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/authzone.h"
62 #include "services/mesh.h"
63 #include "services/localzone.h"
64 #include "services/rpz.h"
65 #include "util/data/msgparse.h"
66 #include "util/data/msgencode.h"
67 #include "util/data/dname.h"
68 #include "util/fptr_wlist.h"
69 #include "util/proxy_protocol.h"
70 #include "util/tube.h"
71 #include "util/edns.h"
72 #include "util/timeval_func.h"
73 #include "iterator/iter_fwd.h"
74 #include "iterator/iter_hints.h"
75 #include "iterator/iter_utils.h"
76 #include "validator/autotrust.h"
77 #include "validator/val_anchor.h"
78 #include "respip/respip.h"
79 #include "libunbound/context.h"
80 #include "libunbound/libworker.h"
81 #include "sldns/sbuffer.h"
82 #include "sldns/wire2str.h"
83 #include "util/shm_side/shm_main.h"
84 #include "dnscrypt/dnscrypt.h"
85 #include "dnstap/dtstream.h"
86
87 #ifdef HAVE_SYS_TYPES_H
88 # include <sys/types.h>
89 #endif
90 #ifdef HAVE_NETDB_H
91 #include <netdb.h>
92 #endif
93 #include <signal.h>
94 #ifdef UB_ON_WINDOWS
95 #include "winrc/win_svc.h"
96 #endif
97
98 /** Size of an UDP datagram */
99 #define NORMAL_UDP_SIZE 512 /* bytes */
100 /** ratelimit for error responses */
101 #define ERROR_RATELIMIT 100 /* qps */
102
103 /**
104 * seconds to add to prefetch leeway. This is a TTL that expires old rrsets
105 * earlier than they should in order to put the new update into the cache.
106 * This additional value is to make sure that if not all TTLs are equal in
107 * the message to be updated(and replaced), that rrsets with up to this much
108 * extra TTL are also replaced. This means that the resulting new message
109 * will have (most likely) this TTL at least, avoiding very small 'split
110 * second' TTLs due to operators choosing relative primes for TTLs (or so).
111 * Also has to be at least one to break ties (and overwrite cached entry).
112 */
113 #define PREFETCH_EXPIRY_ADD 60
114
115 /** Report on memory usage by this thread and global */
116 static void
worker_mem_report(struct worker * ATTR_UNUSED (worker),struct serviced_query * ATTR_UNUSED (cur_serv))117 worker_mem_report(struct worker* ATTR_UNUSED(worker),
118 struct serviced_query* ATTR_UNUSED(cur_serv))
119 {
120 #ifdef UNBOUND_ALLOC_STATS
121 /* measure memory leakage */
122 extern size_t unbound_mem_alloc, unbound_mem_freed;
123 /* debug func in validator module */
124 size_t total, front, back, mesh, msg, rrset, infra, ac, superac;
125 size_t me, iter, val, anch;
126 int i;
127 #ifdef CLIENT_SUBNET
128 size_t subnet = 0;
129 #endif /* CLIENT_SUBNET */
130 if(verbosity < VERB_ALGO)
131 return;
132 front = listen_get_mem(worker->front);
133 back = outnet_get_mem(worker->back);
134 msg = slabhash_get_mem(worker->env.msg_cache);
135 rrset = slabhash_get_mem(&worker->env.rrset_cache->table);
136 infra = infra_get_mem(worker->env.infra_cache);
137 mesh = mesh_get_mem(worker->env.mesh);
138 ac = alloc_get_mem(worker->alloc);
139 superac = alloc_get_mem(&worker->daemon->superalloc);
140 anch = anchors_get_mem(worker->env.anchors);
141 iter = 0;
142 val = 0;
143 for(i=0; i<worker->env.mesh->mods.num; i++) {
144 fptr_ok(fptr_whitelist_mod_get_mem(worker->env.mesh->
145 mods.mod[i]->get_mem));
146 if(strcmp(worker->env.mesh->mods.mod[i]->name, "validator")==0)
147 val += (*worker->env.mesh->mods.mod[i]->get_mem)
148 (&worker->env, i);
149 #ifdef CLIENT_SUBNET
150 else if(strcmp(worker->env.mesh->mods.mod[i]->name,
151 "subnetcache")==0)
152 subnet += (*worker->env.mesh->mods.mod[i]->get_mem)
153 (&worker->env, i);
154 #endif /* CLIENT_SUBNET */
155 else iter += (*worker->env.mesh->mods.mod[i]->get_mem)
156 (&worker->env, i);
157 }
158 me = sizeof(*worker) + sizeof(*worker->base) + sizeof(*worker->comsig)
159 + comm_point_get_mem(worker->cmd_com)
160 + sizeof(worker->rndstate)
161 + regional_get_mem(worker->scratchpad)
162 + sizeof(*worker->env.scratch_buffer)
163 + sldns_buffer_capacity(worker->env.scratch_buffer)
164 + forwards_get_mem(worker->env.fwds)
165 + hints_get_mem(worker->env.hints);
166 if(worker->thread_num == 0)
167 me += acl_list_get_mem(worker->daemon->acl);
168 if(cur_serv) {
169 me += serviced_get_mem(cur_serv);
170 }
171 total = front+back+mesh+msg+rrset+infra+iter+val+ac+superac+me;
172 #ifdef CLIENT_SUBNET
173 total += subnet;
174 log_info("Memory conditions: %u front=%u back=%u mesh=%u msg=%u "
175 "rrset=%u infra=%u iter=%u val=%u subnet=%u anchors=%u "
176 "alloccache=%u globalalloccache=%u me=%u",
177 (unsigned)total, (unsigned)front, (unsigned)back,
178 (unsigned)mesh, (unsigned)msg, (unsigned)rrset, (unsigned)infra,
179 (unsigned)iter, (unsigned)val,
180 (unsigned)subnet, (unsigned)anch, (unsigned)ac,
181 (unsigned)superac, (unsigned)me);
182 #else /* no CLIENT_SUBNET */
183 log_info("Memory conditions: %u front=%u back=%u mesh=%u msg=%u "
184 "rrset=%u infra=%u iter=%u val=%u anchors=%u "
185 "alloccache=%u globalalloccache=%u me=%u",
186 (unsigned)total, (unsigned)front, (unsigned)back,
187 (unsigned)mesh, (unsigned)msg, (unsigned)rrset,
188 (unsigned)infra, (unsigned)iter, (unsigned)val, (unsigned)anch,
189 (unsigned)ac, (unsigned)superac, (unsigned)me);
190 #endif /* CLIENT_SUBNET */
191 log_info("Total heap memory estimate: %u total-alloc: %u "
192 "total-free: %u", (unsigned)total,
193 (unsigned)unbound_mem_alloc, (unsigned)unbound_mem_freed);
194 #else /* no UNBOUND_ALLOC_STATS */
195 size_t val = 0;
196 #ifdef CLIENT_SUBNET
197 size_t subnet = 0;
198 #endif /* CLIENT_SUBNET */
199 int i;
200 if(verbosity < VERB_QUERY)
201 return;
202 for(i=0; i<worker->env.mesh->mods.num; i++) {
203 fptr_ok(fptr_whitelist_mod_get_mem(worker->env.mesh->
204 mods.mod[i]->get_mem));
205 if(strcmp(worker->env.mesh->mods.mod[i]->name, "validator")==0)
206 val += (*worker->env.mesh->mods.mod[i]->get_mem)
207 (&worker->env, i);
208 #ifdef CLIENT_SUBNET
209 else if(strcmp(worker->env.mesh->mods.mod[i]->name,
210 "subnetcache")==0)
211 subnet += (*worker->env.mesh->mods.mod[i]->get_mem)
212 (&worker->env, i);
213 #endif /* CLIENT_SUBNET */
214 }
215 #ifdef CLIENT_SUBNET
216 verbose(VERB_QUERY, "cache memory msg=%u rrset=%u infra=%u val=%u "
217 "subnet=%u",
218 (unsigned)slabhash_get_mem(worker->env.msg_cache),
219 (unsigned)slabhash_get_mem(&worker->env.rrset_cache->table),
220 (unsigned)infra_get_mem(worker->env.infra_cache),
221 (unsigned)val, (unsigned)subnet);
222 #else /* no CLIENT_SUBNET */
223 verbose(VERB_QUERY, "cache memory msg=%u rrset=%u infra=%u val=%u",
224 (unsigned)slabhash_get_mem(worker->env.msg_cache),
225 (unsigned)slabhash_get_mem(&worker->env.rrset_cache->table),
226 (unsigned)infra_get_mem(worker->env.infra_cache),
227 (unsigned)val);
228 #endif /* CLIENT_SUBNET */
229 #endif /* UNBOUND_ALLOC_STATS */
230 }
231
232 void
worker_send_cmd(struct worker * worker,enum worker_commands cmd)233 worker_send_cmd(struct worker* worker, enum worker_commands cmd)
234 {
235 uint32_t c = (uint32_t)htonl(cmd);
236 if(!tube_write_msg(worker->cmd, (uint8_t*)&c, sizeof(c), 0)) {
237 log_err("worker send cmd %d failed", (int)cmd);
238 }
239 }
240
241 int
worker_handle_service_reply(struct comm_point * c,void * arg,int error,struct comm_reply * reply_info)242 worker_handle_service_reply(struct comm_point* c, void* arg, int error,
243 struct comm_reply* reply_info)
244 {
245 struct outbound_entry* e = (struct outbound_entry*)arg;
246 struct worker* worker = e->qstate->env->worker;
247 struct serviced_query *sq = e->qsent;
248
249 verbose(VERB_ALGO, "worker svcd callback for qstate %p", e->qstate);
250 if(error != 0) {
251 mesh_report_reply(worker->env.mesh, e, reply_info, error);
252 worker_mem_report(worker, sq);
253 return 0;
254 }
255 /* sanity check. */
256 if(!LDNS_QR_WIRE(sldns_buffer_begin(c->buffer))
257 || LDNS_OPCODE_WIRE(sldns_buffer_begin(c->buffer)) !=
258 LDNS_PACKET_QUERY
259 || LDNS_QDCOUNT(sldns_buffer_begin(c->buffer)) > 1) {
260 /* error becomes timeout for the module as if this reply
261 * never arrived. */
262 verbose(VERB_ALGO, "worker: bad reply handled as timeout");
263 mesh_report_reply(worker->env.mesh, e, reply_info,
264 NETEVENT_TIMEOUT);
265 worker_mem_report(worker, sq);
266 return 0;
267 }
268 mesh_report_reply(worker->env.mesh, e, reply_info, NETEVENT_NOERROR);
269 worker_mem_report(worker, sq);
270 return 0;
271 }
272
273 /** ratelimit error replies
274 * @param worker: the worker struct with ratelimit counter
275 * @param err: error code that would be wanted.
276 * @return value of err if okay, or -1 if it should be discarded instead.
277 */
278 static int
worker_err_ratelimit(struct worker * worker,int err)279 worker_err_ratelimit(struct worker* worker, int err)
280 {
281 if(worker->err_limit_time == *worker->env.now) {
282 /* see if limit is exceeded for this second */
283 if(worker->err_limit_count++ > ERROR_RATELIMIT)
284 return -1;
285 } else {
286 /* new second, new limits */
287 worker->err_limit_time = *worker->env.now;
288 worker->err_limit_count = 1;
289 }
290 return err;
291 }
292
293 /**
294 * Structure holding the result of the worker_check_request function.
295 * Based on configuration it could be called up to four times; ideally should
296 * be called once.
297 */
298 struct check_request_result {
299 int checked;
300 int value;
301 };
302 /** check request sanity.
303 * @param pkt: the wire packet to examine for sanity.
304 * @param worker: parameters for checking.
305 * @param out: struct to update with the result.
306 */
307 static void
worker_check_request(sldns_buffer * pkt,struct worker * worker,struct check_request_result * out)308 worker_check_request(sldns_buffer* pkt, struct worker* worker,
309 struct check_request_result* out)
310 {
311 if(out->checked) return;
312 out->checked = 1;
313 if(sldns_buffer_limit(pkt) < LDNS_HEADER_SIZE) {
314 verbose(VERB_QUERY, "request too short, discarded");
315 out->value = -1;
316 return;
317 }
318 if(sldns_buffer_limit(pkt) > NORMAL_UDP_SIZE &&
319 worker->daemon->cfg->harden_large_queries) {
320 verbose(VERB_QUERY, "request too large, discarded");
321 out->value = -1;
322 return;
323 }
324 if(LDNS_QR_WIRE(sldns_buffer_begin(pkt))) {
325 verbose(VERB_QUERY, "request has QR bit on, discarded");
326 out->value = -1;
327 return;
328 }
329 if(LDNS_TC_WIRE(sldns_buffer_begin(pkt))) {
330 LDNS_TC_CLR(sldns_buffer_begin(pkt));
331 verbose(VERB_QUERY, "request bad, has TC bit on");
332 out->value = worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
333 return;
334 }
335 if(LDNS_OPCODE_WIRE(sldns_buffer_begin(pkt)) != LDNS_PACKET_QUERY &&
336 LDNS_OPCODE_WIRE(sldns_buffer_begin(pkt)) != LDNS_PACKET_NOTIFY) {
337 verbose(VERB_QUERY, "request unknown opcode %d",
338 LDNS_OPCODE_WIRE(sldns_buffer_begin(pkt)));
339 out->value = worker_err_ratelimit(worker, LDNS_RCODE_NOTIMPL);
340 return;
341 }
342 if(LDNS_QDCOUNT(sldns_buffer_begin(pkt)) != 1) {
343 verbose(VERB_QUERY, "request wrong nr qd=%d",
344 LDNS_QDCOUNT(sldns_buffer_begin(pkt)));
345 out->value = worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
346 return;
347 }
348 if(LDNS_ANCOUNT(sldns_buffer_begin(pkt)) != 0 &&
349 (LDNS_ANCOUNT(sldns_buffer_begin(pkt)) != 1 ||
350 LDNS_OPCODE_WIRE(sldns_buffer_begin(pkt)) != LDNS_PACKET_NOTIFY)) {
351 verbose(VERB_QUERY, "request wrong nr an=%d",
352 LDNS_ANCOUNT(sldns_buffer_begin(pkt)));
353 out->value = worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
354 return;
355 }
356 if(LDNS_NSCOUNT(sldns_buffer_begin(pkt)) != 0) {
357 verbose(VERB_QUERY, "request wrong nr ns=%d",
358 LDNS_NSCOUNT(sldns_buffer_begin(pkt)));
359 out->value = worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
360 return;
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 out->value = worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
366 return;
367 }
368 out->value = 0;
369 return;
370 }
371
372 void
worker_handle_control_cmd(struct tube * ATTR_UNUSED (tube),uint8_t * msg,size_t len,int error,void * arg)373 worker_handle_control_cmd(struct tube* ATTR_UNUSED(tube), uint8_t* msg,
374 size_t len, int error, void* arg)
375 {
376 struct worker* worker = (struct worker*)arg;
377 enum worker_commands cmd;
378 if(error != NETEVENT_NOERROR) {
379 free(msg);
380 if(error == NETEVENT_CLOSED)
381 comm_base_exit(worker->base);
382 else log_info("control event: %d", error);
383 return;
384 }
385 if(len != sizeof(uint32_t)) {
386 fatal_exit("bad control msg length %d", (int)len);
387 }
388 cmd = sldns_read_uint32(msg);
389 free(msg);
390 switch(cmd) {
391 case worker_cmd_quit:
392 verbose(VERB_ALGO, "got control cmd quit");
393 comm_base_exit(worker->base);
394 break;
395 case worker_cmd_stats:
396 verbose(VERB_ALGO, "got control cmd stats");
397 server_stats_reply(worker, 1);
398 break;
399 case worker_cmd_stats_noreset:
400 verbose(VERB_ALGO, "got control cmd stats_noreset");
401 server_stats_reply(worker, 0);
402 break;
403 case worker_cmd_remote:
404 verbose(VERB_ALGO, "got control cmd remote");
405 daemon_remote_exec(worker);
406 break;
407 default:
408 log_err("bad command %d", (int)cmd);
409 break;
410 }
411 }
412
413 /** check if a delegation is secure */
414 static enum sec_status
check_delegation_secure(struct reply_info * rep)415 check_delegation_secure(struct reply_info *rep)
416 {
417 /* return smallest security status */
418 size_t i;
419 enum sec_status sec = sec_status_secure;
420 enum sec_status s;
421 size_t num = rep->an_numrrsets + rep->ns_numrrsets;
422 /* check if answer and authority are OK */
423 for(i=0; i<num; i++) {
424 s = ((struct packed_rrset_data*)rep->rrsets[i]->entry.data)
425 ->security;
426 if(s < sec)
427 sec = s;
428 }
429 /* in additional, only unchecked triggers revalidation */
430 for(i=num; i<rep->rrset_count; i++) {
431 s = ((struct packed_rrset_data*)rep->rrsets[i]->entry.data)
432 ->security;
433 if(s == sec_status_unchecked)
434 return s;
435 }
436 return sec;
437 }
438
439 /** remove nonsecure from a delegation referral additional section */
440 static void
deleg_remove_nonsecure_additional(struct reply_info * rep)441 deleg_remove_nonsecure_additional(struct reply_info* rep)
442 {
443 /* we can simply edit it, since we are working in the scratch region */
444 size_t i;
445 enum sec_status s;
446
447 for(i = rep->an_numrrsets+rep->ns_numrrsets; i<rep->rrset_count; i++) {
448 s = ((struct packed_rrset_data*)rep->rrsets[i]->entry.data)
449 ->security;
450 if(s != sec_status_secure) {
451 memmove(rep->rrsets+i, rep->rrsets+i+1,
452 sizeof(struct ub_packed_rrset_key*)*
453 (rep->rrset_count - i - 1));
454 rep->ar_numrrsets--;
455 rep->rrset_count--;
456 i--;
457 }
458 }
459 }
460
461 /** answer nonrecursive query from the cache */
462 static int
answer_norec_from_cache(struct worker * worker,struct query_info * qinfo,uint16_t id,uint16_t flags,struct comm_reply * repinfo,struct edns_data * edns)463 answer_norec_from_cache(struct worker* worker, struct query_info* qinfo,
464 uint16_t id, uint16_t flags, struct comm_reply* repinfo,
465 struct edns_data* edns)
466 {
467 /* for a nonrecursive query return either:
468 * o an error (servfail; we try to avoid this)
469 * o a delegation (closest we have; this routine tries that)
470 * o the answer (checked by answer_from_cache)
471 *
472 * So, grab a delegation from the rrset cache.
473 * Then check if it needs validation, if so, this routine fails,
474 * so that iterator can prime and validator can verify rrsets.
475 */
476 uint16_t udpsize = edns->udp_size;
477 int secure = 0;
478 time_t timenow = *worker->env.now;
479 int has_cd_bit = (flags&BIT_CD);
480 int must_validate = (!has_cd_bit || worker->env.cfg->ignore_cd)
481 && worker->env.need_to_validate;
482 struct dns_msg *msg = NULL;
483 struct delegpt *dp;
484
485 dp = dns_cache_find_delegation(&worker->env, qinfo->qname,
486 qinfo->qname_len, qinfo->qtype, qinfo->qclass,
487 worker->scratchpad, &msg, timenow, 0, NULL, 0);
488 if(!dp) { /* no delegation, need to reprime */
489 return 0;
490 }
491 /* In case we have a local alias, copy it into the delegation message.
492 * Shallow copy should be fine, as we'll be done with msg in this
493 * function. */
494 msg->qinfo.local_alias = qinfo->local_alias;
495 if(must_validate) {
496 switch(check_delegation_secure(msg->rep)) {
497 case sec_status_unchecked:
498 /* some rrsets have not been verified yet, go and
499 * let validator do that */
500 return 0;
501 case sec_status_bogus:
502 case sec_status_secure_sentinel_fail:
503 /* some rrsets are bogus, reply servfail */
504 edns->edns_version = EDNS_ADVERTISED_VERSION;
505 edns->udp_size = EDNS_ADVERTISED_SIZE;
506 edns->ext_rcode = 0;
507 edns->bits &= EDNS_DO;
508 if(!inplace_cb_reply_servfail_call(&worker->env, qinfo, NULL,
509 msg->rep, LDNS_RCODE_SERVFAIL, edns, repinfo, worker->scratchpad,
510 worker->env.now_tv))
511 return 0;
512 /* Attach the cached EDE (RFC8914) */
513 if(worker->env.cfg->ede &&
514 msg->rep->reason_bogus != LDNS_EDE_NONE) {
515 edns_opt_list_append_ede(&edns->opt_list_out,
516 worker->scratchpad, msg->rep->reason_bogus,
517 msg->rep->reason_bogus_str);
518 }
519 error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
520 &msg->qinfo, id, flags, edns);
521 if(worker->stats.extended) {
522 worker->stats.ans_bogus++;
523 worker->stats.ans_rcode[LDNS_RCODE_SERVFAIL]++;
524 }
525 return 1;
526 case sec_status_secure:
527 /* all rrsets are secure */
528 /* remove non-secure rrsets from the add. section*/
529 if(worker->env.cfg->val_clean_additional)
530 deleg_remove_nonsecure_additional(msg->rep);
531 secure = 1;
532 break;
533 case sec_status_indeterminate:
534 case sec_status_insecure:
535 default:
536 /* not secure */
537 secure = 0;
538 break;
539 }
540 }
541 /* return this delegation from the cache */
542 edns->edns_version = EDNS_ADVERTISED_VERSION;
543 edns->udp_size = EDNS_ADVERTISED_SIZE;
544 edns->ext_rcode = 0;
545 edns->bits &= EDNS_DO;
546 if(worker->env.cfg->disable_edns_do && (edns->bits & EDNS_DO))
547 edns->edns_present = 0;
548 if(!inplace_cb_reply_cache_call(&worker->env, qinfo, NULL, msg->rep,
549 (int)(flags&LDNS_RCODE_MASK), edns, repinfo, worker->scratchpad,
550 worker->env.now_tv))
551 return 0;
552 msg->rep->flags |= BIT_QR|BIT_RA;
553 /* Attach the cached EDE (RFC8914) if CD bit is set and the answer is
554 * bogus. */
555 if(worker->env.cfg->ede && has_cd_bit &&
556 (check_delegation_secure(msg->rep) == sec_status_bogus ||
557 check_delegation_secure(msg->rep) == sec_status_secure_sentinel_fail) &&
558 msg->rep->reason_bogus != LDNS_EDE_NONE) {
559 edns_opt_list_append_ede(&edns->opt_list_out,
560 worker->scratchpad, msg->rep->reason_bogus,
561 msg->rep->reason_bogus_str);
562 }
563 if(!reply_info_answer_encode(&msg->qinfo, msg->rep, id, flags,
564 repinfo->c->buffer, 0, 1, worker->scratchpad,
565 udpsize, edns, (int)(edns->bits & EDNS_DO), secure)) {
566 if(!inplace_cb_reply_servfail_call(&worker->env, qinfo, NULL, NULL,
567 LDNS_RCODE_SERVFAIL, edns, repinfo, worker->scratchpad,
568 worker->env.now_tv))
569 edns->opt_list_inplace_cb_out = NULL;
570 error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
571 &msg->qinfo, id, flags, edns);
572 }
573 if(worker->stats.extended) {
574 if(secure) worker->stats.ans_secure++;
575 server_stats_insrcode(&worker->stats, repinfo->c->buffer);
576 }
577 return 1;
578 }
579
580 /** Apply, if applicable, a response IP action to a cached answer.
581 * If the answer is rewritten as a result of an action, '*encode_repp' will
582 * point to the reply info containing the modified answer. '*encode_repp' will
583 * be intact otherwise.
584 * It returns 1 on success, 0 otherwise. */
585 static int
apply_respip_action(struct worker * worker,const struct query_info * qinfo,struct respip_client_info * cinfo,struct reply_info * rep,struct sockaddr_storage * addr,socklen_t addrlen,struct ub_packed_rrset_key ** alias_rrset,struct reply_info ** encode_repp,struct auth_zones * az)586 apply_respip_action(struct worker* worker, const struct query_info* qinfo,
587 struct respip_client_info* cinfo, struct reply_info* rep,
588 struct sockaddr_storage* addr, socklen_t addrlen,
589 struct ub_packed_rrset_key** alias_rrset,
590 struct reply_info** encode_repp, struct auth_zones* az)
591 {
592 struct respip_action_info actinfo = {0, 0, 0, 0, NULL, 0, NULL};
593 actinfo.action = respip_none;
594
595 if(qinfo->qtype != LDNS_RR_TYPE_A &&
596 qinfo->qtype != LDNS_RR_TYPE_AAAA &&
597 qinfo->qtype != LDNS_RR_TYPE_ANY)
598 return 1;
599
600 if(!respip_rewrite_reply(qinfo, cinfo, rep, encode_repp, &actinfo,
601 alias_rrset, 0, worker->scratchpad, az, NULL))
602 return 0;
603
604 /* xxx_deny actions mean dropping the reply, unless the original reply
605 * was redirected to response-ip data. */
606 if(actinfo.action == respip_always_deny ||
607 ((actinfo.action == respip_deny ||
608 actinfo.action == respip_inform_deny) &&
609 *encode_repp == rep))
610 *encode_repp = NULL;
611
612 /* If address info is returned, it means the action should be an
613 * 'inform' variant and the information should be logged. */
614 if(actinfo.addrinfo) {
615 respip_inform_print(&actinfo, qinfo->qname,
616 qinfo->qtype, qinfo->qclass, qinfo->local_alias,
617 addr, addrlen);
618
619 if(worker->stats.extended && actinfo.rpz_used) {
620 if(actinfo.rpz_disabled)
621 worker->stats.rpz_action[RPZ_DISABLED_ACTION]++;
622 if(actinfo.rpz_cname_override)
623 worker->stats.rpz_action[RPZ_CNAME_OVERRIDE_ACTION]++;
624 else
625 worker->stats.rpz_action[
626 respip_action_to_rpz_action(actinfo.action)]++;
627 }
628 }
629
630 return 1;
631 }
632
633 /** answer query from the cache.
634 * Normally, the answer message will be built in repinfo->c->buffer; if the
635 * answer is supposed to be suppressed or the answer is supposed to be an
636 * incomplete CNAME chain, the buffer is explicitly cleared to signal the
637 * caller as such. In the latter case *partial_rep will point to the incomplete
638 * reply, and this function is (possibly) supposed to be called again with that
639 * *partial_rep value to complete the chain. In addition, if the query should
640 * be completely dropped, '*need_drop' will be set to 1. */
641 static int
answer_from_cache(struct worker * worker,struct query_info * qinfo,struct respip_client_info * cinfo,int * need_drop,int * is_expired_answer,int * is_secure_answer,struct ub_packed_rrset_key ** alias_rrset,struct reply_info ** partial_repp,struct reply_info * rep,uint16_t id,uint16_t flags,struct comm_reply * repinfo,struct edns_data * edns)642 answer_from_cache(struct worker* worker, struct query_info* qinfo,
643 struct respip_client_info* cinfo, int* need_drop, int* is_expired_answer,
644 int* is_secure_answer, struct ub_packed_rrset_key** alias_rrset,
645 struct reply_info** partial_repp,
646 struct reply_info* rep, uint16_t id, uint16_t flags,
647 struct comm_reply* repinfo, struct edns_data* edns)
648 {
649 time_t timenow = *worker->env.now;
650 uint16_t udpsize = edns->udp_size;
651 struct reply_info* encode_rep = rep;
652 struct reply_info* partial_rep = *partial_repp;
653 int has_cd_bit = (flags&BIT_CD);
654 int must_validate = (!has_cd_bit || worker->env.cfg->ignore_cd)
655 && worker->env.need_to_validate;
656 *partial_repp = NULL; /* avoid accidental further pass */
657
658 /* Check TTL */
659 if(rep->ttl < timenow) {
660 /* Check if we need to serve expired now */
661 if(worker->env.cfg->serve_expired &&
662 !worker->env.cfg->serve_expired_client_timeout) {
663 if(worker->env.cfg->serve_expired_ttl &&
664 rep->serve_expired_ttl < timenow)
665 return 0;
666 /* Ignore expired failure answers */
667 if(FLAGS_GET_RCODE(rep->flags) !=
668 LDNS_RCODE_NOERROR &&
669 FLAGS_GET_RCODE(rep->flags) !=
670 LDNS_RCODE_NXDOMAIN &&
671 FLAGS_GET_RCODE(rep->flags) !=
672 LDNS_RCODE_YXDOMAIN)
673 return 0;
674 if(!rrset_array_lock(rep->ref, rep->rrset_count, 0))
675 return 0;
676 *is_expired_answer = 1;
677 } else {
678 /* the rrsets may have been updated in the meantime.
679 * we will refetch the message format from the
680 * authoritative server
681 */
682 return 0;
683 }
684 } else {
685 if(!rrset_array_lock(rep->ref, rep->rrset_count, timenow))
686 return 0;
687 }
688 /* locked and ids and ttls are OK. */
689
690 /* check CNAME chain (if any) */
691 if(rep->an_numrrsets > 0 && (rep->rrsets[0]->rk.type ==
692 htons(LDNS_RR_TYPE_CNAME) || rep->rrsets[0]->rk.type ==
693 htons(LDNS_RR_TYPE_DNAME))) {
694 if(!reply_check_cname_chain(qinfo, rep)) {
695 /* cname chain invalid, redo iterator steps */
696 verbose(VERB_ALGO, "Cache reply: cname chain broken");
697 goto bail_out;
698 }
699 }
700 /* check security status of the cached answer */
701 if(must_validate && (rep->security == sec_status_bogus ||
702 rep->security == sec_status_secure_sentinel_fail)) {
703 /* BAD cached */
704 edns->edns_version = EDNS_ADVERTISED_VERSION;
705 edns->udp_size = EDNS_ADVERTISED_SIZE;
706 edns->ext_rcode = 0;
707 edns->bits &= EDNS_DO;
708 if(worker->env.cfg->disable_edns_do && (edns->bits & EDNS_DO))
709 edns->edns_present = 0;
710 if(!inplace_cb_reply_servfail_call(&worker->env, qinfo, NULL, rep,
711 LDNS_RCODE_SERVFAIL, edns, repinfo, worker->scratchpad,
712 worker->env.now_tv))
713 goto bail_out;
714 /* Attach the cached EDE (RFC8914) */
715 if(worker->env.cfg->ede && rep->reason_bogus != LDNS_EDE_NONE) {
716 edns_opt_list_append_ede(&edns->opt_list_out,
717 worker->scratchpad, rep->reason_bogus,
718 rep->reason_bogus_str);
719 }
720 error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
721 qinfo, id, flags, edns);
722 rrset_array_unlock_touch(worker->env.rrset_cache,
723 worker->scratchpad, rep->ref, rep->rrset_count);
724 if(worker->stats.extended) {
725 worker->stats.ans_bogus ++;
726 worker->stats.ans_rcode[LDNS_RCODE_SERVFAIL] ++;
727 }
728 return 1;
729 } else if(rep->security == sec_status_unchecked && must_validate) {
730 verbose(VERB_ALGO, "Cache reply: unchecked entry needs "
731 "validation");
732 goto bail_out; /* need to validate cache entry first */
733 } else if(rep->security == sec_status_secure) {
734 if(reply_all_rrsets_secure(rep)) {
735 *is_secure_answer = 1;
736 } else {
737 if(must_validate) {
738 verbose(VERB_ALGO, "Cache reply: secure entry"
739 " changed status");
740 goto bail_out; /* rrset changed, re-verify */
741 }
742 *is_secure_answer = 0;
743 }
744 } else *is_secure_answer = 0;
745
746 edns->edns_version = EDNS_ADVERTISED_VERSION;
747 edns->udp_size = EDNS_ADVERTISED_SIZE;
748 edns->ext_rcode = 0;
749 edns->bits &= EDNS_DO;
750 if(worker->env.cfg->disable_edns_do && (edns->bits & EDNS_DO))
751 edns->edns_present = 0;
752 *alias_rrset = NULL; /* avoid confusion if caller set it to non-NULL */
753 if((worker->daemon->use_response_ip || worker->daemon->use_rpz) &&
754 !partial_rep && !apply_respip_action(worker, qinfo, cinfo, rep,
755 &repinfo->client_addr, repinfo->client_addrlen, alias_rrset,
756 &encode_rep, worker->env.auth_zones)) {
757 goto bail_out;
758 } else if(partial_rep &&
759 !respip_merge_cname(partial_rep, qinfo, rep, cinfo,
760 must_validate, &encode_rep, worker->scratchpad,
761 worker->env.auth_zones)) {
762 goto bail_out;
763 }
764 if(encode_rep != rep) {
765 /* if rewritten, it can't be considered "secure" */
766 *is_secure_answer = 0;
767 }
768 if(!encode_rep || *alias_rrset) {
769 if(!encode_rep)
770 *need_drop = 1;
771 else {
772 /* If a partial CNAME chain is found, we first need to
773 * make a copy of the reply in the scratchpad so we
774 * can release the locks and lookup the cache again. */
775 *partial_repp = reply_info_copy(encode_rep, NULL,
776 worker->scratchpad);
777 if(!*partial_repp)
778 goto bail_out;
779 }
780 } else {
781 if(*is_expired_answer == 1 &&
782 worker->env.cfg->ede_serve_expired && worker->env.cfg->ede) {
783 EDNS_OPT_LIST_APPEND_EDE(&edns->opt_list_out,
784 worker->scratchpad, LDNS_EDE_STALE_ANSWER, "");
785 }
786 /* Attach the cached EDE (RFC8914) if CD bit is set and the
787 * answer is bogus. */
788 if(*is_secure_answer == 0 &&
789 worker->env.cfg->ede && has_cd_bit &&
790 encode_rep->reason_bogus != LDNS_EDE_NONE) {
791 edns_opt_list_append_ede(&edns->opt_list_out,
792 worker->scratchpad, encode_rep->reason_bogus,
793 encode_rep->reason_bogus_str);
794 }
795 if(!inplace_cb_reply_cache_call(&worker->env, qinfo, NULL, encode_rep,
796 (int)(flags&LDNS_RCODE_MASK), edns, repinfo, worker->scratchpad,
797 worker->env.now_tv))
798 goto bail_out;
799 if(!reply_info_answer_encode(qinfo, encode_rep, id, flags,
800 repinfo->c->buffer, timenow, 1, worker->scratchpad,
801 udpsize, edns, (int)(edns->bits & EDNS_DO),
802 *is_secure_answer)) {
803 if(!inplace_cb_reply_servfail_call(&worker->env, qinfo,
804 NULL, NULL, LDNS_RCODE_SERVFAIL, edns, repinfo,
805 worker->scratchpad, worker->env.now_tv))
806 edns->opt_list_inplace_cb_out = NULL;
807 error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
808 qinfo, id, flags, edns);
809 }
810 }
811 /* cannot send the reply right now, because blocking network syscall
812 * is bad while holding locks. */
813 rrset_array_unlock_touch(worker->env.rrset_cache, worker->scratchpad,
814 rep->ref, rep->rrset_count);
815 /* go and return this buffer to the client */
816 return 1;
817
818 bail_out:
819 rrset_array_unlock_touch(worker->env.rrset_cache,
820 worker->scratchpad, rep->ref, rep->rrset_count);
821 return 0;
822 }
823
824 /** Reply to client and perform prefetch to keep cache up to date. */
825 static void
reply_and_prefetch(struct worker * worker,struct query_info * qinfo,uint16_t flags,struct comm_reply * repinfo,time_t leeway,int noreply,int rpz_passthru,struct edns_option * opt_list)826 reply_and_prefetch(struct worker* worker, struct query_info* qinfo,
827 uint16_t flags, struct comm_reply* repinfo, time_t leeway, int noreply,
828 int rpz_passthru, struct edns_option* opt_list)
829 {
830 (void)opt_list;
831 /* first send answer to client to keep its latency
832 * as small as a cachereply */
833 if(!noreply) {
834 if(repinfo->c->tcp_req_info) {
835 sldns_buffer_copy(
836 repinfo->c->tcp_req_info->spool_buffer,
837 repinfo->c->buffer);
838 }
839 comm_point_send_reply(repinfo);
840 }
841 server_stats_prefetch(&worker->stats, worker);
842 #ifdef CLIENT_SUBNET
843 /* Check if the subnet module is enabled. In that case pass over the
844 * comm_reply information for ECS generation later. The mesh states are
845 * unique when subnet is enabled. */
846 if(modstack_find(&worker->env.mesh->mods, "subnetcache") != -1
847 && worker->env.unique_mesh) {
848 mesh_new_prefetch(worker->env.mesh, qinfo, flags, leeway +
849 PREFETCH_EXPIRY_ADD, rpz_passthru,
850 &repinfo->client_addr, opt_list);
851 return;
852 }
853 #endif
854 /* create the prefetch in the mesh as a normal lookup without
855 * client addrs waiting, which has the cache blacklisted (to bypass
856 * the cache and go to the network for the data). */
857 /* this (potentially) runs the mesh for the new query */
858 mesh_new_prefetch(worker->env.mesh, qinfo, flags, leeway +
859 PREFETCH_EXPIRY_ADD, rpz_passthru, NULL, NULL);
860 }
861
862 /**
863 * Fill CH class answer into buffer. Keeps query.
864 * @param pkt: buffer
865 * @param str: string to put into text record (<255).
866 * array of strings, every string becomes a text record.
867 * @param num: number of strings in array.
868 * @param edns: edns reply information.
869 * @param worker: worker with scratch region.
870 * @param repinfo: reply information for a communication point.
871 */
872 static void
chaos_replystr(sldns_buffer * pkt,char ** str,int num,struct edns_data * edns,struct worker * worker,struct comm_reply * repinfo)873 chaos_replystr(sldns_buffer* pkt, char** str, int num, struct edns_data* edns,
874 struct worker* worker, struct comm_reply* repinfo)
875 {
876 int i;
877 unsigned int rd = LDNS_RD_WIRE(sldns_buffer_begin(pkt));
878 unsigned int cd = LDNS_CD_WIRE(sldns_buffer_begin(pkt));
879 size_t udpsize = edns->udp_size;
880 edns->edns_version = EDNS_ADVERTISED_VERSION;
881 edns->udp_size = EDNS_ADVERTISED_SIZE;
882 edns->bits &= EDNS_DO;
883 if(!inplace_cb_reply_local_call(&worker->env, NULL, NULL, NULL,
884 LDNS_RCODE_NOERROR, edns, repinfo, worker->scratchpad,
885 worker->env.now_tv))
886 edns->opt_list_inplace_cb_out = NULL;
887 sldns_buffer_clear(pkt);
888 sldns_buffer_skip(pkt, (ssize_t)sizeof(uint16_t)); /* skip id */
889 sldns_buffer_write_u16(pkt, (uint16_t)(BIT_QR|BIT_RA));
890 if(rd) LDNS_RD_SET(sldns_buffer_begin(pkt));
891 if(cd) LDNS_CD_SET(sldns_buffer_begin(pkt));
892 sldns_buffer_write_u16(pkt, 1); /* qdcount */
893 sldns_buffer_write_u16(pkt, (uint16_t)num); /* ancount */
894 sldns_buffer_write_u16(pkt, 0); /* nscount */
895 sldns_buffer_write_u16(pkt, 0); /* arcount */
896 (void)query_dname_len(pkt); /* skip qname */
897 sldns_buffer_skip(pkt, (ssize_t)sizeof(uint16_t)); /* skip qtype */
898 sldns_buffer_skip(pkt, (ssize_t)sizeof(uint16_t)); /* skip qclass */
899 for(i=0; i<num; i++) {
900 size_t len = strlen(str[i]);
901 if(len>255) len=255; /* cap size of TXT record */
902 if(sldns_buffer_position(pkt)+2+2+2+4+2+1+len+
903 calc_edns_field_size(edns) > udpsize) {
904 sldns_buffer_write_u16_at(pkt, 6, i); /* ANCOUNT */
905 LDNS_TC_SET(sldns_buffer_begin(pkt));
906 break;
907 }
908 sldns_buffer_write_u16(pkt, 0xc00c); /* compr ptr to query */
909 sldns_buffer_write_u16(pkt, LDNS_RR_TYPE_TXT);
910 sldns_buffer_write_u16(pkt, LDNS_RR_CLASS_CH);
911 sldns_buffer_write_u32(pkt, 0); /* TTL */
912 sldns_buffer_write_u16(pkt, sizeof(uint8_t) + len);
913 sldns_buffer_write_u8(pkt, len);
914 sldns_buffer_write(pkt, str[i], len);
915 }
916 sldns_buffer_flip(pkt);
917 if(sldns_buffer_capacity(pkt) >=
918 sldns_buffer_limit(pkt)+calc_edns_field_size(edns))
919 attach_edns_record(pkt, edns);
920 }
921
922 /** Reply with one string */
923 static void
chaos_replyonestr(sldns_buffer * pkt,const char * str,struct edns_data * edns,struct worker * worker,struct comm_reply * repinfo)924 chaos_replyonestr(sldns_buffer* pkt, const char* str, struct edns_data* edns,
925 struct worker* worker, struct comm_reply* repinfo)
926 {
927 chaos_replystr(pkt, (char**)&str, 1, edns, worker, repinfo);
928 }
929
930 /**
931 * Create CH class trustanchor answer.
932 * @param pkt: buffer
933 * @param edns: edns reply information.
934 * @param w: worker with scratch region.
935 * @param repinfo: reply information for a communication point.
936 */
937 static void
chaos_trustanchor(sldns_buffer * pkt,struct edns_data * edns,struct worker * w,struct comm_reply * repinfo)938 chaos_trustanchor(sldns_buffer* pkt, struct edns_data* edns, struct worker* w,
939 struct comm_reply* repinfo)
940 {
941 #define TA_RESPONSE_MAX_TXT 16 /* max number of TXT records */
942 #define TA_RESPONSE_MAX_TAGS 32 /* max number of tags printed per zone */
943 char* str_array[TA_RESPONSE_MAX_TXT];
944 uint16_t tags[TA_RESPONSE_MAX_TAGS];
945 int num = 0;
946 struct trust_anchor* ta;
947
948 if(!w->env.need_to_validate) {
949 /* no validator module, reply no trustanchors */
950 chaos_replystr(pkt, NULL, 0, edns, w, repinfo);
951 return;
952 }
953
954 /* fill the string with contents */
955 lock_basic_lock(&w->env.anchors->lock);
956 RBTREE_FOR(ta, struct trust_anchor*, w->env.anchors->tree) {
957 char* str;
958 size_t i, numtag, str_len = 255;
959 if(num == TA_RESPONSE_MAX_TXT) continue;
960 str = (char*)regional_alloc(w->scratchpad, str_len);
961 if(!str) continue;
962 lock_basic_lock(&ta->lock);
963 numtag = anchor_list_keytags(ta, tags, TA_RESPONSE_MAX_TAGS);
964 if(numtag == 0) {
965 /* empty, insecure point */
966 lock_basic_unlock(&ta->lock);
967 continue;
968 }
969 str_array[num] = str;
970 num++;
971
972 /* spool name of anchor */
973 (void)sldns_wire2str_dname_buf(ta->name, ta->namelen, str, str_len);
974 str_len -= strlen(str); str += strlen(str);
975 /* spool tags */
976 for(i=0; i<numtag; i++) {
977 snprintf(str, str_len, " %u", (unsigned)tags[i]);
978 str_len -= strlen(str); str += strlen(str);
979 }
980 lock_basic_unlock(&ta->lock);
981 }
982 lock_basic_unlock(&w->env.anchors->lock);
983
984 chaos_replystr(pkt, str_array, num, edns, w, repinfo);
985 regional_free_all(w->scratchpad);
986 }
987
988 /**
989 * Answer CH class queries.
990 * @param w: worker
991 * @param qinfo: query info. Pointer into packet buffer.
992 * @param edns: edns info from query.
993 * @param repinfo: reply information for a communication point.
994 * @param pkt: packet buffer.
995 * @return: true if a reply is to be sent.
996 */
997 static int
answer_chaos(struct worker * w,struct query_info * qinfo,struct edns_data * edns,struct comm_reply * repinfo,sldns_buffer * pkt)998 answer_chaos(struct worker* w, struct query_info* qinfo,
999 struct edns_data* edns, struct comm_reply* repinfo, sldns_buffer* pkt)
1000 {
1001 struct config_file* cfg = w->env.cfg;
1002 if(qinfo->qtype != LDNS_RR_TYPE_ANY && qinfo->qtype != LDNS_RR_TYPE_TXT)
1003 return 0;
1004 if(query_dname_compare(qinfo->qname,
1005 (uint8_t*)"\002id\006server") == 0 ||
1006 query_dname_compare(qinfo->qname,
1007 (uint8_t*)"\010hostname\004bind") == 0)
1008 {
1009 if(cfg->hide_identity)
1010 return 0;
1011 if(cfg->identity==NULL || cfg->identity[0]==0) {
1012 char buf[MAXHOSTNAMELEN+1];
1013 if (gethostname(buf, MAXHOSTNAMELEN) == 0) {
1014 buf[MAXHOSTNAMELEN] = 0;
1015 chaos_replyonestr(pkt, buf, edns, w, repinfo);
1016 } else {
1017 log_err("gethostname: %s", strerror(errno));
1018 chaos_replyonestr(pkt, "no hostname", edns, w, repinfo);
1019 }
1020 }
1021 else chaos_replyonestr(pkt, cfg->identity, edns, w, repinfo);
1022 return 1;
1023 }
1024 if(query_dname_compare(qinfo->qname,
1025 (uint8_t*)"\007version\006server") == 0 ||
1026 query_dname_compare(qinfo->qname,
1027 (uint8_t*)"\007version\004bind") == 0)
1028 {
1029 if(cfg->hide_version)
1030 return 0;
1031 if(cfg->version==NULL || cfg->version[0]==0)
1032 chaos_replyonestr(pkt, PACKAGE_STRING, edns, w, repinfo);
1033 else chaos_replyonestr(pkt, cfg->version, edns, w, repinfo);
1034 return 1;
1035 }
1036 if(query_dname_compare(qinfo->qname,
1037 (uint8_t*)"\013trustanchor\007unbound") == 0)
1038 {
1039 if(cfg->hide_trustanchor)
1040 return 0;
1041 chaos_trustanchor(pkt, edns, w, repinfo);
1042 return 1;
1043 }
1044
1045 return 0;
1046 }
1047
1048 /**
1049 * Answer notify queries. These are notifies for authoritative zones,
1050 * the reply is an ack that the notify has been received. We need to check
1051 * access permission here.
1052 * @param w: worker
1053 * @param qinfo: query info. Pointer into packet buffer.
1054 * @param edns: edns info from query.
1055 * @param addr: client address.
1056 * @param addrlen: client address length.
1057 * @param pkt: packet buffer.
1058 */
1059 static void
answer_notify(struct worker * w,struct query_info * qinfo,struct edns_data * edns,sldns_buffer * pkt,struct sockaddr_storage * addr,socklen_t addrlen)1060 answer_notify(struct worker* w, struct query_info* qinfo,
1061 struct edns_data* edns, sldns_buffer* pkt,
1062 struct sockaddr_storage* addr, socklen_t addrlen)
1063 {
1064 int refused = 0;
1065 int rcode = LDNS_RCODE_NOERROR;
1066 uint32_t serial = 0;
1067 int has_serial;
1068 if(!w->env.auth_zones) return;
1069 has_serial = auth_zone_parse_notify_serial(pkt, &serial);
1070 if(auth_zones_notify(w->env.auth_zones, &w->env, qinfo->qname,
1071 qinfo->qname_len, qinfo->qclass, addr,
1072 addrlen, has_serial, serial, &refused)) {
1073 rcode = LDNS_RCODE_NOERROR;
1074 } else {
1075 if(refused)
1076 rcode = LDNS_RCODE_REFUSED;
1077 else rcode = LDNS_RCODE_SERVFAIL;
1078 }
1079
1080 if(verbosity >= VERB_DETAIL) {
1081 char buf[380];
1082 char zname[255+1];
1083 char sr[25];
1084 dname_str(qinfo->qname, zname);
1085 sr[0]=0;
1086 if(has_serial)
1087 snprintf(sr, sizeof(sr), "serial %u ",
1088 (unsigned)serial);
1089 if(rcode == LDNS_RCODE_REFUSED)
1090 snprintf(buf, sizeof(buf),
1091 "refused NOTIFY %sfor %s from", sr, zname);
1092 else if(rcode == LDNS_RCODE_SERVFAIL)
1093 snprintf(buf, sizeof(buf),
1094 "servfail for NOTIFY %sfor %s from", sr, zname);
1095 else snprintf(buf, sizeof(buf),
1096 "received NOTIFY %sfor %s from", sr, zname);
1097 log_addr(VERB_DETAIL, buf, addr, addrlen);
1098 }
1099 edns->edns_version = EDNS_ADVERTISED_VERSION;
1100 edns->udp_size = EDNS_ADVERTISED_SIZE;
1101 edns->ext_rcode = 0;
1102 edns->bits &= EDNS_DO;
1103 error_encode(pkt, rcode, qinfo,
1104 *(uint16_t*)(void *)sldns_buffer_begin(pkt),
1105 sldns_buffer_read_u16_at(pkt, 2), edns);
1106 LDNS_OPCODE_SET(sldns_buffer_begin(pkt), LDNS_PACKET_NOTIFY);
1107 }
1108
1109 static int
deny_refuse(struct comm_point * c,enum acl_access acl,enum acl_access deny,enum acl_access refuse,struct worker * worker,struct comm_reply * repinfo,struct acl_addr * acladdr,int ede,struct check_request_result * check_result)1110 deny_refuse(struct comm_point* c, enum acl_access acl,
1111 enum acl_access deny, enum acl_access refuse,
1112 struct worker* worker, struct comm_reply* repinfo,
1113 struct acl_addr* acladdr, int ede,
1114 struct check_request_result* check_result)
1115 {
1116 if(acl == deny) {
1117 if(verbosity >= VERB_ALGO) {
1118 log_acl_action("dropped", &repinfo->client_addr,
1119 repinfo->client_addrlen, acl, acladdr);
1120 log_buf(VERB_ALGO, "dropped", c->buffer);
1121 }
1122 comm_point_drop_reply(repinfo);
1123 if(worker->stats.extended)
1124 worker->stats.unwanted_queries++;
1125 return 0;
1126 } else if(acl == refuse) {
1127 size_t opt_rr_mark;
1128
1129 if(verbosity >= VERB_ALGO) {
1130 log_acl_action("refused", &repinfo->client_addr,
1131 repinfo->client_addrlen, acl, acladdr);
1132 log_buf(VERB_ALGO, "refuse", c->buffer);
1133 }
1134
1135 if(worker->stats.extended)
1136 worker->stats.unwanted_queries++;
1137 worker_check_request(c->buffer, worker, check_result);
1138 if(check_result->value != 0) {
1139 if(check_result->value != -1) {
1140 LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1141 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1142 check_result->value);
1143 return 1;
1144 }
1145 comm_point_drop_reply(repinfo);
1146 return 0;
1147 }
1148 /* worker_check_request() above guarantees that the buffer contains at
1149 * least a header and that qdcount == 1
1150 */
1151 log_assert(sldns_buffer_limit(c->buffer) >= LDNS_HEADER_SIZE
1152 && LDNS_QDCOUNT(sldns_buffer_begin(c->buffer)) == 1);
1153
1154 sldns_buffer_skip(c->buffer, LDNS_HEADER_SIZE); /* skip header */
1155
1156 /* check additional section is present and that we respond with EDEs */
1157 if(LDNS_ARCOUNT(sldns_buffer_begin(c->buffer)) != 1
1158 || !ede) {
1159 LDNS_QDCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1160 LDNS_ANCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1161 LDNS_NSCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1162 LDNS_ARCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1163 LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1164 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1165 LDNS_RCODE_REFUSED);
1166 sldns_buffer_flip(c->buffer);
1167 return 1;
1168 }
1169
1170 if (!query_dname_len(c->buffer)) {
1171 LDNS_QDCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1172 LDNS_ANCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1173 LDNS_NSCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1174 LDNS_ARCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1175 LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1176 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1177 LDNS_RCODE_FORMERR);
1178 sldns_buffer_set_position(c->buffer, LDNS_HEADER_SIZE);
1179 sldns_buffer_flip(c->buffer);
1180 return 1;
1181 }
1182 /* space available for query type and class? */
1183 if (sldns_buffer_remaining(c->buffer) < 2 * sizeof(uint16_t)) {
1184 LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1185 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1186 LDNS_RCODE_FORMERR);
1187 LDNS_QDCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1188 LDNS_ANCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1189 LDNS_NSCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1190 LDNS_ARCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1191 sldns_buffer_set_position(c->buffer, LDNS_HEADER_SIZE);
1192 sldns_buffer_flip(c->buffer);
1193 return 1;
1194 }
1195 LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1196 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1197 LDNS_RCODE_REFUSED);
1198
1199 sldns_buffer_skip(c->buffer, (ssize_t)sizeof(uint16_t)); /* skip qtype */
1200
1201 sldns_buffer_skip(c->buffer, (ssize_t)sizeof(uint16_t)); /* skip qclass */
1202
1203 /* The OPT RR to be returned should come directly after
1204 * the query, so mark this spot.
1205 */
1206 opt_rr_mark = sldns_buffer_position(c->buffer);
1207
1208 /* Skip through the RR records */
1209 if(LDNS_ANCOUNT(sldns_buffer_begin(c->buffer)) != 0 ||
1210 LDNS_NSCOUNT(sldns_buffer_begin(c->buffer)) != 0) {
1211 if(!skip_pkt_rrs(c->buffer,
1212 ((int)LDNS_ANCOUNT(sldns_buffer_begin(c->buffer)))+
1213 ((int)LDNS_NSCOUNT(sldns_buffer_begin(c->buffer))))) {
1214 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1215 LDNS_RCODE_FORMERR);
1216 LDNS_ANCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1217 LDNS_NSCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1218 LDNS_ARCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1219 sldns_buffer_set_position(c->buffer, opt_rr_mark);
1220 sldns_buffer_flip(c->buffer);
1221 return 1;
1222 }
1223 }
1224 /* Do we have a valid OPT RR here? If not return REFUSED (could be a valid TSIG or something so no FORMERR) */
1225 /* domain name must be the root of length 1. */
1226 if(sldns_buffer_remaining(c->buffer) < 1 || *sldns_buffer_current(c->buffer) != 0) {
1227 LDNS_ANCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1228 LDNS_NSCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1229 LDNS_ARCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1230 sldns_buffer_set_position(c->buffer, opt_rr_mark);
1231 sldns_buffer_flip(c->buffer);
1232 return 1;
1233 } else {
1234 sldns_buffer_skip(c->buffer, 1); /* skip root label */
1235 }
1236 if(sldns_buffer_remaining(c->buffer) < 2 ||
1237 sldns_buffer_read_u16(c->buffer) != LDNS_RR_TYPE_OPT) {
1238 LDNS_ANCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1239 LDNS_NSCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1240 LDNS_ARCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1241 sldns_buffer_set_position(c->buffer, opt_rr_mark);
1242 sldns_buffer_flip(c->buffer);
1243 return 1;
1244 }
1245 /* Write OPT RR directly after the query,
1246 * so without the (possibly skipped) Answer and NS RRs
1247 */
1248 LDNS_ANCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1249 LDNS_NSCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1250 sldns_buffer_clear(c->buffer); /* reset write limit */
1251 sldns_buffer_set_position(c->buffer, opt_rr_mark);
1252
1253 /* Check if OPT record can be written
1254 * 17 == root label (1) + RR type (2) + UDP Size (2)
1255 * + Fields (4) + rdata len (2) + EDE Option code (2)
1256 * + EDE Option length (2) + EDE info-code (2)
1257 */
1258 if (sldns_buffer_available(c->buffer, 17) == 0) {
1259 LDNS_ARCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1260 sldns_buffer_flip(c->buffer);
1261 return 1;
1262 }
1263
1264 LDNS_ARCOUNT_SET(sldns_buffer_begin(c->buffer), 1);
1265
1266 /* root label */
1267 sldns_buffer_write_u8(c->buffer, 0);
1268 sldns_buffer_write_u16(c->buffer, LDNS_RR_TYPE_OPT);
1269 sldns_buffer_write_u16(c->buffer, EDNS_ADVERTISED_SIZE);
1270
1271 /* write OPT Record TTL Field */
1272 sldns_buffer_write_u32(c->buffer, 0);
1273
1274 /* write rdata len: EDE option + length + info-code */
1275 sldns_buffer_write_u16(c->buffer, 6);
1276
1277 /* write OPTIONS; add EDE option code */
1278 sldns_buffer_write_u16(c->buffer, LDNS_EDNS_EDE);
1279
1280 /* write single EDE option length (for just 1 info-code) */
1281 sldns_buffer_write_u16(c->buffer, 2);
1282
1283 /* write single EDE info-code */
1284 sldns_buffer_write_u16(c->buffer, LDNS_EDE_PROHIBITED);
1285
1286 sldns_buffer_flip(c->buffer);
1287
1288 verbose(VERB_ALGO, "attached EDE code: %d", LDNS_EDE_PROHIBITED);
1289
1290 return 1;
1291
1292 }
1293
1294 return -1;
1295 }
1296
1297 static int
deny_refuse_all(struct comm_point * c,enum acl_access * acl,struct worker * worker,struct comm_reply * repinfo,struct acl_addr ** acladdr,int ede,int check_proxy,struct check_request_result * check_result)1298 deny_refuse_all(struct comm_point* c, enum acl_access* acl,
1299 struct worker* worker, struct comm_reply* repinfo,
1300 struct acl_addr** acladdr, int ede, int check_proxy,
1301 struct check_request_result* check_result)
1302 {
1303 if(check_proxy) {
1304 *acladdr = acl_addr_lookup(worker->daemon->acl,
1305 &repinfo->remote_addr, repinfo->remote_addrlen);
1306 } else {
1307 *acladdr = acl_addr_lookup(worker->daemon->acl,
1308 &repinfo->client_addr, repinfo->client_addrlen);
1309 }
1310 /* If there is no ACL based on client IP use the interface ACL. */
1311 if(!(*acladdr) && c->socket) {
1312 *acladdr = c->socket->acl;
1313 }
1314 *acl = acl_get_control(*acladdr);
1315 return deny_refuse(c, *acl, acl_deny, acl_refuse, worker, repinfo,
1316 *acladdr, ede, check_result);
1317 }
1318
1319 static int
deny_refuse_non_local(struct comm_point * c,enum acl_access acl,struct worker * worker,struct comm_reply * repinfo,struct acl_addr * acladdr,int ede,struct check_request_result * check_result)1320 deny_refuse_non_local(struct comm_point* c, enum acl_access acl,
1321 struct worker* worker, struct comm_reply* repinfo,
1322 struct acl_addr* acladdr, int ede,
1323 struct check_request_result* check_result)
1324 {
1325 return deny_refuse(c, acl, acl_deny_non_local, acl_refuse_non_local,
1326 worker, repinfo, acladdr, ede, check_result);
1327 }
1328
1329 /* Returns 1 if the ip rate limit check can happen before EDNS parsing,
1330 * else 0 */
1331 static int
pre_edns_ip_ratelimit_check(enum acl_access acl)1332 pre_edns_ip_ratelimit_check(enum acl_access acl)
1333 {
1334 if(acl == acl_allow_cookie) return 0;
1335 return 1;
1336 }
1337
1338 /* Check if the query is blocked by source IP rate limiting.
1339 * Returns 1 if it passes the check, 0 otherwise. */
1340 static int
check_ip_ratelimit(struct worker * worker,struct sockaddr_storage * addr,socklen_t addrlen,int has_cookie,sldns_buffer * pkt)1341 check_ip_ratelimit(struct worker* worker, struct sockaddr_storage* addr,
1342 socklen_t addrlen, int has_cookie, sldns_buffer* pkt)
1343 {
1344 if(!infra_ip_ratelimit_inc(worker->env.infra_cache, addr, addrlen,
1345 *worker->env.now, has_cookie,
1346 worker->env.cfg->ip_ratelimit_backoff, pkt)) {
1347 /* See if we can pass through with slip factor */
1348 if(!has_cookie && worker->env.cfg->ip_ratelimit_factor != 0 &&
1349 ub_random_max(worker->env.rnd,
1350 worker->env.cfg->ip_ratelimit_factor) == 0) {
1351 char addrbuf[128];
1352 addr_to_str(addr, addrlen, addrbuf, sizeof(addrbuf));
1353 verbose(VERB_QUERY, "ip_ratelimit allowed through for "
1354 "ip address %s because of slip in "
1355 "ip_ratelimit_factor", addrbuf);
1356 return 1;
1357 }
1358 return 0;
1359 }
1360 return 1;
1361 }
1362
1363 int
worker_handle_request(struct comm_point * c,void * arg,int error,struct comm_reply * repinfo)1364 worker_handle_request(struct comm_point* c, void* arg, int error,
1365 struct comm_reply* repinfo)
1366 {
1367 struct worker* worker = (struct worker*)arg;
1368 int ret;
1369 hashvalue_type h;
1370 struct lruhash_entry* e;
1371 struct query_info qinfo;
1372 struct edns_data edns;
1373 struct edns_option* original_edns_list = NULL;
1374 enum acl_access acl;
1375 struct acl_addr* acladdr;
1376 int pre_edns_ip_ratelimit = 1;
1377 int rc = 0;
1378 int need_drop = 0;
1379 int is_expired_answer = 0;
1380 int is_secure_answer = 0;
1381 int rpz_passthru = 0;
1382 long long wait_queue_time = 0;
1383 /* We might have to chase a CNAME chain internally, in which case
1384 * we'll have up to two replies and combine them to build a complete
1385 * answer. These variables control this case. */
1386 struct ub_packed_rrset_key* alias_rrset = NULL;
1387 struct reply_info* partial_rep = NULL;
1388 struct query_info* lookup_qinfo = &qinfo;
1389 struct query_info qinfo_tmp; /* placeholder for lookup_qinfo */
1390 struct respip_client_info* cinfo = NULL, cinfo_tmp;
1391 struct timeval wait_time;
1392 struct check_request_result check_result = {0,0};
1393 memset(&qinfo, 0, sizeof(qinfo));
1394
1395 if((error != NETEVENT_NOERROR && error != NETEVENT_DONE)|| !repinfo) {
1396 /* some bad tcp query DNS formats give these error calls */
1397 verbose(VERB_ALGO, "handle request called with err=%d", error);
1398 return 0;
1399 }
1400
1401 if (worker->env.cfg->sock_queue_timeout && timeval_isset(&c->recv_tv)) {
1402 timeval_subtract(&wait_time, worker->env.now_tv, &c->recv_tv);
1403 wait_queue_time = wait_time.tv_sec * 1000000 + wait_time.tv_usec;
1404 if (worker->stats.max_query_time_us < wait_queue_time)
1405 worker->stats.max_query_time_us = wait_queue_time;
1406 if(wait_queue_time >
1407 (long long)(worker->env.cfg->sock_queue_timeout * 1000000)) {
1408 /* count and drop queries that were sitting in the socket queue too long */
1409 worker->stats.num_queries_timed_out++;
1410 return 0;
1411 }
1412 }
1413
1414 #ifdef USE_DNSCRYPT
1415 repinfo->max_udp_size = worker->daemon->cfg->max_udp_size;
1416 if(!dnsc_handle_curved_request(worker->daemon->dnscenv, repinfo)) {
1417 worker->stats.num_query_dnscrypt_crypted_malformed++;
1418 return 0;
1419 }
1420 if(c->dnscrypt && !repinfo->is_dnscrypted) {
1421 char buf[LDNS_MAX_DOMAINLEN+1];
1422 /* Check if this is unencrypted and asking for certs */
1423 worker_check_request(c->buffer, worker, &check_result);
1424 if(check_result.value != 0) {
1425 verbose(VERB_ALGO,
1426 "dnscrypt: worker check request: bad query.");
1427 log_addr(VERB_CLIENT,"from",&repinfo->client_addr,
1428 repinfo->client_addrlen);
1429 comm_point_drop_reply(repinfo);
1430 return 0;
1431 }
1432 if(!query_info_parse(&qinfo, c->buffer)) {
1433 verbose(VERB_ALGO,
1434 "dnscrypt: worker parse request: formerror.");
1435 log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1436 repinfo->client_addrlen);
1437 comm_point_drop_reply(repinfo);
1438 return 0;
1439 }
1440 dname_str(qinfo.qname, buf);
1441 if(!(qinfo.qtype == LDNS_RR_TYPE_TXT &&
1442 strcasecmp(buf,
1443 worker->daemon->dnscenv->provider_name) == 0)) {
1444 verbose(VERB_ALGO,
1445 "dnscrypt: not TXT \"%s\". Received: %s \"%s\"",
1446 worker->daemon->dnscenv->provider_name,
1447 sldns_rr_descript(qinfo.qtype)->_name,
1448 buf);
1449 comm_point_drop_reply(repinfo);
1450 worker->stats.num_query_dnscrypt_cleartext++;
1451 return 0;
1452 }
1453 worker->stats.num_query_dnscrypt_cert++;
1454 sldns_buffer_rewind(c->buffer);
1455 } else if(c->dnscrypt && repinfo->is_dnscrypted) {
1456 worker->stats.num_query_dnscrypt_crypted++;
1457 }
1458 #endif
1459 #ifdef USE_DNSTAP
1460 /*
1461 * sending src (client)/dst (local service) addresses over DNSTAP from incoming request handler
1462 */
1463 if(worker->dtenv.log_client_query_messages) {
1464 log_addr(VERB_ALGO, "request from client", &repinfo->client_addr, repinfo->client_addrlen);
1465 log_addr(VERB_ALGO, "to local addr", (void*)repinfo->c->socket->addr->ai_addr, repinfo->c->socket->addr->ai_addrlen);
1466 dt_msg_send_client_query(&worker->dtenv, &repinfo->client_addr, (void*)repinfo->c->socket->addr->ai_addr, c->type, c->buffer,
1467 ((worker->env.cfg->sock_queue_timeout && timeval_isset(&c->recv_tv))?&c->recv_tv:NULL));
1468 }
1469 #endif
1470 /* Check deny/refuse ACLs */
1471 if(repinfo->is_proxied) {
1472 if((ret=deny_refuse_all(c, &acl, worker, repinfo, &acladdr,
1473 worker->env.cfg->ede, 1, &check_result)) != -1) {
1474 if(ret == 1)
1475 goto send_reply;
1476 return ret;
1477 }
1478 }
1479 if((ret=deny_refuse_all(c, &acl, worker, repinfo, &acladdr,
1480 worker->env.cfg->ede, 0, &check_result)) != -1) {
1481 if(ret == 1)
1482 goto send_reply;
1483 return ret;
1484 }
1485
1486 worker_check_request(c->buffer, worker, &check_result);
1487 if(check_result.value != 0) {
1488 verbose(VERB_ALGO, "worker check request: bad query.");
1489 log_addr(VERB_CLIENT,"from",&repinfo->client_addr, repinfo->client_addrlen);
1490 if(check_result.value != -1) {
1491 LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1492 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1493 check_result.value);
1494 return 1;
1495 }
1496 comm_point_drop_reply(repinfo);
1497 return 0;
1498 }
1499
1500 worker->stats.num_queries++;
1501 pre_edns_ip_ratelimit = pre_edns_ip_ratelimit_check(acl);
1502
1503 /* If the IP rate limiting check needs extra EDNS information (e.g.,
1504 * DNS Cookies) postpone the check until after EDNS is parsed. */
1505 if(pre_edns_ip_ratelimit) {
1506 /* NOTE: we always check the repinfo->client_address.
1507 * IP ratelimiting is implicitly disabled for proxies. */
1508 if(!check_ip_ratelimit(worker, &repinfo->client_addr,
1509 repinfo->client_addrlen, 0, c->buffer)) {
1510 worker->stats.num_queries_ip_ratelimited++;
1511 comm_point_drop_reply(repinfo);
1512 return 0;
1513 }
1514 }
1515
1516 if(!query_info_parse(&qinfo, c->buffer)) {
1517 verbose(VERB_ALGO, "worker parse request: formerror.");
1518 log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1519 repinfo->client_addrlen);
1520 memset(&qinfo, 0, sizeof(qinfo)); /* zero qinfo.qname */
1521 if(worker_err_ratelimit(worker, LDNS_RCODE_FORMERR) == -1) {
1522 comm_point_drop_reply(repinfo);
1523 return 0;
1524 }
1525 sldns_buffer_rewind(c->buffer);
1526 LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1527 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1528 LDNS_RCODE_FORMERR);
1529 goto send_reply;
1530 }
1531 if(worker->env.cfg->log_queries) {
1532 char ip[128];
1533 addr_to_str(&repinfo->client_addr, repinfo->client_addrlen, ip, sizeof(ip));
1534 log_query_in(ip, qinfo.qname, qinfo.qtype, qinfo.qclass);
1535 }
1536 if(qinfo.qtype == LDNS_RR_TYPE_AXFR ||
1537 qinfo.qtype == LDNS_RR_TYPE_IXFR) {
1538 verbose(VERB_ALGO, "worker request: refused zone transfer.");
1539 log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1540 repinfo->client_addrlen);
1541 sldns_buffer_rewind(c->buffer);
1542 LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1543 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1544 LDNS_RCODE_REFUSED);
1545 if(worker->stats.extended) {
1546 worker->stats.qtype[qinfo.qtype]++;
1547 }
1548 goto send_reply;
1549 }
1550 if(qinfo.qtype == LDNS_RR_TYPE_OPT ||
1551 qinfo.qtype == LDNS_RR_TYPE_TSIG ||
1552 qinfo.qtype == LDNS_RR_TYPE_TKEY ||
1553 qinfo.qtype == LDNS_RR_TYPE_MAILA ||
1554 qinfo.qtype == LDNS_RR_TYPE_MAILB ||
1555 (qinfo.qtype >= 128 && qinfo.qtype <= 248)) {
1556 verbose(VERB_ALGO, "worker request: formerror for meta-type.");
1557 log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1558 repinfo->client_addrlen);
1559 if(worker_err_ratelimit(worker, LDNS_RCODE_FORMERR) == -1) {
1560 comm_point_drop_reply(repinfo);
1561 return 0;
1562 }
1563 sldns_buffer_rewind(c->buffer);
1564 LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1565 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1566 LDNS_RCODE_FORMERR);
1567 if(worker->stats.extended) {
1568 worker->stats.qtype[qinfo.qtype]++;
1569 }
1570 goto send_reply;
1571 }
1572 if((ret=parse_edns_from_query_pkt(
1573 c->buffer, &edns, worker->env.cfg, c, repinfo,
1574 (worker->env.now ? *worker->env.now : time(NULL)),
1575 worker->scratchpad)) != 0) {
1576 struct edns_data reply_edns;
1577 verbose(VERB_ALGO, "worker parse edns: formerror.");
1578 log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1579 repinfo->client_addrlen);
1580 memset(&reply_edns, 0, sizeof(reply_edns));
1581 reply_edns.edns_present = 1;
1582 error_encode(c->buffer, ret, &qinfo,
1583 *(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
1584 sldns_buffer_read_u16_at(c->buffer, 2), &reply_edns);
1585 regional_free_all(worker->scratchpad);
1586 goto send_reply;
1587 }
1588 if(edns.edns_present) {
1589 if(edns.edns_version != 0) {
1590 edns.opt_list_in = NULL;
1591 edns.opt_list_out = NULL;
1592 edns.opt_list_inplace_cb_out = NULL;
1593 verbose(VERB_ALGO, "query with bad edns version.");
1594 log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1595 repinfo->client_addrlen);
1596 extended_error_encode(c->buffer, EDNS_RCODE_BADVERS, &qinfo,
1597 *(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
1598 sldns_buffer_read_u16_at(c->buffer, 2), 0, &edns);
1599 regional_free_all(worker->scratchpad);
1600 goto send_reply;
1601 }
1602 if(edns.udp_size < NORMAL_UDP_SIZE &&
1603 worker->daemon->cfg->harden_short_bufsize) {
1604 verbose(VERB_QUERY, "worker request: EDNS bufsize %d ignored",
1605 (int)edns.udp_size);
1606 log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1607 repinfo->client_addrlen);
1608 edns.udp_size = NORMAL_UDP_SIZE;
1609 }
1610 }
1611
1612 /* Get stats for cookies */
1613 server_stats_downstream_cookie(&worker->stats, &edns);
1614
1615 /* If the IP rate limiting check was postponed, check now. */
1616 if(!pre_edns_ip_ratelimit) {
1617 /* NOTE: we always check the repinfo->client_address.
1618 * IP ratelimiting is implicitly disabled for proxies. */
1619 if(!check_ip_ratelimit(worker, &repinfo->client_addr,
1620 repinfo->client_addrlen, edns.cookie_valid,
1621 c->buffer)) {
1622 worker->stats.num_queries_ip_ratelimited++;
1623 comm_point_drop_reply(repinfo);
1624 return 0;
1625 }
1626 }
1627
1628 /* "if, else if" sequence below deals with downstream DNS Cookies */
1629 if(acl != acl_allow_cookie)
1630 ; /* pass; No cookie downstream processing whatsoever */
1631
1632 else if(edns.cookie_valid)
1633 ; /* pass; Valid cookie is good! */
1634
1635 else if(c->type != comm_udp)
1636 ; /* pass; Stateful transport */
1637
1638 else if(edns.cookie_present) {
1639 /* Cookie present, but not valid: Cookie was bad! */
1640 extended_error_encode(c->buffer,
1641 LDNS_EXT_RCODE_BADCOOKIE, &qinfo,
1642 *(uint16_t*)(void *)
1643 sldns_buffer_begin(c->buffer),
1644 sldns_buffer_read_u16_at(c->buffer, 2),
1645 0, &edns);
1646 regional_free_all(worker->scratchpad);
1647 goto send_reply;
1648 } else {
1649 /* Cookie required, but no cookie present on UDP */
1650 verbose(VERB_ALGO, "worker request: "
1651 "need cookie or stateful transport");
1652 log_addr(VERB_ALGO, "from",&repinfo->remote_addr
1653 , repinfo->remote_addrlen);
1654 EDNS_OPT_LIST_APPEND_EDE(&edns.opt_list_out,
1655 worker->scratchpad, LDNS_EDE_OTHER,
1656 "DNS Cookie needed for UDP replies");
1657 error_encode(c->buffer,
1658 (LDNS_RCODE_REFUSED|BIT_TC), &qinfo,
1659 *(uint16_t*)(void *)
1660 sldns_buffer_begin(c->buffer),
1661 sldns_buffer_read_u16_at(c->buffer, 2),
1662 &edns);
1663 regional_free_all(worker->scratchpad);
1664 goto send_reply;
1665 }
1666
1667 if(edns.udp_size > worker->daemon->cfg->max_udp_size &&
1668 c->type == comm_udp) {
1669 verbose(VERB_QUERY,
1670 "worker request: max UDP reply size modified"
1671 " (%d to max-udp-size)", (int)edns.udp_size);
1672 log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1673 repinfo->client_addrlen);
1674 edns.udp_size = worker->daemon->cfg->max_udp_size;
1675 }
1676 if(edns.udp_size < LDNS_HEADER_SIZE) {
1677 verbose(VERB_ALGO, "worker request: edns is too small.");
1678 log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1679 repinfo->client_addrlen);
1680 LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1681 LDNS_TC_SET(sldns_buffer_begin(c->buffer));
1682 LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1683 LDNS_RCODE_SERVFAIL);
1684 sldns_buffer_set_position(c->buffer, LDNS_HEADER_SIZE);
1685 sldns_buffer_write_at(c->buffer, 4,
1686 (uint8_t*)"\0\0\0\0\0\0\0\0", 8);
1687 sldns_buffer_flip(c->buffer);
1688 regional_free_all(worker->scratchpad);
1689 goto send_reply;
1690 }
1691 if(worker->stats.extended)
1692 server_stats_insquery(&worker->stats, c, qinfo.qtype,
1693 qinfo.qclass, &edns, repinfo);
1694 if(c->type != comm_udp)
1695 edns.udp_size = 65535; /* max size for TCP replies */
1696 if(qinfo.qclass == LDNS_RR_CLASS_CH && answer_chaos(worker, &qinfo,
1697 &edns, repinfo, c->buffer)) {
1698 regional_free_all(worker->scratchpad);
1699 goto send_reply;
1700 }
1701 if(LDNS_OPCODE_WIRE(sldns_buffer_begin(c->buffer)) ==
1702 LDNS_PACKET_NOTIFY) {
1703 answer_notify(worker, &qinfo, &edns, c->buffer,
1704 &repinfo->client_addr, repinfo->client_addrlen);
1705 regional_free_all(worker->scratchpad);
1706 goto send_reply;
1707 }
1708 if(local_zones_answer(worker->daemon->local_zones, &worker->env, &qinfo,
1709 &edns, c->buffer, worker->scratchpad, repinfo, acladdr->taglist,
1710 acladdr->taglen, acladdr->tag_actions,
1711 acladdr->tag_actions_size, acladdr->tag_datas,
1712 acladdr->tag_datas_size, worker->daemon->cfg->tagname,
1713 worker->daemon->cfg->num_tags, acladdr->view)) {
1714 regional_free_all(worker->scratchpad);
1715 if(sldns_buffer_limit(c->buffer) == 0) {
1716 comm_point_drop_reply(repinfo);
1717 return 0;
1718 }
1719 goto send_reply;
1720 }
1721 if(worker->env.auth_zones &&
1722 rpz_callback_from_worker_request(worker->env.auth_zones,
1723 &worker->env, &qinfo, &edns, c->buffer, worker->scratchpad,
1724 repinfo, acladdr->taglist, acladdr->taglen, &worker->stats,
1725 &rpz_passthru)) {
1726 regional_free_all(worker->scratchpad);
1727 if(sldns_buffer_limit(c->buffer) == 0) {
1728 comm_point_drop_reply(repinfo);
1729 return 0;
1730 }
1731 goto send_reply;
1732 }
1733 if(worker->env.auth_zones &&
1734 auth_zones_answer(worker->env.auth_zones, &worker->env,
1735 &qinfo, &edns, repinfo, c->buffer, worker->scratchpad)) {
1736 regional_free_all(worker->scratchpad);
1737 if(sldns_buffer_limit(c->buffer) == 0) {
1738 comm_point_drop_reply(repinfo);
1739 return 0;
1740 }
1741 /* set RA for everyone that can have recursion (based on
1742 * access control list) */
1743 if(LDNS_RD_WIRE(sldns_buffer_begin(c->buffer)) &&
1744 acl != acl_deny_non_local && acl != acl_refuse_non_local)
1745 LDNS_RA_SET(sldns_buffer_begin(c->buffer));
1746 goto send_reply;
1747 }
1748
1749 /* We've looked in our local zones. If the answer isn't there, we
1750 * might need to bail out based on ACLs now. */
1751 if((ret=deny_refuse_non_local(c, acl, worker, repinfo, acladdr,
1752 worker->env.cfg->ede, &check_result)) != -1)
1753 {
1754 regional_free_all(worker->scratchpad);
1755 if(ret == 1)
1756 goto send_reply;
1757 return ret;
1758 }
1759
1760 /* If this request does not have the recursion bit set, verify
1761 * ACLs allow the recursion bit to be treated as set. */
1762 if(!(LDNS_RD_WIRE(sldns_buffer_begin(c->buffer))) &&
1763 acl == acl_allow_setrd ) {
1764 LDNS_RD_SET(sldns_buffer_begin(c->buffer));
1765 }
1766
1767 /* If this request does not have the recursion bit set, verify
1768 * ACLs allow the snooping. */
1769 if(!(LDNS_RD_WIRE(sldns_buffer_begin(c->buffer))) &&
1770 acl != acl_allow_snoop ) {
1771 if(worker->env.cfg->ede) {
1772 EDNS_OPT_LIST_APPEND_EDE(&edns.opt_list_out,
1773 worker->scratchpad, LDNS_EDE_NOT_AUTHORITATIVE, "");
1774 }
1775 error_encode(c->buffer, LDNS_RCODE_REFUSED, &qinfo,
1776 *(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
1777 sldns_buffer_read_u16_at(c->buffer, 2), &edns);
1778 regional_free_all(worker->scratchpad);
1779 log_addr(VERB_ALGO, "refused nonrec (cache snoop) query from",
1780 &repinfo->client_addr, repinfo->client_addrlen);
1781
1782 goto send_reply;
1783 }
1784
1785 /* If we've found a local alias, replace the qname with the alias
1786 * target before resolving it. */
1787 if(qinfo.local_alias) {
1788 struct ub_packed_rrset_key* rrset = qinfo.local_alias->rrset;
1789 struct packed_rrset_data* d = rrset->entry.data;
1790
1791 /* Sanity check: our current implementation only supports
1792 * a single CNAME RRset as a local alias. */
1793 if(qinfo.local_alias->next ||
1794 rrset->rk.type != htons(LDNS_RR_TYPE_CNAME) ||
1795 d->count != 1) {
1796 log_err("assumption failure: unexpected local alias");
1797 regional_free_all(worker->scratchpad);
1798 return 0; /* drop it */
1799 }
1800 qinfo.qname = d->rr_data[0] + 2;
1801 qinfo.qname_len = d->rr_len[0] - 2;
1802 }
1803
1804 /* If we may apply IP-based actions to the answer, build the client
1805 * information. As this can be expensive, skip it if there is
1806 * absolutely no possibility of it. */
1807 if((worker->daemon->use_response_ip || worker->daemon->use_rpz) &&
1808 (qinfo.qtype == LDNS_RR_TYPE_A ||
1809 qinfo.qtype == LDNS_RR_TYPE_AAAA ||
1810 qinfo.qtype == LDNS_RR_TYPE_ANY)) {
1811 cinfo_tmp.taglist = acladdr->taglist;
1812 cinfo_tmp.taglen = acladdr->taglen;
1813 cinfo_tmp.tag_actions = acladdr->tag_actions;
1814 cinfo_tmp.tag_actions_size = acladdr->tag_actions_size;
1815 cinfo_tmp.tag_datas = acladdr->tag_datas;
1816 cinfo_tmp.tag_datas_size = acladdr->tag_datas_size;
1817 cinfo_tmp.view = acladdr->view;
1818 cinfo_tmp.respip_set = worker->daemon->respip_set;
1819 cinfo = &cinfo_tmp;
1820 }
1821
1822 /* Keep the original edns list around. The pointer could change if there is
1823 * a cached answer (through the inplace callback function there).
1824 * No need to actually copy the contents as they shouldn't change.
1825 * Used while prefetching and subnet is enabled. */
1826 original_edns_list = edns.opt_list_in;
1827 lookup_cache:
1828 /* Lookup the cache. In case we chase an intermediate CNAME chain
1829 * this is a two-pass operation, and lookup_qinfo is different for
1830 * each pass. We should still pass the original qinfo to
1831 * answer_from_cache(), however, since it's used to build the reply. */
1832 if(!edns_bypass_cache_stage(edns.opt_list_in, &worker->env)) {
1833 is_expired_answer = 0;
1834 is_secure_answer = 0;
1835 h = query_info_hash(lookup_qinfo, sldns_buffer_read_u16_at(c->buffer, 2));
1836 if((e=slabhash_lookup(worker->env.msg_cache, h, lookup_qinfo, 0))) {
1837 struct reply_info* rep = (struct reply_info*)e->data;
1838 /* answer from cache - we have acquired a readlock on it */
1839 if(answer_from_cache(worker, &qinfo, cinfo, &need_drop,
1840 &is_expired_answer, &is_secure_answer,
1841 &alias_rrset, &partial_rep, rep,
1842 *(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
1843 sldns_buffer_read_u16_at(c->buffer, 2), repinfo,
1844 &edns)) {
1845 /* prefetch it if the prefetch TTL expired.
1846 * Note that if there is more than one pass
1847 * its qname must be that used for cache
1848 * lookup. */
1849 if((worker->env.cfg->prefetch &&
1850 *worker->env.now >= rep->prefetch_ttl) ||
1851 (worker->env.cfg->serve_expired &&
1852 *worker->env.now > rep->ttl)) {
1853
1854 time_t leeway = rep->ttl - *worker->env.now;
1855 if(rep->ttl < *worker->env.now)
1856 leeway = 0;
1857 lock_rw_unlock(&e->lock);
1858
1859 reply_and_prefetch(worker, lookup_qinfo,
1860 sldns_buffer_read_u16_at(c->buffer, 2),
1861 repinfo, leeway,
1862 (partial_rep || need_drop),
1863 rpz_passthru,
1864 original_edns_list);
1865 if(!partial_rep) {
1866 rc = 0;
1867 regional_free_all(worker->scratchpad);
1868 goto send_reply_rc;
1869 }
1870 } else if(!partial_rep) {
1871 lock_rw_unlock(&e->lock);
1872 regional_free_all(worker->scratchpad);
1873 goto send_reply;
1874 } else {
1875 /* Note that we've already released the
1876 * lock if we're here after prefetch. */
1877 lock_rw_unlock(&e->lock);
1878 }
1879 /* We've found a partial reply ending with an
1880 * alias. Replace the lookup qinfo for the
1881 * alias target and lookup the cache again to
1882 * (possibly) complete the reply. As we're
1883 * passing the "base" reply, there will be no
1884 * more alias chasing. */
1885 memset(&qinfo_tmp, 0, sizeof(qinfo_tmp));
1886 get_cname_target(alias_rrset, &qinfo_tmp.qname,
1887 &qinfo_tmp.qname_len);
1888 if(!qinfo_tmp.qname) {
1889 log_err("unexpected: invalid answer alias");
1890 regional_free_all(worker->scratchpad);
1891 return 0; /* drop query */
1892 }
1893 qinfo_tmp.qtype = qinfo.qtype;
1894 qinfo_tmp.qclass = qinfo.qclass;
1895 lookup_qinfo = &qinfo_tmp;
1896 goto lookup_cache;
1897 }
1898 verbose(VERB_ALGO, "answer from the cache failed");
1899 lock_rw_unlock(&e->lock);
1900 }
1901
1902 if(!LDNS_RD_WIRE(sldns_buffer_begin(c->buffer))) {
1903 if(answer_norec_from_cache(worker, &qinfo,
1904 *(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
1905 sldns_buffer_read_u16_at(c->buffer, 2), repinfo,
1906 &edns)) {
1907 regional_free_all(worker->scratchpad);
1908 goto send_reply;
1909 }
1910 verbose(VERB_ALGO, "answer norec from cache -- "
1911 "need to validate or not primed");
1912 }
1913 }
1914 sldns_buffer_rewind(c->buffer);
1915 server_stats_querymiss(&worker->stats, worker);
1916
1917 if(verbosity >= VERB_CLIENT) {
1918 if(c->type == comm_udp)
1919 log_addr(VERB_CLIENT, "udp request from",
1920 &repinfo->client_addr, repinfo->client_addrlen);
1921 else log_addr(VERB_CLIENT, "tcp request from",
1922 &repinfo->client_addr, repinfo->client_addrlen);
1923 }
1924
1925 /* grab a work request structure for this new request */
1926 mesh_new_client(worker->env.mesh, &qinfo, cinfo,
1927 sldns_buffer_read_u16_at(c->buffer, 2),
1928 &edns, repinfo, *(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
1929 rpz_passthru);
1930 regional_free_all(worker->scratchpad);
1931 worker_mem_report(worker, NULL);
1932 return 0;
1933
1934 send_reply:
1935 rc = 1;
1936 send_reply_rc:
1937 if(need_drop) {
1938 comm_point_drop_reply(repinfo);
1939 return 0;
1940 }
1941 if(is_expired_answer) {
1942 worker->stats.ans_expired++;
1943 }
1944 server_stats_insrcode(&worker->stats, c->buffer);
1945 if(worker->stats.extended) {
1946 if(is_secure_answer) worker->stats.ans_secure++;
1947 }
1948 #ifdef USE_DNSTAP
1949 /*
1950 * sending src (client)/dst (local service) addresses over DNSTAP from send_reply code label (when we serviced local zone for ex.)
1951 */
1952 if(worker->dtenv.log_client_response_messages) {
1953 log_addr(VERB_ALGO, "from local addr", (void*)repinfo->c->socket->addr->ai_addr, repinfo->c->socket->addr->ai_addrlen);
1954 log_addr(VERB_ALGO, "response to client", &repinfo->client_addr, repinfo->client_addrlen);
1955 dt_msg_send_client_response(&worker->dtenv, &repinfo->client_addr, (void*)repinfo->c->socket->addr->ai_addr, c->type, c->buffer);
1956 }
1957 #endif
1958 if(worker->env.cfg->log_replies)
1959 {
1960 struct timeval tv;
1961 memset(&tv, 0, sizeof(tv));
1962 if(qinfo.local_alias && qinfo.local_alias->rrset &&
1963 qinfo.local_alias->rrset->rk.dname) {
1964 /* log original qname, before the local alias was
1965 * used to resolve that CNAME to something else */
1966 qinfo.qname = qinfo.local_alias->rrset->rk.dname;
1967 log_reply_info(NO_VERBOSE, &qinfo,
1968 &repinfo->client_addr, repinfo->client_addrlen,
1969 tv, 1, c->buffer);
1970 } else {
1971 log_reply_info(NO_VERBOSE, &qinfo,
1972 &repinfo->client_addr, repinfo->client_addrlen,
1973 tv, 1, c->buffer);
1974 }
1975 }
1976 #ifdef USE_DNSCRYPT
1977 if(!dnsc_handle_uncurved_request(repinfo)) {
1978 return 0;
1979 }
1980 #endif
1981 return rc;
1982 }
1983
1984 void
worker_sighandler(int sig,void * arg)1985 worker_sighandler(int sig, void* arg)
1986 {
1987 /* note that log, print, syscalls here give race conditions.
1988 * And cause hangups if the log-lock is held by the application. */
1989 struct worker* worker = (struct worker*)arg;
1990 switch(sig) {
1991 #ifdef SIGHUP
1992 case SIGHUP:
1993 comm_base_exit(worker->base);
1994 break;
1995 #endif
1996 #ifdef SIGBREAK
1997 case SIGBREAK:
1998 #endif
1999 case SIGINT:
2000 worker->need_to_exit = 1;
2001 comm_base_exit(worker->base);
2002 break;
2003 #ifdef SIGQUIT
2004 case SIGQUIT:
2005 worker->need_to_exit = 1;
2006 comm_base_exit(worker->base);
2007 break;
2008 #endif
2009 case SIGTERM:
2010 worker->need_to_exit = 1;
2011 comm_base_exit(worker->base);
2012 break;
2013 default:
2014 /* unknown signal, ignored */
2015 break;
2016 }
2017 }
2018
2019 /** restart statistics timer for worker, if enabled */
2020 static void
worker_restart_timer(struct worker * worker)2021 worker_restart_timer(struct worker* worker)
2022 {
2023 if(worker->env.cfg->stat_interval > 0) {
2024 struct timeval tv;
2025 #ifndef S_SPLINT_S
2026 tv.tv_sec = worker->env.cfg->stat_interval;
2027 tv.tv_usec = 0;
2028 #endif
2029 comm_timer_set(worker->stat_timer, &tv);
2030 }
2031 }
2032
worker_stat_timer_cb(void * arg)2033 void worker_stat_timer_cb(void* arg)
2034 {
2035 struct worker* worker = (struct worker*)arg;
2036 server_stats_log(&worker->stats, worker, worker->thread_num);
2037 mesh_stats(worker->env.mesh, "mesh has");
2038 worker_mem_report(worker, NULL);
2039 /* SHM is enabled, process data to SHM */
2040 if (worker->daemon->cfg->shm_enable) {
2041 shm_main_run(worker);
2042 }
2043 if(!worker->daemon->cfg->stat_cumulative) {
2044 worker_stats_clear(worker);
2045 }
2046 /* start next timer */
2047 worker_restart_timer(worker);
2048 }
2049
worker_probe_timer_cb(void * arg)2050 void worker_probe_timer_cb(void* arg)
2051 {
2052 struct worker* worker = (struct worker*)arg;
2053 struct timeval tv;
2054 #ifndef S_SPLINT_S
2055 tv.tv_sec = (time_t)autr_probe_timer(&worker->env);
2056 tv.tv_usec = 0;
2057 #endif
2058 if(tv.tv_sec != 0)
2059 comm_timer_set(worker->env.probe_timer, &tv);
2060 }
2061
2062 struct worker*
worker_create(struct daemon * daemon,int id,int * ports,int n)2063 worker_create(struct daemon* daemon, int id, int* ports, int n)
2064 {
2065 unsigned int seed;
2066 struct worker* worker = (struct worker*)calloc(1,
2067 sizeof(struct worker));
2068 if(!worker)
2069 return NULL;
2070 worker->numports = n;
2071 worker->ports = (int*)memdup(ports, sizeof(int)*n);
2072 if(!worker->ports) {
2073 free(worker);
2074 return NULL;
2075 }
2076 worker->daemon = daemon;
2077 worker->thread_num = id;
2078 if(!(worker->cmd = tube_create())) {
2079 free(worker->ports);
2080 free(worker);
2081 return NULL;
2082 }
2083 /* create random state here to avoid locking trouble in RAND_bytes */
2084 if(!(worker->rndstate = ub_initstate(daemon->rand))) {
2085 log_err("could not init random numbers.");
2086 tube_delete(worker->cmd);
2087 free(worker->ports);
2088 free(worker);
2089 return NULL;
2090 }
2091 explicit_bzero(&seed, sizeof(seed));
2092 return worker;
2093 }
2094
2095 int
worker_init(struct worker * worker,struct config_file * cfg,struct listen_port * ports,int do_sigs)2096 worker_init(struct worker* worker, struct config_file *cfg,
2097 struct listen_port* ports, int do_sigs)
2098 {
2099 #ifdef USE_DNSTAP
2100 struct dt_env* dtenv = &worker->dtenv;
2101 #else
2102 void* dtenv = NULL;
2103 #endif
2104 #ifdef HAVE_GETTID
2105 worker->thread_tid = gettid();
2106 #endif
2107 worker->need_to_exit = 0;
2108 worker->base = comm_base_create(do_sigs);
2109 if(!worker->base) {
2110 log_err("could not create event handling base");
2111 worker_delete(worker);
2112 return 0;
2113 }
2114 comm_base_set_slow_accept_handlers(worker->base, &worker_stop_accept,
2115 &worker_start_accept, worker);
2116 if(do_sigs) {
2117 #ifdef SIGHUP
2118 ub_thread_sig_unblock(SIGHUP);
2119 #endif
2120 #ifdef SIGBREAK
2121 ub_thread_sig_unblock(SIGBREAK);
2122 #endif
2123 ub_thread_sig_unblock(SIGINT);
2124 #ifdef SIGQUIT
2125 ub_thread_sig_unblock(SIGQUIT);
2126 #endif
2127 ub_thread_sig_unblock(SIGTERM);
2128 #ifndef LIBEVENT_SIGNAL_PROBLEM
2129 worker->comsig = comm_signal_create(worker->base,
2130 worker_sighandler, worker);
2131 if(!worker->comsig
2132 #ifdef SIGHUP
2133 || !comm_signal_bind(worker->comsig, SIGHUP)
2134 #endif
2135 #ifdef SIGQUIT
2136 || !comm_signal_bind(worker->comsig, SIGQUIT)
2137 #endif
2138 || !comm_signal_bind(worker->comsig, SIGTERM)
2139 #ifdef SIGBREAK
2140 || !comm_signal_bind(worker->comsig, SIGBREAK)
2141 #endif
2142 || !comm_signal_bind(worker->comsig, SIGINT)) {
2143 log_err("could not create signal handlers");
2144 worker_delete(worker);
2145 return 0;
2146 }
2147 #endif /* LIBEVENT_SIGNAL_PROBLEM */
2148 if(!daemon_remote_open_accept(worker->daemon->rc,
2149 worker->daemon->rc_ports, worker)) {
2150 worker_delete(worker);
2151 return 0;
2152 }
2153 #ifdef UB_ON_WINDOWS
2154 wsvc_setup_worker(worker);
2155 #endif /* UB_ON_WINDOWS */
2156 } else { /* !do_sigs */
2157 worker->comsig = NULL;
2158 }
2159 #ifdef USE_DNSTAP
2160 if(cfg->dnstap) {
2161 log_assert(worker->daemon->dtenv != NULL);
2162 memcpy(&worker->dtenv, worker->daemon->dtenv, sizeof(struct dt_env));
2163 if(!dt_init(&worker->dtenv, worker->base))
2164 fatal_exit("dt_init failed");
2165 }
2166 #endif
2167 worker->front = listen_create(worker->base, ports,
2168 cfg->msg_buffer_size, (int)cfg->incoming_num_tcp,
2169 cfg->do_tcp_keepalive
2170 ? cfg->tcp_keepalive_timeout
2171 : cfg->tcp_idle_timeout,
2172 cfg->harden_large_queries, cfg->http_max_streams,
2173 cfg->http_endpoint, cfg->http_notls_downstream,
2174 worker->daemon->tcl, worker->daemon->listen_sslctx,
2175 dtenv, worker_handle_request, worker);
2176 if(!worker->front) {
2177 log_err("could not create listening sockets");
2178 worker_delete(worker);
2179 return 0;
2180 }
2181 worker->back = outside_network_create(worker->base,
2182 cfg->msg_buffer_size, (size_t)cfg->outgoing_num_ports,
2183 cfg->out_ifs, cfg->num_out_ifs, cfg->do_ip4, cfg->do_ip6,
2184 cfg->do_tcp?cfg->outgoing_num_tcp:0, cfg->ip_dscp,
2185 worker->daemon->env->infra_cache, worker->rndstate,
2186 cfg->use_caps_bits_for_id, worker->ports, worker->numports,
2187 cfg->unwanted_threshold, cfg->outgoing_tcp_mss,
2188 &worker_alloc_cleanup, worker,
2189 cfg->do_udp || cfg->udp_upstream_without_downstream,
2190 worker->daemon->connect_sslctx, cfg->delay_close,
2191 cfg->tls_use_sni, dtenv, cfg->udp_connect,
2192 cfg->max_reuse_tcp_queries, cfg->tcp_reuse_timeout,
2193 cfg->tcp_auth_query_timeout);
2194 if(!worker->back) {
2195 log_err("could not create outgoing sockets");
2196 worker_delete(worker);
2197 return 0;
2198 }
2199 iterator_set_ip46_support(&worker->daemon->mods, worker->daemon->env,
2200 worker->back);
2201 /* start listening to commands */
2202 if(!tube_setup_bg_listen(worker->cmd, worker->base,
2203 &worker_handle_control_cmd, worker)) {
2204 log_err("could not create control compt.");
2205 worker_delete(worker);
2206 return 0;
2207 }
2208 worker->stat_timer = comm_timer_create(worker->base,
2209 worker_stat_timer_cb, worker);
2210 if(!worker->stat_timer) {
2211 log_err("could not create statistics timer");
2212 }
2213
2214 /* we use the msg_buffer_size as a good estimate for what the
2215 * user wants for memory usage sizes */
2216 worker->scratchpad = regional_create_custom(cfg->msg_buffer_size);
2217 if(!worker->scratchpad) {
2218 log_err("malloc failure");
2219 worker_delete(worker);
2220 return 0;
2221 }
2222
2223 server_stats_init(&worker->stats, cfg);
2224 worker->alloc = worker->daemon->worker_allocs[worker->thread_num];
2225 alloc_set_id_cleanup(worker->alloc, &worker_alloc_cleanup, worker);
2226 worker->env = *worker->daemon->env;
2227 comm_base_timept(worker->base, &worker->env.now, &worker->env.now_tv);
2228 worker->env.worker = worker;
2229 worker->env.worker_base = worker->base;
2230 worker->env.send_query = &worker_send_query;
2231 worker->env.alloc = worker->alloc;
2232 worker->env.outnet = worker->back;
2233 worker->env.rnd = worker->rndstate;
2234 /* If case prefetch is triggered, the corresponding mesh will clear
2235 * the scratchpad for the module env in the middle of request handling.
2236 * It would be prone to a use-after-free kind of bug, so we avoid
2237 * sharing it with worker's own scratchpad at the cost of having
2238 * one more pad per worker. */
2239 worker->env.scratch = regional_create_custom(cfg->msg_buffer_size);
2240 if(!worker->env.scratch) {
2241 log_err("malloc failure");
2242 worker_delete(worker);
2243 return 0;
2244 }
2245 worker->env.mesh = mesh_create(&worker->daemon->mods, &worker->env);
2246 if(!worker->env.mesh) {
2247 log_err("malloc failure");
2248 worker_delete(worker);
2249 return 0;
2250 }
2251 /* Pass on daemon variables that we would need in the mesh area */
2252 worker->env.mesh->use_response_ip = worker->daemon->use_response_ip;
2253 worker->env.mesh->use_rpz = worker->daemon->use_rpz;
2254
2255 worker->env.detach_subs = &mesh_detach_subs;
2256 worker->env.attach_sub = &mesh_attach_sub;
2257 worker->env.add_sub = &mesh_add_sub;
2258 worker->env.kill_sub = &mesh_state_delete;
2259 worker->env.detect_cycle = &mesh_detect_cycle;
2260 worker->env.scratch_buffer = sldns_buffer_new(cfg->msg_buffer_size);
2261 if(!worker->env.scratch_buffer) {
2262 log_err("malloc failure");
2263 worker_delete(worker);
2264 return 0;
2265 }
2266 if(!(worker->env.fwds = forwards_create()) ||
2267 !forwards_apply_cfg(worker->env.fwds, cfg)) {
2268 log_err("Could not set forward zones");
2269 worker_delete(worker);
2270 return 0;
2271 }
2272 if(!(worker->env.hints = hints_create()) ||
2273 !hints_apply_cfg(worker->env.hints, cfg)) {
2274 log_err("Could not set root or stub hints");
2275 worker_delete(worker);
2276 return 0;
2277 }
2278 /* one probe timer per process -- if we have 5011 anchors */
2279 if(autr_get_num_anchors(worker->env.anchors) > 0
2280 #ifndef THREADS_DISABLED
2281 && worker->thread_num == 0
2282 #endif
2283 ) {
2284 struct timeval tv;
2285 tv.tv_sec = 0;
2286 tv.tv_usec = 0;
2287 worker->env.probe_timer = comm_timer_create(worker->base,
2288 worker_probe_timer_cb, worker);
2289 if(!worker->env.probe_timer) {
2290 log_err("could not create 5011-probe timer");
2291 } else {
2292 /* let timer fire, then it can reset itself */
2293 comm_timer_set(worker->env.probe_timer, &tv);
2294 }
2295 }
2296 /* zone transfer tasks, setup once per process, if any */
2297 if(worker->env.auth_zones
2298 #ifndef THREADS_DISABLED
2299 && worker->thread_num == 0
2300 #endif
2301 ) {
2302 auth_xfer_pickup_initial(worker->env.auth_zones, &worker->env);
2303 auth_zones_pickup_zonemd_verify(worker->env.auth_zones,
2304 &worker->env);
2305 }
2306 #ifdef USE_DNSTAP
2307 if(worker->daemon->cfg->dnstap
2308 #ifndef THREADS_DISABLED
2309 && worker->thread_num == 0
2310 #endif
2311 ) {
2312 if(!dt_io_thread_start(dtenv->dtio, comm_base_internal(
2313 worker->base), worker->daemon->num)) {
2314 log_err("could not start dnstap io thread");
2315 worker_delete(worker);
2316 return 0;
2317 }
2318 }
2319 #endif /* USE_DNSTAP */
2320 worker_mem_report(worker, NULL);
2321 /* if statistics enabled start timer */
2322 if(worker->env.cfg->stat_interval > 0) {
2323 verbose(VERB_ALGO, "set statistics interval %d secs",
2324 worker->env.cfg->stat_interval);
2325 worker_restart_timer(worker);
2326 }
2327 pp_init(&sldns_write_uint16, &sldns_write_uint32);
2328 return 1;
2329 }
2330
2331 void
worker_work(struct worker * worker)2332 worker_work(struct worker* worker)
2333 {
2334 comm_base_dispatch(worker->base);
2335 }
2336
2337 void
worker_delete(struct worker * worker)2338 worker_delete(struct worker* worker)
2339 {
2340 if(!worker)
2341 return;
2342 if(worker->env.mesh && verbosity >= VERB_OPS) {
2343 server_stats_log(&worker->stats, worker, worker->thread_num);
2344 mesh_stats(worker->env.mesh, "mesh has");
2345 worker_mem_report(worker, NULL);
2346 }
2347 outside_network_quit_prepare(worker->back);
2348 mesh_delete(worker->env.mesh);
2349 sldns_buffer_free(worker->env.scratch_buffer);
2350 forwards_delete(worker->env.fwds);
2351 hints_delete(worker->env.hints);
2352 listen_delete(worker->front);
2353 outside_network_delete(worker->back);
2354 comm_signal_delete(worker->comsig);
2355 tube_delete(worker->cmd);
2356 comm_timer_delete(worker->stat_timer);
2357 comm_timer_delete(worker->env.probe_timer);
2358 free(worker->ports);
2359 if(worker->thread_num == 0) {
2360 #ifdef UB_ON_WINDOWS
2361 wsvc_desetup_worker(worker);
2362 #endif /* UB_ON_WINDOWS */
2363 }
2364 #ifdef USE_DNSTAP
2365 if(worker->daemon->cfg->dnstap
2366 #ifndef THREADS_DISABLED
2367 && worker->thread_num == 0
2368 #endif
2369 ) {
2370 dt_io_thread_stop(worker->dtenv.dtio);
2371 }
2372 dt_deinit(&worker->dtenv);
2373 #endif /* USE_DNSTAP */
2374 comm_base_delete(worker->base);
2375 ub_randfree(worker->rndstate);
2376 /* don't touch worker->alloc, as it's maintained in daemon */
2377 regional_destroy(worker->env.scratch);
2378 regional_destroy(worker->scratchpad);
2379 free(worker);
2380 }
2381
2382 struct outbound_entry*
worker_send_query(struct query_info * qinfo,uint16_t flags,int dnssec,int want_dnssec,int nocaps,int check_ratelimit,struct sockaddr_storage * addr,socklen_t addrlen,uint8_t * zone,size_t zonelen,int tcp_upstream,int ssl_upstream,char * tls_auth_name,struct module_qstate * q,int * was_ratelimited)2383 worker_send_query(struct query_info* qinfo, uint16_t flags, int dnssec,
2384 int want_dnssec, int nocaps, int check_ratelimit,
2385 struct sockaddr_storage* addr, socklen_t addrlen, uint8_t* zone,
2386 size_t zonelen, int tcp_upstream, int ssl_upstream, char* tls_auth_name,
2387 struct module_qstate* q, int* was_ratelimited)
2388 {
2389 struct worker* worker = q->env->worker;
2390 struct outbound_entry* e = (struct outbound_entry*)regional_alloc(
2391 q->region, sizeof(*e));
2392 if(!e)
2393 return NULL;
2394 e->qstate = q;
2395 e->qsent = outnet_serviced_query(worker->back, qinfo, flags, dnssec,
2396 want_dnssec, nocaps, check_ratelimit, tcp_upstream,
2397 ssl_upstream, tls_auth_name, addr, addrlen, zone, zonelen, q,
2398 worker_handle_service_reply, e, worker->back->udp_buff, q->env,
2399 was_ratelimited);
2400 if(!e->qsent) {
2401 return NULL;
2402 }
2403 return e;
2404 }
2405
2406 void
worker_alloc_cleanup(void * arg)2407 worker_alloc_cleanup(void* arg)
2408 {
2409 struct worker* worker = (struct worker*)arg;
2410 slabhash_clear(&worker->env.rrset_cache->table);
2411 slabhash_clear(worker->env.msg_cache);
2412 }
2413
worker_stats_clear(struct worker * worker)2414 void worker_stats_clear(struct worker* worker)
2415 {
2416 server_stats_init(&worker->stats, worker->env.cfg);
2417 mesh_stats_clear(worker->env.mesh);
2418 worker->back->unwanted_replies = 0;
2419 worker->back->num_tcp_outgoing = 0;
2420 worker->back->num_udp_outgoing = 0;
2421 }
2422
worker_start_accept(void * arg)2423 void worker_start_accept(void* arg)
2424 {
2425 struct worker* worker = (struct worker*)arg;
2426 listen_start_accept(worker->front);
2427 if(worker->thread_num == 0)
2428 daemon_remote_start_accept(worker->daemon->rc);
2429 }
2430
worker_stop_accept(void * arg)2431 void worker_stop_accept(void* arg)
2432 {
2433 struct worker* worker = (struct worker*)arg;
2434 listen_stop_accept(worker->front);
2435 if(worker->thread_num == 0)
2436 daemon_remote_stop_accept(worker->daemon->rc);
2437 }
2438
2439 /* --- fake callbacks for fptr_wlist to work --- */
libworker_send_query(struct query_info * ATTR_UNUSED (qinfo),uint16_t ATTR_UNUSED (flags),int ATTR_UNUSED (dnssec),int ATTR_UNUSED (want_dnssec),int ATTR_UNUSED (nocaps),int ATTR_UNUSED (check_ratelimit),struct sockaddr_storage * ATTR_UNUSED (addr),socklen_t ATTR_UNUSED (addrlen),uint8_t * ATTR_UNUSED (zone),size_t ATTR_UNUSED (zonelen),int ATTR_UNUSED (tcp_upstream),int ATTR_UNUSED (ssl_upstream),char * ATTR_UNUSED (tls_auth_name),struct module_qstate * ATTR_UNUSED (q),int * ATTR_UNUSED (was_ratelimited))2440 struct outbound_entry* libworker_send_query(
2441 struct query_info* ATTR_UNUSED(qinfo),
2442 uint16_t ATTR_UNUSED(flags), int ATTR_UNUSED(dnssec),
2443 int ATTR_UNUSED(want_dnssec), int ATTR_UNUSED(nocaps),
2444 int ATTR_UNUSED(check_ratelimit),
2445 struct sockaddr_storage* ATTR_UNUSED(addr), socklen_t ATTR_UNUSED(addrlen),
2446 uint8_t* ATTR_UNUSED(zone), size_t ATTR_UNUSED(zonelen), int ATTR_UNUSED(tcp_upstream),
2447 int ATTR_UNUSED(ssl_upstream), char* ATTR_UNUSED(tls_auth_name),
2448 struct module_qstate* ATTR_UNUSED(q), int* ATTR_UNUSED(was_ratelimited))
2449 {
2450 log_assert(0);
2451 return 0;
2452 }
2453
libworker_handle_service_reply(struct comm_point * ATTR_UNUSED (c),void * ATTR_UNUSED (arg),int ATTR_UNUSED (error),struct comm_reply * ATTR_UNUSED (reply_info))2454 int libworker_handle_service_reply(struct comm_point* ATTR_UNUSED(c),
2455 void* ATTR_UNUSED(arg), int ATTR_UNUSED(error),
2456 struct comm_reply* ATTR_UNUSED(reply_info))
2457 {
2458 log_assert(0);
2459 return 0;
2460 }
2461
libworker_handle_control_cmd(struct tube * ATTR_UNUSED (tube),uint8_t * ATTR_UNUSED (buffer),size_t ATTR_UNUSED (len),int ATTR_UNUSED (error),void * ATTR_UNUSED (arg))2462 void libworker_handle_control_cmd(struct tube* ATTR_UNUSED(tube),
2463 uint8_t* ATTR_UNUSED(buffer), size_t ATTR_UNUSED(len),
2464 int ATTR_UNUSED(error), void* ATTR_UNUSED(arg))
2465 {
2466 log_assert(0);
2467 }
2468
libworker_fg_done_cb(void * ATTR_UNUSED (arg),int ATTR_UNUSED (rcode),sldns_buffer * ATTR_UNUSED (buf),enum sec_status ATTR_UNUSED (s),char * ATTR_UNUSED (why_bogus),int ATTR_UNUSED (was_ratelimited))2469 void libworker_fg_done_cb(void* ATTR_UNUSED(arg), int ATTR_UNUSED(rcode),
2470 sldns_buffer* ATTR_UNUSED(buf), enum sec_status ATTR_UNUSED(s),
2471 char* ATTR_UNUSED(why_bogus), int ATTR_UNUSED(was_ratelimited))
2472 {
2473 log_assert(0);
2474 }
2475
libworker_bg_done_cb(void * ATTR_UNUSED (arg),int ATTR_UNUSED (rcode),sldns_buffer * ATTR_UNUSED (buf),enum sec_status ATTR_UNUSED (s),char * ATTR_UNUSED (why_bogus),int ATTR_UNUSED (was_ratelimited))2476 void libworker_bg_done_cb(void* ATTR_UNUSED(arg), int ATTR_UNUSED(rcode),
2477 sldns_buffer* ATTR_UNUSED(buf), enum sec_status ATTR_UNUSED(s),
2478 char* ATTR_UNUSED(why_bogus), int ATTR_UNUSED(was_ratelimited))
2479 {
2480 log_assert(0);
2481 }
2482
libworker_event_done_cb(void * ATTR_UNUSED (arg),int ATTR_UNUSED (rcode),sldns_buffer * ATTR_UNUSED (buf),enum sec_status ATTR_UNUSED (s),char * ATTR_UNUSED (why_bogus),int ATTR_UNUSED (was_ratelimited))2483 void libworker_event_done_cb(void* ATTR_UNUSED(arg), int ATTR_UNUSED(rcode),
2484 sldns_buffer* ATTR_UNUSED(buf), enum sec_status ATTR_UNUSED(s),
2485 char* ATTR_UNUSED(why_bogus), int ATTR_UNUSED(was_ratelimited))
2486 {
2487 log_assert(0);
2488 }
2489
context_query_cmp(const void * ATTR_UNUSED (a),const void * ATTR_UNUSED (b))2490 int context_query_cmp(const void* ATTR_UNUSED(a), const void* ATTR_UNUSED(b))
2491 {
2492 log_assert(0);
2493 return 0;
2494 }
2495
order_lock_cmp(const void * ATTR_UNUSED (e1),const void * ATTR_UNUSED (e2))2496 int order_lock_cmp(const void* ATTR_UNUSED(e1), const void* ATTR_UNUSED(e2))
2497 {
2498 log_assert(0);
2499 return 0;
2500 }
2501
codeline_cmp(const void * ATTR_UNUSED (a),const void * ATTR_UNUSED (b))2502 int codeline_cmp(const void* ATTR_UNUSED(a), const void* ATTR_UNUSED(b))
2503 {
2504 log_assert(0);
2505 return 0;
2506 }
2507
2508 #ifdef USE_DNSTAP
dtio_tap_callback(int ATTR_UNUSED (fd),short ATTR_UNUSED (ev),void * ATTR_UNUSED (arg))2509 void dtio_tap_callback(int ATTR_UNUSED(fd), short ATTR_UNUSED(ev),
2510 void* ATTR_UNUSED(arg))
2511 {
2512 log_assert(0);
2513 }
2514 #endif
2515
2516 #ifdef USE_DNSTAP
dtio_mainfdcallback(int ATTR_UNUSED (fd),short ATTR_UNUSED (ev),void * ATTR_UNUSED (arg))2517 void dtio_mainfdcallback(int ATTR_UNUSED(fd), short ATTR_UNUSED(ev),
2518 void* ATTR_UNUSED(arg))
2519 {
2520 log_assert(0);
2521 }
2522 #endif
2523