contrib/unbound/daemon/worker.c

   1 /*
   2  * daemon/worker.c - worker that handles a pending list of requests.
   3  *
   4  * Copyright (c) 2007, NLnet Labs. All rights reserved.
   5  *
   6  * This software is open source.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * Redistributions of source code must retain the above copyright notice,
  13  * this list of conditions and the following disclaimer.
  14  *
  15  * Redistributions in binary form must reproduce the above copyright notice,
  16  * this list of conditions and the following disclaimer in the documentation
  17  * and/or other materials provided with the distribution.
  18  *
  19  * Neither the name of the NLNET LABS nor the names of its contributors may
  20  * be used to endorse or promote products derived from this software without
  21  * specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  24  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  25  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  26  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  27  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
  29  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  30  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  31  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  32  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  33  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  34  */
  35
  36 /**
  37  * \file
  38  *
  39  * This file implements the worker that handles callbacks on events, for
  40  * pending requests.
  41  */
  42 #include "config.h"
  43 #include "util/log.h"
  44 #include "util/net_help.h"
  45 #include "util/random.h"
  46 #include "daemon/worker.h"
  47 #include "daemon/daemon.h"
  48 #include "daemon/remote.h"
  49 #include "daemon/acl_list.h"
  50 #include "util/netevent.h"
  51 #include "util/config_file.h"
  52 #include "util/module.h"
  53 #include "util/regional.h"
  54 #include "util/storage/slabhash.h"
  55 #include "services/listen_dnsport.h"
  56 #include "services/outside_network.h"
  57 #include "services/outbound_list.h"
  58 #include "services/cache/rrset.h"
  59 #include "services/cache/infra.h"
  60 #include "services/cache/dns.h"
  61 #include "services/mesh.h"
  62 #include "services/localzone.h"
  63 #include "util/data/msgparse.h"
  64 #include "util/data/msgencode.h"
  65 #include "util/data/dname.h"
  66 #include "util/fptr_wlist.h"
  67 #include "util/tube.h"
  68 #include "iterator/iter_fwd.h"
  69 #include "iterator/iter_hints.h"
  70 #include "validator/autotrust.h"
  71 #include "validator/val_anchor.h"
  72 #include "libunbound/context.h"
  73 #include "libunbound/libworker.h"
  74 #include "sldns/sbuffer.h"
  75
  76 #ifdef HAVE_SYS_TYPES_H
  77 #  include <sys/types.h>
  78 #endif
  79 #ifdef HAVE_NETDB_H
  80 #include <netdb.h>
  81 #endif
  82 #include <signal.h>
  83 #ifdef UB_ON_WINDOWS
  84 #include "winrc/win_svc.h"
  85 #endif
  86
  87 /** Size of an UDP datagram */
  88 #define NORMAL_UDP_SIZE 512 /* bytes */
  89 /** ratelimit for error responses */
  90 #define ERROR_RATELIMIT 100 /* qps */
  91
  92 /**
  93  * seconds to add to prefetch leeway.  This is a TTL that expires old rrsets
  94  * earlier than they should in order to put the new update into the cache.
  95  * This additional value is to make sure that if not all TTLs are equal in
  96  * the message to be updated(and replaced), that rrsets with up to this much
  97  * extra TTL are also replaced.  This means that the resulting new message
  98  * will have (most likely) this TTL at least, avoiding very small 'split
  99  * second' TTLs due to operators choosing relative primes for TTLs (or so).
 100  * Also has to be at least one to break ties (and overwrite cached entry).
 101  */
 102 #define PREFETCH_EXPIRY_ADD 60
 103
 104 #ifdef UNBOUND_ALLOC_STATS
 105 /** measure memory leakage */
 106 static void
 107 debug_memleak(size_t accounted, size_t heap,
 108         size_t total_alloc, size_t total_free)
 109 {
 110         static int init = 0;
 111         static size_t base_heap, base_accounted, base_alloc, base_free;
 112         size_t base_af, cur_af, grow_af, grow_acc;
 113         if(!init) {
 114                 init = 1;
 115                 base_heap = heap;
 116                 base_accounted = accounted;
 117                 base_alloc = total_alloc;
 118                 base_free = total_free;
 119         }
 120         base_af = base_alloc - base_free;
 121         cur_af = total_alloc - total_free;
 122         grow_af = cur_af - base_af;
 123         grow_acc = accounted - base_accounted;
 124         log_info("Leakage: %d leaked. growth: %u use, %u acc, %u heap",
 125                 (int)(grow_af - grow_acc), (unsigned)grow_af,
 126                 (unsigned)grow_acc, (unsigned)(heap - base_heap));
 127 }
 128
 129 /** give debug heap size indication */
 130 static void
 131 debug_total_mem(size_t calctotal)
 132 {
 133 #ifdef HAVE_SBRK
 134         extern void* unbound_start_brk;
 135         extern size_t unbound_mem_alloc, unbound_mem_freed;
 136         void* cur = sbrk(0);
 137         int total = cur-unbound_start_brk;
 138         log_info("Total heap memory estimate: %u  total-alloc: %u  "
 139                 "total-free: %u", (unsigned)total,
 140                 (unsigned)unbound_mem_alloc, (unsigned)unbound_mem_freed);
 141         debug_memleak(calctotal, (size_t)total,
 142                 unbound_mem_alloc, unbound_mem_freed);
 143 #else
 144         (void)calctotal;
 145 #endif /* HAVE_SBRK */
 146 }
 147 #endif /* UNBOUND_ALLOC_STATS */
 148
 149 /** Report on memory usage by this thread and global */
 150 static void
 151 worker_mem_report(struct worker* ATTR_UNUSED(worker),
 152         struct serviced_query* ATTR_UNUSED(cur_serv))
 153 {
 154 #ifdef UNBOUND_ALLOC_STATS
 155         /* debug func in validator module */
 156         size_t total, front, back, mesh, msg, rrset, infra, ac, superac;
 157         size_t me, iter, val, anch;
 158         int i;
 159         if(verbosity < VERB_ALGO)
 160                 return;
 161         front = listen_get_mem(worker->front);
 162         back = outnet_get_mem(worker->back);
 163         msg = slabhash_get_mem(worker->env.msg_cache);
 164         rrset = slabhash_get_mem(&worker->env.rrset_cache->table);
 165         infra = infra_get_mem(worker->env.infra_cache);
 166         mesh = mesh_get_mem(worker->env.mesh);
 167         ac = alloc_get_mem(&worker->alloc);
 168         superac = alloc_get_mem(&worker->daemon->superalloc);
 169         anch = anchors_get_mem(worker->env.anchors);
 170         iter = 0;
 171         val = 0;
 172         for(i=0; i<worker->env.mesh->mods.num; i++) {
 173                 fptr_ok(fptr_whitelist_mod_get_mem(worker->env.mesh->
 174                         mods.mod[i]->get_mem));
 175                 if(strcmp(worker->env.mesh->mods.mod[i]->name, "validator")==0)
 176                         val += (*worker->env.mesh->mods.mod[i]->get_mem)
 177                                 (&worker->env, i);
 178                 else    iter += (*worker->env.mesh->mods.mod[i]->get_mem)
 179                                 (&worker->env, i);
 180         }
 181         me = sizeof(*worker) + sizeof(*worker->base) + sizeof(*worker->comsig)
 182                 + comm_point_get_mem(worker->cmd_com)
 183                 + sizeof(worker->rndstate)
 184                 + regional_get_mem(worker->scratchpad)
 185                 + sizeof(*worker->env.scratch_buffer)
 186                 + sldns_buffer_capacity(worker->env.scratch_buffer)
 187                 + forwards_get_mem(worker->env.fwds)
 188                 + hints_get_mem(worker->env.hints);
 189         if(worker->thread_num == 0)
 190                 me += acl_list_get_mem(worker->daemon->acl);
 191         if(cur_serv) {
 192                 me += serviced_get_mem(cur_serv);
 193         }
 194         total = front+back+mesh+msg+rrset+infra+iter+val+ac+superac+me;
 195         log_info("Memory conditions: %u front=%u back=%u mesh=%u msg=%u "
 196                 "rrset=%u infra=%u iter=%u val=%u anchors=%u "
 197                 "alloccache=%u globalalloccache=%u me=%u",
 198                 (unsigned)total, (unsigned)front, (unsigned)back,
 199                 (unsigned)mesh, (unsigned)msg, (unsigned)rrset,
 200                 (unsigned)infra, (unsigned)iter, (unsigned)val, (unsigned)anch,
 201                 (unsigned)ac, (unsigned)superac, (unsigned)me);
 202         debug_total_mem(total);
 203 #else /* no UNBOUND_ALLOC_STATS */
 204         size_t val = 0;
 205         int i;
 206         if(verbosity < VERB_QUERY)
 207                 return;
 208         for(i=0; i<worker->env.mesh->mods.num; i++) {
 209                 fptr_ok(fptr_whitelist_mod_get_mem(worker->env.mesh->
 210                         mods.mod[i]->get_mem));
 211                 if(strcmp(worker->env.mesh->mods.mod[i]->name, "validator")==0)
 212                         val += (*worker->env.mesh->mods.mod[i]->get_mem)
 213                                 (&worker->env, i);
 214         }
 215         verbose(VERB_QUERY, "cache memory msg=%u rrset=%u infra=%u val=%u",
 216                 (unsigned)slabhash_get_mem(worker->env.msg_cache),
 217                 (unsigned)slabhash_get_mem(&worker->env.rrset_cache->table),
 218                 (unsigned)infra_get_mem(worker->env.infra_cache),
 219                 (unsigned)val);
 220 #endif /* UNBOUND_ALLOC_STATS */
 221 }
 222
 223 void
 224 worker_send_cmd(struct worker* worker, enum worker_commands cmd)
 225 {
 226         uint32_t c = (uint32_t)htonl(cmd);
 227         if(!tube_write_msg(worker->cmd, (uint8_t*)&c, sizeof(c), 0)) {
 228                 log_err("worker send cmd %d failed", (int)cmd);
 229         }
 230 }
 231
 232 int
 233 worker_handle_reply(struct comm_point* c, void* arg, int error,
 234         struct comm_reply* reply_info)
 235 {
 236         struct module_qstate* q = (struct module_qstate*)arg;
 237         struct worker* worker = q->env->worker;
 238         struct outbound_entry e;
 239         e.qstate = q;
 240         e.qsent = NULL;
 241
 242         if(error != 0) {
 243                 mesh_report_reply(worker->env.mesh, &e, reply_info, error);
 244                 worker_mem_report(worker, NULL);
 245                 return 0;
 246         }
 247         /* sanity check. */
 248         if(!LDNS_QR_WIRE(sldns_buffer_begin(c->buffer))
 249                 || LDNS_OPCODE_WIRE(sldns_buffer_begin(c->buffer)) !=
 250                         LDNS_PACKET_QUERY
 251                 || LDNS_QDCOUNT(sldns_buffer_begin(c->buffer)) > 1) {
 252                 /* error becomes timeout for the module as if this reply
 253                  * never arrived. */
 254                 mesh_report_reply(worker->env.mesh, &e, reply_info,
 255                         NETEVENT_TIMEOUT);
 256                 worker_mem_report(worker, NULL);
 257                 return 0;
 258         }
 259         mesh_report_reply(worker->env.mesh, &e, reply_info, NETEVENT_NOERROR);
 260         worker_mem_report(worker, NULL);
 261         return 0;
 262 }
 263
 264 int
 265 worker_handle_service_reply(struct comm_point* c, void* arg, int error,
 266         struct comm_reply* reply_info)
 267 {
 268         struct outbound_entry* e = (struct outbound_entry*)arg;
 269         struct worker* worker = e->qstate->env->worker;
 270         struct serviced_query *sq = e->qsent;
 271
 272         verbose(VERB_ALGO, "worker svcd callback for qstate %p", e->qstate);
 273         if(error != 0) {
 274                 mesh_report_reply(worker->env.mesh, e, reply_info, error);
 275                 worker_mem_report(worker, sq);
 276                 return 0;
 277         }
 278         /* sanity check. */
 279         if(!LDNS_QR_WIRE(sldns_buffer_begin(c->buffer))
 280                 || LDNS_OPCODE_WIRE(sldns_buffer_begin(c->buffer)) !=
 281                         LDNS_PACKET_QUERY
 282                 || LDNS_QDCOUNT(sldns_buffer_begin(c->buffer)) > 1) {
 283                 /* error becomes timeout for the module as if this reply
 284                  * never arrived. */
 285                 verbose(VERB_ALGO, "worker: bad reply handled as timeout");
 286                 mesh_report_reply(worker->env.mesh, e, reply_info,
 287                         NETEVENT_TIMEOUT);
 288                 worker_mem_report(worker, sq);
 289                 return 0;
 290         }
 291         mesh_report_reply(worker->env.mesh, e, reply_info, NETEVENT_NOERROR);
 292         worker_mem_report(worker, sq);
 293         return 0;
 294 }
 295
 296 /** ratelimit error replies
 297  * @param worker: the worker struct with ratelimit counter
 298  * @param err: error code that would be wanted.
 299  * @return value of err if okay, or -1 if it should be discarded instead.
 300  */
 301 static int
 302 worker_err_ratelimit(struct worker* worker, int err)
 303 {
 304         if(worker->err_limit_time == *worker->env.now) {
 305                 /* see if limit is exceeded for this second */
 306                 if(worker->err_limit_count++ > ERROR_RATELIMIT)
 307                         return -1;
 308         } else {
 309                 /* new second, new limits */
 310                 worker->err_limit_time = *worker->env.now;
 311                 worker->err_limit_count = 1;
 312         }
 313         return err;
 314 }
 315
 316 /** check request sanity.
 317  * @param pkt: the wire packet to examine for sanity.
 318  * @param worker: parameters for checking.
 319  * @return error code, 0 OK, or -1 discard.
 320 */
 321 static int
 322 worker_check_request(sldns_buffer* pkt, struct worker* worker)
 323 {
 324         if(sldns_buffer_limit(pkt) < LDNS_HEADER_SIZE) {
 325                 verbose(VERB_QUERY, "request too short, discarded");
 326                 return -1;
 327         }
 328         if(sldns_buffer_limit(pkt) > NORMAL_UDP_SIZE &&
 329                 worker->daemon->cfg->harden_large_queries) {
 330                 verbose(VERB_QUERY, "request too large, discarded");
 331                 return -1;
 332         }
 333         if(LDNS_QR_WIRE(sldns_buffer_begin(pkt))) {
 334                 verbose(VERB_QUERY, "request has QR bit on, discarded");
 335                 return -1;
 336         }
 337         if(LDNS_TC_WIRE(sldns_buffer_begin(pkt))) {
 338                 LDNS_TC_CLR(sldns_buffer_begin(pkt));
 339                 verbose(VERB_QUERY, "request bad, has TC bit on");
 340                 return worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
 341         }
 342         if(LDNS_OPCODE_WIRE(sldns_buffer_begin(pkt)) != LDNS_PACKET_QUERY) {
 343                 verbose(VERB_QUERY, "request unknown opcode %d",
 344                         LDNS_OPCODE_WIRE(sldns_buffer_begin(pkt)));
 345                 return worker_err_ratelimit(worker, LDNS_RCODE_NOTIMPL);
 346         }
 347         if(LDNS_QDCOUNT(sldns_buffer_begin(pkt)) != 1) {
 348                 verbose(VERB_QUERY, "request wrong nr qd=%d",
 349                         LDNS_QDCOUNT(sldns_buffer_begin(pkt)));
 350                 return worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
 351         }
 352         if(LDNS_ANCOUNT(sldns_buffer_begin(pkt)) != 0) {
 353                 verbose(VERB_QUERY, "request wrong nr an=%d",
 354                         LDNS_ANCOUNT(sldns_buffer_begin(pkt)));
 355                 return worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
 356         }
 357         if(LDNS_NSCOUNT(sldns_buffer_begin(pkt)) != 0) {
 358                 verbose(VERB_QUERY, "request wrong nr ns=%d",
 359                         LDNS_NSCOUNT(sldns_buffer_begin(pkt)));
 360                 return worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
 361         }
 362         if(LDNS_ARCOUNT(sldns_buffer_begin(pkt)) > 1) {
 363                 verbose(VERB_QUERY, "request wrong nr ar=%d",
 364                         LDNS_ARCOUNT(sldns_buffer_begin(pkt)));
 365                 return worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
 366         }
 367         return 0;
 368 }
 369
 370 void
 371 worker_handle_control_cmd(struct tube* ATTR_UNUSED(tube), uint8_t* msg,
 372         size_t len, int error, void* arg)
 373 {
 374         struct worker* worker = (struct worker*)arg;
 375         enum worker_commands cmd;
 376         if(error != NETEVENT_NOERROR) {
 377                 free(msg);
 378                 if(error == NETEVENT_CLOSED)
 379                         comm_base_exit(worker->base);
 380                 else    log_info("control event: %d", error);
 381                 return;
 382         }
 383         if(len != sizeof(uint32_t)) {
 384                 fatal_exit("bad control msg length %d", (int)len);
 385         }
 386         cmd = sldns_read_uint32(msg);
 387         free(msg);
 388         switch(cmd) {
 389         case worker_cmd_quit:
 390                 verbose(VERB_ALGO, "got control cmd quit");
 391                 comm_base_exit(worker->base);
 392                 break;
 393         case worker_cmd_stats:
 394                 verbose(VERB_ALGO, "got control cmd stats");
 395                 server_stats_reply(worker, 1);
 396                 break;
 397         case worker_cmd_stats_noreset:
 398                 verbose(VERB_ALGO, "got control cmd stats_noreset");
 399                 server_stats_reply(worker, 0);
 400                 break;
 401         case worker_cmd_remote:
 402                 verbose(VERB_ALGO, "got control cmd remote");
 403                 daemon_remote_exec(worker);
 404                 break;
 405         default:
 406                 log_err("bad command %d", (int)cmd);
 407                 break;
 408         }
 409 }
 410
 411 /** check if a delegation is secure */
 412 static enum sec_status
 413 check_delegation_secure(struct reply_info *rep)
 414 {
 415         /* return smallest security status */
 416         size_t i;
 417         enum sec_status sec = sec_status_secure;
 418         enum sec_status s;
 419         size_t num = rep->an_numrrsets + rep->ns_numrrsets;
 420         /* check if answer and authority are OK */
 421         for(i=0; i<num; i++) {
 422                 s = ((struct packed_rrset_data*)rep->rrsets[i]->entry.data)
 423                         ->security;
 424                 if(s < sec)
 425                         sec = s;
 426         }
 427         /* in additional, only unchecked triggers revalidation */
 428         for(i=num; i<rep->rrset_count; i++) {
 429                 s = ((struct packed_rrset_data*)rep->rrsets[i]->entry.data)
 430                         ->security;
 431                 if(s == sec_status_unchecked)
 432                         return s;
 433         }
 434         return sec;
 435 }
 436
 437 /** remove nonsecure from a delegation referral additional section */
 438 static void
 439 deleg_remove_nonsecure_additional(struct reply_info* rep)
 440 {
 441         /* we can simply edit it, since we are working in the scratch region */
 442         size_t i;
 443         enum sec_status s;
 444
 445         for(i = rep->an_numrrsets+rep->ns_numrrsets; i<rep->rrset_count; i++) {
 446                 s = ((struct packed_rrset_data*)rep->rrsets[i]->entry.data)
 447                         ->security;
 448                 if(s != sec_status_secure) {
 449                         memmove(rep->rrsets+i, rep->rrsets+i+1,
 450                                 sizeof(struct ub_packed_rrset_key*)*
 451                                 (rep->rrset_count - i - 1));
 452                         rep->ar_numrrsets--;
 453                         rep->rrset_count--;
 454                         i--;
 455                 }
 456         }
 457 }
 458
 459 /** answer nonrecursive query from the cache */
 460 static int
 461 answer_norec_from_cache(struct worker* worker, struct query_info* qinfo,
 462         uint16_t id, uint16_t flags, struct comm_reply* repinfo,
 463         struct edns_data* edns)
 464 {
 465         /* for a nonrecursive query return either:
 466          *      o an error (servfail; we try to avoid this)
 467          *      o a delegation (closest we have; this routine tries that)
 468          *      o the answer (checked by answer_from_cache)
 469          *
 470          * So, grab a delegation from the rrset cache.
 471          * Then check if it needs validation, if so, this routine fails,
 472          * so that iterator can prime and validator can verify rrsets.
 473          */
 474         uint16_t udpsize = edns->udp_size;
 475         int secure = 0;
 476         time_t timenow = *worker->env.now;
 477         int must_validate = (!(flags&BIT_CD) || worker->env.cfg->ignore_cd)
 478                 && worker->env.need_to_validate;
 479         struct dns_msg *msg = NULL;
 480         struct delegpt *dp;
 481
 482         dp = dns_cache_find_delegation(&worker->env, qinfo->qname,
 483                 qinfo->qname_len, qinfo->qtype, qinfo->qclass,
 484                 worker->scratchpad, &msg, timenow);
 485         if(!dp) { /* no delegation, need to reprime */
 486                 return 0;
 487         }
 488         if(must_validate) {
 489                 switch(check_delegation_secure(msg->rep)) {
 490                 case sec_status_unchecked:
 491                         /* some rrsets have not been verified yet, go and
 492                          * let validator do that */
 493                         return 0;
 494                 case sec_status_bogus:
 495                         /* some rrsets are bogus, reply servfail */
 496                         edns->edns_version = EDNS_ADVERTISED_VERSION;
 497                         edns->udp_size = EDNS_ADVERTISED_SIZE;
 498                         edns->ext_rcode = 0;
 499                         edns->bits &= EDNS_DO;
 500                         if(!edns_opt_inplace_reply(edns, worker->scratchpad))
 501                                 return 0;
 502                         error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
 503                                 &msg->qinfo, id, flags, edns);
 504                         if(worker->stats.extended) {
 505                                 worker->stats.ans_bogus++;
 506                                 worker->stats.ans_rcode[LDNS_RCODE_SERVFAIL]++;
 507                         }
 508                         return 1;
 509                 case sec_status_secure:
 510                         /* all rrsets are secure */
 511                         /* remove non-secure rrsets from the add. section*/
 512                         if(worker->env.cfg->val_clean_additional)
 513                                 deleg_remove_nonsecure_additional(msg->rep);
 514                         secure = 1;
 515                         break;
 516                 case sec_status_indeterminate:
 517                 case sec_status_insecure:
 518                 default:
 519                         /* not secure */
 520                         secure = 0;
 521                         break;
 522                 }
 523         }
 524         /* return this delegation from the cache */
 525         edns->edns_version = EDNS_ADVERTISED_VERSION;
 526         edns->udp_size = EDNS_ADVERTISED_SIZE;
 527         edns->ext_rcode = 0;
 528         edns->bits &= EDNS_DO;
 529         if(!edns_opt_inplace_reply(edns, worker->scratchpad))
 530                 return 0;
 531         msg->rep->flags |= BIT_QR|BIT_RA;
 532         if(!reply_info_answer_encode(&msg->qinfo, msg->rep, id, flags,
 533                 repinfo->c->buffer, 0, 1, worker->scratchpad,
 534                 udpsize, edns, (int)(edns->bits & EDNS_DO), secure)) {
 535                 error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
 536                         &msg->qinfo, id, flags, edns);
 537         }
 538         if(worker->stats.extended) {
 539                 if(secure) worker->stats.ans_secure++;
 540                 server_stats_insrcode(&worker->stats, repinfo->c->buffer);
 541         }
 542         return 1;
 543 }
 544
 545 /** answer query from the cache */
 546 static int
 547 answer_from_cache(struct worker* worker, struct query_info* qinfo,
 548         struct reply_info* rep, uint16_t id, uint16_t flags,
 549         struct comm_reply* repinfo, struct edns_data* edns)
 550 {
 551         time_t timenow = *worker->env.now;
 552         uint16_t udpsize = edns->udp_size;
 553         int secure;
 554         int must_validate = (!(flags&BIT_CD) || worker->env.cfg->ignore_cd)
 555                 && worker->env.need_to_validate;
 556         /* see if it is possible */
 557         if(rep->ttl < timenow) {
 558                 /* the rrsets may have been updated in the meantime.
 559                  * we will refetch the message format from the
 560                  * authoritative server
 561                  */
 562                 return 0;
 563         }
 564         if(!rrset_array_lock(rep->ref, rep->rrset_count, timenow))
 565                 return 0;
 566         /* locked and ids and ttls are OK. */
 567         /* check CNAME chain (if any) */
 568         if(rep->an_numrrsets > 0 && (rep->rrsets[0]->rk.type ==
 569                 htons(LDNS_RR_TYPE_CNAME) || rep->rrsets[0]->rk.type ==
 570                 htons(LDNS_RR_TYPE_DNAME))) {
 571                 if(!reply_check_cname_chain(qinfo, rep)) {
 572                         /* cname chain invalid, redo iterator steps */
 573                         verbose(VERB_ALGO, "Cache reply: cname chain broken");
 574                 bail_out:
 575                         rrset_array_unlock_touch(worker->env.rrset_cache,
 576                                 worker->scratchpad, rep->ref, rep->rrset_count);
 577                         return 0;
 578                 }
 579         }
 580         /* check security status of the cached answer */
 581         if( rep->security == sec_status_bogus && must_validate) {
 582                 /* BAD cached */
 583                 edns->edns_version = EDNS_ADVERTISED_VERSION;
 584                 edns->udp_size = EDNS_ADVERTISED_SIZE;
 585                 edns->ext_rcode = 0;
 586                 edns->bits &= EDNS_DO;
 587                 if(!edns_opt_inplace_reply(edns, worker->scratchpad))
 588                         return 0;
 589                 error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
 590                         qinfo, id, flags, edns);
 591                 rrset_array_unlock_touch(worker->env.rrset_cache,
 592                         worker->scratchpad, rep->ref, rep->rrset_count);
 593                 if(worker->stats.extended) {
 594                         worker->stats.ans_bogus ++;
 595                         worker->stats.ans_rcode[LDNS_RCODE_SERVFAIL] ++;
 596                 }
 597                 return 1;
 598         } else if( rep->security == sec_status_unchecked && must_validate) {
 599                 verbose(VERB_ALGO, "Cache reply: unchecked entry needs "
 600                         "validation");
 601                 goto bail_out; /* need to validate cache entry first */
 602         } else if(rep->security == sec_status_secure) {
 603                 if(reply_all_rrsets_secure(rep))
 604                         secure = 1;
 605                 else    {
 606                         if(must_validate) {
 607                                 verbose(VERB_ALGO, "Cache reply: secure entry"
 608                                         " changed status");
 609                                 goto bail_out; /* rrset changed, re-verify */
 610                         }
 611                         secure = 0;
 612                 }
 613         } else  secure = 0;
 614
 615         edns->edns_version = EDNS_ADVERTISED_VERSION;
 616         edns->udp_size = EDNS_ADVERTISED_SIZE;
 617         edns->ext_rcode = 0;
 618         edns->bits &= EDNS_DO;
 619         if(!edns_opt_inplace_reply(edns, worker->scratchpad))
 620                 return 0;
 621         if(!reply_info_answer_encode(qinfo, rep, id, flags,
 622                 repinfo->c->buffer, timenow, 1, worker->scratchpad,
 623                 udpsize, edns, (int)(edns->bits & EDNS_DO), secure)) {
 624                 error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
 625                         qinfo, id, flags, edns);
 626         }
 627         /* cannot send the reply right now, because blocking network syscall
 628          * is bad while holding locks. */
 629         rrset_array_unlock_touch(worker->env.rrset_cache, worker->scratchpad,
 630                 rep->ref, rep->rrset_count);
 631         if(worker->stats.extended) {
 632                 if(secure) worker->stats.ans_secure++;
 633                 server_stats_insrcode(&worker->stats, repinfo->c->buffer);
 634         }
 635         /* go and return this buffer to the client */
 636         return 1;
 637 }
 638
 639 /** Reply to client and perform prefetch to keep cache up to date */
 640 static void
 641 reply_and_prefetch(struct worker* worker, struct query_info* qinfo,
 642         uint16_t flags, struct comm_reply* repinfo, time_t leeway)
 643 {
 644         /* first send answer to client to keep its latency
 645          * as small as a cachereply */
 646         comm_point_send_reply(repinfo);
 647         server_stats_prefetch(&worker->stats, worker);
 648
 649         /* create the prefetch in the mesh as a normal lookup without
 650          * client addrs waiting, which has the cache blacklisted (to bypass
 651          * the cache and go to the network for the data). */
 652         /* this (potentially) runs the mesh for the new query */
 653         mesh_new_prefetch(worker->env.mesh, qinfo, flags, leeway +
 654                 PREFETCH_EXPIRY_ADD);
 655 }
 656
 657 /**
 658  * Fill CH class answer into buffer. Keeps query.
 659  * @param pkt: buffer
 660  * @param str: string to put into text record (<255).
 661  * @param edns: edns reply information.
 662  * @param worker: worker with scratch region.
 663  */
 664 static void
 665 chaos_replystr(sldns_buffer* pkt, const char* str, struct edns_data* edns,
 666         struct worker* worker)
 667 {
 668         size_t len = strlen(str);
 669         unsigned int rd = LDNS_RD_WIRE(sldns_buffer_begin(pkt));
 670         unsigned int cd = LDNS_CD_WIRE(sldns_buffer_begin(pkt));
 671         if(len>255) len=255; /* cap size of TXT record */
 672         sldns_buffer_clear(pkt);
 673         sldns_buffer_skip(pkt, (ssize_t)sizeof(uint16_t)); /* skip id */
 674         sldns_buffer_write_u16(pkt, (uint16_t)(BIT_QR|BIT_RA));
 675         if(rd) LDNS_RD_SET(sldns_buffer_begin(pkt));
 676         if(cd) LDNS_CD_SET(sldns_buffer_begin(pkt));
 677         sldns_buffer_write_u16(pkt, 1); /* qdcount */
 678         sldns_buffer_write_u16(pkt, 1); /* ancount */
 679         sldns_buffer_write_u16(pkt, 0); /* nscount */
 680         sldns_buffer_write_u16(pkt, 0); /* arcount */
 681         (void)query_dname_len(pkt); /* skip qname */
 682         sldns_buffer_skip(pkt, (ssize_t)sizeof(uint16_t)); /* skip qtype */
 683         sldns_buffer_skip(pkt, (ssize_t)sizeof(uint16_t)); /* skip qclass */
 684         sldns_buffer_write_u16(pkt, 0xc00c); /* compr ptr to query */
 685         sldns_buffer_write_u16(pkt, LDNS_RR_TYPE_TXT);
 686         sldns_buffer_write_u16(pkt, LDNS_RR_CLASS_CH);
 687         sldns_buffer_write_u32(pkt, 0); /* TTL */
 688         sldns_buffer_write_u16(pkt, sizeof(uint8_t) + len);
 689         sldns_buffer_write_u8(pkt, len);
 690         sldns_buffer_write(pkt, str, len);
 691         sldns_buffer_flip(pkt);
 692         edns->edns_version = EDNS_ADVERTISED_VERSION;
 693         edns->udp_size = EDNS_ADVERTISED_SIZE;
 694         edns->bits &= EDNS_DO;
 695         if(!edns_opt_inplace_reply(edns, worker->scratchpad))
 696                 edns->opt_list = NULL;
 697         attach_edns_record(pkt, edns);
 698 }
 699
 700 /**
 701  * Answer CH class queries.
 702  * @param w: worker
 703  * @param qinfo: query info. Pointer into packet buffer.
 704  * @param edns: edns info from query.
 705  * @param pkt: packet buffer.
 706  * @return: true if a reply is to be sent.
 707  */
 708 static int
 709 answer_chaos(struct worker* w, struct query_info* qinfo,
 710         struct edns_data* edns, sldns_buffer* pkt)
 711 {
 712         struct config_file* cfg = w->env.cfg;
 713         if(qinfo->qtype != LDNS_RR_TYPE_ANY && qinfo->qtype != LDNS_RR_TYPE_TXT)
 714                 return 0;
 715         if(query_dname_compare(qinfo->qname,
 716                 (uint8_t*)"\002id\006server") == 0 ||
 717                 query_dname_compare(qinfo->qname,
 718                 (uint8_t*)"\010hostname\004bind") == 0)
 719         {
 720                 if(cfg->hide_identity)
 721                         return 0;
 722                 if(cfg->identity==NULL || cfg->identity[0]==0) {
 723                         char buf[MAXHOSTNAMELEN+1];
 724                         if (gethostname(buf, MAXHOSTNAMELEN) == 0) {
 725                                 buf[MAXHOSTNAMELEN] = 0;
 726                                 chaos_replystr(pkt, buf, edns, w);
 727                         } else  {
 728                                 log_err("gethostname: %s", strerror(errno));
 729                                 chaos_replystr(pkt, "no hostname", edns, w);
 730                         }
 731                 }
 732                 else    chaos_replystr(pkt, cfg->identity, edns, w);
 733                 return 1;
 734         }
 735         if(query_dname_compare(qinfo->qname,
 736                 (uint8_t*)"\007version\006server") == 0 ||
 737                 query_dname_compare(qinfo->qname,
 738                 (uint8_t*)"\007version\004bind") == 0)
 739         {
 740                 if(cfg->hide_version)
 741                         return 0;
 742                 if(cfg->version==NULL || cfg->version[0]==0)
 743                         chaos_replystr(pkt, PACKAGE_STRING, edns, w);
 744                 else    chaos_replystr(pkt, cfg->version, edns, w);
 745                 return 1;
 746         }
 747         return 0;
 748 }
 749
 750 static int
 751 deny_refuse(struct comm_point* c, enum acl_access acl,
 752         enum acl_access deny, enum acl_access refuse,
 753         struct worker* worker, struct comm_reply* repinfo)
 754 {
 755         if(acl == deny) {
 756                 comm_point_drop_reply(repinfo);
 757                 if(worker->stats.extended)
 758                         worker->stats.unwanted_queries++;
 759                 return 0;
 760         } else if(acl == refuse) {
 761                 log_addr(VERB_ALGO, "refused query from",
 762                         &repinfo->addr, repinfo->addrlen);
 763                 log_buf(VERB_ALGO, "refuse", c->buffer);
 764                 if(worker->stats.extended)
 765                         worker->stats.unwanted_queries++;
 766                 if(worker_check_request(c->buffer, worker) == -1) {
 767                         comm_point_drop_reply(repinfo);
 768                         return 0; /* discard this */
 769                 }
 770                 sldns_buffer_set_limit(c->buffer, LDNS_HEADER_SIZE);
 771                 sldns_buffer_write_at(c->buffer, 4,
 772                         (uint8_t*)"\0\0\0\0\0\0\0\0", 8);
 773                 LDNS_QR_SET(sldns_buffer_begin(c->buffer));
 774                 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
 775                         LDNS_RCODE_REFUSED);
 776                 sldns_buffer_set_position(c->buffer, LDNS_HEADER_SIZE);
 777                 sldns_buffer_flip(c->buffer);
 778                 return 1;
 779         }
 780
 781         return -1;
 782 }
 783
 784 static int
 785 deny_refuse_all(struct comm_point* c, enum acl_access acl,
 786         struct worker* worker, struct comm_reply* repinfo)
 787 {
 788         return deny_refuse(c, acl, acl_deny, acl_refuse, worker, repinfo);
 789 }
 790
 791 static int
 792 deny_refuse_non_local(struct comm_point* c, enum acl_access acl,
 793         struct worker* worker, struct comm_reply* repinfo)
 794 {
 795         return deny_refuse(c, acl, acl_deny_non_local, acl_refuse_non_local, worker, repinfo);
 796 }
 797
 798 int
 799 worker_handle_request(struct comm_point* c, void* arg, int error,
 800         struct comm_reply* repinfo)
 801 {
 802         struct worker* worker = (struct worker*)arg;
 803         int ret;
 804         hashvalue_t h;
 805         struct lruhash_entry* e;
 806         struct query_info qinfo;
 807         struct edns_data edns;
 808         enum acl_access acl;
 809         struct acl_addr* acladdr;
 810         int rc = 0;
 811
 812         if(error != NETEVENT_NOERROR) {
 813                 /* some bad tcp query DNS formats give these error calls */
 814                 verbose(VERB_ALGO, "handle request called with err=%d", error);
 815                 return 0;
 816         }
 817 #ifdef USE_DNSTAP
 818         if(worker->dtenv.log_client_query_messages)
 819                 dt_msg_send_client_query(&worker->dtenv, &repinfo->addr, c->type,
 820                         c->buffer);
 821 #endif
 822         acladdr = acl_addr_lookup(worker->daemon->acl, &repinfo->addr,
 823                 repinfo->addrlen);
 824         acl = acl_get_control(acladdr);
 825         if((ret=deny_refuse_all(c, acl, worker, repinfo)) != -1)
 826         {
 827                 if(ret == 1)
 828                         goto send_reply;
 829                 return ret;
 830         }
 831         if((ret=worker_check_request(c->buffer, worker)) != 0) {
 832                 verbose(VERB_ALGO, "worker check request: bad query.");
 833                 log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
 834                 if(ret != -1) {
 835                         LDNS_QR_SET(sldns_buffer_begin(c->buffer));
 836                         LDNS_RCODE_SET(sldns_buffer_begin(c->buffer), ret);
 837                         return 1;
 838                 }
 839                 comm_point_drop_reply(repinfo);
 840                 return 0;
 841         }
 842         worker->stats.num_queries++;
 843         /* see if query is in the cache */
 844         if(!query_info_parse(&qinfo, c->buffer)) {
 845                 verbose(VERB_ALGO, "worker parse request: formerror.");
 846                 log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
 847                 if(worker_err_ratelimit(worker, LDNS_RCODE_FORMERR) == -1) {
 848                         comm_point_drop_reply(repinfo);
 849                         return 0;
 850                 }
 851                 sldns_buffer_rewind(c->buffer);
 852                 LDNS_QR_SET(sldns_buffer_begin(c->buffer));
 853                 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
 854                         LDNS_RCODE_FORMERR);
 855                 server_stats_insrcode(&worker->stats, c->buffer);
 856                 goto send_reply;
 857         }
 858         if(worker->env.cfg->log_queries) {
 859                 char ip[128];
 860                 addr_to_str(&repinfo->addr, repinfo->addrlen, ip, sizeof(ip));
 861                 log_nametypeclass(0, ip, qinfo.qname, qinfo.qtype, qinfo.qclass);
 862         }
 863         if(qinfo.qtype == LDNS_RR_TYPE_AXFR ||
 864                 qinfo.qtype == LDNS_RR_TYPE_IXFR) {
 865                 verbose(VERB_ALGO, "worker request: refused zone transfer.");
 866                 log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
 867                 sldns_buffer_rewind(c->buffer);
 868                 LDNS_QR_SET(sldns_buffer_begin(c->buffer));
 869                 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
 870                         LDNS_RCODE_REFUSED);
 871                 if(worker->stats.extended) {
 872                         worker->stats.qtype[qinfo.qtype]++;
 873                         server_stats_insrcode(&worker->stats, c->buffer);
 874                 }
 875                 goto send_reply;
 876         }
 877         if((ret=parse_edns_from_pkt(c->buffer, &edns, worker->scratchpad)) != 0) {
 878                 struct edns_data reply_edns;
 879                 verbose(VERB_ALGO, "worker parse edns: formerror.");
 880                 log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
 881                 memset(&reply_edns, 0, sizeof(reply_edns));
 882                 reply_edns.edns_present = 1;
 883                 reply_edns.udp_size = EDNS_ADVERTISED_SIZE;
 884                 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer), ret);
 885                 error_encode(c->buffer, ret, &qinfo,
 886                         *(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
 887                         sldns_buffer_read_u16_at(c->buffer, 2), &reply_edns);
 888                 regional_free_all(worker->scratchpad);
 889                 server_stats_insrcode(&worker->stats, c->buffer);
 890                 goto send_reply;
 891         }
 892         if(edns.edns_present && edns.edns_version != 0) {
 893                 edns.ext_rcode = (uint8_t)(EDNS_RCODE_BADVERS>>4);
 894                 edns.edns_version = EDNS_ADVERTISED_VERSION;
 895                 edns.udp_size = EDNS_ADVERTISED_SIZE;
 896                 edns.bits &= EDNS_DO;
 897                 edns.opt_list = NULL;
 898                 verbose(VERB_ALGO, "query with bad edns version.");
 899                 log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
 900                 error_encode(c->buffer, EDNS_RCODE_BADVERS&0xf, &qinfo,
 901                         *(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
 902                         sldns_buffer_read_u16_at(c->buffer, 2), NULL);
 903                 attach_edns_record(c->buffer, &edns);
 904                 regional_free_all(worker->scratchpad);
 905                 goto send_reply;
 906         }
 907         if(edns.edns_present && edns.udp_size < NORMAL_UDP_SIZE &&
 908                 worker->daemon->cfg->harden_short_bufsize) {
 909                 verbose(VERB_QUERY, "worker request: EDNS bufsize %d ignored",
 910                         (int)edns.udp_size);
 911                 log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
 912                 edns.udp_size = NORMAL_UDP_SIZE;
 913         }
 914         if(edns.udp_size > worker->daemon->cfg->max_udp_size &&
 915                 c->type == comm_udp) {
 916                 verbose(VERB_QUERY,
 917                         "worker request: max UDP reply size modified"
 918                         " (%d to max-udp-size)", (int)edns.udp_size);
 919                 log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
 920                 edns.udp_size = worker->daemon->cfg->max_udp_size;
 921         }
 922         if(edns.udp_size < LDNS_HEADER_SIZE) {
 923                 verbose(VERB_ALGO, "worker request: edns is too small.");
 924                 log_addr(VERB_CLIENT, "from", &repinfo->addr, repinfo->addrlen);
 925                 LDNS_QR_SET(sldns_buffer_begin(c->buffer));
 926                 LDNS_TC_SET(sldns_buffer_begin(c->buffer));
 927                 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
 928                         LDNS_RCODE_SERVFAIL);
 929                 sldns_buffer_set_position(c->buffer, LDNS_HEADER_SIZE);
 930                 sldns_buffer_write_at(c->buffer, 4,
 931                         (uint8_t*)"\0\0\0\0\0\0\0\0", 8);
 932                 sldns_buffer_flip(c->buffer);
 933                 regional_free_all(worker->scratchpad);
 934                 goto send_reply;
 935         }
 936         if(worker->stats.extended)
 937                 server_stats_insquery(&worker->stats, c, qinfo.qtype,
 938                         qinfo.qclass, &edns, repinfo);
 939         if(c->type != comm_udp)
 940                 edns.udp_size = 65535; /* max size for TCP replies */
 941         if(qinfo.qclass == LDNS_RR_CLASS_CH && answer_chaos(worker, &qinfo,
 942                 &edns, c->buffer)) {
 943                 server_stats_insrcode(&worker->stats, c->buffer);
 944                 regional_free_all(worker->scratchpad);
 945                 goto send_reply;
 946         }
 947         if(local_zones_answer(worker->daemon->local_zones, &qinfo, &edns,
 948                 c->buffer, worker->scratchpad, repinfo,
 949                 acladdr->taglist, acladdr->taglen, acladdr->tag_actions,
 950                 acladdr->tag_actions_size, acladdr->tag_datas,
 951                 acladdr->tag_datas_size, worker->daemon->cfg->tagname,
 952                 worker->daemon->cfg->num_tags)) {
 953                 regional_free_all(worker->scratchpad);
 954                 if(sldns_buffer_limit(c->buffer) == 0) {
 955                         comm_point_drop_reply(repinfo);
 956                         return 0;
 957                 }
 958                 server_stats_insrcode(&worker->stats, c->buffer);
 959                 goto send_reply;
 960         }
 961
 962         /* We've looked in our local zones. If the answer isn't there, we
 963          * might need to bail out based on ACLs now. */
 964         if((ret=deny_refuse_non_local(c, acl, worker, repinfo)) != -1)
 965         {
 966                 regional_free_all(worker->scratchpad);
 967                 if(ret == 1)
 968                         goto send_reply;
 969                 return ret;
 970         }
 971
 972         /* If this request does not have the recursion bit set, verify
 973          * ACLs allow the snooping. */
 974         if(!(LDNS_RD_WIRE(sldns_buffer_begin(c->buffer))) &&
 975                 acl != acl_allow_snoop ) {
 976                 sldns_buffer_set_limit(c->buffer, LDNS_HEADER_SIZE);
 977                 sldns_buffer_write_at(c->buffer, 4,
 978                         (uint8_t*)"\0\0\0\0\0\0\0\0", 8);
 979                 LDNS_QR_SET(sldns_buffer_begin(c->buffer));
 980                 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
 981                         LDNS_RCODE_REFUSED);
 982                 sldns_buffer_flip(c->buffer);
 983                 regional_free_all(worker->scratchpad);
 984                 server_stats_insrcode(&worker->stats, c->buffer);
 985                 log_addr(VERB_ALGO, "refused nonrec (cache snoop) query from",
 986                         &repinfo->addr, repinfo->addrlen);
 987                 goto send_reply;
 988         }
 989         h = query_info_hash(&qinfo, sldns_buffer_read_u16_at(c->buffer, 2));
 990         if((e=slabhash_lookup(worker->env.msg_cache, h, &qinfo, 0))) {
 991                 /* answer from cache - we have acquired a readlock on it */
 992                 if(answer_from_cache(worker, &qinfo,
 993                         (struct reply_info*)e->data,
 994                         *(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
 995                         sldns_buffer_read_u16_at(c->buffer, 2), repinfo,
 996                         &edns)) {
 997                         /* prefetch it if the prefetch TTL expired */
 998                         if(worker->env.cfg->prefetch && *worker->env.now >=
 999                                 ((struct reply_info*)e->data)->prefetch_ttl) {
1000                                 time_t leeway = ((struct reply_info*)e->
1001                                         data)->ttl - *worker->env.now;
1002                                 lock_rw_unlock(&e->lock);
1003                                 reply_and_prefetch(worker, &qinfo,
1004                                         sldns_buffer_read_u16_at(c->buffer, 2),
1005                                         repinfo, leeway);
1006                                 rc = 0;
1007                                 regional_free_all(worker->scratchpad);
1008                                 goto send_reply_rc;
1009                         }
1010                         lock_rw_unlock(&e->lock);
1011                         regional_free_all(worker->scratchpad);
1012                         goto send_reply;
1013                 }
1014                 verbose(VERB_ALGO, "answer from the cache failed");
1015                 lock_rw_unlock(&e->lock);
1016         }
1017         if(!LDNS_RD_WIRE(sldns_buffer_begin(c->buffer))) {
1018                 if(answer_norec_from_cache(worker, &qinfo,
1019                         *(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
1020                         sldns_buffer_read_u16_at(c->buffer, 2), repinfo,
1021                         &edns)) {
1022                         regional_free_all(worker->scratchpad);
1023                         goto send_reply;
1024                 }
1025                 verbose(VERB_ALGO, "answer norec from cache -- "
1026                         "need to validate or not primed");
1027         }
1028         sldns_buffer_rewind(c->buffer);
1029         server_stats_querymiss(&worker->stats, worker);
1030
1031         if(verbosity >= VERB_CLIENT) {
1032                 if(c->type == comm_udp)
1033                         log_addr(VERB_CLIENT, "udp request from",
1034                                 &repinfo->addr, repinfo->addrlen);
1035                 else    log_addr(VERB_CLIENT, "tcp request from",
1036                                 &repinfo->addr, repinfo->addrlen);
1037         }
1038
1039         /* grab a work request structure for this new request */
1040         mesh_new_client(worker->env.mesh, &qinfo,
1041                 sldns_buffer_read_u16_at(c->buffer, 2),
1042                 &edns, repinfo, *(uint16_t*)(void *)sldns_buffer_begin(c->buffer));
1043         regional_free_all(worker->scratchpad);
1044         worker_mem_report(worker, NULL);
1045         return 0;
1046
1047 send_reply:
1048         rc = 1;
1049 send_reply_rc:
1050 #ifdef USE_DNSTAP
1051         if(worker->dtenv.log_client_response_messages)
1052                 dt_msg_send_client_response(&worker->dtenv, &repinfo->addr,
1053                         c->type, c->buffer);
1054 #endif
1055         return rc;
1056 }
1057
1058 void
1059 worker_sighandler(int sig, void* arg)
1060 {
1061         /* note that log, print, syscalls here give race conditions.
1062          * And cause hangups if the log-lock is held by the application. */
1063         struct worker* worker = (struct worker*)arg;
1064         switch(sig) {
1065 #ifdef SIGHUP
1066                 case SIGHUP:
1067                         comm_base_exit(worker->base);
1068                         break;
1069 #endif
1070                 case SIGINT:
1071                         worker->need_to_exit = 1;
1072                         comm_base_exit(worker->base);
1073                         break;
1074 #ifdef SIGQUIT
1075                 case SIGQUIT:
1076                         worker->need_to_exit = 1;
1077                         comm_base_exit(worker->base);
1078                         break;
1079 #endif
1080                 case SIGTERM:
1081                         worker->need_to_exit = 1;
1082                         comm_base_exit(worker->base);
1083                         break;
1084                 default:
1085                         /* unknown signal, ignored */
1086                         break;
1087         }
1088 }
1089
1090 /** restart statistics timer for worker, if enabled */
1091 static void
1092 worker_restart_timer(struct worker* worker)
1093 {
1094         if(worker->env.cfg->stat_interval > 0) {
1095                 struct timeval tv;
1096 #ifndef S_SPLINT_S
1097                 tv.tv_sec = worker->env.cfg->stat_interval;
1098                 tv.tv_usec = 0;
1099 #endif
1100                 comm_timer_set(worker->stat_timer, &tv);
1101         }
1102 }
1103
1104 void worker_stat_timer_cb(void* arg)
1105 {
1106         struct worker* worker = (struct worker*)arg;
1107         server_stats_log(&worker->stats, worker, worker->thread_num);
1108         mesh_stats(worker->env.mesh, "mesh has");
1109         worker_mem_report(worker, NULL);
1110         if(!worker->daemon->cfg->stat_cumulative) {
1111                 worker_stats_clear(worker);
1112         }
1113         /* start next timer */
1114         worker_restart_timer(worker);
1115 }
1116
1117 void worker_probe_timer_cb(void* arg)
1118 {
1119         struct worker* worker = (struct worker*)arg;
1120         struct timeval tv;
1121 #ifndef S_SPLINT_S
1122         tv.tv_sec = (time_t)autr_probe_timer(&worker->env);
1123         tv.tv_usec = 0;
1124 #endif
1125         if(tv.tv_sec != 0)
1126                 comm_timer_set(worker->env.probe_timer, &tv);
1127 }
1128
1129 struct worker*
1130 worker_create(struct daemon* daemon, int id, int* ports, int n)
1131 {
1132         unsigned int seed;
1133         struct worker* worker = (struct worker*)calloc(1,
1134                 sizeof(struct worker));
1135         if(!worker)
1136                 return NULL;
1137         worker->numports = n;
1138         worker->ports = (int*)memdup(ports, sizeof(int)*n);
1139         if(!worker->ports) {
1140                 free(worker);
1141                 return NULL;
1142         }
1143         worker->daemon = daemon;
1144         worker->thread_num = id;
1145         if(!(worker->cmd = tube_create())) {
1146                 free(worker->ports);
1147                 free(worker);
1148                 return NULL;
1149         }
1150         /* create random state here to avoid locking trouble in RAND_bytes */
1151         seed = (unsigned int)time(NULL) ^ (unsigned int)getpid() ^
1152                 (((unsigned int)worker->thread_num)<<17);
1153                 /* shift thread_num so it does not match out pid bits */
1154         if(!(worker->rndstate = ub_initstate(seed, daemon->rand))) {
1155                 seed = 0;
1156                 log_err("could not init random numbers.");
1157                 tube_delete(worker->cmd);
1158                 free(worker->ports);
1159                 free(worker);
1160                 return NULL;
1161         }
1162         seed = 0;
1163 #ifdef USE_DNSTAP
1164         if(daemon->cfg->dnstap) {
1165                 log_assert(daemon->dtenv != NULL);
1166                 memcpy(&worker->dtenv, daemon->dtenv, sizeof(struct dt_env));
1167                 if(!dt_init(&worker->dtenv))
1168                         fatal_exit("dt_init failed");
1169         }
1170 #endif
1171         return worker;
1172 }
1173
1174 int
1175 worker_init(struct worker* worker, struct config_file *cfg,
1176         struct listen_port* ports, int do_sigs)
1177 {
1178 #ifdef USE_DNSTAP
1179         struct dt_env* dtenv = &worker->dtenv;
1180 #else
1181         void* dtenv = NULL;
1182 #endif
1183         worker->need_to_exit = 0;
1184         worker->base = comm_base_create(do_sigs);
1185         if(!worker->base) {
1186                 log_err("could not create event handling base");
1187                 worker_delete(worker);
1188                 return 0;
1189         }
1190         comm_base_set_slow_accept_handlers(worker->base, &worker_stop_accept,
1191                 &worker_start_accept, worker);
1192         if(do_sigs) {
1193 #ifdef SIGHUP
1194                 ub_thread_sig_unblock(SIGHUP);
1195 #endif
1196                 ub_thread_sig_unblock(SIGINT);
1197 #ifdef SIGQUIT
1198                 ub_thread_sig_unblock(SIGQUIT);
1199 #endif
1200                 ub_thread_sig_unblock(SIGTERM);
1201 #ifndef LIBEVENT_SIGNAL_PROBLEM
1202                 worker->comsig = comm_signal_create(worker->base,
1203                         worker_sighandler, worker);
1204                 if(!worker->comsig
1205 #ifdef SIGHUP
1206                         || !comm_signal_bind(worker->comsig, SIGHUP)
1207 #endif
1208 #ifdef SIGQUIT
1209                         || !comm_signal_bind(worker->comsig, SIGQUIT)
1210 #endif
1211                         || !comm_signal_bind(worker->comsig, SIGTERM)
1212                         || !comm_signal_bind(worker->comsig, SIGINT)) {
1213                         log_err("could not create signal handlers");
1214                         worker_delete(worker);
1215                         return 0;
1216                 }
1217 #endif /* LIBEVENT_SIGNAL_PROBLEM */
1218                 if(!daemon_remote_open_accept(worker->daemon->rc,
1219                         worker->daemon->rc_ports, worker)) {
1220                         worker_delete(worker);
1221                         return 0;
1222                 }
1223 #ifdef UB_ON_WINDOWS
1224                 wsvc_setup_worker(worker);
1225 #endif /* UB_ON_WINDOWS */
1226         } else { /* !do_sigs */
1227                 worker->comsig = NULL;
1228         }
1229         worker->front = listen_create(worker->base, ports,
1230                 cfg->msg_buffer_size, (int)cfg->incoming_num_tcp,
1231                 worker->daemon->listen_sslctx, dtenv, worker_handle_request,
1232                 worker);
1233         if(!worker->front) {
1234                 log_err("could not create listening sockets");
1235                 worker_delete(worker);
1236                 return 0;
1237         }
1238         worker->back = outside_network_create(worker->base,
1239                 cfg->msg_buffer_size, (size_t)cfg->outgoing_num_ports,
1240                 cfg->out_ifs, cfg->num_out_ifs, cfg->do_ip4, cfg->do_ip6,
1241                 cfg->do_tcp?cfg->outgoing_num_tcp:0,
1242                 worker->daemon->env->infra_cache, worker->rndstate,
1243                 cfg->use_caps_bits_for_id, worker->ports, worker->numports,
1244                 cfg->unwanted_threshold, cfg->outgoing_tcp_mss,
1245                 &worker_alloc_cleanup, worker,
1246                 cfg->do_udp, worker->daemon->connect_sslctx, cfg->delay_close,
1247                 dtenv);
1248         if(!worker->back) {
1249                 log_err("could not create outgoing sockets");
1250                 worker_delete(worker);
1251                 return 0;
1252         }
1253         /* start listening to commands */
1254         if(!tube_setup_bg_listen(worker->cmd, worker->base,
1255                 &worker_handle_control_cmd, worker)) {
1256                 log_err("could not create control compt.");
1257                 worker_delete(worker);
1258                 return 0;
1259         }
1260         worker->stat_timer = comm_timer_create(worker->base,
1261                 worker_stat_timer_cb, worker);
1262         if(!worker->stat_timer) {
1263                 log_err("could not create statistics timer");
1264         }
1265
1266         /* we use the msg_buffer_size as a good estimate for what the
1267          * user wants for memory usage sizes */
1268         worker->scratchpad = regional_create_custom(cfg->msg_buffer_size);
1269         if(!worker->scratchpad) {
1270                 log_err("malloc failure");
1271                 worker_delete(worker);
1272                 return 0;
1273         }
1274
1275         server_stats_init(&worker->stats, cfg);
1276         alloc_init(&worker->alloc, &worker->daemon->superalloc,
1277                 worker->thread_num);
1278         alloc_set_id_cleanup(&worker->alloc, &worker_alloc_cleanup, worker);
1279         worker->env = *worker->daemon->env;
1280         comm_base_timept(worker->base, &worker->env.now, &worker->env.now_tv);
1281         if(worker->thread_num == 0)
1282                 log_set_time(worker->env.now);
1283         worker->env.worker = worker;
1284         worker->env.send_query = &worker_send_query;
1285         worker->env.alloc = &worker->alloc;
1286         worker->env.rnd = worker->rndstate;
1287         worker->env.scratch = worker->scratchpad;
1288         worker->env.mesh = mesh_create(&worker->daemon->mods, &worker->env);
1289         worker->env.detach_subs = &mesh_detach_subs;
1290         worker->env.attach_sub = &mesh_attach_sub;
1291         worker->env.kill_sub = &mesh_state_delete;
1292         worker->env.detect_cycle = &mesh_detect_cycle;
1293         worker->env.scratch_buffer = sldns_buffer_new(cfg->msg_buffer_size);
1294         if(!(worker->env.fwds = forwards_create()) ||
1295                 !forwards_apply_cfg(worker->env.fwds, cfg)) {
1296                 log_err("Could not set forward zones");
1297                 worker_delete(worker);
1298                 return 0;
1299         }
1300         if(!(worker->env.hints = hints_create()) ||
1301                 !hints_apply_cfg(worker->env.hints, cfg)) {
1302                 log_err("Could not set root or stub hints");
1303                 worker_delete(worker);
1304                 return 0;
1305         }
1306         /* one probe timer per process -- if we have 5011 anchors */
1307         if(autr_get_num_anchors(worker->env.anchors) > 0
1308 #ifndef THREADS_DISABLED
1309                 && worker->thread_num == 0
1310 #endif
1311                 ) {
1312                 struct timeval tv;
1313                 tv.tv_sec = 0;
1314                 tv.tv_usec = 0;
1315                 worker->env.probe_timer = comm_timer_create(worker->base,
1316                         worker_probe_timer_cb, worker);
1317                 if(!worker->env.probe_timer) {
1318                         log_err("could not create 5011-probe timer");
1319                 } else {
1320                         /* let timer fire, then it can reset itself */
1321                         comm_timer_set(worker->env.probe_timer, &tv);
1322                 }
1323         }
1324         if(!worker->env.mesh || !worker->env.scratch_buffer) {
1325                 worker_delete(worker);
1326                 return 0;
1327         }
1328         worker_mem_report(worker, NULL);
1329         /* if statistics enabled start timer */
1330         if(worker->env.cfg->stat_interval > 0) {
1331                 verbose(VERB_ALGO, "set statistics interval %d secs",
1332                         worker->env.cfg->stat_interval);
1333                 worker_restart_timer(worker);
1334         }
1335         return 1;
1336 }
1337
1338 void
1339 worker_work(struct worker* worker)
1340 {
1341         comm_base_dispatch(worker->base);
1342 }
1343
1344 void
1345 worker_delete(struct worker* worker)
1346 {
1347         if(!worker)
1348                 return;
1349         if(worker->env.mesh && verbosity >= VERB_OPS) {
1350                 server_stats_log(&worker->stats, worker, worker->thread_num);
1351                 mesh_stats(worker->env.mesh, "mesh has");
1352                 worker_mem_report(worker, NULL);
1353         }
1354         outside_network_quit_prepare(worker->back);
1355         mesh_delete(worker->env.mesh);
1356         sldns_buffer_free(worker->env.scratch_buffer);
1357         forwards_delete(worker->env.fwds);
1358         hints_delete(worker->env.hints);
1359         listen_delete(worker->front);
1360         outside_network_delete(worker->back);
1361         comm_signal_delete(worker->comsig);
1362         tube_delete(worker->cmd);
1363         comm_timer_delete(worker->stat_timer);
1364         comm_timer_delete(worker->env.probe_timer);
1365         free(worker->ports);
1366         if(worker->thread_num == 0) {
1367                 log_set_time(NULL);
1368 #ifdef UB_ON_WINDOWS
1369                 wsvc_desetup_worker(worker);
1370 #endif /* UB_ON_WINDOWS */
1371         }
1372         comm_base_delete(worker->base);
1373         ub_randfree(worker->rndstate);
1374         alloc_clear(&worker->alloc);
1375         regional_destroy(worker->scratchpad);
1376         free(worker);
1377 }
1378
1379 struct outbound_entry*
1380 worker_send_query(uint8_t* qname, size_t qnamelen, uint16_t qtype,
1381         uint16_t qclass, uint16_t flags, int dnssec, int want_dnssec,
1382         int nocaps, struct edns_option* opt_list,
1383         struct sockaddr_storage* addr, socklen_t addrlen, uint8_t* zone,
1384         size_t zonelen, struct module_qstate* q)
1385 {
1386         struct worker* worker = q->env->worker;
1387         struct outbound_entry* e = (struct outbound_entry*)regional_alloc(
1388                 q->region, sizeof(*e));
1389         if(!e)
1390                 return NULL;
1391         e->qstate = q;
1392         e->qsent = outnet_serviced_query(worker->back, qname,
1393                 qnamelen, qtype, qclass, flags, dnssec, want_dnssec, nocaps,
1394                 q->env->cfg->tcp_upstream, q->env->cfg->ssl_upstream, opt_list,
1395                 addr, addrlen, zone, zonelen, worker_handle_service_reply, e,
1396                 worker->back->udp_buff);
1397         if(!e->qsent) {
1398                 return NULL;
1399         }
1400         return e;
1401 }
1402
1403 void
1404 worker_alloc_cleanup(void* arg)
1405 {
1406         struct worker* worker = (struct worker*)arg;
1407         slabhash_clear(&worker->env.rrset_cache->table);
1408         slabhash_clear(worker->env.msg_cache);
1409 }
1410
1411 void worker_stats_clear(struct worker* worker)
1412 {
1413         server_stats_init(&worker->stats, worker->env.cfg);
1414         mesh_stats_clear(worker->env.mesh);
1415         worker->back->unwanted_replies = 0;
1416         worker->back->num_tcp_outgoing = 0;
1417 }
1418
1419 void worker_start_accept(void* arg)
1420 {
1421         struct worker* worker = (struct worker*)arg;
1422         listen_start_accept(worker->front);
1423         if(worker->thread_num == 0)
1424                 daemon_remote_start_accept(worker->daemon->rc);
1425 }
1426
1427 void worker_stop_accept(void* arg)
1428 {
1429         struct worker* worker = (struct worker*)arg;
1430         listen_stop_accept(worker->front);
1431         if(worker->thread_num == 0)
1432                 daemon_remote_stop_accept(worker->daemon->rc);
1433 }
1434
1435 /* --- fake callbacks for fptr_wlist to work --- */
1436 struct outbound_entry* libworker_send_query(uint8_t* ATTR_UNUSED(qname),
1437         size_t ATTR_UNUSED(qnamelen), uint16_t ATTR_UNUSED(qtype),
1438         uint16_t ATTR_UNUSED(qclass), uint16_t ATTR_UNUSED(flags),
1439         int ATTR_UNUSED(dnssec), int ATTR_UNUSED(want_dnssec),
1440         int ATTR_UNUSED(nocaps), struct edns_option* ATTR_UNUSED(opt_list),
1441         struct sockaddr_storage* ATTR_UNUSED(addr),
1442         socklen_t ATTR_UNUSED(addrlen), uint8_t* ATTR_UNUSED(zone),
1443         size_t ATTR_UNUSED(zonelen), struct module_qstate* ATTR_UNUSED(q))
1444 {
1445         log_assert(0);
1446         return 0;
1447 }
1448
1449 int libworker_handle_reply(struct comm_point* ATTR_UNUSED(c),
1450         void* ATTR_UNUSED(arg), int ATTR_UNUSED(error),
1451         struct comm_reply* ATTR_UNUSED(reply_info))
1452 {
1453         log_assert(0);
1454         return 0;
1455 }
1456
1457 int libworker_handle_service_reply(struct comm_point* ATTR_UNUSED(c),
1458         void* ATTR_UNUSED(arg), int ATTR_UNUSED(error),
1459         struct comm_reply* ATTR_UNUSED(reply_info))
1460 {
1461         log_assert(0);
1462         return 0;
1463 }
1464
1465 void libworker_handle_control_cmd(struct tube* ATTR_UNUSED(tube),
1466         uint8_t* ATTR_UNUSED(buffer), size_t ATTR_UNUSED(len),
1467         int ATTR_UNUSED(error), void* ATTR_UNUSED(arg))
1468 {
1469         log_assert(0);
1470 }
1471
1472 void libworker_fg_done_cb(void* ATTR_UNUSED(arg), int ATTR_UNUSED(rcode),
1473         sldns_buffer* ATTR_UNUSED(buf), enum sec_status ATTR_UNUSED(s),
1474         char* ATTR_UNUSED(why_bogus))
1475 {
1476         log_assert(0);
1477 }
1478
1479 void libworker_bg_done_cb(void* ATTR_UNUSED(arg), int ATTR_UNUSED(rcode),
1480         sldns_buffer* ATTR_UNUSED(buf), enum sec_status ATTR_UNUSED(s),
1481         char* ATTR_UNUSED(why_bogus))
1482 {
1483         log_assert(0);
1484 }
1485
1486 void libworker_event_done_cb(void* ATTR_UNUSED(arg), int ATTR_UNUSED(rcode),
1487         sldns_buffer* ATTR_UNUSED(buf), enum sec_status ATTR_UNUSED(s),
1488         char* ATTR_UNUSED(why_bogus))
1489 {
1490         log_assert(0);
1491 }
1492
1493 int context_query_cmp(const void* ATTR_UNUSED(a), const void* ATTR_UNUSED(b))
1494 {
1495         log_assert(0);
1496         return 0;
1497 }
1498
1499 int order_lock_cmp(const void* ATTR_UNUSED(e1), const void* ATTR_UNUSED(e2))
1500 {
1501         log_assert(0);
1502         return 0;
1503 }
1504
1505 int codeline_cmp(const void* ATTR_UNUSED(a), const void* ATTR_UNUSED(b))
1506 {
1507         log_assert(0);
1508         return 0;
1509 }
1510