xref: /freebsd/contrib/unbound/libunbound/libworker.c (revision 397e83df75e0fcd0d3fcb95ae4d794cb7600fc89)
1 /*
2  * libunbound/worker.c - worker thread or process that resolves
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 contains the worker process or thread that performs
40  * the DNS resolving and validation. The worker is called by a procedure
41  * and if in the background continues until exit, if in the foreground
42  * returns from the procedure when done.
43  */
44 #include "config.h"
45 #ifdef HAVE_SSL
46 #include <openssl/ssl.h>
47 #endif
48 #include "libunbound/libworker.h"
49 #include "libunbound/context.h"
50 #include "libunbound/unbound.h"
51 #include "libunbound/worker.h"
52 #include "libunbound/unbound-event.h"
53 #include "services/outside_network.h"
54 #include "services/mesh.h"
55 #include "services/localzone.h"
56 #include "services/cache/rrset.h"
57 #include "services/outbound_list.h"
58 #include "services/authzone.h"
59 #include "util/fptr_wlist.h"
60 #include "util/module.h"
61 #include "util/regional.h"
62 #include "util/random.h"
63 #include "util/config_file.h"
64 #include "util/netevent.h"
65 #include "util/proxy_protocol.h"
66 #include "util/storage/lookup3.h"
67 #include "util/storage/slabhash.h"
68 #include "util/net_help.h"
69 #include "util/data/dname.h"
70 #include "util/data/msgreply.h"
71 #include "util/data/msgencode.h"
72 #include "util/tube.h"
73 #include "sldns/sbuffer.h"
74 #include "sldns/str2wire.h"
75 #ifdef USE_DNSTAP
76 #include "dnstap/dtstream.h"
77 #endif
78 
79 #ifdef HAVE_TARGETCONDITIONALS_H
80 #include <TargetConditionals.h>
81 #endif
82 
83 #if (defined(TARGET_OS_TV) && TARGET_OS_TV) || (defined(TARGET_OS_WATCH) && TARGET_OS_WATCH)
84 #undef HAVE_FORK
85 #endif
86 
87 /** handle new query command for bg worker */
88 static void handle_newq(struct libworker* w, uint8_t* buf, uint32_t len);
89 
90 /** delete libworker env */
91 static void
92 libworker_delete_env(struct libworker* w)
93 {
94 	if(w->env) {
95 		outside_network_quit_prepare(w->back);
96 		mesh_delete(w->env->mesh);
97 		context_release_alloc(w->ctx, w->env->alloc,
98 			!w->is_bg || w->is_bg_thread);
99 		sldns_buffer_free(w->env->scratch_buffer);
100 		regional_destroy(w->env->scratch);
101 		ub_randfree(w->env->rnd);
102 		free(w->env);
103 	}
104 #ifdef HAVE_SSL
105 	SSL_CTX_free(w->sslctx);
106 #endif
107 	outside_network_delete(w->back);
108 }
109 
110 /** delete libworker struct */
111 static void
112 libworker_delete(struct libworker* w)
113 {
114 	if(!w) return;
115 	libworker_delete_env(w);
116 	comm_base_delete(w->base);
117 	free(w);
118 }
119 
120 void
121 libworker_delete_event(struct libworker* w)
122 {
123 	if(!w) return;
124 	libworker_delete_env(w);
125 	comm_base_delete_no_base(w->base);
126 	free(w);
127 }
128 
129 /** setup fresh libworker struct */
130 static struct libworker*
131 libworker_setup(struct ub_ctx* ctx, int is_bg, struct ub_event_base* eb)
132 {
133 	struct libworker* w = (struct libworker*)calloc(1, sizeof(*w));
134 	struct config_file* cfg = ctx->env->cfg;
135 	int* ports;
136 	int numports;
137 	if(!w) return NULL;
138 	w->is_bg = is_bg;
139 	w->ctx = ctx;
140 	w->env = (struct module_env*)malloc(sizeof(*w->env));
141 	if(!w->env) {
142 		free(w);
143 		return NULL;
144 	}
145 	*w->env = *ctx->env;
146 	w->env->alloc = context_obtain_alloc(ctx, !w->is_bg || w->is_bg_thread);
147 	if(!w->env->alloc) {
148 		libworker_delete(w);
149 		return NULL;
150 	}
151 	w->thread_num = w->env->alloc->thread_num;
152 	alloc_set_id_cleanup(w->env->alloc, &libworker_alloc_cleanup, w);
153 	if(!w->is_bg || w->is_bg_thread) {
154 		lock_basic_lock(&ctx->cfglock);
155 	}
156 	w->env->scratch = regional_create_custom(cfg->msg_buffer_size);
157 	w->env->scratch_buffer = sldns_buffer_new(cfg->msg_buffer_size);
158 #ifdef HAVE_SSL
159 	w->sslctx = connect_sslctx_create(NULL, NULL,
160 		cfg->tls_cert_bundle, cfg->tls_win_cert);
161 	if(!w->sslctx) {
162 		/* to make the setup fail after unlock */
163 		sldns_buffer_free(w->env->scratch_buffer);
164 		w->env->scratch_buffer = NULL;
165 	}
166 #endif
167 	if(!w->is_bg || w->is_bg_thread) {
168 		lock_basic_unlock(&ctx->cfglock);
169 	}
170 	if(!w->env->scratch || !w->env->scratch_buffer) {
171 		libworker_delete(w);
172 		return NULL;
173 	}
174 	w->env->worker = (struct worker*)w;
175 	w->env->probe_timer = NULL;
176 	if(!w->is_bg || w->is_bg_thread) {
177 		lock_basic_lock(&ctx->cfglock);
178 	}
179 	if(!(w->env->rnd = ub_initstate(ctx->seed_rnd))) {
180 		if(!w->is_bg || w->is_bg_thread) {
181 			lock_basic_unlock(&ctx->cfglock);
182 		}
183 		libworker_delete(w);
184 		return NULL;
185 	}
186 	if(!w->is_bg || w->is_bg_thread) {
187 		lock_basic_unlock(&ctx->cfglock);
188 	}
189 	if(1) {
190 		/* primitive lockout for threading: if it overwrites another
191 		 * thread it is like wiping the cache (which is likely empty
192 		 * at the start) */
193 		/* note we are holding the ctx lock in normal threaded
194 		 * cases so that is solved properly, it is only for many ctx
195 		 * in different threads that this may clash */
196 		static int done_raninit = 0;
197 		if(!done_raninit) {
198 			done_raninit = 1;
199 			hash_set_raninit((uint32_t)ub_random(w->env->rnd));
200 		}
201 	}
202 
203 	if(eb)
204 		w->base = comm_base_create_event(eb);
205 	else	w->base = comm_base_create(0);
206 	if(!w->base) {
207 		libworker_delete(w);
208 		return NULL;
209 	}
210 	w->env->worker_base = w->base;
211 	if(!w->is_bg || w->is_bg_thread) {
212 		lock_basic_lock(&ctx->cfglock);
213 	}
214 	numports = cfg_condense_ports(cfg, &ports);
215 	if(numports == 0) {
216 		if(!w->is_bg || w->is_bg_thread) {
217 			lock_basic_unlock(&ctx->cfglock);
218 		}
219 		libworker_delete(w);
220 		return NULL;
221 	}
222 	w->back = outside_network_create(w->base, cfg->msg_buffer_size,
223 		(size_t)cfg->outgoing_num_ports, cfg->out_ifs,
224 		cfg->num_out_ifs, cfg->do_ip4, cfg->do_ip6,
225 		cfg->do_tcp?cfg->outgoing_num_tcp:0, cfg->ip_dscp,
226 		w->env->infra_cache, w->env->rnd, cfg->use_caps_bits_for_id,
227 		ports, numports, cfg->unwanted_threshold,
228 		cfg->outgoing_tcp_mss, &libworker_alloc_cleanup, w,
229 		cfg->do_udp || cfg->udp_upstream_without_downstream, w->sslctx,
230 		cfg->delay_close, cfg->tls_use_sni, NULL, cfg->udp_connect,
231 		cfg->max_reuse_tcp_queries, cfg->tcp_reuse_timeout,
232 		cfg->tcp_auth_query_timeout);
233 	w->env->outnet = w->back;
234 	if(!w->is_bg || w->is_bg_thread) {
235 		lock_basic_unlock(&ctx->cfglock);
236 	}
237 	free(ports);
238 	if(!w->back) {
239 		libworker_delete(w);
240 		return NULL;
241 	}
242 	w->env->mesh = mesh_create(&ctx->mods, w->env);
243 	if(!w->env->mesh) {
244 		libworker_delete(w);
245 		return NULL;
246 	}
247 	w->env->send_query = &libworker_send_query;
248 	w->env->detach_subs = &mesh_detach_subs;
249 	w->env->attach_sub = &mesh_attach_sub;
250 	w->env->add_sub = &mesh_add_sub;
251 	w->env->kill_sub = &mesh_state_delete;
252 	w->env->detect_cycle = &mesh_detect_cycle;
253 	comm_base_timept(w->base, &w->env->now, &w->env->now_tv);
254 	pp_init(&sldns_write_uint16, &sldns_write_uint32);
255 	return w;
256 }
257 
258 struct libworker* libworker_create_event(struct ub_ctx* ctx,
259 	struct ub_event_base* eb)
260 {
261 	return libworker_setup(ctx, 0, eb);
262 }
263 
264 /** handle cancel command for bg worker */
265 static void
266 handle_cancel(struct libworker* w, uint8_t* buf, uint32_t len)
267 {
268 	struct ctx_query* q;
269 	if(w->is_bg_thread) {
270 		lock_basic_lock(&w->ctx->cfglock);
271 		q = context_deserialize_cancel(w->ctx, buf, len);
272 		lock_basic_unlock(&w->ctx->cfglock);
273 	} else {
274 		q = context_deserialize_cancel(w->ctx, buf, len);
275 	}
276 	if(!q) {
277 		/* probably simply lookup failed, i.e. the message had been
278 		 * processed and answered before the cancel arrived */
279 		return;
280 	}
281 	q->cancelled = 1;
282 	free(buf);
283 }
284 
285 /** do control command coming into bg server */
286 static void
287 libworker_do_cmd(struct libworker* w, uint8_t* msg, uint32_t len)
288 {
289 	switch(context_serial_getcmd(msg, len)) {
290 		default:
291 		case UB_LIBCMD_ANSWER:
292 			log_err("unknown command for bg worker %d",
293 				(int)context_serial_getcmd(msg, len));
294 			/* and fall through to quit */
295 			/* fallthrough */
296 		case UB_LIBCMD_QUIT:
297 			free(msg);
298 			comm_base_exit(w->base);
299 			break;
300 		case UB_LIBCMD_NEWQUERY:
301 			handle_newq(w, msg, len);
302 			break;
303 		case UB_LIBCMD_CANCEL:
304 			handle_cancel(w, msg, len);
305 			break;
306 	}
307 }
308 
309 /** handle control command coming into server */
310 void
311 libworker_handle_control_cmd(struct tube* ATTR_UNUSED(tube),
312 	uint8_t* msg, size_t len, int err, void* arg)
313 {
314 	struct libworker* w = (struct libworker*)arg;
315 
316 	if(err != 0) {
317 		free(msg);
318 		/* it is of no use to go on, exit */
319 		comm_base_exit(w->base);
320 		return;
321 	}
322 	libworker_do_cmd(w, msg, len); /* also frees the buf */
323 }
324 
325 /** the background thread func */
326 static void*
327 libworker_dobg(void* arg)
328 {
329 	/* setup */
330 	uint32_t m;
331 	struct libworker* w = (struct libworker*)arg;
332 	struct ub_ctx* ctx;
333 	if(!w) {
334 		log_err("libunbound bg worker init failed, nomem");
335 		return NULL;
336 	}
337 	ctx = w->ctx;
338 	log_thread_set(&w->thread_num);
339 #ifdef THREADS_DISABLED
340 	/* we are forked */
341 	w->is_bg_thread = 0;
342 	/* close non-used parts of the pipes */
343 	tube_close_write(ctx->qq_pipe);
344 	tube_close_read(ctx->rr_pipe);
345 #endif
346 	if(!tube_setup_bg_listen(ctx->qq_pipe, w->base,
347 		libworker_handle_control_cmd, w)) {
348 		log_err("libunbound bg worker init failed, no bglisten");
349 		return NULL;
350 	}
351 	if(!tube_setup_bg_write(ctx->rr_pipe, w->base)) {
352 		log_err("libunbound bg worker init failed, no bgwrite");
353 		return NULL;
354 	}
355 
356 	/* do the work */
357 	comm_base_dispatch(w->base);
358 
359 	/* cleanup */
360 	m = UB_LIBCMD_QUIT;
361 	w->want_quit = 1;
362 	tube_remove_bg_listen(w->ctx->qq_pipe);
363 	tube_remove_bg_write(w->ctx->rr_pipe);
364 	libworker_delete(w);
365 	(void)tube_write_msg(ctx->rr_pipe, (uint8_t*)&m,
366 		(uint32_t)sizeof(m), 0);
367 #ifdef THREADS_DISABLED
368 	/* close pipes from forked process before exit */
369 	tube_close_read(ctx->qq_pipe);
370 	tube_close_write(ctx->rr_pipe);
371 #endif
372 	return NULL;
373 }
374 
375 int libworker_bg(struct ub_ctx* ctx)
376 {
377 	struct libworker* w;
378 	/* fork or threadcreate */
379 	lock_basic_lock(&ctx->cfglock);
380 	if(ctx->dothread) {
381 		lock_basic_unlock(&ctx->cfglock);
382 		w = libworker_setup(ctx, 1, NULL);
383 		if(!w) return UB_NOMEM;
384 		w->is_bg_thread = 1;
385 		ctx->thread_worker = w;
386 #ifdef ENABLE_LOCK_CHECKS
387 		w->thread_num = 1; /* for nicer DEBUG checklocks */
388 #endif
389 		ub_thread_create(&ctx->bg_tid, libworker_dobg, w);
390 	} else {
391 		lock_basic_unlock(&ctx->cfglock);
392 #ifndef HAVE_FORK
393 		/* no fork on windows */
394 		return UB_FORKFAIL;
395 #else /* HAVE_FORK */
396 		switch((ctx->bg_pid=fork())) {
397 			case 0:
398 				w = libworker_setup(ctx, 1, NULL);
399 				if(!w) fatal_exit("out of memory");
400 				/* close non-used parts of the pipes */
401 				tube_close_write(ctx->qq_pipe);
402 				tube_close_read(ctx->rr_pipe);
403 				(void)libworker_dobg(w);
404 				exit(0);
405 				break;
406 			case -1:
407 				return UB_FORKFAIL;
408 			default:
409 				/* close non-used parts, so that the worker
410 				 * bgprocess gets 'pipe closed' when the
411 				 * main process exits */
412 				tube_close_read(ctx->qq_pipe);
413 				tube_close_write(ctx->rr_pipe);
414 				break;
415 		}
416 #endif /* HAVE_FORK */
417 	}
418 	return UB_NOERROR;
419 }
420 
421 /** insert canonname */
422 static int
423 fill_canon(struct ub_result* res, uint8_t* s)
424 {
425 	char buf[255+2];
426 	dname_str(s, buf);
427 	res->canonname = strdup(buf);
428 	return res->canonname != 0;
429 }
430 
431 /** fill data into result */
432 static int
433 fill_res(struct ub_result* res, struct ub_packed_rrset_key* answer,
434 	uint8_t* finalcname, struct query_info* rq, struct reply_info* rep)
435 {
436 	size_t i;
437 	struct packed_rrset_data* data;
438 	res->ttl = 0;
439 	if(!answer) {
440 		if(finalcname) {
441 			if(!fill_canon(res, finalcname))
442 				return 0; /* out of memory */
443 		}
444 		if(rep->rrset_count != 0)
445 			res->ttl = (int)rep->ttl;
446 		res->data = (char**)calloc(1, sizeof(char*));
447 		if(!res->data)
448 			return 0; /* out of memory */
449 		res->len = (int*)calloc(1, sizeof(int));
450 		if(!res->len) {
451 			free(res->data);
452 			res->data = NULL;
453 			return 0; /* out of memory */
454 		}
455 		return 1;
456 	}
457 	data = (struct packed_rrset_data*)answer->entry.data;
458 	if(query_dname_compare(rq->qname, answer->rk.dname) != 0) {
459 		if(!fill_canon(res, answer->rk.dname))
460 			return 0; /* out of memory */
461 	} else	res->canonname = NULL;
462 	res->data = (char**)calloc(data->count+1, sizeof(char*));
463 	if(!res->data)
464 		return 0; /* out of memory */
465 	res->len = (int*)calloc(data->count+1, sizeof(int));
466 	if(!res->len) {
467 		free(res->data);
468 		res->data = NULL;
469 		return 0; /* out of memory */
470 	}
471 	for(i=0; i<data->count; i++) {
472 		/* remove rdlength from rdata */
473 		res->len[i] = (int)(data->rr_len[i] - 2);
474 		res->data[i] = memdup(data->rr_data[i]+2, (size_t)res->len[i]);
475 		if(!res->data[i]) {
476 			size_t j;
477 			for(j=0; j<i; j++) {
478 				free(res->data[j]);
479 				res->data[j] = NULL;
480 			}
481 			free(res->data);
482 			res->data = NULL;
483 			free(res->len);
484 			res->len = NULL;
485 			return 0; /* out of memory */
486 		}
487 	}
488 	/* ttl for positive answers, from CNAME and answer RRs */
489 	if(data->count != 0) {
490 		size_t j;
491 		res->ttl = (int)data->ttl;
492 		for(j=0; j<rep->an_numrrsets; j++) {
493 			struct packed_rrset_data* d =
494 				(struct packed_rrset_data*)rep->rrsets[j]->
495 				entry.data;
496 			if((int)d->ttl < res->ttl)
497 				res->ttl = (int)d->ttl;
498 		}
499 	}
500 	/* ttl for negative answers */
501 	if(data->count == 0 && rep->rrset_count != 0)
502 		res->ttl = (int)rep->ttl;
503 	res->data[data->count] = NULL;
504 	res->len[data->count] = 0;
505 	return 1;
506 }
507 
508 /** fill result from parsed message, on error fills servfail */
509 void
510 libworker_enter_result(struct ub_result* res, sldns_buffer* buf,
511 	struct regional* temp, enum sec_status msg_security)
512 {
513 	struct query_info rq;
514 	struct reply_info* rep;
515 	res->rcode = LDNS_RCODE_SERVFAIL;
516 	rep = parse_reply_in_temp_region(buf, temp, &rq);
517 	if(!rep) {
518 		log_err("cannot parse buf");
519 		return; /* error parsing buf, or out of memory */
520 	}
521 	if(!fill_res(res, reply_find_answer_rrset(&rq, rep),
522 		reply_find_final_cname_target(&rq, rep), &rq, rep))
523 		return; /* out of memory */
524 	/* rcode, havedata, nxdomain, secure, bogus */
525 	res->rcode = (int)FLAGS_GET_RCODE(rep->flags);
526 	if(res->data && res->data[0])
527 		res->havedata = 1;
528 	if(res->rcode == LDNS_RCODE_NXDOMAIN)
529 		res->nxdomain = 1;
530 	if(msg_security == sec_status_secure)
531 		res->secure = 1;
532 	if(msg_security == sec_status_bogus ||
533 		msg_security == sec_status_secure_sentinel_fail)
534 		res->bogus = 1;
535 }
536 
537 /** fillup fg results */
538 static void
539 libworker_fillup_fg(struct ctx_query* q, int rcode, sldns_buffer* buf,
540 	enum sec_status s, char* why_bogus, int was_ratelimited)
541 {
542 	q->res->was_ratelimited = was_ratelimited;
543 	if(why_bogus)
544 		q->res->why_bogus = strdup(why_bogus);
545 	if(rcode != 0) {
546 		q->res->rcode = rcode;
547 		q->msg_security = s;
548 		return;
549 	}
550 
551 	q->res->rcode = LDNS_RCODE_SERVFAIL;
552 	q->msg_security = sec_status_unchecked;
553 	q->msg = memdup(sldns_buffer_begin(buf), sldns_buffer_limit(buf));
554 	q->msg_len = sldns_buffer_limit(buf);
555 	if(!q->msg) {
556 		return; /* the error is in the rcode */
557 	}
558 
559 	/* canonname and results */
560 	q->msg_security = s;
561 	libworker_enter_result(q->res, buf, q->w->env->scratch, s);
562 }
563 
564 void
565 libworker_fg_done_cb(void* arg, int rcode, sldns_buffer* buf, enum sec_status s,
566 	char* why_bogus, int was_ratelimited)
567 {
568 	struct ctx_query* q = (struct ctx_query*)arg;
569 	/* fg query is done; exit comm base */
570 	comm_base_exit(q->w->base);
571 
572 	libworker_fillup_fg(q, rcode, buf, s, why_bogus, was_ratelimited);
573 }
574 
575 /** setup qinfo and edns */
576 static int
577 setup_qinfo_edns(struct libworker* w, struct ctx_query* q,
578 	struct query_info* qinfo, struct edns_data* edns)
579 {
580 	qinfo->qtype = (uint16_t)q->res->qtype;
581 	qinfo->qclass = (uint16_t)q->res->qclass;
582 	qinfo->local_alias = NULL;
583 	qinfo->qname = sldns_str2wire_dname(q->res->qname, &qinfo->qname_len);
584 	if(!qinfo->qname) {
585 		return 0;
586 	}
587 	edns->edns_present = 1;
588 	edns->ext_rcode = 0;
589 	edns->edns_version = 0;
590 	edns->bits = EDNS_DO;
591 	edns->opt_list_in = NULL;
592 	edns->opt_list_out = NULL;
593 	edns->opt_list_inplace_cb_out = NULL;
594 	edns->padding_block_size = 0;
595 	edns->cookie_present = 0;
596 	edns->cookie_valid = 0;
597 	if(sldns_buffer_capacity(w->back->udp_buff) < 65535)
598 		edns->udp_size = (uint16_t)sldns_buffer_capacity(
599 			w->back->udp_buff);
600 	else	edns->udp_size = 65535;
601 	return 1;
602 }
603 
604 int libworker_fg(struct ub_ctx* ctx, struct ctx_query* q)
605 {
606 	struct libworker* w = libworker_setup(ctx, 0, NULL);
607 	uint16_t qflags, qid;
608 	struct query_info qinfo;
609 	struct edns_data edns;
610 	if(!w)
611 		return UB_INITFAIL;
612 	if(!setup_qinfo_edns(w, q, &qinfo, &edns)) {
613 		libworker_delete(w);
614 		return UB_SYNTAX;
615 	}
616 	qid = 0;
617 	qflags = BIT_RD;
618 	q->w = w;
619 	/* see if there is a fixed answer */
620 	sldns_buffer_write_u16_at(w->back->udp_buff, 0, qid);
621 	sldns_buffer_write_u16_at(w->back->udp_buff, 2, qflags);
622 	if(local_zones_answer(ctx->local_zones, w->env, &qinfo, &edns,
623 		w->back->udp_buff, w->env->scratch, NULL, NULL, 0, NULL, 0,
624 		NULL, 0, NULL, 0, NULL)) {
625 		regional_free_all(w->env->scratch);
626 		libworker_fillup_fg(q, LDNS_RCODE_NOERROR,
627 			w->back->udp_buff, sec_status_insecure, NULL, 0);
628 		libworker_delete(w);
629 		free(qinfo.qname);
630 		return UB_NOERROR;
631 	}
632 	if(ctx->env->auth_zones && auth_zones_answer(ctx->env->auth_zones,
633 		w->env, &qinfo, &edns, NULL, w->back->udp_buff, w->env->scratch)) {
634 		regional_free_all(w->env->scratch);
635 		libworker_fillup_fg(q, LDNS_RCODE_NOERROR,
636 			w->back->udp_buff, sec_status_insecure, NULL, 0);
637 		libworker_delete(w);
638 		free(qinfo.qname);
639 		return UB_NOERROR;
640 	}
641 	/* process new query */
642 	if(!mesh_new_callback(w->env->mesh, &qinfo, qflags, &edns,
643 		w->back->udp_buff, qid, libworker_fg_done_cb, q, 0)) {
644 		free(qinfo.qname);
645 		return UB_NOMEM;
646 	}
647 	free(qinfo.qname);
648 
649 	/* wait for reply */
650 	comm_base_dispatch(w->base);
651 
652 	libworker_delete(w);
653 	return UB_NOERROR;
654 }
655 
656 void
657 libworker_event_done_cb(void* arg, int rcode, sldns_buffer* buf,
658 	enum sec_status s, char* why_bogus, int was_ratelimited)
659 {
660 	struct ctx_query* q = (struct ctx_query*)arg;
661 	ub_event_callback_type cb = q->cb_event;
662 	void* cb_arg = q->cb_arg;
663 	int cancelled = q->cancelled;
664 
665 	/* delete it now */
666 	struct ub_ctx* ctx = q->w->ctx;
667 	lock_basic_lock(&ctx->cfglock);
668 	(void)rbtree_delete(&ctx->queries, q->node.key);
669 	ctx->num_async--;
670 	context_query_delete(q);
671 	lock_basic_unlock(&ctx->cfglock);
672 
673 	if(!cancelled) {
674 		/* call callback */
675 		int sec = 0;
676 		if(s == sec_status_bogus)
677 			sec = 1;
678 		else if(s == sec_status_secure)
679 			sec = 2;
680 		(*cb)(cb_arg, rcode, (buf?(void*)sldns_buffer_begin(buf):NULL),
681 			(buf?(int)sldns_buffer_limit(buf):0), sec, why_bogus, was_ratelimited);
682 	}
683 }
684 
685 int libworker_attach_mesh(struct ub_ctx* ctx, struct ctx_query* q,
686 	int* async_id)
687 {
688 	struct libworker* w = ctx->event_worker;
689 	uint16_t qflags, qid;
690 	struct query_info qinfo;
691 	struct edns_data edns;
692 	if(!w)
693 		return UB_INITFAIL;
694 	if(!setup_qinfo_edns(w, q, &qinfo, &edns))
695 		return UB_SYNTAX;
696 	qid = 0;
697 	qflags = BIT_RD;
698 	q->w = w;
699 	/* see if there is a fixed answer */
700 	sldns_buffer_write_u16_at(w->back->udp_buff, 0, qid);
701 	sldns_buffer_write_u16_at(w->back->udp_buff, 2, qflags);
702 	if(local_zones_answer(ctx->local_zones, w->env, &qinfo, &edns,
703 		w->back->udp_buff, w->env->scratch, NULL, NULL, 0, NULL, 0,
704 		NULL, 0, NULL, 0, NULL)) {
705 		regional_free_all(w->env->scratch);
706 		free(qinfo.qname);
707 		libworker_event_done_cb(q, LDNS_RCODE_NOERROR,
708 			w->back->udp_buff, sec_status_insecure, NULL, 0);
709 		return UB_NOERROR;
710 	}
711 	if(ctx->env->auth_zones && auth_zones_answer(ctx->env->auth_zones,
712 		w->env, &qinfo, &edns, NULL, w->back->udp_buff, w->env->scratch)) {
713 		regional_free_all(w->env->scratch);
714 		free(qinfo.qname);
715 		libworker_event_done_cb(q, LDNS_RCODE_NOERROR,
716 			w->back->udp_buff, sec_status_insecure, NULL, 0);
717 		return UB_NOERROR;
718 	}
719 	/* process new query */
720 	if(async_id)
721 		*async_id = q->querynum;
722 	if(!mesh_new_callback(w->env->mesh, &qinfo, qflags, &edns,
723 		w->back->udp_buff, qid, libworker_event_done_cb, q, 0)) {
724 		free(qinfo.qname);
725 		return UB_NOMEM;
726 	}
727 	free(qinfo.qname);
728 	return UB_NOERROR;
729 }
730 
731 /** add result to the bg worker result queue */
732 static void
733 add_bg_result(struct libworker* w, struct ctx_query* q, sldns_buffer* pkt,
734 	int err, char* reason, int was_ratelimited)
735 {
736 	uint8_t* msg = NULL;
737 	uint32_t len = 0;
738 
739 	if(w->want_quit) {
740 		context_query_delete(q);
741 		return;
742 	}
743 	/* serialize and delete unneeded q */
744 	if(w->is_bg_thread) {
745 		lock_basic_lock(&w->ctx->cfglock);
746 		if(reason)
747 			q->res->why_bogus = strdup(reason);
748 		q->res->was_ratelimited = was_ratelimited;
749 		if(pkt) {
750 			q->msg_len = sldns_buffer_remaining(pkt);
751 			q->msg = memdup(sldns_buffer_begin(pkt), q->msg_len);
752 			if(!q->msg) {
753 				msg = context_serialize_answer(q, UB_NOMEM, NULL, &len);
754 			} else {
755 				msg = context_serialize_answer(q, err, NULL, &len);
756 			}
757 		} else {
758 			msg = context_serialize_answer(q, err, NULL, &len);
759 		}
760 		lock_basic_unlock(&w->ctx->cfglock);
761 	} else {
762 		if(reason)
763 			q->res->why_bogus = strdup(reason);
764 		q->res->was_ratelimited = was_ratelimited;
765 		msg = context_serialize_answer(q, err, pkt, &len);
766 		(void)rbtree_delete(&w->ctx->queries, q->node.key);
767 		w->ctx->num_async--;
768 		context_query_delete(q);
769 	}
770 
771 	if(!msg) {
772 		log_err("out of memory for async answer");
773 		return;
774 	}
775 	if(!tube_queue_item(w->ctx->rr_pipe, msg, len)) {
776 		log_err("out of memory for async answer");
777 		return;
778 	}
779 }
780 
781 void
782 libworker_bg_done_cb(void* arg, int rcode, sldns_buffer* buf, enum sec_status s,
783 	char* why_bogus, int was_ratelimited)
784 {
785 	struct ctx_query* q = (struct ctx_query*)arg;
786 
787 	if(q->cancelled || q->w->back->want_to_quit) {
788 		if(q->w->is_bg_thread) {
789 			/* delete it now */
790 			struct ub_ctx* ctx = q->w->ctx;
791 			lock_basic_lock(&ctx->cfglock);
792 			(void)rbtree_delete(&ctx->queries, q->node.key);
793 			ctx->num_async--;
794 			context_query_delete(q);
795 			lock_basic_unlock(&ctx->cfglock);
796 		}
797 		/* cancelled, do not give answer */
798 		return;
799 	}
800 	q->msg_security = s;
801 	if(!buf) {
802 		buf = q->w->env->scratch_buffer;
803 	}
804 	if(rcode != 0) {
805 		error_encode(buf, rcode, NULL, 0, BIT_RD, NULL);
806 	}
807 	add_bg_result(q->w, q, buf, UB_NOERROR, why_bogus, was_ratelimited);
808 }
809 
810 
811 /** handle new query command for bg worker */
812 static void
813 handle_newq(struct libworker* w, uint8_t* buf, uint32_t len)
814 {
815 	uint16_t qflags, qid;
816 	struct query_info qinfo;
817 	struct edns_data edns;
818 	struct ctx_query* q;
819 	if(w->is_bg_thread) {
820 		lock_basic_lock(&w->ctx->cfglock);
821 		q = context_lookup_new_query(w->ctx, buf, len);
822 		lock_basic_unlock(&w->ctx->cfglock);
823 	} else {
824 		q = context_deserialize_new_query(w->ctx, buf, len);
825 	}
826 	free(buf);
827 	if(!q) {
828 		log_err("failed to deserialize newq");
829 		return;
830 	}
831 	if(!setup_qinfo_edns(w, q, &qinfo, &edns)) {
832 		add_bg_result(w, q, NULL, UB_SYNTAX, NULL, 0);
833 		return;
834 	}
835 	qid = 0;
836 	qflags = BIT_RD;
837 	/* see if there is a fixed answer */
838 	sldns_buffer_write_u16_at(w->back->udp_buff, 0, qid);
839 	sldns_buffer_write_u16_at(w->back->udp_buff, 2, qflags);
840 	if(local_zones_answer(w->ctx->local_zones, w->env, &qinfo, &edns,
841 		w->back->udp_buff, w->env->scratch, NULL, NULL, 0, NULL, 0,
842 		NULL, 0, NULL, 0, NULL)) {
843 		regional_free_all(w->env->scratch);
844 		q->msg_security = sec_status_insecure;
845 		add_bg_result(w, q, w->back->udp_buff, UB_NOERROR, NULL, 0);
846 		free(qinfo.qname);
847 		return;
848 	}
849 	if(w->ctx->env->auth_zones && auth_zones_answer(w->ctx->env->auth_zones,
850 		w->env, &qinfo, &edns, NULL, w->back->udp_buff, w->env->scratch)) {
851 		regional_free_all(w->env->scratch);
852 		q->msg_security = sec_status_insecure;
853 		add_bg_result(w, q, w->back->udp_buff, UB_NOERROR, NULL, 0);
854 		free(qinfo.qname);
855 		return;
856 	}
857 	q->w = w;
858 	/* process new query */
859 	if(!mesh_new_callback(w->env->mesh, &qinfo, qflags, &edns,
860 		w->back->udp_buff, qid, libworker_bg_done_cb, q, 0)) {
861 		add_bg_result(w, q, NULL, UB_NOMEM, NULL, 0);
862 	}
863 	free(qinfo.qname);
864 }
865 
866 void libworker_alloc_cleanup(void* arg)
867 {
868 	struct libworker* w = (struct libworker*)arg;
869 	slabhash_clear(&w->env->rrset_cache->table);
870         slabhash_clear(w->env->msg_cache);
871 }
872 
873 struct outbound_entry* libworker_send_query(struct query_info* qinfo,
874 	uint16_t flags, int dnssec, int want_dnssec, int nocaps,
875 	int check_ratelimit,
876 	struct sockaddr_storage* addr, socklen_t addrlen, uint8_t* zone,
877 	size_t zonelen, int tcp_upstream, int ssl_upstream, char* tls_auth_name,
878 	struct module_qstate* q, int* was_ratelimited)
879 {
880 	struct libworker* w = (struct libworker*)q->env->worker;
881 	struct outbound_entry* e = (struct outbound_entry*)regional_alloc(
882 		q->region, sizeof(*e));
883 	if(!e)
884 		return NULL;
885 	e->qstate = q;
886 	e->qsent = outnet_serviced_query(w->back, qinfo, flags, dnssec,
887 		want_dnssec, nocaps, check_ratelimit, tcp_upstream, ssl_upstream,
888 		tls_auth_name, addr, addrlen, zone, zonelen, q,
889 		libworker_handle_service_reply, e, w->back->udp_buff, q->env,
890 		was_ratelimited);
891 	if(!e->qsent) {
892 		return NULL;
893 	}
894 	return e;
895 }
896 
897 int
898 libworker_handle_service_reply(struct comm_point* c, void* arg, int error,
899         struct comm_reply* reply_info)
900 {
901 	struct outbound_entry* e = (struct outbound_entry*)arg;
902 	struct libworker* lw = (struct libworker*)e->qstate->env->worker;
903 
904 	if(error != 0) {
905 		mesh_report_reply(lw->env->mesh, e, reply_info, error);
906 		return 0;
907 	}
908 	/* sanity check. */
909 	if(!LDNS_QR_WIRE(sldns_buffer_begin(c->buffer))
910 		|| LDNS_OPCODE_WIRE(sldns_buffer_begin(c->buffer)) !=
911 			LDNS_PACKET_QUERY
912 		|| LDNS_QDCOUNT(sldns_buffer_begin(c->buffer)) > 1) {
913 		/* error becomes timeout for the module as if this reply
914 		 * never arrived. */
915 		mesh_report_reply(lw->env->mesh, e, reply_info,
916 			NETEVENT_TIMEOUT);
917 		return 0;
918 	}
919 	mesh_report_reply(lw->env->mesh,  e, reply_info, NETEVENT_NOERROR);
920 	return 0;
921 }
922 
923 /* --- fake callbacks for fptr_wlist to work --- */
924 void worker_handle_control_cmd(struct tube* ATTR_UNUSED(tube),
925 	uint8_t* ATTR_UNUSED(buffer), size_t ATTR_UNUSED(len),
926 	int ATTR_UNUSED(error), void* ATTR_UNUSED(arg))
927 {
928 	log_assert(0);
929 }
930 
931 int worker_handle_request(struct comm_point* ATTR_UNUSED(c),
932 	void* ATTR_UNUSED(arg), int ATTR_UNUSED(error),
933         struct comm_reply* ATTR_UNUSED(repinfo))
934 {
935 	log_assert(0);
936 	return 0;
937 }
938 
939 int worker_handle_service_reply(struct comm_point* ATTR_UNUSED(c),
940 	void* ATTR_UNUSED(arg), int ATTR_UNUSED(error),
941         struct comm_reply* ATTR_UNUSED(reply_info))
942 {
943 	log_assert(0);
944 	return 0;
945 }
946 
947 int remote_accept_callback(struct comm_point* ATTR_UNUSED(c),
948 	void* ATTR_UNUSED(arg), int ATTR_UNUSED(error),
949         struct comm_reply* ATTR_UNUSED(repinfo))
950 {
951 	log_assert(0);
952 	return 0;
953 }
954 
955 int remote_control_callback(struct comm_point* ATTR_UNUSED(c),
956 	void* ATTR_UNUSED(arg), int ATTR_UNUSED(error),
957         struct comm_reply* ATTR_UNUSED(repinfo))
958 {
959 	log_assert(0);
960 	return 0;
961 }
962 
963 void worker_sighandler(int ATTR_UNUSED(sig), void* ATTR_UNUSED(arg))
964 {
965 	log_assert(0);
966 }
967 
968 struct outbound_entry* worker_send_query(struct query_info* ATTR_UNUSED(qinfo),
969 	uint16_t ATTR_UNUSED(flags), int ATTR_UNUSED(dnssec),
970 	int ATTR_UNUSED(want_dnssec), int ATTR_UNUSED(nocaps),
971 	int ATTR_UNUSED(check_ratelimit),
972 	struct sockaddr_storage* ATTR_UNUSED(addr), socklen_t ATTR_UNUSED(addrlen),
973 	uint8_t* ATTR_UNUSED(zone), size_t ATTR_UNUSED(zonelen), int ATTR_UNUSED(tcp_upstream),
974 	int ATTR_UNUSED(ssl_upstream), char* ATTR_UNUSED(tls_auth_name),
975 	struct module_qstate* ATTR_UNUSED(q), int* ATTR_UNUSED(was_ratelimited))
976 {
977 	log_assert(0);
978 	return 0;
979 }
980 
981 void
982 worker_alloc_cleanup(void* ATTR_UNUSED(arg))
983 {
984 	log_assert(0);
985 }
986 
987 void worker_stat_timer_cb(void* ATTR_UNUSED(arg))
988 {
989 	log_assert(0);
990 }
991 
992 void worker_probe_timer_cb(void* ATTR_UNUSED(arg))
993 {
994 	log_assert(0);
995 }
996 
997 void worker_start_accept(void* ATTR_UNUSED(arg))
998 {
999 	log_assert(0);
1000 }
1001 
1002 void worker_stop_accept(void* ATTR_UNUSED(arg))
1003 {
1004 	log_assert(0);
1005 }
1006 
1007 int order_lock_cmp(const void* ATTR_UNUSED(e1), const void* ATTR_UNUSED(e2))
1008 {
1009 	log_assert(0);
1010 	return 0;
1011 }
1012 
1013 int
1014 codeline_cmp(const void* ATTR_UNUSED(a), const void* ATTR_UNUSED(b))
1015 {
1016 	log_assert(0);
1017 	return 0;
1018 }
1019 
1020 int replay_var_compare(const void* ATTR_UNUSED(a), const void* ATTR_UNUSED(b))
1021 {
1022         log_assert(0);
1023         return 0;
1024 }
1025 
1026 void remote_get_opt_ssl(char* ATTR_UNUSED(str), void* ATTR_UNUSED(arg))
1027 {
1028         log_assert(0);
1029 }
1030 
1031 #ifdef UB_ON_WINDOWS
1032 void
1033 worker_win_stop_cb(int ATTR_UNUSED(fd), short ATTR_UNUSED(ev), void*
1034         ATTR_UNUSED(arg)) {
1035         log_assert(0);
1036 }
1037 
1038 void
1039 wsvc_cron_cb(void* ATTR_UNUSED(arg))
1040 {
1041         log_assert(0);
1042 }
1043 #endif /* UB_ON_WINDOWS */
1044 
1045 #ifdef USE_DNSTAP
1046 void dtio_tap_callback(int ATTR_UNUSED(fd), short ATTR_UNUSED(ev),
1047 	void* ATTR_UNUSED(arg))
1048 {
1049 	log_assert(0);
1050 }
1051 #endif
1052 
1053 #ifdef USE_DNSTAP
1054 void dtio_mainfdcallback(int ATTR_UNUSED(fd), short ATTR_UNUSED(ev),
1055 	void* ATTR_UNUSED(arg))
1056 {
1057 	log_assert(0);
1058 }
1059 #endif
1060