Merge branch 'vendor/OPENSSH'
[dragonfly.git] / contrib / bind / lib / dns / request.c
1 /*
2  * Copyright (C) 2004-2009  Internet Systems Consortium, Inc. ("ISC")
3  * Copyright (C) 2000-2002  Internet Software Consortium.
4  *
5  * Permission to use, copy, modify, and/or distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15  * PERFORMANCE OF THIS SOFTWARE.
16  */
17
18 /* $Id: request.c,v 1.79.128.5 2009/01/19 23:47:02 tbox Exp $ */
19
20 /*! \file */
21
22 #include <config.h>
23
24 #include <isc/magic.h>
25 #include <isc/mem.h>
26 #include <isc/task.h>
27 #include <isc/timer.h>
28 #include <isc/util.h>
29
30 #include <dns/acl.h>
31 #include <dns/compress.h>
32 #include <dns/dispatch.h>
33 #include <dns/events.h>
34 #include <dns/log.h>
35 #include <dns/message.h>
36 #include <dns/rdata.h>
37 #include <dns/rdatastruct.h>
38 #include <dns/request.h>
39 #include <dns/result.h>
40 #include <dns/tsig.h>
41
42 #define REQUESTMGR_MAGIC        ISC_MAGIC('R', 'q', 'u', 'M')
43 #define VALID_REQUESTMGR(mgr)   ISC_MAGIC_VALID(mgr, REQUESTMGR_MAGIC)
44
45 #define REQUEST_MAGIC           ISC_MAGIC('R', 'q', 'u', '!')
46 #define VALID_REQUEST(request)  ISC_MAGIC_VALID(request, REQUEST_MAGIC)
47
48 typedef ISC_LIST(dns_request_t) dns_requestlist_t;
49
50 #define DNS_REQUEST_NLOCKS 7
51
52 struct dns_requestmgr {
53         unsigned int                    magic;
54         isc_mutex_t                     lock;
55         isc_mem_t                      *mctx;
56
57         /* locked */
58         isc_int32_t                     eref;
59         isc_int32_t                     iref;
60         isc_timermgr_t                 *timermgr;
61         isc_socketmgr_t                *socketmgr;
62         isc_taskmgr_t                  *taskmgr;
63         dns_dispatchmgr_t              *dispatchmgr;
64         dns_dispatch_t                 *dispatchv4;
65         dns_dispatch_t                 *dispatchv6;
66         isc_boolean_t                   exiting;
67         isc_eventlist_t                 whenshutdown;
68         unsigned int                    hash;
69         isc_mutex_t                     locks[DNS_REQUEST_NLOCKS];
70         dns_requestlist_t               requests;
71 };
72
73 struct dns_request {
74         unsigned int                    magic;
75         unsigned int                    hash;
76         isc_mem_t                      *mctx;
77         isc_int32_t                     flags;
78         ISC_LINK(dns_request_t)         link;
79         isc_buffer_t                   *query;
80         isc_buffer_t                   *answer;
81         dns_requestevent_t             *event;
82         dns_dispatch_t                 *dispatch;
83         dns_dispentry_t                *dispentry;
84         isc_timer_t                    *timer;
85         dns_requestmgr_t               *requestmgr;
86         isc_buffer_t                   *tsig;
87         dns_tsigkey_t                  *tsigkey;
88         isc_event_t                     ctlevent;
89         isc_boolean_t                   canceling; /* ctlevent outstanding */
90         isc_sockaddr_t                  destaddr;
91         unsigned int                    udpcount;
92 };
93
94 #define DNS_REQUEST_F_CONNECTING 0x0001
95 #define DNS_REQUEST_F_SENDING 0x0002
96 #define DNS_REQUEST_F_CANCELED 0x0004   /*%< ctlevent received, or otherwise
97                                            synchronously canceled */
98 #define DNS_REQUEST_F_TIMEDOUT 0x0008   /*%< canceled due to a timeout */
99 #define DNS_REQUEST_F_TCP 0x0010        /*%< This request used TCP */
100 #define DNS_REQUEST_CANCELED(r) \
101         (((r)->flags & DNS_REQUEST_F_CANCELED) != 0)
102 #define DNS_REQUEST_CONNECTING(r) \
103         (((r)->flags & DNS_REQUEST_F_CONNECTING) != 0)
104 #define DNS_REQUEST_SENDING(r) \
105         (((r)->flags & DNS_REQUEST_F_SENDING) != 0)
106 #define DNS_REQUEST_TIMEDOUT(r) \
107         (((r)->flags & DNS_REQUEST_F_TIMEDOUT) != 0)
108
109
110 /***
111  *** Forward
112  ***/
113
114 static void mgr_destroy(dns_requestmgr_t *requestmgr);
115 static void mgr_shutdown(dns_requestmgr_t *requestmgr);
116 static unsigned int mgr_gethash(dns_requestmgr_t *requestmgr);
117 static void send_shutdown_events(dns_requestmgr_t *requestmgr);
118
119 static isc_result_t req_render(dns_message_t *message, isc_buffer_t **buffer,
120                                unsigned int options, isc_mem_t *mctx);
121 static void req_senddone(isc_task_t *task, isc_event_t *event);
122 static void req_response(isc_task_t *task, isc_event_t *event);
123 static void req_timeout(isc_task_t *task, isc_event_t *event);
124 static isc_socket_t * req_getsocket(dns_request_t *request);
125 static void req_connected(isc_task_t *task, isc_event_t *event);
126 static void req_sendevent(dns_request_t *request, isc_result_t result);
127 static void req_cancel(dns_request_t *request);
128 static void req_destroy(dns_request_t *request);
129 static void req_log(int level, const char *fmt, ...) ISC_FORMAT_PRINTF(2, 3);
130 static void do_cancel(isc_task_t *task, isc_event_t *event);
131
132 /***
133  *** Public
134  ***/
135
136 isc_result_t
137 dns_requestmgr_create(isc_mem_t *mctx,
138                       isc_timermgr_t *timermgr,
139                       isc_socketmgr_t *socketmgr,
140                       isc_taskmgr_t *taskmgr,
141                       dns_dispatchmgr_t *dispatchmgr,
142                       dns_dispatch_t *dispatchv4,
143                       dns_dispatch_t *dispatchv6,
144                       dns_requestmgr_t **requestmgrp)
145 {
146         dns_requestmgr_t *requestmgr;
147         isc_socket_t *socket;
148         isc_result_t result;
149         int i;
150         unsigned int dispattr;
151
152         req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_create");
153
154         REQUIRE(requestmgrp != NULL && *requestmgrp == NULL);
155         REQUIRE(timermgr != NULL);
156         REQUIRE(socketmgr != NULL);
157         REQUIRE(taskmgr != NULL);
158         REQUIRE(dispatchmgr != NULL);
159         UNUSED(socket);
160         if (dispatchv4 != NULL) {
161                 dispattr = dns_dispatch_getattributes(dispatchv4);
162                 REQUIRE((dispattr & DNS_DISPATCHATTR_UDP) != 0);
163         }
164         if (dispatchv6 != NULL) {
165                 dispattr = dns_dispatch_getattributes(dispatchv6);
166                 REQUIRE((dispattr & DNS_DISPATCHATTR_UDP) != 0);
167         }
168
169         requestmgr = isc_mem_get(mctx, sizeof(*requestmgr));
170         if (requestmgr == NULL)
171                 return (ISC_R_NOMEMORY);
172
173         result = isc_mutex_init(&requestmgr->lock);
174         if (result != ISC_R_SUCCESS) {
175                 isc_mem_put(mctx, requestmgr, sizeof(*requestmgr));
176                 return (result);
177         }
178         for (i = 0; i < DNS_REQUEST_NLOCKS; i++) {
179                 result = isc_mutex_init(&requestmgr->locks[i]);
180                 if (result != ISC_R_SUCCESS) {
181                         while (--i >= 0)
182                                 DESTROYLOCK(&requestmgr->locks[i]);
183                         DESTROYLOCK(&requestmgr->lock);
184                         isc_mem_put(mctx, requestmgr, sizeof(*requestmgr));
185                         return (result);
186                 }
187         }
188         requestmgr->timermgr = timermgr;
189         requestmgr->socketmgr = socketmgr;
190         requestmgr->taskmgr = taskmgr;
191         requestmgr->dispatchmgr = dispatchmgr;
192         requestmgr->dispatchv4 = NULL;
193         if (dispatchv4 != NULL)
194                 dns_dispatch_attach(dispatchv4, &requestmgr->dispatchv4);
195         requestmgr->dispatchv6 = NULL;
196         if (dispatchv6 != NULL)
197                 dns_dispatch_attach(dispatchv6, &requestmgr->dispatchv6);
198         requestmgr->mctx = NULL;
199         isc_mem_attach(mctx, &requestmgr->mctx);
200         requestmgr->eref = 1;   /* implicit attach */
201         requestmgr->iref = 0;
202         ISC_LIST_INIT(requestmgr->whenshutdown);
203         ISC_LIST_INIT(requestmgr->requests);
204         requestmgr->exiting = ISC_FALSE;
205         requestmgr->hash = 0;
206         requestmgr->magic = REQUESTMGR_MAGIC;
207
208         req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_create: %p", requestmgr);
209
210         *requestmgrp = requestmgr;
211         return (ISC_R_SUCCESS);
212 }
213
214 void
215 dns_requestmgr_whenshutdown(dns_requestmgr_t *requestmgr, isc_task_t *task,
216                             isc_event_t **eventp)
217 {
218         isc_task_t *clone;
219         isc_event_t *event;
220
221         req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_whenshutdown");
222
223         REQUIRE(VALID_REQUESTMGR(requestmgr));
224         REQUIRE(eventp != NULL);
225
226         event = *eventp;
227         *eventp = NULL;
228
229         LOCK(&requestmgr->lock);
230
231         if (requestmgr->exiting) {
232                 /*
233                  * We're already shutdown.  Send the event.
234                  */
235                 event->ev_sender = requestmgr;
236                 isc_task_send(task, &event);
237         } else {
238                 clone = NULL;
239                 isc_task_attach(task, &clone);
240                 event->ev_sender = clone;
241                 ISC_LIST_APPEND(requestmgr->whenshutdown, event, ev_link);
242         }
243         UNLOCK(&requestmgr->lock);
244 }
245
246 void
247 dns_requestmgr_shutdown(dns_requestmgr_t *requestmgr) {
248
249         REQUIRE(VALID_REQUESTMGR(requestmgr));
250
251         req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_shutdown: %p", requestmgr);
252
253         LOCK(&requestmgr->lock);
254         mgr_shutdown(requestmgr);
255         UNLOCK(&requestmgr->lock);
256 }
257
258 static void
259 mgr_shutdown(dns_requestmgr_t *requestmgr) {
260         dns_request_t *request;
261
262         /*
263          * Caller holds lock.
264          */
265         if (!requestmgr->exiting) {
266                 requestmgr->exiting = ISC_TRUE;
267                 for (request = ISC_LIST_HEAD(requestmgr->requests);
268                      request != NULL;
269                      request = ISC_LIST_NEXT(request, link)) {
270                         dns_request_cancel(request);
271                 }
272                 if (requestmgr->iref == 0) {
273                         INSIST(ISC_LIST_EMPTY(requestmgr->requests));
274                         send_shutdown_events(requestmgr);
275                 }
276         }
277 }
278
279 static void
280 requestmgr_attach(dns_requestmgr_t *source, dns_requestmgr_t **targetp) {
281
282         /*
283          * Locked by caller.
284          */
285
286         REQUIRE(VALID_REQUESTMGR(source));
287         REQUIRE(targetp != NULL && *targetp == NULL);
288
289         REQUIRE(!source->exiting);
290
291         source->iref++;
292         *targetp = source;
293
294         req_log(ISC_LOG_DEBUG(3), "requestmgr_attach: %p: eref %d iref %d",
295                 source, source->eref, source->iref);
296 }
297
298 static void
299 requestmgr_detach(dns_requestmgr_t **requestmgrp) {
300         dns_requestmgr_t *requestmgr;
301         isc_boolean_t need_destroy = ISC_FALSE;
302
303         REQUIRE(requestmgrp != NULL);
304         requestmgr = *requestmgrp;
305         REQUIRE(VALID_REQUESTMGR(requestmgr));
306
307         *requestmgrp = NULL;
308         LOCK(&requestmgr->lock);
309         INSIST(requestmgr->iref > 0);
310         requestmgr->iref--;
311
312         req_log(ISC_LOG_DEBUG(3), "requestmgr_detach: %p: eref %d iref %d",
313                 requestmgr, requestmgr->eref, requestmgr->iref);
314
315         if (requestmgr->iref == 0 && requestmgr->exiting) {
316                 INSIST(ISC_LIST_HEAD(requestmgr->requests) == NULL);
317                 send_shutdown_events(requestmgr);
318                 if (requestmgr->eref == 0)
319                         need_destroy = ISC_TRUE;
320         }
321         UNLOCK(&requestmgr->lock);
322
323         if (need_destroy)
324                 mgr_destroy(requestmgr);
325 }
326
327 void
328 dns_requestmgr_attach(dns_requestmgr_t *source, dns_requestmgr_t **targetp) {
329
330         REQUIRE(VALID_REQUESTMGR(source));
331         REQUIRE(targetp != NULL && *targetp == NULL);
332         REQUIRE(!source->exiting);
333
334         LOCK(&source->lock);
335         source->eref++;
336         *targetp = source;
337         UNLOCK(&source->lock);
338
339         req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_attach: %p: eref %d iref %d",
340                 source, source->eref, source->iref);
341 }
342
343 void
344 dns_requestmgr_detach(dns_requestmgr_t **requestmgrp) {
345         dns_requestmgr_t *requestmgr;
346         isc_boolean_t need_destroy = ISC_FALSE;
347
348         REQUIRE(requestmgrp != NULL);
349         requestmgr = *requestmgrp;
350         REQUIRE(VALID_REQUESTMGR(requestmgr));
351
352         LOCK(&requestmgr->lock);
353         INSIST(requestmgr->eref > 0);
354         requestmgr->eref--;
355
356         req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_detach: %p: eref %d iref %d",
357                 requestmgr, requestmgr->eref, requestmgr->iref);
358
359         if (requestmgr->eref == 0 && requestmgr->iref == 0) {
360                 INSIST(requestmgr->exiting &&
361                        ISC_LIST_HEAD(requestmgr->requests) == NULL);
362                 need_destroy = ISC_TRUE;
363         }
364         UNLOCK(&requestmgr->lock);
365
366         if (need_destroy)
367                 mgr_destroy(requestmgr);
368
369         *requestmgrp = NULL;
370 }
371
372 static void
373 send_shutdown_events(dns_requestmgr_t *requestmgr) {
374         isc_event_t *event, *next_event;
375         isc_task_t *etask;
376
377         req_log(ISC_LOG_DEBUG(3), "send_shutdown_events: %p", requestmgr);
378
379         /*
380          * Caller must be holding the manager lock.
381          */
382         for (event = ISC_LIST_HEAD(requestmgr->whenshutdown);
383              event != NULL;
384              event = next_event) {
385                 next_event = ISC_LIST_NEXT(event, ev_link);
386                 ISC_LIST_UNLINK(requestmgr->whenshutdown, event, ev_link);
387                 etask = event->ev_sender;
388                 event->ev_sender = requestmgr;
389                 isc_task_sendanddetach(&etask, &event);
390         }
391 }
392
393 static void
394 mgr_destroy(dns_requestmgr_t *requestmgr) {
395         int i;
396         isc_mem_t *mctx;
397
398         req_log(ISC_LOG_DEBUG(3), "mgr_destroy");
399
400         REQUIRE(requestmgr->eref == 0);
401         REQUIRE(requestmgr->iref == 0);
402
403         DESTROYLOCK(&requestmgr->lock);
404         for (i = 0; i < DNS_REQUEST_NLOCKS; i++)
405                 DESTROYLOCK(&requestmgr->locks[i]);
406         if (requestmgr->dispatchv4 != NULL)
407                 dns_dispatch_detach(&requestmgr->dispatchv4);
408         if (requestmgr->dispatchv6 != NULL)
409                 dns_dispatch_detach(&requestmgr->dispatchv6);
410         requestmgr->magic = 0;
411         mctx = requestmgr->mctx;
412         isc_mem_put(mctx, requestmgr, sizeof(*requestmgr));
413         isc_mem_detach(&mctx);
414 }
415
416 static unsigned int
417 mgr_gethash(dns_requestmgr_t *requestmgr) {
418         req_log(ISC_LOG_DEBUG(3), "mgr_gethash");
419         /*
420          * Locked by caller.
421          */
422         requestmgr->hash++;
423         return (requestmgr->hash % DNS_REQUEST_NLOCKS);
424 }
425
426 static inline isc_result_t
427 req_send(dns_request_t *request, isc_task_t *task, isc_sockaddr_t *address) {
428         isc_region_t r;
429         isc_socket_t *socket;
430         isc_result_t result;
431         unsigned int dispattr;
432
433         req_log(ISC_LOG_DEBUG(3), "req_send: request %p", request);
434
435         REQUIRE(VALID_REQUEST(request));
436         dispattr = dns_dispatch_getattributes(request->dispatch);
437         socket = req_getsocket(request);
438         isc_buffer_usedregion(request->query, &r);
439         /*
440          * We could connect the socket when we are using an exclusive dispatch
441          * as we do in resolver.c, but we prefer implementation simplicity
442          * at this moment.
443          */
444         result = isc_socket_sendto(socket, &r, task, req_senddone,
445                                   request, address, NULL);
446         if (result == ISC_R_SUCCESS)
447                 request->flags |= DNS_REQUEST_F_SENDING;
448         return (result);
449 }
450
451 static isc_result_t
452 new_request(isc_mem_t *mctx, dns_request_t **requestp) {
453         dns_request_t *request;
454
455         request = isc_mem_get(mctx, sizeof(*request));
456         if (request == NULL)
457                 return (ISC_R_NOMEMORY);
458
459         /*
460          * Zero structure.
461          */
462         request->magic = 0;
463         request->mctx = NULL;
464         request->flags = 0;
465         ISC_LINK_INIT(request, link);
466         request->query = NULL;
467         request->answer = NULL;
468         request->event = NULL;
469         request->dispatch = NULL;
470         request->dispentry = NULL;
471         request->timer = NULL;
472         request->requestmgr = NULL;
473         request->tsig = NULL;
474         request->tsigkey = NULL;
475         ISC_EVENT_INIT(&request->ctlevent, sizeof(request->ctlevent), 0, NULL,
476                        DNS_EVENT_REQUESTCONTROL, do_cancel, request, NULL,
477                        NULL, NULL);
478         request->canceling = ISC_FALSE;
479         request->udpcount = 0;
480
481         isc_mem_attach(mctx, &request->mctx);
482
483         request->magic = REQUEST_MAGIC;
484         *requestp = request;
485         return (ISC_R_SUCCESS);
486 }
487
488
489 static isc_boolean_t
490 isblackholed(dns_dispatchmgr_t *dispatchmgr, isc_sockaddr_t *destaddr) {
491         dns_acl_t *blackhole;
492         isc_netaddr_t netaddr;
493         int match;
494         isc_boolean_t drop = ISC_FALSE;
495         char netaddrstr[ISC_NETADDR_FORMATSIZE];
496
497         blackhole = dns_dispatchmgr_getblackhole(dispatchmgr);
498         if (blackhole != NULL) {
499                 isc_netaddr_fromsockaddr(&netaddr, destaddr);
500                 if (dns_acl_match(&netaddr, NULL, blackhole,
501                                   NULL, &match, NULL) == ISC_R_SUCCESS &&
502                     match > 0)
503                         drop = ISC_TRUE;
504         }
505         if (drop) {
506                 isc_netaddr_format(&netaddr, netaddrstr, sizeof(netaddrstr));
507                 req_log(ISC_LOG_DEBUG(10), "blackholed address %s", netaddrstr);
508         }
509         return (drop);
510 }
511
512 static isc_result_t
513 create_tcp_dispatch(dns_requestmgr_t *requestmgr, isc_sockaddr_t *srcaddr,
514                     isc_sockaddr_t *destaddr, dns_dispatch_t **dispatchp)
515 {
516         isc_result_t result;
517         isc_socket_t *socket = NULL;
518         isc_sockaddr_t src;
519         unsigned int attrs;
520         isc_sockaddr_t bind_any;
521
522         result = isc_socket_create(requestmgr->socketmgr,
523                                    isc_sockaddr_pf(destaddr),
524                                    isc_sockettype_tcp, &socket);
525         if (result != ISC_R_SUCCESS)
526                 return (result);
527 #ifndef BROKEN_TCP_BIND_BEFORE_CONNECT
528         if (srcaddr == NULL) {
529                 isc_sockaddr_anyofpf(&bind_any,
530                                      isc_sockaddr_pf(destaddr));
531                 result = isc_socket_bind(socket, &bind_any, 0);
532         } else {
533                 src = *srcaddr;
534                 isc_sockaddr_setport(&src, 0);
535                 result = isc_socket_bind(socket, &src, 0);
536         }
537         if (result != ISC_R_SUCCESS)
538                 goto cleanup;
539 #endif
540         attrs = 0;
541         attrs |= DNS_DISPATCHATTR_TCP;
542         attrs |= DNS_DISPATCHATTR_PRIVATE;
543         if (isc_sockaddr_pf(destaddr) == AF_INET)
544                 attrs |= DNS_DISPATCHATTR_IPV4;
545         else
546                 attrs |= DNS_DISPATCHATTR_IPV6;
547         attrs |= DNS_DISPATCHATTR_MAKEQUERY;
548         result = dns_dispatch_createtcp(requestmgr->dispatchmgr,
549                                         socket, requestmgr->taskmgr,
550                                         4096, 2, 1, 1, 3, attrs,
551                                         dispatchp);
552 cleanup:
553         isc_socket_detach(&socket);
554         return (result);
555 }
556
557 static isc_result_t
558 find_udp_dispatch(dns_requestmgr_t *requestmgr, isc_sockaddr_t *srcaddr,
559                   isc_sockaddr_t *destaddr, dns_dispatch_t **dispatchp)
560 {
561         dns_dispatch_t *disp = NULL;
562         unsigned int attrs, attrmask;
563
564         if (srcaddr == NULL) {
565                 switch (isc_sockaddr_pf(destaddr)) {
566                 case PF_INET:
567                         disp = requestmgr->dispatchv4;
568                         break;
569
570                 case PF_INET6:
571                         disp = requestmgr->dispatchv6;
572                         break;
573
574                 default:
575                         return (ISC_R_NOTIMPLEMENTED);
576                 }
577                 if (disp == NULL)
578                         return (ISC_R_FAMILYNOSUPPORT);
579                 dns_dispatch_attach(disp, dispatchp);
580                 return (ISC_R_SUCCESS);
581         }
582         attrs = 0;
583         attrs |= DNS_DISPATCHATTR_UDP;
584         switch (isc_sockaddr_pf(srcaddr)) {
585         case PF_INET:
586                 attrs |= DNS_DISPATCHATTR_IPV4;
587                 break;
588
589         case PF_INET6:
590                 attrs |= DNS_DISPATCHATTR_IPV6;
591                 break;
592
593         default:
594                 return (ISC_R_NOTIMPLEMENTED);
595         }
596         attrmask = 0;
597         attrmask |= DNS_DISPATCHATTR_UDP;
598         attrmask |= DNS_DISPATCHATTR_TCP;
599         attrmask |= DNS_DISPATCHATTR_IPV4;
600         attrmask |= DNS_DISPATCHATTR_IPV6;
601         return (dns_dispatch_getudp(requestmgr->dispatchmgr,
602                                     requestmgr->socketmgr,
603                                     requestmgr->taskmgr,
604                                     srcaddr, 4096,
605                                     1000, 32768, 16411, 16433,
606                                     attrs, attrmask,
607                                     dispatchp));
608 }
609
610 static isc_result_t
611 get_dispatch(isc_boolean_t tcp, dns_requestmgr_t *requestmgr,
612              isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
613              dns_dispatch_t **dispatchp)
614 {
615         isc_result_t result;
616         if (tcp)
617                 result = create_tcp_dispatch(requestmgr, srcaddr,
618                                              destaddr, dispatchp);
619         else
620                 result = find_udp_dispatch(requestmgr, srcaddr,
621                                            destaddr, dispatchp);
622         return (result);
623 }
624
625 static isc_result_t
626 set_timer(isc_timer_t *timer, unsigned int timeout, unsigned int udpresend) {
627         isc_time_t expires;
628         isc_interval_t interval;
629         isc_result_t result;
630         isc_timertype_t timertype;
631
632         isc_interval_set(&interval, timeout, 0);
633         result = isc_time_nowplusinterval(&expires, &interval);
634         isc_interval_set(&interval, udpresend, 0);
635
636         timertype = udpresend != 0 ? isc_timertype_limited : isc_timertype_once;
637         if (result == ISC_R_SUCCESS)
638                 result = isc_timer_reset(timer, timertype, &expires,
639                                          &interval, ISC_FALSE);
640         return (result);
641 }
642
643 isc_result_t
644 dns_request_createraw(dns_requestmgr_t *requestmgr, isc_buffer_t *msgbuf,
645                       isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
646                       unsigned int options, unsigned int timeout,
647                       isc_task_t *task, isc_taskaction_t action, void *arg,
648                       dns_request_t **requestp)
649 {
650         return(dns_request_createraw3(requestmgr, msgbuf, srcaddr, destaddr,
651                                       options, timeout, 0, 0, task, action,
652                                       arg, requestp));
653 }
654
655 isc_result_t
656 dns_request_createraw2(dns_requestmgr_t *requestmgr, isc_buffer_t *msgbuf,
657                        isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
658                        unsigned int options, unsigned int timeout,
659                        unsigned int udptimeout, isc_task_t *task,
660                        isc_taskaction_t action, void *arg,
661                        dns_request_t **requestp)
662 {
663         unsigned int udpretries = 0;
664
665         if (udptimeout != 0)
666                 udpretries = timeout / udptimeout;
667
668         return (dns_request_createraw3(requestmgr, msgbuf, srcaddr, destaddr,
669                                        options, timeout, udptimeout,
670                                        udpretries, task, action, arg,
671                                        requestp));
672 }
673
674 isc_result_t
675 dns_request_createraw3(dns_requestmgr_t *requestmgr, isc_buffer_t *msgbuf,
676                        isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
677                        unsigned int options, unsigned int timeout,
678                        unsigned int udptimeout, unsigned int udpretries,
679                        isc_task_t *task, isc_taskaction_t action, void *arg,
680                        dns_request_t **requestp)
681 {
682         dns_request_t *request = NULL;
683         isc_task_t *tclone = NULL;
684         isc_socket_t *socket = NULL;
685         isc_result_t result;
686         isc_mem_t *mctx;
687         dns_messageid_t id;
688         isc_boolean_t tcp = ISC_FALSE;
689         isc_region_t r;
690
691         REQUIRE(VALID_REQUESTMGR(requestmgr));
692         REQUIRE(msgbuf != NULL);
693         REQUIRE(destaddr != NULL);
694         REQUIRE(task != NULL);
695         REQUIRE(action != NULL);
696         REQUIRE(requestp != NULL && *requestp == NULL);
697         REQUIRE(timeout > 0);
698         if (srcaddr != NULL)
699                 REQUIRE(isc_sockaddr_pf(srcaddr) == isc_sockaddr_pf(destaddr));
700
701         mctx = requestmgr->mctx;
702
703         req_log(ISC_LOG_DEBUG(3), "dns_request_createraw");
704
705         if (isblackholed(requestmgr->dispatchmgr, destaddr))
706                 return (DNS_R_BLACKHOLED);
707
708         request = NULL;
709         result = new_request(mctx, &request);
710         if (result != ISC_R_SUCCESS)
711                 return (result);
712
713         if (udptimeout == 0 && udpretries != 0) {
714                 udptimeout = timeout / (udpretries + 1);
715                 if (udptimeout == 0)
716                         udptimeout = 1;
717         }
718         request->udpcount = udpretries;
719
720         /*
721          * Create timer now.  We will set it below once.
722          */
723         result = isc_timer_create(requestmgr->timermgr, isc_timertype_inactive,
724                                   NULL, NULL, task, req_timeout, request,
725                                   &request->timer);
726         if (result != ISC_R_SUCCESS)
727                 goto cleanup;
728
729         request->event = (dns_requestevent_t *)
730                 isc_event_allocate(mctx, task, DNS_EVENT_REQUESTDONE,
731                                    action, arg, sizeof(dns_requestevent_t));
732         if (request->event == NULL) {
733                 result = ISC_R_NOMEMORY;
734                 goto cleanup;
735         }
736         isc_task_attach(task, &tclone);
737         request->event->ev_sender = task;
738         request->event->request = request;
739         request->event->result = ISC_R_FAILURE;
740
741         isc_buffer_usedregion(msgbuf, &r);
742         if (r.length < DNS_MESSAGE_HEADERLEN || r.length > 65535) {
743                 result = DNS_R_FORMERR;
744                 goto cleanup;
745         }
746
747         if ((options & DNS_REQUESTOPT_TCP) != 0 || r.length > 512)
748                 tcp = ISC_TRUE;
749
750         result = get_dispatch(tcp, requestmgr, srcaddr, destaddr,
751                               &request->dispatch);
752         if (result != ISC_R_SUCCESS)
753                 goto cleanup;
754
755         result = dns_dispatch_addresponse2(request->dispatch, destaddr, task,
756                                            req_response, request, &id,
757                                            &request->dispentry,
758                                            requestmgr->socketmgr);
759         if (result != ISC_R_SUCCESS)
760                 goto cleanup;
761
762         socket = req_getsocket(request);
763         INSIST(socket != NULL);
764
765         result = isc_buffer_allocate(mctx, &request->query,
766                                      r.length + (tcp ? 2 : 0));
767         if (result != ISC_R_SUCCESS)
768                 goto cleanup;
769         if (tcp)
770                 isc_buffer_putuint16(request->query, (isc_uint16_t)r.length);
771         result = isc_buffer_copyregion(request->query, &r);
772         if (result != ISC_R_SUCCESS)
773                 goto cleanup;
774
775         /* Add message ID. */
776         isc_buffer_usedregion(request->query, &r);
777         if (tcp)
778                 isc_region_consume(&r, 2);
779         r.base[0] = (id>>8) & 0xff;
780         r.base[1] = id & 0xff;
781
782         LOCK(&requestmgr->lock);
783         if (requestmgr->exiting) {
784                 UNLOCK(&requestmgr->lock);
785                 result = ISC_R_SHUTTINGDOWN;
786                 goto cleanup;
787         }
788         requestmgr_attach(requestmgr, &request->requestmgr);
789         request->hash = mgr_gethash(requestmgr);
790         ISC_LIST_APPEND(requestmgr->requests, request, link);
791         UNLOCK(&requestmgr->lock);
792
793         result = set_timer(request->timer, timeout, tcp ? 0 : udptimeout);
794         if (result != ISC_R_SUCCESS)
795                 goto unlink;
796
797         request->destaddr = *destaddr;
798         if (tcp) {
799                 result = isc_socket_connect(socket, destaddr, task,
800                                             req_connected, request);
801                 if (result != ISC_R_SUCCESS)
802                         goto unlink;
803                 request->flags |= DNS_REQUEST_F_CONNECTING|DNS_REQUEST_F_TCP;
804         } else {
805                 result = req_send(request, task, destaddr);
806                 if (result != ISC_R_SUCCESS)
807                         goto unlink;
808         }
809
810         req_log(ISC_LOG_DEBUG(3), "dns_request_createraw: request %p",
811                 request);
812         *requestp = request;
813         return (ISC_R_SUCCESS);
814
815  unlink:
816         LOCK(&requestmgr->lock);
817         ISC_LIST_UNLINK(requestmgr->requests, request, link);
818         UNLOCK(&requestmgr->lock);
819
820  cleanup:
821         if (tclone != NULL)
822                 isc_task_detach(&tclone);
823         req_destroy(request);
824         req_log(ISC_LOG_DEBUG(3), "dns_request_createraw: failed %s",
825                 dns_result_totext(result));
826         return (result);
827 }
828
829 isc_result_t
830 dns_request_create(dns_requestmgr_t *requestmgr, dns_message_t *message,
831                    isc_sockaddr_t *address, unsigned int options,
832                    dns_tsigkey_t *key,
833                    unsigned int timeout, isc_task_t *task,
834                    isc_taskaction_t action, void *arg,
835                    dns_request_t **requestp)
836 {
837         return (dns_request_createvia3(requestmgr, message, NULL, address,
838                                        options, key, timeout, 0, 0, task,
839                                        action, arg, requestp));
840 }
841
842 isc_result_t
843 dns_request_createvia(dns_requestmgr_t *requestmgr, dns_message_t *message,
844                       isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
845                       unsigned int options, dns_tsigkey_t *key,
846                       unsigned int timeout, isc_task_t *task,
847                       isc_taskaction_t action, void *arg,
848                       dns_request_t **requestp)
849 {
850         return(dns_request_createvia3(requestmgr, message, srcaddr, destaddr,
851                                       options, key, timeout, 0, 0, task,
852                                       action, arg, requestp));
853 }
854
855 isc_result_t
856 dns_request_createvia2(dns_requestmgr_t *requestmgr, dns_message_t *message,
857                        isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
858                        unsigned int options, dns_tsigkey_t *key,
859                        unsigned int timeout, unsigned int udptimeout,
860                        isc_task_t *task, isc_taskaction_t action, void *arg,
861                        dns_request_t **requestp)
862 {
863         unsigned int udpretries = 0;
864
865         if (udptimeout != 0)
866                 udpretries = timeout / udptimeout;
867         return (dns_request_createvia3(requestmgr, message, srcaddr, destaddr,
868                                        options, key, timeout, udptimeout,
869                                        udpretries, task, action, arg,
870                                        requestp));
871 }
872
873 isc_result_t
874 dns_request_createvia3(dns_requestmgr_t *requestmgr, dns_message_t *message,
875                        isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
876                        unsigned int options, dns_tsigkey_t *key,
877                        unsigned int timeout, unsigned int udptimeout,
878                        unsigned int udpretries, isc_task_t *task,
879                        isc_taskaction_t action, void *arg,
880                        dns_request_t **requestp)
881 {
882         dns_request_t *request = NULL;
883         isc_task_t *tclone = NULL;
884         isc_socket_t *socket = NULL;
885         isc_result_t result;
886         isc_mem_t *mctx;
887         dns_messageid_t id;
888         isc_boolean_t tcp;
889         isc_boolean_t setkey = ISC_TRUE;
890
891         REQUIRE(VALID_REQUESTMGR(requestmgr));
892         REQUIRE(message != NULL);
893         REQUIRE(destaddr != NULL);
894         REQUIRE(task != NULL);
895         REQUIRE(action != NULL);
896         REQUIRE(requestp != NULL && *requestp == NULL);
897         REQUIRE(timeout > 0);
898         if (srcaddr != NULL)
899                 REQUIRE(isc_sockaddr_pf(srcaddr) == isc_sockaddr_pf(destaddr));
900
901         mctx = requestmgr->mctx;
902
903         req_log(ISC_LOG_DEBUG(3), "dns_request_createvia");
904
905         if (isblackholed(requestmgr->dispatchmgr, destaddr))
906                 return (DNS_R_BLACKHOLED);
907
908         request = NULL;
909         result = new_request(mctx, &request);
910         if (result != ISC_R_SUCCESS)
911                 return (result);
912
913         if (udptimeout == 0 && udpretries != 0) {
914                 udptimeout = timeout / (udpretries + 1);
915                 if (udptimeout == 0)
916                         udptimeout = 1;
917         }
918         request->udpcount = udpretries;
919
920         /*
921          * Create timer now.  We will set it below once.
922          */
923         result = isc_timer_create(requestmgr->timermgr, isc_timertype_inactive,
924                                   NULL, NULL, task, req_timeout, request,
925                                   &request->timer);
926         if (result != ISC_R_SUCCESS)
927                 goto cleanup;
928
929         request->event = (dns_requestevent_t *)
930                 isc_event_allocate(mctx, task, DNS_EVENT_REQUESTDONE,
931                                    action, arg, sizeof(dns_requestevent_t));
932         if (request->event == NULL) {
933                 result = ISC_R_NOMEMORY;
934                 goto cleanup;
935         }
936         isc_task_attach(task, &tclone);
937         request->event->ev_sender = task;
938         request->event->request = request;
939         request->event->result = ISC_R_FAILURE;
940         if (key != NULL)
941                 dns_tsigkey_attach(key, &request->tsigkey);
942
943  use_tcp:
944         tcp = ISC_TF((options & DNS_REQUESTOPT_TCP) != 0);
945         result = get_dispatch(tcp, requestmgr, srcaddr, destaddr,
946                               &request->dispatch);
947         if (result != ISC_R_SUCCESS)
948                 goto cleanup;
949
950         result = dns_dispatch_addresponse2(request->dispatch, destaddr, task,
951                                            req_response, request, &id,
952                                            &request->dispentry,
953                                            requestmgr->socketmgr);
954         if (result != ISC_R_SUCCESS)
955                 goto cleanup;
956         socket = req_getsocket(request);
957         INSIST(socket != NULL);
958
959         message->id = id;
960         if (setkey) {
961                 result = dns_message_settsigkey(message, request->tsigkey);
962                 if (result != ISC_R_SUCCESS)
963                         goto cleanup;
964         }
965         result = req_render(message, &request->query, options, mctx);
966         if (result == DNS_R_USETCP &&
967             (options & DNS_REQUESTOPT_TCP) == 0) {
968                 /*
969                  * Try again using TCP.
970                  */
971                 dns_message_renderreset(message);
972                 dns_dispatch_removeresponse(&request->dispentry, NULL);
973                 dns_dispatch_detach(&request->dispatch);
974                 socket = NULL;
975                 options |= DNS_REQUESTOPT_TCP;
976                 setkey = ISC_FALSE;
977                 goto use_tcp;
978         }
979         if (result != ISC_R_SUCCESS)
980                 goto cleanup;
981
982         result = dns_message_getquerytsig(message, mctx, &request->tsig);
983         if (result != ISC_R_SUCCESS)
984                 goto cleanup;
985
986         LOCK(&requestmgr->lock);
987         if (requestmgr->exiting) {
988                 UNLOCK(&requestmgr->lock);
989                 result = ISC_R_SHUTTINGDOWN;
990                 goto cleanup;
991         }
992         requestmgr_attach(requestmgr, &request->requestmgr);
993         request->hash = mgr_gethash(requestmgr);
994         ISC_LIST_APPEND(requestmgr->requests, request, link);
995         UNLOCK(&requestmgr->lock);
996
997         result = set_timer(request->timer, timeout, tcp ? 0 : udptimeout);
998         if (result != ISC_R_SUCCESS)
999                 goto unlink;
1000
1001         request->destaddr = *destaddr;
1002         if (tcp) {
1003                 result = isc_socket_connect(socket, destaddr, task,
1004                                             req_connected, request);
1005                 if (result != ISC_R_SUCCESS)
1006                         goto unlink;
1007                 request->flags |= DNS_REQUEST_F_CONNECTING|DNS_REQUEST_F_TCP;
1008         } else {
1009                 result = req_send(request, task, destaddr);
1010                 if (result != ISC_R_SUCCESS)
1011                         goto unlink;
1012         }
1013
1014         req_log(ISC_LOG_DEBUG(3), "dns_request_createvia: request %p",
1015                 request);
1016         *requestp = request;
1017         return (ISC_R_SUCCESS);
1018
1019  unlink:
1020         LOCK(&requestmgr->lock);
1021         ISC_LIST_UNLINK(requestmgr->requests, request, link);
1022         UNLOCK(&requestmgr->lock);
1023
1024  cleanup:
1025         if (tclone != NULL)
1026                 isc_task_detach(&tclone);
1027         req_destroy(request);
1028         req_log(ISC_LOG_DEBUG(3), "dns_request_createvia: failed %s",
1029                 dns_result_totext(result));
1030         return (result);
1031 }
1032
1033 static isc_result_t
1034 req_render(dns_message_t *message, isc_buffer_t **bufferp,
1035            unsigned int options, isc_mem_t *mctx)
1036 {
1037         isc_buffer_t *buf1 = NULL;
1038         isc_buffer_t *buf2 = NULL;
1039         isc_result_t result;
1040         isc_region_t r;
1041         isc_boolean_t tcp = ISC_FALSE;
1042         dns_compress_t cctx;
1043         isc_boolean_t cleanup_cctx = ISC_FALSE;
1044
1045         REQUIRE(bufferp != NULL && *bufferp == NULL);
1046
1047         req_log(ISC_LOG_DEBUG(3), "request_render");
1048
1049         /*
1050          * Create buffer able to hold largest possible message.
1051          */
1052         result = isc_buffer_allocate(mctx, &buf1, 65535);
1053         if (result != ISC_R_SUCCESS)
1054                 return (result);
1055
1056         result = dns_compress_init(&cctx, -1, mctx);
1057         if (result != ISC_R_SUCCESS)
1058                 return (result);
1059         cleanup_cctx = ISC_TRUE;
1060
1061         /*
1062          * Render message.
1063          */
1064         result = dns_message_renderbegin(message, &cctx, buf1);
1065         if (result != ISC_R_SUCCESS)
1066                 goto cleanup;
1067         result = dns_message_rendersection(message, DNS_SECTION_QUESTION, 0);
1068         if (result != ISC_R_SUCCESS)
1069                 goto cleanup;
1070         result = dns_message_rendersection(message, DNS_SECTION_ANSWER, 0);
1071         if (result != ISC_R_SUCCESS)
1072                 goto cleanup;
1073         result = dns_message_rendersection(message, DNS_SECTION_AUTHORITY, 0);
1074         if (result != ISC_R_SUCCESS)
1075                 goto cleanup;
1076         result = dns_message_rendersection(message, DNS_SECTION_ADDITIONAL, 0);
1077         if (result != ISC_R_SUCCESS)
1078                 goto cleanup;
1079         result = dns_message_renderend(message);
1080         if (result != ISC_R_SUCCESS)
1081                 goto cleanup;
1082
1083         dns_compress_invalidate(&cctx);
1084         cleanup_cctx = ISC_FALSE;
1085
1086         /*
1087          * Copy rendered message to exact sized buffer.
1088          */
1089         isc_buffer_usedregion(buf1, &r);
1090         if ((options & DNS_REQUESTOPT_TCP) != 0) {
1091                 tcp = ISC_TRUE;
1092         } else if (r.length > 512) {
1093                 result = DNS_R_USETCP;
1094                 goto cleanup;
1095         }
1096         result = isc_buffer_allocate(mctx, &buf2, r.length + (tcp ? 2 : 0));
1097         if (result != ISC_R_SUCCESS)
1098                 goto cleanup;
1099         if (tcp)
1100                 isc_buffer_putuint16(buf2, (isc_uint16_t)r.length);
1101         result = isc_buffer_copyregion(buf2, &r);
1102         if (result != ISC_R_SUCCESS)
1103                 goto cleanup;
1104
1105         /*
1106          * Cleanup and return.
1107          */
1108         isc_buffer_free(&buf1);
1109         *bufferp = buf2;
1110         return (ISC_R_SUCCESS);
1111
1112  cleanup:
1113         dns_message_renderreset(message);
1114         if (buf1 != NULL)
1115                 isc_buffer_free(&buf1);
1116         if (buf2 != NULL)
1117                 isc_buffer_free(&buf2);
1118         if (cleanup_cctx)
1119                 dns_compress_invalidate(&cctx);
1120         return (result);
1121 }
1122
1123
1124 /*
1125  * If this request is no longer waiting for events,
1126  * send the completion event.  This will ultimately
1127  * cause the request to be destroyed.
1128  *
1129  * Requires:
1130  *      'request' is locked by the caller.
1131  */
1132 static void
1133 send_if_done(dns_request_t *request, isc_result_t result) {
1134         if (!DNS_REQUEST_CONNECTING(request) &&
1135             !DNS_REQUEST_SENDING(request) &&
1136             !request->canceling)
1137                 req_sendevent(request, result);
1138 }
1139
1140 /*
1141  * Handle the control event.
1142  */
1143 static void
1144 do_cancel(isc_task_t *task, isc_event_t *event) {
1145         dns_request_t *request = event->ev_arg;
1146         UNUSED(task);
1147         INSIST(event->ev_type == DNS_EVENT_REQUESTCONTROL);
1148         LOCK(&request->requestmgr->locks[request->hash]);
1149         request->canceling = ISC_FALSE;
1150         if (!DNS_REQUEST_CANCELED(request))
1151                 req_cancel(request);
1152         send_if_done(request, ISC_R_CANCELED);
1153         UNLOCK(&request->requestmgr->locks[request->hash]);
1154 }
1155
1156 void
1157 dns_request_cancel(dns_request_t *request) {
1158         REQUIRE(VALID_REQUEST(request));
1159
1160         req_log(ISC_LOG_DEBUG(3), "dns_request_cancel: request %p", request);
1161
1162         REQUIRE(VALID_REQUEST(request));
1163
1164         LOCK(&request->requestmgr->locks[request->hash]);
1165         if (!request->canceling && !DNS_REQUEST_CANCELED(request)) {
1166                 isc_event_t *ev =  &request->ctlevent;
1167                 isc_task_send(request->event->ev_sender, &ev);
1168                 request->canceling = ISC_TRUE;
1169         }
1170         UNLOCK(&request->requestmgr->locks[request->hash]);
1171 }
1172
1173 isc_result_t
1174 dns_request_getresponse(dns_request_t *request, dns_message_t *message,
1175                         unsigned int options)
1176 {
1177         isc_result_t result;
1178
1179         REQUIRE(VALID_REQUEST(request));
1180         REQUIRE(request->answer != NULL);
1181
1182         req_log(ISC_LOG_DEBUG(3), "dns_request_getresponse: request %p",
1183                 request);
1184
1185         result = dns_message_setquerytsig(message, request->tsig);
1186         if (result != ISC_R_SUCCESS)
1187                 return (result);
1188         result = dns_message_settsigkey(message, request->tsigkey);
1189         if (result != ISC_R_SUCCESS)
1190                 return (result);
1191         result = dns_message_parse(message, request->answer, options);
1192         if (result != ISC_R_SUCCESS)
1193                 return (result);
1194         if (request->tsigkey != NULL)
1195                 result = dns_tsig_verify(request->answer, message, NULL, NULL);
1196         return (result);
1197 }
1198
1199 isc_boolean_t
1200 dns_request_usedtcp(dns_request_t *request) {
1201         REQUIRE(VALID_REQUEST(request));
1202
1203         return (ISC_TF((request->flags & DNS_REQUEST_F_TCP) != 0));
1204 }
1205
1206 void
1207 dns_request_destroy(dns_request_t **requestp) {
1208         dns_request_t *request;
1209
1210         REQUIRE(requestp != NULL && VALID_REQUEST(*requestp));
1211
1212         request = *requestp;
1213
1214         req_log(ISC_LOG_DEBUG(3), "dns_request_destroy: request %p", request);
1215
1216         LOCK(&request->requestmgr->lock);
1217         LOCK(&request->requestmgr->locks[request->hash]);
1218         ISC_LIST_UNLINK(request->requestmgr->requests, request, link);
1219         INSIST(!DNS_REQUEST_CONNECTING(request));
1220         INSIST(!DNS_REQUEST_SENDING(request));
1221         UNLOCK(&request->requestmgr->locks[request->hash]);
1222         UNLOCK(&request->requestmgr->lock);
1223
1224         /*
1225          * These should have been cleaned up by req_cancel() before
1226          * the completion event was sent.
1227          */
1228         INSIST(!ISC_LINK_LINKED(request, link));
1229         INSIST(request->dispentry == NULL);
1230         INSIST(request->dispatch == NULL);
1231         INSIST(request->timer == NULL);
1232
1233         req_destroy(request);
1234
1235         *requestp = NULL;
1236 }
1237
1238 /***
1239  *** Private: request.
1240  ***/
1241
1242 static isc_socket_t *
1243 req_getsocket(dns_request_t *request) {
1244         unsigned int dispattr;
1245         isc_socket_t *socket;
1246
1247         dispattr = dns_dispatch_getattributes(request->dispatch);
1248         if ((dispattr & DNS_DISPATCHATTR_EXCLUSIVE) != 0) {
1249                 INSIST(request->dispentry != NULL);
1250                 socket = dns_dispatch_getentrysocket(request->dispentry);
1251         } else
1252                 socket = dns_dispatch_getsocket(request->dispatch);
1253
1254         return (socket);
1255 }
1256
1257 static void
1258 req_connected(isc_task_t *task, isc_event_t *event) {
1259         isc_socketevent_t *sevent = (isc_socketevent_t *)event;
1260         isc_result_t result;
1261         dns_request_t *request = event->ev_arg;
1262
1263         REQUIRE(event->ev_type == ISC_SOCKEVENT_CONNECT);
1264         REQUIRE(VALID_REQUEST(request));
1265         REQUIRE(DNS_REQUEST_CONNECTING(request));
1266
1267         req_log(ISC_LOG_DEBUG(3), "req_connected: request %p", request);
1268
1269         LOCK(&request->requestmgr->locks[request->hash]);
1270         request->flags &= ~DNS_REQUEST_F_CONNECTING;
1271
1272         if (DNS_REQUEST_CANCELED(request)) {
1273                 /*
1274                  * Send delayed event.
1275                  */
1276                 if (DNS_REQUEST_TIMEDOUT(request))
1277                         send_if_done(request, ISC_R_TIMEDOUT);
1278                 else
1279                         send_if_done(request, ISC_R_CANCELED);
1280         } else {
1281                 dns_dispatch_starttcp(request->dispatch);
1282                 result = sevent->result;
1283                 if (result == ISC_R_SUCCESS)
1284                         result = req_send(request, task, NULL);
1285
1286                 if (result != ISC_R_SUCCESS) {
1287                         req_cancel(request);
1288                         send_if_done(request, ISC_R_CANCELED);
1289                 }
1290         }
1291         UNLOCK(&request->requestmgr->locks[request->hash]);
1292         isc_event_free(&event);
1293 }
1294
1295 static void
1296 req_senddone(isc_task_t *task, isc_event_t *event) {
1297         isc_socketevent_t *sevent = (isc_socketevent_t *)event;
1298         dns_request_t *request = event->ev_arg;
1299
1300         REQUIRE(event->ev_type == ISC_SOCKEVENT_SENDDONE);
1301         REQUIRE(VALID_REQUEST(request));
1302         REQUIRE(DNS_REQUEST_SENDING(request));
1303
1304         req_log(ISC_LOG_DEBUG(3), "req_senddone: request %p", request);
1305
1306         UNUSED(task);
1307
1308         LOCK(&request->requestmgr->locks[request->hash]);
1309         request->flags &= ~DNS_REQUEST_F_SENDING;
1310
1311         if (DNS_REQUEST_CANCELED(request)) {
1312                 /*
1313                  * Send delayed event.
1314                  */
1315                 if (DNS_REQUEST_TIMEDOUT(request))
1316                         send_if_done(request, ISC_R_TIMEDOUT);
1317                 else
1318                         send_if_done(request, ISC_R_CANCELED);
1319         } else if (sevent->result != ISC_R_SUCCESS) {
1320                         req_cancel(request);
1321                         send_if_done(request, ISC_R_CANCELED);
1322         }
1323         UNLOCK(&request->requestmgr->locks[request->hash]);
1324
1325         isc_event_free(&event);
1326 }
1327
1328 static void
1329 req_response(isc_task_t *task, isc_event_t *event) {
1330         isc_result_t result;
1331         dns_request_t *request = event->ev_arg;
1332         dns_dispatchevent_t *devent = (dns_dispatchevent_t *)event;
1333         isc_region_t r;
1334
1335         REQUIRE(VALID_REQUEST(request));
1336         REQUIRE(event->ev_type == DNS_EVENT_DISPATCH);
1337
1338         UNUSED(task);
1339
1340         req_log(ISC_LOG_DEBUG(3), "req_response: request %p: %s", request,
1341                 dns_result_totext(devent->result));
1342
1343         LOCK(&request->requestmgr->locks[request->hash]);
1344         result = devent->result;
1345         if (result != ISC_R_SUCCESS)
1346                 goto done;
1347
1348         /*
1349          * Copy buffer to request.
1350          */
1351         isc_buffer_usedregion(&devent->buffer, &r);
1352         result = isc_buffer_allocate(request->mctx, &request->answer,
1353                                      r.length);
1354         if (result != ISC_R_SUCCESS)
1355                 goto done;
1356         result = isc_buffer_copyregion(request->answer, &r);
1357         if (result != ISC_R_SUCCESS)
1358                 isc_buffer_free(&request->answer);
1359  done:
1360         /*
1361          * Cleanup.
1362          */
1363         dns_dispatch_removeresponse(&request->dispentry, &devent);
1364         req_cancel(request);
1365         /*
1366          * Send completion event.
1367          */
1368         send_if_done(request, result);
1369         UNLOCK(&request->requestmgr->locks[request->hash]);
1370 }
1371
1372 static void
1373 req_timeout(isc_task_t *task, isc_event_t *event) {
1374         dns_request_t *request = event->ev_arg;
1375         isc_result_t result;
1376
1377         REQUIRE(VALID_REQUEST(request));
1378
1379         req_log(ISC_LOG_DEBUG(3), "req_timeout: request %p", request);
1380
1381         UNUSED(task);
1382         LOCK(&request->requestmgr->locks[request->hash]);
1383         if (event->ev_type == ISC_TIMEREVENT_TICK &&
1384             request->udpcount-- != 0) {
1385                 if (! DNS_REQUEST_SENDING(request)) {
1386                         result = req_send(request, task, &request->destaddr);
1387                         if (result != ISC_R_SUCCESS) {
1388                                 req_cancel(request);
1389                                 send_if_done(request, result);
1390                         }
1391                 }
1392         } else {
1393                 request->flags |= DNS_REQUEST_F_TIMEDOUT;
1394                 req_cancel(request);
1395                 send_if_done(request, ISC_R_TIMEDOUT);
1396         }
1397         UNLOCK(&request->requestmgr->locks[request->hash]);
1398         isc_event_free(&event);
1399 }
1400
1401 static void
1402 req_sendevent(dns_request_t *request, isc_result_t result) {
1403         isc_task_t *task;
1404
1405         REQUIRE(VALID_REQUEST(request));
1406
1407         req_log(ISC_LOG_DEBUG(3), "req_sendevent: request %p", request);
1408
1409         /*
1410          * Lock held by caller.
1411          */
1412         task = request->event->ev_sender;
1413         request->event->ev_sender = request;
1414         request->event->result = result;
1415         isc_task_sendanddetach(&task, (isc_event_t **)&request->event);
1416 }
1417
1418 static void
1419 req_destroy(dns_request_t *request) {
1420         isc_mem_t *mctx;
1421
1422         REQUIRE(VALID_REQUEST(request));
1423
1424         req_log(ISC_LOG_DEBUG(3), "req_destroy: request %p", request);
1425
1426         request->magic = 0;
1427         if (request->query != NULL)
1428                 isc_buffer_free(&request->query);
1429         if (request->answer != NULL)
1430                 isc_buffer_free(&request->answer);
1431         if (request->event != NULL)
1432                 isc_event_free((isc_event_t **)&request->event);
1433         if (request->dispentry != NULL)
1434                 dns_dispatch_removeresponse(&request->dispentry, NULL);
1435         if (request->dispatch != NULL)
1436                 dns_dispatch_detach(&request->dispatch);
1437         if (request->timer != NULL)
1438                 isc_timer_detach(&request->timer);
1439         if (request->tsig != NULL)
1440                 isc_buffer_free(&request->tsig);
1441         if (request->tsigkey != NULL)
1442                 dns_tsigkey_detach(&request->tsigkey);
1443         if (request->requestmgr != NULL)
1444                 requestmgr_detach(&request->requestmgr);
1445         mctx = request->mctx;
1446         isc_mem_put(mctx, request, sizeof(*request));
1447         isc_mem_detach(&mctx);
1448 }
1449
1450 /*
1451  * Stop the current request.  Must be called from the request's task.
1452  */
1453 static void
1454 req_cancel(dns_request_t *request) {
1455         isc_socket_t *socket;
1456         unsigned int dispattr;
1457
1458         REQUIRE(VALID_REQUEST(request));
1459
1460         req_log(ISC_LOG_DEBUG(3), "req_cancel: request %p", request);
1461
1462         /*
1463          * Lock held by caller.
1464          */
1465         request->flags |= DNS_REQUEST_F_CANCELED;
1466
1467         if (request->timer != NULL)
1468                 isc_timer_detach(&request->timer);
1469         dispattr = dns_dispatch_getattributes(request->dispatch);
1470         socket = NULL;
1471         if (DNS_REQUEST_CONNECTING(request) || DNS_REQUEST_SENDING(request)) {
1472                 if ((dispattr & DNS_DISPATCHATTR_EXCLUSIVE) != 0) {
1473                         if (request->dispentry != NULL) {
1474                                 socket = dns_dispatch_getentrysocket(
1475                                         request->dispentry);
1476                         }
1477                 } else
1478                         socket = dns_dispatch_getsocket(request->dispatch);
1479                 if (DNS_REQUEST_CONNECTING(request) && socket != NULL)
1480                         isc_socket_cancel(socket, NULL, ISC_SOCKCANCEL_CONNECT);
1481                 if (DNS_REQUEST_SENDING(request) && socket != NULL)
1482                         isc_socket_cancel(socket, NULL, ISC_SOCKCANCEL_SEND);
1483         }
1484         if (request->dispentry != NULL)
1485                 dns_dispatch_removeresponse(&request->dispentry, NULL);
1486         dns_dispatch_detach(&request->dispatch);
1487 }
1488
1489 static void
1490 req_log(int level, const char *fmt, ...) {
1491         va_list ap;
1492
1493         va_start(ap, fmt);
1494         isc_log_vwrite(dns_lctx, DNS_LOGCATEGORY_GENERAL,
1495                        DNS_LOGMODULE_REQUEST, level, fmt, ap);
1496         va_end(ap);
1497 }