xref: /freebsd/contrib/unbound/daemon/worker.c (revision 87b759f0fa1f7554d50ce640c40138512bbded44)
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
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 	if(worker->daemon->env->fwds)
165 		log_info("forwards=%u", (unsigned)forwards_get_mem(worker->env.fwds));
166 	if(worker->daemon->env->hints)
167 		log_info("hints=%u", (unsigned)hints_get_mem(worker->env.hints));
168 	if(worker->thread_num == 0)
169 		me += acl_list_get_mem(worker->daemon->acl);
170 	if(cur_serv) {
171 		me += serviced_get_mem(cur_serv);
172 	}
173 	total = front+back+mesh+msg+rrset+infra+iter+val+ac+superac+me;
174 #ifdef CLIENT_SUBNET
175 	total += subnet;
176 	log_info("Memory conditions: %u front=%u back=%u mesh=%u msg=%u "
177 		"rrset=%u infra=%u iter=%u val=%u subnet=%u anchors=%u "
178 		"alloccache=%u globalalloccache=%u me=%u",
179 		(unsigned)total, (unsigned)front, (unsigned)back,
180 		(unsigned)mesh, (unsigned)msg, (unsigned)rrset, (unsigned)infra,
181 		(unsigned)iter, (unsigned)val,
182 		(unsigned)subnet, (unsigned)anch, (unsigned)ac,
183 		(unsigned)superac, (unsigned)me);
184 #else /* no CLIENT_SUBNET */
185 	log_info("Memory conditions: %u front=%u back=%u mesh=%u msg=%u "
186 		"rrset=%u infra=%u iter=%u val=%u anchors=%u "
187 		"alloccache=%u globalalloccache=%u me=%u",
188 		(unsigned)total, (unsigned)front, (unsigned)back,
189 		(unsigned)mesh, (unsigned)msg, (unsigned)rrset,
190 		(unsigned)infra, (unsigned)iter, (unsigned)val, (unsigned)anch,
191 		(unsigned)ac, (unsigned)superac, (unsigned)me);
192 #endif /* CLIENT_SUBNET */
193 	log_info("Total heap memory estimate: %u  total-alloc: %u  "
194 		"total-free: %u", (unsigned)total,
195 		(unsigned)unbound_mem_alloc, (unsigned)unbound_mem_freed);
196 #else /* no UNBOUND_ALLOC_STATS */
197 	size_t val = 0;
198 #ifdef CLIENT_SUBNET
199 	size_t subnet = 0;
200 #endif /* CLIENT_SUBNET */
201 	int i;
202 	if(verbosity < VERB_QUERY)
203 		return;
204 	for(i=0; i<worker->env.mesh->mods.num; i++) {
205 		fptr_ok(fptr_whitelist_mod_get_mem(worker->env.mesh->
206 			mods.mod[i]->get_mem));
207 		if(strcmp(worker->env.mesh->mods.mod[i]->name, "validator")==0)
208 			val += (*worker->env.mesh->mods.mod[i]->get_mem)
209 				(&worker->env, i);
210 #ifdef CLIENT_SUBNET
211 		else if(strcmp(worker->env.mesh->mods.mod[i]->name,
212 			"subnetcache")==0)
213 			subnet += (*worker->env.mesh->mods.mod[i]->get_mem)
214 				(&worker->env, i);
215 #endif /* CLIENT_SUBNET */
216 	}
217 #ifdef CLIENT_SUBNET
218 	verbose(VERB_QUERY, "cache memory msg=%u rrset=%u infra=%u val=%u "
219 		"subnet=%u",
220 		(unsigned)slabhash_get_mem(worker->env.msg_cache),
221 		(unsigned)slabhash_get_mem(&worker->env.rrset_cache->table),
222 		(unsigned)infra_get_mem(worker->env.infra_cache),
223 		(unsigned)val, (unsigned)subnet);
224 #else /* no CLIENT_SUBNET */
225 	verbose(VERB_QUERY, "cache memory msg=%u rrset=%u infra=%u val=%u",
226 		(unsigned)slabhash_get_mem(worker->env.msg_cache),
227 		(unsigned)slabhash_get_mem(&worker->env.rrset_cache->table),
228 		(unsigned)infra_get_mem(worker->env.infra_cache),
229 		(unsigned)val);
230 #endif /* CLIENT_SUBNET */
231 #endif /* UNBOUND_ALLOC_STATS */
232 }
233 
234 void
235 worker_send_cmd(struct worker* worker, enum worker_commands cmd)
236 {
237 	uint32_t c = (uint32_t)htonl(cmd);
238 	if(!tube_write_msg(worker->cmd, (uint8_t*)&c, sizeof(c), 0)) {
239 		log_err("worker send cmd %d failed", (int)cmd);
240 	}
241 }
242 
243 int
244 worker_handle_service_reply(struct comm_point* c, void* arg, int error,
245 	struct comm_reply* reply_info)
246 {
247 	struct outbound_entry* e = (struct outbound_entry*)arg;
248 	struct worker* worker = e->qstate->env->worker;
249 	struct serviced_query *sq = e->qsent;
250 
251 	verbose(VERB_ALGO, "worker svcd callback for qstate %p", e->qstate);
252 	if(error != 0) {
253 		mesh_report_reply(worker->env.mesh, e, reply_info, error);
254 		worker_mem_report(worker, sq);
255 		return 0;
256 	}
257 	/* sanity check. */
258 	if(!LDNS_QR_WIRE(sldns_buffer_begin(c->buffer))
259 		|| LDNS_OPCODE_WIRE(sldns_buffer_begin(c->buffer)) !=
260 			LDNS_PACKET_QUERY
261 		|| LDNS_QDCOUNT(sldns_buffer_begin(c->buffer)) > 1) {
262 		/* error becomes timeout for the module as if this reply
263 		 * never arrived. */
264 		verbose(VERB_ALGO, "worker: bad reply handled as timeout");
265 		mesh_report_reply(worker->env.mesh, e, reply_info,
266 			NETEVENT_TIMEOUT);
267 		worker_mem_report(worker, sq);
268 		return 0;
269 	}
270 	mesh_report_reply(worker->env.mesh, e, reply_info, NETEVENT_NOERROR);
271 	worker_mem_report(worker, sq);
272 	return 0;
273 }
274 
275 /** ratelimit error replies
276  * @param worker: the worker struct with ratelimit counter
277  * @param err: error code that would be wanted.
278  * @return value of err if okay, or -1 if it should be discarded instead.
279  */
280 static int
281 worker_err_ratelimit(struct worker* worker, int err)
282 {
283 	if(worker->err_limit_time == *worker->env.now) {
284 		/* see if limit is exceeded for this second */
285 		if(worker->err_limit_count++ > ERROR_RATELIMIT)
286 			return -1;
287 	} else {
288 		/* new second, new limits */
289 		worker->err_limit_time = *worker->env.now;
290 		worker->err_limit_count = 1;
291 	}
292 	return err;
293 }
294 
295 /**
296  * Structure holding the result of the worker_check_request function.
297  * Based on configuration it could be called up to four times; ideally should
298  * be called once.
299  */
300 struct check_request_result {
301 	int checked;
302 	int value;
303 };
304 /** check request sanity.
305  * @param pkt: the wire packet to examine for sanity.
306  * @param worker: parameters for checking.
307  * @param out: struct to update with the result.
308 */
309 static void
310 worker_check_request(sldns_buffer* pkt, struct worker* worker,
311 	struct check_request_result* out)
312 {
313 	if(out->checked) return;
314 	out->checked = 1;
315 	if(sldns_buffer_limit(pkt) < LDNS_HEADER_SIZE) {
316 		verbose(VERB_QUERY, "request too short, discarded");
317 		out->value = -1;
318 		return;
319 	}
320 	if(sldns_buffer_limit(pkt) > NORMAL_UDP_SIZE &&
321 		worker->daemon->cfg->harden_large_queries) {
322 		verbose(VERB_QUERY, "request too large, discarded");
323 		out->value = -1;
324 		return;
325 	}
326 	if(LDNS_QR_WIRE(sldns_buffer_begin(pkt))) {
327 		verbose(VERB_QUERY, "request has QR bit on, discarded");
328 		out->value = -1;
329 		return;
330 	}
331 	if(LDNS_TC_WIRE(sldns_buffer_begin(pkt))) {
332 		LDNS_TC_CLR(sldns_buffer_begin(pkt));
333 		verbose(VERB_QUERY, "request bad, has TC bit on");
334 		out->value = worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
335 		return;
336 	}
337 	if(LDNS_OPCODE_WIRE(sldns_buffer_begin(pkt)) != LDNS_PACKET_QUERY &&
338 		LDNS_OPCODE_WIRE(sldns_buffer_begin(pkt)) != LDNS_PACKET_NOTIFY) {
339 		verbose(VERB_QUERY, "request unknown opcode %d",
340 			LDNS_OPCODE_WIRE(sldns_buffer_begin(pkt)));
341 		out->value = worker_err_ratelimit(worker, LDNS_RCODE_NOTIMPL);
342 		return;
343 	}
344 	if(LDNS_QDCOUNT(sldns_buffer_begin(pkt)) != 1) {
345 		verbose(VERB_QUERY, "request wrong nr qd=%d",
346 			LDNS_QDCOUNT(sldns_buffer_begin(pkt)));
347 		out->value = worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
348 		return;
349 	}
350 	if(LDNS_ANCOUNT(sldns_buffer_begin(pkt)) != 0 &&
351 		(LDNS_ANCOUNT(sldns_buffer_begin(pkt)) != 1 ||
352 		LDNS_OPCODE_WIRE(sldns_buffer_begin(pkt)) != LDNS_PACKET_NOTIFY)) {
353 		verbose(VERB_QUERY, "request wrong nr an=%d",
354 			LDNS_ANCOUNT(sldns_buffer_begin(pkt)));
355 		out->value = worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
356 		return;
357 	}
358 	if(LDNS_NSCOUNT(sldns_buffer_begin(pkt)) != 0) {
359 		verbose(VERB_QUERY, "request wrong nr ns=%d",
360 			LDNS_NSCOUNT(sldns_buffer_begin(pkt)));
361 		out->value = worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
362 		return;
363 	}
364 	if(LDNS_ARCOUNT(sldns_buffer_begin(pkt)) > 1) {
365 		verbose(VERB_QUERY, "request wrong nr ar=%d",
366 			LDNS_ARCOUNT(sldns_buffer_begin(pkt)));
367 		out->value = worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
368 		return;
369 	}
370 	out->value = 0;
371 	return;
372 }
373 
374 void
375 worker_handle_control_cmd(struct tube* ATTR_UNUSED(tube), uint8_t* msg,
376 	size_t len, int error, void* arg)
377 {
378 	struct worker* worker = (struct worker*)arg;
379 	enum worker_commands cmd;
380 	if(error != NETEVENT_NOERROR) {
381 		free(msg);
382 		if(error == NETEVENT_CLOSED)
383 			comm_base_exit(worker->base);
384 		else	log_info("control event: %d", error);
385 		return;
386 	}
387 	if(len != sizeof(uint32_t)) {
388 		fatal_exit("bad control msg length %d", (int)len);
389 	}
390 	cmd = sldns_read_uint32(msg);
391 	free(msg);
392 	switch(cmd) {
393 	case worker_cmd_quit:
394 		verbose(VERB_ALGO, "got control cmd quit");
395 		comm_base_exit(worker->base);
396 		break;
397 	case worker_cmd_stats:
398 		verbose(VERB_ALGO, "got control cmd stats");
399 		server_stats_reply(worker, 1);
400 		break;
401 	case worker_cmd_stats_noreset:
402 		verbose(VERB_ALGO, "got control cmd stats_noreset");
403 		server_stats_reply(worker, 0);
404 		break;
405 	case worker_cmd_remote:
406 		verbose(VERB_ALGO, "got control cmd remote");
407 		daemon_remote_exec(worker);
408 		break;
409 	default:
410 		log_err("bad command %d", (int)cmd);
411 		break;
412 	}
413 }
414 
415 /** check if a delegation is secure */
416 static enum sec_status
417 check_delegation_secure(struct reply_info *rep)
418 {
419 	/* return smallest security status */
420 	size_t i;
421 	enum sec_status sec = sec_status_secure;
422 	enum sec_status s;
423 	size_t num = rep->an_numrrsets + rep->ns_numrrsets;
424 	/* check if answer and authority are OK */
425 	for(i=0; i<num; i++) {
426 		s = ((struct packed_rrset_data*)rep->rrsets[i]->entry.data)
427 			->security;
428 		if(s < sec)
429 			sec = s;
430 	}
431 	/* in additional, only unchecked triggers revalidation */
432 	for(i=num; i<rep->rrset_count; i++) {
433 		s = ((struct packed_rrset_data*)rep->rrsets[i]->entry.data)
434 			->security;
435 		if(s == sec_status_unchecked)
436 			return s;
437 	}
438 	return sec;
439 }
440 
441 /** remove nonsecure from a delegation referral additional section */
442 static void
443 deleg_remove_nonsecure_additional(struct reply_info* rep)
444 {
445 	/* we can simply edit it, since we are working in the scratch region */
446 	size_t i;
447 	enum sec_status s;
448 
449 	for(i = rep->an_numrrsets+rep->ns_numrrsets; i<rep->rrset_count; i++) {
450 		s = ((struct packed_rrset_data*)rep->rrsets[i]->entry.data)
451 			->security;
452 		if(s != sec_status_secure) {
453 			memmove(rep->rrsets+i, rep->rrsets+i+1,
454 				sizeof(struct ub_packed_rrset_key*)*
455 				(rep->rrset_count - i - 1));
456 			rep->ar_numrrsets--;
457 			rep->rrset_count--;
458 			i--;
459 		}
460 	}
461 }
462 
463 /** answer nonrecursive query from the cache */
464 static int
465 answer_norec_from_cache(struct worker* worker, struct query_info* qinfo,
466 	uint16_t id, uint16_t flags, struct comm_reply* repinfo,
467 	struct edns_data* edns)
468 {
469 	/* for a nonrecursive query return either:
470 	 * 	o an error (servfail; we try to avoid this)
471 	 * 	o a delegation (closest we have; this routine tries that)
472 	 * 	o the answer (checked by answer_from_cache)
473 	 *
474 	 * So, grab a delegation from the rrset cache.
475 	 * Then check if it needs validation, if so, this routine fails,
476 	 * so that iterator can prime and validator can verify rrsets.
477 	 */
478 	uint16_t udpsize = edns->udp_size;
479 	int secure = 0;
480 	time_t timenow = *worker->env.now;
481 	int has_cd_bit = (flags&BIT_CD);
482 	int must_validate = (!has_cd_bit || worker->env.cfg->ignore_cd)
483 		&& worker->env.need_to_validate;
484 	struct dns_msg *msg = NULL;
485 	struct delegpt *dp;
486 
487 	dp = dns_cache_find_delegation(&worker->env, qinfo->qname,
488 		qinfo->qname_len, qinfo->qtype, qinfo->qclass,
489 		worker->scratchpad, &msg, timenow, 0, NULL, 0);
490 	if(!dp) { /* no delegation, need to reprime */
491 		return 0;
492 	}
493 	/* In case we have a local alias, copy it into the delegation message.
494 	 * Shallow copy should be fine, as we'll be done with msg in this
495 	 * function. */
496 	msg->qinfo.local_alias = qinfo->local_alias;
497 	if(must_validate) {
498 		switch(check_delegation_secure(msg->rep)) {
499 		case sec_status_unchecked:
500 			/* some rrsets have not been verified yet, go and
501 			 * let validator do that */
502 			return 0;
503 		case sec_status_bogus:
504 		case sec_status_secure_sentinel_fail:
505 			/* some rrsets are bogus, reply servfail */
506 			edns->edns_version = EDNS_ADVERTISED_VERSION;
507 			edns->udp_size = EDNS_ADVERTISED_SIZE;
508 			edns->ext_rcode = 0;
509 			edns->bits &= EDNS_DO;
510 			if(!inplace_cb_reply_servfail_call(&worker->env, qinfo, NULL,
511 				msg->rep, LDNS_RCODE_SERVFAIL, edns, repinfo, worker->scratchpad,
512 				worker->env.now_tv))
513 					return 0;
514 			/* Attach the cached EDE (RFC8914) */
515 			if(worker->env.cfg->ede &&
516 				msg->rep->reason_bogus != LDNS_EDE_NONE) {
517 				edns_opt_list_append_ede(&edns->opt_list_out,
518 					worker->scratchpad, msg->rep->reason_bogus,
519 					msg->rep->reason_bogus_str);
520 			}
521 			error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
522 				&msg->qinfo, id, flags, edns);
523 			if(worker->stats.extended) {
524 				worker->stats.ans_bogus++;
525 				worker->stats.ans_rcode[LDNS_RCODE_SERVFAIL]++;
526 			}
527 			return 1;
528 		case sec_status_secure:
529 			/* all rrsets are secure */
530 			/* remove non-secure rrsets from the add. section*/
531 			if(worker->env.cfg->val_clean_additional)
532 				deleg_remove_nonsecure_additional(msg->rep);
533 			secure = 1;
534 			break;
535 		case sec_status_indeterminate:
536 		case sec_status_insecure:
537 		default:
538 			/* not secure */
539 			secure = 0;
540 			break;
541 		}
542 	}
543 	/* return this delegation from the cache */
544 	edns->edns_version = EDNS_ADVERTISED_VERSION;
545 	edns->udp_size = EDNS_ADVERTISED_SIZE;
546 	edns->ext_rcode = 0;
547 	edns->bits &= EDNS_DO;
548 	if(worker->env.cfg->disable_edns_do && (edns->bits & EDNS_DO))
549 		edns->edns_present = 0;
550 	if(!inplace_cb_reply_cache_call(&worker->env, qinfo, NULL, msg->rep,
551 		(int)(flags&LDNS_RCODE_MASK), edns, repinfo, worker->scratchpad,
552 		worker->env.now_tv))
553 			return 0;
554 	msg->rep->flags |= BIT_QR|BIT_RA;
555 	/* Attach the cached EDE (RFC8914) if CD bit is set and the answer is
556 	 * bogus. */
557 	if(worker->env.cfg->ede && has_cd_bit &&
558 		(check_delegation_secure(msg->rep) == sec_status_bogus ||
559 		check_delegation_secure(msg->rep) == sec_status_secure_sentinel_fail) &&
560 		msg->rep->reason_bogus != LDNS_EDE_NONE) {
561 		edns_opt_list_append_ede(&edns->opt_list_out,
562 			worker->scratchpad, msg->rep->reason_bogus,
563 			msg->rep->reason_bogus_str);
564 	}
565 	if(!reply_info_answer_encode(&msg->qinfo, msg->rep, id, flags,
566 		repinfo->c->buffer, 0, 1, worker->scratchpad,
567 		udpsize, edns, (int)(edns->bits & EDNS_DO), secure)) {
568 		if(!inplace_cb_reply_servfail_call(&worker->env, qinfo, NULL, NULL,
569 			LDNS_RCODE_SERVFAIL, edns, repinfo, worker->scratchpad,
570 			worker->env.now_tv))
571 				edns->opt_list_inplace_cb_out = NULL;
572 		error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
573 			&msg->qinfo, id, flags, edns);
574 	}
575 	if(worker->stats.extended) {
576 		if(secure) worker->stats.ans_secure++;
577 		server_stats_insrcode(&worker->stats, repinfo->c->buffer);
578 	}
579 	return 1;
580 }
581 
582 /** Apply, if applicable, a response IP action to a cached answer.
583  * If the answer is rewritten as a result of an action, '*encode_repp' will
584  * point to the reply info containing the modified answer.  '*encode_repp' will
585  * be intact otherwise.
586  * It returns 1 on success, 0 otherwise. */
587 static int
588 apply_respip_action(struct worker* worker, const struct query_info* qinfo,
589 	struct respip_client_info* cinfo, struct reply_info* rep,
590 	struct sockaddr_storage* addr, socklen_t addrlen,
591 	struct ub_packed_rrset_key** alias_rrset,
592 	struct reply_info** encode_repp, struct auth_zones* az)
593 {
594 	struct respip_action_info actinfo = {0, 0, 0, 0, NULL, 0, NULL};
595 	actinfo.action = respip_none;
596 
597 	if(qinfo->qtype != LDNS_RR_TYPE_A &&
598 		qinfo->qtype != LDNS_RR_TYPE_AAAA &&
599 		qinfo->qtype != LDNS_RR_TYPE_ANY)
600 		return 1;
601 
602 	if(!respip_rewrite_reply(qinfo, cinfo, rep, encode_repp, &actinfo,
603 		alias_rrset, 0, worker->scratchpad, az, NULL))
604 		return 0;
605 
606 	/* xxx_deny actions mean dropping the reply, unless the original reply
607 	 * was redirected to response-ip data. */
608 	if(actinfo.action == respip_always_deny ||
609 		((actinfo.action == respip_deny ||
610 		actinfo.action == respip_inform_deny) &&
611 		*encode_repp == rep))
612 		*encode_repp = NULL;
613 
614 	/* If address info is returned, it means the action should be an
615 	 * 'inform' variant and the information should be logged. */
616 	if(actinfo.addrinfo) {
617 		respip_inform_print(&actinfo, qinfo->qname,
618 			qinfo->qtype, qinfo->qclass, qinfo->local_alias,
619 			addr, addrlen);
620 
621 		if(worker->stats.extended && actinfo.rpz_used) {
622 			if(actinfo.rpz_disabled)
623 				worker->stats.rpz_action[RPZ_DISABLED_ACTION]++;
624 			if(actinfo.rpz_cname_override)
625 				worker->stats.rpz_action[RPZ_CNAME_OVERRIDE_ACTION]++;
626 			else
627 				worker->stats.rpz_action[
628 					respip_action_to_rpz_action(actinfo.action)]++;
629 		}
630 	}
631 
632 	return 1;
633 }
634 
635 /** answer query from the cache.
636  * Normally, the answer message will be built in repinfo->c->buffer; if the
637  * answer is supposed to be suppressed or the answer is supposed to be an
638  * incomplete CNAME chain, the buffer is explicitly cleared to signal the
639  * caller as such.  In the latter case *partial_rep will point to the incomplete
640  * reply, and this function is (possibly) supposed to be called again with that
641  * *partial_rep value to complete the chain.  In addition, if the query should
642  * be completely dropped, '*need_drop' will be set to 1. */
643 static int
644 answer_from_cache(struct worker* worker, struct query_info* qinfo,
645 	struct respip_client_info* cinfo, int* need_drop, int* is_expired_answer,
646 	int* is_secure_answer, struct ub_packed_rrset_key** alias_rrset,
647 	struct reply_info** partial_repp,
648 	struct reply_info* rep, uint16_t id, uint16_t flags,
649 	struct comm_reply* repinfo, struct edns_data* edns)
650 {
651 	time_t timenow = *worker->env.now;
652 	uint16_t udpsize = edns->udp_size;
653 	struct reply_info* encode_rep = rep;
654 	struct reply_info* partial_rep = *partial_repp;
655 	int has_cd_bit = (flags&BIT_CD);
656 	int must_validate = (!has_cd_bit || worker->env.cfg->ignore_cd)
657 		&& worker->env.need_to_validate;
658 	*partial_repp = NULL;  /* avoid accidental further pass */
659 
660 	/* Check TTL */
661 	if(rep->ttl < timenow) {
662 		/* Check if we need to serve expired now */
663 		if(worker->env.cfg->serve_expired &&
664 			!worker->env.cfg->serve_expired_client_timeout
665 #ifdef USE_CACHEDB
666 			&& !(worker->env.cachedb_enabled &&
667 			  worker->env.cfg->cachedb_check_when_serve_expired)
668 #endif
669 			) {
670 				if(worker->env.cfg->serve_expired_ttl &&
671 					rep->serve_expired_ttl < timenow)
672 					return 0;
673 				/* Ignore expired failure answers */
674 				if(FLAGS_GET_RCODE(rep->flags) !=
675 					LDNS_RCODE_NOERROR &&
676 					FLAGS_GET_RCODE(rep->flags) !=
677 					LDNS_RCODE_NXDOMAIN &&
678 					FLAGS_GET_RCODE(rep->flags) !=
679 					LDNS_RCODE_YXDOMAIN)
680 					return 0;
681 				if(!rrset_array_lock(rep->ref, rep->rrset_count, 0))
682 					return 0;
683 				*is_expired_answer = 1;
684 		} else {
685 			/* the rrsets may have been updated in the meantime.
686 			 * we will refetch the message format from the
687 			 * authoritative server
688 			 */
689 			return 0;
690 		}
691 	} else {
692 		if(!rrset_array_lock(rep->ref, rep->rrset_count, timenow))
693 			return 0;
694 	}
695 	/* locked and ids and ttls are OK. */
696 
697 	/* check CNAME chain (if any) */
698 	if(rep->an_numrrsets > 0 && (rep->rrsets[0]->rk.type ==
699 		htons(LDNS_RR_TYPE_CNAME) || rep->rrsets[0]->rk.type ==
700 		htons(LDNS_RR_TYPE_DNAME))) {
701 		if(!reply_check_cname_chain(qinfo, rep)) {
702 			/* cname chain invalid, redo iterator steps */
703 			verbose(VERB_ALGO, "Cache reply: cname chain broken");
704 			goto bail_out;
705 		}
706 	}
707 	/* check security status of the cached answer */
708 	if(must_validate && (rep->security == sec_status_bogus ||
709 		rep->security == sec_status_secure_sentinel_fail)) {
710 		/* BAD cached */
711 		edns->edns_version = EDNS_ADVERTISED_VERSION;
712 		edns->udp_size = EDNS_ADVERTISED_SIZE;
713 		edns->ext_rcode = 0;
714 		edns->bits &= EDNS_DO;
715 		if(worker->env.cfg->disable_edns_do && (edns->bits & EDNS_DO))
716 			edns->edns_present = 0;
717 		if(!inplace_cb_reply_servfail_call(&worker->env, qinfo, NULL, rep,
718 			LDNS_RCODE_SERVFAIL, edns, repinfo, worker->scratchpad,
719 			worker->env.now_tv))
720 			goto bail_out;
721 		/* Attach the cached EDE (RFC8914) */
722 		if(worker->env.cfg->ede && rep->reason_bogus != LDNS_EDE_NONE) {
723 			edns_opt_list_append_ede(&edns->opt_list_out,
724 					worker->scratchpad, rep->reason_bogus,
725 					rep->reason_bogus_str);
726 		}
727 		error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
728 			qinfo, id, flags, edns);
729 		rrset_array_unlock_touch(worker->env.rrset_cache,
730 			worker->scratchpad, rep->ref, rep->rrset_count);
731 		if(worker->stats.extended) {
732 			worker->stats.ans_bogus ++;
733 			worker->stats.ans_rcode[LDNS_RCODE_SERVFAIL] ++;
734 		}
735 		return 1;
736 	} else if(rep->security == sec_status_unchecked && must_validate) {
737 		verbose(VERB_ALGO, "Cache reply: unchecked entry needs "
738 			"validation");
739 		goto bail_out; /* need to validate cache entry first */
740 	} else if(rep->security == sec_status_secure) {
741 		if(reply_all_rrsets_secure(rep)) {
742 			*is_secure_answer = 1;
743 		} else {
744 			if(must_validate) {
745 				verbose(VERB_ALGO, "Cache reply: secure entry"
746 					" changed status");
747 				goto bail_out; /* rrset changed, re-verify */
748 			}
749 			*is_secure_answer = 0;
750 		}
751 	} else *is_secure_answer = 0;
752 
753 	edns->edns_version = EDNS_ADVERTISED_VERSION;
754 	edns->udp_size = EDNS_ADVERTISED_SIZE;
755 	edns->ext_rcode = 0;
756 	edns->bits &= EDNS_DO;
757 	if(worker->env.cfg->disable_edns_do && (edns->bits & EDNS_DO))
758 		edns->edns_present = 0;
759 	*alias_rrset = NULL; /* avoid confusion if caller set it to non-NULL */
760 	if((worker->daemon->use_response_ip || worker->daemon->use_rpz) &&
761 		!partial_rep && !apply_respip_action(worker, qinfo, cinfo, rep,
762 		&repinfo->client_addr, repinfo->client_addrlen, alias_rrset,
763 		&encode_rep, worker->env.auth_zones)) {
764 		goto bail_out;
765 	} else if(partial_rep &&
766 		!respip_merge_cname(partial_rep, qinfo, rep, cinfo,
767 		must_validate, &encode_rep, worker->scratchpad,
768 		worker->env.auth_zones)) {
769 		goto bail_out;
770 	}
771 	if(encode_rep != rep) {
772 		/* if rewritten, it can't be considered "secure" */
773 		*is_secure_answer = 0;
774 	}
775 	if(!encode_rep || *alias_rrset) {
776 		if(!encode_rep)
777 			*need_drop = 1;
778 		else {
779 			/* If a partial CNAME chain is found, we first need to
780 			 * make a copy of the reply in the scratchpad so we
781 			 * can release the locks and lookup the cache again. */
782 			*partial_repp = reply_info_copy(encode_rep, NULL,
783 				worker->scratchpad);
784 			if(!*partial_repp)
785 				goto bail_out;
786 		}
787 	} else {
788 		if(*is_expired_answer == 1 &&
789 			worker->env.cfg->ede_serve_expired && worker->env.cfg->ede) {
790 			EDNS_OPT_LIST_APPEND_EDE(&edns->opt_list_out,
791 				worker->scratchpad, LDNS_EDE_STALE_ANSWER, "");
792 		}
793 		/* Attach the cached EDE (RFC8914) if CD bit is set and the
794 		 * answer is bogus. */
795 		if(*is_secure_answer == 0 &&
796 			worker->env.cfg->ede && has_cd_bit &&
797 			encode_rep->reason_bogus != LDNS_EDE_NONE) {
798 			edns_opt_list_append_ede(&edns->opt_list_out,
799 				worker->scratchpad, encode_rep->reason_bogus,
800 				encode_rep->reason_bogus_str);
801 		}
802 		if(!inplace_cb_reply_cache_call(&worker->env, qinfo, NULL, encode_rep,
803 			(int)(flags&LDNS_RCODE_MASK), edns, repinfo, worker->scratchpad,
804 			worker->env.now_tv))
805 			goto bail_out;
806 		if(!reply_info_answer_encode(qinfo, encode_rep, id, flags,
807 			repinfo->c->buffer, timenow, 1, worker->scratchpad,
808 			udpsize, edns, (int)(edns->bits & EDNS_DO),
809 			*is_secure_answer)) {
810 			if(!inplace_cb_reply_servfail_call(&worker->env, qinfo,
811 				NULL, NULL, LDNS_RCODE_SERVFAIL, edns, repinfo,
812 				worker->scratchpad, worker->env.now_tv))
813 					edns->opt_list_inplace_cb_out = NULL;
814 			error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
815 				qinfo, id, flags, edns);
816 		}
817 	}
818 	/* cannot send the reply right now, because blocking network syscall
819 	 * is bad while holding locks. */
820 	rrset_array_unlock_touch(worker->env.rrset_cache, worker->scratchpad,
821 		rep->ref, rep->rrset_count);
822 	/* go and return this buffer to the client */
823 	return 1;
824 
825 bail_out:
826 	rrset_array_unlock_touch(worker->env.rrset_cache,
827 		worker->scratchpad, rep->ref, rep->rrset_count);
828 	return 0;
829 }
830 
831 /** Reply to client and perform prefetch to keep cache up to date. */
832 static void
833 reply_and_prefetch(struct worker* worker, struct query_info* qinfo,
834 	uint16_t flags, struct comm_reply* repinfo, time_t leeway, int noreply,
835 	int rpz_passthru, struct edns_option* opt_list)
836 {
837 	(void)opt_list;
838 	/* first send answer to client to keep its latency
839 	 * as small as a cachereply */
840 	if(!noreply) {
841 		if(repinfo->c->tcp_req_info) {
842 			sldns_buffer_copy(
843 				repinfo->c->tcp_req_info->spool_buffer,
844 				repinfo->c->buffer);
845 		}
846 		comm_point_send_reply(repinfo);
847 	}
848 	server_stats_prefetch(&worker->stats, worker);
849 #ifdef CLIENT_SUBNET
850 	/* Check if the subnet module is enabled. In that case pass over the
851 	 * comm_reply information for ECS generation later. The mesh states are
852 	 * unique when subnet is enabled. */
853 	if(modstack_find(&worker->env.mesh->mods, "subnetcache") != -1
854 		&& worker->env.unique_mesh) {
855 		mesh_new_prefetch(worker->env.mesh, qinfo, flags, leeway +
856 			PREFETCH_EXPIRY_ADD, rpz_passthru,
857 			&repinfo->client_addr, opt_list);
858 		return;
859 	}
860 #endif
861 	/* create the prefetch in the mesh as a normal lookup without
862 	 * client addrs waiting, which has the cache blacklisted (to bypass
863 	 * the cache and go to the network for the data). */
864 	/* this (potentially) runs the mesh for the new query */
865 	mesh_new_prefetch(worker->env.mesh, qinfo, flags, leeway +
866 		PREFETCH_EXPIRY_ADD, rpz_passthru, NULL, NULL);
867 }
868 
869 /**
870  * Fill CH class answer into buffer. Keeps query.
871  * @param pkt: buffer
872  * @param str: string to put into text record (<255).
873  * 	array of strings, every string becomes a text record.
874  * @param num: number of strings in array.
875  * @param edns: edns reply information.
876  * @param worker: worker with scratch region.
877  * @param repinfo: reply information for a communication point.
878  */
879 static void
880 chaos_replystr(sldns_buffer* pkt, char** str, int num, struct edns_data* edns,
881 	struct worker* worker, struct comm_reply* repinfo)
882 {
883 	int i;
884 	unsigned int rd = LDNS_RD_WIRE(sldns_buffer_begin(pkt));
885 	unsigned int cd = LDNS_CD_WIRE(sldns_buffer_begin(pkt));
886 	size_t udpsize = edns->udp_size;
887 	edns->edns_version = EDNS_ADVERTISED_VERSION;
888 	edns->udp_size = EDNS_ADVERTISED_SIZE;
889 	edns->bits &= EDNS_DO;
890 	if(!inplace_cb_reply_local_call(&worker->env, NULL, NULL, NULL,
891 		LDNS_RCODE_NOERROR, edns, repinfo, worker->scratchpad,
892 		worker->env.now_tv))
893 			edns->opt_list_inplace_cb_out = NULL;
894 	sldns_buffer_clear(pkt);
895 	sldns_buffer_skip(pkt, (ssize_t)sizeof(uint16_t)); /* skip id */
896 	sldns_buffer_write_u16(pkt, (uint16_t)(BIT_QR|BIT_RA));
897 	if(rd) LDNS_RD_SET(sldns_buffer_begin(pkt));
898 	if(cd) LDNS_CD_SET(sldns_buffer_begin(pkt));
899 	sldns_buffer_write_u16(pkt, 1); /* qdcount */
900 	sldns_buffer_write_u16(pkt, (uint16_t)num); /* ancount */
901 	sldns_buffer_write_u16(pkt, 0); /* nscount */
902 	sldns_buffer_write_u16(pkt, 0); /* arcount */
903 	(void)query_dname_len(pkt); /* skip qname */
904 	sldns_buffer_skip(pkt, (ssize_t)sizeof(uint16_t)); /* skip qtype */
905 	sldns_buffer_skip(pkt, (ssize_t)sizeof(uint16_t)); /* skip qclass */
906 	for(i=0; i<num; i++) {
907 		size_t len = strlen(str[i]);
908 		if(len>255) len=255; /* cap size of TXT record */
909 		if(sldns_buffer_position(pkt)+2+2+2+4+2+1+len+
910 			calc_edns_field_size(edns) > udpsize) {
911 			sldns_buffer_write_u16_at(pkt, 6, i); /* ANCOUNT */
912 			LDNS_TC_SET(sldns_buffer_begin(pkt));
913 			break;
914 		}
915 		sldns_buffer_write_u16(pkt, 0xc00c); /* compr ptr to query */
916 		sldns_buffer_write_u16(pkt, LDNS_RR_TYPE_TXT);
917 		sldns_buffer_write_u16(pkt, LDNS_RR_CLASS_CH);
918 		sldns_buffer_write_u32(pkt, 0); /* TTL */
919 		sldns_buffer_write_u16(pkt, sizeof(uint8_t) + len);
920 		sldns_buffer_write_u8(pkt, len);
921 		sldns_buffer_write(pkt, str[i], len);
922 	}
923 	sldns_buffer_flip(pkt);
924 	if(sldns_buffer_capacity(pkt) >=
925 		sldns_buffer_limit(pkt)+calc_edns_field_size(edns))
926 		attach_edns_record(pkt, edns);
927 }
928 
929 /** Reply with one string */
930 static void
931 chaos_replyonestr(sldns_buffer* pkt, const char* str, struct edns_data* edns,
932 	struct worker* worker, struct comm_reply* repinfo)
933 {
934 	chaos_replystr(pkt, (char**)&str, 1, edns, worker, repinfo);
935 }
936 
937 /**
938  * Create CH class trustanchor answer.
939  * @param pkt: buffer
940  * @param edns: edns reply information.
941  * @param w: worker with scratch region.
942  * @param repinfo: reply information for a communication point.
943  */
944 static void
945 chaos_trustanchor(sldns_buffer* pkt, struct edns_data* edns, struct worker* w,
946 	struct comm_reply* repinfo)
947 {
948 #define TA_RESPONSE_MAX_TXT 16 /* max number of TXT records */
949 #define TA_RESPONSE_MAX_TAGS 32 /* max number of tags printed per zone */
950 	char* str_array[TA_RESPONSE_MAX_TXT];
951 	uint16_t tags[TA_RESPONSE_MAX_TAGS];
952 	int num = 0;
953 	struct trust_anchor* ta;
954 
955 	if(!w->env.need_to_validate) {
956 		/* no validator module, reply no trustanchors */
957 		chaos_replystr(pkt, NULL, 0, edns, w, repinfo);
958 		return;
959 	}
960 
961 	/* fill the string with contents */
962 	lock_basic_lock(&w->env.anchors->lock);
963 	RBTREE_FOR(ta, struct trust_anchor*, w->env.anchors->tree) {
964 		char* str;
965 		size_t i, numtag, str_len = 255;
966 		if(num == TA_RESPONSE_MAX_TXT) continue;
967 		str = (char*)regional_alloc(w->scratchpad, str_len);
968 		if(!str) continue;
969 		lock_basic_lock(&ta->lock);
970 		numtag = anchor_list_keytags(ta, tags, TA_RESPONSE_MAX_TAGS);
971 		if(numtag == 0) {
972 			/* empty, insecure point */
973 			lock_basic_unlock(&ta->lock);
974 			continue;
975 		}
976 		str_array[num] = str;
977 		num++;
978 
979 		/* spool name of anchor */
980 		(void)sldns_wire2str_dname_buf(ta->name, ta->namelen, str, str_len);
981 		str_len -= strlen(str); str += strlen(str);
982 		/* spool tags */
983 		for(i=0; i<numtag; i++) {
984 			snprintf(str, str_len, " %u", (unsigned)tags[i]);
985 			str_len -= strlen(str); str += strlen(str);
986 		}
987 		lock_basic_unlock(&ta->lock);
988 	}
989 	lock_basic_unlock(&w->env.anchors->lock);
990 
991 	chaos_replystr(pkt, str_array, num, edns, w, repinfo);
992 	regional_free_all(w->scratchpad);
993 }
994 
995 /**
996  * Answer CH class queries.
997  * @param w: worker
998  * @param qinfo: query info. Pointer into packet buffer.
999  * @param edns: edns info from query.
1000  * @param repinfo: reply information for a communication point.
1001  * @param pkt: packet buffer.
1002  * @return: true if a reply is to be sent.
1003  */
1004 static int
1005 answer_chaos(struct worker* w, struct query_info* qinfo,
1006 	struct edns_data* edns, struct comm_reply* repinfo, sldns_buffer* pkt)
1007 {
1008 	struct config_file* cfg = w->env.cfg;
1009 	if(qinfo->qtype != LDNS_RR_TYPE_ANY && qinfo->qtype != LDNS_RR_TYPE_TXT)
1010 		return 0;
1011 	if(query_dname_compare(qinfo->qname,
1012 		(uint8_t*)"\002id\006server") == 0 ||
1013 		query_dname_compare(qinfo->qname,
1014 		(uint8_t*)"\010hostname\004bind") == 0)
1015 	{
1016 		if(cfg->hide_identity)
1017 			return 0;
1018 		if(cfg->identity==NULL || cfg->identity[0]==0) {
1019 			char buf[MAXHOSTNAMELEN+1];
1020 			if (gethostname(buf, MAXHOSTNAMELEN) == 0) {
1021 				buf[MAXHOSTNAMELEN] = 0;
1022 				chaos_replyonestr(pkt, buf, edns, w, repinfo);
1023 			} else 	{
1024 				log_err("gethostname: %s", strerror(errno));
1025 				chaos_replyonestr(pkt, "no hostname", edns, w, repinfo);
1026 			}
1027 		}
1028 		else 	chaos_replyonestr(pkt, cfg->identity, edns, w, repinfo);
1029 		return 1;
1030 	}
1031 	if(query_dname_compare(qinfo->qname,
1032 		(uint8_t*)"\007version\006server") == 0 ||
1033 		query_dname_compare(qinfo->qname,
1034 		(uint8_t*)"\007version\004bind") == 0)
1035 	{
1036 		if(cfg->hide_version)
1037 			return 0;
1038 		if(cfg->version==NULL || cfg->version[0]==0)
1039 			chaos_replyonestr(pkt, PACKAGE_STRING, edns, w, repinfo);
1040 		else 	chaos_replyonestr(pkt, cfg->version, edns, w, repinfo);
1041 		return 1;
1042 	}
1043 	if(query_dname_compare(qinfo->qname,
1044 		(uint8_t*)"\013trustanchor\007unbound") == 0)
1045 	{
1046 		if(cfg->hide_trustanchor)
1047 			return 0;
1048 		chaos_trustanchor(pkt, edns, w, repinfo);
1049 		return 1;
1050 	}
1051 
1052 	return 0;
1053 }
1054 
1055 /**
1056  * Answer notify queries.  These are notifies for authoritative zones,
1057  * the reply is an ack that the notify has been received.  We need to check
1058  * access permission here.
1059  * @param w: worker
1060  * @param qinfo: query info. Pointer into packet buffer.
1061  * @param edns: edns info from query.
1062  * @param addr: client address.
1063  * @param addrlen: client address length.
1064  * @param pkt: packet buffer.
1065  */
1066 static void
1067 answer_notify(struct worker* w, struct query_info* qinfo,
1068 	struct edns_data* edns, sldns_buffer* pkt,
1069 	struct sockaddr_storage* addr, socklen_t addrlen)
1070 {
1071 	int refused = 0;
1072 	int rcode = LDNS_RCODE_NOERROR;
1073 	uint32_t serial = 0;
1074 	int has_serial;
1075 	if(!w->env.auth_zones) return;
1076 	has_serial = auth_zone_parse_notify_serial(pkt, &serial);
1077 	if(auth_zones_notify(w->env.auth_zones, &w->env, qinfo->qname,
1078 		qinfo->qname_len, qinfo->qclass, addr,
1079 		addrlen, has_serial, serial, &refused)) {
1080 		rcode = LDNS_RCODE_NOERROR;
1081 	} else {
1082 		if(refused)
1083 			rcode = LDNS_RCODE_REFUSED;
1084 		else	rcode = LDNS_RCODE_SERVFAIL;
1085 	}
1086 
1087 	if(verbosity >= VERB_DETAIL) {
1088 		char buf[380];
1089 		char zname[255+1];
1090 		char sr[25];
1091 		dname_str(qinfo->qname, zname);
1092 		sr[0]=0;
1093 		if(has_serial)
1094 			snprintf(sr, sizeof(sr), "serial %u ",
1095 				(unsigned)serial);
1096 		if(rcode == LDNS_RCODE_REFUSED)
1097 			snprintf(buf, sizeof(buf),
1098 				"refused NOTIFY %sfor %s from", sr, zname);
1099 		else if(rcode == LDNS_RCODE_SERVFAIL)
1100 			snprintf(buf, sizeof(buf),
1101 				"servfail for NOTIFY %sfor %s from", sr, zname);
1102 		else	snprintf(buf, sizeof(buf),
1103 				"received NOTIFY %sfor %s from", sr, zname);
1104 		log_addr(VERB_DETAIL, buf, addr, addrlen);
1105 	}
1106 	edns->edns_version = EDNS_ADVERTISED_VERSION;
1107 	edns->udp_size = EDNS_ADVERTISED_SIZE;
1108 	edns->ext_rcode = 0;
1109 	edns->bits &= EDNS_DO;
1110 	error_encode(pkt, rcode, qinfo,
1111 		*(uint16_t*)(void *)sldns_buffer_begin(pkt),
1112 		sldns_buffer_read_u16_at(pkt, 2), edns);
1113 	LDNS_OPCODE_SET(sldns_buffer_begin(pkt), LDNS_PACKET_NOTIFY);
1114 }
1115 
1116 static int
1117 deny_refuse(struct comm_point* c, enum acl_access acl,
1118 	enum acl_access deny, enum acl_access refuse,
1119 	struct worker* worker, struct comm_reply* repinfo,
1120 	struct acl_addr* acladdr, int ede,
1121 	struct check_request_result* check_result)
1122 {
1123 	if(acl == deny) {
1124 		if(verbosity >= VERB_ALGO) {
1125 			log_acl_action("dropped", &repinfo->client_addr,
1126 				repinfo->client_addrlen, acl, acladdr);
1127 			log_buf(VERB_ALGO, "dropped", c->buffer);
1128 		}
1129 		comm_point_drop_reply(repinfo);
1130 		if(worker->stats.extended)
1131 			worker->stats.unwanted_queries++;
1132 		return 0;
1133 	} else if(acl == refuse) {
1134 		size_t opt_rr_mark;
1135 
1136 		if(verbosity >= VERB_ALGO) {
1137 			log_acl_action("refused", &repinfo->client_addr,
1138 				repinfo->client_addrlen, acl, acladdr);
1139 			log_buf(VERB_ALGO, "refuse", c->buffer);
1140 		}
1141 
1142 		if(worker->stats.extended)
1143 			worker->stats.unwanted_queries++;
1144 		worker_check_request(c->buffer, worker, check_result);
1145 		if(check_result->value != 0) {
1146 			if(check_result->value != -1) {
1147 				LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1148 				LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1149 					check_result->value);
1150 				return 1;
1151 			}
1152 			comm_point_drop_reply(repinfo);
1153 			return 0;
1154 		}
1155 		/* worker_check_request() above guarantees that the buffer contains at
1156 		 * least a header and that qdcount == 1
1157 		 */
1158 		log_assert(sldns_buffer_limit(c->buffer) >= LDNS_HEADER_SIZE
1159 			&& LDNS_QDCOUNT(sldns_buffer_begin(c->buffer)) == 1);
1160 
1161 		sldns_buffer_set_position(c->buffer, LDNS_HEADER_SIZE); /* skip header */
1162 
1163 		/* check additional section is present and that we respond with EDEs */
1164 		if(LDNS_ARCOUNT(sldns_buffer_begin(c->buffer)) != 1
1165 			|| !ede) {
1166 			LDNS_QDCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1167 			LDNS_ANCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1168 			LDNS_NSCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1169 			LDNS_ARCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1170 			LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1171 			LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1172 				LDNS_RCODE_REFUSED);
1173 			sldns_buffer_set_position(c->buffer, LDNS_HEADER_SIZE);
1174 			sldns_buffer_flip(c->buffer);
1175 			return 1;
1176 		}
1177 
1178 		if (!query_dname_len(c->buffer)) {
1179 			LDNS_QDCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1180 			LDNS_ANCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1181 			LDNS_NSCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1182 			LDNS_ARCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1183 			LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1184 			LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1185 				LDNS_RCODE_FORMERR);
1186 			sldns_buffer_set_position(c->buffer, LDNS_HEADER_SIZE);
1187 			sldns_buffer_flip(c->buffer);
1188 			return 1;
1189 		}
1190 		/* space available for query type and class? */
1191 		if (sldns_buffer_remaining(c->buffer) < 2 * sizeof(uint16_t)) {
1192                         LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1193                         LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1194 				 LDNS_RCODE_FORMERR);
1195 			LDNS_QDCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1196 			LDNS_ANCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1197 			LDNS_NSCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1198 			LDNS_ARCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1199 			sldns_buffer_set_position(c->buffer, LDNS_HEADER_SIZE);
1200                         sldns_buffer_flip(c->buffer);
1201 			return 1;
1202 		}
1203 		LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1204 		LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1205 			LDNS_RCODE_REFUSED);
1206 
1207 		sldns_buffer_skip(c->buffer, (ssize_t)sizeof(uint16_t)); /* skip qtype */
1208 
1209 		sldns_buffer_skip(c->buffer, (ssize_t)sizeof(uint16_t)); /* skip qclass */
1210 
1211 		/* The OPT RR to be returned should come directly after
1212 		 * the query, so mark this spot.
1213 		 */
1214 		opt_rr_mark = sldns_buffer_position(c->buffer);
1215 
1216 		/* Skip through the RR records */
1217 		if(LDNS_ANCOUNT(sldns_buffer_begin(c->buffer)) != 0 ||
1218 			LDNS_NSCOUNT(sldns_buffer_begin(c->buffer)) != 0) {
1219 			if(!skip_pkt_rrs(c->buffer,
1220 				((int)LDNS_ANCOUNT(sldns_buffer_begin(c->buffer)))+
1221 				((int)LDNS_NSCOUNT(sldns_buffer_begin(c->buffer))))) {
1222 				LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1223 					LDNS_RCODE_FORMERR);
1224 				LDNS_ANCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1225 				LDNS_NSCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1226 				LDNS_ARCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1227 				sldns_buffer_set_position(c->buffer, opt_rr_mark);
1228 				sldns_buffer_flip(c->buffer);
1229 				return 1;
1230 			}
1231 		}
1232 		/* Do we have a valid OPT RR here? If not return REFUSED (could be a valid TSIG or something so no FORMERR) */
1233 		/* domain name must be the root of length 1. */
1234 		if(sldns_buffer_remaining(c->buffer) < 1 || *sldns_buffer_current(c->buffer) != 0) {
1235 			LDNS_ANCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1236 			LDNS_NSCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1237 			LDNS_ARCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1238 			sldns_buffer_set_position(c->buffer, opt_rr_mark);
1239 			sldns_buffer_flip(c->buffer);
1240 			return 1;
1241 		} else {
1242 			sldns_buffer_skip(c->buffer, 1); /* skip root label */
1243 		}
1244 		if(sldns_buffer_remaining(c->buffer) < 2 ||
1245 			sldns_buffer_read_u16(c->buffer) != LDNS_RR_TYPE_OPT) {
1246 			LDNS_ANCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1247 			LDNS_NSCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1248 			LDNS_ARCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1249 			sldns_buffer_set_position(c->buffer, opt_rr_mark);
1250 			sldns_buffer_flip(c->buffer);
1251 			return 1;
1252 		}
1253 		/* Write OPT RR directly after the query,
1254 		 * so without the (possibly skipped) Answer and NS RRs
1255 		 */
1256 		LDNS_ANCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1257 		LDNS_NSCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1258 		sldns_buffer_clear(c->buffer); /* reset write limit */
1259 		sldns_buffer_set_position(c->buffer, opt_rr_mark);
1260 
1261 		/* Check if OPT record can be written
1262 		 * 17 == root label (1) + RR type (2) + UDP Size (2)
1263 		 *     + Fields (4) + rdata len (2) + EDE Option code (2)
1264 		 *     + EDE Option length (2) + EDE info-code (2)
1265 		 */
1266 		if (sldns_buffer_available(c->buffer, 17) == 0) {
1267 			LDNS_ARCOUNT_SET(sldns_buffer_begin(c->buffer), 0);
1268 			sldns_buffer_flip(c->buffer);
1269 			return 1;
1270 		}
1271 
1272 		LDNS_ARCOUNT_SET(sldns_buffer_begin(c->buffer), 1);
1273 
1274 		/* root label */
1275 		sldns_buffer_write_u8(c->buffer, 0);
1276 		sldns_buffer_write_u16(c->buffer, LDNS_RR_TYPE_OPT);
1277 		sldns_buffer_write_u16(c->buffer, EDNS_ADVERTISED_SIZE);
1278 
1279 		/* write OPT Record TTL Field */
1280 		sldns_buffer_write_u32(c->buffer, 0);
1281 
1282 		/* write rdata len: EDE option + length + info-code */
1283 		sldns_buffer_write_u16(c->buffer, 6);
1284 
1285 		/* write OPTIONS; add EDE option code */
1286 		sldns_buffer_write_u16(c->buffer, LDNS_EDNS_EDE);
1287 
1288 		/* write single EDE option length (for just 1 info-code) */
1289 		sldns_buffer_write_u16(c->buffer, 2);
1290 
1291 		/* write single EDE info-code */
1292 		sldns_buffer_write_u16(c->buffer, LDNS_EDE_PROHIBITED);
1293 
1294 		sldns_buffer_flip(c->buffer);
1295 
1296 		verbose(VERB_ALGO, "attached EDE code: %d", LDNS_EDE_PROHIBITED);
1297 
1298 		return 1;
1299 
1300 	}
1301 
1302 	return -1;
1303 }
1304 
1305 static int
1306 deny_refuse_all(struct comm_point* c, enum acl_access* acl,
1307 	struct worker* worker, struct comm_reply* repinfo,
1308 	struct acl_addr** acladdr, int ede, int check_proxy,
1309 	struct check_request_result* check_result)
1310 {
1311 	if(check_proxy) {
1312 		*acladdr = acl_addr_lookup(worker->daemon->acl,
1313 			&repinfo->remote_addr, repinfo->remote_addrlen);
1314 	} else {
1315 		*acladdr = acl_addr_lookup(worker->daemon->acl,
1316 			&repinfo->client_addr, repinfo->client_addrlen);
1317 	}
1318 	/* If there is no ACL based on client IP use the interface ACL. */
1319 	if(!(*acladdr) && c->socket) {
1320 		*acladdr = c->socket->acl;
1321 	}
1322 	*acl = acl_get_control(*acladdr);
1323 	return deny_refuse(c, *acl, acl_deny, acl_refuse, worker, repinfo,
1324 		*acladdr, ede, check_result);
1325 }
1326 
1327 static int
1328 deny_refuse_non_local(struct comm_point* c, enum acl_access acl,
1329 	struct worker* worker, struct comm_reply* repinfo,
1330 	struct acl_addr* acladdr, int ede,
1331 	struct check_request_result* check_result)
1332 {
1333 	return deny_refuse(c, acl, acl_deny_non_local, acl_refuse_non_local,
1334 		worker, repinfo, acladdr, ede, check_result);
1335 }
1336 
1337 /* Check if the query is blocked by source IP rate limiting.
1338  * Returns 1 if it passes the check, 0 otherwise. */
1339 static int
1340 check_ip_ratelimit(struct worker* worker, struct sockaddr_storage* addr,
1341 	socklen_t addrlen, int has_cookie, sldns_buffer* pkt)
1342 {
1343 	if(!infra_ip_ratelimit_inc(worker->env.infra_cache, addr, addrlen,
1344 			*worker->env.now, has_cookie,
1345 			worker->env.cfg->ip_ratelimit_backoff, pkt)) {
1346 		/* See if we can pass through with slip factor */
1347 		if(!has_cookie && worker->env.cfg->ip_ratelimit_factor != 0 &&
1348 			ub_random_max(worker->env.rnd,
1349 			worker->env.cfg->ip_ratelimit_factor) == 0) {
1350 			char addrbuf[128];
1351 			addr_to_str(addr, addrlen, addrbuf, sizeof(addrbuf));
1352 			verbose(VERB_QUERY, "ip_ratelimit allowed through for "
1353 				"ip address %s because of slip in "
1354 				"ip_ratelimit_factor", addrbuf);
1355 			return 1;
1356 		}
1357 		return 0;
1358 	}
1359 	return 1;
1360 }
1361 
1362 int
1363 worker_handle_request(struct comm_point* c, void* arg, int error,
1364 	struct comm_reply* repinfo)
1365 {
1366 	struct worker* worker = (struct worker*)arg;
1367 	int ret;
1368 	hashvalue_type h;
1369 	struct lruhash_entry* e;
1370 	struct query_info qinfo;
1371 	struct edns_data edns;
1372 	struct edns_option* original_edns_list = NULL;
1373 	enum acl_access acl;
1374 	struct acl_addr* acladdr;
1375 	int pre_edns_ip_ratelimit = 1;
1376 	int rc = 0;
1377 	int need_drop = 0;
1378 	int is_expired_answer = 0;
1379 	int is_secure_answer = 0;
1380 	int rpz_passthru = 0;
1381 	long long wait_queue_time = 0;
1382 	/* We might have to chase a CNAME chain internally, in which case
1383 	 * we'll have up to two replies and combine them to build a complete
1384 	 * answer.  These variables control this case. */
1385 	struct ub_packed_rrset_key* alias_rrset = NULL;
1386 	struct reply_info* partial_rep = NULL;
1387 	struct query_info* lookup_qinfo = &qinfo;
1388 	struct query_info qinfo_tmp; /* placeholder for lookup_qinfo */
1389 	struct respip_client_info* cinfo = NULL, cinfo_tmp;
1390 	struct timeval wait_time;
1391 	struct check_request_result check_result = {0,0};
1392 	memset(&qinfo, 0, sizeof(qinfo));
1393 
1394 	if((error != NETEVENT_NOERROR && error != NETEVENT_DONE)|| !repinfo) {
1395 		/* some bad tcp query DNS formats give these error calls */
1396 		verbose(VERB_ALGO, "handle request called with err=%d", error);
1397 		return 0;
1398 	}
1399 
1400 	if (worker->env.cfg->sock_queue_timeout && timeval_isset(&c->recv_tv)) {
1401 		timeval_subtract(&wait_time, worker->env.now_tv, &c->recv_tv);
1402 		wait_queue_time = wait_time.tv_sec * 1000000 +  wait_time.tv_usec;
1403 		if (worker->stats.max_query_time_us < wait_queue_time)
1404 			worker->stats.max_query_time_us = wait_queue_time;
1405 		if(wait_queue_time >
1406 			(long long)(worker->env.cfg->sock_queue_timeout * 1000000)) {
1407 			/* count and drop queries that were sitting in the socket queue too long */
1408 			worker->stats.num_queries_timed_out++;
1409 			return 0;
1410 		}
1411 	}
1412 
1413 #ifdef USE_DNSCRYPT
1414 	repinfo->max_udp_size = worker->daemon->cfg->max_udp_size;
1415 	if(!dnsc_handle_curved_request(worker->daemon->dnscenv, repinfo)) {
1416 		worker->stats.num_query_dnscrypt_crypted_malformed++;
1417 		return 0;
1418 	}
1419 	if(c->dnscrypt && !repinfo->is_dnscrypted) {
1420 		char buf[LDNS_MAX_DOMAINLEN+1];
1421 		/* Check if this is unencrypted and asking for certs */
1422 		worker_check_request(c->buffer, worker, &check_result);
1423 		if(check_result.value != 0) {
1424 			verbose(VERB_ALGO,
1425 				"dnscrypt: worker check request: bad query.");
1426 			log_addr(VERB_CLIENT,"from",&repinfo->client_addr,
1427 				repinfo->client_addrlen);
1428 			comm_point_drop_reply(repinfo);
1429 			return 0;
1430 		}
1431 		if(!query_info_parse(&qinfo, c->buffer)) {
1432 			verbose(VERB_ALGO,
1433 				"dnscrypt: worker parse request: formerror.");
1434 			log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1435 				repinfo->client_addrlen);
1436 			comm_point_drop_reply(repinfo);
1437 			return 0;
1438 		}
1439 		dname_str(qinfo.qname, buf);
1440 		if(!(qinfo.qtype == LDNS_RR_TYPE_TXT &&
1441 			strcasecmp(buf,
1442 			worker->daemon->dnscenv->provider_name) == 0)) {
1443 			verbose(VERB_ALGO,
1444 				"dnscrypt: not TXT \"%s\". Received: %s \"%s\"",
1445 				worker->daemon->dnscenv->provider_name,
1446 				sldns_rr_descript(qinfo.qtype)->_name,
1447 				buf);
1448 			comm_point_drop_reply(repinfo);
1449 			worker->stats.num_query_dnscrypt_cleartext++;
1450 			return 0;
1451 		}
1452 		worker->stats.num_query_dnscrypt_cert++;
1453 		sldns_buffer_rewind(c->buffer);
1454 	} else if(c->dnscrypt && repinfo->is_dnscrypted) {
1455 		worker->stats.num_query_dnscrypt_crypted++;
1456 	}
1457 #endif
1458 #ifdef USE_DNSTAP
1459 	/*
1460 	 * sending src (client)/dst (local service) addresses over DNSTAP from incoming request handler
1461 	 */
1462 	if(worker->dtenv.log_client_query_messages) {
1463 		log_addr(VERB_ALGO, "request from client", &repinfo->client_addr, repinfo->client_addrlen);
1464 		log_addr(VERB_ALGO, "to local addr", (void*)repinfo->c->socket->addr, repinfo->c->socket->addrlen);
1465 		dt_msg_send_client_query(&worker->dtenv, &repinfo->client_addr, (void*)repinfo->c->socket->addr, c->type, c->ssl, c->buffer,
1466 		((worker->env.cfg->sock_queue_timeout && timeval_isset(&c->recv_tv))?&c->recv_tv:NULL));
1467 	}
1468 #endif
1469 	/* Check deny/refuse ACLs */
1470 	if(repinfo->is_proxied) {
1471 		if((ret=deny_refuse_all(c, &acl, worker, repinfo, &acladdr,
1472 			worker->env.cfg->ede, 1, &check_result)) != -1) {
1473 			if(ret == 1)
1474 				goto send_reply;
1475 			return ret;
1476 		}
1477 	}
1478 	if((ret=deny_refuse_all(c, &acl, worker, repinfo, &acladdr,
1479 		worker->env.cfg->ede, 0, &check_result)) != -1) {
1480 		if(ret == 1)
1481 			goto send_reply;
1482 		return ret;
1483 	}
1484 
1485 	worker_check_request(c->buffer, worker, &check_result);
1486 	if(check_result.value != 0) {
1487 		verbose(VERB_ALGO, "worker check request: bad query.");
1488 		log_addr(VERB_CLIENT,"from",&repinfo->client_addr, repinfo->client_addrlen);
1489 		if(check_result.value != -1) {
1490 			LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1491 			LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1492 				check_result.value);
1493 			return 1;
1494 		}
1495 		comm_point_drop_reply(repinfo);
1496 		return 0;
1497 	}
1498 
1499 	worker->stats.num_queries++;
1500 	pre_edns_ip_ratelimit = !worker->env.cfg->do_answer_cookie
1501 		|| sldns_buffer_limit(c->buffer) < LDNS_HEADER_SIZE
1502 		|| LDNS_ARCOUNT(sldns_buffer_begin(c->buffer)) == 0;
1503 
1504 	/* If the IP rate limiting check needs extra EDNS information (e.g.,
1505 	 * DNS Cookies) postpone the check until after EDNS is parsed. */
1506 	if(pre_edns_ip_ratelimit) {
1507 		/* NOTE: we always check the repinfo->client_address.
1508 		 *       IP ratelimiting is implicitly disabled for proxies. */
1509 		if(!check_ip_ratelimit(worker, &repinfo->client_addr,
1510 			repinfo->client_addrlen, 0, c->buffer)) {
1511 			worker->stats.num_queries_ip_ratelimited++;
1512 			comm_point_drop_reply(repinfo);
1513 			return 0;
1514 		}
1515 	}
1516 
1517 	if(!query_info_parse(&qinfo, c->buffer)) {
1518 		verbose(VERB_ALGO, "worker parse request: formerror.");
1519 		log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1520 			repinfo->client_addrlen);
1521 		memset(&qinfo, 0, sizeof(qinfo)); /* zero qinfo.qname */
1522 		if(worker_err_ratelimit(worker, LDNS_RCODE_FORMERR) == -1) {
1523 			comm_point_drop_reply(repinfo);
1524 			return 0;
1525 		}
1526 		sldns_buffer_rewind(c->buffer);
1527 		LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1528 		LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1529 			LDNS_RCODE_FORMERR);
1530 		goto send_reply;
1531 	}
1532 	if(worker->env.cfg->log_queries) {
1533 		char ip[128];
1534 		addr_to_str(&repinfo->client_addr, repinfo->client_addrlen, ip, sizeof(ip));
1535 		log_query_in(ip, qinfo.qname, qinfo.qtype, qinfo.qclass);
1536 	}
1537 	if(qinfo.qtype == LDNS_RR_TYPE_AXFR ||
1538 		qinfo.qtype == LDNS_RR_TYPE_IXFR) {
1539 		verbose(VERB_ALGO, "worker request: refused zone transfer.");
1540 		log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1541 			repinfo->client_addrlen);
1542 		sldns_buffer_rewind(c->buffer);
1543 		LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1544 		LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1545 			LDNS_RCODE_REFUSED);
1546 		if(worker->stats.extended) {
1547 			worker->stats.qtype[qinfo.qtype]++;
1548 		}
1549 		goto send_reply;
1550 	}
1551 	if(qinfo.qtype == LDNS_RR_TYPE_OPT ||
1552 		qinfo.qtype == LDNS_RR_TYPE_TSIG ||
1553 		qinfo.qtype == LDNS_RR_TYPE_TKEY ||
1554 		qinfo.qtype == LDNS_RR_TYPE_MAILA ||
1555 		qinfo.qtype == LDNS_RR_TYPE_MAILB ||
1556 		(qinfo.qtype >= 128 && qinfo.qtype <= 248)) {
1557 		verbose(VERB_ALGO, "worker request: formerror for meta-type.");
1558 		log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1559 			repinfo->client_addrlen);
1560 		if(worker_err_ratelimit(worker, LDNS_RCODE_FORMERR) == -1) {
1561 			comm_point_drop_reply(repinfo);
1562 			return 0;
1563 		}
1564 		sldns_buffer_rewind(c->buffer);
1565 		LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1566 		LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1567 			LDNS_RCODE_FORMERR);
1568 		if(worker->stats.extended) {
1569 			worker->stats.qtype[qinfo.qtype]++;
1570 		}
1571 		goto send_reply;
1572 	}
1573 	if((ret=parse_edns_from_query_pkt(
1574 			c->buffer, &edns, worker->env.cfg, c, repinfo,
1575 			(worker->env.now ? *worker->env.now : time(NULL)),
1576 			worker->scratchpad,
1577 			worker->daemon->cookie_secrets)) != 0) {
1578 		struct edns_data reply_edns;
1579 		verbose(VERB_ALGO, "worker parse edns: formerror.");
1580 		log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1581 			repinfo->client_addrlen);
1582 		memset(&reply_edns, 0, sizeof(reply_edns));
1583 		reply_edns.edns_present = 1;
1584 		error_encode(c->buffer, ret, &qinfo,
1585 			*(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
1586 			sldns_buffer_read_u16_at(c->buffer, 2), &reply_edns);
1587 		regional_free_all(worker->scratchpad);
1588 		goto send_reply;
1589 	}
1590 	if(edns.edns_present) {
1591 		if(edns.edns_version != 0) {
1592 			edns.opt_list_in = NULL;
1593 			edns.opt_list_out = NULL;
1594 			edns.opt_list_inplace_cb_out = NULL;
1595 			verbose(VERB_ALGO, "query with bad edns version.");
1596 			log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1597 				repinfo->client_addrlen);
1598 			extended_error_encode(c->buffer, EDNS_RCODE_BADVERS, &qinfo,
1599 				*(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
1600 				sldns_buffer_read_u16_at(c->buffer, 2), 0, &edns);
1601 			regional_free_all(worker->scratchpad);
1602 			goto send_reply;
1603 		}
1604 		if(edns.udp_size < NORMAL_UDP_SIZE &&
1605 		   worker->daemon->cfg->harden_short_bufsize) {
1606 			verbose(VERB_QUERY, "worker request: EDNS bufsize %d ignored",
1607 				(int)edns.udp_size);
1608 			log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1609 				repinfo->client_addrlen);
1610 			edns.udp_size = NORMAL_UDP_SIZE;
1611 		}
1612 	}
1613 
1614 	/* Get stats for cookies */
1615 	server_stats_downstream_cookie(&worker->stats, &edns);
1616 
1617 	/* If the IP rate limiting check was postponed, check now. */
1618 	if(!pre_edns_ip_ratelimit) {
1619 		/* NOTE: we always check the repinfo->client_address.
1620 		 *       IP ratelimiting is implicitly disabled for proxies. */
1621 		if(!check_ip_ratelimit(worker, &repinfo->client_addr,
1622 			repinfo->client_addrlen, edns.cookie_valid,
1623 			c->buffer)) {
1624 			worker->stats.num_queries_ip_ratelimited++;
1625 			comm_point_drop_reply(repinfo);
1626 			return 0;
1627 		}
1628 	}
1629 
1630 	/* "if, else if" sequence below deals with downstream DNS Cookies */
1631 	if(acl != acl_allow_cookie)
1632 		; /* pass; No cookie downstream processing whatsoever */
1633 
1634 	else if(edns.cookie_valid)
1635 		; /* pass; Valid cookie is good! */
1636 
1637 	else if(c->type != comm_udp)
1638 		; /* pass; Stateful transport */
1639 
1640 	else if(edns.cookie_present) {
1641 		/* Cookie present, but not valid: Cookie was bad! */
1642 		extended_error_encode(c->buffer,
1643 			LDNS_EXT_RCODE_BADCOOKIE, &qinfo,
1644 			*(uint16_t*)(void *)
1645 			sldns_buffer_begin(c->buffer),
1646 			sldns_buffer_read_u16_at(c->buffer, 2),
1647 			0, &edns);
1648 		regional_free_all(worker->scratchpad);
1649 		goto send_reply;
1650 	} else {
1651 		/* Cookie required, but no cookie present on UDP */
1652 		verbose(VERB_ALGO, "worker request: "
1653 			"need cookie or stateful transport");
1654 		log_addr(VERB_ALGO, "from",&repinfo->remote_addr
1655 		                          , repinfo->remote_addrlen);
1656 		EDNS_OPT_LIST_APPEND_EDE(&edns.opt_list_out,
1657 			worker->scratchpad, LDNS_EDE_OTHER,
1658 			"DNS Cookie needed for UDP replies");
1659 		error_encode(c->buffer,
1660 			(LDNS_RCODE_REFUSED|BIT_TC), &qinfo,
1661 			*(uint16_t*)(void *)
1662 			sldns_buffer_begin(c->buffer),
1663 			sldns_buffer_read_u16_at(c->buffer, 2),
1664 			&edns);
1665 		regional_free_all(worker->scratchpad);
1666 		goto send_reply;
1667 	}
1668 
1669 	if(edns.udp_size > worker->daemon->cfg->max_udp_size &&
1670 		c->type == comm_udp) {
1671 		verbose(VERB_QUERY,
1672 			"worker request: max UDP reply size modified"
1673 			" (%d to max-udp-size)", (int)edns.udp_size);
1674 		log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1675 			repinfo->client_addrlen);
1676 		edns.udp_size = worker->daemon->cfg->max_udp_size;
1677 	}
1678 	if(edns.udp_size < LDNS_HEADER_SIZE) {
1679 		verbose(VERB_ALGO, "worker request: edns is too small.");
1680 		log_addr(VERB_CLIENT, "from", &repinfo->client_addr,
1681 			repinfo->client_addrlen);
1682 		LDNS_QR_SET(sldns_buffer_begin(c->buffer));
1683 		LDNS_TC_SET(sldns_buffer_begin(c->buffer));
1684 		LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
1685 			LDNS_RCODE_SERVFAIL);
1686 		sldns_buffer_set_position(c->buffer, LDNS_HEADER_SIZE);
1687 		sldns_buffer_write_at(c->buffer, 4,
1688 			(uint8_t*)"\0\0\0\0\0\0\0\0", 8);
1689 		sldns_buffer_flip(c->buffer);
1690 		regional_free_all(worker->scratchpad);
1691 		goto send_reply;
1692 	}
1693 	if(worker->stats.extended)
1694 		server_stats_insquery(&worker->stats, c, qinfo.qtype,
1695 			qinfo.qclass, &edns, repinfo);
1696 	if(c->type != comm_udp)
1697 		edns.udp_size = 65535; /* max size for TCP replies */
1698 	if(qinfo.qclass == LDNS_RR_CLASS_CH && answer_chaos(worker, &qinfo,
1699 		&edns, repinfo, c->buffer)) {
1700 		regional_free_all(worker->scratchpad);
1701 		goto send_reply;
1702 	}
1703 	if(LDNS_OPCODE_WIRE(sldns_buffer_begin(c->buffer)) ==
1704 		LDNS_PACKET_NOTIFY) {
1705 		answer_notify(worker, &qinfo, &edns, c->buffer,
1706 			&repinfo->client_addr, repinfo->client_addrlen);
1707 		regional_free_all(worker->scratchpad);
1708 		goto send_reply;
1709 	}
1710 	if(local_zones_answer(worker->daemon->local_zones, &worker->env, &qinfo,
1711 		&edns, c->buffer, worker->scratchpad, repinfo, acladdr->taglist,
1712 		acladdr->taglen, acladdr->tag_actions,
1713 		acladdr->tag_actions_size, acladdr->tag_datas,
1714 		acladdr->tag_datas_size, worker->daemon->cfg->tagname,
1715 		worker->daemon->cfg->num_tags, acladdr->view)) {
1716 		regional_free_all(worker->scratchpad);
1717 		if(sldns_buffer_limit(c->buffer) == 0) {
1718 			comm_point_drop_reply(repinfo);
1719 			return 0;
1720 		}
1721 		goto send_reply;
1722 	}
1723 	if(worker->env.auth_zones &&
1724 		rpz_callback_from_worker_request(worker->env.auth_zones,
1725 		&worker->env, &qinfo, &edns, c->buffer, worker->scratchpad,
1726 		repinfo, acladdr->taglist, acladdr->taglen, &worker->stats,
1727 		&rpz_passthru)) {
1728 		regional_free_all(worker->scratchpad);
1729 		if(sldns_buffer_limit(c->buffer) == 0) {
1730 			comm_point_drop_reply(repinfo);
1731 			return 0;
1732 		}
1733 		goto send_reply;
1734 	}
1735 	if(worker->env.auth_zones &&
1736 		auth_zones_answer(worker->env.auth_zones, &worker->env,
1737 		&qinfo, &edns, repinfo, c->buffer, worker->scratchpad)) {
1738 		regional_free_all(worker->scratchpad);
1739 		if(sldns_buffer_limit(c->buffer) == 0) {
1740 			comm_point_drop_reply(repinfo);
1741 			return 0;
1742 		}
1743 		/* set RA for everyone that can have recursion (based on
1744 		 * access control list) */
1745 		if(LDNS_RD_WIRE(sldns_buffer_begin(c->buffer)) &&
1746 		   acl != acl_deny_non_local && acl != acl_refuse_non_local)
1747 			LDNS_RA_SET(sldns_buffer_begin(c->buffer));
1748 		goto send_reply;
1749 	}
1750 
1751 	/* We've looked in our local zones. If the answer isn't there, we
1752 	 * might need to bail out based on ACLs now. */
1753 	if((ret=deny_refuse_non_local(c, acl, worker, repinfo, acladdr,
1754 		worker->env.cfg->ede, &check_result)) != -1)
1755 	{
1756 		regional_free_all(worker->scratchpad);
1757 		if(ret == 1)
1758 			goto send_reply;
1759 		return ret;
1760 	}
1761 
1762 	/* If this request does not have the recursion bit set, verify
1763 	 * ACLs allow the recursion bit to be treated as set. */
1764 	if(!(LDNS_RD_WIRE(sldns_buffer_begin(c->buffer))) &&
1765 		acl == acl_allow_setrd ) {
1766 		LDNS_RD_SET(sldns_buffer_begin(c->buffer));
1767 	}
1768 
1769 	/* If this request does not have the recursion bit set, verify
1770 	 * ACLs allow the snooping. */
1771 	if(!(LDNS_RD_WIRE(sldns_buffer_begin(c->buffer))) &&
1772 		acl != acl_allow_snoop ) {
1773 		if(worker->env.cfg->ede) {
1774 			EDNS_OPT_LIST_APPEND_EDE(&edns.opt_list_out,
1775 				worker->scratchpad, LDNS_EDE_NOT_AUTHORITATIVE, "");
1776 		}
1777 		error_encode(c->buffer, LDNS_RCODE_REFUSED, &qinfo,
1778 			*(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
1779 			sldns_buffer_read_u16_at(c->buffer, 2), &edns);
1780 		regional_free_all(worker->scratchpad);
1781 		log_addr(VERB_ALGO, "refused nonrec (cache snoop) query from",
1782 			&repinfo->client_addr, repinfo->client_addrlen);
1783 
1784 		goto send_reply;
1785 	}
1786 
1787 	/* If we've found a local alias, replace the qname with the alias
1788 	 * target before resolving it. */
1789 	if(qinfo.local_alias) {
1790 		struct ub_packed_rrset_key* rrset = qinfo.local_alias->rrset;
1791 		struct packed_rrset_data* d = rrset->entry.data;
1792 
1793 		/* Sanity check: our current implementation only supports
1794 		 * a single CNAME RRset as a local alias. */
1795 		if(qinfo.local_alias->next ||
1796 			rrset->rk.type != htons(LDNS_RR_TYPE_CNAME) ||
1797 			d->count != 1) {
1798 			log_err("assumption failure: unexpected local alias");
1799 			regional_free_all(worker->scratchpad);
1800 			return 0; /* drop it */
1801 		}
1802 		qinfo.qname = d->rr_data[0] + 2;
1803 		qinfo.qname_len = d->rr_len[0] - 2;
1804 	}
1805 
1806 	/* If we may apply IP-based actions to the answer, build the client
1807 	 * information.  As this can be expensive, skip it if there is
1808 	 * absolutely no possibility of it. */
1809 	if((worker->daemon->use_response_ip || worker->daemon->use_rpz) &&
1810 		(qinfo.qtype == LDNS_RR_TYPE_A ||
1811 		qinfo.qtype == LDNS_RR_TYPE_AAAA ||
1812 		qinfo.qtype == LDNS_RR_TYPE_ANY)) {
1813 		cinfo_tmp.taglist = acladdr->taglist;
1814 		cinfo_tmp.taglen = acladdr->taglen;
1815 		cinfo_tmp.tag_actions = acladdr->tag_actions;
1816 		cinfo_tmp.tag_actions_size = acladdr->tag_actions_size;
1817 		cinfo_tmp.tag_datas = acladdr->tag_datas;
1818 		cinfo_tmp.tag_datas_size = acladdr->tag_datas_size;
1819 		cinfo_tmp.view = acladdr->view;
1820 		cinfo_tmp.respip_set = worker->daemon->respip_set;
1821 		cinfo = &cinfo_tmp;
1822 	}
1823 
1824 	/* Keep the original edns list around. The pointer could change if there is
1825 	 * a cached answer (through the inplace callback function there).
1826 	 * No need to actually copy the contents as they shouldn't change.
1827 	 * Used while prefetching and subnet is enabled. */
1828 	original_edns_list = edns.opt_list_in;
1829 lookup_cache:
1830 	/* Lookup the cache.  In case we chase an intermediate CNAME chain
1831 	 * this is a two-pass operation, and lookup_qinfo is different for
1832 	 * each pass.  We should still pass the original qinfo to
1833 	 * answer_from_cache(), however, since it's used to build the reply. */
1834 	if(!edns_bypass_cache_stage(edns.opt_list_in, &worker->env)) {
1835 		is_expired_answer = 0;
1836 		is_secure_answer = 0;
1837 		h = query_info_hash(lookup_qinfo, sldns_buffer_read_u16_at(c->buffer, 2));
1838 		if((e=slabhash_lookup(worker->env.msg_cache, h, lookup_qinfo, 0))) {
1839 			struct reply_info* rep = (struct reply_info*)e->data;
1840 			/* answer from cache - we have acquired a readlock on it */
1841 			if(answer_from_cache(worker, &qinfo, cinfo, &need_drop,
1842 				&is_expired_answer, &is_secure_answer,
1843 				&alias_rrset, &partial_rep, rep,
1844 				*(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
1845 				sldns_buffer_read_u16_at(c->buffer, 2), repinfo,
1846 				&edns)) {
1847 				/* prefetch it if the prefetch TTL expired.
1848 				 * Note that if there is more than one pass
1849 				 * its qname must be that used for cache
1850 				 * lookup. */
1851 				if((worker->env.cfg->prefetch &&
1852 					*worker->env.now >= rep->prefetch_ttl) ||
1853 					(worker->env.cfg->serve_expired &&
1854 					*worker->env.now > rep->ttl)) {
1855 
1856 					time_t leeway = rep->ttl - *worker->env.now;
1857 					if(rep->ttl < *worker->env.now)
1858 						leeway = 0;
1859 					lock_rw_unlock(&e->lock);
1860 
1861 					reply_and_prefetch(worker, lookup_qinfo,
1862 						sldns_buffer_read_u16_at(c->buffer, 2),
1863 						repinfo, leeway,
1864 						(partial_rep || need_drop),
1865 						rpz_passthru,
1866 						original_edns_list);
1867 					if(!partial_rep) {
1868 						rc = 0;
1869 						regional_free_all(worker->scratchpad);
1870 						goto send_reply_rc;
1871 					}
1872 				} else if(!partial_rep) {
1873 					lock_rw_unlock(&e->lock);
1874 					regional_free_all(worker->scratchpad);
1875 					goto send_reply;
1876 				} else {
1877 					/* Note that we've already released the
1878 					 * lock if we're here after prefetch. */
1879 					lock_rw_unlock(&e->lock);
1880 				}
1881 				/* We've found a partial reply ending with an
1882 				 * alias.  Replace the lookup qinfo for the
1883 				 * alias target and lookup the cache again to
1884 				 * (possibly) complete the reply.  As we're
1885 				 * passing the "base" reply, there will be no
1886 				 * more alias chasing. */
1887 				memset(&qinfo_tmp, 0, sizeof(qinfo_tmp));
1888 				get_cname_target(alias_rrset, &qinfo_tmp.qname,
1889 					&qinfo_tmp.qname_len);
1890 				if(!qinfo_tmp.qname) {
1891 					log_err("unexpected: invalid answer alias");
1892 					regional_free_all(worker->scratchpad);
1893 					return 0; /* drop query */
1894 				}
1895 				qinfo_tmp.qtype = qinfo.qtype;
1896 				qinfo_tmp.qclass = qinfo.qclass;
1897 				lookup_qinfo = &qinfo_tmp;
1898 				goto lookup_cache;
1899 			}
1900 			verbose(VERB_ALGO, "answer from the cache failed");
1901 			lock_rw_unlock(&e->lock);
1902 		}
1903 
1904 		if(!LDNS_RD_WIRE(sldns_buffer_begin(c->buffer))) {
1905 			if(answer_norec_from_cache(worker, &qinfo,
1906 				*(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
1907 				sldns_buffer_read_u16_at(c->buffer, 2), repinfo,
1908 				&edns)) {
1909 				regional_free_all(worker->scratchpad);
1910 				goto send_reply;
1911 			}
1912 			verbose(VERB_ALGO, "answer norec from cache -- "
1913 				"need to validate or not primed");
1914 		}
1915 	}
1916 	sldns_buffer_rewind(c->buffer);
1917 	server_stats_querymiss(&worker->stats, worker);
1918 
1919 	if(verbosity >= VERB_CLIENT) {
1920 		if(c->type == comm_udp)
1921 			log_addr(VERB_CLIENT, "udp request from",
1922 				&repinfo->client_addr, repinfo->client_addrlen);
1923 		else	log_addr(VERB_CLIENT, "tcp request from",
1924 				&repinfo->client_addr, repinfo->client_addrlen);
1925 	}
1926 
1927 	/* grab a work request structure for this new request */
1928 	mesh_new_client(worker->env.mesh, &qinfo, cinfo,
1929 		sldns_buffer_read_u16_at(c->buffer, 2),
1930 		&edns, repinfo, *(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
1931 		rpz_passthru);
1932 	regional_free_all(worker->scratchpad);
1933 	worker_mem_report(worker, NULL);
1934 	return 0;
1935 
1936 send_reply:
1937 	rc = 1;
1938 send_reply_rc:
1939 	if(need_drop) {
1940 		comm_point_drop_reply(repinfo);
1941 		return 0;
1942 	}
1943 	if(is_expired_answer) {
1944 		worker->stats.ans_expired++;
1945 	}
1946 	server_stats_insrcode(&worker->stats, c->buffer);
1947 	if(worker->stats.extended) {
1948 		if(is_secure_answer) worker->stats.ans_secure++;
1949 	}
1950 #ifdef USE_DNSTAP
1951 	/*
1952 	 * sending src (client)/dst (local service) addresses over DNSTAP from send_reply code label (when we serviced local zone for ex.)
1953 	 */
1954 	if(worker->dtenv.log_client_response_messages && rc !=0) {
1955 		log_addr(VERB_ALGO, "from local addr", (void*)repinfo->c->socket->addr, repinfo->c->socket->addrlen);
1956 		log_addr(VERB_ALGO, "response to client", &repinfo->client_addr, repinfo->client_addrlen);
1957 		dt_msg_send_client_response(&worker->dtenv, &repinfo->client_addr, (void*)repinfo->c->socket->addr, c->type, c->ssl, c->buffer);
1958 	}
1959 #endif
1960 	if(worker->env.cfg->log_replies)
1961 	{
1962 		struct timeval tv;
1963 		memset(&tv, 0, sizeof(tv));
1964 		if(qinfo.local_alias && qinfo.local_alias->rrset &&
1965 			qinfo.local_alias->rrset->rk.dname) {
1966 			/* log original qname, before the local alias was
1967 			 * used to resolve that CNAME to something else */
1968 			qinfo.qname = qinfo.local_alias->rrset->rk.dname;
1969 			log_reply_info(NO_VERBOSE, &qinfo,
1970 				&repinfo->client_addr, repinfo->client_addrlen,
1971 				tv, 1, c->buffer,
1972 				(worker->env.cfg->log_destaddr?(void*)repinfo->c->socket->addr:NULL),
1973 				c->type);
1974 		} else {
1975 			log_reply_info(NO_VERBOSE, &qinfo,
1976 				&repinfo->client_addr, repinfo->client_addrlen,
1977 				tv, 1, c->buffer,
1978 				(worker->env.cfg->log_destaddr?(void*)repinfo->c->socket->addr:NULL),
1979 				c->type);
1980 		}
1981 	}
1982 #ifdef USE_DNSCRYPT
1983 	if(!dnsc_handle_uncurved_request(repinfo)) {
1984 		return 0;
1985 	}
1986 #endif
1987 	return rc;
1988 }
1989 
1990 void
1991 worker_sighandler(int sig, void* arg)
1992 {
1993 	/* note that log, print, syscalls here give race conditions.
1994 	 * And cause hangups if the log-lock is held by the application. */
1995 	struct worker* worker = (struct worker*)arg;
1996 	switch(sig) {
1997 #ifdef SIGHUP
1998 		case SIGHUP:
1999 			comm_base_exit(worker->base);
2000 			break;
2001 #endif
2002 #ifdef SIGBREAK
2003 		case SIGBREAK:
2004 #endif
2005 		case SIGINT:
2006 			worker->need_to_exit = 1;
2007 			comm_base_exit(worker->base);
2008 			break;
2009 #ifdef SIGQUIT
2010 		case SIGQUIT:
2011 			worker->need_to_exit = 1;
2012 			comm_base_exit(worker->base);
2013 			break;
2014 #endif
2015 		case SIGTERM:
2016 			worker->need_to_exit = 1;
2017 			comm_base_exit(worker->base);
2018 			break;
2019 		default:
2020 			/* unknown signal, ignored */
2021 			break;
2022 	}
2023 }
2024 
2025 /** restart statistics timer for worker, if enabled */
2026 static void
2027 worker_restart_timer(struct worker* worker)
2028 {
2029 	if(worker->env.cfg->stat_interval > 0) {
2030 		struct timeval tv;
2031 #ifndef S_SPLINT_S
2032 		tv.tv_sec = worker->env.cfg->stat_interval;
2033 		tv.tv_usec = 0;
2034 #endif
2035 		comm_timer_set(worker->stat_timer, &tv);
2036 	}
2037 }
2038 
2039 void worker_stat_timer_cb(void* arg)
2040 {
2041 	struct worker* worker = (struct worker*)arg;
2042 	server_stats_log(&worker->stats, worker, worker->thread_num);
2043 	mesh_stats(worker->env.mesh, "mesh has");
2044 	worker_mem_report(worker, NULL);
2045 	/* SHM is enabled, process data to SHM */
2046 	if (worker->daemon->cfg->shm_enable) {
2047 		shm_main_run(worker);
2048 	}
2049 	if(!worker->daemon->cfg->stat_cumulative) {
2050 		worker_stats_clear(worker);
2051 	}
2052 	/* start next timer */
2053 	worker_restart_timer(worker);
2054 }
2055 
2056 void worker_probe_timer_cb(void* arg)
2057 {
2058 	struct worker* worker = (struct worker*)arg;
2059 	struct timeval tv;
2060 #ifndef S_SPLINT_S
2061 	tv.tv_sec = (time_t)autr_probe_timer(&worker->env);
2062 	tv.tv_usec = 0;
2063 #endif
2064 	if(tv.tv_sec != 0)
2065 		comm_timer_set(worker->env.probe_timer, &tv);
2066 }
2067 
2068 struct worker*
2069 worker_create(struct daemon* daemon, int id, int* ports, int n)
2070 {
2071 	unsigned int seed;
2072 	struct worker* worker = (struct worker*)calloc(1,
2073 		sizeof(struct worker));
2074 	if(!worker)
2075 		return NULL;
2076 	worker->numports = n;
2077 	worker->ports = (int*)memdup(ports, sizeof(int)*n);
2078 	if(!worker->ports) {
2079 		free(worker);
2080 		return NULL;
2081 	}
2082 	worker->daemon = daemon;
2083 	worker->thread_num = id;
2084 	if(!(worker->cmd = tube_create())) {
2085 		free(worker->ports);
2086 		free(worker);
2087 		return NULL;
2088 	}
2089 	/* create random state here to avoid locking trouble in RAND_bytes */
2090 	if(!(worker->rndstate = ub_initstate(daemon->rand))) {
2091 		log_err("could not init random numbers.");
2092 		tube_delete(worker->cmd);
2093 		free(worker->ports);
2094 		free(worker);
2095 		return NULL;
2096 	}
2097 	explicit_bzero(&seed, sizeof(seed));
2098 	return worker;
2099 }
2100 
2101 int
2102 worker_init(struct worker* worker, struct config_file *cfg,
2103 	struct listen_port* ports, int do_sigs)
2104 {
2105 #ifdef USE_DNSTAP
2106 	struct dt_env* dtenv = &worker->dtenv;
2107 #else
2108 	void* dtenv = NULL;
2109 #endif
2110 #ifdef HAVE_GETTID
2111 	worker->thread_tid = gettid();
2112 #endif
2113 	worker->need_to_exit = 0;
2114 	worker->base = comm_base_create(do_sigs);
2115 	if(!worker->base) {
2116 		log_err("could not create event handling base");
2117 		worker_delete(worker);
2118 		return 0;
2119 	}
2120 	comm_base_set_slow_accept_handlers(worker->base, &worker_stop_accept,
2121 		&worker_start_accept, worker);
2122 	if(do_sigs) {
2123 #ifdef SIGHUP
2124 		ub_thread_sig_unblock(SIGHUP);
2125 #endif
2126 #ifdef SIGBREAK
2127 		ub_thread_sig_unblock(SIGBREAK);
2128 #endif
2129 		ub_thread_sig_unblock(SIGINT);
2130 #ifdef SIGQUIT
2131 		ub_thread_sig_unblock(SIGQUIT);
2132 #endif
2133 		ub_thread_sig_unblock(SIGTERM);
2134 #ifndef LIBEVENT_SIGNAL_PROBLEM
2135 		worker->comsig = comm_signal_create(worker->base,
2136 			worker_sighandler, worker);
2137 		if(!worker->comsig
2138 #ifdef SIGHUP
2139 			|| !comm_signal_bind(worker->comsig, SIGHUP)
2140 #endif
2141 #ifdef SIGQUIT
2142 			|| !comm_signal_bind(worker->comsig, SIGQUIT)
2143 #endif
2144 			|| !comm_signal_bind(worker->comsig, SIGTERM)
2145 #ifdef SIGBREAK
2146 			|| !comm_signal_bind(worker->comsig, SIGBREAK)
2147 #endif
2148 			|| !comm_signal_bind(worker->comsig, SIGINT)) {
2149 			log_err("could not create signal handlers");
2150 			worker_delete(worker);
2151 			return 0;
2152 		}
2153 #endif /* LIBEVENT_SIGNAL_PROBLEM */
2154 		if(!daemon_remote_open_accept(worker->daemon->rc,
2155 			worker->daemon->rc_ports, worker)) {
2156 			worker_delete(worker);
2157 			return 0;
2158 		}
2159 #ifdef UB_ON_WINDOWS
2160 		wsvc_setup_worker(worker);
2161 #endif /* UB_ON_WINDOWS */
2162 	} else { /* !do_sigs */
2163 		worker->comsig = NULL;
2164 	}
2165 #ifdef USE_DNSTAP
2166 	if(cfg->dnstap) {
2167 		log_assert(worker->daemon->dtenv != NULL);
2168 		memcpy(&worker->dtenv, worker->daemon->dtenv, sizeof(struct dt_env));
2169 		if(!dt_init(&worker->dtenv, worker->base))
2170 			fatal_exit("dt_init failed");
2171 	}
2172 #endif
2173 	worker->front = listen_create(worker->base, ports,
2174 		cfg->msg_buffer_size, (int)cfg->incoming_num_tcp,
2175 		cfg->do_tcp_keepalive
2176 			? cfg->tcp_keepalive_timeout
2177 			: cfg->tcp_idle_timeout,
2178 		cfg->harden_large_queries, cfg->http_max_streams,
2179 		cfg->http_endpoint, cfg->http_notls_downstream,
2180 		worker->daemon->tcl, worker->daemon->listen_sslctx,
2181 		dtenv, worker_handle_request, worker);
2182 	if(!worker->front) {
2183 		log_err("could not create listening sockets");
2184 		worker_delete(worker);
2185 		return 0;
2186 	}
2187 	worker->back = outside_network_create(worker->base,
2188 		cfg->msg_buffer_size, (size_t)cfg->outgoing_num_ports,
2189 		cfg->out_ifs, cfg->num_out_ifs, cfg->do_ip4, cfg->do_ip6,
2190 		cfg->do_tcp?cfg->outgoing_num_tcp:0, cfg->ip_dscp,
2191 		worker->daemon->env->infra_cache, worker->rndstate,
2192 		cfg->use_caps_bits_for_id, worker->ports, worker->numports,
2193 		cfg->unwanted_threshold, cfg->outgoing_tcp_mss,
2194 		&worker_alloc_cleanup, worker,
2195 		cfg->do_udp || cfg->udp_upstream_without_downstream,
2196 		worker->daemon->connect_sslctx, cfg->delay_close,
2197 		cfg->tls_use_sni, dtenv, cfg->udp_connect,
2198 		cfg->max_reuse_tcp_queries, cfg->tcp_reuse_timeout,
2199 		cfg->tcp_auth_query_timeout);
2200 	if(!worker->back) {
2201 		log_err("could not create outgoing sockets");
2202 		worker_delete(worker);
2203 		return 0;
2204 	}
2205 	iterator_set_ip46_support(&worker->daemon->mods, worker->daemon->env,
2206 		worker->back);
2207 	/* start listening to commands */
2208 	if(!tube_setup_bg_listen(worker->cmd, worker->base,
2209 		&worker_handle_control_cmd, worker)) {
2210 		log_err("could not create control compt.");
2211 		worker_delete(worker);
2212 		return 0;
2213 	}
2214 	worker->stat_timer = comm_timer_create(worker->base,
2215 		worker_stat_timer_cb, worker);
2216 	if(!worker->stat_timer) {
2217 		log_err("could not create statistics timer");
2218 	}
2219 
2220 	/* we use the msg_buffer_size as a good estimate for what the
2221 	 * user wants for memory usage sizes */
2222 	worker->scratchpad = regional_create_custom(cfg->msg_buffer_size);
2223 	if(!worker->scratchpad) {
2224 		log_err("malloc failure");
2225 		worker_delete(worker);
2226 		return 0;
2227 	}
2228 
2229 	server_stats_init(&worker->stats, cfg);
2230 	worker->alloc = worker->daemon->worker_allocs[worker->thread_num];
2231 	alloc_set_id_cleanup(worker->alloc, &worker_alloc_cleanup, worker);
2232 	worker->env = *worker->daemon->env;
2233 	comm_base_timept(worker->base, &worker->env.now, &worker->env.now_tv);
2234 	worker->env.worker = worker;
2235 	worker->env.worker_base = worker->base;
2236 	worker->env.send_query = &worker_send_query;
2237 	worker->env.alloc = worker->alloc;
2238 	worker->env.outnet = worker->back;
2239 	worker->env.rnd = worker->rndstate;
2240 	/* If case prefetch is triggered, the corresponding mesh will clear
2241 	 * the scratchpad for the module env in the middle of request handling.
2242 	 * It would be prone to a use-after-free kind of bug, so we avoid
2243 	 * sharing it with worker's own scratchpad at the cost of having
2244 	 * one more pad per worker. */
2245 	worker->env.scratch = regional_create_custom(cfg->msg_buffer_size);
2246 	if(!worker->env.scratch) {
2247 		log_err("malloc failure");
2248 		worker_delete(worker);
2249 		return 0;
2250 	}
2251 	worker->env.mesh = mesh_create(&worker->daemon->mods, &worker->env);
2252 	if(!worker->env.mesh) {
2253 		log_err("malloc failure");
2254 		worker_delete(worker);
2255 		return 0;
2256 	}
2257 	/* Pass on daemon variables that we would need in the mesh area */
2258 	worker->env.mesh->use_response_ip = worker->daemon->use_response_ip;
2259 	worker->env.mesh->use_rpz = worker->daemon->use_rpz;
2260 
2261 	worker->env.detach_subs = &mesh_detach_subs;
2262 	worker->env.attach_sub = &mesh_attach_sub;
2263 	worker->env.add_sub = &mesh_add_sub;
2264 	worker->env.kill_sub = &mesh_state_delete;
2265 	worker->env.detect_cycle = &mesh_detect_cycle;
2266 	worker->env.scratch_buffer = sldns_buffer_new(cfg->msg_buffer_size);
2267 	if(!worker->env.scratch_buffer) {
2268 		log_err("malloc failure");
2269 		worker_delete(worker);
2270 		return 0;
2271 	}
2272 	/* one probe timer per process -- if we have 5011 anchors */
2273 	if(autr_get_num_anchors(worker->env.anchors) > 0
2274 #ifndef THREADS_DISABLED
2275 		&& worker->thread_num == 0
2276 #endif
2277 		) {
2278 		struct timeval tv;
2279 		tv.tv_sec = 0;
2280 		tv.tv_usec = 0;
2281 		worker->env.probe_timer = comm_timer_create(worker->base,
2282 			worker_probe_timer_cb, worker);
2283 		if(!worker->env.probe_timer) {
2284 			log_err("could not create 5011-probe timer");
2285 		} else {
2286 			/* let timer fire, then it can reset itself */
2287 			comm_timer_set(worker->env.probe_timer, &tv);
2288 		}
2289 	}
2290 	/* zone transfer tasks, setup once per process, if any */
2291 	if(worker->env.auth_zones
2292 #ifndef THREADS_DISABLED
2293 		&& worker->thread_num == 0
2294 #endif
2295 		) {
2296 		auth_xfer_pickup_initial(worker->env.auth_zones, &worker->env);
2297 		auth_zones_pickup_zonemd_verify(worker->env.auth_zones,
2298 			&worker->env);
2299 	}
2300 #ifdef USE_DNSTAP
2301 	if(worker->daemon->cfg->dnstap
2302 #ifndef THREADS_DISABLED
2303 		&& worker->thread_num == 0
2304 #endif
2305 		) {
2306 		if(!dt_io_thread_start(dtenv->dtio, comm_base_internal(
2307 			worker->base), worker->daemon->num)) {
2308 			log_err("could not start dnstap io thread");
2309 			worker_delete(worker);
2310 			return 0;
2311 		}
2312 	}
2313 #endif /* USE_DNSTAP */
2314 	worker_mem_report(worker, NULL);
2315 	/* if statistics enabled start timer */
2316 	if(worker->env.cfg->stat_interval > 0) {
2317 		verbose(VERB_ALGO, "set statistics interval %d secs",
2318 			worker->env.cfg->stat_interval);
2319 		worker_restart_timer(worker);
2320 	}
2321 	pp_init(&sldns_write_uint16, &sldns_write_uint32);
2322 	return 1;
2323 }
2324 
2325 void
2326 worker_work(struct worker* worker)
2327 {
2328 	comm_base_dispatch(worker->base);
2329 }
2330 
2331 void
2332 worker_delete(struct worker* worker)
2333 {
2334 	if(!worker)
2335 		return;
2336 	if(worker->env.mesh && verbosity >= VERB_OPS) {
2337 		server_stats_log(&worker->stats, worker, worker->thread_num);
2338 		mesh_stats(worker->env.mesh, "mesh has");
2339 		worker_mem_report(worker, NULL);
2340 	}
2341 	outside_network_quit_prepare(worker->back);
2342 	mesh_delete(worker->env.mesh);
2343 	sldns_buffer_free(worker->env.scratch_buffer);
2344 	listen_delete(worker->front);
2345 	outside_network_delete(worker->back);
2346 	comm_signal_delete(worker->comsig);
2347 	tube_delete(worker->cmd);
2348 	comm_timer_delete(worker->stat_timer);
2349 	comm_timer_delete(worker->env.probe_timer);
2350 	free(worker->ports);
2351 	if(worker->thread_num == 0) {
2352 #ifdef UB_ON_WINDOWS
2353 		wsvc_desetup_worker(worker);
2354 #endif /* UB_ON_WINDOWS */
2355 	}
2356 #ifdef USE_DNSTAP
2357 	if(worker->daemon->cfg->dnstap
2358 #ifndef THREADS_DISABLED
2359 		&& worker->thread_num == 0
2360 #endif
2361 		) {
2362 		dt_io_thread_stop(worker->dtenv.dtio);
2363 	}
2364 	dt_deinit(&worker->dtenv);
2365 #endif /* USE_DNSTAP */
2366 	comm_base_delete(worker->base);
2367 	ub_randfree(worker->rndstate);
2368 	/* don't touch worker->alloc, as it's maintained in daemon */
2369 	regional_destroy(worker->env.scratch);
2370 	regional_destroy(worker->scratchpad);
2371 	free(worker);
2372 }
2373 
2374 struct outbound_entry*
2375 worker_send_query(struct query_info* qinfo, uint16_t flags, int dnssec,
2376 	int want_dnssec, int nocaps, int check_ratelimit,
2377 	struct sockaddr_storage* addr, socklen_t addrlen, uint8_t* zone,
2378 	size_t zonelen, int tcp_upstream, int ssl_upstream, char* tls_auth_name,
2379 	struct module_qstate* q, int* was_ratelimited)
2380 {
2381 	struct worker* worker = q->env->worker;
2382 	struct outbound_entry* e = (struct outbound_entry*)regional_alloc(
2383 		q->region, sizeof(*e));
2384 	if(!e)
2385 		return NULL;
2386 	e->qstate = q;
2387 	e->qsent = outnet_serviced_query(worker->back, qinfo, flags, dnssec,
2388 		want_dnssec, nocaps, check_ratelimit, tcp_upstream,
2389 		ssl_upstream, tls_auth_name, addr, addrlen, zone, zonelen, q,
2390 		worker_handle_service_reply, e, worker->back->udp_buff, q->env,
2391 		was_ratelimited);
2392 	if(!e->qsent) {
2393 		return NULL;
2394 	}
2395 	return e;
2396 }
2397 
2398 void
2399 worker_alloc_cleanup(void* arg)
2400 {
2401 	struct worker* worker = (struct worker*)arg;
2402 	slabhash_clear(&worker->env.rrset_cache->table);
2403 	slabhash_clear(worker->env.msg_cache);
2404 }
2405 
2406 void worker_stats_clear(struct worker* worker)
2407 {
2408 	server_stats_init(&worker->stats, worker->env.cfg);
2409 	mesh_stats_clear(worker->env.mesh);
2410 	worker->back->unwanted_replies = 0;
2411 	worker->back->num_tcp_outgoing = 0;
2412 	worker->back->num_udp_outgoing = 0;
2413 }
2414 
2415 void worker_start_accept(void* arg)
2416 {
2417 	struct worker* worker = (struct worker*)arg;
2418 	listen_start_accept(worker->front);
2419 	if(worker->thread_num == 0)
2420 		daemon_remote_start_accept(worker->daemon->rc);
2421 }
2422 
2423 void worker_stop_accept(void* arg)
2424 {
2425 	struct worker* worker = (struct worker*)arg;
2426 	listen_stop_accept(worker->front);
2427 	if(worker->thread_num == 0)
2428 		daemon_remote_stop_accept(worker->daemon->rc);
2429 }
2430 
2431 /* --- fake callbacks for fptr_wlist to work --- */
2432 struct outbound_entry* libworker_send_query(
2433 	struct query_info* ATTR_UNUSED(qinfo),
2434 	uint16_t ATTR_UNUSED(flags), int ATTR_UNUSED(dnssec),
2435 	int ATTR_UNUSED(want_dnssec), int ATTR_UNUSED(nocaps),
2436 	int ATTR_UNUSED(check_ratelimit),
2437 	struct sockaddr_storage* ATTR_UNUSED(addr), socklen_t ATTR_UNUSED(addrlen),
2438 	uint8_t* ATTR_UNUSED(zone), size_t ATTR_UNUSED(zonelen), int ATTR_UNUSED(tcp_upstream),
2439 	int ATTR_UNUSED(ssl_upstream), char* ATTR_UNUSED(tls_auth_name),
2440 	struct module_qstate* ATTR_UNUSED(q), int* ATTR_UNUSED(was_ratelimited))
2441 {
2442 	log_assert(0);
2443 	return 0;
2444 }
2445 
2446 int libworker_handle_service_reply(struct comm_point* ATTR_UNUSED(c),
2447 	void* ATTR_UNUSED(arg), int ATTR_UNUSED(error),
2448         struct comm_reply* ATTR_UNUSED(reply_info))
2449 {
2450 	log_assert(0);
2451 	return 0;
2452 }
2453 
2454 void libworker_handle_control_cmd(struct tube* ATTR_UNUSED(tube),
2455         uint8_t* ATTR_UNUSED(buffer), size_t ATTR_UNUSED(len),
2456         int ATTR_UNUSED(error), void* ATTR_UNUSED(arg))
2457 {
2458 	log_assert(0);
2459 }
2460 
2461 void libworker_fg_done_cb(void* ATTR_UNUSED(arg), int ATTR_UNUSED(rcode),
2462 	sldns_buffer* ATTR_UNUSED(buf), enum sec_status ATTR_UNUSED(s),
2463 	char* ATTR_UNUSED(why_bogus), int ATTR_UNUSED(was_ratelimited))
2464 {
2465 	log_assert(0);
2466 }
2467 
2468 void libworker_bg_done_cb(void* ATTR_UNUSED(arg), int ATTR_UNUSED(rcode),
2469 	sldns_buffer* ATTR_UNUSED(buf), enum sec_status ATTR_UNUSED(s),
2470 	char* ATTR_UNUSED(why_bogus), int ATTR_UNUSED(was_ratelimited))
2471 {
2472 	log_assert(0);
2473 }
2474 
2475 void libworker_event_done_cb(void* ATTR_UNUSED(arg), int ATTR_UNUSED(rcode),
2476 	sldns_buffer* ATTR_UNUSED(buf), enum sec_status ATTR_UNUSED(s),
2477 	char* ATTR_UNUSED(why_bogus), int ATTR_UNUSED(was_ratelimited))
2478 {
2479 	log_assert(0);
2480 }
2481 
2482 int context_query_cmp(const void* ATTR_UNUSED(a), const void* ATTR_UNUSED(b))
2483 {
2484 	log_assert(0);
2485 	return 0;
2486 }
2487 
2488 int order_lock_cmp(const void* ATTR_UNUSED(e1), const void* ATTR_UNUSED(e2))
2489 {
2490 	log_assert(0);
2491 	return 0;
2492 }
2493 
2494 int codeline_cmp(const void* ATTR_UNUSED(a), const void* ATTR_UNUSED(b))
2495 {
2496 	log_assert(0);
2497 	return 0;
2498 }
2499 
2500 #ifdef USE_DNSTAP
2501 void dtio_tap_callback(int ATTR_UNUSED(fd), short ATTR_UNUSED(ev),
2502 	void* ATTR_UNUSED(arg))
2503 {
2504 	log_assert(0);
2505 }
2506 #endif
2507 
2508 #ifdef USE_DNSTAP
2509 void dtio_mainfdcallback(int ATTR_UNUSED(fd), short ATTR_UNUSED(ev),
2510 	void* ATTR_UNUSED(arg))
2511 {
2512 	log_assert(0);
2513 }
2514 #endif
2515