xref: /freebsd/contrib/unbound/libunbound/libworker.c (revision 87b759f0fa1f7554d50ce640c40138512bbded44)
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 			ATTR_FALLTHROUGH
296 			/* fallthrough */
297 		case UB_LIBCMD_QUIT:
298 			free(msg);
299 			comm_base_exit(w->base);
300 			break;
301 		case UB_LIBCMD_NEWQUERY:
302 			handle_newq(w, msg, len);
303 			break;
304 		case UB_LIBCMD_CANCEL:
305 			handle_cancel(w, msg, len);
306 			break;
307 	}
308 }
309 
310 /** handle control command coming into server */
311 void
312 libworker_handle_control_cmd(struct tube* ATTR_UNUSED(tube),
313 	uint8_t* msg, size_t len, int err, void* arg)
314 {
315 	struct libworker* w = (struct libworker*)arg;
316 
317 	if(err != 0) {
318 		free(msg);
319 		/* it is of no use to go on, exit */
320 		comm_base_exit(w->base);
321 		return;
322 	}
323 	libworker_do_cmd(w, msg, len); /* also frees the buf */
324 }
325 
326 /** the background thread func */
327 static void*
328 libworker_dobg(void* arg)
329 {
330 	/* setup */
331 	uint32_t m;
332 	struct libworker* w = (struct libworker*)arg;
333 	struct ub_ctx* ctx;
334 	if(!w) {
335 		log_err("libunbound bg worker init failed, nomem");
336 		return NULL;
337 	}
338 	ctx = w->ctx;
339 	log_thread_set(&w->thread_num);
340 #ifdef THREADS_DISABLED
341 	/* we are forked */
342 	w->is_bg_thread = 0;
343 	/* close non-used parts of the pipes */
344 	tube_close_write(ctx->qq_pipe);
345 	tube_close_read(ctx->rr_pipe);
346 #endif
347 	if(!tube_setup_bg_listen(ctx->qq_pipe, w->base,
348 		libworker_handle_control_cmd, w)) {
349 		log_err("libunbound bg worker init failed, no bglisten");
350 		return NULL;
351 	}
352 	if(!tube_setup_bg_write(ctx->rr_pipe, w->base)) {
353 		log_err("libunbound bg worker init failed, no bgwrite");
354 		return NULL;
355 	}
356 
357 	/* do the work */
358 	comm_base_dispatch(w->base);
359 
360 	/* cleanup */
361 	m = UB_LIBCMD_QUIT;
362 	w->want_quit = 1;
363 	tube_remove_bg_listen(w->ctx->qq_pipe);
364 	tube_remove_bg_write(w->ctx->rr_pipe);
365 	libworker_delete(w);
366 	(void)tube_write_msg(ctx->rr_pipe, (uint8_t*)&m,
367 		(uint32_t)sizeof(m), 0);
368 #ifdef THREADS_DISABLED
369 	/* close pipes from forked process before exit */
370 	tube_close_read(ctx->qq_pipe);
371 	tube_close_write(ctx->rr_pipe);
372 #endif
373 	return NULL;
374 }
375 
376 int libworker_bg(struct ub_ctx* ctx)
377 {
378 	struct libworker* w;
379 	/* fork or threadcreate */
380 	lock_basic_lock(&ctx->cfglock);
381 	if(ctx->dothread) {
382 		lock_basic_unlock(&ctx->cfglock);
383 		w = libworker_setup(ctx, 1, NULL);
384 		if(!w) return UB_NOMEM;
385 		w->is_bg_thread = 1;
386 		ctx->thread_worker = w;
387 #ifdef ENABLE_LOCK_CHECKS
388 		w->thread_num = 1; /* for nicer DEBUG checklocks */
389 #endif
390 		ub_thread_create(&ctx->bg_tid, libworker_dobg, w);
391 	} else {
392 		lock_basic_unlock(&ctx->cfglock);
393 #ifndef HAVE_FORK
394 		/* no fork on windows */
395 		return UB_FORKFAIL;
396 #else /* HAVE_FORK */
397 		switch((ctx->bg_pid=fork())) {
398 			case 0:
399 				w = libworker_setup(ctx, 1, NULL);
400 				if(!w) fatal_exit("out of memory");
401 				/* close non-used parts of the pipes */
402 				tube_close_write(ctx->qq_pipe);
403 				tube_close_read(ctx->rr_pipe);
404 				(void)libworker_dobg(w);
405 				exit(0);
406 				break;
407 			case -1:
408 				return UB_FORKFAIL;
409 			default:
410 				/* close non-used parts, so that the worker
411 				 * bgprocess gets 'pipe closed' when the
412 				 * main process exits */
413 				tube_close_read(ctx->qq_pipe);
414 				tube_close_write(ctx->rr_pipe);
415 				break;
416 		}
417 #endif /* HAVE_FORK */
418 	}
419 	return UB_NOERROR;
420 }
421 
422 /** insert canonname */
423 static int
424 fill_canon(struct ub_result* res, uint8_t* s)
425 {
426 	char buf[255+2];
427 	dname_str(s, buf);
428 	res->canonname = strdup(buf);
429 	return res->canonname != 0;
430 }
431 
432 /** fill data into result */
433 static int
434 fill_res(struct ub_result* res, struct ub_packed_rrset_key* answer,
435 	uint8_t* finalcname, struct query_info* rq, struct reply_info* rep)
436 {
437 	size_t i;
438 	struct packed_rrset_data* data;
439 	res->ttl = 0;
440 	if(!answer) {
441 		if(finalcname) {
442 			if(!fill_canon(res, finalcname))
443 				return 0; /* out of memory */
444 		}
445 		if(rep->rrset_count != 0)
446 			res->ttl = (int)rep->ttl;
447 		res->data = (char**)calloc(1, sizeof(char*));
448 		if(!res->data)
449 			return 0; /* out of memory */
450 		res->len = (int*)calloc(1, sizeof(int));
451 		if(!res->len) {
452 			free(res->data);
453 			res->data = NULL;
454 			return 0; /* out of memory */
455 		}
456 		return 1;
457 	}
458 	data = (struct packed_rrset_data*)answer->entry.data;
459 	if(query_dname_compare(rq->qname, answer->rk.dname) != 0) {
460 		if(!fill_canon(res, answer->rk.dname))
461 			return 0; /* out of memory */
462 	} else	res->canonname = NULL;
463 	res->data = (char**)calloc(data->count+1, sizeof(char*));
464 	if(!res->data)
465 		return 0; /* out of memory */
466 	res->len = (int*)calloc(data->count+1, sizeof(int));
467 	if(!res->len) {
468 		free(res->data);
469 		res->data = NULL;
470 		return 0; /* out of memory */
471 	}
472 	for(i=0; i<data->count; i++) {
473 		/* remove rdlength from rdata */
474 		res->len[i] = (int)(data->rr_len[i] - 2);
475 		res->data[i] = memdup(data->rr_data[i]+2, (size_t)res->len[i]);
476 		if(!res->data[i]) {
477 			size_t j;
478 			for(j=0; j<i; j++) {
479 				free(res->data[j]);
480 				res->data[j] = NULL;
481 			}
482 			free(res->data);
483 			res->data = NULL;
484 			free(res->len);
485 			res->len = NULL;
486 			return 0; /* out of memory */
487 		}
488 	}
489 	/* ttl for positive answers, from CNAME and answer RRs */
490 	if(data->count != 0) {
491 		size_t j;
492 		res->ttl = (int)data->ttl;
493 		for(j=0; j<rep->an_numrrsets; j++) {
494 			struct packed_rrset_data* d =
495 				(struct packed_rrset_data*)rep->rrsets[j]->
496 				entry.data;
497 			if((int)d->ttl < res->ttl)
498 				res->ttl = (int)d->ttl;
499 		}
500 	}
501 	/* ttl for negative answers */
502 	if(data->count == 0 && rep->rrset_count != 0)
503 		res->ttl = (int)rep->ttl;
504 	res->data[data->count] = NULL;
505 	res->len[data->count] = 0;
506 	return 1;
507 }
508 
509 /** fill result from parsed message, on error fills servfail */
510 void
511 libworker_enter_result(struct ub_result* res, sldns_buffer* buf,
512 	struct regional* temp, enum sec_status msg_security)
513 {
514 	struct query_info rq;
515 	struct reply_info* rep;
516 	res->rcode = LDNS_RCODE_SERVFAIL;
517 	rep = parse_reply_in_temp_region(buf, temp, &rq);
518 	if(!rep) {
519 		log_err("cannot parse buf");
520 		return; /* error parsing buf, or out of memory */
521 	}
522 	if(!fill_res(res, reply_find_answer_rrset(&rq, rep),
523 		reply_find_final_cname_target(&rq, rep), &rq, rep))
524 		return; /* out of memory */
525 	/* rcode, havedata, nxdomain, secure, bogus */
526 	res->rcode = (int)FLAGS_GET_RCODE(rep->flags);
527 	if(res->data && res->data[0])
528 		res->havedata = 1;
529 	if(res->rcode == LDNS_RCODE_NXDOMAIN)
530 		res->nxdomain = 1;
531 	if(msg_security == sec_status_secure)
532 		res->secure = 1;
533 	if(msg_security == sec_status_bogus ||
534 		msg_security == sec_status_secure_sentinel_fail)
535 		res->bogus = 1;
536 }
537 
538 /** fillup fg results */
539 static void
540 libworker_fillup_fg(struct ctx_query* q, int rcode, sldns_buffer* buf,
541 	enum sec_status s, char* why_bogus, int was_ratelimited)
542 {
543 	q->res->was_ratelimited = was_ratelimited;
544 	if(why_bogus)
545 		q->res->why_bogus = strdup(why_bogus);
546 	if(rcode != 0) {
547 		q->res->rcode = rcode;
548 		q->msg_security = s;
549 		return;
550 	}
551 
552 	q->res->rcode = LDNS_RCODE_SERVFAIL;
553 	q->msg_security = sec_status_unchecked;
554 	q->msg = memdup(sldns_buffer_begin(buf), sldns_buffer_limit(buf));
555 	q->msg_len = sldns_buffer_limit(buf);
556 	if(!q->msg) {
557 		return; /* the error is in the rcode */
558 	}
559 
560 	/* canonname and results */
561 	q->msg_security = s;
562 	libworker_enter_result(q->res, buf, q->w->env->scratch, s);
563 }
564 
565 void
566 libworker_fg_done_cb(void* arg, int rcode, sldns_buffer* buf, enum sec_status s,
567 	char* why_bogus, int was_ratelimited)
568 {
569 	struct ctx_query* q = (struct ctx_query*)arg;
570 	/* fg query is done; exit comm base */
571 	comm_base_exit(q->w->base);
572 
573 	libworker_fillup_fg(q, rcode, buf, s, why_bogus, was_ratelimited);
574 }
575 
576 /** setup qinfo and edns */
577 static int
578 setup_qinfo_edns(struct libworker* w, struct ctx_query* q,
579 	struct query_info* qinfo, struct edns_data* edns)
580 {
581 	qinfo->qtype = (uint16_t)q->res->qtype;
582 	qinfo->qclass = (uint16_t)q->res->qclass;
583 	qinfo->local_alias = NULL;
584 	qinfo->qname = sldns_str2wire_dname(q->res->qname, &qinfo->qname_len);
585 	if(!qinfo->qname) {
586 		return 0;
587 	}
588 	edns->edns_present = 1;
589 	edns->ext_rcode = 0;
590 	edns->edns_version = 0;
591 	edns->bits = EDNS_DO;
592 	edns->opt_list_in = NULL;
593 	edns->opt_list_out = NULL;
594 	edns->opt_list_inplace_cb_out = NULL;
595 	edns->padding_block_size = 0;
596 	edns->cookie_present = 0;
597 	edns->cookie_valid = 0;
598 	if(sldns_buffer_capacity(w->back->udp_buff) < 65535)
599 		edns->udp_size = (uint16_t)sldns_buffer_capacity(
600 			w->back->udp_buff);
601 	else	edns->udp_size = 65535;
602 	return 1;
603 }
604 
605 int libworker_fg(struct ub_ctx* ctx, struct ctx_query* q)
606 {
607 	struct libworker* w = libworker_setup(ctx, 0, NULL);
608 	uint16_t qflags, qid;
609 	struct query_info qinfo;
610 	struct edns_data edns;
611 	if(!w)
612 		return UB_INITFAIL;
613 	if(!setup_qinfo_edns(w, q, &qinfo, &edns)) {
614 		libworker_delete(w);
615 		return UB_SYNTAX;
616 	}
617 	qid = 0;
618 	qflags = BIT_RD;
619 	q->w = w;
620 	/* see if there is a fixed answer */
621 	sldns_buffer_write_u16_at(w->back->udp_buff, 0, qid);
622 	sldns_buffer_write_u16_at(w->back->udp_buff, 2, qflags);
623 	if(local_zones_answer(ctx->local_zones, w->env, &qinfo, &edns,
624 		w->back->udp_buff, w->env->scratch, NULL, NULL, 0, NULL, 0,
625 		NULL, 0, NULL, 0, NULL)) {
626 		regional_free_all(w->env->scratch);
627 		libworker_fillup_fg(q, LDNS_RCODE_NOERROR,
628 			w->back->udp_buff, sec_status_insecure, NULL, 0);
629 		libworker_delete(w);
630 		free(qinfo.qname);
631 		return UB_NOERROR;
632 	}
633 	if(ctx->env->auth_zones && auth_zones_answer(ctx->env->auth_zones,
634 		w->env, &qinfo, &edns, NULL, w->back->udp_buff, w->env->scratch)) {
635 		regional_free_all(w->env->scratch);
636 		libworker_fillup_fg(q, LDNS_RCODE_NOERROR,
637 			w->back->udp_buff, sec_status_insecure, NULL, 0);
638 		libworker_delete(w);
639 		free(qinfo.qname);
640 		return UB_NOERROR;
641 	}
642 	/* process new query */
643 	if(!mesh_new_callback(w->env->mesh, &qinfo, qflags, &edns,
644 		w->back->udp_buff, qid, libworker_fg_done_cb, q, 0)) {
645 		free(qinfo.qname);
646 		return UB_NOMEM;
647 	}
648 	free(qinfo.qname);
649 
650 	/* wait for reply */
651 	comm_base_dispatch(w->base);
652 
653 	libworker_delete(w);
654 	return UB_NOERROR;
655 }
656 
657 void
658 libworker_event_done_cb(void* arg, int rcode, sldns_buffer* buf,
659 	enum sec_status s, char* why_bogus, int was_ratelimited)
660 {
661 	struct ctx_query* q = (struct ctx_query*)arg;
662 	ub_event_callback_type cb = q->cb_event;
663 	void* cb_arg = q->cb_arg;
664 	int cancelled = q->cancelled;
665 
666 	/* delete it now */
667 	struct ub_ctx* ctx = q->w->ctx;
668 	lock_basic_lock(&ctx->cfglock);
669 	(void)rbtree_delete(&ctx->queries, q->node.key);
670 	ctx->num_async--;
671 	context_query_delete(q);
672 	lock_basic_unlock(&ctx->cfglock);
673 
674 	if(!cancelled) {
675 		/* call callback */
676 		int sec = 0;
677 		if(s == sec_status_bogus)
678 			sec = 1;
679 		else if(s == sec_status_secure)
680 			sec = 2;
681 		(*cb)(cb_arg, rcode, (buf?(void*)sldns_buffer_begin(buf):NULL),
682 			(buf?(int)sldns_buffer_limit(buf):0), sec, why_bogus, was_ratelimited);
683 	}
684 }
685 
686 int libworker_attach_mesh(struct ub_ctx* ctx, struct ctx_query* q,
687 	int* async_id)
688 {
689 	struct libworker* w = ctx->event_worker;
690 	uint16_t qflags, qid;
691 	struct query_info qinfo;
692 	struct edns_data edns;
693 	if(!w)
694 		return UB_INITFAIL;
695 	if(!setup_qinfo_edns(w, q, &qinfo, &edns))
696 		return UB_SYNTAX;
697 	qid = 0;
698 	qflags = BIT_RD;
699 	q->w = w;
700 	/* see if there is a fixed answer */
701 	sldns_buffer_write_u16_at(w->back->udp_buff, 0, qid);
702 	sldns_buffer_write_u16_at(w->back->udp_buff, 2, qflags);
703 	if(local_zones_answer(ctx->local_zones, w->env, &qinfo, &edns,
704 		w->back->udp_buff, w->env->scratch, NULL, NULL, 0, NULL, 0,
705 		NULL, 0, NULL, 0, NULL)) {
706 		regional_free_all(w->env->scratch);
707 		free(qinfo.qname);
708 		libworker_event_done_cb(q, LDNS_RCODE_NOERROR,
709 			w->back->udp_buff, sec_status_insecure, NULL, 0);
710 		return UB_NOERROR;
711 	}
712 	if(ctx->env->auth_zones && auth_zones_answer(ctx->env->auth_zones,
713 		w->env, &qinfo, &edns, NULL, w->back->udp_buff, w->env->scratch)) {
714 		regional_free_all(w->env->scratch);
715 		free(qinfo.qname);
716 		libworker_event_done_cb(q, LDNS_RCODE_NOERROR,
717 			w->back->udp_buff, sec_status_insecure, NULL, 0);
718 		return UB_NOERROR;
719 	}
720 	/* process new query */
721 	if(async_id)
722 		*async_id = q->querynum;
723 	if(!mesh_new_callback(w->env->mesh, &qinfo, qflags, &edns,
724 		w->back->udp_buff, qid, libworker_event_done_cb, q, 0)) {
725 		free(qinfo.qname);
726 		return UB_NOMEM;
727 	}
728 	free(qinfo.qname);
729 	return UB_NOERROR;
730 }
731 
732 /** add result to the bg worker result queue */
733 static void
734 add_bg_result(struct libworker* w, struct ctx_query* q, sldns_buffer* pkt,
735 	int err, char* reason, int was_ratelimited)
736 {
737 	uint8_t* msg = NULL;
738 	uint32_t len = 0;
739 
740 	if(w->want_quit) {
741 		context_query_delete(q);
742 		return;
743 	}
744 	/* serialize and delete unneeded q */
745 	if(w->is_bg_thread) {
746 		lock_basic_lock(&w->ctx->cfglock);
747 		if(reason)
748 			q->res->why_bogus = strdup(reason);
749 		q->res->was_ratelimited = was_ratelimited;
750 		if(pkt) {
751 			q->msg_len = sldns_buffer_remaining(pkt);
752 			q->msg = memdup(sldns_buffer_begin(pkt), q->msg_len);
753 			if(!q->msg) {
754 				msg = context_serialize_answer(q, UB_NOMEM, NULL, &len);
755 			} else {
756 				msg = context_serialize_answer(q, err, NULL, &len);
757 			}
758 		} else {
759 			msg = context_serialize_answer(q, err, NULL, &len);
760 		}
761 		lock_basic_unlock(&w->ctx->cfglock);
762 	} else {
763 		if(reason)
764 			q->res->why_bogus = strdup(reason);
765 		q->res->was_ratelimited = was_ratelimited;
766 		msg = context_serialize_answer(q, err, pkt, &len);
767 		(void)rbtree_delete(&w->ctx->queries, q->node.key);
768 		w->ctx->num_async--;
769 		context_query_delete(q);
770 	}
771 
772 	if(!msg) {
773 		log_err("out of memory for async answer");
774 		return;
775 	}
776 	if(!tube_queue_item(w->ctx->rr_pipe, msg, len)) {
777 		log_err("out of memory for async answer");
778 		return;
779 	}
780 }
781 
782 void
783 libworker_bg_done_cb(void* arg, int rcode, sldns_buffer* buf, enum sec_status s,
784 	char* why_bogus, int was_ratelimited)
785 {
786 	struct ctx_query* q = (struct ctx_query*)arg;
787 
788 	if(q->cancelled || q->w->back->want_to_quit) {
789 		if(q->w->is_bg_thread) {
790 			/* delete it now */
791 			struct ub_ctx* ctx = q->w->ctx;
792 			lock_basic_lock(&ctx->cfglock);
793 			(void)rbtree_delete(&ctx->queries, q->node.key);
794 			ctx->num_async--;
795 			context_query_delete(q);
796 			lock_basic_unlock(&ctx->cfglock);
797 		}
798 		/* cancelled, do not give answer */
799 		return;
800 	}
801 	q->msg_security = s;
802 	if(!buf) {
803 		buf = q->w->env->scratch_buffer;
804 	}
805 	if(rcode != 0) {
806 		error_encode(buf, rcode, NULL, 0, BIT_RD, NULL);
807 	}
808 	add_bg_result(q->w, q, buf, UB_NOERROR, why_bogus, was_ratelimited);
809 }
810 
811 
812 /** handle new query command for bg worker */
813 static void
814 handle_newq(struct libworker* w, uint8_t* buf, uint32_t len)
815 {
816 	uint16_t qflags, qid;
817 	struct query_info qinfo;
818 	struct edns_data edns;
819 	struct ctx_query* q;
820 	if(w->is_bg_thread) {
821 		lock_basic_lock(&w->ctx->cfglock);
822 		q = context_lookup_new_query(w->ctx, buf, len);
823 		lock_basic_unlock(&w->ctx->cfglock);
824 	} else {
825 		q = context_deserialize_new_query(w->ctx, buf, len);
826 	}
827 	free(buf);
828 	if(!q) {
829 		log_err("failed to deserialize newq");
830 		return;
831 	}
832 	if(!setup_qinfo_edns(w, q, &qinfo, &edns)) {
833 		add_bg_result(w, q, NULL, UB_SYNTAX, NULL, 0);
834 		return;
835 	}
836 	qid = 0;
837 	qflags = BIT_RD;
838 	/* see if there is a fixed answer */
839 	sldns_buffer_write_u16_at(w->back->udp_buff, 0, qid);
840 	sldns_buffer_write_u16_at(w->back->udp_buff, 2, qflags);
841 	if(local_zones_answer(w->ctx->local_zones, w->env, &qinfo, &edns,
842 		w->back->udp_buff, w->env->scratch, NULL, NULL, 0, NULL, 0,
843 		NULL, 0, NULL, 0, NULL)) {
844 		regional_free_all(w->env->scratch);
845 		q->msg_security = sec_status_insecure;
846 		add_bg_result(w, q, w->back->udp_buff, UB_NOERROR, NULL, 0);
847 		free(qinfo.qname);
848 		return;
849 	}
850 	if(w->ctx->env->auth_zones && auth_zones_answer(w->ctx->env->auth_zones,
851 		w->env, &qinfo, &edns, NULL, w->back->udp_buff, w->env->scratch)) {
852 		regional_free_all(w->env->scratch);
853 		q->msg_security = sec_status_insecure;
854 		add_bg_result(w, q, w->back->udp_buff, UB_NOERROR, NULL, 0);
855 		free(qinfo.qname);
856 		return;
857 	}
858 	q->w = w;
859 	/* process new query */
860 	if(!mesh_new_callback(w->env->mesh, &qinfo, qflags, &edns,
861 		w->back->udp_buff, qid, libworker_bg_done_cb, q, 0)) {
862 		add_bg_result(w, q, NULL, UB_NOMEM, NULL, 0);
863 	}
864 	free(qinfo.qname);
865 }
866 
867 void libworker_alloc_cleanup(void* arg)
868 {
869 	struct libworker* w = (struct libworker*)arg;
870 	slabhash_clear(&w->env->rrset_cache->table);
871         slabhash_clear(w->env->msg_cache);
872 }
873 
874 struct outbound_entry* libworker_send_query(struct query_info* qinfo,
875 	uint16_t flags, int dnssec, int want_dnssec, int nocaps,
876 	int check_ratelimit,
877 	struct sockaddr_storage* addr, socklen_t addrlen, uint8_t* zone,
878 	size_t zonelen, int tcp_upstream, int ssl_upstream, char* tls_auth_name,
879 	struct module_qstate* q, int* was_ratelimited)
880 {
881 	struct libworker* w = (struct libworker*)q->env->worker;
882 	struct outbound_entry* e = (struct outbound_entry*)regional_alloc(
883 		q->region, sizeof(*e));
884 	if(!e)
885 		return NULL;
886 	e->qstate = q;
887 	e->qsent = outnet_serviced_query(w->back, qinfo, flags, dnssec,
888 		want_dnssec, nocaps, check_ratelimit, tcp_upstream, ssl_upstream,
889 		tls_auth_name, addr, addrlen, zone, zonelen, q,
890 		libworker_handle_service_reply, e, w->back->udp_buff, q->env,
891 		was_ratelimited);
892 	if(!e->qsent) {
893 		return NULL;
894 	}
895 	return e;
896 }
897 
898 int
899 libworker_handle_service_reply(struct comm_point* c, void* arg, int error,
900         struct comm_reply* reply_info)
901 {
902 	struct outbound_entry* e = (struct outbound_entry*)arg;
903 	struct libworker* lw = (struct libworker*)e->qstate->env->worker;
904 
905 	if(error != 0) {
906 		mesh_report_reply(lw->env->mesh, e, reply_info, error);
907 		return 0;
908 	}
909 	/* sanity check. */
910 	if(!LDNS_QR_WIRE(sldns_buffer_begin(c->buffer))
911 		|| LDNS_OPCODE_WIRE(sldns_buffer_begin(c->buffer)) !=
912 			LDNS_PACKET_QUERY
913 		|| LDNS_QDCOUNT(sldns_buffer_begin(c->buffer)) > 1) {
914 		/* error becomes timeout for the module as if this reply
915 		 * never arrived. */
916 		mesh_report_reply(lw->env->mesh, e, reply_info,
917 			NETEVENT_TIMEOUT);
918 		return 0;
919 	}
920 	mesh_report_reply(lw->env->mesh,  e, reply_info, NETEVENT_NOERROR);
921 	return 0;
922 }
923 
924 /* --- fake callbacks for fptr_wlist to work --- */
925 void worker_handle_control_cmd(struct tube* ATTR_UNUSED(tube),
926 	uint8_t* ATTR_UNUSED(buffer), size_t ATTR_UNUSED(len),
927 	int ATTR_UNUSED(error), void* ATTR_UNUSED(arg))
928 {
929 	log_assert(0);
930 }
931 
932 int worker_handle_request(struct comm_point* ATTR_UNUSED(c),
933 	void* ATTR_UNUSED(arg), int ATTR_UNUSED(error),
934         struct comm_reply* ATTR_UNUSED(repinfo))
935 {
936 	log_assert(0);
937 	return 0;
938 }
939 
940 int worker_handle_service_reply(struct comm_point* ATTR_UNUSED(c),
941 	void* ATTR_UNUSED(arg), int ATTR_UNUSED(error),
942         struct comm_reply* ATTR_UNUSED(reply_info))
943 {
944 	log_assert(0);
945 	return 0;
946 }
947 
948 int remote_accept_callback(struct comm_point* ATTR_UNUSED(c),
949 	void* ATTR_UNUSED(arg), int ATTR_UNUSED(error),
950         struct comm_reply* ATTR_UNUSED(repinfo))
951 {
952 	log_assert(0);
953 	return 0;
954 }
955 
956 int remote_control_callback(struct comm_point* ATTR_UNUSED(c),
957 	void* ATTR_UNUSED(arg), int ATTR_UNUSED(error),
958         struct comm_reply* ATTR_UNUSED(repinfo))
959 {
960 	log_assert(0);
961 	return 0;
962 }
963 
964 void worker_sighandler(int ATTR_UNUSED(sig), void* ATTR_UNUSED(arg))
965 {
966 	log_assert(0);
967 }
968 
969 struct outbound_entry* worker_send_query(struct query_info* ATTR_UNUSED(qinfo),
970 	uint16_t ATTR_UNUSED(flags), int ATTR_UNUSED(dnssec),
971 	int ATTR_UNUSED(want_dnssec), int ATTR_UNUSED(nocaps),
972 	int ATTR_UNUSED(check_ratelimit),
973 	struct sockaddr_storage* ATTR_UNUSED(addr), socklen_t ATTR_UNUSED(addrlen),
974 	uint8_t* ATTR_UNUSED(zone), size_t ATTR_UNUSED(zonelen), int ATTR_UNUSED(tcp_upstream),
975 	int ATTR_UNUSED(ssl_upstream), char* ATTR_UNUSED(tls_auth_name),
976 	struct module_qstate* ATTR_UNUSED(q), int* ATTR_UNUSED(was_ratelimited))
977 {
978 	log_assert(0);
979 	return 0;
980 }
981 
982 void
983 worker_alloc_cleanup(void* ATTR_UNUSED(arg))
984 {
985 	log_assert(0);
986 }
987 
988 void worker_stat_timer_cb(void* ATTR_UNUSED(arg))
989 {
990 	log_assert(0);
991 }
992 
993 void worker_probe_timer_cb(void* ATTR_UNUSED(arg))
994 {
995 	log_assert(0);
996 }
997 
998 void worker_start_accept(void* ATTR_UNUSED(arg))
999 {
1000 	log_assert(0);
1001 }
1002 
1003 void worker_stop_accept(void* ATTR_UNUSED(arg))
1004 {
1005 	log_assert(0);
1006 }
1007 
1008 int order_lock_cmp(const void* ATTR_UNUSED(e1), const void* ATTR_UNUSED(e2))
1009 {
1010 	log_assert(0);
1011 	return 0;
1012 }
1013 
1014 int
1015 codeline_cmp(const void* ATTR_UNUSED(a), const void* ATTR_UNUSED(b))
1016 {
1017 	log_assert(0);
1018 	return 0;
1019 }
1020 
1021 int replay_var_compare(const void* ATTR_UNUSED(a), const void* ATTR_UNUSED(b))
1022 {
1023         log_assert(0);
1024         return 0;
1025 }
1026 
1027 void remote_get_opt_ssl(char* ATTR_UNUSED(str), void* ATTR_UNUSED(arg))
1028 {
1029         log_assert(0);
1030 }
1031 
1032 #ifdef UB_ON_WINDOWS
1033 void
1034 worker_win_stop_cb(int ATTR_UNUSED(fd), short ATTR_UNUSED(ev), void*
1035         ATTR_UNUSED(arg)) {
1036         log_assert(0);
1037 }
1038 
1039 void
1040 wsvc_cron_cb(void* ATTR_UNUSED(arg))
1041 {
1042         log_assert(0);
1043 }
1044 #endif /* UB_ON_WINDOWS */
1045 
1046 #ifdef USE_DNSTAP
1047 void dtio_tap_callback(int ATTR_UNUSED(fd), short ATTR_UNUSED(ev),
1048 	void* ATTR_UNUSED(arg))
1049 {
1050 	log_assert(0);
1051 }
1052 #endif
1053 
1054 #ifdef USE_DNSTAP
1055 void dtio_mainfdcallback(int ATTR_UNUSED(fd), short ATTR_UNUSED(ev),
1056 	void* ATTR_UNUSED(arg))
1057 {
1058 	log_assert(0);
1059 }
1060 #endif
1061