xref: /netbsd-src/external/mpl/dhcp/bind/dist/lib/dns/client.c (revision 4afad4b7fa6d4a0d3dedf41d1587a7250710ae54)
1 /*	$NetBSD: client.c,v 1.1 2024/02/18 20:57:30 christos Exp $	*/
2 
3 /*
4  * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
5  *
6  * SPDX-License-Identifier: MPL-2.0
7  *
8  * This Source Code Form is subject to the terms of the Mozilla Public
9  * License, v. 2.0. If a copy of the MPL was not distributed with this
10  * file, you can obtain one at https://mozilla.org/MPL/2.0/.
11  *
12  * See the COPYRIGHT file distributed with this work for additional
13  * information regarding copyright ownership.
14  */
15 
16 #include <stdbool.h>
17 #include <stddef.h>
18 
19 #include <isc/app.h>
20 #include <isc/buffer.h>
21 #include <isc/md.h>
22 #include <isc/mem.h>
23 #include <isc/mutex.h>
24 #include <isc/portset.h>
25 #include <isc/refcount.h>
26 #include <isc/safe.h>
27 #include <isc/sockaddr.h>
28 #include <isc/socket.h>
29 #include <isc/task.h>
30 #include <isc/timer.h>
31 #include <isc/util.h>
32 
33 #include <dns/adb.h>
34 #include <dns/client.h>
35 #include <dns/db.h>
36 #include <dns/dispatch.h>
37 #include <dns/events.h>
38 #include <dns/forward.h>
39 #include <dns/keytable.h>
40 #include <dns/message.h>
41 #include <dns/name.h>
42 #include <dns/rdata.h>
43 #include <dns/rdatalist.h>
44 #include <dns/rdataset.h>
45 #include <dns/rdatasetiter.h>
46 #include <dns/rdatastruct.h>
47 #include <dns/rdatatype.h>
48 #include <dns/request.h>
49 #include <dns/resolver.h>
50 #include <dns/result.h>
51 #include <dns/tsec.h>
52 #include <dns/tsig.h>
53 #include <dns/view.h>
54 
55 #include <dst/dst.h>
56 
57 #define DNS_CLIENT_MAGIC    ISC_MAGIC('D', 'N', 'S', 'c')
58 #define DNS_CLIENT_VALID(c) ISC_MAGIC_VALID(c, DNS_CLIENT_MAGIC)
59 
60 #define RCTX_MAGIC    ISC_MAGIC('R', 'c', 't', 'x')
61 #define RCTX_VALID(c) ISC_MAGIC_VALID(c, RCTX_MAGIC)
62 
63 #define REQCTX_MAGIC	ISC_MAGIC('R', 'q', 'c', 'x')
64 #define REQCTX_VALID(c) ISC_MAGIC_VALID(c, REQCTX_MAGIC)
65 
66 #define UCTX_MAGIC    ISC_MAGIC('U', 'c', 't', 'x')
67 #define UCTX_VALID(c) ISC_MAGIC_VALID(c, UCTX_MAGIC)
68 
69 #define MAX_RESTARTS 16
70 
71 #ifdef TUNE_LARGE
72 #define RESOLVER_NTASKS 523
73 #else /* ifdef TUNE_LARGE */
74 #define RESOLVER_NTASKS 31
75 #endif /* TUNE_LARGE */
76 
77 #define CHECK(r)                             \
78 	do {                                 \
79 		result = (r);                \
80 		if (result != ISC_R_SUCCESS) \
81 			goto cleanup;        \
82 	} while (0)
83 
84 /*%
85  * DNS client object
86  */
87 struct dns_client {
88 	/* Unlocked */
89 	unsigned int magic;
90 	unsigned int attributes;
91 	isc_mutex_t lock;
92 	isc_mem_t *mctx;
93 	isc_appctx_t *actx;
94 	isc_taskmgr_t *taskmgr;
95 	isc_task_t *task;
96 	isc_socketmgr_t *socketmgr;
97 	isc_timermgr_t *timermgr;
98 	dns_dispatchmgr_t *dispatchmgr;
99 	dns_dispatch_t *dispatchv4;
100 	dns_dispatch_t *dispatchv6;
101 
102 	unsigned int update_timeout;
103 	unsigned int update_udptimeout;
104 	unsigned int update_udpretries;
105 	unsigned int find_timeout;
106 	unsigned int find_udpretries;
107 
108 	isc_refcount_t references;
109 
110 	/* Locked */
111 	dns_viewlist_t viewlist;
112 	ISC_LIST(struct resctx) resctxs;
113 	ISC_LIST(struct reqctx) reqctxs;
114 	ISC_LIST(struct updatectx) updatectxs;
115 };
116 
117 /*%
118  * Timeout/retry constants for dynamic update borrowed from nsupdate
119  */
120 #define DEF_UPDATE_TIMEOUT    300
121 #define MIN_UPDATE_TIMEOUT    30
122 #define DEF_UPDATE_UDPTIMEOUT 3
123 #define DEF_UPDATE_UDPRETRIES 3
124 
125 #define DEF_FIND_TIMEOUT    5
126 #define DEF_FIND_UDPRETRIES 3
127 
128 #define DNS_CLIENTATTR_OWNCTX 0x01
129 
130 /*%
131  * Internal state for a single name resolution procedure
132  */
133 typedef struct resctx {
134 	/* Unlocked */
135 	unsigned int magic;
136 	isc_mutex_t lock;
137 	dns_client_t *client;
138 	bool want_dnssec;
139 	bool want_validation;
140 	bool want_cdflag;
141 	bool want_tcp;
142 
143 	/* Locked */
144 	ISC_LINK(struct resctx) link;
145 	isc_task_t *task;
146 	dns_view_t *view;
147 	unsigned int restarts;
148 	dns_fixedname_t name;
149 	dns_rdatatype_t type;
150 	dns_fetch_t *fetch;
151 	dns_namelist_t namelist;
152 	isc_result_t result;
153 	dns_clientresevent_t *event;
154 	bool canceled;
155 	dns_rdataset_t *rdataset;
156 	dns_rdataset_t *sigrdataset;
157 } resctx_t;
158 
159 /*%
160  * Argument of an internal event for synchronous name resolution.
161  */
162 typedef struct resarg {
163 	/* Unlocked */
164 	isc_appctx_t *actx;
165 	dns_client_t *client;
166 	isc_mutex_t lock;
167 
168 	/* Locked */
169 	isc_result_t result;
170 	isc_result_t vresult;
171 	dns_namelist_t *namelist;
172 	dns_clientrestrans_t *trans;
173 	bool canceled;
174 } resarg_t;
175 
176 /*%
177  * Internal state for a single DNS request
178  */
179 typedef struct reqctx {
180 	/* Unlocked */
181 	unsigned int magic;
182 	isc_mutex_t lock;
183 	dns_client_t *client;
184 	unsigned int parseoptions;
185 
186 	/* Locked */
187 	ISC_LINK(struct reqctx) link;
188 	bool canceled;
189 	dns_tsigkey_t *tsigkey;
190 	dns_request_t *request;
191 	dns_clientreqevent_t *event;
192 } reqctx_t;
193 
194 /*%
195  * Argument of an internal event for synchronous DNS request.
196  */
197 typedef struct reqarg {
198 	/* Unlocked */
199 	isc_appctx_t *actx;
200 	dns_client_t *client;
201 	isc_mutex_t lock;
202 
203 	/* Locked */
204 	isc_result_t result;
205 	dns_clientreqtrans_t *trans;
206 	bool canceled;
207 } reqarg_t;
208 
209 /*%
210  * Argument of an internal event for synchronous name resolution.
211  */
212 typedef struct updatearg {
213 	/* Unlocked */
214 	isc_appctx_t *actx;
215 	dns_client_t *client;
216 	isc_mutex_t lock;
217 
218 	/* Locked */
219 	isc_result_t result;
220 	dns_clientupdatetrans_t *trans;
221 	bool canceled;
222 } updatearg_t;
223 
224 /*%
225  * Internal state for a single dynamic update procedure
226  */
227 typedef struct updatectx {
228 	/* Unlocked */
229 	unsigned int magic;
230 	isc_mutex_t lock;
231 	dns_client_t *client;
232 	bool want_tcp;
233 
234 	/* Locked */
235 	dns_request_t *updatereq;
236 	dns_request_t *soareq;
237 	dns_clientrestrans_t *restrans;
238 	dns_clientrestrans_t *restrans2;
239 	bool canceled;
240 
241 	/* Task Locked */
242 	ISC_LINK(struct updatectx) link;
243 	dns_clientupdatestate_t state;
244 	dns_rdataclass_t rdclass;
245 	dns_view_t *view;
246 	dns_message_t *updatemsg;
247 	dns_message_t *soaquery;
248 	dns_clientupdateevent_t *event;
249 	dns_tsigkey_t *tsigkey;
250 	dst_key_t *sig0key;
251 	dns_name_t *firstname;
252 	dns_name_t soaqname;
253 	dns_fixedname_t zonefname;
254 	dns_name_t *zonename;
255 	isc_sockaddrlist_t servers;
256 	unsigned int nservers;
257 	isc_sockaddr_t *currentserver;
258 	struct updatectx *bp4;
259 	struct updatectx *bp6;
260 } updatectx_t;
261 
262 static isc_result_t
263 request_soa(updatectx_t *uctx);
264 static void
265 client_resfind(resctx_t *rctx, dns_fetchevent_t *event);
266 static isc_result_t
267 send_update(updatectx_t *uctx);
268 
269 /*
270  * Try honoring the operating system's preferred ephemeral port range.
271  */
272 static isc_result_t
setsourceports(isc_mem_t * mctx,dns_dispatchmgr_t * manager)273 setsourceports(isc_mem_t *mctx, dns_dispatchmgr_t *manager) {
274 	isc_portset_t *v4portset = NULL, *v6portset = NULL;
275 	in_port_t udpport_low, udpport_high;
276 	isc_result_t result;
277 
278 	result = isc_portset_create(mctx, &v4portset);
279 	if (result != ISC_R_SUCCESS) {
280 		goto cleanup;
281 	}
282 	result = isc_net_getudpportrange(AF_INET, &udpport_low, &udpport_high);
283 	if (result != ISC_R_SUCCESS) {
284 		goto cleanup;
285 	}
286 	isc_portset_addrange(v4portset, udpport_low, udpport_high);
287 
288 	result = isc_portset_create(mctx, &v6portset);
289 	if (result != ISC_R_SUCCESS) {
290 		goto cleanup;
291 	}
292 	result = isc_net_getudpportrange(AF_INET6, &udpport_low, &udpport_high);
293 	if (result != ISC_R_SUCCESS) {
294 		goto cleanup;
295 	}
296 	isc_portset_addrange(v6portset, udpport_low, udpport_high);
297 
298 	result = dns_dispatchmgr_setavailports(manager, v4portset, v6portset);
299 
300 cleanup:
301 	if (v4portset != NULL) {
302 		isc_portset_destroy(mctx, &v4portset);
303 	}
304 	if (v6portset != NULL) {
305 		isc_portset_destroy(mctx, &v6portset);
306 	}
307 
308 	return (result);
309 }
310 
311 static isc_result_t
getudpdispatch(int family,dns_dispatchmgr_t * dispatchmgr,isc_socketmgr_t * socketmgr,isc_taskmgr_t * taskmgr,bool is_shared,dns_dispatch_t ** dispp,const isc_sockaddr_t * localaddr)312 getudpdispatch(int family, dns_dispatchmgr_t *dispatchmgr,
313 	       isc_socketmgr_t *socketmgr, isc_taskmgr_t *taskmgr,
314 	       bool is_shared, dns_dispatch_t **dispp,
315 	       const isc_sockaddr_t *localaddr) {
316 	unsigned int attrs, attrmask;
317 	dns_dispatch_t *disp;
318 	unsigned buffersize, maxbuffers, maxrequests, buckets, increment;
319 	isc_result_t result;
320 	isc_sockaddr_t anyaddr;
321 
322 	attrs = 0;
323 	attrs |= DNS_DISPATCHATTR_UDP;
324 	switch (family) {
325 	case AF_INET:
326 		attrs |= DNS_DISPATCHATTR_IPV4;
327 		break;
328 	case AF_INET6:
329 		attrs |= DNS_DISPATCHATTR_IPV6;
330 		break;
331 	default:
332 		UNREACHABLE();
333 	}
334 	attrmask = 0;
335 	attrmask |= DNS_DISPATCHATTR_UDP;
336 	attrmask |= DNS_DISPATCHATTR_TCP;
337 	attrmask |= DNS_DISPATCHATTR_IPV4;
338 	attrmask |= DNS_DISPATCHATTR_IPV6;
339 
340 	if (localaddr == NULL) {
341 		isc_sockaddr_anyofpf(&anyaddr, family);
342 		localaddr = &anyaddr;
343 	}
344 
345 	buffersize = 4096;
346 	maxbuffers = is_shared ? 1000 : 8;
347 	maxrequests = 32768;
348 	buckets = is_shared ? 16411 : 3;
349 	increment = is_shared ? 16433 : 5;
350 
351 	disp = NULL;
352 	result = dns_dispatch_getudp(dispatchmgr, socketmgr, taskmgr, localaddr,
353 				     buffersize, maxbuffers, maxrequests,
354 				     buckets, increment, attrs, attrmask,
355 				     &disp);
356 	if (result == ISC_R_SUCCESS) {
357 		*dispp = disp;
358 	}
359 
360 	return (result);
361 }
362 
363 static isc_result_t
createview(isc_mem_t * mctx,dns_rdataclass_t rdclass,unsigned int options,isc_taskmgr_t * taskmgr,unsigned int ntasks,isc_socketmgr_t * socketmgr,isc_timermgr_t * timermgr,dns_dispatchmgr_t * dispatchmgr,dns_dispatch_t * dispatchv4,dns_dispatch_t * dispatchv6,dns_view_t ** viewp)364 createview(isc_mem_t *mctx, dns_rdataclass_t rdclass, unsigned int options,
365 	   isc_taskmgr_t *taskmgr, unsigned int ntasks,
366 	   isc_socketmgr_t *socketmgr, isc_timermgr_t *timermgr,
367 	   dns_dispatchmgr_t *dispatchmgr, dns_dispatch_t *dispatchv4,
368 	   dns_dispatch_t *dispatchv6, dns_view_t **viewp) {
369 	isc_result_t result;
370 	dns_view_t *view = NULL;
371 	const char *dbtype;
372 
373 	result = dns_view_create(mctx, rdclass, DNS_CLIENTVIEW_NAME, &view);
374 	if (result != ISC_R_SUCCESS) {
375 		return (result);
376 	}
377 
378 	/* Initialize view security roots */
379 	result = dns_view_initsecroots(view, mctx);
380 	if (result != ISC_R_SUCCESS) {
381 		dns_view_detach(&view);
382 		return (result);
383 	}
384 
385 	result = dns_view_createresolver(view, taskmgr, ntasks, 1, socketmgr,
386 					 timermgr, 0, dispatchmgr, dispatchv4,
387 					 dispatchv6);
388 	if (result != ISC_R_SUCCESS) {
389 		dns_view_detach(&view);
390 		return (result);
391 	}
392 
393 	/*
394 	 * Set cache DB.
395 	 * XXX: it may be better if specific DB implementations can be
396 	 * specified via some configuration knob.
397 	 */
398 	if ((options & DNS_CLIENTCREATEOPT_USECACHE) != 0) {
399 		dbtype = "rbt";
400 	} else {
401 		dbtype = "ecdb";
402 	}
403 	result = dns_db_create(mctx, dbtype, dns_rootname, dns_dbtype_cache,
404 			       rdclass, 0, NULL, &view->cachedb);
405 	if (result != ISC_R_SUCCESS) {
406 		dns_view_detach(&view);
407 		return (result);
408 	}
409 
410 	*viewp = view;
411 	return (ISC_R_SUCCESS);
412 }
413 
414 
415 isc_result_t
dns_client_create(isc_mem_t * mctx,isc_appctx_t * actx,isc_taskmgr_t * taskmgr,isc_socketmgr_t * socketmgr,isc_timermgr_t * timermgr,unsigned int options,dns_client_t ** clientp,const isc_sockaddr_t * localaddr4,const isc_sockaddr_t * localaddr6)416 dns_client_create(isc_mem_t *mctx, isc_appctx_t *actx, isc_taskmgr_t *taskmgr,
417 		  isc_socketmgr_t *socketmgr, isc_timermgr_t *timermgr,
418 		  unsigned int options, dns_client_t **clientp,
419 		  const isc_sockaddr_t *localaddr4,
420 		  const isc_sockaddr_t *localaddr6) {
421 	isc_result_t result;
422 	dns_client_t *client;
423 	dns_dispatchmgr_t *dispatchmgr = NULL;
424 	dns_dispatch_t *dispatchv4 = NULL;
425 	dns_dispatch_t *dispatchv6 = NULL;
426 	dns_view_t *view = NULL;
427 
428 	REQUIRE(mctx != NULL);
429 	REQUIRE(taskmgr != NULL);
430 	REQUIRE(timermgr != NULL);
431 	REQUIRE(socketmgr != NULL);
432 	REQUIRE(clientp != NULL && *clientp == NULL);
433 
434 	client = isc_mem_get(mctx, sizeof(*client));
435 
436 	isc_mutex_init(&client->lock);
437 
438 	client->actx = actx;
439 	client->taskmgr = taskmgr;
440 	client->socketmgr = socketmgr;
441 	client->timermgr = timermgr;
442 
443 	client->task = NULL;
444 	result = isc_task_create(client->taskmgr, 0, &client->task);
445 	if (result != ISC_R_SUCCESS) {
446 		goto cleanup_lock;
447 	}
448 
449 	result = dns_dispatchmgr_create(mctx, &dispatchmgr);
450 	if (result != ISC_R_SUCCESS) {
451 		goto cleanup_task;
452 	}
453 	client->dispatchmgr = dispatchmgr;
454 	(void)setsourceports(mctx, dispatchmgr);
455 
456 	/*
457 	 * If only one address family is specified, use it.
458 	 * If neither family is specified, or if both are, use both.
459 	 */
460 	client->dispatchv4 = NULL;
461 	if (localaddr4 != NULL || localaddr6 == NULL) {
462 		result = getudpdispatch(AF_INET, dispatchmgr, socketmgr,
463 					taskmgr, true, &dispatchv4, localaddr4);
464 		if (result == ISC_R_SUCCESS) {
465 			client->dispatchv4 = dispatchv4;
466 		}
467 	}
468 
469 	client->dispatchv6 = NULL;
470 	if (localaddr6 != NULL || localaddr4 == NULL) {
471 		result = getudpdispatch(AF_INET6, dispatchmgr, socketmgr,
472 					taskmgr, true, &dispatchv6, localaddr6);
473 		if (result == ISC_R_SUCCESS) {
474 			client->dispatchv6 = dispatchv6;
475 		}
476 	}
477 
478 	/* We need at least one of the dispatchers */
479 	if (dispatchv4 == NULL && dispatchv6 == NULL) {
480 		INSIST(result != ISC_R_SUCCESS);
481 		goto cleanup_dispatchmgr;
482 	}
483 
484 	isc_refcount_init(&client->references, 1);
485 
486 	/* Create the default view for class IN */
487 	result = createview(mctx, dns_rdataclass_in, options, taskmgr,
488 			    RESOLVER_NTASKS, socketmgr, timermgr, dispatchmgr,
489 			    dispatchv4, dispatchv6, &view);
490 	if (result != ISC_R_SUCCESS) {
491 		goto cleanup_references;
492 	}
493 
494 	ISC_LIST_INIT(client->viewlist);
495 	ISC_LIST_APPEND(client->viewlist, view, link);
496 
497 	dns_view_freeze(view); /* too early? */
498 
499 	ISC_LIST_INIT(client->resctxs);
500 	ISC_LIST_INIT(client->reqctxs);
501 	ISC_LIST_INIT(client->updatectxs);
502 
503 	client->mctx = NULL;
504 	isc_mem_attach(mctx, &client->mctx);
505 
506 	client->update_timeout = DEF_UPDATE_TIMEOUT;
507 	client->update_udptimeout = DEF_UPDATE_UDPTIMEOUT;
508 	client->update_udpretries = DEF_UPDATE_UDPRETRIES;
509 	client->find_timeout = DEF_FIND_TIMEOUT;
510 	client->find_udpretries = DEF_FIND_UDPRETRIES;
511 	client->attributes = 0;
512 
513 	client->magic = DNS_CLIENT_MAGIC;
514 
515 	*clientp = client;
516 
517 	return (ISC_R_SUCCESS);
518 
519 cleanup_references:
520 	isc_refcount_decrementz(&client->references);
521 	isc_refcount_destroy(&client->references);
522 cleanup_dispatchmgr:
523 	if (dispatchv4 != NULL) {
524 		dns_dispatch_detach(&dispatchv4);
525 	}
526 	if (dispatchv6 != NULL) {
527 		dns_dispatch_detach(&dispatchv6);
528 	}
529 	dns_dispatchmgr_destroy(&dispatchmgr);
530 cleanup_task:
531 	isc_task_detach(&client->task);
532 cleanup_lock:
533 	isc_mutex_destroy(&client->lock);
534 	isc_mem_put(mctx, client, sizeof(*client));
535 
536 	return (result);
537 }
538 
539 static void
destroyclient(dns_client_t * client)540 destroyclient(dns_client_t *client) {
541 	dns_view_t *view;
542 
543 	isc_refcount_destroy(&client->references);
544 
545 	while ((view = ISC_LIST_HEAD(client->viewlist)) != NULL) {
546 		ISC_LIST_UNLINK(client->viewlist, view, link);
547 		dns_view_detach(&view);
548 	}
549 
550 	if (client->dispatchv4 != NULL) {
551 		dns_dispatch_detach(&client->dispatchv4);
552 	}
553 	if (client->dispatchv6 != NULL) {
554 		dns_dispatch_detach(&client->dispatchv6);
555 	}
556 
557 	dns_dispatchmgr_destroy(&client->dispatchmgr);
558 
559 	isc_task_detach(&client->task);
560 	client->magic = 0;
561 
562 	isc_mem_putanddetach(&client->mctx, client, sizeof(*client));
563 }
564 
565 void
dns_client_destroy(dns_client_t ** clientp)566 dns_client_destroy(dns_client_t **clientp) {
567 	dns_client_t *client;
568 
569 	REQUIRE(clientp != NULL);
570 	client = *clientp;
571 	*clientp = NULL;
572 	REQUIRE(DNS_CLIENT_VALID(client));
573 
574 	if (isc_refcount_decrement(&client->references) == 1) {
575 		destroyclient(client);
576 	}
577 }
578 
579 isc_result_t
dns_client_setservers(dns_client_t * client,dns_rdataclass_t rdclass,const dns_name_t * name_space,isc_sockaddrlist_t * addrs)580 dns_client_setservers(dns_client_t *client, dns_rdataclass_t rdclass,
581 		      const dns_name_t *name_space, isc_sockaddrlist_t *addrs) {
582 	isc_result_t result;
583 	dns_view_t *view = NULL;
584 
585 	REQUIRE(DNS_CLIENT_VALID(client));
586 	REQUIRE(addrs != NULL);
587 
588 	if (name_space == NULL) {
589 		name_space = dns_rootname;
590 	}
591 
592 	LOCK(&client->lock);
593 	result = dns_viewlist_find(&client->viewlist, DNS_CLIENTVIEW_NAME,
594 				   rdclass, &view);
595 	if (result != ISC_R_SUCCESS) {
596 		UNLOCK(&client->lock);
597 		return (result);
598 	}
599 	UNLOCK(&client->lock);
600 
601 	result = dns_fwdtable_add(view->fwdtable, name_space, addrs,
602 				  dns_fwdpolicy_only);
603 
604 	dns_view_detach(&view);
605 
606 	return (result);
607 }
608 
609 isc_result_t
dns_client_clearservers(dns_client_t * client,dns_rdataclass_t rdclass,const dns_name_t * name_space)610 dns_client_clearservers(dns_client_t *client, dns_rdataclass_t rdclass,
611 			const dns_name_t *name_space) {
612 	isc_result_t result;
613 	dns_view_t *view = NULL;
614 
615 	REQUIRE(DNS_CLIENT_VALID(client));
616 
617 	if (name_space == NULL) {
618 		name_space = dns_rootname;
619 	}
620 
621 	LOCK(&client->lock);
622 	result = dns_viewlist_find(&client->viewlist, DNS_CLIENTVIEW_NAME,
623 				   rdclass, &view);
624 	if (result != ISC_R_SUCCESS) {
625 		UNLOCK(&client->lock);
626 		return (result);
627 	}
628 	UNLOCK(&client->lock);
629 
630 	result = dns_fwdtable_delete(view->fwdtable, name_space);
631 
632 	dns_view_detach(&view);
633 
634 	return (result);
635 }
636 
637 static isc_result_t
getrdataset(isc_mem_t * mctx,dns_rdataset_t ** rdatasetp)638 getrdataset(isc_mem_t *mctx, dns_rdataset_t **rdatasetp) {
639 	dns_rdataset_t *rdataset;
640 
641 	REQUIRE(mctx != NULL);
642 	REQUIRE(rdatasetp != NULL && *rdatasetp == NULL);
643 
644 	rdataset = isc_mem_get(mctx, sizeof(*rdataset));
645 
646 	dns_rdataset_init(rdataset);
647 
648 	*rdatasetp = rdataset;
649 
650 	return (ISC_R_SUCCESS);
651 }
652 
653 static void
putrdataset(isc_mem_t * mctx,dns_rdataset_t ** rdatasetp)654 putrdataset(isc_mem_t *mctx, dns_rdataset_t **rdatasetp) {
655 	dns_rdataset_t *rdataset;
656 
657 	REQUIRE(rdatasetp != NULL);
658 	rdataset = *rdatasetp;
659 	*rdatasetp = NULL;
660 	REQUIRE(rdataset != NULL);
661 
662 	if (dns_rdataset_isassociated(rdataset)) {
663 		dns_rdataset_disassociate(rdataset);
664 	}
665 
666 	isc_mem_put(mctx, rdataset, sizeof(*rdataset));
667 }
668 
669 static void
fetch_done(isc_task_t * task,isc_event_t * event)670 fetch_done(isc_task_t *task, isc_event_t *event) {
671 	resctx_t *rctx = event->ev_arg;
672 	dns_fetchevent_t *fevent;
673 
674 	REQUIRE(event->ev_type == DNS_EVENT_FETCHDONE);
675 	REQUIRE(RCTX_VALID(rctx));
676 	REQUIRE(rctx->task == task);
677 	fevent = (dns_fetchevent_t *)event;
678 
679 	client_resfind(rctx, fevent);
680 }
681 
682 static isc_result_t
start_fetch(resctx_t * rctx)683 start_fetch(resctx_t *rctx) {
684 	isc_result_t result;
685 	int fopts = 0;
686 
687 	/*
688 	 * The caller must be holding the rctx's lock.
689 	 */
690 
691 	REQUIRE(rctx->fetch == NULL);
692 
693 	if (!rctx->want_cdflag) {
694 		fopts |= DNS_FETCHOPT_NOCDFLAG;
695 	}
696 	if (!rctx->want_validation) {
697 		fopts |= DNS_FETCHOPT_NOVALIDATE;
698 	}
699 	if (rctx->want_tcp) {
700 		fopts |= DNS_FETCHOPT_TCP;
701 	}
702 
703 	result = dns_resolver_createfetch(
704 		rctx->view->resolver, dns_fixedname_name(&rctx->name),
705 		rctx->type, NULL, NULL, NULL, NULL, 0, fopts, 0, NULL,
706 		rctx->task, fetch_done, rctx, rctx->rdataset, rctx->sigrdataset,
707 		&rctx->fetch);
708 
709 	return (result);
710 }
711 
712 static isc_result_t
view_find(resctx_t * rctx,dns_db_t ** dbp,dns_dbnode_t ** nodep,dns_name_t * foundname)713 view_find(resctx_t *rctx, dns_db_t **dbp, dns_dbnode_t **nodep,
714 	  dns_name_t *foundname) {
715 	isc_result_t result;
716 	dns_name_t *name = dns_fixedname_name(&rctx->name);
717 	dns_rdatatype_t type;
718 
719 	if (rctx->type == dns_rdatatype_rrsig) {
720 		type = dns_rdatatype_any;
721 	} else {
722 		type = rctx->type;
723 	}
724 
725 	result = dns_view_find(rctx->view, name, type, 0, 0, false, false, dbp,
726 			       nodep, foundname, rctx->rdataset,
727 			       rctx->sigrdataset);
728 
729 	return (result);
730 }
731 
732 static void
client_resfind(resctx_t * rctx,dns_fetchevent_t * event)733 client_resfind(resctx_t *rctx, dns_fetchevent_t *event) {
734 	isc_mem_t *mctx;
735 	isc_result_t tresult, result = ISC_R_SUCCESS;
736 	isc_result_t vresult = ISC_R_SUCCESS;
737 	bool want_restart;
738 	bool send_event = false;
739 	dns_name_t *name, *prefix;
740 	dns_fixedname_t foundname, fixed;
741 	dns_rdataset_t *trdataset;
742 	dns_rdata_t rdata = DNS_RDATA_INIT;
743 	unsigned int nlabels;
744 	int order;
745 	dns_namereln_t namereln;
746 	dns_rdata_cname_t cname;
747 	dns_rdata_dname_t dname;
748 
749 	REQUIRE(RCTX_VALID(rctx));
750 
751 	LOCK(&rctx->lock);
752 
753 	mctx = rctx->view->mctx;
754 
755 	name = dns_fixedname_name(&rctx->name);
756 
757 	do {
758 		dns_name_t *fname = NULL;
759 		dns_name_t *ansname = NULL;
760 		dns_db_t *db = NULL;
761 		dns_dbnode_t *node = NULL;
762 
763 		rctx->restarts++;
764 		want_restart = false;
765 
766 		if (event == NULL && !rctx->canceled) {
767 			fname = dns_fixedname_initname(&foundname);
768 			INSIST(!dns_rdataset_isassociated(rctx->rdataset));
769 			INSIST(rctx->sigrdataset == NULL ||
770 			       !dns_rdataset_isassociated(rctx->sigrdataset));
771 			result = view_find(rctx, &db, &node, fname);
772 			if (result == ISC_R_NOTFOUND) {
773 				/*
774 				 * We don't know anything about the name.
775 				 * Launch a fetch.
776 				 */
777 				if (node != NULL) {
778 					INSIST(db != NULL);
779 					dns_db_detachnode(db, &node);
780 				}
781 				if (db != NULL) {
782 					dns_db_detach(&db);
783 				}
784 				result = start_fetch(rctx);
785 				if (result != ISC_R_SUCCESS) {
786 					putrdataset(mctx, &rctx->rdataset);
787 					if (rctx->sigrdataset != NULL) {
788 						putrdataset(mctx,
789 							    &rctx->sigrdataset);
790 					}
791 					send_event = true;
792 				}
793 				goto done;
794 			}
795 		} else {
796 			INSIST(event != NULL);
797 			INSIST(event->fetch == rctx->fetch);
798 			dns_resolver_destroyfetch(&rctx->fetch);
799 			db = event->db;
800 			node = event->node;
801 			result = event->result;
802 			vresult = event->vresult;
803 			fname = dns_fixedname_name(&event->foundname);
804 			INSIST(event->rdataset == rctx->rdataset);
805 			INSIST(event->sigrdataset == rctx->sigrdataset);
806 		}
807 
808 		/*
809 		 * If we've been canceled, forget about the result.
810 		 */
811 		if (rctx->canceled) {
812 			result = ISC_R_CANCELED;
813 		} else {
814 			/*
815 			 * Otherwise, get some resource for copying the
816 			 * result.
817 			 */
818 			dns_name_t *aname = dns_fixedname_name(&rctx->name);
819 
820 			ansname = isc_mem_get(mctx, sizeof(*ansname));
821 			dns_name_init(ansname, NULL);
822 
823 			dns_name_dup(aname, mctx, ansname);
824 		}
825 
826 		switch (result) {
827 		case ISC_R_SUCCESS:
828 			send_event = true;
829 			/*
830 			 * This case is handled in the main line below.
831 			 */
832 			break;
833 		case DNS_R_CNAME:
834 			/*
835 			 * Add the CNAME to the answer list.
836 			 */
837 			trdataset = rctx->rdataset;
838 			ISC_LIST_APPEND(ansname->list, rctx->rdataset, link);
839 			rctx->rdataset = NULL;
840 			if (rctx->sigrdataset != NULL) {
841 				ISC_LIST_APPEND(ansname->list,
842 						rctx->sigrdataset, link);
843 				rctx->sigrdataset = NULL;
844 			}
845 			ISC_LIST_APPEND(rctx->namelist, ansname, link);
846 			ansname = NULL;
847 
848 			/*
849 			 * Copy the CNAME's target into the lookup's
850 			 * query name and start over.
851 			 */
852 			tresult = dns_rdataset_first(trdataset);
853 			if (tresult != ISC_R_SUCCESS) {
854 				goto done;
855 			}
856 			dns_rdataset_current(trdataset, &rdata);
857 			tresult = dns_rdata_tostruct(&rdata, &cname, NULL);
858 			dns_rdata_reset(&rdata);
859 			if (tresult != ISC_R_SUCCESS) {
860 				goto done;
861 			}
862 			dns_name_copynf(&cname.cname, name);
863 			dns_rdata_freestruct(&cname);
864 			want_restart = true;
865 			goto done;
866 		case DNS_R_DNAME:
867 			/*
868 			 * Add the DNAME to the answer list.
869 			 */
870 			trdataset = rctx->rdataset;
871 			ISC_LIST_APPEND(ansname->list, rctx->rdataset, link);
872 			rctx->rdataset = NULL;
873 			if (rctx->sigrdataset != NULL) {
874 				ISC_LIST_APPEND(ansname->list,
875 						rctx->sigrdataset, link);
876 				rctx->sigrdataset = NULL;
877 			}
878 			ISC_LIST_APPEND(rctx->namelist, ansname, link);
879 			ansname = NULL;
880 
881 			namereln = dns_name_fullcompare(name, fname, &order,
882 							&nlabels);
883 			INSIST(namereln == dns_namereln_subdomain);
884 			/*
885 			 * Get the target name of the DNAME.
886 			 */
887 			tresult = dns_rdataset_first(trdataset);
888 			if (tresult != ISC_R_SUCCESS) {
889 				result = tresult;
890 				goto done;
891 			}
892 			dns_rdataset_current(trdataset, &rdata);
893 			tresult = dns_rdata_tostruct(&rdata, &dname, NULL);
894 			dns_rdata_reset(&rdata);
895 			if (tresult != ISC_R_SUCCESS) {
896 				result = tresult;
897 				goto done;
898 			}
899 			/*
900 			 * Construct the new query name and start over.
901 			 */
902 			prefix = dns_fixedname_initname(&fixed);
903 			dns_name_split(name, nlabels, prefix, NULL);
904 			tresult = dns_name_concatenate(prefix, &dname.dname,
905 						       name, NULL);
906 			dns_rdata_freestruct(&dname);
907 			if (tresult == ISC_R_SUCCESS) {
908 				want_restart = true;
909 			} else {
910 				result = tresult;
911 			}
912 			goto done;
913 		case DNS_R_NCACHENXDOMAIN:
914 		case DNS_R_NCACHENXRRSET:
915 			ISC_LIST_APPEND(ansname->list, rctx->rdataset, link);
916 			ISC_LIST_APPEND(rctx->namelist, ansname, link);
917 			ansname = NULL;
918 			rctx->rdataset = NULL;
919 			/* What about sigrdataset? */
920 			if (rctx->sigrdataset != NULL) {
921 				putrdataset(mctx, &rctx->sigrdataset);
922 			}
923 			send_event = true;
924 			goto done;
925 		default:
926 			if (rctx->rdataset != NULL) {
927 				putrdataset(mctx, &rctx->rdataset);
928 			}
929 			if (rctx->sigrdataset != NULL) {
930 				putrdataset(mctx, &rctx->sigrdataset);
931 			}
932 			send_event = true;
933 			goto done;
934 		}
935 
936 		if (rctx->type == dns_rdatatype_any) {
937 			int n = 0;
938 			dns_rdatasetiter_t *rdsiter = NULL;
939 
940 			tresult = dns_db_allrdatasets(db, node, NULL, 0, 0,
941 						      &rdsiter);
942 			if (tresult != ISC_R_SUCCESS) {
943 				result = tresult;
944 				goto done;
945 			}
946 
947 			tresult = dns_rdatasetiter_first(rdsiter);
948 			while (tresult == ISC_R_SUCCESS) {
949 				dns_rdatasetiter_current(rdsiter,
950 							 rctx->rdataset);
951 				if (rctx->rdataset->type != 0) {
952 					ISC_LIST_APPEND(ansname->list,
953 							rctx->rdataset, link);
954 					n++;
955 					rctx->rdataset = NULL;
956 				} else {
957 					/*
958 					 * We're not interested in this
959 					 * rdataset.
960 					 */
961 					dns_rdataset_disassociate(
962 						rctx->rdataset);
963 				}
964 				tresult = dns_rdatasetiter_next(rdsiter);
965 
966 				if (tresult == ISC_R_SUCCESS &&
967 				    rctx->rdataset == NULL)
968 				{
969 					tresult = getrdataset(mctx,
970 							      &rctx->rdataset);
971 					if (tresult != ISC_R_SUCCESS) {
972 						result = tresult;
973 						POST(result);
974 						break;
975 					}
976 				}
977 			}
978 			if (rctx->rdataset != NULL) {
979 				putrdataset(mctx, &rctx->rdataset);
980 			}
981 			if (rctx->sigrdataset != NULL) {
982 				putrdataset(mctx, &rctx->sigrdataset);
983 			}
984 			if (n == 0) {
985 				/*
986 				 * We didn't match any rdatasets (which means
987 				 * something went wrong in this
988 				 * implementation).
989 				 */
990 				result = DNS_R_SERVFAIL; /* better code? */
991 				POST(result);
992 			} else {
993 				ISC_LIST_APPEND(rctx->namelist, ansname, link);
994 				ansname = NULL;
995 			}
996 			dns_rdatasetiter_destroy(&rdsiter);
997 			if (tresult != ISC_R_NOMORE) {
998 				result = DNS_R_SERVFAIL; /* ditto */
999 			} else {
1000 				result = ISC_R_SUCCESS;
1001 			}
1002 			goto done;
1003 		} else {
1004 			/*
1005 			 * This is the "normal" case -- an ordinary question
1006 			 * to which we've got the answer.
1007 			 */
1008 			ISC_LIST_APPEND(ansname->list, rctx->rdataset, link);
1009 			rctx->rdataset = NULL;
1010 			if (rctx->sigrdataset != NULL) {
1011 				ISC_LIST_APPEND(ansname->list,
1012 						rctx->sigrdataset, link);
1013 				rctx->sigrdataset = NULL;
1014 			}
1015 			ISC_LIST_APPEND(rctx->namelist, ansname, link);
1016 			ansname = NULL;
1017 		}
1018 
1019 	done:
1020 		/*
1021 		 * Free temporary resources
1022 		 */
1023 		if (ansname != NULL) {
1024 			dns_rdataset_t *rdataset;
1025 
1026 			while ((rdataset = ISC_LIST_HEAD(ansname->list)) !=
1027 			       NULL)
1028 			{
1029 				ISC_LIST_UNLINK(ansname->list, rdataset, link);
1030 				putrdataset(mctx, &rdataset);
1031 			}
1032 			dns_name_free(ansname, mctx);
1033 			isc_mem_put(mctx, ansname, sizeof(*ansname));
1034 		}
1035 
1036 		if (node != NULL) {
1037 			dns_db_detachnode(db, &node);
1038 		}
1039 		if (db != NULL) {
1040 			dns_db_detach(&db);
1041 		}
1042 		if (event != NULL) {
1043 			isc_event_free(ISC_EVENT_PTR(&event));
1044 		}
1045 
1046 		/*
1047 		 * Limit the number of restarts.
1048 		 */
1049 		if (want_restart && rctx->restarts == MAX_RESTARTS) {
1050 			want_restart = false;
1051 			result = ISC_R_QUOTA;
1052 			send_event = true;
1053 		}
1054 
1055 		/*
1056 		 * Prepare further find with new resources
1057 		 */
1058 		if (want_restart) {
1059 			INSIST(rctx->rdataset == NULL &&
1060 			       rctx->sigrdataset == NULL);
1061 
1062 			result = getrdataset(mctx, &rctx->rdataset);
1063 			if (result == ISC_R_SUCCESS && rctx->want_dnssec) {
1064 				result = getrdataset(mctx, &rctx->sigrdataset);
1065 				if (result != ISC_R_SUCCESS) {
1066 					putrdataset(mctx, &rctx->rdataset);
1067 				}
1068 			}
1069 
1070 			if (result != ISC_R_SUCCESS) {
1071 				want_restart = false;
1072 				send_event = true;
1073 			}
1074 		}
1075 	} while (want_restart);
1076 
1077 	if (send_event) {
1078 		isc_task_t *task;
1079 
1080 		while ((name = ISC_LIST_HEAD(rctx->namelist)) != NULL) {
1081 			ISC_LIST_UNLINK(rctx->namelist, name, link);
1082 			ISC_LIST_APPEND(rctx->event->answerlist, name, link);
1083 		}
1084 
1085 		rctx->event->result = result;
1086 		rctx->event->vresult = vresult;
1087 		task = rctx->event->ev_sender;
1088 		rctx->event->ev_sender = rctx;
1089 		isc_task_sendanddetach(&task, ISC_EVENT_PTR(&rctx->event));
1090 	}
1091 
1092 	UNLOCK(&rctx->lock);
1093 }
1094 
1095 static void
suspend(isc_task_t * task,isc_event_t * event)1096 suspend(isc_task_t *task, isc_event_t *event) {
1097 	isc_appctx_t *actx = event->ev_arg;
1098 
1099 	UNUSED(task);
1100 
1101 	isc_app_ctxsuspend(actx);
1102 	isc_event_free(&event);
1103 }
1104 
1105 static void
resolve_done(isc_task_t * task,isc_event_t * event)1106 resolve_done(isc_task_t *task, isc_event_t *event) {
1107 	resarg_t *resarg = event->ev_arg;
1108 	dns_clientresevent_t *rev = (dns_clientresevent_t *)event;
1109 	dns_name_t *name;
1110 	isc_result_t result;
1111 
1112 	UNUSED(task);
1113 
1114 	LOCK(&resarg->lock);
1115 
1116 	resarg->result = rev->result;
1117 	resarg->vresult = rev->vresult;
1118 	while ((name = ISC_LIST_HEAD(rev->answerlist)) != NULL) {
1119 		ISC_LIST_UNLINK(rev->answerlist, name, link);
1120 		ISC_LIST_APPEND(*resarg->namelist, name, link);
1121 	}
1122 
1123 	dns_client_destroyrestrans(&resarg->trans);
1124 	isc_event_free(&event);
1125 
1126 	if (!resarg->canceled) {
1127 		UNLOCK(&resarg->lock);
1128 
1129 		/*
1130 		 * We may or may not be running.  isc__appctx_onrun will
1131 		 * fail if we are currently running otherwise we post a
1132 		 * action to call isc_app_ctxsuspend when we do start
1133 		 * running.
1134 		 */
1135 		result = isc_app_ctxonrun(resarg->actx, resarg->client->mctx,
1136 					  task, suspend, resarg->actx);
1137 		if (result == ISC_R_ALREADYRUNNING) {
1138 			isc_app_ctxsuspend(resarg->actx);
1139 		}
1140 	} else {
1141 		/*
1142 		 * We have already exited from the loop (due to some
1143 		 * unexpected event).  Just clean the arg up.
1144 		 */
1145 		UNLOCK(&resarg->lock);
1146 		isc_mutex_destroy(&resarg->lock);
1147 		isc_mem_put(resarg->client->mctx, resarg, sizeof(*resarg));
1148 	}
1149 }
1150 
1151 isc_result_t
dns_client_resolve(dns_client_t * client,const dns_name_t * name,dns_rdataclass_t rdclass,dns_rdatatype_t type,unsigned int options,dns_namelist_t * namelist)1152 dns_client_resolve(dns_client_t *client, const dns_name_t *name,
1153 		   dns_rdataclass_t rdclass, dns_rdatatype_t type,
1154 		   unsigned int options, dns_namelist_t *namelist) {
1155 	isc_result_t result;
1156 	isc_appctx_t *actx;
1157 	resarg_t *resarg;
1158 
1159 	REQUIRE(DNS_CLIENT_VALID(client));
1160 	REQUIRE(namelist != NULL && ISC_LIST_EMPTY(*namelist));
1161 
1162 	if ((client->attributes & DNS_CLIENTATTR_OWNCTX) == 0 &&
1163 	    (options & DNS_CLIENTRESOPT_ALLOWRUN) == 0)
1164 	{
1165 		/*
1166 		 * If the client is run under application's control, we need
1167 		 * to create a new running (sub)environment for this
1168 		 * particular resolution.
1169 		 */
1170 		return (ISC_R_NOTIMPLEMENTED); /* XXXTBD */
1171 	} else {
1172 		actx = client->actx;
1173 	}
1174 
1175 	resarg = isc_mem_get(client->mctx, sizeof(*resarg));
1176 
1177 	isc_mutex_init(&resarg->lock);
1178 
1179 	resarg->actx = actx;
1180 	resarg->client = client;
1181 	resarg->result = DNS_R_SERVFAIL;
1182 	resarg->namelist = namelist;
1183 	resarg->trans = NULL;
1184 	resarg->canceled = false;
1185 	result = dns_client_startresolve(client, name, rdclass, type, options,
1186 					 client->task, resolve_done, resarg,
1187 					 &resarg->trans);
1188 	if (result != ISC_R_SUCCESS) {
1189 		isc_mutex_destroy(&resarg->lock);
1190 		isc_mem_put(client->mctx, resarg, sizeof(*resarg));
1191 		return (result);
1192 	}
1193 
1194 	/*
1195 	 * Start internal event loop.  It blocks until the entire process
1196 	 * is completed.
1197 	 */
1198 	result = isc_app_ctxrun(actx);
1199 
1200 	LOCK(&resarg->lock);
1201 	if (result == ISC_R_SUCCESS || result == ISC_R_SUSPEND) {
1202 		result = resarg->result;
1203 	}
1204 	if (result != ISC_R_SUCCESS && resarg->vresult != ISC_R_SUCCESS) {
1205 		/*
1206 		 * If this lookup failed due to some error in DNSSEC
1207 		 * validation, return the validation error code.
1208 		 * XXX: or should we pass the validation result separately?
1209 		 */
1210 		result = resarg->vresult;
1211 	}
1212 	if (resarg->trans != NULL) {
1213 		/*
1214 		 * Unusual termination (perhaps due to signal).  We need some
1215 		 * tricky cleanup process.
1216 		 */
1217 		resarg->canceled = true;
1218 		dns_client_cancelresolve(resarg->trans);
1219 
1220 		UNLOCK(&resarg->lock);
1221 
1222 		/* resarg will be freed in the event handler. */
1223 	} else {
1224 		UNLOCK(&resarg->lock);
1225 
1226 		isc_mutex_destroy(&resarg->lock);
1227 		isc_mem_put(client->mctx, resarg, sizeof(*resarg));
1228 	}
1229 
1230 	return (result);
1231 }
1232 
1233 isc_result_t
dns_client_startresolve(dns_client_t * client,const dns_name_t * name,dns_rdataclass_t rdclass,dns_rdatatype_t type,unsigned int options,isc_task_t * task,isc_taskaction_t action,void * arg,dns_clientrestrans_t ** transp)1234 dns_client_startresolve(dns_client_t *client, const dns_name_t *name,
1235 			dns_rdataclass_t rdclass, dns_rdatatype_t type,
1236 			unsigned int options, isc_task_t *task,
1237 			isc_taskaction_t action, void *arg,
1238 			dns_clientrestrans_t **transp) {
1239 	dns_view_t *view = NULL;
1240 	dns_clientresevent_t *event = NULL;
1241 	resctx_t *rctx = NULL;
1242 	isc_task_t *tclone = NULL;
1243 	isc_mem_t *mctx;
1244 	isc_result_t result;
1245 	dns_rdataset_t *rdataset, *sigrdataset;
1246 	bool want_dnssec, want_validation, want_cdflag, want_tcp;
1247 
1248 	REQUIRE(DNS_CLIENT_VALID(client));
1249 	REQUIRE(transp != NULL && *transp == NULL);
1250 
1251 	LOCK(&client->lock);
1252 	result = dns_viewlist_find(&client->viewlist, DNS_CLIENTVIEW_NAME,
1253 				   rdclass, &view);
1254 	UNLOCK(&client->lock);
1255 	if (result != ISC_R_SUCCESS) {
1256 		return (result);
1257 	}
1258 
1259 	mctx = client->mctx;
1260 	rdataset = NULL;
1261 	sigrdataset = NULL;
1262 	want_dnssec = ((options & DNS_CLIENTRESOPT_NODNSSEC) == 0);
1263 	want_validation = ((options & DNS_CLIENTRESOPT_NOVALIDATE) == 0);
1264 	want_cdflag = ((options & DNS_CLIENTRESOPT_NOCDFLAG) == 0);
1265 	want_tcp = ((options & DNS_CLIENTRESOPT_TCP) != 0);
1266 
1267 	/*
1268 	 * Prepare some intermediate resources
1269 	 */
1270 	tclone = NULL;
1271 	isc_task_attach(task, &tclone);
1272 	event = (dns_clientresevent_t *)isc_event_allocate(
1273 		mctx, tclone, DNS_EVENT_CLIENTRESDONE, action, arg,
1274 		sizeof(*event));
1275 	event->result = DNS_R_SERVFAIL;
1276 	ISC_LIST_INIT(event->answerlist);
1277 
1278 	rctx = isc_mem_get(mctx, sizeof(*rctx));
1279 	isc_mutex_init(&rctx->lock);
1280 
1281 	result = getrdataset(mctx, &rdataset);
1282 	if (result != ISC_R_SUCCESS) {
1283 		goto cleanup;
1284 	}
1285 	rctx->rdataset = rdataset;
1286 
1287 	if (want_dnssec) {
1288 		result = getrdataset(mctx, &sigrdataset);
1289 		if (result != ISC_R_SUCCESS) {
1290 			goto cleanup;
1291 		}
1292 	}
1293 	rctx->sigrdataset = sigrdataset;
1294 
1295 	dns_fixedname_init(&rctx->name);
1296 	dns_name_copynf(name, dns_fixedname_name(&rctx->name));
1297 
1298 	rctx->client = client;
1299 	ISC_LINK_INIT(rctx, link);
1300 	rctx->canceled = false;
1301 	rctx->task = client->task;
1302 	rctx->type = type;
1303 	rctx->view = view;
1304 	rctx->restarts = 0;
1305 	rctx->fetch = NULL;
1306 	rctx->want_dnssec = want_dnssec;
1307 	rctx->want_validation = want_validation;
1308 	rctx->want_cdflag = want_cdflag;
1309 	rctx->want_tcp = want_tcp;
1310 	ISC_LIST_INIT(rctx->namelist);
1311 	rctx->event = event;
1312 
1313 	rctx->magic = RCTX_MAGIC;
1314 	isc_refcount_increment(&client->references);
1315 
1316 	LOCK(&client->lock);
1317 	ISC_LIST_APPEND(client->resctxs, rctx, link);
1318 	UNLOCK(&client->lock);
1319 
1320 	*transp = (dns_clientrestrans_t *)rctx;
1321 	client_resfind(rctx, NULL);
1322 
1323 	return (ISC_R_SUCCESS);
1324 
1325 cleanup:
1326 	if (rdataset != NULL) {
1327 		putrdataset(client->mctx, &rdataset);
1328 	}
1329 	if (sigrdataset != NULL) {
1330 		putrdataset(client->mctx, &sigrdataset);
1331 	}
1332 	isc_mutex_destroy(&rctx->lock);
1333 	isc_mem_put(mctx, rctx, sizeof(*rctx));
1334 	isc_event_free(ISC_EVENT_PTR(&event));
1335 	isc_task_detach(&tclone);
1336 	dns_view_detach(&view);
1337 
1338 	return (result);
1339 }
1340 
1341 void
dns_client_cancelresolve(dns_clientrestrans_t * trans)1342 dns_client_cancelresolve(dns_clientrestrans_t *trans) {
1343 	resctx_t *rctx;
1344 
1345 	REQUIRE(trans != NULL);
1346 	rctx = (resctx_t *)trans;
1347 	REQUIRE(RCTX_VALID(rctx));
1348 
1349 	LOCK(&rctx->lock);
1350 
1351 	if (!rctx->canceled) {
1352 		rctx->canceled = true;
1353 		if (rctx->fetch != NULL) {
1354 			dns_resolver_cancelfetch(rctx->fetch);
1355 		}
1356 	}
1357 
1358 	UNLOCK(&rctx->lock);
1359 }
1360 
1361 void
dns_client_freeresanswer(dns_client_t * client,dns_namelist_t * namelist)1362 dns_client_freeresanswer(dns_client_t *client, dns_namelist_t *namelist) {
1363 	dns_name_t *name;
1364 	dns_rdataset_t *rdataset;
1365 
1366 	REQUIRE(DNS_CLIENT_VALID(client));
1367 	REQUIRE(namelist != NULL);
1368 
1369 	while ((name = ISC_LIST_HEAD(*namelist)) != NULL) {
1370 		ISC_LIST_UNLINK(*namelist, name, link);
1371 		while ((rdataset = ISC_LIST_HEAD(name->list)) != NULL) {
1372 			ISC_LIST_UNLINK(name->list, rdataset, link);
1373 			putrdataset(client->mctx, &rdataset);
1374 		}
1375 		dns_name_free(name, client->mctx);
1376 		isc_mem_put(client->mctx, name, sizeof(*name));
1377 	}
1378 }
1379 
1380 void
dns_client_destroyrestrans(dns_clientrestrans_t ** transp)1381 dns_client_destroyrestrans(dns_clientrestrans_t **transp) {
1382 	resctx_t *rctx;
1383 	isc_mem_t *mctx;
1384 	dns_client_t *client;
1385 
1386 	REQUIRE(transp != NULL);
1387 	rctx = (resctx_t *)*transp;
1388 	*transp = NULL;
1389 	REQUIRE(RCTX_VALID(rctx));
1390 	REQUIRE(rctx->fetch == NULL);
1391 	REQUIRE(rctx->event == NULL);
1392 	client = rctx->client;
1393 	REQUIRE(DNS_CLIENT_VALID(client));
1394 
1395 	mctx = client->mctx;
1396 	dns_view_detach(&rctx->view);
1397 
1398 	/*
1399 	 * Wait for the lock in client_resfind to be released before
1400 	 * destroying the lock.
1401 	 */
1402 	LOCK(&rctx->lock);
1403 	UNLOCK(&rctx->lock);
1404 
1405 	LOCK(&client->lock);
1406 
1407 	INSIST(ISC_LINK_LINKED(rctx, link));
1408 	ISC_LIST_UNLINK(client->resctxs, rctx, link);
1409 
1410 	UNLOCK(&client->lock);
1411 
1412 	INSIST(ISC_LIST_EMPTY(rctx->namelist));
1413 
1414 	isc_mutex_destroy(&rctx->lock);
1415 	rctx->magic = 0;
1416 
1417 	isc_mem_put(mctx, rctx, sizeof(*rctx));
1418 
1419 	dns_client_destroy(&client);
1420 }
1421 
1422 isc_result_t
dns_client_addtrustedkey(dns_client_t * client,dns_rdataclass_t rdclass,dns_rdatatype_t rdtype,const dns_name_t * keyname,isc_buffer_t * databuf)1423 dns_client_addtrustedkey(dns_client_t *client, dns_rdataclass_t rdclass,
1424 			 dns_rdatatype_t rdtype, const dns_name_t *keyname,
1425 			 isc_buffer_t *databuf) {
1426 	isc_result_t result;
1427 	dns_view_t *view = NULL;
1428 	dns_keytable_t *secroots = NULL;
1429 	dns_name_t *name = NULL;
1430 	char rdatabuf[DST_KEY_MAXSIZE];
1431 	unsigned char digest[ISC_MAX_MD_SIZE];
1432 	dns_rdata_ds_t ds;
1433 	dns_decompress_t dctx;
1434 	dns_rdata_t rdata;
1435 	isc_buffer_t b;
1436 
1437 	REQUIRE(DNS_CLIENT_VALID(client));
1438 
1439 	LOCK(&client->lock);
1440 	result = dns_viewlist_find(&client->viewlist, DNS_CLIENTVIEW_NAME,
1441 				   rdclass, &view);
1442 	UNLOCK(&client->lock);
1443 	CHECK(result);
1444 
1445 	CHECK(dns_view_getsecroots(view, &secroots));
1446 
1447 	DE_CONST(keyname, name);
1448 
1449 	if (rdtype != dns_rdatatype_dnskey && rdtype != dns_rdatatype_ds) {
1450 		result = ISC_R_NOTIMPLEMENTED;
1451 		goto cleanup;
1452 	}
1453 
1454 	isc_buffer_init(&b, rdatabuf, sizeof(rdatabuf));
1455 	dns_decompress_init(&dctx, -1, DNS_DECOMPRESS_NONE);
1456 	dns_rdata_init(&rdata);
1457 	isc_buffer_setactive(databuf, isc_buffer_usedlength(databuf));
1458 	CHECK(dns_rdata_fromwire(&rdata, rdclass, rdtype, databuf, &dctx, 0,
1459 				 &b));
1460 	dns_decompress_invalidate(&dctx);
1461 
1462 	if (rdtype == dns_rdatatype_ds) {
1463 		CHECK(dns_rdata_tostruct(&rdata, &ds, NULL));
1464 	} else {
1465 		CHECK(dns_ds_fromkeyrdata(name, &rdata, DNS_DSDIGEST_SHA256,
1466 					  digest, &ds));
1467 	}
1468 
1469 	CHECK(dns_keytable_add(secroots, false, false, name, &ds));
1470 
1471 cleanup:
1472 	if (view != NULL) {
1473 		dns_view_detach(&view);
1474 	}
1475 	if (secroots != NULL) {
1476 		dns_keytable_detach(&secroots);
1477 	}
1478 	return (result);
1479 }
1480 
1481 /*%
1482  * Simple request routines
1483  */
1484 static void
request_done(isc_task_t * task,isc_event_t * event)1485 request_done(isc_task_t *task, isc_event_t *event) {
1486 	dns_requestevent_t *reqev = NULL;
1487 	dns_request_t *request;
1488 	isc_result_t result, eresult;
1489 	reqctx_t *ctx;
1490 
1491 	UNUSED(task);
1492 
1493 	REQUIRE(event->ev_type == DNS_EVENT_REQUESTDONE);
1494 	reqev = (dns_requestevent_t *)event;
1495 	request = reqev->request;
1496 	result = eresult = reqev->result;
1497 	ctx = reqev->ev_arg;
1498 	REQUIRE(REQCTX_VALID(ctx));
1499 
1500 	isc_event_free(&event);
1501 
1502 	LOCK(&ctx->lock);
1503 
1504 	if (eresult == ISC_R_SUCCESS) {
1505 		result = dns_request_getresponse(request, ctx->event->rmessage,
1506 						 ctx->parseoptions);
1507 	}
1508 
1509 	if (ctx->tsigkey != NULL) {
1510 		dns_tsigkey_detach(&ctx->tsigkey);
1511 	}
1512 
1513 	if (ctx->canceled) {
1514 		ctx->event->result = ISC_R_CANCELED;
1515 	} else {
1516 		ctx->event->result = result;
1517 	}
1518 	task = ctx->event->ev_sender;
1519 	ctx->event->ev_sender = ctx;
1520 	isc_task_sendanddetach(&task, ISC_EVENT_PTR(&ctx->event));
1521 
1522 	UNLOCK(&ctx->lock);
1523 }
1524 
1525 static void
localrequest_done(isc_task_t * task,isc_event_t * event)1526 localrequest_done(isc_task_t *task, isc_event_t *event) {
1527 	reqarg_t *reqarg = event->ev_arg;
1528 	dns_clientreqevent_t *rev = (dns_clientreqevent_t *)event;
1529 
1530 	UNUSED(task);
1531 
1532 	REQUIRE(event->ev_type == DNS_EVENT_CLIENTREQDONE);
1533 
1534 	LOCK(&reqarg->lock);
1535 
1536 	reqarg->result = rev->result;
1537 	dns_client_destroyreqtrans(&reqarg->trans);
1538 	isc_event_free(&event);
1539 
1540 	if (!reqarg->canceled) {
1541 		UNLOCK(&reqarg->lock);
1542 
1543 		/* Exit from the internal event loop */
1544 		isc_app_ctxsuspend(reqarg->actx);
1545 	} else {
1546 		/*
1547 		 * We have already exited from the loop (due to some
1548 		 * unexpected event).  Just clean the arg up.
1549 		 */
1550 		UNLOCK(&reqarg->lock);
1551 		isc_mutex_destroy(&reqarg->lock);
1552 		isc_mem_put(reqarg->client->mctx, reqarg, sizeof(*reqarg));
1553 	}
1554 }
1555 
1556 isc_result_t
dns_client_request(dns_client_t * client,dns_message_t * qmessage,dns_message_t * rmessage,const isc_sockaddr_t * server,unsigned int options,unsigned int parseoptions,dns_tsec_t * tsec,unsigned int timeout,unsigned int udptimeout,unsigned int udpretries)1557 dns_client_request(dns_client_t *client, dns_message_t *qmessage,
1558 		   dns_message_t *rmessage, const isc_sockaddr_t *server,
1559 		   unsigned int options, unsigned int parseoptions,
1560 		   dns_tsec_t *tsec, unsigned int timeout,
1561 		   unsigned int udptimeout, unsigned int udpretries) {
1562 	isc_appctx_t *actx;
1563 	reqarg_t *reqarg;
1564 	isc_result_t result;
1565 
1566 	REQUIRE(DNS_CLIENT_VALID(client));
1567 	REQUIRE(qmessage != NULL);
1568 	REQUIRE(rmessage != NULL);
1569 
1570 	if ((client->attributes & DNS_CLIENTATTR_OWNCTX) == 0 &&
1571 	    (options & DNS_CLIENTREQOPT_ALLOWRUN) == 0)
1572 	{
1573 		/*
1574 		 * If the client is run under application's control, we need
1575 		 * to create a new running (sub)environment for this
1576 		 * particular resolution.
1577 		 */
1578 		return (ISC_R_NOTIMPLEMENTED); /* XXXTBD */
1579 	} else {
1580 		actx = client->actx;
1581 	}
1582 
1583 	reqarg = isc_mem_get(client->mctx, sizeof(*reqarg));
1584 
1585 	isc_mutex_init(&reqarg->lock);
1586 
1587 	reqarg->actx = actx;
1588 	reqarg->client = client;
1589 	reqarg->trans = NULL;
1590 	reqarg->canceled = false;
1591 
1592 	result = dns_client_startrequest(
1593 		client, qmessage, rmessage, server, options, parseoptions, tsec,
1594 		timeout, udptimeout, udpretries, client->task,
1595 		localrequest_done, reqarg, &reqarg->trans);
1596 	if (result != ISC_R_SUCCESS) {
1597 		isc_mutex_destroy(&reqarg->lock);
1598 		isc_mem_put(client->mctx, reqarg, sizeof(*reqarg));
1599 		return (result);
1600 	}
1601 
1602 	/*
1603 	 * Start internal event loop.  It blocks until the entire process
1604 	 * is completed.
1605 	 */
1606 	result = isc_app_ctxrun(actx);
1607 
1608 	LOCK(&reqarg->lock);
1609 	if (result == ISC_R_SUCCESS || result == ISC_R_SUSPEND) {
1610 		result = reqarg->result;
1611 	}
1612 	if (reqarg->trans != NULL) {
1613 		/*
1614 		 * Unusual termination (perhaps due to signal).  We need some
1615 		 * tricky cleanup process.
1616 		 */
1617 		reqarg->canceled = true;
1618 		dns_client_cancelresolve(reqarg->trans);
1619 
1620 		UNLOCK(&reqarg->lock);
1621 
1622 		/* reqarg will be freed in the event handler. */
1623 	} else {
1624 		UNLOCK(&reqarg->lock);
1625 
1626 		isc_mutex_destroy(&reqarg->lock);
1627 		isc_mem_put(client->mctx, reqarg, sizeof(*reqarg));
1628 	}
1629 
1630 	return (result);
1631 }
1632 
1633 isc_result_t
dns_client_startrequest(dns_client_t * client,dns_message_t * qmessage,dns_message_t * rmessage,const isc_sockaddr_t * server,unsigned int options,unsigned int parseoptions,dns_tsec_t * tsec,unsigned int timeout,unsigned int udptimeout,unsigned int udpretries,isc_task_t * task,isc_taskaction_t action,void * arg,dns_clientreqtrans_t ** transp)1634 dns_client_startrequest(dns_client_t *client, dns_message_t *qmessage,
1635 			dns_message_t *rmessage, const isc_sockaddr_t *server,
1636 			unsigned int options, unsigned int parseoptions,
1637 			dns_tsec_t *tsec, unsigned int timeout,
1638 			unsigned int udptimeout, unsigned int udpretries,
1639 			isc_task_t *task, isc_taskaction_t action, void *arg,
1640 			dns_clientreqtrans_t **transp) {
1641 	isc_result_t result;
1642 	dns_view_t *view = NULL;
1643 	isc_task_t *tclone = NULL;
1644 	dns_clientreqevent_t *event = NULL;
1645 	reqctx_t *ctx = NULL;
1646 	dns_tsectype_t tsectype = dns_tsectype_none;
1647 	unsigned int reqoptions;
1648 
1649 	REQUIRE(DNS_CLIENT_VALID(client));
1650 	REQUIRE(qmessage != NULL);
1651 	REQUIRE(rmessage != NULL);
1652 	REQUIRE(transp != NULL && *transp == NULL);
1653 
1654 	if (tsec != NULL) {
1655 		tsectype = dns_tsec_gettype(tsec);
1656 		if (tsectype != dns_tsectype_tsig) {
1657 			return (ISC_R_NOTIMPLEMENTED); /* XXX */
1658 		}
1659 	}
1660 
1661 	LOCK(&client->lock);
1662 	result = dns_viewlist_find(&client->viewlist, DNS_CLIENTVIEW_NAME,
1663 				   qmessage->rdclass, &view);
1664 	UNLOCK(&client->lock);
1665 	if (result != ISC_R_SUCCESS) {
1666 		return (result);
1667 	}
1668 
1669 	reqoptions = 0;
1670 	if ((options & DNS_CLIENTREQOPT_TCP) != 0) {
1671 		reqoptions |= DNS_REQUESTOPT_TCP;
1672 	}
1673 
1674 	tclone = NULL;
1675 	isc_task_attach(task, &tclone);
1676 	event = (dns_clientreqevent_t *)isc_event_allocate(
1677 		client->mctx, tclone, DNS_EVENT_CLIENTREQDONE, action, arg,
1678 		sizeof(*event));
1679 
1680 	ctx = isc_mem_get(client->mctx, sizeof(*ctx));
1681 	isc_mutex_init(&ctx->lock);
1682 
1683 	ctx->client = client;
1684 	ISC_LINK_INIT(ctx, link);
1685 	ctx->parseoptions = parseoptions;
1686 	ctx->canceled = false;
1687 	ctx->event = event;
1688 	ctx->event->rmessage = rmessage;
1689 	ctx->tsigkey = NULL;
1690 	if (tsec != NULL) {
1691 		dns_tsec_getkey(tsec, &ctx->tsigkey);
1692 	}
1693 
1694 	ctx->magic = REQCTX_MAGIC;
1695 
1696 	LOCK(&client->lock);
1697 	ISC_LIST_APPEND(client->reqctxs, ctx, link);
1698 	isc_refcount_increment(&client->references);
1699 	UNLOCK(&client->lock);
1700 
1701 	ctx->request = NULL;
1702 	result = dns_request_createvia(view->requestmgr, qmessage, NULL, server,
1703 				       -1, reqoptions, ctx->tsigkey, timeout,
1704 				       udptimeout, udpretries, client->task,
1705 				       request_done, ctx, &ctx->request);
1706 	if (result == ISC_R_SUCCESS) {
1707 		dns_view_detach(&view);
1708 		*transp = (dns_clientreqtrans_t *)ctx;
1709 		return (ISC_R_SUCCESS);
1710 	}
1711 
1712 	isc_refcount_decrement1(&client->references);
1713 
1714 	LOCK(&client->lock);
1715 	ISC_LIST_UNLINK(client->reqctxs, ctx, link);
1716 	UNLOCK(&client->lock);
1717 	isc_mutex_destroy(&ctx->lock);
1718 	isc_mem_put(client->mctx, ctx, sizeof(*ctx));
1719 
1720 	isc_event_free(ISC_EVENT_PTR(&event));
1721 	isc_task_detach(&tclone);
1722 	dns_view_detach(&view);
1723 
1724 	return (result);
1725 }
1726 
1727 void
dns_client_cancelrequest(dns_clientreqtrans_t * trans)1728 dns_client_cancelrequest(dns_clientreqtrans_t *trans) {
1729 	reqctx_t *ctx;
1730 
1731 	REQUIRE(trans != NULL);
1732 	ctx = (reqctx_t *)trans;
1733 	REQUIRE(REQCTX_VALID(ctx));
1734 
1735 	LOCK(&ctx->lock);
1736 
1737 	if (!ctx->canceled) {
1738 		ctx->canceled = true;
1739 		if (ctx->request != NULL) {
1740 			dns_request_cancel(ctx->request);
1741 		}
1742 	}
1743 
1744 	UNLOCK(&ctx->lock);
1745 }
1746 
1747 void
dns_client_destroyreqtrans(dns_clientreqtrans_t ** transp)1748 dns_client_destroyreqtrans(dns_clientreqtrans_t **transp) {
1749 	reqctx_t *ctx;
1750 	isc_mem_t *mctx;
1751 	dns_client_t *client;
1752 
1753 	REQUIRE(transp != NULL);
1754 	ctx = (reqctx_t *)*transp;
1755 	*transp = NULL;
1756 	REQUIRE(REQCTX_VALID(ctx));
1757 	client = ctx->client;
1758 	REQUIRE(DNS_CLIENT_VALID(client));
1759 	REQUIRE(ctx->event == NULL);
1760 	REQUIRE(ctx->request != NULL);
1761 
1762 	dns_request_destroy(&ctx->request);
1763 	mctx = client->mctx;
1764 
1765 	LOCK(&client->lock);
1766 
1767 	INSIST(ISC_LINK_LINKED(ctx, link));
1768 	ISC_LIST_UNLINK(client->reqctxs, ctx, link);
1769 
1770 	UNLOCK(&client->lock);
1771 
1772 	isc_mutex_destroy(&ctx->lock);
1773 	ctx->magic = 0;
1774 
1775 	isc_mem_put(mctx, ctx, sizeof(*ctx));
1776 
1777 	dns_client_destroy(&client);
1778 }
1779 
1780 /*%
1781  * Dynamic update routines
1782  */
1783 static isc_result_t
rcode2result(dns_rcode_t rcode)1784 rcode2result(dns_rcode_t rcode) {
1785 	/* XXX: isn't there a similar function? */
1786 	switch (rcode) {
1787 	case dns_rcode_formerr:
1788 		return (DNS_R_FORMERR);
1789 	case dns_rcode_servfail:
1790 		return (DNS_R_SERVFAIL);
1791 	case dns_rcode_nxdomain:
1792 		return (DNS_R_NXDOMAIN);
1793 	case dns_rcode_notimp:
1794 		return (DNS_R_NOTIMP);
1795 	case dns_rcode_refused:
1796 		return (DNS_R_REFUSED);
1797 	case dns_rcode_yxdomain:
1798 		return (DNS_R_YXDOMAIN);
1799 	case dns_rcode_yxrrset:
1800 		return (DNS_R_YXRRSET);
1801 	case dns_rcode_nxrrset:
1802 		return (DNS_R_NXRRSET);
1803 	case dns_rcode_notauth:
1804 		return (DNS_R_NOTAUTH);
1805 	case dns_rcode_notzone:
1806 		return (DNS_R_NOTZONE);
1807 	case dns_rcode_badvers:
1808 		return (DNS_R_BADVERS);
1809 	}
1810 
1811 	return (ISC_R_FAILURE);
1812 }
1813 
1814 static void
update_sendevent(updatectx_t * uctx,isc_result_t result)1815 update_sendevent(updatectx_t *uctx, isc_result_t result) {
1816 	isc_task_t *task;
1817 
1818 	dns_message_detach(&uctx->updatemsg);
1819 	if (uctx->tsigkey != NULL) {
1820 		dns_tsigkey_detach(&uctx->tsigkey);
1821 	}
1822 	if (uctx->sig0key != NULL) {
1823 		dst_key_free(&uctx->sig0key);
1824 	}
1825 
1826 	if (uctx->canceled) {
1827 		uctx->event->result = ISC_R_CANCELED;
1828 	} else {
1829 		uctx->event->result = result;
1830 	}
1831 	uctx->event->state = uctx->state;
1832 	task = uctx->event->ev_sender;
1833 	uctx->event->ev_sender = uctx;
1834 	isc_task_sendanddetach(&task, ISC_EVENT_PTR(&uctx->event));
1835 }
1836 
1837 static void
update_done(isc_task_t * task,isc_event_t * event)1838 update_done(isc_task_t *task, isc_event_t *event) {
1839 	isc_result_t result;
1840 	dns_requestevent_t *reqev = NULL;
1841 	dns_request_t *request;
1842 	dns_message_t *answer = NULL;
1843 	updatectx_t *uctx = event->ev_arg;
1844 	dns_client_t *client;
1845 	unsigned int timeout, reqoptions;
1846 
1847 	UNUSED(task);
1848 
1849 	REQUIRE(event->ev_type == DNS_EVENT_REQUESTDONE);
1850 	reqev = (dns_requestevent_t *)event;
1851 	request = reqev->request;
1852 	REQUIRE(UCTX_VALID(uctx));
1853 	client = uctx->client;
1854 	REQUIRE(DNS_CLIENT_VALID(client));
1855 
1856 	result = reqev->result;
1857 	if (result != ISC_R_SUCCESS) {
1858 		goto out;
1859 	}
1860 
1861 	dns_message_create(client->mctx, DNS_MESSAGE_INTENTPARSE, &answer);
1862 	uctx->state = dns_clientupdatestate_done;
1863 	result = dns_request_getresponse(request, answer,
1864 					 DNS_MESSAGEPARSE_PRESERVEORDER);
1865 	if (result == ISC_R_SUCCESS && answer->rcode != dns_rcode_noerror) {
1866 		result = rcode2result(answer->rcode);
1867 	}
1868 
1869 out:
1870 	if (answer != NULL) {
1871 		dns_message_detach(&answer);
1872 	}
1873 	isc_event_free(&event);
1874 
1875 	LOCK(&uctx->lock);
1876 	uctx->currentserver = ISC_LIST_NEXT(uctx->currentserver, link);
1877 	dns_request_destroy(&uctx->updatereq);
1878 	/*
1879 	 * Moving on to the next server shouldn't change the result
1880 	 * for NXDOMAIN, YXDOMAIN, NXRRSET and YXRRSET as they
1881 	 * indicate a prerequisite failure.  REFUSED should also
1882 	 * be consistent across all servers but often isn't as that
1883 	 * is policy rather that zone content driven (slaves that
1884 	 * aren't willing to forward should return NOTIMPL).  NOTZONE
1885 	 * indicates that we stuffed up the request construction so
1886 	 * don't retry.
1887 	 */
1888 	if (result != ISC_R_SUCCESS && result != DNS_R_NXDOMAIN &&
1889 	    result != DNS_R_YXDOMAIN && result != DNS_R_YXRRSET &&
1890 	    result != DNS_R_NXRRSET && result != DNS_R_NOTZONE &&
1891 	    !uctx->canceled && uctx->currentserver != NULL)
1892 	{
1893 		dns_message_renderreset(uctx->updatemsg);
1894 		dns_message_settsigkey(uctx->updatemsg, NULL);
1895 
1896 		timeout = client->update_timeout / uctx->nservers;
1897 		if (timeout < MIN_UPDATE_TIMEOUT) {
1898 			timeout = MIN_UPDATE_TIMEOUT;
1899 		}
1900 		reqoptions = 0;
1901 		if (uctx->want_tcp) {
1902 			reqoptions |= DNS_REQUESTOPT_TCP;
1903 		}
1904 		result = dns_request_createvia(
1905 			uctx->view->requestmgr, uctx->updatemsg, NULL,
1906 			uctx->currentserver, -1, reqoptions, uctx->tsigkey,
1907 			timeout, client->update_udptimeout,
1908 			client->update_udpretries, client->task, update_done,
1909 			uctx, &uctx->updatereq);
1910 		UNLOCK(&uctx->lock);
1911 
1912 		if (result == ISC_R_SUCCESS) {
1913 			/* XXX: should we keep the 'done' state here? */
1914 			uctx->state = dns_clientupdatestate_sent;
1915 			return;
1916 		}
1917 	} else {
1918 		UNLOCK(&uctx->lock);
1919 	}
1920 
1921 	update_sendevent(uctx, result);
1922 }
1923 
1924 static isc_result_t
send_update(updatectx_t * uctx)1925 send_update(updatectx_t *uctx) {
1926 	isc_result_t result;
1927 	dns_name_t *name = NULL;
1928 	dns_rdataset_t *rdataset = NULL;
1929 	dns_client_t *client = uctx->client;
1930 	unsigned int timeout, reqoptions;
1931 
1932 	REQUIRE(uctx->zonename != NULL && uctx->currentserver != NULL);
1933 
1934 	result = dns_message_gettempname(uctx->updatemsg, &name);
1935 	if (result != ISC_R_SUCCESS) {
1936 		return (result);
1937 	}
1938 	dns_name_init(name, NULL);
1939 	dns_name_clone(uctx->zonename, name);
1940 	result = dns_message_gettemprdataset(uctx->updatemsg, &rdataset);
1941 	if (result != ISC_R_SUCCESS) {
1942 		dns_message_puttempname(uctx->updatemsg, &name);
1943 		return (result);
1944 	}
1945 	dns_rdataset_makequestion(rdataset, uctx->rdclass, dns_rdatatype_soa);
1946 	ISC_LIST_INIT(name->list);
1947 	ISC_LIST_APPEND(name->list, rdataset, link);
1948 	dns_message_addname(uctx->updatemsg, name, DNS_SECTION_ZONE);
1949 	if (uctx->tsigkey == NULL && uctx->sig0key != NULL) {
1950 		result = dns_message_setsig0key(uctx->updatemsg, uctx->sig0key);
1951 		if (result != ISC_R_SUCCESS) {
1952 			return (result);
1953 		}
1954 	}
1955 	timeout = client->update_timeout / uctx->nservers;
1956 	if (timeout < MIN_UPDATE_TIMEOUT) {
1957 		timeout = MIN_UPDATE_TIMEOUT;
1958 	}
1959 	reqoptions = 0;
1960 	if (uctx->want_tcp) {
1961 		reqoptions |= DNS_REQUESTOPT_TCP;
1962 	}
1963 	result = dns_request_createvia(
1964 		uctx->view->requestmgr, uctx->updatemsg, NULL,
1965 		uctx->currentserver, -1, reqoptions, uctx->tsigkey, timeout,
1966 		client->update_udptimeout, client->update_udpretries,
1967 		client->task, update_done, uctx, &uctx->updatereq);
1968 	if (result == ISC_R_SUCCESS &&
1969 	    uctx->state == dns_clientupdatestate_prepare) {
1970 		uctx->state = dns_clientupdatestate_sent;
1971 	}
1972 
1973 	return (result);
1974 }
1975 
1976 static void
resolveaddr_done(isc_task_t * task,isc_event_t * event)1977 resolveaddr_done(isc_task_t *task, isc_event_t *event) {
1978 	isc_result_t result;
1979 	int family;
1980 	dns_rdatatype_t qtype;
1981 	dns_clientresevent_t *rev = (dns_clientresevent_t *)event;
1982 	dns_name_t *name;
1983 	dns_rdataset_t *rdataset;
1984 	updatectx_t *uctx;
1985 	bool completed = false;
1986 
1987 	UNUSED(task);
1988 
1989 	REQUIRE(event->ev_arg != NULL);
1990 	uctx = *(updatectx_t **)event->ev_arg;
1991 	REQUIRE(UCTX_VALID(uctx));
1992 
1993 	if (event->ev_arg == &uctx->bp4) {
1994 		family = AF_INET;
1995 		qtype = dns_rdatatype_a;
1996 		LOCK(&uctx->lock);
1997 		dns_client_destroyrestrans(&uctx->restrans);
1998 		UNLOCK(&uctx->lock);
1999 	} else {
2000 		INSIST(event->ev_arg == &uctx->bp6);
2001 		family = AF_INET6;
2002 		qtype = dns_rdatatype_aaaa;
2003 		LOCK(&uctx->lock);
2004 		dns_client_destroyrestrans(&uctx->restrans2);
2005 		UNLOCK(&uctx->lock);
2006 	}
2007 
2008 	result = rev->result;
2009 	if (result != ISC_R_SUCCESS) {
2010 		goto done;
2011 	}
2012 
2013 	for (name = ISC_LIST_HEAD(rev->answerlist); name != NULL;
2014 	     name = ISC_LIST_NEXT(name, link))
2015 	{
2016 		for (rdataset = ISC_LIST_HEAD(name->list); rdataset != NULL;
2017 		     rdataset = ISC_LIST_NEXT(rdataset, link))
2018 		{
2019 			if (!dns_rdataset_isassociated(rdataset)) {
2020 				continue;
2021 			}
2022 			if (rdataset->type != qtype) {
2023 				continue;
2024 			}
2025 
2026 			for (result = dns_rdataset_first(rdataset);
2027 			     result == ISC_R_SUCCESS;
2028 			     result = dns_rdataset_next(rdataset))
2029 			{
2030 				dns_rdata_t rdata;
2031 				dns_rdata_in_a_t rdata_a;
2032 				dns_rdata_in_aaaa_t rdata_aaaa;
2033 				isc_sockaddr_t *sa;
2034 
2035 				sa = isc_mem_get(uctx->client->mctx,
2036 						 sizeof(*sa));
2037 
2038 				dns_rdata_init(&rdata);
2039 				switch (family) {
2040 				case AF_INET:
2041 					dns_rdataset_current(rdataset, &rdata);
2042 					result = dns_rdata_tostruct(
2043 						&rdata, &rdata_a, NULL);
2044 					RUNTIME_CHECK(result == ISC_R_SUCCESS);
2045 					isc_sockaddr_fromin(
2046 						sa, &rdata_a.in_addr, 53);
2047 					dns_rdata_freestruct(&rdata_a);
2048 					break;
2049 				case AF_INET6:
2050 					dns_rdataset_current(rdataset, &rdata);
2051 					result = dns_rdata_tostruct(
2052 						&rdata, &rdata_aaaa, NULL);
2053 					RUNTIME_CHECK(result == ISC_R_SUCCESS);
2054 					isc_sockaddr_fromin6(
2055 						sa, &rdata_aaaa.in6_addr, 53);
2056 					dns_rdata_freestruct(&rdata_aaaa);
2057 					break;
2058 				}
2059 
2060 				ISC_LINK_INIT(sa, link);
2061 				ISC_LIST_APPEND(uctx->servers, sa, link);
2062 				uctx->nservers++;
2063 			}
2064 		}
2065 	}
2066 
2067 done:
2068 	dns_client_freeresanswer(uctx->client, &rev->answerlist);
2069 	isc_event_free(&event);
2070 
2071 	LOCK(&uctx->lock);
2072 	if (uctx->restrans == NULL && uctx->restrans2 == NULL) {
2073 		completed = true;
2074 	}
2075 	UNLOCK(&uctx->lock);
2076 
2077 	if (completed) {
2078 		INSIST(uctx->currentserver == NULL);
2079 		uctx->currentserver = ISC_LIST_HEAD(uctx->servers);
2080 		if (uctx->currentserver != NULL && !uctx->canceled) {
2081 			send_update(uctx);
2082 		} else {
2083 			if (result == ISC_R_SUCCESS) {
2084 				result = ISC_R_NOTFOUND;
2085 			}
2086 			update_sendevent(uctx, result);
2087 		}
2088 	}
2089 }
2090 
2091 static isc_result_t
process_soa(updatectx_t * uctx,dns_rdataset_t * soaset,const dns_name_t * soaname)2092 process_soa(updatectx_t *uctx, dns_rdataset_t *soaset,
2093 	    const dns_name_t *soaname) {
2094 	isc_result_t result;
2095 	dns_rdata_t soarr = DNS_RDATA_INIT;
2096 	dns_rdata_soa_t soa;
2097 	dns_name_t primary;
2098 	unsigned int resoptions;
2099 
2100 	result = dns_rdataset_first(soaset);
2101 	if (result != ISC_R_SUCCESS) {
2102 		return (result);
2103 	}
2104 	dns_rdata_init(&soarr);
2105 	dns_rdataset_current(soaset, &soarr);
2106 	result = dns_rdata_tostruct(&soarr, &soa, NULL);
2107 	if (result != ISC_R_SUCCESS) {
2108 		return (result);
2109 	}
2110 
2111 	dns_name_init(&primary, NULL);
2112 	dns_name_clone(&soa.origin, &primary);
2113 
2114 	if (uctx->zonename == NULL) {
2115 		uctx->zonename = dns_fixedname_name(&uctx->zonefname);
2116 		dns_name_copynf(soaname, uctx->zonename);
2117 	}
2118 
2119 	if (uctx->currentserver != NULL) {
2120 		result = send_update(uctx);
2121 	} else {
2122 		/*
2123 		 * Get addresses of the primary server.  We don't use the ADB
2124 		 * feature so that we could avoid caching data.
2125 		 */
2126 		LOCK(&uctx->lock);
2127 		uctx->bp4 = uctx;
2128 		resoptions = 0;
2129 		if (uctx->want_tcp) {
2130 			resoptions |= DNS_CLIENTRESOPT_TCP;
2131 		}
2132 		result = dns_client_startresolve(
2133 			uctx->client, &primary, uctx->rdclass, dns_rdatatype_a,
2134 			resoptions, uctx->client->task, resolveaddr_done,
2135 			&uctx->bp4, &uctx->restrans);
2136 		if (result == ISC_R_SUCCESS) {
2137 			uctx->bp6 = uctx;
2138 			result = dns_client_startresolve(
2139 				uctx->client, &primary, uctx->rdclass,
2140 				dns_rdatatype_aaaa, resoptions,
2141 				uctx->client->task, resolveaddr_done,
2142 				&uctx->bp6, &uctx->restrans2);
2143 		}
2144 		UNLOCK(&uctx->lock);
2145 	}
2146 
2147 	dns_rdata_freestruct(&soa);
2148 
2149 	return (result);
2150 }
2151 
2152 static void
receive_soa(isc_task_t * task,isc_event_t * event)2153 receive_soa(isc_task_t *task, isc_event_t *event) {
2154 	dns_requestevent_t *reqev = NULL;
2155 	updatectx_t *uctx;
2156 	dns_client_t *client;
2157 	isc_result_t result, eresult;
2158 	dns_request_t *request;
2159 	dns_message_t *rcvmsg = NULL;
2160 	dns_section_t section;
2161 	dns_rdataset_t *soaset = NULL;
2162 	int pass = 0;
2163 	dns_name_t *name;
2164 	dns_message_t *soaquery = NULL;
2165 	isc_sockaddr_t *addr;
2166 	bool seencname = false;
2167 	bool droplabel = false;
2168 	dns_name_t tname;
2169 	unsigned int nlabels, reqoptions;
2170 
2171 	UNUSED(task);
2172 
2173 	REQUIRE(event->ev_type == DNS_EVENT_REQUESTDONE);
2174 	reqev = (dns_requestevent_t *)event;
2175 	request = reqev->request;
2176 	result = eresult = reqev->result;
2177 	POST(result);
2178 	uctx = reqev->ev_arg;
2179 	client = uctx->client;
2180 	soaquery = uctx->soaquery;
2181 	addr = uctx->currentserver;
2182 	INSIST(addr != NULL);
2183 
2184 	isc_event_free(&event);
2185 
2186 	if (eresult != ISC_R_SUCCESS) {
2187 		result = eresult;
2188 		goto out;
2189 	}
2190 
2191 	dns_message_create(uctx->client->mctx, DNS_MESSAGE_INTENTPARSE,
2192 			   &rcvmsg);
2193 	result = dns_request_getresponse(request, rcvmsg,
2194 					 DNS_MESSAGEPARSE_PRESERVEORDER);
2195 
2196 	if (result == DNS_R_TSIGERRORSET) {
2197 		dns_request_t *newrequest = NULL;
2198 
2199 		/* Retry SOA request without TSIG */
2200 		dns_message_detach(&rcvmsg);
2201 		dns_message_renderreset(uctx->soaquery);
2202 		reqoptions = 0;
2203 		if (uctx->want_tcp) {
2204 			reqoptions |= DNS_REQUESTOPT_TCP;
2205 		}
2206 		result = dns_request_createvia(
2207 			uctx->view->requestmgr, uctx->soaquery, NULL, addr, -1,
2208 			reqoptions, NULL, client->find_timeout * 20,
2209 			client->find_timeout, 3, uctx->client->task,
2210 			receive_soa, uctx, &newrequest);
2211 		if (result == ISC_R_SUCCESS) {
2212 			LOCK(&uctx->lock);
2213 			dns_request_destroy(&uctx->soareq);
2214 			uctx->soareq = newrequest;
2215 			UNLOCK(&uctx->lock);
2216 
2217 			return;
2218 		}
2219 		goto out;
2220 	}
2221 
2222 	section = DNS_SECTION_ANSWER;
2223 	POST(section);
2224 
2225 	if (rcvmsg->rcode != dns_rcode_noerror &&
2226 	    rcvmsg->rcode != dns_rcode_nxdomain) {
2227 		result = rcode2result(rcvmsg->rcode);
2228 		goto out;
2229 	}
2230 
2231 lookforsoa:
2232 	if (pass == 0) {
2233 		section = DNS_SECTION_ANSWER;
2234 	} else if (pass == 1) {
2235 		section = DNS_SECTION_AUTHORITY;
2236 	} else {
2237 		droplabel = true;
2238 		goto out;
2239 	}
2240 
2241 	result = dns_message_firstname(rcvmsg, section);
2242 	if (result != ISC_R_SUCCESS) {
2243 		pass++;
2244 		goto lookforsoa;
2245 	}
2246 	while (result == ISC_R_SUCCESS) {
2247 		name = NULL;
2248 		dns_message_currentname(rcvmsg, section, &name);
2249 		soaset = NULL;
2250 		result = dns_message_findtype(name, dns_rdatatype_soa, 0,
2251 					      &soaset);
2252 		if (result == ISC_R_SUCCESS) {
2253 			break;
2254 		}
2255 		if (section == DNS_SECTION_ANSWER) {
2256 			dns_rdataset_t *tset = NULL;
2257 			if (dns_message_findtype(name, dns_rdatatype_cname, 0,
2258 						 &tset) == ISC_R_SUCCESS ||
2259 			    dns_message_findtype(name, dns_rdatatype_dname, 0,
2260 						 &tset) == ISC_R_SUCCESS)
2261 			{
2262 				seencname = true;
2263 				break;
2264 			}
2265 		}
2266 
2267 		result = dns_message_nextname(rcvmsg, section);
2268 	}
2269 
2270 	if (soaset == NULL && !seencname) {
2271 		pass++;
2272 		goto lookforsoa;
2273 	}
2274 
2275 	if (seencname) {
2276 		droplabel = true;
2277 		goto out;
2278 	}
2279 
2280 	result = process_soa(uctx, soaset, name);
2281 
2282 out:
2283 	if (droplabel) {
2284 		result = dns_message_firstname(soaquery, DNS_SECTION_QUESTION);
2285 		INSIST(result == ISC_R_SUCCESS);
2286 		name = NULL;
2287 		dns_message_currentname(soaquery, DNS_SECTION_QUESTION, &name);
2288 		nlabels = dns_name_countlabels(name);
2289 		if (nlabels == 1) {
2290 			result = DNS_R_SERVFAIL; /* is there a better error? */
2291 		} else {
2292 			dns_name_init(&tname, NULL);
2293 			dns_name_getlabelsequence(name, 1, nlabels - 1, &tname);
2294 			dns_name_clone(&tname, name);
2295 			dns_request_destroy(&request);
2296 			LOCK(&uctx->lock);
2297 			uctx->soareq = NULL;
2298 			UNLOCK(&uctx->lock);
2299 			dns_message_renderreset(soaquery);
2300 			dns_message_settsigkey(soaquery, NULL);
2301 			reqoptions = 0;
2302 			if (uctx->want_tcp) {
2303 				reqoptions |= DNS_REQUESTOPT_TCP;
2304 			}
2305 			result = dns_request_createvia(
2306 				uctx->view->requestmgr, soaquery, NULL,
2307 				uctx->currentserver, -1, reqoptions,
2308 				uctx->tsigkey, client->find_timeout * 20,
2309 				client->find_timeout, 3, client->task,
2310 				receive_soa, uctx, &uctx->soareq);
2311 		}
2312 	}
2313 
2314 	if (!droplabel || result != ISC_R_SUCCESS) {
2315 		dns_message_detach(&uctx->soaquery);
2316 		LOCK(&uctx->lock);
2317 		dns_request_destroy(&uctx->soareq);
2318 		UNLOCK(&uctx->lock);
2319 	}
2320 
2321 	if (rcvmsg != NULL) {
2322 		dns_message_detach(&rcvmsg);
2323 	}
2324 
2325 	if (result != ISC_R_SUCCESS) {
2326 		update_sendevent(uctx, result);
2327 	}
2328 }
2329 
2330 static isc_result_t
request_soa(updatectx_t * uctx)2331 request_soa(updatectx_t *uctx) {
2332 	isc_result_t result;
2333 	dns_message_t *soaquery = uctx->soaquery;
2334 	dns_name_t *name = NULL;
2335 	dns_rdataset_t *rdataset = NULL;
2336 	unsigned int reqoptions;
2337 
2338 	if (soaquery == NULL) {
2339 		dns_message_create(uctx->client->mctx, DNS_MESSAGE_INTENTRENDER,
2340 				   &soaquery);
2341 	}
2342 	soaquery->flags |= DNS_MESSAGEFLAG_RD;
2343 	result = dns_message_gettempname(soaquery, &name);
2344 	if (result != ISC_R_SUCCESS) {
2345 		goto fail;
2346 	}
2347 	result = dns_message_gettemprdataset(soaquery, &rdataset);
2348 	if (result != ISC_R_SUCCESS) {
2349 		goto fail;
2350 	}
2351 	dns_rdataset_makequestion(rdataset, uctx->rdclass, dns_rdatatype_soa);
2352 	dns_name_clone(uctx->firstname, name);
2353 	ISC_LIST_APPEND(name->list, rdataset, link);
2354 	dns_message_addname(soaquery, name, DNS_SECTION_QUESTION);
2355 	rdataset = NULL;
2356 	name = NULL;
2357 	reqoptions = 0;
2358 	if (uctx->want_tcp) {
2359 		reqoptions |= DNS_REQUESTOPT_TCP;
2360 	}
2361 
2362 	result = dns_request_createvia(
2363 		uctx->view->requestmgr, soaquery, NULL, uctx->currentserver, -1,
2364 		reqoptions, uctx->tsigkey, uctx->client->find_timeout * 20,
2365 		uctx->client->find_timeout, 3, uctx->client->task, receive_soa,
2366 		uctx, &uctx->soareq);
2367 	if (result == ISC_R_SUCCESS) {
2368 		uctx->soaquery = soaquery;
2369 		return (ISC_R_SUCCESS);
2370 	}
2371 
2372 fail:
2373 	if (rdataset != NULL) {
2374 		ISC_LIST_UNLINK(name->list, rdataset, link); /* for safety */
2375 		dns_message_puttemprdataset(soaquery, &rdataset);
2376 	}
2377 	if (name != NULL) {
2378 		dns_message_puttempname(soaquery, &name);
2379 	}
2380 	dns_message_detach(&soaquery);
2381 
2382 	return (result);
2383 }
2384 
2385 static void
resolvesoa_done(isc_task_t * task,isc_event_t * event)2386 resolvesoa_done(isc_task_t *task, isc_event_t *event) {
2387 	dns_clientresevent_t *rev = (dns_clientresevent_t *)event;
2388 	updatectx_t *uctx;
2389 	dns_name_t *name, tname;
2390 	dns_rdataset_t *rdataset = NULL;
2391 	isc_result_t result = rev->result;
2392 	unsigned int nlabels, resoptions;
2393 
2394 	UNUSED(task);
2395 
2396 	uctx = event->ev_arg;
2397 	REQUIRE(UCTX_VALID(uctx));
2398 
2399 	LOCK(&uctx->lock);
2400 	dns_client_destroyrestrans(&uctx->restrans);
2401 	UNLOCK(&uctx->lock);
2402 
2403 	uctx = event->ev_arg;
2404 	if (result != ISC_R_SUCCESS && result != DNS_R_NCACHENXDOMAIN &&
2405 	    result != DNS_R_NCACHENXRRSET)
2406 	{
2407 		/* XXX: what about DNSSEC failure? */
2408 		goto out;
2409 	}
2410 
2411 	for (name = ISC_LIST_HEAD(rev->answerlist); name != NULL;
2412 	     name = ISC_LIST_NEXT(name, link))
2413 	{
2414 		for (rdataset = ISC_LIST_HEAD(name->list); rdataset != NULL;
2415 		     rdataset = ISC_LIST_NEXT(rdataset, link))
2416 		{
2417 			if (dns_rdataset_isassociated(rdataset) &&
2418 			    rdataset->type == dns_rdatatype_soa) {
2419 				break;
2420 			}
2421 		}
2422 	}
2423 
2424 	if (rdataset == NULL) {
2425 		/* Drop one label and retry resolution. */
2426 		nlabels = dns_name_countlabels(&uctx->soaqname);
2427 		if (nlabels == 1) {
2428 			result = DNS_R_SERVFAIL; /* is there a better error? */
2429 			goto out;
2430 		}
2431 		dns_name_init(&tname, NULL);
2432 		dns_name_getlabelsequence(&uctx->soaqname, 1, nlabels - 1,
2433 					  &tname);
2434 		dns_name_clone(&tname, &uctx->soaqname);
2435 		resoptions = 0;
2436 		if (uctx->want_tcp) {
2437 			resoptions |= DNS_CLIENTRESOPT_TCP;
2438 		}
2439 
2440 		result = dns_client_startresolve(
2441 			uctx->client, &uctx->soaqname, uctx->rdclass,
2442 			dns_rdatatype_soa, resoptions, uctx->client->task,
2443 			resolvesoa_done, uctx, &uctx->restrans);
2444 	} else {
2445 		result = process_soa(uctx, rdataset, &uctx->soaqname);
2446 	}
2447 
2448 out:
2449 	dns_client_freeresanswer(uctx->client, &rev->answerlist);
2450 	isc_event_free(&event);
2451 
2452 	if (result != ISC_R_SUCCESS) {
2453 		update_sendevent(uctx, result);
2454 	}
2455 }
2456 
2457 static isc_result_t
copy_name(isc_mem_t * mctx,dns_message_t * msg,const dns_name_t * name,dns_name_t ** newnamep)2458 copy_name(isc_mem_t *mctx, dns_message_t *msg, const dns_name_t *name,
2459 	  dns_name_t **newnamep) {
2460 	isc_result_t result;
2461 	dns_name_t *newname = NULL;
2462 	isc_region_t r;
2463 	isc_buffer_t *namebuf = NULL, *rdatabuf = NULL;
2464 	dns_rdatalist_t *rdatalist;
2465 	dns_rdataset_t *rdataset, *newrdataset;
2466 	dns_rdata_t rdata = DNS_RDATA_INIT, *newrdata;
2467 
2468 	result = dns_message_gettempname(msg, &newname);
2469 	if (result != ISC_R_SUCCESS) {
2470 		return (result);
2471 	}
2472 	isc_buffer_allocate(mctx, &namebuf, DNS_NAME_MAXWIRE);
2473 	dns_name_init(newname, NULL);
2474 	dns_name_setbuffer(newname, namebuf);
2475 	dns_message_takebuffer(msg, &namebuf);
2476 	dns_name_copynf(name, newname);
2477 
2478 	for (rdataset = ISC_LIST_HEAD(name->list); rdataset != NULL;
2479 	     rdataset = ISC_LIST_NEXT(rdataset, link))
2480 	{
2481 		rdatalist = NULL;
2482 		result = dns_message_gettemprdatalist(msg, &rdatalist);
2483 		if (result != ISC_R_SUCCESS) {
2484 			goto fail;
2485 		}
2486 		dns_rdatalist_init(rdatalist);
2487 		rdatalist->type = rdataset->type;
2488 		rdatalist->rdclass = rdataset->rdclass;
2489 		rdatalist->covers = rdataset->covers;
2490 		rdatalist->ttl = rdataset->ttl;
2491 
2492 		result = dns_rdataset_first(rdataset);
2493 		while (result == ISC_R_SUCCESS) {
2494 			dns_rdata_reset(&rdata);
2495 			dns_rdataset_current(rdataset, &rdata);
2496 
2497 			newrdata = NULL;
2498 			result = dns_message_gettemprdata(msg, &newrdata);
2499 			if (result != ISC_R_SUCCESS) {
2500 				goto fail;
2501 			}
2502 			dns_rdata_toregion(&rdata, &r);
2503 			rdatabuf = NULL;
2504 			isc_buffer_allocate(mctx, &rdatabuf, r.length);
2505 			isc_buffer_putmem(rdatabuf, r.base, r.length);
2506 			isc_buffer_usedregion(rdatabuf, &r);
2507 			dns_rdata_init(newrdata);
2508 			dns_rdata_fromregion(newrdata, rdata.rdclass,
2509 					     rdata.type, &r);
2510 			newrdata->flags = rdata.flags;
2511 
2512 			ISC_LIST_APPEND(rdatalist->rdata, newrdata, link);
2513 			dns_message_takebuffer(msg, &rdatabuf);
2514 
2515 			result = dns_rdataset_next(rdataset);
2516 		}
2517 
2518 		newrdataset = NULL;
2519 		result = dns_message_gettemprdataset(msg, &newrdataset);
2520 		if (result != ISC_R_SUCCESS) {
2521 			goto fail;
2522 		}
2523 		dns_rdatalist_tordataset(rdatalist, newrdataset);
2524 
2525 		ISC_LIST_APPEND(newname->list, newrdataset, link);
2526 	}
2527 
2528 	*newnamep = newname;
2529 
2530 	return (ISC_R_SUCCESS);
2531 
2532 fail:
2533 	dns_message_puttempname(msg, &newname);
2534 
2535 	return (result);
2536 }
2537 
2538 static void
internal_update_callback(isc_task_t * task,isc_event_t * event)2539 internal_update_callback(isc_task_t *task, isc_event_t *event) {
2540 	updatearg_t *uarg = event->ev_arg;
2541 	dns_clientupdateevent_t *uev = (dns_clientupdateevent_t *)event;
2542 
2543 	UNUSED(task);
2544 
2545 	LOCK(&uarg->lock);
2546 
2547 	uarg->result = uev->result;
2548 
2549 	dns_client_destroyupdatetrans(&uarg->trans);
2550 	isc_event_free(&event);
2551 
2552 	if (!uarg->canceled) {
2553 		UNLOCK(&uarg->lock);
2554 
2555 		/* Exit from the internal event loop */
2556 		isc_app_ctxsuspend(uarg->actx);
2557 	} else {
2558 		/*
2559 		 * We have already exited from the loop (due to some
2560 		 * unexpected event).  Just clean the arg up.
2561 		 */
2562 		UNLOCK(&uarg->lock);
2563 		isc_mutex_destroy(&uarg->lock);
2564 		isc_mem_put(uarg->client->mctx, uarg, sizeof(*uarg));
2565 	}
2566 }
2567 
2568 isc_result_t
dns_client_update(dns_client_t * client,dns_rdataclass_t rdclass,const dns_name_t * zonename,dns_namelist_t * prerequisites,dns_namelist_t * updates,isc_sockaddrlist_t * servers,dns_tsec_t * tsec,unsigned int options)2569 dns_client_update(dns_client_t *client, dns_rdataclass_t rdclass,
2570 		  const dns_name_t *zonename, dns_namelist_t *prerequisites,
2571 		  dns_namelist_t *updates, isc_sockaddrlist_t *servers,
2572 		  dns_tsec_t *tsec, unsigned int options) {
2573 	isc_result_t result;
2574 	isc_appctx_t *actx;
2575 	updatearg_t *uarg;
2576 
2577 	REQUIRE(DNS_CLIENT_VALID(client));
2578 
2579 	if ((client->attributes & DNS_CLIENTATTR_OWNCTX) == 0 &&
2580 	    (options & DNS_CLIENTUPDOPT_ALLOWRUN) == 0)
2581 	{
2582 		/*
2583 		 * If the client is run under application's control, we need
2584 		 * to create a new running (sub)environment for this
2585 		 * particular update.
2586 		 */
2587 		return (ISC_R_NOTIMPLEMENTED); /* XXXTBD */
2588 	} else {
2589 		actx = client->actx;
2590 	}
2591 
2592 	uarg = isc_mem_get(client->mctx, sizeof(*uarg));
2593 
2594 	isc_mutex_init(&uarg->lock);
2595 
2596 	uarg->actx = actx;
2597 	uarg->client = client;
2598 	uarg->result = ISC_R_FAILURE;
2599 	uarg->trans = NULL;
2600 	uarg->canceled = false;
2601 
2602 	result = dns_client_startupdate(
2603 		client, rdclass, zonename, prerequisites, updates, servers,
2604 		tsec, options, client->task, internal_update_callback, uarg,
2605 		&uarg->trans);
2606 	if (result != ISC_R_SUCCESS) {
2607 		isc_mutex_destroy(&uarg->lock);
2608 		isc_mem_put(client->mctx, uarg, sizeof(*uarg));
2609 		return (result);
2610 	}
2611 
2612 	/*
2613 	 * Start internal event loop.  It blocks until the entire process
2614 	 * is completed.
2615 	 */
2616 	result = isc_app_ctxrun(actx);
2617 
2618 	LOCK(&uarg->lock);
2619 	if (result == ISC_R_SUCCESS || result == ISC_R_SUSPEND) {
2620 		result = uarg->result;
2621 	}
2622 
2623 	if (uarg->trans != NULL) {
2624 		/*
2625 		 * Unusual termination (perhaps due to signal).  We need some
2626 		 * tricky cleanup process.
2627 		 */
2628 		uarg->canceled = true;
2629 		dns_client_cancelupdate(uarg->trans);
2630 
2631 		UNLOCK(&uarg->lock);
2632 
2633 		/* uarg will be freed in the event handler. */
2634 	} else {
2635 		UNLOCK(&uarg->lock);
2636 
2637 		isc_mutex_destroy(&uarg->lock);
2638 		isc_mem_put(client->mctx, uarg, sizeof(*uarg));
2639 	}
2640 
2641 	return (result);
2642 }
2643 
2644 static void
startupdate(isc_task_t * task,isc_event_t * event)2645 startupdate(isc_task_t *task, isc_event_t *event) {
2646 	updatectx_t *uctx;
2647 	isc_result_t result;
2648 	unsigned int resoptions;
2649 
2650 	REQUIRE(event != NULL);
2651 
2652 	UNUSED(task);
2653 
2654 	uctx = event->ev_arg;
2655 
2656 	if (uctx->zonename != NULL && uctx->currentserver != NULL) {
2657 		result = send_update(uctx);
2658 		if (result != ISC_R_SUCCESS) {
2659 			goto fail;
2660 		}
2661 	} else if (uctx->currentserver != NULL) {
2662 		result = request_soa(uctx);
2663 		if (result != ISC_R_SUCCESS) {
2664 			goto fail;
2665 		}
2666 	} else {
2667 		resoptions = 0;
2668 		if (uctx->want_tcp) {
2669 			resoptions |= DNS_CLIENTRESOPT_TCP;
2670 		}
2671 		dns_name_clone(uctx->firstname, &uctx->soaqname);
2672 		result = dns_client_startresolve(
2673 			uctx->client, &uctx->soaqname, uctx->rdclass,
2674 			dns_rdatatype_soa, resoptions, uctx->client->task,
2675 			resolvesoa_done, uctx, &uctx->restrans);
2676 		if (result != ISC_R_SUCCESS) {
2677 			goto fail;
2678 		}
2679 	}
2680 
2681 	isc_event_free(&event);
2682 
2683 fail:
2684 	if (result != ISC_R_SUCCESS) {
2685 		update_sendevent(uctx, result);
2686 	}
2687 }
2688 
2689 isc_result_t
dns_client_startupdate(dns_client_t * client,dns_rdataclass_t rdclass,const dns_name_t * zonename,dns_namelist_t * prerequisites,dns_namelist_t * updates,isc_sockaddrlist_t * servers,dns_tsec_t * tsec,unsigned int options,isc_task_t * task,isc_taskaction_t action,void * arg,dns_clientupdatetrans_t ** transp)2690 dns_client_startupdate(dns_client_t *client, dns_rdataclass_t rdclass,
2691 		       const dns_name_t *zonename,
2692 		       dns_namelist_t *prerequisites, dns_namelist_t *updates,
2693 		       isc_sockaddrlist_t *servers, dns_tsec_t *tsec,
2694 		       unsigned int options, isc_task_t *task,
2695 		       isc_taskaction_t action, void *arg,
2696 		       dns_clientupdatetrans_t **transp) {
2697 	dns_view_t *view = NULL;
2698 	isc_result_t result;
2699 	dns_name_t *name, *newname;
2700 	updatectx_t *uctx;
2701 	isc_task_t *tclone = NULL;
2702 	dns_section_t section = DNS_SECTION_UPDATE;
2703 	isc_sockaddr_t *server, *sa = NULL;
2704 	dns_tsectype_t tsectype = dns_tsectype_none;
2705 	bool want_tcp;
2706 
2707 	UNUSED(options);
2708 
2709 	REQUIRE(DNS_CLIENT_VALID(client));
2710 	REQUIRE(transp != NULL && *transp == NULL);
2711 	REQUIRE(updates != NULL);
2712 	REQUIRE(task != NULL);
2713 
2714 	if (tsec != NULL) {
2715 		tsectype = dns_tsec_gettype(tsec);
2716 		if (tsectype != dns_tsectype_tsig) {
2717 			return (ISC_R_NOTIMPLEMENTED); /* XXX */
2718 		}
2719 	}
2720 
2721 	LOCK(&client->lock);
2722 	result = dns_viewlist_find(&client->viewlist, DNS_CLIENTVIEW_NAME,
2723 				   rdclass, &view);
2724 	UNLOCK(&client->lock);
2725 	if (result != ISC_R_SUCCESS) {
2726 		return (result);
2727 	}
2728 
2729 	want_tcp = ((options & DNS_CLIENTUPDOPT_TCP) != 0);
2730 
2731 	/*
2732 	 * Create a context and prepare some resources.
2733 	 */
2734 
2735 	uctx = isc_mem_get(client->mctx, sizeof(*uctx));
2736 
2737 	isc_mutex_init(&uctx->lock);
2738 
2739 	tclone = NULL;
2740 	isc_task_attach(task, &tclone);
2741 	uctx->client = client;
2742 	ISC_LINK_INIT(uctx, link);
2743 	uctx->state = dns_clientupdatestate_prepare;
2744 	uctx->view = view;
2745 	uctx->rdclass = rdclass;
2746 	uctx->canceled = false;
2747 	uctx->updatemsg = NULL;
2748 	uctx->soaquery = NULL;
2749 	uctx->updatereq = NULL;
2750 	uctx->restrans = NULL;
2751 	uctx->restrans2 = NULL;
2752 	uctx->bp4 = NULL;
2753 	uctx->bp6 = NULL;
2754 	uctx->soareq = NULL;
2755 	uctx->event = NULL;
2756 	uctx->tsigkey = NULL;
2757 	uctx->sig0key = NULL;
2758 	uctx->zonename = NULL;
2759 	uctx->want_tcp = want_tcp;
2760 	dns_name_init(&uctx->soaqname, NULL);
2761 	ISC_LIST_INIT(uctx->servers);
2762 	uctx->nservers = 0;
2763 	uctx->currentserver = NULL;
2764 	dns_fixedname_init(&uctx->zonefname);
2765 	if (tsec != NULL) {
2766 		dns_tsec_getkey(tsec, &uctx->tsigkey);
2767 	}
2768 	uctx->event = (dns_clientupdateevent_t *)isc_event_allocate(
2769 		client->mctx, tclone, DNS_EVENT_UPDATEDONE, action, arg,
2770 		sizeof(*uctx->event));
2771 	if (zonename != NULL) {
2772 		uctx->zonename = dns_fixedname_name(&uctx->zonefname);
2773 		dns_name_copynf(zonename, uctx->zonename);
2774 	}
2775 	if (servers != NULL) {
2776 		for (server = ISC_LIST_HEAD(*servers); server != NULL;
2777 		     server = ISC_LIST_NEXT(server, link))
2778 		{
2779 			sa = isc_mem_get(client->mctx, sizeof(*sa));
2780 			sa->type = server->type;
2781 			sa->length = server->length;
2782 			ISC_LINK_INIT(sa, link);
2783 			ISC_LIST_APPEND(uctx->servers, sa, link);
2784 			if (uctx->currentserver == NULL) {
2785 				uctx->currentserver = sa;
2786 			}
2787 			uctx->nservers++;
2788 		}
2789 	}
2790 
2791 	/* Make update message */
2792 	dns_message_create(client->mctx, DNS_MESSAGE_INTENTRENDER,
2793 			   &uctx->updatemsg);
2794 	uctx->updatemsg->opcode = dns_opcode_update;
2795 
2796 	if (prerequisites != NULL) {
2797 		for (name = ISC_LIST_HEAD(*prerequisites); name != NULL;
2798 		     name = ISC_LIST_NEXT(name, link))
2799 		{
2800 			newname = NULL;
2801 			result = copy_name(client->mctx, uctx->updatemsg, name,
2802 					   &newname);
2803 			if (result != ISC_R_SUCCESS) {
2804 				goto fail;
2805 			}
2806 			dns_message_addname(uctx->updatemsg, newname,
2807 					    DNS_SECTION_PREREQUISITE);
2808 		}
2809 	}
2810 
2811 	for (name = ISC_LIST_HEAD(*updates); name != NULL;
2812 	     name = ISC_LIST_NEXT(name, link))
2813 	{
2814 		newname = NULL;
2815 		result = copy_name(client->mctx, uctx->updatemsg, name,
2816 				   &newname);
2817 		if (result != ISC_R_SUCCESS) {
2818 			goto fail;
2819 		}
2820 		dns_message_addname(uctx->updatemsg, newname,
2821 				    DNS_SECTION_UPDATE);
2822 	}
2823 
2824 	uctx->firstname = NULL;
2825 	result = dns_message_firstname(uctx->updatemsg, section);
2826 	if (result == ISC_R_NOMORE) {
2827 		section = DNS_SECTION_PREREQUISITE;
2828 		result = dns_message_firstname(uctx->updatemsg, section);
2829 	}
2830 	if (result != ISC_R_SUCCESS) {
2831 		goto fail;
2832 	}
2833 	dns_message_currentname(uctx->updatemsg, section, &uctx->firstname);
2834 
2835 	uctx->magic = UCTX_MAGIC;
2836 
2837 	LOCK(&client->lock);
2838 	ISC_LIST_APPEND(client->updatectxs, uctx, link);
2839 	isc_refcount_increment(&client->references);
2840 	UNLOCK(&client->lock);
2841 
2842 	*transp = (dns_clientupdatetrans_t *)uctx;
2843 	result = isc_app_ctxonrun(client->actx, client->mctx, client->task,
2844 				  startupdate, uctx);
2845 	if (result == ISC_R_ALREADYRUNNING) {
2846 		isc_event_t *event;
2847 		event = isc_event_allocate(client->mctx, dns_client_startupdate,
2848 					   DNS_EVENT_STARTUPDATE, startupdate,
2849 					   uctx, sizeof(*event));
2850 		result = ISC_R_SUCCESS;
2851 		isc_task_send(task, &event);
2852 	}
2853 	if (result == ISC_R_SUCCESS) {
2854 		return (result);
2855 	}
2856 
2857 	isc_refcount_decrement1(&client->references);
2858 	*transp = NULL;
2859 
2860 fail:
2861 	if (ISC_LINK_LINKED(uctx, link)) {
2862 		LOCK(&client->lock);
2863 		ISC_LIST_UNLINK(client->updatectxs, uctx, link);
2864 		UNLOCK(&client->lock);
2865 	}
2866 	if (uctx->updatemsg != NULL) {
2867 		dns_message_detach(&uctx->updatemsg);
2868 	}
2869 	while ((sa = ISC_LIST_HEAD(uctx->servers)) != NULL) {
2870 		ISC_LIST_UNLINK(uctx->servers, sa, link);
2871 		isc_mem_put(client->mctx, sa, sizeof(*sa));
2872 	}
2873 	if (uctx->event != NULL) {
2874 		isc_event_free(ISC_EVENT_PTR(&uctx->event));
2875 	}
2876 	if (uctx->tsigkey != NULL) {
2877 		dns_tsigkey_detach(&uctx->tsigkey);
2878 	}
2879 	isc_task_detach(&tclone);
2880 	isc_mutex_destroy(&uctx->lock);
2881 	uctx->magic = 0;
2882 	isc_mem_put(client->mctx, uctx, sizeof(*uctx));
2883 	dns_view_detach(&view);
2884 
2885 	return (result);
2886 }
2887 
2888 void
dns_client_cancelupdate(dns_clientupdatetrans_t * trans)2889 dns_client_cancelupdate(dns_clientupdatetrans_t *trans) {
2890 	updatectx_t *uctx;
2891 
2892 	REQUIRE(trans != NULL);
2893 	uctx = (updatectx_t *)trans;
2894 	REQUIRE(UCTX_VALID(uctx));
2895 
2896 	LOCK(&uctx->lock);
2897 
2898 	if (!uctx->canceled) {
2899 		uctx->canceled = true;
2900 		if (uctx->updatereq != NULL) {
2901 			dns_request_cancel(uctx->updatereq);
2902 		}
2903 		if (uctx->soareq != NULL) {
2904 			dns_request_cancel(uctx->soareq);
2905 		}
2906 		if (uctx->restrans != NULL) {
2907 			dns_client_cancelresolve(uctx->restrans);
2908 		}
2909 		if (uctx->restrans2 != NULL) {
2910 			dns_client_cancelresolve(uctx->restrans2);
2911 		}
2912 	}
2913 
2914 	UNLOCK(&uctx->lock);
2915 }
2916 
2917 void
dns_client_destroyupdatetrans(dns_clientupdatetrans_t ** transp)2918 dns_client_destroyupdatetrans(dns_clientupdatetrans_t **transp) {
2919 	updatectx_t *uctx;
2920 	isc_mem_t *mctx;
2921 	dns_client_t *client;
2922 	isc_sockaddr_t *sa;
2923 
2924 	REQUIRE(transp != NULL);
2925 	uctx = (updatectx_t *)*transp;
2926 	*transp = NULL;
2927 	REQUIRE(UCTX_VALID(uctx));
2928 	client = uctx->client;
2929 	REQUIRE(DNS_CLIENT_VALID(client));
2930 	REQUIRE(uctx->updatereq == NULL && uctx->updatemsg == NULL &&
2931 		uctx->soareq == NULL && uctx->soaquery == NULL &&
2932 		uctx->event == NULL && uctx->tsigkey == NULL &&
2933 		uctx->sig0key == NULL);
2934 
2935 	mctx = client->mctx;
2936 	dns_view_detach(&uctx->view);
2937 	while ((sa = ISC_LIST_HEAD(uctx->servers)) != NULL) {
2938 		ISC_LIST_UNLINK(uctx->servers, sa, link);
2939 		isc_mem_put(mctx, sa, sizeof(*sa));
2940 	}
2941 
2942 	LOCK(&client->lock);
2943 
2944 	INSIST(ISC_LINK_LINKED(uctx, link));
2945 	ISC_LIST_UNLINK(client->updatectxs, uctx, link);
2946 
2947 	UNLOCK(&client->lock);
2948 
2949 	isc_mutex_destroy(&uctx->lock);
2950 	uctx->magic = 0;
2951 
2952 	isc_mem_put(mctx, uctx, sizeof(*uctx));
2953 
2954 	dns_client_destroy(&client);
2955 }
2956 
2957 isc_mem_t *
dns_client_mctx(dns_client_t * client)2958 dns_client_mctx(dns_client_t *client) {
2959 	REQUIRE(DNS_CLIENT_VALID(client));
2960 	return (client->mctx);
2961 }
2962 
2963 typedef struct {
2964 	isc_buffer_t buffer;
2965 	dns_rdataset_t rdataset;
2966 	dns_rdatalist_t rdatalist;
2967 	dns_rdata_t rdata;
2968 	size_t size;
2969 	isc_mem_t *mctx;
2970 	unsigned char data[FLEXIBLE_ARRAY_MEMBER];
2971 } dns_client_updaterec_t;
2972 
2973 isc_result_t
dns_client_updaterec(dns_client_updateop_t op,const dns_name_t * owner,dns_rdatatype_t type,dns_rdata_t * source,dns_ttl_t ttl,dns_name_t * target,dns_rdataset_t * rdataset,dns_rdatalist_t * rdatalist,dns_rdata_t * rdata,isc_mem_t * mctx)2974 dns_client_updaterec(dns_client_updateop_t op, const dns_name_t *owner,
2975 		     dns_rdatatype_t type, dns_rdata_t *source, dns_ttl_t ttl,
2976 		     dns_name_t *target, dns_rdataset_t *rdataset,
2977 		     dns_rdatalist_t *rdatalist, dns_rdata_t *rdata,
2978 		     isc_mem_t *mctx) {
2979 	dns_client_updaterec_t *updaterec = NULL;
2980 	size_t size = offsetof(dns_client_updaterec_t, data);
2981 
2982 	REQUIRE(op < updateop_max);
2983 	REQUIRE(owner != NULL);
2984 	REQUIRE((rdataset != NULL && rdatalist != NULL && rdata != NULL) ||
2985 		(rdataset == NULL && rdatalist == NULL && rdata == NULL &&
2986 		 mctx != NULL));
2987 	if (op == updateop_add) {
2988 		REQUIRE(source != NULL);
2989 	}
2990 	if (source != NULL) {
2991 		REQUIRE(source->type == type);
2992 		REQUIRE(op == updateop_add || op == updateop_delete ||
2993 			op == updateop_exist);
2994 	}
2995 
2996 	size += owner->length;
2997 	if (source != NULL) {
2998 		size += source->length;
2999 	}
3000 
3001 	if (rdataset == NULL) {
3002 		updaterec = isc_mem_get(mctx, size);
3003 		rdataset = &updaterec->rdataset;
3004 		rdatalist = &updaterec->rdatalist;
3005 		rdata = &updaterec->rdata;
3006 		dns_rdataset_init(rdataset);
3007 		dns_rdatalist_init(&updaterec->rdatalist);
3008 		dns_rdata_init(&updaterec->rdata);
3009 		isc_buffer_init(
3010 			&updaterec->buffer, updaterec->data,
3011 			(unsigned int)(size -
3012 				       offsetof(dns_client_updaterec_t, data)));
3013 		dns_name_copy(owner, target, &updaterec->buffer);
3014 		if (source != NULL) {
3015 			isc_region_t r;
3016 			dns_rdata_clone(source, rdata);
3017 			dns_rdata_toregion(rdata, &r);
3018 			rdata->data = isc_buffer_used(&updaterec->buffer);
3019 			isc_buffer_copyregion(&updaterec->buffer, &r);
3020 		}
3021 		updaterec->mctx = NULL;
3022 		isc_mem_attach(mctx, &updaterec->mctx);
3023 	} else if (source != NULL) {
3024 		dns_rdata_clone(source, rdata);
3025 	}
3026 
3027 	switch (op) {
3028 	case updateop_add:
3029 		break;
3030 	case updateop_delete:
3031 		if (source != NULL) {
3032 			ttl = 0;
3033 			dns_rdata_makedelete(rdata);
3034 		} else {
3035 			dns_rdata_deleterrset(rdata, type);
3036 		}
3037 		break;
3038 	case updateop_notexist:
3039 		dns_rdata_notexist(rdata, type);
3040 		break;
3041 	case updateop_exist:
3042 		if (source == NULL) {
3043 			ttl = 0;
3044 			dns_rdata_exists(rdata, type);
3045 		}
3046 	case updateop_none:
3047 		break;
3048 	default:
3049 		INSIST(0);
3050 		ISC_UNREACHABLE();
3051 	}
3052 
3053 	rdatalist->type = rdata->type;
3054 	rdatalist->rdclass = rdata->rdclass;
3055 	if (source != NULL) {
3056 		rdatalist->covers = dns_rdata_covers(rdata);
3057 		rdatalist->ttl = ttl;
3058 	}
3059 	ISC_LIST_APPEND(rdatalist->rdata, rdata, link);
3060 	dns_rdatalist_tordataset(rdatalist, rdataset);
3061 	ISC_LIST_APPEND(target->list, rdataset, link);
3062 	if (updaterec != NULL) {
3063 		target->attributes |= DNS_NAMEATTR_HASUPDATEREC;
3064 		dns_name_setbuffer(target, &updaterec->buffer);
3065 	}
3066 	if (op == updateop_add || op == updateop_delete) {
3067 		target->attributes |= DNS_NAMEATTR_UPDATE;
3068 	} else {
3069 		target->attributes |= DNS_NAMEATTR_PREREQUISITE;
3070 	}
3071 	return (ISC_R_SUCCESS);
3072 }
3073 
3074 void
dns_client_freeupdate(dns_name_t ** namep)3075 dns_client_freeupdate(dns_name_t **namep) {
3076 	dns_client_updaterec_t *updaterec;
3077 	dns_rdatalist_t *rdatalist;
3078 	dns_rdataset_t *rdataset;
3079 	dns_rdata_t *rdata;
3080 	dns_name_t *name;
3081 
3082 	REQUIRE(namep != NULL && *namep != NULL);
3083 
3084 	name = *namep;
3085 	for (rdataset = ISC_LIST_HEAD(name->list); rdataset != NULL;
3086 	     rdataset = ISC_LIST_HEAD(name->list))
3087 	{
3088 		ISC_LIST_UNLINK(name->list, rdataset, link);
3089 		rdatalist = NULL;
3090 		dns_rdatalist_fromrdataset(rdataset, &rdatalist);
3091 		if (rdatalist == NULL) {
3092 			dns_rdataset_disassociate(rdataset);
3093 			continue;
3094 		}
3095 		for (rdata = ISC_LIST_HEAD(rdatalist->rdata); rdata != NULL;
3096 		     rdata = ISC_LIST_HEAD(rdatalist->rdata))
3097 		{
3098 			ISC_LIST_UNLINK(rdatalist->rdata, rdata, link);
3099 		}
3100 		dns_rdataset_disassociate(rdataset);
3101 	}
3102 
3103 	if ((name->attributes & DNS_NAMEATTR_HASUPDATEREC) != 0) {
3104 		updaterec = (dns_client_updaterec_t *)name->buffer;
3105 		INSIST(updaterec != NULL);
3106 		isc_mem_putanddetach(&updaterec->mctx, updaterec,
3107 				     updaterec->size);
3108 		*namep = NULL;
3109 	}
3110 }
3111