Sdes/** 806238106Sdes * Generate a DNSKEY prefetch query to get the DNSKEY for the DS record we 807238106Sdes * just got in a referral (where we have dnssec_expected, thus have trust 808238106Sdes * anchors above it). Note that right after calling this routine the 809238106Sdes * iterator detached subqueries (because of following the referral), and thus 810238106Sdes * the DNSKEY query becomes detached, its return stored in the cache for 811238106Sdes * later lookup by the validator. This cache lookup by the validator avoids 812238106Sdes * the roundtrip incurred by the DNSKEY query. The DNSKEY query is now 813238106Sdes * performed at about the same time the original query is sent to the domain, 814238106Sdes * thus the two answers are likely to be returned at about the same time, 815238106Sdes * saving a roundtrip from the validated lookup. 816238106Sdes * 817238106Sdes * @param qstate: the qtstate that triggered the need to prime. 818238106Sdes * @param iq: iterator query state. 819238106Sdes * @param id: module id. 820238106Sdes */ 821238106Sdesstatic void 822238106Sdesgenerate_dnskey_prefetch(struct module_qstate* qstate, 823238106Sdes struct iter_qstate* iq, int id) 824238106Sdes{ 825238106Sdes struct module_qstate* subq; 826238106Sdes log_assert(iq->dp); 827238106Sdes 828238106Sdes /* is this query the same as the prefetch? */ 829238106Sdes if(qstate->qinfo.qtype == LDNS_RR_TYPE_DNSKEY && 830238106Sdes query_dname_compare(iq->dp->name, qstate->qinfo.qname)==0 && 831238106Sdes (qstate->query_flags&BIT_RD) && !(qstate->query_flags&BIT_CD)){ 832238106Sdes return; 833238106Sdes } 834238106Sdes 835238106Sdes /* if the DNSKEY is in the cache this lookup will stop quickly */ 836238106Sdes log_nametypeclass(VERB_ALGO, "schedule dnskey prefetch", 837238106Sdes iq->dp->name, LDNS_RR_TYPE_DNSKEY, iq->qchase.qclass); 838238106Sdes if(!generate_sub_request(iq->dp->name, iq->dp->namelen, 839238106Sdes LDNS_RR_TYPE_DNSKEY, iq->qchase.qclass, qstate, id, iq, 840238106Sdes INIT_REQUEST_STATE, FINISHED_STATE, &subq, 0)) { 841238106Sdes /* we'll be slower, but it'll work */ 842238106Sdes verbose(VERB_ALGO, "could not generate dnskey prefetch"); 843238106Sdes return; 844238106Sdes } 845238106Sdes if(subq) { 846238106Sdes struct iter_qstate* subiq = 847238106Sdes (struct iter_qstate*)subq->minfo[id]; 848238106Sdes /* this qstate has the right delegation for the dnskey lookup*/ 849238106Sdes /* make copy to avoid use of stub dp by different qs/threads */ 850238106Sdes subiq->dp = delegpt_copy(iq->dp, subq->region); 851238106Sdes /* if !subiq->dp, it'll start from the cache, no problem */ 852238106Sdes } 853238106Sdes} 854238106Sdes 855238106Sdes/** 856238106Sdes * See if the query needs forwarding. 857238106Sdes * 858238106Sdes * @param qstate: query state. 859238106Sdes * @param iq: iterator query state. 860238106Sdes * @return true if the request is forwarded, false if not. 861238106Sdes * If returns true but, iq->dp is NULL then a malloc failure occurred. 862238106Sdes */ 863238106Sdesstatic int 864238106Sdesforward_request(struct module_qstate* qstate, struct iter_qstate* iq) 865238106Sdes{ 866238106Sdes struct delegpt* dp; 867238106Sdes uint8_t* delname = iq->qchase.qname; 868238106Sdes size_t delnamelen = iq->qchase.qname_len; 869238106Sdes if(iq->refetch_glue) { 870238106Sdes delname = iq->dp->name; 871238106Sdes delnamelen = iq->dp->namelen; 872238106Sdes } 873238106Sdes /* strip one label off of DS query to lookup higher for it */ 874238106Sdes if( (iq->qchase.qtype == LDNS_RR_TYPE_DS || iq->refetch_glue) 875238106Sdes && !dname_is_root(iq->qchase.qname)) 876238106Sdes dname_remove_label(&delname, &delnamelen); 877238106Sdes dp = forwards_lookup(qstate->env->fwds, delname, iq->qchase.qclass); 878238106Sdes if(!dp) 879238106Sdes return 0; 880238106Sdes /* send recursion desired to forward addr */ 881238106Sdes iq->chase_flags |= BIT_RD; 882238106Sdes iq->dp = delegpt_copy(dp, qstate->region); 883238106Sdes /* iq->dp checked by caller */ 884238106Sdes verbose(VERB_ALGO, "forwarding request"); 885238106Sdes return 1; 886238106Sdes} 887238106Sdes 888238106Sdes/** 889238106Sdes * Process the initial part of the request handling. This state roughly 890238106Sdes * corresponds to resolver algorithms steps 1 (find answer in cache) and 2 891238106Sdes * (find the best servers to ask). 892238106Sdes * 893238106Sdes * Note that all requests start here, and query restarts revisit this state. 894238106Sdes * 895238106Sdes * This state either generates: 1) a response, from cache or error, 2) a 896238106Sdes * priming event, or 3) forwards the request to the next state (init2, 897238106Sdes * generally). 898238106Sdes * 899238106Sdes * @param qstate: query state. 900238106Sdes * @param iq: iterator query state. 901238106Sdes * @param ie: iterator shared global environment. 902238106Sdes * @param id: module id. 903238106Sdes * @return true if the event needs more request processing immediately, 904238106Sdes * false if not. 905238106Sdes */ 906238106Sdesstatic int 907238106SdesprocessInitRequest(struct module_qstate* qstate, struct iter_qstate* iq, 908238106Sdes struct iter_env* ie, int id) 909238106Sdes{ 910238106Sdes uint8_t* delname; 911238106Sdes size_t delnamelen; 912238106Sdes struct dns_msg* msg; 913238106Sdes 914238106Sdes log_query_info(VERB_DETAIL, "resolving", &qstate->qinfo); 915238106Sdes /* check effort */ 916238106Sdes 917238106Sdes /* We enforce a maximum number of query restarts. This is primarily a 918238106Sdes * cheap way to prevent CNAME loops. */ 919238106Sdes if(iq->query_restart_count > MAX_RESTART_COUNT) { 920238106Sdes verbose(VERB_QUERY, "request has exceeded the maximum number" 921238106Sdes " of query restarts with %d", iq->query_restart_count); 922238106Sdes return error_response(qstate, id, LDNS_RCODE_SERVFAIL); 923238106Sdes } 924238106Sdes 925238106Sdes /* We enforce a maximum recursion/dependency depth -- in general, 926238106Sdes * this is unnecessary for dependency loops (although it will 927238106Sdes * catch those), but it provides a sensible limit to the amount 928238106Sdes * of work required to answer a given query. */ 929238106Sdes verbose(VERB_ALGO, "request has dependency depth of %d", iq->depth); 930238106Sdes if(iq->depth > ie->max_dependency_depth) { 931238106Sdes verbose(VERB_QUERY, "request has exceeded the maximum " 932238106Sdes "dependency depth with depth of %d", iq->depth); 933238106Sdes return error_response(qstate, id, LDNS_RCODE_SERVFAIL); 934238106Sdes } 935238106Sdes 936238106Sdes /* If the request is qclass=ANY, setup to generate each class */ 937238106Sdes if(qstate->qinfo.qclass == LDNS_RR_CLASS_ANY) { 938238106Sdes iq->qchase.qclass = 0; 939238106Sdes return next_state(iq, COLLECT_CLASS_STATE); 940238106Sdes } 941238106Sdes 942238106Sdes /* Resolver Algorithm Step 1 -- Look for the answer in local data. */ 943238106Sdes 944238106Sdes /* This either results in a query restart (CNAME cache response), a 945238106Sdes * terminating response (ANSWER), or a cache miss (null). */ 946238106Sdes 947238106Sdes if(qstate->blacklist) { 948238106Sdes /* if cache, or anything else, was blacklisted then 949238106Sdes * getting older results from cache is a bad idea, no cache */ 950238106Sdes verbose(VERB_ALGO, "cache blacklisted, going to the network"); 951238106Sdes msg = NULL; 952238106Sdes } else { 953238106Sdes msg = dns_cache_lookup(qstate->env, iq->qchase.qname, 954238106Sdes iq->qchase.qname_len, iq->qchase.qtype, 955238106Sdes iq->qchase.qclass, qstate->region, qstate->env->scratch); 956238106Sdes if(!msg && qstate->env->neg_cache) { 957238106Sdes /* lookup in negative cache; may result in 958238106Sdes * NOERROR/NODATA or NXDOMAIN answers that need validation */ 959238106Sdes msg = val_neg_getmsg(qstate->env->neg_cache, &iq->qchase, 960238106Sdes qstate->region, qstate->env->rrset_cache, 961238106Sdes qstate->env->scratch_buffer, 962238106Sdes *qstate->env->now, 1/*add SOA*/, NULL); 963238106Sdes } 964238106Sdes /* item taken from cache does not match our query name, thus 965238106Sdes * security needs to be re-examined later */ 966238106Sdes if(msg && query_dname_compare(qstate->qinfo.qname, 967238106Sdes iq->qchase.qname) != 0) 968238106Sdes msg->rep->security = sec_status_unchecked; 969238106Sdes } 970238106Sdes if(msg) { 971238106Sdes /* handle positive cache response */ 972238106Sdes enum response_type type = response_type_from_cache(msg, 973238106Sdes &iq->qchase); 974238106Sdes if(verbosity >= VERB_ALGO) { 975238106Sdes log_dns_msg("msg from cache lookup", &msg->qinfo, 976238106Sdes msg->rep); 977238106Sdes verbose(VERB_ALGO, "msg ttl is %d, prefetch ttl %d", 978238106Sdes (int)msg->rep->ttl, 979238106Sdes (int)msg->rep->prefetch_ttl); 980238106Sdes } 981238106Sdes 982238106Sdes if(type == RESPONSE_TYPE_CNAME) { 983238106Sdes uint8_t* sname = 0; 984238106Sdes size_t slen = 0; 985238106Sdes verbose(VERB_ALGO, "returning CNAME response from " 986238106Sdes "cache"); 987238106Sdes if(!handle_cname_response(qstate, iq, msg, 988238106Sdes &sname, &slen)) 989238106Sdes return error_response(qstate, id, 990238106Sdes LDNS_RCODE_SERVFAIL); 991238106Sdes iq->qchase.qname = sname; 992238106Sdes iq->qchase.qname_len = slen; 993238106Sdes /* This *is* a query restart, even if it is a cheap 994238106Sdes * one. */ 995238106Sdes iq->dp = NULL; 996238106Sdes iq->refetch_glue = 0; 997238106Sdes iq->query_restart_count++; 998238106Sdes iq->sent_count = 0; 999238106Sdes sock_list_insert(&qstate->reply_origin, NULL, 0, qstate->region); 1000238106Sdes return next_state(iq, INIT_REQUEST_STATE); 1001238106Sdes } 1002238106Sdes 1003238106Sdes /* if from cache, NULL, else insert 'cache IP' len=0 */ 1004238106Sdes if(qstate->reply_origin) 1005238106Sdes sock_list_insert(&qstate->reply_origin, NULL, 0, qstate->region); 1006238106Sdes /* it is an answer, response, to final state */ 1007238106Sdes verbose(VERB_ALGO, "returning answer from cache."); 1008238106Sdes iq->response = msg; 1009238106Sdes return final_state(iq); 1010238106Sdes } 1011238106Sdes 1012238106Sdes /* attempt to forward the request */ 1013238106Sdes if(forward_request(qstate, iq)) 1014238106Sdes { 1015238106Sdes if(!iq->dp) { 1016238106Sdes log_err("alloc failure for forward dp"); 1017238106Sdes return error_response(qstate, id, LDNS_RCODE_SERVFAIL); 1018238106Sdes } 1019238106Sdes iq->refetch_glue = 0; 1020238106Sdes /* the request has been forwarded. 1021238106Sdes * forwarded requests need to be immediately sent to the 1022238106Sdes * next state, QUERYTARGETS. */ 1023238106Sdes return next_state(iq, QUERYTARGETS_STATE); 1024238106Sdes } 1025238106Sdes 1026238106Sdes /* Resolver Algorithm Step 2 -- find the "best" servers. */ 1027238106Sdes 1028238106Sdes /* first, adjust for DS queries. To avoid the grandparent problem, 1029238106Sdes * we just look for the closest set of server to the parent of qname. 1030238106Sdes * When re-fetching glue we also need to ask the parent. 1031238106Sdes */ 1032238106Sdes if(iq->refetch_glue) { 1033238106Sdes if(!iq->dp) { 1034238106Sdes log_err("internal or malloc fail: no dp for refetch"); 1035238106Sdes return error_response(qstate, id, LDNS_RCODE_SERVFAIL); 1036238106Sdes } 1037238106Sdes delname = iq->dp->name; 1038238106Sdes delnamelen = iq->dp->namelen; 1039238106Sdes } else { 1040238106Sdes delname = iq->qchase.qname; 1041238106Sdes delnamelen = iq->qchase.qname_len; 1042238106Sdes } 1043238106Sdes if(iq->qchase.qtype == LDNS_RR_TYPE_DS || iq->refetch_glue || 1044238106Sdes (iq->qchase.qtype == LDNS_RR_TYPE_NS && qstate->prefetch_leeway)) { 1045238106Sdes /* remove first label from delname, root goes to hints, 1046238106Sdes * but only to fetch glue, not for qtype=DS. */ 1047238106Sdes /* also when prefetching an NS record, fetch it again from 1048238106Sdes * its parent, just as if it expired, so that you do not 1049238106Sdes * get stuck on an older nameserver that gives old NSrecords */ 1050238106Sdes if(dname_is_root(delname) && (iq->refetch_glue || 1051238106Sdes (iq->qchase.qtype == LDNS_RR_TYPE_NS && 1052238106Sdes qstate->prefetch_leeway))) 1053238106Sdes delname = NULL; /* go to root priming */ 1054238106Sdes else dname_remove_label(&delname, &delnamelen); 1055238106Sdes } 1056238106Sdes /* delname is the name to lookup a delegation for. If NULL rootprime */ 1057238106Sdes while(1) { 1058238106Sdes 1059238106Sdes /* Lookup the delegation in the cache. If null, then the 1060238106Sdes * cache needs to be primed for the qclass. */ 1061238106Sdes if(delname) 1062238106Sdes iq->dp = dns_cache_find_delegation(qstate->env, delname, 1063238106Sdes delnamelen, iq->qchase.qtype, iq->qchase.qclass, 1064238106Sdes qstate->region, &iq->deleg_msg, 1065238106Sdes *qstate->env->now+qstate->prefetch_leeway); 1066238106Sdes else iq->dp = NULL; 1067238106Sdes 1068238106Sdes /* If the cache has returned nothing, then we have a 1069238106Sdes * root priming situation. */ 1070238106Sdes if(iq->dp == NULL) { 1071238106Sdes /* if there is a stub, then no root prime needed */ 1072238106Sdes int r = prime_stub(qstate, iq, id, delname, 1073238106Sdes iq->qchase.qclass); 1074238106Sdes if(r == 2) 1075238106Sdes break; /* got noprime-stub-zone, continue */ 1076238106Sdes else if(r) 1077238106Sdes return 0; /* stub prime request made */ 1078238106Sdes if(forwards_lookup_root(qstate->env->fwds, 1079238106Sdes iq->qchase.qclass)) { 1080238106Sdes /* forward zone root, no root prime needed */ 1081238106Sdes /* fill in some dp - safety belt */ 1082238106Sdes iq->dp = hints_lookup_root(qstate->env->hints, 1083238106Sdes iq->qchase.qclass); 1084238106Sdes if(!iq->dp) { 1085238106Sdes log_err("internal error: no hints dp"); 1086238106Sdes return error_response(qstate, id, 1087238106Sdes LDNS_RCODE_SERVFAIL); 1088238106Sdes } 1089238106Sdes iq->dp = delegpt_copy(iq->dp, qstate->region); 1090238106Sdes if(!iq->dp) { 1091238106Sdes log_err("out of memory in safety belt"); 1092238106Sdes return error_response(qstate, id, 1093238106Sdes LDNS_RCODE_SERVFAIL); 1094238106Sdes } 1095238106Sdes return next_state(iq, INIT_REQUEST_2_STATE); 1096238106Sdes } 1097238106Sdes /* Note that the result of this will set a new 1098238106Sdes * DelegationPoint based on the result of priming. */ 1099238106Sdes if(!prime_root(qstate, iq, id, iq->qchase.qclass)) 1100238106Sdes return error_response(qstate, id, 1101238106Sdes LDNS_RCODE_REFUSED); 1102238106Sdes 1103238106Sdes /* priming creates and sends a subordinate query, with 1104238106Sdes * this query as the parent. So further processing for 1105238106Sdes * this event will stop until reactivated by the 1106238106Sdes * results of priming. */ 1107238106Sdes return 0; 1108238106Sdes } 1109238106Sdes 1110238106Sdes /* see if this dp not useless. 1111238106Sdes * It is useless if: 1112238106Sdes * o all NS items are required glue. 1113238106Sdes * or the query is for NS item that is required glue. 1114238106Sdes * o no addresses are provided. 1115238106Sdes * o RD qflag is on. 1116238106Sdes * Instead, go up one level, and try to get even further 1117238106Sdes * If the root was useless, use safety belt information. 1118238106Sdes * Only check cache returns, because replies for servers 1119238106Sdes * could be useless but lead to loops (bumping into the 1120238106Sdes * same server reply) if useless-checked. 1121238106Sdes */ 1122238106Sdes if(iter_dp_is_useless(&qstate->qinfo, qstate->query_flags, 1123238106Sdes iq->dp)) { 1124238106Sdes if(dname_is_root(iq->dp->name)) { 1125238106Sdes /* use safety belt */ 1126238106Sdes verbose(VERB_QUERY, "Cache has root NS but " 1127238106Sdes "no addresses. Fallback to the safety belt."); 1128238106Sdes iq->dp = hints_lookup_root(qstate->env->hints, 1129238106Sdes iq->qchase.qclass); 1130238106Sdes /* note deleg_msg is from previous lookup, 1131238106Sdes * but RD is on, so it is not used */ 1132238106Sdes if(!iq->dp) { 1133238106Sdes log_err("internal error: no hints dp"); 1134238106Sdes return error_response(qstate, id, 1135238106Sdes LDNS_RCODE_REFUSED); 1136238106Sdes } 1137238106Sdes iq->dp = delegpt_copy(iq->dp, qstate->region); 1138238106Sdes if(!iq->dp) { 1139238106Sdes log_err("out of memory in safety belt"); 1140238106Sdes return error_response(qstate, id, 1141238106Sdes LDNS_RCODE_SERVFAIL); 1142238106Sdes } 1143238106Sdes break; 1144238106Sdes } else { 1145238106Sdes verbose(VERB_ALGO, 1146238106Sdes "cache delegation was useless:"); 1147238106Sdes delegpt_log(VERB_ALGO, iq->dp); 1148238106Sdes /* go up */ 1149238106Sdes delname = iq->dp->name; 1150238106Sdes delnamelen = iq->dp->namelen; 1151238106Sdes dname_remove_label(&delname, &delnamelen); 1152238106Sdes } 1153238106Sdes } else break; 1154238106Sdes } 1155238106Sdes 1156238106Sdes verbose(VERB_ALGO, "cache delegation returns delegpt"); 1157238106Sdes delegpt_log(VERB_ALGO, iq->dp); 1158238106Sdes 1159238106Sdes /* Otherwise, set the current delegation point and move on to the 1160238106Sdes * next state. */ 1161238106Sdes return next_state(iq, INIT_REQUEST_2_STATE); 1162238106Sdes} 1163238106Sdes 1164238106Sdes/** 1165238106Sdes * Process the second part of the initial request handling. This state 1166238106Sdes * basically exists so that queries that generate root priming events have 1167238106Sdes * the same init processing as ones that do not. Request events that reach 1168238106Sdes * this state must have a valid currentDelegationPoint set. 1169238106Sdes * 1170238106Sdes * This part is primarly handling stub zone priming. Events that reach this 1171238106Sdes * state must have a current delegation point. 1172238106Sdes * 1173238106Sdes * @param qstate: query state. 1174238106Sdes * @param iq: iterator query state. 1175238106Sdes * @param id: module id. 1176238106Sdes * @return true if the event needs more request processing immediately, 1177238106Sdes * false if not. 1178238106Sdes */ 1179238106Sdesstatic int 1180238106SdesprocessInitRequest2(struct module_qstate* qstate, struct iter_qstate* iq, 1181238106Sdes int id) 1182238106Sdes{ 1183238106Sdes uint8_t* delname; 1184238106Sdes size_t delnamelen; 1185238106Sdes log_query_info(VERB_QUERY, "resolving (init part 2): ", 1186238106Sdes &qstate->qinfo); 1187238106Sdes 1188238106Sdes if(iq->refetch_glue) { 1189238106Sdes if(!iq->dp) { 1190238106Sdes log_err("internal or malloc fail: no dp for refetch"); 1191238106Sdes return error_response(qstate, id, LDNS_RCODE_SERVFAIL); 1192238106Sdes } 1193238106Sdes delname = iq->dp->name; 1194238106Sdes delnamelen = iq->dp->namelen; 1195238106Sdes } else { 1196238106Sdes delname = iq->qchase.qname; 1197238106Sdes delnamelen = iq->qchase.qname_len; 1198238106Sdes } 1199238106Sdes if(iq->qchase.qtype == LDNS_RR_TYPE_DS || iq->refetch_glue) { 1200238106Sdes if(!dname_is_root(delname)) 1201238106Sdes dname_remove_label(&delname, &delnamelen); 1202238106Sdes iq->refetch_glue = 0; /* if CNAME causes restart, no refetch */ 1203238106Sdes } 1204238106Sdes /* Check to see if we need to prime a stub zone. */ 1205238106Sdes if(prime_stub(qstate, iq, id, delname, iq->qchase.qclass)) { 1206238106Sdes /* A priming sub request was made */ 1207238106Sdes return 0; 1208238106Sdes } 1209238106Sdes 1210238106Sdes /* most events just get forwarded to the next state. */ 1211238106Sdes return next_state(iq, INIT_REQUEST_3_STATE); 1212238106Sdes} 1213238106Sdes 1214238106Sdes/** 1215238106Sdes * Process the third part of the initial request handling. This state exists 1216238106Sdes * as a separate state so that queries that generate stub priming events 1217238106Sdes * will get the tail end of the init process but not repeat the stub priming 1218238106Sdes * check. 1219238106Sdes * 1220238106Sdes * @param qstate: query state. 1221238106Sdes * @param iq: iterator query state. 1222238106Sdes * @param id: module id. 1223238106Sdes * @return true, advancing the event to the QUERYTARGETS_STATE. 1224238106Sdes */ 1225238106Sdesstatic int 1226238106SdesprocessInitRequest3(struct module_qstate* qstate, struct iter_qstate* iq, 1227238106Sdes int id) 1228238106Sdes{ 1229238106Sdes log_query_info(VERB_QUERY, "resolving (init part 3): ", 1230238106Sdes &qstate->qinfo); 1231238106Sdes /* if the cache reply dp equals a validation anchor or msg has DS, 1232238106Sdes * then DNSSEC RRSIGs are expected in the reply */ 1233238106Sdes iq->dnssec_expected = iter_indicates_dnssec(qstate->env, iq->dp, 1234238106Sdes iq->deleg_msg, iq->qchase.qclass); 1235238106Sdes 1236238106Sdes /* If the RD flag wasn't set, then we just finish with the 1237238106Sdes * cached referral as the response. */ 1238238106Sdes if(!(qstate->query_flags & BIT_RD)) { 1239238106Sdes iq->response = iq->deleg_msg; 1240238106Sdes if(verbosity >= VERB_ALGO) 1241238106Sdes log_dns_msg("no RD requested, using delegation msg", 1242238106Sdes &iq->response->qinfo, iq->response->rep); 1243238106Sdes if(qstate->reply_origin) 1244238106Sdes sock_list_insert(&qstate->reply_origin, NULL, 0, qstate->region); 1245238106Sdes return final_state(iq); 1246238106Sdes } 1247238106Sdes /* After this point, unset the RD flag -- this query is going to 1248238106Sdes * be sent to an auth. server. */ 1249238106Sdes iq->chase_flags &= ~BIT_RD; 1250238106Sdes 1251238106Sdes /* if dnssec expected, fetch key for the trust-anchor or cached-DS */ 1252238106Sdes if(iq->dnssec_expected && qstate->env->cfg->prefetch_key && 1253238106Sdes !(qstate->query_flags&BIT_CD)) { 1254238106Sdes generate_dnskey_prefetch(qstate, iq, id); 1255238106Sdes fptr_ok(fptr_whitelist_modenv_detach_subs( 1256238106Sdes qstate->env->detach_subs)); 1257238106Sdes (*qstate->env->detach_subs)(qstate); 1258238106Sdes } 1259238106Sdes 1260238106Sdes /* Jump to the next state. */ 1261238106Sdes return next_state(iq, QUERYTARGETS_STATE); 1262238106Sdes} 1263238106Sdes 1264238106Sdes/** 1265238106Sdes * Given a basic query, generate a parent-side "target" query. 1266238106Sdes * These are subordinate queries for missing delegation point target addresses, 1267238106Sdes * for which only the parent of the delegation provides correct IP addresses. 1268238106Sdes * 1269238106Sdes * @param qstate: query state. 1270238106Sdes * @param iq: iterator query state. 1271238106Sdes * @param id: module id. 1272238106Sdes * @param name: target qname. 1273238106Sdes * @param namelen: target qname length. 1274238106Sdes * @param qtype: target qtype (either A or AAAA). 1275238106Sdes * @param qclass: target qclass. 1276238106Sdes * @return true on success, false on failure. 1277238106Sdes */ 1278238106Sdesstatic int 1279238106Sdesgenerate_parentside_target_query(struct module_qstate* qstate, 1280238106Sdes struct iter_qstate* iq, int id, uint8_t* name, size_t namelen, 1281238106Sdes uint16_t qtype, uint16_t qclass) 1282238106Sdes{ 1283238106Sdes struct module_qstate* subq; 1284238106Sdes if(!generate_sub_request(name, namelen, qtype, qclass, qstate, 1285238106Sdes id, iq, INIT_REQUEST_STATE, FINISHED_STATE, &subq, 0)) 1286238106Sdes return 0; 1287238106Sdes if(subq) { 1288238106Sdes struct iter_qstate* subiq = 1289238106Sdes (struct iter_qstate*)subq->minfo[id]; 1290238106Sdes /* blacklist the cache - we want to fetch parent stuff */ 1291238106Sdes sock_list_insert(&subq->blacklist, NULL, 0, subq->region); 1292238106Sdes subiq->query_for_pside_glue = 1; 1293238106Sdes if(dname_subdomain_c(name, iq->dp->name)) { 1294238106Sdes subiq->dp = delegpt_copy(iq->dp, subq->region); 1295238106Sdes subiq->dnssec_expected = iter_indicates_dnssec( 1296238106Sdes qstate->env, subiq->dp, NULL, 1297238106Sdes subq->qinfo.qclass); 1298238106Sdes subiq->refetch_glue = 1; 1299238106Sdes } else { 1300238106Sdes subiq->dp = dns_cache_find_delegation(qstate->env, 1301238106Sdes name, namelen, qtype, qclass, subq->region, 1302238106Sdes &subiq->deleg_msg, 1303238106Sdes *qstate->env->now+subq->prefetch_leeway); 1304238106Sdes /* if no dp, then it's from root, refetch unneeded */ 1305238106Sdes if(subiq->dp) { 1306238106Sdes subiq->dnssec_expected = iter_indicates_dnssec( 1307238106Sdes qstate->env, subiq->dp, NULL, 1308238106Sdes subq->qinfo.qclass); 1309238106Sdes subiq->refetch_glue = 1; 1310238106Sdes } 1311238106Sdes } 1312238106Sdes } 1313238106Sdes log_nametypeclass(VERB_QUERY, "new pside target", name, qtype, qclass); 1314238106Sdes return 1; 1315238106Sdes} 1316238106Sdes 1317238106Sdes/** 1318238106Sdes * Given a basic query, generate a "target" query. These are subordinate 1319238106Sdes * queries for missing delegation point target addresses. 1320238106Sdes * 1321238106Sdes * @param qstate: query state. 1322238106Sdes * @param iq: iterator query state. 1323238106Sdes * @param id: module id. 1324238106Sdes * @param name: target qname. 1325238106Sdes * @param namelen: target qname length. 1326238106Sdes * @param qtype: target qtype (either A or AAAA). 1327238106Sdes * @param qclass: target qclass. 1328238106Sdes * @return true on success, false on failure. 1329238106Sdes */ 1330238106Sdesstatic int 1331238106Sdesgenerate_target_query(struct module_qstate* qstate, struct iter_qstate* iq, 1332238106Sdes int id, uint8_t* name, size_t namelen, uint16_t qtype, uint16_t qclass) 1333238106Sdes{ 1334238106Sdes struct module_qstate* subq; 1335238106Sdes if(!generate_sub_request(name, namelen, qtype, qclass, qstate, 1336238106Sdes id, iq, INIT_REQUEST_STATE, FINISHED_STATE, &subq, 0)) 1337238106Sdes return 0; 1338238106Sdes log_nametypeclass(VERB_QUERY, "new target", name, qtype, qclass); 1339238106Sdes return 1; 1340238106Sdes} 1341238106Sdes 1342238106Sdes/** 1343238106Sdes * Given an event at a certain state, generate zero or more target queries 1344238106Sdes * for it's current delegation point. 1345238106Sdes * 1346238106Sdes * @param qstate: query state. 1347238106Sdes * @param iq: iterator query state. 1348238106Sdes * @param ie: iterator shared global environment. 1349238106Sdes * @param id: module id. 1350238106Sdes * @param maxtargets: The maximum number of targets to query for. 1351238106Sdes * if it is negative, there is no maximum number of targets. 1352238106Sdes * @param num: returns the number of queries generated and processed, 1353238106Sdes * which may be zero if there were no missing targets. 1354238106Sdes * @return false on error. 1355238106Sdes */ 1356238106Sdesstatic int 1357238106Sdesquery_for_targets(struct module_qstate* qstate, struct iter_qstate* iq, 1358238106Sdes struct iter_env* ie, int id, int maxtargets, int* num) 1359238106Sdes{ 1360238106Sdes int query_count = 0; 1361238106Sdes struct delegpt_ns* ns; 1362238106Sdes int missing; 1363238106Sdes int toget = 0; 1364238106Sdes 1365238106Sdes if(iq->depth == ie->max_dependency_depth) 1366238106Sdes return 0; 1367275854Sdelphij if(iq->depth > 0 && iq->target_count && 1368275854Sdelphij iq->target_count[1] > MAX_TARGET_COUNT) { 1369275854Sdelphij verbose(VERB_QUERY, "request has exceeded the maximum " 1370275854Sdelphij "number of glue fetches %d", iq->target_count[1]); 1371275854Sdelphij return 0; 1372275854Sdelphij } 1373238106Sdes 1374238106Sdes iter_mark_cycle_targets(qstate, iq->dp); 1375238106Sdes missing = (int)delegpt_count_missing_targets(iq->dp); 1376238106Sdes log_assert(maxtargets != 0); /* that would not be useful */ 1377238106Sdes 1378238106Sdes /* Generate target requests. Basically, any missing targets 1379238106Sdes * are queried for here, regardless if it is necessary to do 1380238106Sdes * so to continue processing. */ 1381238106Sdes if(maxtargets < 0 || maxtargets > missing) 1382238106Sdes toget = missing; 1383238106Sdes else toget = maxtargets; 1384238106Sdes if(toget == 0) { 1385238106Sdes *num = 0; 1386238106Sdes return 1; 1387238106Sdes } 1388238106Sdes /* select 'toget' items from the total of 'missing' items */ 1389238106Sdes log_assert(toget <= missing); 1390238106Sdes 1391238106Sdes /* loop over missing targets */ 1392238106Sdes for(ns = iq->dp->nslist; ns; ns = ns->next) { 1393238106Sdes if(ns->resolved) 1394238106Sdes continue; 1395238106Sdes 1396238106Sdes /* randomly select this item with probability toget/missing */ 1397238106Sdes if(!iter_ns_probability(qstate->env->rnd, toget, missing)) { 1398238106Sdes /* do not select this one, next; select toget number 1399238106Sdes * of items from a list one less in size */ 1400238106Sdes missing --; 1401238106Sdes continue; 1402238106Sdes } 1403238106Sdes 1404238106Sdes if(ie->supports_ipv6 && !ns->got6) { 1405238106Sdes /* Send the AAAA request. */ 1406238106Sdes if(!generate_target_query(qstate, iq, id, 1407238106Sdes ns->name, ns->namelen, 1408238106Sdes LDNS_RR_TYPE_AAAA, iq->qchase.qclass)) { 1409238106Sdes *num = query_count; 1410238106Sdes if(query_count > 0) 1411238106Sdes qstate->ext_state[id] = module_wait_subquery; 1412238106Sdes return 0; 1413238106Sdes } 1414238106Sdes query_count++; 1415238106Sdes } 1416238106Sdes /* Send the A request. */ 1417238106Sdes if(ie->supports_ipv4 && !ns->got4) { 1418238106Sdes if(!generate_target_query(qstate, iq, id, 1419238106Sdes ns->name, ns->namelen, 1420238106Sdes LDNS_RR_TYPE_A, iq->qchase.qclass)) { 1421238106Sdes *num = query_count; 1422238106Sdes if(query_count > 0) 1423238106Sdes qstate->ext_state[id] = module_wait_subquery; 1424238106Sdes return 0; 1425238106Sdes } 1426238106Sdes query_count++; 1427238106Sdes } 1428238106Sdes 1429238106Sdes /* mark this target as in progress. */ 1430238106Sdes ns->resolved = 1; 1431238106Sdes missing--; 1432238106Sdes toget--; 1433238106Sdes if(toget == 0) 1434238106Sdes break; 1435238106Sdes } 1436238106Sdes *num = query_count; 1437238106Sdes if(query_count > 0) 1438238106Sdes qstate->ext_state[id] = module_wait_subquery; 1439238106Sdes 1440238106Sdes return 1; 1441238106Sdes} 1442238106Sdes 1443238106Sdes/** 1444238106Sdes * Called by processQueryTargets when it would like extra targets to query 1445238106Sdes * but it seems to be out of options. At last resort some less appealing 1446238106Sdes * options are explored. If there are no more options, the result is SERVFAIL 1447238106Sdes * 1448238106Sdes * @param qstate: query state. 1449238106Sdes * @param iq: iterator query state. 1450238106Sdes * @param ie: iterator shared global environment. 1451238106Sdes * @param id: module id. 1452238106Sdes * @return true if the event requires more request processing immediately, 1453238106Sdes * false if not. 1454238106Sdes */ 1455238106Sdesstatic int 1456238106SdesprocessLastResort(struct module_qstate* qstate, struct iter_qstate* iq, 1457238106Sdes struct iter_env* ie, int id) 1458238106Sdes{ 1459238106Sdes struct delegpt_ns* ns; 1460238106Sdes int query_count = 0; 1461238106Sdes verbose(VERB_ALGO, "No more query targets, attempting last resort"); 1462238106Sdes log_assert(iq->dp); 1463238106Sdes 1464249141Sdes if(!iq->dp->has_parent_side_NS && dname_is_root(iq->dp->name)) { 1465249141Sdes struct delegpt* p = hints_lookup_root(qstate->env->hints, 1466249141Sdes iq->qchase.qclass); 1467249141Sdes if(p) { 1468249141Sdes struct delegpt_ns* ns; 1469249141Sdes struct delegpt_addr* a; 1470249141Sdes iq->chase_flags &= ~BIT_RD; /* go to authorities */ 1471249141Sdes for(ns = p->nslist; ns; ns=ns->next) { 1472249141Sdes (void)delegpt_add_ns(iq->dp, qstate->region, 1473249141Sdes ns->name, (int)ns->lame); 1474249141Sdes } 1475249141Sdes for(a = p->target_list; a; a=a->next_target) { 1476249141Sdes (void)delegpt_add_addr(iq->dp, qstate->region, 1477249141Sdes &a->addr, a->addrlen, a->bogus, 1478249141Sdes a->lame); 1479249141Sdes } 1480249141Sdes } 1481249141Sdes iq->dp->has_parent_side_NS = 1; 1482249141Sdes } else if(!iq->dp->has_parent_side_NS) { 1483238106Sdes if(!iter_lookup_parent_NS_from_cache(qstate->env, iq->dp, 1484238106Sdes qstate->region, &qstate->qinfo) 1485238106Sdes || !iq->dp->has_parent_side_NS) { 1486238106Sdes /* if: malloc failure in lookup go up to try */ 1487238106Sdes /* if: no parent NS in cache - go up one level */ 1488238106Sdes verbose(VERB_ALGO, "try to grab parent NS"); 1489238106Sdes iq->store_parent_NS = iq->dp; 1490249141Sdes iq->chase_flags &= ~BIT_RD; /* go to authorities */ 1491238106Sdes iq->deleg_msg = NULL; 1492238106Sdes iq->refetch_glue = 1; 1493238106Sdes iq->query_restart_count++; 1494238106Sdes iq->sent_count = 0; 1495238106Sdes return next_state(iq, INIT_REQUEST_STATE); 1496238106Sdes } 1497238106Sdes } 1498238106Sdes /* see if that makes new names available */ 1499238106Sdes if(!cache_fill_missing(qstate->env, iq->qchase.qclass, 1500238106Sdes qstate->region, iq->dp)) 1501238106Sdes log_err("out of memory in cache_fill_missing"); 1502238106Sdes if(iq->dp->usable_list) { 1503238106Sdes verbose(VERB_ALGO, "try parent-side-name, w. glue from cache"); 1504238106Sdes return next_state(iq, QUERYTARGETS_STATE); 1505238106Sdes } 1506238106Sdes /* try to fill out parent glue from cache */ 1507238106Sdes if(iter_lookup_parent_glue_from_cache(qstate->env, iq->dp, 1508238106Sdes qstate->region, &qstate->qinfo)) { 1509238106Sdes /* got parent stuff from cache, see if we can continue */ 1510238106Sdes verbose(VERB_ALGO, "try parent-side glue from cache"); 1511238106Sdes return next_state(iq, QUERYTARGETS_STATE); 1512238106Sdes } 1513238106Sdes /* query for an extra name added by the parent-NS record */ 1514238106Sdes if(delegpt_count_missing_targets(iq->dp) > 0) { 1515238106Sdes int qs = 0; 1516238106Sdes verbose(VERB_ALGO, "try parent-side target name"); 1517238106Sdes if(!query_for_targets(qstate, iq, ie, id, 1, &qs)) { 1518238106Sdes return error_response(qstate, id, LDNS_RCODE_SERVFAIL); 1519238106Sdes } 1520238106Sdes iq->num_target_queries += qs; 1521275854Sdelphij target_count_increase(iq, qs); 1522238106Sdes if(qs != 0) { 1523238106Sdes qstate->ext_state[id] = module_wait_subquery; 1524238106Sdes return 0; /* and wait for them */ 1525238106Sdes } 1526238106Sdes } 1527238106Sdes if(iq->depth == ie->max_dependency_depth) { 1528238106Sdes verbose(VERB_QUERY, "maxdepth and need more nameservers, fail"); 1529238106Sdes return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL); 1530238106Sdes } 1531275854Sdelphij if(iq->depth > 0 && iq->target_count && 1532275854Sdelphij iq->target_count[1] > MAX_TARGET_COUNT) { 1533275854Sdelphij verbose(VERB_QUERY, "request has exceeded the maximum " 1534275854Sdelphij "number of glue fetches %d", iq->target_count[1]); 1535275854Sdelphij return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL); 1536275854Sdelphij } 1537238106Sdes /* mark cycle targets for parent-side lookups */ 1538238106Sdes iter_mark_pside_cycle_targets(qstate, iq->dp); 1539238106Sdes /* see if we can issue queries to get nameserver addresses */ 1540238106Sdes /* this lookup is not randomized, but sequential. */ 1541238106Sdes for(ns = iq->dp->nslist; ns; ns = ns->next) { 1542238106Sdes /* query for parent-side A and AAAA for nameservers */ 1543238106Sdes if(ie->supports_ipv6 && !ns->done_pside6) { 1544238106Sdes /* Send the AAAA request. */ 1545238106Sdes if(!generate_parentside_target_query(qstate, iq, id, 1546238106Sdes ns->name, ns->namelen, 1547238106Sdes LDNS_RR_TYPE_AAAA, iq->qchase.qclass)) 1548238106Sdes return error_response(qstate, id, 1549238106Sdes LDNS_RCODE_SERVFAIL); 1550238106Sdes ns->done_pside6 = 1; 1551238106Sdes query_count++; 1552238106Sdes } 1553238106Sdes if(ie->supports_ipv4 && !ns->done_pside4) { 1554238106Sdes /* Send the A request. */ 1555238106Sdes if(!generate_parentside_target_query(qstate, iq, id, 1556238106Sdes ns->name, ns->namelen, 1557238106Sdes LDNS_RR_TYPE_A, iq->qchase.qclass)) 1558238106Sdes return error_response(qstate, id, 1559238106Sdes LDNS_RCODE_SERVFAIL); 1560238106Sdes ns->done_pside4 = 1; 1561238106Sdes query_count++; 1562238106Sdes } 1563238106Sdes if(query_count != 0) { /* suspend to await results */ 1564238106Sdes verbose(VERB_ALGO, "try parent-side glue lookup"); 1565238106Sdes iq->num_target_queries += query_count; 1566275854Sdelphij target_count_increase(iq, query_count); 1567238106Sdes qstate->ext_state[id] = module_wait_subquery; 1568238106Sdes return 0; 1569238106Sdes } 1570238106Sdes } 1571238106Sdes 1572238106Sdes /* if this was a parent-side glue query itself, then store that 1573238106Sdes * failure in cache. */ 1574238106Sdes if(iq->query_for_pside_glue && !iq->pside_glue) 1575238106Sdes iter_store_parentside_neg(qstate->env, &qstate->qinfo, 1576238106Sdes iq->deleg_msg?iq->deleg_msg->rep: 1577238106Sdes (iq->response?iq->response->rep:NULL)); 1578238106Sdes 1579238106Sdes verbose(VERB_QUERY, "out of query targets -- returning SERVFAIL"); 1580238106Sdes /* fail -- no more targets, no more hope of targets, no hope 1581238106Sdes * of a response. */ 1582238106Sdes return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL); 1583238106Sdes} 1584238106Sdes 1585238106Sdes/** 1586238106Sdes * Try to find the NS record set that will resolve a qtype DS query. Due 1587238106Sdes * to grandparent/grandchild reasons we did not get a proper lookup right 1588238106Sdes * away. We need to create type NS queries until we get the right parent 1589238106Sdes * for this lookup. We remove labels from the query to find the right point. 1590238106Sdes * If we end up at the old dp name, then there is no solution. 1591238106Sdes * 1592238106Sdes * @param qstate: query state. 1593238106Sdes * @param iq: iterator query state. 1594238106Sdes * @param id: module id. 1595238106Sdes * @return true if the event requires more immediate processing, false if 1596238106Sdes * not. This is generally only true when forwarding the request to 1597238106Sdes * the final state (i.e., on answer). 1598238106Sdes */ 1599238106Sdesstatic int 1600249141SdesprocessDSNSFind(struct module_qstate* qstate, struct iter_qstate* iq, int id) 1601238106Sdes{ 1602238106Sdes struct module_qstate* subq = NULL; 1603238106Sdes verbose(VERB_ALGO, "processDSNSFind"); 1604238106Sdes 1605238106Sdes if(!iq->dsns_point) { 1606238106Sdes /* initialize */ 1607238106Sdes iq->dsns_point = iq->qchase.qname; 1608238106Sdes iq->dsns_point_len = iq->qchase.qname_len; 1609238106Sdes } 1610238106Sdes /* robustcheck for internal error: we are not underneath the dp */ 1611238106Sdes if(!dname_subdomain_c(iq->dsns_point, iq->dp->name)) { 1612238106Sdes return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL); 1613238106Sdes } 1614238106Sdes 1615238106Sdes /* go up one (more) step, until we hit the dp, if so, end */ 1616238106Sdes dname_remove_label(&iq->dsns_point, &iq->dsns_point_len); 1617238106Sdes if(query_dname_compare(iq->dsns_point, iq->dp->name) == 0) { 1618238106Sdes /* there was no inbetween nameserver, use the old delegation 1619238106Sdes * point again. And this time, because dsns_point is nonNULL 1620238106Sdes * we are going to accept the (bad) result */ 1621238106Sdes iq->state = QUERYTARGETS_STATE; 1622238106Sdes return 1; 1623238106Sdes } 1624238106Sdes iq->state = DSNS_FIND_STATE; 1625238106Sdes 1626238106Sdes /* spawn NS lookup (validation not needed, this is for DS lookup) */ 1627238106Sdes log_nametypeclass(VERB_ALGO, "fetch nameservers", 1628238106Sdes iq->dsns_point, LDNS_RR_TYPE_NS, iq->qchase.qclass); 1629238106Sdes if(!generate_sub_request(iq->dsns_point, iq->dsns_point_len, 1630238106Sdes LDNS_RR_TYPE_NS, iq->qchase.qclass, qstate, id, iq, 1631238106Sdes INIT_REQUEST_STATE, FINISHED_STATE, &subq, 0)) { 1632238106Sdes return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL); 1633238106Sdes } 1634238106Sdes 1635238106Sdes return 0; 1636238106Sdes} 1637238106Sdes 1638238106Sdes/** 1639238106Sdes * This is the request event state where the request will be sent to one of 1640238106Sdes * its current query targets. This state also handles issuing target lookup 1641238106Sdes * queries for missing target IP addresses. Queries typically iterate on 1642238106Sdes * this state, both when they are just trying different targets for a given 1643238106Sdes * delegation point, and when they change delegation points. This state 1644238106Sdes * roughly corresponds to RFC 1034 algorithm steps 3 and 4. 1645238106Sdes * 1646238106Sdes * @param qstate: query state. 1647238106Sdes * @param iq: iterator query state. 1648238106Sdes * @param ie: iterator shared global environment. 1649238106Sdes * @param id: module id. 1650238106Sdes * @return true if the event requires more request processing immediately, 1651238106Sdes * false if not. This state only returns true when it is generating 1652238106Sdes * a SERVFAIL response because the query has hit a dead end. 1653238106Sdes */ 1654238106Sdesstatic int 1655238106SdesprocessQueryTargets(struct module_qstate* qstate, struct iter_qstate* iq, 1656238106Sdes struct iter_env* ie, int id) 1657238106Sdes{ 1658238106Sdes int tf_policy; 1659238106Sdes struct delegpt_addr* target; 1660238106Sdes struct outbound_entry* outq; 1661238106Sdes 1662238106Sdes /* NOTE: a request will encounter this state for each target it 1663238106Sdes * needs to send a query to. That is, at least one per referral, 1664238106Sdes * more if some targets timeout or return throwaway answers. */ 1665238106Sdes 1666238106Sdes log_query_info(VERB_QUERY, "processQueryTargets:", &qstate->qinfo); 1667238106Sdes verbose(VERB_ALGO, "processQueryTargets: targetqueries %d, " 1668238106Sdes "currentqueries %d sentcount %d", iq->num_target_queries, 1669238106Sdes iq->num_current_queries, iq->sent_count); 1670238106Sdes 1671238106Sdes /* Make sure that we haven't run away */ 1672238106Sdes /* FIXME: is this check even necessary? */ 1673238106Sdes if(iq->referral_count > MAX_REFERRAL_COUNT) { 1674238106Sdes verbose(VERB_QUERY, "request has exceeded the maximum " 1675238106Sdes "number of referrrals with %d", iq->referral_count); 1676238106Sdes return error_response(qstate, id, LDNS_RCODE_SERVFAIL); 1677238106Sdes } 1678238106Sdes if(iq->sent_count > MAX_SENT_COUNT) { 1679238106Sdes verbose(VERB_QUERY, "request has exceeded the maximum " 1680238106Sdes "number of sends with %d", iq->sent_count); 1681238106Sdes return error_response(qstate, id, LDNS_RCODE_SERVFAIL); 1682238106Sdes } 1683238106Sdes 1684238106Sdes /* Make sure we have a delegation point, otherwise priming failed 1685238106Sdes * or another failure occurred */ 1686238106Sdes if(!iq->dp) { 1687238106Sdes verbose(VERB_QUERY, "Failed to get a delegation, giving up"); 1688238106Sdes return error_response(qstate, id, LDNS_RCODE_SERVFAIL); 1689238106Sdes } 1690238106Sdes if(!ie->supports_ipv6) 1691238106Sdes delegpt_no_ipv6(iq->dp); 1692238106Sdes if(!ie->supports_ipv4) 1693238106Sdes delegpt_no_ipv4(iq->dp); 1694238106Sdes delegpt_log(VERB_ALGO, iq->dp); 1695238106Sdes 1696238106Sdes if(iq->num_current_queries>0) { 1697238106Sdes /* already busy answering a query, this restart is because 1698238106Sdes * more delegpt addrs became available, wait for existing 1699238106Sdes * query. */ 1700238106Sdes verbose(VERB_ALGO, "woke up, but wait for outstanding query"); 1701238106Sdes qstate->ext_state[id] = module_wait_reply; 1702238106Sdes return 0; 1703238106Sdes } 1704238106Sdes 1705238106Sdes tf_policy = 0; 1706238106Sdes /* < not <=, because although the array is large enough for <=, the 1707238106Sdes * generated query will immediately be discarded due to depth and 1708238106Sdes * that servfail is cached, which is not good as opportunism goes. */ 1709238106Sdes if(iq->depth < ie->max_dependency_depth 1710238106Sdes && iq->sent_count < TARGET_FETCH_STOP) { 1711238106Sdes tf_policy = ie->target_fetch_policy[iq->depth]; 1712238106Sdes } 1713238106Sdes 1714238106Sdes /* if in 0x20 fallback get as many targets as possible */ 1715238106Sdes if(iq->caps_fallback) { 1716238106Sdes int extra = 0; 1717238106Sdes size_t naddr, nres, navail; 1718238106Sdes if(!query_for_targets(qstate, iq, ie, id, -1, &extra)) { 1719238106Sdes return error_response(qstate, id, LDNS_RCODE_SERVFAIL); 1720238106Sdes } 1721238106Sdes iq->num_target_queries += extra; 1722275854Sdelphij target_count_increase(iq, extra); 1723238106Sdes if(iq->num_target_queries > 0) { 1724238106Sdes /* wait to get all targets, we want to try em */ 1725238106Sdes verbose(VERB_ALGO, "wait for all targets for fallback"); 1726238106Sdes qstate->ext_state[id] = module_wait_reply; 1727238106Sdes return 0; 1728238106Sdes } 1729238106Sdes /* did we do enough fallback queries already? */ 1730238106Sdes delegpt_count_addr(iq->dp, &naddr, &nres, &navail); 1731238106Sdes /* the current caps_server is the number of fallbacks sent. 1732238106Sdes * the original query is one that matched too, so we have 1733238106Sdes * caps_server+1 number of matching queries now */ 1734238106Sdes if(iq->caps_server+1 >= naddr*3 || 1735238106Sdes iq->caps_server+1 >= MAX_SENT_COUNT) { 1736238106Sdes /* we're done, process the response */ 1737238106Sdes verbose(VERB_ALGO, "0x20 fallback had %d responses " 1738238106Sdes "match for %d wanted, done.", 1739238106Sdes (int)iq->caps_server+1, (int)naddr*3); 1740238106Sdes iq->caps_fallback = 0; 1741238106Sdes iter_dec_attempts(iq->dp, 3); /* space for fallback */ 1742238106Sdes iq->num_current_queries++; /* RespState decrements it*/ 1743238106Sdes iq->referral_count++; /* make sure we don't loop */ 1744238106Sdes iq->sent_count = 0; 1745238106Sdes iq->state = QUERY_RESP_STATE; 1746238106Sdes return 1; 1747238106Sdes } 1748238106Sdes verbose(VERB_ALGO, "0x20 fallback number %d", 1749238106Sdes (int)iq->caps_server); 1750238106Sdes 1751238106Sdes /* if there is a policy to fetch missing targets 1752238106Sdes * opportunistically, do it. we rely on the fact that once a 1753238106Sdes * query (or queries) for a missing name have been issued, 1754238106Sdes * they will not show up again. */ 1755238106Sdes } else if(tf_policy != 0) { 1756238106Sdes int extra = 0; 1757238106Sdes verbose(VERB_ALGO, "attempt to get extra %d targets", 1758238106Sdes tf_policy); 1759238106Sdes (void)query_for_targets(qstate, iq, ie, id, tf_policy, &extra); 1760238106Sdes /* errors ignored, these targets are not strictly necessary for 1761238106Sdes * this result, we do not have to reply with SERVFAIL */ 1762238106Sdes iq->num_target_queries += extra; 1763275854Sdelphij target_count_increase(iq, extra); 1764238106Sdes } 1765238106Sdes 1766238106Sdes /* Add the current set of unused targets to our queue. */ 1767238106Sdes delegpt_add_unused_targets(iq->dp); 1768238106Sdes 1769238106Sdes /* Select the next usable target, filtering out unsuitable targets. */ 1770238106Sdes target = iter_server_selection(ie, qstate->env, iq->dp, 1771238106Sdes iq->dp->name, iq->dp->namelen, iq->qchase.qtype, 1772238106Sdes &iq->dnssec_lame_query, &iq->chase_to_rd, 1773238106Sdes iq->num_target_queries, qstate->blacklist); 1774238106Sdes 1775238106Sdes /* If no usable target was selected... */ 1776238106Sdes if(!target) { 1777238106Sdes /* Here we distinguish between three states: generate a new 1778238106Sdes * target query, just wait, or quit (with a SERVFAIL). 1779238106Sdes * We have the following information: number of active 1780238106Sdes * target queries, number of active current queries, 1781238106Sdes * the presence of missing targets at this delegation 1782238106Sdes * point, and the given query target policy. */ 1783238106Sdes 1784238106Sdes /* Check for the wait condition. If this is true, then 1785238106Sdes * an action must be taken. */ 1786238106Sdes if(iq->num_target_queries==0 && iq->num_current_queries==0) { 1787238106Sdes /* If there is nothing to wait for, then we need 1788238106Sdes * to distinguish between generating (a) new target 1789238106Sdes * query, or failing. */ 1790238106Sdes if(delegpt_count_missing_targets(iq->dp) > 0) { 1791238106Sdes int qs = 0; 1792238106Sdes verbose(VERB_ALGO, "querying for next " 1793238106Sdes "missing target"); 1794238106Sdes if(!query_for_targets(qstate, iq, ie, id, 1795238106Sdes 1, &qs)) { 1796238106Sdes return error_response(qstate, id, 1797238106Sdes LDNS_RCODE_SERVFAIL); 1798238106Sdes } 1799238106Sdes if(qs == 0 && 1800238106Sdes delegpt_count_missing_targets(iq->dp) == 0){ 1801238106Sdes /* it looked like there were missing 1802238106Sdes * targets, but they did not turn up. 1803238106Sdes * Try the bad choices again (if any), 1804238106Sdes * when we get back here missing==0, 1805238106Sdes * so this is not a loop. */ 1806238106Sdes return 1; 1807238106Sdes } 1808238106Sdes iq->num_target_queries += qs; 1809275854Sdelphij target_count_increase(iq, qs); 1810238106Sdes } 1811238106Sdes /* Since a target query might have been made, we 1812238106Sdes * need to check again. */ 1813238106Sdes if(iq->num_target_queries == 0) { 1814238106Sdes return processLastResort(qstate, iq, ie, id); 1815238106Sdes } 1816238106Sdes } 1817238106Sdes 1818238106Sdes /* otherwise, we have no current targets, so submerge 1819238106Sdes * until one of the target or direct queries return. */ 1820238106Sdes if(iq->num_target_queries>0 && iq->num_current_queries>0) { 1821238106Sdes verbose(VERB_ALGO, "no current targets -- waiting " 1822238106Sdes "for %d targets to resolve or %d outstanding" 1823238106Sdes " queries to respond", iq->num_target_queries, 1824238106Sdes iq->num_current_queries); 1825238106Sdes qstate->ext_state[id] = module_wait_reply; 1826238106Sdes } else if(iq->num_target_queries>0) { 1827238106Sdes verbose(VERB_ALGO, "no current targets -- waiting " 1828238106Sdes "for %d targets to resolve.", 1829238106Sdes iq->num_target_queries); 1830238106Sdes qstate->ext_state[id] = module_wait_subquery; 1831238106Sdes } else { 1832238106Sdes verbose(VERB_ALGO, "no current targets -- waiting " 1833238106Sdes "for %d outstanding queries to respond.", 1834238106Sdes iq->num_current_queries); 1835238106Sdes qstate->ext_state[id] = module_wait_reply; 1836238106Sdes } 1837238106Sdes return 0; 1838238106Sdes } 1839238106Sdes 1840238106Sdes /* We have a valid target. */ 1841238106Sdes if(verbosity >= VERB_QUERY) { 1842238106Sdes log_query_info(VERB_QUERY, "sending query:", &iq->qchase); 1843238106Sdes log_name_addr(VERB_QUERY, "sending to target:", iq->dp->name, 1844238106Sdes &target->addr, target->addrlen); 1845238106Sdes verbose(VERB_ALGO, "dnssec status: %s%s", 1846238106Sdes iq->dnssec_expected?"expected": "not expected", 1847238106Sdes iq->dnssec_lame_query?" but lame_query anyway": ""); 1848238106Sdes } 1849238106Sdes fptr_ok(fptr_whitelist_modenv_send_query(qstate->env->send_query)); 1850238106Sdes outq = (*qstate->env->send_query)( 1851238106Sdes iq->qchase.qname, iq->qchase.qname_len, 1852238106Sdes iq->qchase.qtype, iq->qchase.qclass, 1853238106Sdes iq->chase_flags | (iq->chase_to_rd?BIT_RD:0), EDNS_DO|BIT_CD, 1854238106Sdes iq->dnssec_expected, &target->addr, target->addrlen, 1855238106Sdes iq->dp->name, iq->dp->namelen, qstate); 1856238106Sdes if(!outq) { 1857238106Sdes log_addr(VERB_DETAIL, "error sending query to auth server", 1858238106Sdes &target->addr, target->addrlen); 1859238106Sdes return next_state(iq, QUERYTARGETS_STATE); 1860238106Sdes } 1861238106Sdes outbound_list_insert(&iq->outlist, outq); 1862238106Sdes iq->num_current_queries++; 1863238106Sdes iq->sent_count++; 1864238106Sdes qstate->ext_state[id] = module_wait_reply; 1865238106Sdes 1866238106Sdes return 0; 1867238106Sdes} 1868238106Sdes 1869238106Sdes/** find NS rrset in given list */ 1870238106Sdesstatic struct ub_packed_rrset_key* 1871238106Sdesfind_NS(struct reply_info* rep, size_t from, size_t to) 1872238106Sdes{ 1873238106Sdes size_t i; 1874238106Sdes for(i=from; i<to; i++) { 1875238106Sdes if(ntohs(rep->rrsets[i]->rk.type) == LDNS_RR_TYPE_NS) 1876238106Sdes return rep->rrsets[i]; 1877238106Sdes } 1878238106Sdes return NULL; 1879238106Sdes} 1880238106Sdes 1881238106Sdes 1882238106Sdes/** 1883238106Sdes * Process the query response. All queries end up at this state first. This 1884238106Sdes * process generally consists of analyzing the response and routing the 1885238106Sdes * event to the next state (either bouncing it back to a request state, or 1886238106Sdes * terminating the processing for this event). 1887238106Sdes * 1888238106Sdes * @param qstate: query state. 1889238106Sdes * @param iq: iterator query state. 1890238106Sdes * @param id: module id. 1891238106Sdes * @return true if the event requires more immediate processing, false if 1892238106Sdes * not. This is generally only true when forwarding the request to 1893238106Sdes * the final state (i.e., on answer). 1894238106Sdes */ 1895238106Sdesstatic int 1896238106SdesprocessQueryResponse(struct module_qstate* qstate, struct iter_qstate* iq, 1897238106Sdes int id) 1898238106Sdes{ 1899238106Sdes int dnsseclame = 0; 1900238106Sdes enum response_type type; 1901238106Sdes iq->num_current_queries--; 1902238106Sdes if(iq->response == NULL) { 1903238106Sdes iq->chase_to_rd = 0; 1904238106Sdes iq->dnssec_lame_query = 0; 1905238106Sdes verbose(VERB_ALGO, "query response was timeout"); 1906238106Sdes return next_state(iq, QUERYTARGETS_STATE); 1907238106Sdes } 1908238106Sdes type = response_type_from_server( 1909238106Sdes (int)((iq->chase_flags&BIT_RD) || iq->chase_to_rd), 1910238106Sdes iq->response, &iq->qchase, iq->dp); 1911238106Sdes iq->chase_to_rd = 0; 1912238106Sdes if(type == RESPONSE_TYPE_REFERRAL && (iq->chase_flags&BIT_RD)) { 1913238106Sdes /* When forwarding (RD bit is set), we handle referrals 1914238106Sdes * differently. No queries should be sent elsewhere */ 1915238106Sdes type = RESPONSE_TYPE_ANSWER; 1916238106Sdes } 1917238106Sdes if(iq->dnssec_expected && !iq->dnssec_lame_query && 1918238106Sdes !(iq->chase_flags&BIT_RD) 1919238106Sdes && type != RESPONSE_TYPE_LAME 1920238106Sdes && type != RESPONSE_TYPE_REC_LAME 1921238106Sdes && type != RESPONSE_TYPE_THROWAWAY 1922238106Sdes && type != RESPONSE_TYPE_UNTYPED) { 1923238106Sdes /* a possible answer, see if it is missing DNSSEC */ 1924238106Sdes /* but not when forwarding, so we dont mark fwder lame */ 1925238106Sdes /* also make sure the answer is from the zone we expected, 1926238106Sdes * otherwise, (due to parent,child on same server), we 1927238106Sdes * might mark the server,zone lame inappropriately */ 1928238106Sdes if(!iter_msg_has_dnssec(iq->response) && 1929238106Sdes iter_msg_from_zone(iq->response, iq->dp, type, 1930238106Sdes iq->qchase.qclass)) { 1931238106Sdes type = RESPONSE_TYPE_LAME; 1932238106Sdes dnsseclame = 1; 1933238106Sdes } 1934238106Sdes } else iq->dnssec_lame_query = 0; 1935238106Sdes /* see if referral brings us close to the target */ 1936238106Sdes if(type == RESPONSE_TYPE_REFERRAL) { 1937238106Sdes struct ub_packed_rrset_key* ns = find_NS( 1938238106Sdes iq->response->rep, iq->response->rep->an_numrrsets, 1939238106Sdes iq->response->rep->an_numrrsets 1940238106Sdes + iq->response->rep->ns_numrrsets); 1941238106Sdes if(!ns) ns = find_NS(iq->response->rep, 0, 1942238106Sdes iq->response->rep->an_numrrsets); 1943238106Sdes if(!ns || !dname_strict_subdomain_c(ns->rk.dname, iq->dp->name) 1944238106Sdes || !dname_subdomain_c(iq->qchase.qname, ns->rk.dname)){ 1945238106Sdes verbose(VERB_ALGO, "bad referral, throwaway"); 1946238106Sdes type = RESPONSE_TYPE_THROWAWAY; 1947238106Sdes } else 1948238106Sdes iter_scrub_ds(iq->response, ns, iq->dp->name); 1949238106Sdes } else iter_scrub_ds(iq->response, NULL, NULL); 1950238106Sdes 1951238106Sdes /* handle each of the type cases */ 1952238106Sdes if(type == RESPONSE_TYPE_ANSWER) { 1953238106Sdes /* ANSWER type responses terminate the query algorithm, 1954238106Sdes * so they sent on their */ 1955238106Sdes if(verbosity >= VERB_DETAIL) { 1956238106Sdes verbose(VERB_DETAIL, "query response was %s", 1957238106Sdes FLAGS_GET_RCODE(iq->response->rep->flags) 1958238106Sdes ==LDNS_RCODE_NXDOMAIN?"NXDOMAIN ANSWER": 1959238106Sdes (iq->response->rep->an_numrrsets?"ANSWER": 1960238106Sdes "nodata ANSWER")); 1961238106Sdes } 1962238106Sdes /* if qtype is DS, check we have the right level of answer, 1963238106Sdes * like grandchild answer but we need the middle, reject it */ 1964238106Sdes if(iq->qchase.qtype == LDNS_RR_TYPE_DS && !iq->dsns_point 1965238106Sdes && !(iq->chase_flags&BIT_RD) 1966238106Sdes && iter_ds_toolow(iq->response, iq->dp) 1967249141Sdes && iter_dp_cangodown(&iq->qchase, iq->dp)) { 1968249141Sdes /* close down outstanding requests to be discarded */ 1969249141Sdes outbound_list_clear(&iq->outlist); 1970249141Sdes iq->num_current_queries = 0; 1971249141Sdes fptr_ok(fptr_whitelist_modenv_detach_subs( 1972249141Sdes qstate->env->detach_subs)); 1973249141Sdes (*qstate->env->detach_subs)(qstate); 1974249141Sdes iq->num_target_queries = 0; 1975238106Sdes return processDSNSFind(qstate, iq, id); 1976249141Sdes } 1977249141Sdes iter_dns_store(qstate->env, &iq->response->qinfo, 1978238106Sdes iq->response->rep, 0, qstate->prefetch_leeway, 1979238106Sdes iq->dp&&iq->dp->has_parent_side_NS, 1980249141Sdes qstate->region); 1981238106Sdes /* close down outstanding requests to be discarded */ 1982238106Sdes outbound_list_clear(&iq->outlist); 1983238106Sdes iq->num_current_queries = 0; 1984238106Sdes fptr_ok(fptr_whitelist_modenv_detach_subs( 1985238106Sdes qstate->env->detach_subs)); 1986238106Sdes (*qstate->env->detach_subs)(qstate); 1987238106Sdes iq->num_target_queries = 0; 1988238106Sdes if(qstate->reply) 1989238106Sdes sock_list_insert(&qstate->reply_origin, 1990238106Sdes &qstate->reply->addr, qstate->reply->addrlen, 1991238106Sdes qstate->region); 1992238106Sdes return final_state(iq); 1993238106Sdes } else if(type == RESPONSE_TYPE_REFERRAL) { 1994238106Sdes /* REFERRAL type responses get a reset of the 1995238106Sdes * delegation point, and back to the QUERYTARGETS_STATE. */ 1996238106Sdes verbose(VERB_DETAIL, "query response was REFERRAL"); 1997238106Sdes 1998238106Sdes /* if hardened, only store referral if we asked for it */ 1999238106Sdes if(!qstate->env->cfg->harden_referral_path || 2000238106Sdes ( qstate->qinfo.qtype == LDNS_RR_TYPE_NS 2001238106Sdes && (qstate->query_flags&BIT_RD) 2002238106Sdes && !(qstate->query_flags&BIT_CD) 2003238106Sdes /* we know that all other NS rrsets are scrubbed 2004238106Sdes * away, thus on referral only one is left. 2005238106Sdes * see if that equals the query name... */ 2006238106Sdes && ( /* auth section, but sometimes in answer section*/ 2007238106Sdes reply_find_rrset_section_ns(iq->response->rep, 2008238106Sdes iq->qchase.qname, iq->qchase.qname_len, 2009238106Sdes LDNS_RR_TYPE_NS, iq->qchase.qclass) 2010238106Sdes || reply_find_rrset_section_an(iq->response->rep, 2011238106Sdes iq->qchase.qname, iq->qchase.qname_len, 2012238106Sdes LDNS_RR_TYPE_NS, iq->qchase.qclass) 2013238106Sdes ) 2014238106Sdes )) { 2015238106Sdes /* Store the referral under the current query */ 2016238106Sdes /* no prefetch-leeway, since its not the answer */ 2017249141Sdes iter_dns_store(qstate->env, &iq->response->qinfo, 2018249141Sdes iq->response->rep, 1, 0, 0, NULL); 2019238106Sdes if(iq->store_parent_NS) 2020238106Sdes iter_store_parentside_NS(qstate->env, 2021238106Sdes iq->response->rep); 2022238106Sdes if(qstate->env->neg_cache) 2023238106Sdes val_neg_addreferral(qstate->env->neg_cache, 2024238106Sdes iq->response->rep, iq->dp->name); 2025238106Sdes } 2026238106Sdes /* store parent-side-in-zone-glue, if directly queried for */ 2027238106Sdes if(iq->query_for_pside_glue && !iq->pside_glue) { 2028238106Sdes iq->pside_glue = reply_find_rrset(iq->response->rep, 2029238106Sdes iq->qchase.qname, iq->qchase.qname_len, 2030238106Sdes iq->qchase.qtype, iq->qchase.qclass); 2031238106Sdes if(iq->pside_glue) { 2032238106Sdes log_rrset_key(VERB_ALGO, "found parent-side " 2033238106Sdes "glue", iq->pside_glue); 2034238106Sdes iter_store_parentside_rrset(qstate->env, 2035238106Sdes iq->pside_glue); 2036238106Sdes } 2037238106Sdes } 2038238106Sdes 2039238106Sdes /* Reset the event state, setting the current delegation 2040238106Sdes * point to the referral. */ 2041238106Sdes iq->deleg_msg = iq->response; 2042238106Sdes iq->dp = delegpt_from_message(iq->response, qstate->region); 2043238106Sdes if(!iq->dp) 2044238106Sdes return error_response(qstate, id, LDNS_RCODE_SERVFAIL); 2045238106Sdes if(!cache_fill_missing(qstate->env, iq->qchase.qclass, 2046238106Sdes qstate->region, iq->dp)) 2047238106Sdes return error_response(qstate, id, LDNS_RCODE_SERVFAIL); 2048238106Sdes if(iq->store_parent_NS && query_dname_compare(iq->dp->name, 2049238106Sdes iq->store_parent_NS->name) == 0) 2050238106Sdes iter_merge_retry_counts(iq->dp, iq->store_parent_NS); 2051238106Sdes delegpt_log(VERB_ALGO, iq->dp); 2052238106Sdes /* Count this as a referral. */ 2053238106Sdes iq->referral_count++; 2054238106Sdes iq->sent_count = 0; 2055238106Sdes /* see if the next dp is a trust anchor, or a DS was sent 2056238106Sdes * along, indicating dnssec is expected for next zone */ 2057238106Sdes iq->dnssec_expected = iter_indicates_dnssec(qstate->env, 2058238106Sdes iq->dp, iq->response, iq->qchase.qclass); 2059238106Sdes /* if dnssec, validating then also fetch the key for the DS */ 2060238106Sdes if(iq->dnssec_expected && qstate->env->cfg->prefetch_key && 2061238106Sdes !(qstate->query_flags&BIT_CD)) 2062238106Sdes generate_dnskey_prefetch(qstate, iq, id); 2063238106Sdes 2064238106Sdes /* spawn off NS and addr to auth servers for the NS we just 2065238106Sdes * got in the referral. This gets authoritative answer 2066238106Sdes * (answer section trust level) rrset. 2067238106Sdes * right after, we detach the subs, answer goes to cache. */ 2068238106Sdes if(qstate->env->cfg->harden_referral_path) 2069238106Sdes generate_ns_check(qstate, iq, id); 2070238106Sdes 2071238106Sdes /* stop current outstanding queries. 2072238106Sdes * FIXME: should the outstanding queries be waited for and 2073238106Sdes * handled? Say by a subquery that inherits the outbound_entry. 2074238106Sdes */ 2075238106Sdes outbound_list_clear(&iq->outlist); 2076238106Sdes iq->num_current_queries = 0; 2077238106Sdes fptr_ok(fptr_whitelist_modenv_detach_subs( 2078238106Sdes qstate->env->detach_subs)); 2079238106Sdes (*qstate->env->detach_subs)(qstate); 2080238106Sdes iq->num_target_queries = 0; 2081238106Sdes verbose(VERB_ALGO, "cleared outbound list for next round"); 2082238106Sdes return next_state(iq, QUERYTARGETS_STATE); 2083238106Sdes } else if(type == RESPONSE_TYPE_CNAME) { 2084238106Sdes uint8_t* sname = NULL; 2085238106Sdes size_t snamelen = 0; 2086238106Sdes /* CNAME type responses get a query restart (i.e., get a 2087238106Sdes * reset of the query state and go back to INIT_REQUEST_STATE). 2088238106Sdes */ 2089238106Sdes verbose(VERB_DETAIL, "query response was CNAME"); 2090238106Sdes if(verbosity >= VERB_ALGO) 2091238106Sdes log_dns_msg("cname msg", &iq->response->qinfo, 2092238106Sdes iq->response->rep); 2093238106Sdes /* if qtype is DS, check we have the right level of answer, 2094238106Sdes * like grandchild answer but we need the middle, reject it */ 2095238106Sdes if(iq->qchase.qtype == LDNS_RR_TYPE_DS && !iq->dsns_point 2096238106Sdes && !(iq->chase_flags&BIT_RD) 2097238106Sdes && iter_ds_toolow(iq->response, iq->dp) 2098249141Sdes && iter_dp_cangodown(&iq->qchase, iq->dp)) { 2099249141Sdes outbound_list_clear(&iq->outlist); 2100249141Sdes iq->num_current_queries = 0; 2101249141Sdes fptr_ok(fptr_whitelist_modenv_detach_subs( 2102249141Sdes qstate->env->detach_subs)); 2103249141Sdes (*qstate->env->detach_subs)(qstate); 2104249141Sdes iq->num_target_queries = 0; 2105238106Sdes return processDSNSFind(qstate, iq, id); 2106249141Sdes } 2107238106Sdes /* Process the CNAME response. */ 2108238106Sdes if(!handle_cname_response(qstate, iq, iq->response, 2109238106Sdes &sname, &snamelen)) 2110238106Sdes return error_response(qstate, id, LDNS_RCODE_SERVFAIL); 2111238106Sdes /* cache the CNAME response under the current query */ 2112238106Sdes /* NOTE : set referral=1, so that rrsets get stored but not 2113238106Sdes * the partial query answer (CNAME only). */ 2114238106Sdes /* prefetchleeway applied because this updates answer parts */ 2115249141Sdes iter_dns_store(qstate->env, &iq->response->qinfo, 2116238106Sdes iq->response->rep, 1, qstate->prefetch_leeway, 2117249141Sdes iq->dp&&iq->dp->has_parent_side_NS, NULL); 2118238106Sdes /* set the current request's qname to the new value. */ 2119238106Sdes iq->qchase.qname = sname; 2120238106Sdes iq->qchase.qname_len = snamelen; 2121238106Sdes /* Clear the query state, since this is a query restart. */ 2122238106Sdes iq->deleg_msg = NULL; 2123238106Sdes iq->dp = NULL; 2124238106Sdes iq->dsns_point = NULL; 2125238106Sdes /* Note the query restart. */ 2126238106Sdes iq->query_restart_count++; 2127238106Sdes iq->sent_count = 0; 2128238106Sdes 2129238106Sdes /* stop current outstanding queries. 2130238106Sdes * FIXME: should the outstanding queries be waited for and 2131238106Sdes * handled? Say by a subquery that inherits the outbound_entry. 2132238106Sdes */ 2133238106Sdes outbound_list_clear(&iq->outlist); 2134238106Sdes iq->num_current_queries = 0; 2135238106Sdes fptr_ok(fptr_whitelist_modenv_detach_subs( 2136238106Sdes qstate->env->detach_subs)); 2137238106Sdes (*qstate->env->detach_subs)(qstate); 2138238106Sdes iq->num_target_queries = 0; 2139238106Sdes if(qstate->reply) 2140238106Sdes sock_list_insert(&qstate->reply_origin, 2141238106Sdes &qstate->reply->addr, qstate->reply->addrlen, 2142238106Sdes qstate->region); 2143238106Sdes verbose(VERB_ALGO, "cleared outbound list for query restart"); 2144238106Sdes /* go to INIT_REQUEST_STATE for new qname. */ 2145238106Sdes return next_state(iq, INIT_REQUEST_STATE); 2146238106Sdes } else if(type == RESPONSE_TYPE_LAME) { 2147238106Sdes /* Cache the LAMEness. */ 2148238106Sdes verbose(VERB_DETAIL, "query response was %sLAME", 2149238106Sdes dnsseclame?"DNSSEC ":""); 2150238106Sdes if(!dname_subdomain_c(iq->qchase.qname, iq->dp->name)) { 2151238106Sdes log_err("mark lame: mismatch in qname and dpname"); 2152238106Sdes /* throwaway this reply below */ 2153238106Sdes } else if(qstate->reply) { 2154238106Sdes /* need addr for lameness cache, but we may have 2155238106Sdes * gotten this from cache, so test to be sure */ 2156238106Sdes if(!infra_set_lame(qstate->env->infra_cache, 2157238106Sdes &qstate->reply->addr, qstate->reply->addrlen, 2158238106Sdes iq->dp->name, iq->dp->namelen, 2159238106Sdes *qstate->env->now, dnsseclame, 0, 2160238106Sdes iq->qchase.qtype)) 2161238106Sdes log_err("mark host lame: out of memory"); 2162238106Sdes } else log_err("%slame response from cache", 2163238106Sdes dnsseclame?"DNSSEC ":""); 2164238106Sdes } else if(type == RESPONSE_TYPE_REC_LAME) { 2165238106Sdes /* Cache the LAMEness. */ 2166238106Sdes verbose(VERB_DETAIL, "query response REC_LAME: " 2167238106Sdes "recursive but not authoritative server"); 2168238106Sdes if(!dname_subdomain_c(iq->qchase.qname, iq->dp->name)) { 2169238106Sdes log_err("mark rec_lame: mismatch in qname and dpname"); 2170238106Sdes /* throwaway this reply below */ 2171238106Sdes } else if(qstate->reply) { 2172238106Sdes /* need addr for lameness cache, but we may have 2173238106Sdes * gotten this from cache, so test to be sure */ 2174238106Sdes verbose(VERB_DETAIL, "mark as REC_LAME"); 2175238106Sdes if(!infra_set_lame(qstate->env->infra_cache, 2176238106Sdes &qstate->reply->addr, qstate->reply->addrlen, 2177238106Sdes iq->dp->name, iq->dp->namelen, 2178238106Sdes *qstate->env->now, 0, 1, iq->qchase.qtype)) 2179238106Sdes log_err("mark host lame: out of memory"); 2180238106Sdes } 2181238106Sdes } else if(type == RESPONSE_TYPE_THROWAWAY) { 2182238106Sdes /* LAME and THROWAWAY responses are handled the same way. 2183238106Sdes * In this case, the event is just sent directly back to 2184238106Sdes * the QUERYTARGETS_STATE without resetting anything, 2185238106Sdes * because, clearly, the next target must be tried. */ 2186238106Sdes verbose(VERB_DETAIL, "query response was THROWAWAY"); 2187238106Sdes } else { 2188238106Sdes log_warn("A query response came back with an unknown type: %d", 2189238106Sdes (int)type); 2190238106Sdes } 2191238106Sdes 2192238106Sdes /* LAME, THROWAWAY and "unknown" all end up here. 2193238106Sdes * Recycle to the QUERYTARGETS state to hopefully try a 2194238106Sdes * different target. */ 2195238106Sdes return next_state(iq, QUERYTARGETS_STATE); 2196238106Sdes} 2197238106Sdes 2198238106Sdes/** 2199238106Sdes * Return priming query results to interestes super querystates. 2200238106Sdes * 2201238106Sdes * Sets the delegation point and delegation message (not nonRD queries). 2202238106Sdes * This is a callback from walk_supers. 2203238106Sdes * 2204238106Sdes * @param qstate: priming query state that finished. 2205238106Sdes * @param id: module id. 2206238106Sdes * @param forq: the qstate for which priming has been done. 2207238106Sdes */ 2208238106Sdesstatic void 2209238106Sdesprime_supers(struct module_qstate* qstate, int id, struct module_qstate* forq) 2210238106Sdes{ 2211238106Sdes struct iter_qstate* foriq = (struct iter_qstate*)forq->minfo[id]; 2212238106Sdes struct delegpt* dp = NULL; 2213238106Sdes 2214238106Sdes log_assert(qstate->is_priming || foriq->wait_priming_stub); 2215238106Sdes log_assert(qstate->return_rcode == LDNS_RCODE_NOERROR); 2216238106Sdes /* Convert our response to a delegation point */ 2217238106Sdes dp = delegpt_from_message(qstate->return_msg, forq->region); 2218238106Sdes if(!dp) { 2219238106Sdes /* if there is no convertable delegation point, then 2220238106Sdes * the ANSWER type was (presumably) a negative answer. */ 2221238106Sdes verbose(VERB_ALGO, "prime response was not a positive " 2222238106Sdes "ANSWER; failing"); 2223238106Sdes foriq->dp = NULL; 2224238106Sdes foriq->state = QUERYTARGETS_STATE; 2225238106Sdes return; 2226238106Sdes } 2227238106Sdes 2228238106Sdes log_query_info(VERB_DETAIL, "priming successful for", &qstate->qinfo); 2229238106Sdes delegpt_log(VERB_ALGO, dp); 2230238106Sdes foriq->dp = dp; 2231238106Sdes foriq->deleg_msg = dns_copy_msg(qstate->return_msg, forq->region); 2232238106Sdes if(!foriq->deleg_msg) { 2233238106Sdes log_err("copy prime response: out of memory"); 2234238106Sdes foriq->dp = NULL; 2235238106Sdes foriq->state = QUERYTARGETS_STATE; 2236238106Sdes return; 2237238106Sdes } 2238238106Sdes 2239238106Sdes /* root priming responses go to init stage 2, priming stub 2240238106Sdes * responses to to stage 3. */ 2241238106Sdes if(foriq->wait_priming_stub) { 2242238106Sdes foriq->state = INIT_REQUEST_3_STATE; 2243238106Sdes foriq->wait_priming_stub = 0; 2244238106Sdes } else foriq->state = INIT_REQUEST_2_STATE; 2245238106Sdes /* because we are finished, the parent will be reactivated */ 2246238106Sdes} 2247238106Sdes 2248238106Sdes/** 2249238106Sdes * This handles the response to a priming query. This is used to handle both 2250238106Sdes * root and stub priming responses. This is basically the equivalent of the 2251238106Sdes * QUERY_RESP_STATE, but will not handle CNAME responses and will treat 2252238106Sdes * REFERRALs as ANSWERS. It will also update and reactivate the originating 2253238106Sdes * event. 2254238106Sdes * 2255238106Sdes * @param qstate: query state. 2256238106Sdes * @param id: module id. 2257238106Sdes * @return true if the event needs more immediate processing, false if not. 2258238106Sdes * This state always returns false. 2259238106Sdes */ 2260238106Sdesstatic int 2261238106SdesprocessPrimeResponse(struct module_qstate* qstate, int id) 2262238106Sdes{ 2263238106Sdes struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id]; 2264238106Sdes enum response_type type; 2265238106Sdes iq->response->rep->flags &= ~(BIT_RD|BIT_RA); /* ignore rec-lame */ 2266238106Sdes type = response_type_from_server( 2267238106Sdes (int)((iq->chase_flags&BIT_RD) || iq->chase_to_rd), 2268238106Sdes iq->response, &iq->qchase, iq->dp); 2269238106Sdes if(type == RESPONSE_TYPE_ANSWER) { 2270238106Sdes qstate->return_rcode = LDNS_RCODE_NOERROR; 2271238106Sdes qstate->return_msg = iq->response; 2272238106Sdes } else { 2273238106Sdes qstate->return_rcode = LDNS_RCODE_SERVFAIL; 2274238106Sdes qstate->return_msg = NULL; 2275238106Sdes } 2276238106Sdes 2277238106Sdes /* validate the root or stub after priming (if enabled). 2278238106Sdes * This is the same query as the prime query, but with validation. 2279238106Sdes * Now that we are primed, the additional queries that validation 2280238106Sdes * may need can be resolved, such as DLV. */ 2281238106Sdes if(qstate->env->cfg->harden_referral_path) { 2282238106Sdes struct module_qstate* subq = NULL; 2283238106Sdes log_nametypeclass(VERB_ALGO, "schedule prime validation", 2284238106Sdes qstate->qinfo.qname, qstate->qinfo.qtype, 2285238106Sdes qstate->qinfo.qclass); 2286238106Sdes if(!generate_sub_request(qstate->qinfo.qname, 2287238106Sdes qstate->qinfo.qname_len, qstate->qinfo.qtype, 2288238106Sdes qstate->qinfo.qclass, qstate, id, iq, 2289238106Sdes INIT_REQUEST_STATE, FINISHED_STATE, &subq, 1)) { 2290238106Sdes verbose(VERB_ALGO, "could not generate prime check"); 2291238106Sdes } 2292238106Sdes generate_a_aaaa_check(qstate, iq, id); 2293238106Sdes } 2294238106Sdes 2295238106Sdes /* This event is finished. */ 2296238106Sdes qstate->ext_state[id] = module_finished; 2297238106Sdes return 0; 2298238106Sdes} 2299238106Sdes 2300238106Sdes/** 2301238106Sdes * Do final processing on responses to target queries. Events reach this 2302238106Sdes * state after the iterative resolution algorithm terminates. This state is 2303238106Sdes * responsible for reactiving the original event, and housekeeping related 2304238106Sdes * to received target responses (caching, updating the current delegation 2305238106Sdes * point, etc). 2306238106Sdes * Callback from walk_supers for every super state that is interested in 2307238106Sdes * the results from this query. 2308238106Sdes * 2309238106Sdes * @param qstate: query state. 2310238106Sdes * @param id: module id. 2311238106Sdes * @param forq: super query state. 2312238106Sdes */ 2313238106Sdesstatic void 2314238106SdesprocessTargetResponse(struct module_qstate* qstate, int id, 2315238106Sdes struct module_qstate* forq) 2316238106Sdes{ 2317238106Sdes struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id]; 2318238106Sdes struct iter_qstate* foriq = (struct iter_qstate*)forq->minfo[id]; 2319238106Sdes struct ub_packed_rrset_key* rrset; 2320238106Sdes struct delegpt_ns* dpns; 2321238106Sdes log_assert(qstate->return_rcode == LDNS_RCODE_NOERROR); 2322238106Sdes 2323238106Sdes foriq->state = QUERYTARGETS_STATE; 2324238106Sdes log_query_info(VERB_ALGO, "processTargetResponse", &qstate->qinfo); 2325238106Sdes log_query_info(VERB_ALGO, "processTargetResponse super", &forq->qinfo); 2326238106Sdes 2327238106Sdes /* check to see if parent event is still interested (in orig name). */ 2328238106Sdes if(!foriq->dp) { 2329238106Sdes verbose(VERB_ALGO, "subq: parent not interested, was reset"); 2330238106Sdes return; /* not interested anymore */ 2331238106Sdes } 2332238106Sdes dpns = delegpt_find_ns(foriq->dp, qstate->qinfo.qname, 2333238106Sdes qstate->qinfo.qname_len); 2334238106Sdes if(!dpns) { 2335238106Sdes /* If not interested, just stop processing this event */ 2336238106Sdes verbose(VERB_ALGO, "subq: parent not interested anymore"); 2337238106Sdes /* could be because parent was jostled out of the cache, 2338238106Sdes and a new identical query arrived, that does not want it*/ 2339238106Sdes return; 2340238106Sdes } 2341238106Sdes 2342238106Sdes /* Tell the originating event that this target query has finished 2343238106Sdes * (regardless if it succeeded or not). */ 2344238106Sdes foriq->num_target_queries--; 2345238106Sdes 2346238106Sdes /* if iq->query_for_pside_glue then add the pside_glue (marked lame) */ 2347238106Sdes if(iq->pside_glue) { 2348238106Sdes /* if the pside_glue is NULL, then it could not be found, 2349238106Sdes * the done_pside is already set when created and a cache 2350238106Sdes * entry created in processFinished so nothing to do here */ 2351238106Sdes log_rrset_key(VERB_ALGO, "add parentside glue to dp", 2352238106Sdes iq->pside_glue); 2353238106Sdes if(!delegpt_add_rrset(foriq->dp, forq->region, 2354238106Sdes iq->pside_glue, 1)) 2355238106Sdes log_err("out of memory adding pside glue"); 2356238106Sdes } 2357238106Sdes 2358238106Sdes /* This response is relevant to the current query, so we 2359238106Sdes * add (attempt to add, anyway) this target(s) and reactivate 2360238106Sdes * the original event. 2361238106Sdes * NOTE: we could only look for the AnswerRRset if the 2362238106Sdes * response type was ANSWER. */ 2363238106Sdes rrset = reply_find_answer_rrset(&iq->qchase, qstate->return_msg->rep); 2364238106Sdes if(rrset) { 2365238106Sdes /* if CNAMEs have been followed - add new NS to delegpt. */ 2366238106Sdes /* BTW. RFC 1918 says NS should not have got CNAMEs. Robust. */ 2367238106Sdes if(!delegpt_find_ns(foriq->dp, rrset->rk.dname, 2368238106Sdes rrset->rk.dname_len)) { 2369238106Sdes /* if dpns->lame then set newcname ns lame too */ 2370238106Sdes if(!delegpt_add_ns(foriq->dp, forq->region, 2371238106Sdes rrset->rk.dname, (int)dpns->lame)) 2372238106Sdes log_err("out of memory adding cnamed-ns"); 2373238106Sdes } 2374238106Sdes /* if dpns->lame then set the address(es) lame too */ 2375238106Sdes if(!delegpt_add_rrset(foriq->dp, forq->region, rrset, 2376238106Sdes (int)dpns->lame)) 2377238106Sdes log_err("out of memory adding targets"); 2378238106Sdes verbose(VERB_ALGO, "added target response"); 2379238106Sdes delegpt_log(VERB_ALGO, foriq->dp); 2380238106Sdes } else { 2381238106Sdes verbose(VERB_ALGO, "iterator TargetResponse failed"); 2382238106Sdes dpns->resolved = 1; /* fail the target */ 2383238106Sdes } 2384238106Sdes} 2385238106Sdes 2386238106Sdes/** 2387238106Sdes * Process response for DS NS Find queries, that attempt to find the delegation 2388238106Sdes * point where we ask the DS query from. 2389238106Sdes * 2390238106Sdes * @param qstate: query state. 2391238106Sdes * @param id: module id. 2392238106Sdes * @param forq: super query state. 2393238106Sdes */ 2394238106Sdesstatic void 2395238106SdesprocessDSNSResponse(struct module_qstate* qstate, int id, 2396238106Sdes struct module_qstate* forq) 2397238106Sdes{ 2398238106Sdes struct iter_qstate* foriq = (struct iter_qstate*)forq->minfo[id]; 2399238106Sdes 2400238106Sdes /* if the finished (iq->response) query has no NS set: continue 2401238106Sdes * up to look for the right dp; nothing to change, do DPNSstate */ 2402238106Sdes if(qstate->return_rcode != LDNS_RCODE_NOERROR) 2403238106Sdes return; /* seek further */ 2404238106Sdes /* find the NS RRset (without allowing CNAMEs) */ 2405238106Sdes if(!reply_find_rrset(qstate->return_msg->rep, qstate->qinfo.qname, 2406238106Sdes qstate->qinfo.qname_len, LDNS_RR_TYPE_NS, 2407238106Sdes qstate->qinfo.qclass)){ 2408238106Sdes return; /* seek further */ 2409238106Sdes } 2410238106Sdes 2411238106Sdes /* else, store as DP and continue at querytargets */ 2412238106Sdes foriq->state = QUERYTARGETS_STATE; 2413238106Sdes foriq->dp = delegpt_from_message(qstate->return_msg, forq->region); 2414238106Sdes if(!foriq->dp) { 2415238106Sdes log_err("out of memory in dsns dp alloc"); 2416238106Sdes return; /* dp==NULL in QUERYTARGETS makes SERVFAIL */ 2417238106Sdes } 2418238106Sdes /* success, go query the querytargets in the new dp (and go down) */ 2419238106Sdes} 2420238106Sdes 2421238106Sdes/** 2422238106Sdes * Process response for qclass=ANY queries for a particular class. 2423238106Sdes * Append to result or error-exit. 2424238106Sdes * 2425238106Sdes * @param qstate: query state. 2426238106Sdes * @param id: module id. 2427238106Sdes * @param forq: super query state. 2428238106Sdes */ 2429238106Sdesstatic void 2430238106SdesprocessClassResponse(struct module_qstate* qstate, int id, 2431238106Sdes struct module_qstate* forq) 2432238106Sdes{ 2433238106Sdes struct iter_qstate* foriq = (struct iter_qstate*)forq->minfo[id]; 2434238106Sdes struct dns_msg* from = qstate->return_msg; 2435238106Sdes log_query_info(VERB_ALGO, "processClassResponse", &qstate->qinfo); 2436238106Sdes log_query_info(VERB_ALGO, "processClassResponse super", &forq->qinfo); 2437238106Sdes if(qstate->return_rcode != LDNS_RCODE_NOERROR) { 2438238106Sdes /* cause servfail for qclass ANY query */ 2439238106Sdes foriq->response = NULL; 2440238106Sdes foriq->state = FINISHED_STATE; 2441238106Sdes return; 2442238106Sdes } 2443238106Sdes /* append result */ 2444238106Sdes if(!foriq->response) { 2445238106Sdes /* allocate the response: copy RCODE, sec_state */ 2446238106Sdes foriq->response = dns_copy_msg(from, forq->region); 2447238106Sdes if(!foriq->response) { 2448238106Sdes log_err("malloc failed for qclass ANY response"); 2449238106Sdes foriq->state = FINISHED_STATE; 2450238106Sdes return; 2451238106Sdes } 2452238106Sdes foriq->response->qinfo.qclass = forq->qinfo.qclass; 2453238106Sdes /* qclass ANY does not receive the AA flag on replies */ 2454238106Sdes foriq->response->rep->authoritative = 0; 2455238106Sdes } else { 2456238106Sdes struct dns_msg* to = foriq->response; 2457238106Sdes /* add _from_ this response _to_ existing collection */ 2458238106Sdes /* if there are records, copy RCODE */ 2459238106Sdes /* lower sec_state if this message is lower */ 2460238106Sdes if(from->rep->rrset_count != 0) { 2461238106Sdes size_t n = from->rep->rrset_count+to->rep->rrset_count; 2462238106Sdes struct ub_packed_rrset_key** dest, **d; 2463238106Sdes /* copy appropriate rcode */ 2464238106Sdes to->rep->flags = from->rep->flags; 2465238106Sdes /* copy rrsets */ 2466238106Sdes dest = regional_alloc(forq->region, sizeof(dest[0])*n); 2467238106Sdes if(!dest) { 2468238106Sdes log_err("malloc failed in collect ANY"); 2469238106Sdes foriq->state = FINISHED_STATE; 2470238106Sdes return; 2471238106Sdes } 2472238106Sdes d = dest; 2473238106Sdes /* copy AN */ 2474238106Sdes memcpy(dest, to->rep->rrsets, to->rep->an_numrrsets 2475238106Sdes * sizeof(dest[0])); 2476238106Sdes dest += to->rep->an_numrrsets; 2477238106Sdes memcpy(dest, from->rep->rrsets, from->rep->an_numrrsets 2478238106Sdes * sizeof(dest[0])); 2479238106Sdes dest += from->rep->an_numrrsets; 2480238106Sdes /* copy NS */ 2481238106Sdes memcpy(dest, to->rep->rrsets+to->rep->an_numrrsets, 2482238106Sdes to->rep->ns_numrrsets * sizeof(dest[0])); 2483238106Sdes dest += to->rep->ns_numrrsets; 2484238106Sdes memcpy(dest, from->rep->rrsets+from->rep->an_numrrsets, 2485238106Sdes from->rep->ns_numrrsets * sizeof(dest[0])); 2486238106Sdes dest += from->rep->ns_numrrsets; 2487238106Sdes /* copy AR */ 2488238106Sdes memcpy(dest, to->rep->rrsets+to->rep->an_numrrsets+ 2489238106Sdes to->rep->ns_numrrsets, 2490238106Sdes to->rep->ar_numrrsets * sizeof(dest[0])); 2491238106Sdes dest += to->rep->ar_numrrsets; 2492238106Sdes memcpy(dest, from->rep->rrsets+from->rep->an_numrrsets+ 2493238106Sdes from->rep->ns_numrrsets, 2494238106Sdes from->rep->ar_numrrsets * sizeof(dest[0])); 2495238106Sdes /* update counts */ 2496238106Sdes to->rep->rrsets = d; 2497238106Sdes to->rep->an_numrrsets += from->rep->an_numrrsets; 2498238106Sdes to->rep->ns_numrrsets += from->rep->ns_numrrsets; 2499238106Sdes to->rep->ar_numrrsets += from->rep->ar_numrrsets; 2500238106Sdes to->rep->rrset_count = n; 2501238106Sdes } 2502238106Sdes if(from->rep->security < to->rep->security) /* lowest sec */ 2503238106Sdes to->rep->security = from->rep->security; 2504238106Sdes if(from->rep->qdcount != 0) /* insert qd if appropriate */ 2505238106Sdes to->rep->qdcount = from->rep->qdcount; 2506238106Sdes if(from->rep->ttl < to->rep->ttl) /* use smallest TTL */ 2507238106Sdes to->rep->ttl = from->rep->ttl; 2508238106Sdes if(from->rep->prefetch_ttl < to->rep->prefetch_ttl) 2509238106Sdes to->rep->prefetch_ttl = from->rep->prefetch_ttl; 2510238106Sdes } 2511238106Sdes /* are we done? */ 2512238106Sdes foriq->num_current_queries --; 2513238106Sdes if(foriq->num_current_queries == 0) 2514238106Sdes foriq->state = FINISHED_STATE; 2515238106Sdes} 2516238106Sdes 2517238106Sdes/** 2518238106Sdes * Collect class ANY responses and make them into one response. This 2519238106Sdes * state is started and it creates queries for all classes (that have 2520238106Sdes * root hints). The answers are then collected. 2521238106Sdes * 2522238106Sdes * @param qstate: query state. 2523238106Sdes * @param id: module id. 2524238106Sdes * @return true if the event needs more immediate processing, false if not. 2525238106Sdes */ 2526238106Sdesstatic int 2527238106SdesprocessCollectClass(struct module_qstate* qstate, int id) 2528238106Sdes{ 2529238106Sdes struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id]; 2530238106Sdes struct module_qstate* subq; 2531238106Sdes /* If qchase.qclass == 0 then send out queries for all classes. 2532238106Sdes * Otherwise, do nothing (wait for all answers to arrive and the 2533238106Sdes * processClassResponse to put them together, and that moves us 2534238106Sdes * towards the Finished state when done. */ 2535238106Sdes if(iq->qchase.qclass == 0) { 2536238106Sdes uint16_t c = 0; 2537238106Sdes iq->qchase.qclass = LDNS_RR_CLASS_ANY; 2538238106Sdes while(iter_get_next_root(qstate->env->hints, 2539238106Sdes qstate->env->fwds, &c)) { 2540238106Sdes /* generate query for this class */ 2541238106Sdes log_nametypeclass(VERB_ALGO, "spawn collect query", 2542238106Sdes qstate->qinfo.qname, qstate->qinfo.qtype, c); 2543238106Sdes if(!generate_sub_request(qstate->qinfo.qname, 2544238106Sdes qstate->qinfo.qname_len, qstate->qinfo.qtype, 2545238106Sdes c, qstate, id, iq, INIT_REQUEST_STATE, 2546238106Sdes FINISHED_STATE, &subq, 2547238106Sdes (int)!(qstate->query_flags&BIT_CD))) { 2548238106Sdes return error_response(qstate, id, 2549238106Sdes LDNS_RCODE_SERVFAIL); 2550238106Sdes } 2551238106Sdes /* ignore subq, no special init required */ 2552238106Sdes iq->num_current_queries ++; 2553238106Sdes if(c == 0xffff) 2554238106Sdes break; 2555238106Sdes else c++; 2556238106Sdes } 2557238106Sdes /* if no roots are configured at all, return */ 2558238106Sdes if(iq->num_current_queries == 0) { 2559238106Sdes verbose(VERB_ALGO, "No root hints or fwds, giving up " 2560238106Sdes "on qclass ANY"); 2561238106Sdes return error_response(qstate, id, LDNS_RCODE_REFUSED); 2562238106Sdes } 2563238106Sdes /* return false, wait for queries to return */ 2564238106Sdes } 2565238106Sdes /* if woke up here because of an answer, wait for more answers */ 2566238106Sdes return 0; 2567238106Sdes} 2568238106Sdes 2569238106Sdes/** 2570238106Sdes * This handles the final state for first-tier responses (i.e., responses to 2571238106Sdes * externally generated queries). 2572238106Sdes * 2573238106Sdes * @param qstate: query state. 2574238106Sdes * @param iq: iterator query state. 2575238106Sdes * @param id: module id. 2576238106Sdes * @return true if the event needs more processing, false if not. Since this 2577238106Sdes * is the final state for an event, it always returns false. 2578238106Sdes */ 2579238106Sdesstatic int 2580238106SdesprocessFinished(struct module_qstate* qstate, struct iter_qstate* iq, 2581238106Sdes int id) 2582238106Sdes{ 2583238106Sdes log_query_info(VERB_QUERY, "finishing processing for", 2584238106Sdes &qstate->qinfo); 2585238106Sdes 2586238106Sdes /* store negative cache element for parent side glue. */ 2587238106Sdes if(iq->query_for_pside_glue && !iq->pside_glue) 2588238106Sdes iter_store_parentside_neg(qstate->env, &qstate->qinfo, 2589238106Sdes iq->deleg_msg?iq->deleg_msg->rep: 2590238106Sdes (iq->response?iq->response->rep:NULL)); 2591238106Sdes if(!iq->response) { 2592238106Sdes verbose(VERB_ALGO, "No response is set, servfail"); 2593238106Sdes return error_response(qstate, id, LDNS_RCODE_SERVFAIL); 2594238106Sdes } 2595238106Sdes 2596238106Sdes /* Make sure that the RA flag is set (since the presence of 2597238106Sdes * this module means that recursion is available) */ 2598238106Sdes iq->response->rep->flags |= BIT_RA; 2599238106Sdes 2600238106Sdes /* Clear the AA flag */ 2601238106Sdes /* FIXME: does this action go here or in some other module? */ 2602238106Sdes iq->response->rep->flags &= ~BIT_AA; 2603238106Sdes 2604238106Sdes /* make sure QR flag is on */ 2605238106Sdes iq->response->rep->flags |= BIT_QR; 2606238106Sdes 2607238106Sdes /* we have finished processing this query */ 2608238106Sdes qstate->ext_state[id] = module_finished; 2609238106Sdes 2610238106Sdes /* TODO: we are using a private TTL, trim the response. */ 2611238106Sdes /* if (mPrivateTTL > 0){IterUtils.setPrivateTTL(resp, mPrivateTTL); } */ 2612238106Sdes 2613238106Sdes /* prepend any items we have accumulated */ 2614238106Sdes if(iq->an_prepend_list || iq->ns_prepend_list) { 2615238106Sdes if(!iter_prepend(iq, iq->response, qstate->region)) { 2616238106Sdes log_err("prepend rrsets: out of memory"); 2617238106Sdes return error_response(qstate, id, LDNS_RCODE_SERVFAIL); 2618238106Sdes } 2619238106Sdes /* reset the query name back */ 2620238106Sdes iq->response->qinfo = qstate->qinfo; 2621238106Sdes /* the security state depends on the combination */ 2622238106Sdes iq->response->rep->security = sec_status_unchecked; 2623238106Sdes /* store message with the finished prepended items, 2624238106Sdes * but only if we did recursion. The nonrecursion referral 2625238106Sdes * from cache does not need to be stored in the msg cache. */ 2626238106Sdes if(qstate->query_flags&BIT_RD) { 2627249141Sdes iter_dns_store(qstate->env, &qstate->qinfo, 2628238106Sdes iq->response->rep, 0, qstate->prefetch_leeway, 2629238106Sdes iq->dp&&iq->dp->has_parent_side_NS, 2630249141Sdes qstate->region); 2631238106Sdes } 2632238106Sdes } 2633238106Sdes qstate->return_rcode = LDNS_RCODE_NOERROR; 2634238106Sdes qstate->return_msg = iq->response; 2635238106Sdes return 0; 2636238106Sdes} 2637238106Sdes 2638238106Sdes/* 2639238106Sdes * Return priming query results to interestes super querystates. 2640238106Sdes * 2641238106Sdes * Sets the delegation point and delegation message (not nonRD queries). 2642238106Sdes * This is a callback from walk_supers. 2643238106Sdes * 2644238106Sdes * @param qstate: query state that finished. 2645238106Sdes * @param id: module id. 2646238106Sdes * @param super: the qstate to inform. 2647238106Sdes */ 2648238106Sdesvoid 2649238106Sdesiter_inform_super(struct module_qstate* qstate, int id, 2650238106Sdes struct module_qstate* super) 2651238106Sdes{ 2652238106Sdes if(!qstate->is_priming && super->qinfo.qclass == LDNS_RR_CLASS_ANY) 2653238106Sdes processClassResponse(qstate, id, super); 2654238106Sdes else if(super->qinfo.qtype == LDNS_RR_TYPE_DS && ((struct iter_qstate*) 2655238106Sdes super->minfo[id])->state == DSNS_FIND_STATE) 2656238106Sdes processDSNSResponse(qstate, id, super); 2657238106Sdes else if(qstate->return_rcode != LDNS_RCODE_NOERROR) 2658238106Sdes error_supers(qstate, id, super); 2659238106Sdes else if(qstate->is_priming) 2660238106Sdes prime_supers(qstate, id, super); 2661238106Sdes else processTargetResponse(qstate, id, super); 2662238106Sdes} 2663238106Sdes 2664238106Sdes/** 2665238106Sdes * Handle iterator state. 2666238106Sdes * Handle events. This is the real processing loop for events, responsible 2667238106Sdes * for moving events through the various states. If a processing method 2668238106Sdes * returns true, then it will be advanced to the next state. If false, then 2669238106Sdes * processing will stop. 2670238106Sdes * 2671238106Sdes * @param qstate: query state. 2672238106Sdes * @param ie: iterator shared global environment. 2673238106Sdes * @param iq: iterator query state. 2674238106Sdes * @param id: module id. 2675238106Sdes */ 2676238106Sdesstatic void 2677238106Sdesiter_handle(struct module_qstate* qstate, struct iter_qstate* iq, 2678238106Sdes struct iter_env* ie, int id) 2679238106Sdes{ 2680238106Sdes int cont = 1; 2681238106Sdes while(cont) { 2682238106Sdes verbose(VERB_ALGO, "iter_handle processing q with state %s", 2683238106Sdes iter_state_to_string(iq->state)); 2684238106Sdes switch(iq->state) { 2685238106Sdes case INIT_REQUEST_STATE: 2686238106Sdes cont = processInitRequest(qstate, iq, ie, id); 2687238106Sdes break; 2688238106Sdes case INIT_REQUEST_2_STATE: 2689238106Sdes cont = processInitRequest2(qstate, iq, id); 2690238106Sdes break; 2691238106Sdes case INIT_REQUEST_3_STATE: 2692238106Sdes cont = processInitRequest3(qstate, iq, id); 2693238106Sdes break; 2694238106Sdes case QUERYTARGETS_STATE: 2695238106Sdes cont = processQueryTargets(qstate, iq, ie, id); 2696238106Sdes break; 2697238106Sdes case QUERY_RESP_STATE: 2698238106Sdes cont = processQueryResponse(qstate, iq, id); 2699238106Sdes break; 2700238106Sdes case PRIME_RESP_STATE: 2701238106Sdes cont = processPrimeResponse(qstate, id); 2702238106Sdes break; 2703238106Sdes case COLLECT_CLASS_STATE: 2704238106Sdes cont = processCollectClass(qstate, id); 2705238106Sdes break; 2706238106Sdes case DSNS_FIND_STATE: 2707238106Sdes cont = processDSNSFind(qstate, iq, id); 2708238106Sdes break; 2709238106Sdes case FINISHED_STATE: 2710238106Sdes cont = processFinished(qstate, iq, id); 2711238106Sdes break; 2712238106Sdes default: 2713238106Sdes log_warn("iterator: invalid state: %d", 2714238106Sdes iq->state); 2715238106Sdes cont = 0; 2716238106Sdes break; 2717238106Sdes } 2718238106Sdes } 2719238106Sdes} 2720238106Sdes 2721238106Sdes/** 2722238106Sdes * This is the primary entry point for processing request events. Note that 2723238106Sdes * this method should only be used by external modules. 2724238106Sdes * @param qstate: query state. 2725238106Sdes * @param ie: iterator shared global environment. 2726238106Sdes * @param iq: iterator query state. 2727238106Sdes * @param id: module id. 2728238106Sdes */ 2729238106Sdesstatic void 2730238106Sdesprocess_request(struct module_qstate* qstate, struct iter_qstate* iq, 2731238106Sdes struct iter_env* ie, int id) 2732238106Sdes{ 2733238106Sdes /* external requests start in the INIT state, and finish using the 2734238106Sdes * FINISHED state. */ 2735238106Sdes iq->state = INIT_REQUEST_STATE; 2736238106Sdes iq->final_state = FINISHED_STATE; 2737238106Sdes verbose(VERB_ALGO, "process_request: new external request event"); 2738238106Sdes iter_handle(qstate, iq, ie, id); 2739238106Sdes} 2740238106Sdes 2741238106Sdes/** process authoritative server reply */ 2742238106Sdesstatic void 2743238106Sdesprocess_response(struct module_qstate* qstate, struct iter_qstate* iq, 2744238106Sdes struct iter_env* ie, int id, struct outbound_entry* outbound, 2745238106Sdes enum module_ev event) 2746238106Sdes{ 2747238106Sdes struct msg_parse* prs; 2748238106Sdes struct edns_data edns; 2749238106Sdes ldns_buffer* pkt; 2750238106Sdes 2751238106Sdes verbose(VERB_ALGO, "process_response: new external response event"); 2752238106Sdes iq->response = NULL; 2753238106Sdes iq->state = QUERY_RESP_STATE; 2754238106Sdes if(event == module_event_noreply || event == module_event_error) { 2755238106Sdes goto handle_it; 2756238106Sdes } 2757238106Sdes if( (event != module_event_reply && event != module_event_capsfail) 2758238106Sdes || !qstate->reply) { 2759238106Sdes log_err("Bad event combined with response"); 2760238106Sdes outbound_list_remove(&iq->outlist, outbound); 2761238106Sdes (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL); 2762238106Sdes return; 2763238106Sdes } 2764238106Sdes 2765238106Sdes /* parse message */ 2766238106Sdes prs = (struct msg_parse*)regional_alloc(qstate->env->scratch, 2767238106Sdes sizeof(struct msg_parse)); 2768238106Sdes if(!prs) { 2769238106Sdes log_err("out of memory on incoming message"); 2770238106Sdes /* like packet got dropped */ 2771238106Sdes goto handle_it; 2772238106Sdes } 2773238106Sdes memset(prs, 0, sizeof(*prs)); 2774238106Sdes memset(&edns, 0, sizeof(edns)); 2775238106Sdes pkt = qstate->reply->c->buffer; 2776238106Sdes ldns_buffer_set_position(pkt, 0); 2777238106Sdes if(parse_packet(pkt, prs, qstate->env->scratch) != LDNS_RCODE_NOERROR) { 2778238106Sdes verbose(VERB_ALGO, "parse error on reply packet"); 2779238106Sdes goto handle_it; 2780238106Sdes } 2781238106Sdes /* edns is not examined, but removed from message to help cache */ 2782238106Sdes if(parse_extract_edns(prs, &edns) != LDNS_RCODE_NOERROR) 2783238106Sdes goto handle_it; 2784238106Sdes /* remove CD-bit, we asked for in case we handle validation ourself */ 2785238106Sdes prs->flags &= ~BIT_CD; 2786238106Sdes 2787238106Sdes /* normalize and sanitize: easy to delete items from linked lists */ 2788238106Sdes if(!scrub_message(pkt, prs, &iq->qchase, iq->dp->name, 2789238106Sdes qstate->env->scratch, qstate->env, ie)) 2790238106Sdes goto handle_it; 2791238106Sdes 2792238106Sdes /* allocate response dns_msg in region */ 2793238106Sdes iq->response = dns_alloc_msg(pkt, prs, qstate->region); 2794238106Sdes if(!iq->response) 2795238106Sdes goto handle_it; 2796238106Sdes log_query_info(VERB_DETAIL, "response for", &qstate->qinfo); 2797238106Sdes log_name_addr(VERB_DETAIL, "reply from", iq->dp->name, 2798238106Sdes &qstate->reply->addr, qstate->reply->addrlen); 2799238106Sdes if(verbosity >= VERB_ALGO) 2800238106Sdes log_dns_msg("incoming scrubbed packet:", &iq->response->qinfo, 2801238106Sdes iq->response->rep); 2802238106Sdes 2803238106Sdes if(event == module_event_capsfail) { 2804238106Sdes if(!iq->caps_fallback) { 2805238106Sdes /* start fallback */ 2806238106Sdes iq->caps_fallback = 1; 2807238106Sdes iq->caps_server = 0; 2808238106Sdes iq->caps_reply = iq->response->rep; 2809238106Sdes iq->state = QUERYTARGETS_STATE; 2810238106Sdes iq->num_current_queries--; 2811238106Sdes verbose(VERB_DETAIL, "Capsforid: starting fallback"); 2812238106Sdes goto handle_it; 2813238106Sdes } else { 2814238106Sdes /* check if reply is the same, otherwise, fail */ 2815238106Sdes if(!reply_equal(iq->response->rep, iq->caps_reply, 2816238106Sdes qstate->env->scratch_buffer)) { 2817238106Sdes verbose(VERB_DETAIL, "Capsforid fallback: " 2818238106Sdes "getting different replies, failed"); 2819238106Sdes outbound_list_remove(&iq->outlist, outbound); 2820238106Sdes (void)error_response(qstate, id, 2821238106Sdes LDNS_RCODE_SERVFAIL); 2822238106Sdes return; 2823238106Sdes } 2824238106Sdes /* continue the fallback procedure at next server */ 2825238106Sdes iq->caps_server++; 2826238106Sdes iq->state = QUERYTARGETS_STATE; 2827238106Sdes iq->num_current_queries--; 2828238106Sdes verbose(VERB_DETAIL, "Capsforid: reply is equal. " 2829238106Sdes "go to next fallback"); 2830238106Sdes goto handle_it; 2831238106Sdes } 2832238106Sdes } 2833238106Sdes iq->caps_fallback = 0; /* if we were in fallback, 0x20 is OK now */ 2834238106Sdes 2835238106Sdeshandle_it: 2836238106Sdes outbound_list_remove(&iq->outlist, outbound); 2837238106Sdes iter_handle(qstate, iq, ie, id); 2838238106Sdes} 2839238106Sdes 2840238106Sdesvoid 2841238106Sdesiter_operate(struct module_qstate* qstate, enum module_ev event, int id, 2842238106Sdes struct outbound_entry* outbound) 2843238106Sdes{ 2844238106Sdes struct iter_env* ie = (struct iter_env*)qstate->env->modinfo[id]; 2845238106Sdes struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id]; 2846238106Sdes verbose(VERB_QUERY, "iterator[module %d] operate: extstate:%s event:%s", 2847238106Sdes id, strextstate(qstate->ext_state[id]), strmodulevent(event)); 2848238106Sdes if(iq) log_query_info(VERB_QUERY, "iterator operate: query", 2849238106Sdes &qstate->qinfo); 2850238106Sdes if(iq && qstate->qinfo.qname != iq->qchase.qname) 2851238106Sdes log_query_info(VERB_QUERY, "iterator operate: chased to", 2852238106Sdes &iq->qchase); 2853238106Sdes 2854238106Sdes /* perform iterator state machine */ 2855238106Sdes if((event == module_event_new || event == module_event_pass) && 2856238106Sdes iq == NULL) { 2857238106Sdes if(!iter_new(qstate, id)) { 2858238106Sdes (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL); 2859238106Sdes return; 2860238106Sdes } 2861238106Sdes iq = (struct iter_qstate*)qstate->minfo[id]; 2862238106Sdes process_request(qstate, iq, ie, id); 2863238106Sdes return; 2864238106Sdes } 2865238106Sdes if(iq && event == module_event_pass) { 2866238106Sdes iter_handle(qstate, iq, ie, id); 2867238106Sdes return; 2868238106Sdes } 2869238106Sdes if(iq && outbound) { 2870238106Sdes process_response(qstate, iq, ie, id, outbound, event); 2871238106Sdes return; 2872238106Sdes } 2873238106Sdes if(event == module_event_error) { 2874238106Sdes verbose(VERB_ALGO, "got called with event error, giving up"); 2875238106Sdes (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL); 2876238106Sdes return; 2877238106Sdes } 2878238106Sdes 2879238106Sdes log_err("bad event for iterator"); 2880238106Sdes (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL); 2881238106Sdes} 2882238106Sdes 2883238106Sdesvoid 2884238106Sdesiter_clear(struct module_qstate* qstate, int id) 2885238106Sdes{ 2886238106Sdes struct iter_qstate* iq; 2887238106Sdes if(!qstate) 2888238106Sdes return; 2889238106Sdes iq = (struct iter_qstate*)qstate->minfo[id]; 2890238106Sdes if(iq) { 2891238106Sdes outbound_list_clear(&iq->outlist); 2892275854Sdelphij if(iq->target_count && --iq->target_count[0] == 0) 2893275854Sdelphij free(iq->target_count); 2894238106Sdes iq->num_current_queries = 0; 2895238106Sdes } 2896238106Sdes qstate->minfo[id] = NULL; 2897238106Sdes} 2898238106Sdes 2899238106Sdessize_t 2900238106Sdesiter_get_mem(struct module_env* env, int id) 2901238106Sdes{ 2902238106Sdes struct iter_env* ie = (struct iter_env*)env->modinfo[id]; 2903238106Sdes if(!ie) 2904238106Sdes return 0; 2905238106Sdes return sizeof(*ie) + sizeof(int)*((size_t)ie->max_dependency_depth+1) 2906238106Sdes + donotq_get_mem(ie->donotq) + priv_get_mem(ie->priv); 2907238106Sdes} 2908238106Sdes 2909238106Sdes/** 2910238106Sdes * The iterator function block 2911238106Sdes */ 2912238106Sdesstatic struct module_func_block iter_block = { 2913238106Sdes "iterator", 2914238106Sdes &iter_init, &iter_deinit, &iter_operate, &iter_inform_super, 2915238106Sdes &iter_clear, &iter_get_mem 2916238106Sdes}; 2917238106Sdes 2918238106Sdesstruct module_func_block* 2919238106Sdesiter_get_funcblock(void) 2920238106Sdes{ 2921238106Sdes return &iter_block; 2922238106Sdes} 2923238106Sdes 2924238106Sdesconst char* 2925238106Sdesiter_state_to_string(enum iter_state state) 2926238106Sdes{ 2927238106Sdes switch (state) 2928238106Sdes { 2929238106Sdes case INIT_REQUEST_STATE : 2930238106Sdes return "INIT REQUEST STATE"; 2931238106Sdes case INIT_REQUEST_2_STATE : 2932238106Sdes return "INIT REQUEST STATE (stage 2)"; 2933238106Sdes case INIT_REQUEST_3_STATE: 2934238106Sdes return "INIT REQUEST STATE (stage 3)"; 2935238106Sdes case QUERYTARGETS_STATE : 2936238106Sdes return "QUERY TARGETS STATE"; 2937238106Sdes case PRIME_RESP_STATE : 2938238106Sdes return "PRIME RESPONSE STATE"; 2939238106Sdes case COLLECT_CLASS_STATE : 2940238106Sdes return "COLLECT CLASS STATE"; 2941238106Sdes case DSNS_FIND_STATE : 2942238106Sdes return "DSNS FIND STATE"; 2943238106Sdes case QUERY_RESP_STATE : 2944238106Sdes return "QUERY RESPONSE STATE"; 2945238106Sdes case FINISHED_STATE : 2946238106Sdes return "FINISHED RESPONSE STATE"; 2947238106Sdes default : 2948238106Sdes return "UNKNOWN ITER STATE"; 2949238106Sdes } 2950238106Sdes} 2951238106Sdes 2952238106Sdesint 2953238106Sdesiter_state_is_responsestate(enum iter_state s) 2954238106Sdes{ 2955238106Sdes switch(s) { 2956238106Sdes case INIT_REQUEST_STATE : 2957238106Sdes case INIT_REQUEST_2_STATE : 2958238106Sdes case INIT_REQUEST_3_STATE : 2959238106Sdes case QUERYTARGETS_STATE : 2960238106Sdes case COLLECT_CLASS_STATE : 2961238106Sdes return 0; 2962238106Sdes default: 2963238106Sdes break; 2964238106Sdes } 2965238106Sdes return 1; 2966238106Sdes} 2967