contrib/bind9/lib/dns/request.c

   1 /*
   2  * Copyright (C) 2004-2009, 2011  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 1.82.72.4 2011-03-12 04:57:27 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
 432         req_log(ISC_LOG_DEBUG(3), "req_send: request %p", request);
 433
 434         REQUIRE(VALID_REQUEST(request));
 435         socket = req_getsocket(request);
 436         isc_buffer_usedregion(request->query, &r);
 437         /*
 438          * We could connect the socket when we are using an exclusive dispatch
 439          * as we do in resolver.c, but we prefer implementation simplicity
 440          * at this moment.
 441          */
 442         result = isc_socket_sendto(socket, &r, task, req_senddone,
 443                                   request, address, NULL);
 444         if (result == ISC_R_SUCCESS)
 445                 request->flags |= DNS_REQUEST_F_SENDING;
 446         return (result);
 447 }
 448
 449 static isc_result_t
 450 new_request(isc_mem_t *mctx, dns_request_t **requestp) {
 451         dns_request_t *request;
 452
 453         request = isc_mem_get(mctx, sizeof(*request));
 454         if (request == NULL)
 455                 return (ISC_R_NOMEMORY);
 456
 457         /*
 458          * Zero structure.
 459          */
 460         request->magic = 0;
 461         request->mctx = NULL;
 462         request->flags = 0;
 463         ISC_LINK_INIT(request, link);
 464         request->query = NULL;
 465         request->answer = NULL;
 466         request->event = NULL;
 467         request->dispatch = NULL;
 468         request->dispentry = NULL;
 469         request->timer = NULL;
 470         request->requestmgr = NULL;
 471         request->tsig = NULL;
 472         request->tsigkey = NULL;
 473         ISC_EVENT_INIT(&request->ctlevent, sizeof(request->ctlevent), 0, NULL,
 474                        DNS_EVENT_REQUESTCONTROL, do_cancel, request, NULL,
 475                        NULL, NULL);
 476         request->canceling = ISC_FALSE;
 477         request->udpcount = 0;
 478
 479         isc_mem_attach(mctx, &request->mctx);
 480
 481         request->magic = REQUEST_MAGIC;
 482         *requestp = request;
 483         return (ISC_R_SUCCESS);
 484 }
 485
 486
 487 static isc_boolean_t
 488 isblackholed(dns_dispatchmgr_t *dispatchmgr, isc_sockaddr_t *destaddr) {
 489         dns_acl_t *blackhole;
 490         isc_netaddr_t netaddr;
 491         int match;
 492         isc_boolean_t drop = ISC_FALSE;
 493         char netaddrstr[ISC_NETADDR_FORMATSIZE];
 494
 495         blackhole = dns_dispatchmgr_getblackhole(dispatchmgr);
 496         if (blackhole != NULL) {
 497                 isc_netaddr_fromsockaddr(&netaddr, destaddr);
 498                 if (dns_acl_match(&netaddr, NULL, blackhole,
 499                                   NULL, &match, NULL) == ISC_R_SUCCESS &&
 500                     match > 0)
 501                         drop = ISC_TRUE;
 502         }
 503         if (drop) {
 504                 isc_netaddr_format(&netaddr, netaddrstr, sizeof(netaddrstr));
 505                 req_log(ISC_LOG_DEBUG(10), "blackholed address %s", netaddrstr);
 506         }
 507         return (drop);
 508 }
 509
 510 static isc_result_t
 511 create_tcp_dispatch(dns_requestmgr_t *requestmgr, isc_sockaddr_t *srcaddr,
 512                     isc_sockaddr_t *destaddr, dns_dispatch_t **dispatchp)
 513 {
 514         isc_result_t result;
 515         isc_socket_t *socket = NULL;
 516         isc_sockaddr_t src;
 517         unsigned int attrs;
 518         isc_sockaddr_t bind_any;
 519
 520         result = isc_socket_create(requestmgr->socketmgr,
 521                                    isc_sockaddr_pf(destaddr),
 522                                    isc_sockettype_tcp, &socket);
 523         if (result != ISC_R_SUCCESS)
 524                 return (result);
 525 #ifndef BROKEN_TCP_BIND_BEFORE_CONNECT
 526         if (srcaddr == NULL) {
 527                 isc_sockaddr_anyofpf(&bind_any,
 528                                      isc_sockaddr_pf(destaddr));
 529                 result = isc_socket_bind(socket, &bind_any, 0);
 530         } else {
 531                 src = *srcaddr;
 532                 isc_sockaddr_setport(&src, 0);
 533                 result = isc_socket_bind(socket, &src, 0);
 534         }
 535         if (result != ISC_R_SUCCESS)
 536                 goto cleanup;
 537 #endif
 538         attrs = 0;
 539         attrs |= DNS_DISPATCHATTR_TCP;
 540         attrs |= DNS_DISPATCHATTR_PRIVATE;
 541         if (isc_sockaddr_pf(destaddr) == AF_INET)
 542                 attrs |= DNS_DISPATCHATTR_IPV4;
 543         else
 544                 attrs |= DNS_DISPATCHATTR_IPV6;
 545         attrs |= DNS_DISPATCHATTR_MAKEQUERY;
 546         result = dns_dispatch_createtcp(requestmgr->dispatchmgr,
 547                                         socket, requestmgr->taskmgr,
 548                                         4096, 2, 1, 1, 3, attrs,
 549                                         dispatchp);
 550 cleanup:
 551         isc_socket_detach(&socket);
 552         return (result);
 553 }
 554
 555 static isc_result_t
 556 find_udp_dispatch(dns_requestmgr_t *requestmgr, isc_sockaddr_t *srcaddr,
 557                   isc_sockaddr_t *destaddr, dns_dispatch_t **dispatchp)
 558 {
 559         dns_dispatch_t *disp = NULL;
 560         unsigned int attrs, attrmask;
 561
 562         if (srcaddr == NULL) {
 563                 switch (isc_sockaddr_pf(destaddr)) {
 564                 case PF_INET:
 565                         disp = requestmgr->dispatchv4;
 566                         break;
 567
 568                 case PF_INET6:
 569                         disp = requestmgr->dispatchv6;
 570                         break;
 571
 572                 default:
 573                         return (ISC_R_NOTIMPLEMENTED);
 574                 }
 575                 if (disp == NULL)
 576                         return (ISC_R_FAMILYNOSUPPORT);
 577                 dns_dispatch_attach(disp, dispatchp);
 578                 return (ISC_R_SUCCESS);
 579         }
 580         attrs = 0;
 581         attrs |= DNS_DISPATCHATTR_UDP;
 582         switch (isc_sockaddr_pf(srcaddr)) {
 583         case PF_INET:
 584                 attrs |= DNS_DISPATCHATTR_IPV4;
 585                 break;
 586
 587         case PF_INET6:
 588                 attrs |= DNS_DISPATCHATTR_IPV6;
 589                 break;
 590
 591         default:
 592                 return (ISC_R_NOTIMPLEMENTED);
 593         }
 594         attrmask = 0;
 595         attrmask |= DNS_DISPATCHATTR_UDP;
 596         attrmask |= DNS_DISPATCHATTR_TCP;
 597         attrmask |= DNS_DISPATCHATTR_IPV4;
 598         attrmask |= DNS_DISPATCHATTR_IPV6;
 599         return (dns_dispatch_getudp(requestmgr->dispatchmgr,
 600                                     requestmgr->socketmgr,
 601                                     requestmgr->taskmgr,
 602                                     srcaddr, 4096,
 603                                     1000, 32768, 16411, 16433,
 604                                     attrs, attrmask,
 605                                     dispatchp));
 606 }
 607
 608 static isc_result_t
 609 get_dispatch(isc_boolean_t tcp, dns_requestmgr_t *requestmgr,
 610              isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 611              dns_dispatch_t **dispatchp)
 612 {
 613         isc_result_t result;
 614         if (tcp)
 615                 result = create_tcp_dispatch(requestmgr, srcaddr,
 616                                              destaddr, dispatchp);
 617         else
 618                 result = find_udp_dispatch(requestmgr, srcaddr,
 619                                            destaddr, dispatchp);
 620         return (result);
 621 }
 622
 623 static isc_result_t
 624 set_timer(isc_timer_t *timer, unsigned int timeout, unsigned int udpresend) {
 625         isc_time_t expires;
 626         isc_interval_t interval;
 627         isc_result_t result;
 628         isc_timertype_t timertype;
 629
 630         isc_interval_set(&interval, timeout, 0);
 631         result = isc_time_nowplusinterval(&expires, &interval);
 632         isc_interval_set(&interval, udpresend, 0);
 633
 634         timertype = udpresend != 0 ? isc_timertype_limited : isc_timertype_once;
 635         if (result == ISC_R_SUCCESS)
 636                 result = isc_timer_reset(timer, timertype, &expires,
 637                                          &interval, ISC_FALSE);
 638         return (result);
 639 }
 640
 641 isc_result_t
 642 dns_request_createraw(dns_requestmgr_t *requestmgr, isc_buffer_t *msgbuf,
 643                       isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 644                       unsigned int options, unsigned int timeout,
 645                       isc_task_t *task, isc_taskaction_t action, void *arg,
 646                       dns_request_t **requestp)
 647 {
 648         return(dns_request_createraw3(requestmgr, msgbuf, srcaddr, destaddr,
 649                                       options, timeout, 0, 0, task, action,
 650                                       arg, requestp));
 651 }
 652
 653 isc_result_t
 654 dns_request_createraw2(dns_requestmgr_t *requestmgr, isc_buffer_t *msgbuf,
 655                        isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 656                        unsigned int options, unsigned int timeout,
 657                        unsigned int udptimeout, isc_task_t *task,
 658                        isc_taskaction_t action, void *arg,
 659                        dns_request_t **requestp)
 660 {
 661         unsigned int udpretries = 0;
 662
 663         if (udptimeout != 0)
 664                 udpretries = timeout / udptimeout;
 665
 666         return (dns_request_createraw3(requestmgr, msgbuf, srcaddr, destaddr,
 667                                        options, timeout, udptimeout,
 668                                        udpretries, task, action, arg,
 669                                        requestp));
 670 }
 671
 672 isc_result_t
 673 dns_request_createraw3(dns_requestmgr_t *requestmgr, isc_buffer_t *msgbuf,
 674                        isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 675                        unsigned int options, unsigned int timeout,
 676                        unsigned int udptimeout, unsigned int udpretries,
 677                        isc_task_t *task, isc_taskaction_t action, void *arg,
 678                        dns_request_t **requestp)
 679 {
 680         dns_request_t *request = NULL;
 681         isc_task_t *tclone = NULL;
 682         isc_socket_t *socket = NULL;
 683         isc_result_t result;
 684         isc_mem_t *mctx;
 685         dns_messageid_t id;
 686         isc_boolean_t tcp = ISC_FALSE;
 687         isc_region_t r;
 688
 689         REQUIRE(VALID_REQUESTMGR(requestmgr));
 690         REQUIRE(msgbuf != NULL);
 691         REQUIRE(destaddr != NULL);
 692         REQUIRE(task != NULL);
 693         REQUIRE(action != NULL);
 694         REQUIRE(requestp != NULL && *requestp == NULL);
 695         REQUIRE(timeout > 0);
 696         if (srcaddr != NULL)
 697                 REQUIRE(isc_sockaddr_pf(srcaddr) == isc_sockaddr_pf(destaddr));
 698
 699         mctx = requestmgr->mctx;
 700
 701         req_log(ISC_LOG_DEBUG(3), "dns_request_createraw");
 702
 703         if (isblackholed(requestmgr->dispatchmgr, destaddr))
 704                 return (DNS_R_BLACKHOLED);
 705
 706         request = NULL;
 707         result = new_request(mctx, &request);
 708         if (result != ISC_R_SUCCESS)
 709                 return (result);
 710
 711         if (udptimeout == 0 && udpretries != 0) {
 712                 udptimeout = timeout / (udpretries + 1);
 713                 if (udptimeout == 0)
 714                         udptimeout = 1;
 715         }
 716         request->udpcount = udpretries;
 717
 718         /*
 719          * Create timer now.  We will set it below once.
 720          */
 721         result = isc_timer_create(requestmgr->timermgr, isc_timertype_inactive,
 722                                   NULL, NULL, task, req_timeout, request,
 723                                   &request->timer);
 724         if (result != ISC_R_SUCCESS)
 725                 goto cleanup;
 726
 727         request->event = (dns_requestevent_t *)
 728                 isc_event_allocate(mctx, task, DNS_EVENT_REQUESTDONE,
 729                                    action, arg, sizeof(dns_requestevent_t));
 730         if (request->event == NULL) {
 731                 result = ISC_R_NOMEMORY;
 732                 goto cleanup;
 733         }
 734         isc_task_attach(task, &tclone);
 735         request->event->ev_sender = task;
 736         request->event->request = request;
 737         request->event->result = ISC_R_FAILURE;
 738
 739         isc_buffer_usedregion(msgbuf, &r);
 740         if (r.length < DNS_MESSAGE_HEADERLEN || r.length > 65535) {
 741                 result = DNS_R_FORMERR;
 742                 goto cleanup;
 743         }
 744
 745         if ((options & DNS_REQUESTOPT_TCP) != 0 || r.length > 512)
 746                 tcp = ISC_TRUE;
 747
 748         result = get_dispatch(tcp, requestmgr, srcaddr, destaddr,
 749                               &request->dispatch);
 750         if (result != ISC_R_SUCCESS)
 751                 goto cleanup;
 752
 753         result = dns_dispatch_addresponse2(request->dispatch, destaddr, task,
 754                                            req_response, request, &id,
 755                                            &request->dispentry,
 756                                            requestmgr->socketmgr);
 757         if (result != ISC_R_SUCCESS)
 758                 goto cleanup;
 759
 760         socket = req_getsocket(request);
 761         INSIST(socket != NULL);
 762
 763         result = isc_buffer_allocate(mctx, &request->query,
 764                                      r.length + (tcp ? 2 : 0));
 765         if (result != ISC_R_SUCCESS)
 766                 goto cleanup;
 767         if (tcp)
 768                 isc_buffer_putuint16(request->query, (isc_uint16_t)r.length);
 769         result = isc_buffer_copyregion(request->query, &r);
 770         if (result != ISC_R_SUCCESS)
 771                 goto cleanup;
 772
 773         /* Add message ID. */
 774         isc_buffer_usedregion(request->query, &r);
 775         if (tcp)
 776                 isc_region_consume(&r, 2);
 777         r.base[0] = (id>>8) & 0xff;
 778         r.base[1] = id & 0xff;
 779
 780         LOCK(&requestmgr->lock);
 781         if (requestmgr->exiting) {
 782                 UNLOCK(&requestmgr->lock);
 783                 result = ISC_R_SHUTTINGDOWN;
 784                 goto cleanup;
 785         }
 786         requestmgr_attach(requestmgr, &request->requestmgr);
 787         request->hash = mgr_gethash(requestmgr);
 788         ISC_LIST_APPEND(requestmgr->requests, request, link);
 789         UNLOCK(&requestmgr->lock);
 790
 791         result = set_timer(request->timer, timeout, tcp ? 0 : udptimeout);
 792         if (result != ISC_R_SUCCESS)
 793                 goto unlink;
 794
 795         request->destaddr = *destaddr;
 796         if (tcp) {
 797                 result = isc_socket_connect(socket, destaddr, task,
 798                                             req_connected, request);
 799                 if (result != ISC_R_SUCCESS)
 800                         goto unlink;
 801                 request->flags |= DNS_REQUEST_F_CONNECTING|DNS_REQUEST_F_TCP;
 802         } else {
 803                 result = req_send(request, task, destaddr);
 804                 if (result != ISC_R_SUCCESS)
 805                         goto unlink;
 806         }
 807
 808         req_log(ISC_LOG_DEBUG(3), "dns_request_createraw: request %p",
 809                 request);
 810         *requestp = request;
 811         return (ISC_R_SUCCESS);
 812
 813  unlink:
 814         LOCK(&requestmgr->lock);
 815         ISC_LIST_UNLINK(requestmgr->requests, request, link);
 816         UNLOCK(&requestmgr->lock);
 817
 818  cleanup:
 819         if (tclone != NULL)
 820                 isc_task_detach(&tclone);
 821         req_destroy(request);
 822         req_log(ISC_LOG_DEBUG(3), "dns_request_createraw: failed %s",
 823                 dns_result_totext(result));
 824         return (result);
 825 }
 826
 827 isc_result_t
 828 dns_request_create(dns_requestmgr_t *requestmgr, dns_message_t *message,
 829                    isc_sockaddr_t *address, unsigned int options,
 830                    dns_tsigkey_t *key,
 831                    unsigned int timeout, isc_task_t *task,
 832                    isc_taskaction_t action, void *arg,
 833                    dns_request_t **requestp)
 834 {
 835         return (dns_request_createvia3(requestmgr, message, NULL, address,
 836                                        options, key, timeout, 0, 0, task,
 837                                        action, arg, requestp));
 838 }
 839
 840 isc_result_t
 841 dns_request_createvia(dns_requestmgr_t *requestmgr, dns_message_t *message,
 842                       isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 843                       unsigned int options, dns_tsigkey_t *key,
 844                       unsigned int timeout, isc_task_t *task,
 845                       isc_taskaction_t action, void *arg,
 846                       dns_request_t **requestp)
 847 {
 848         return(dns_request_createvia3(requestmgr, message, srcaddr, destaddr,
 849                                       options, key, timeout, 0, 0, task,
 850                                       action, arg, requestp));
 851 }
 852
 853 isc_result_t
 854 dns_request_createvia2(dns_requestmgr_t *requestmgr, dns_message_t *message,
 855                        isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 856                        unsigned int options, dns_tsigkey_t *key,
 857                        unsigned int timeout, unsigned int udptimeout,
 858                        isc_task_t *task, isc_taskaction_t action, void *arg,
 859                        dns_request_t **requestp)
 860 {
 861         unsigned int udpretries = 0;
 862
 863         if (udptimeout != 0)
 864                 udpretries = timeout / udptimeout;
 865         return (dns_request_createvia3(requestmgr, message, srcaddr, destaddr,
 866                                        options, key, timeout, udptimeout,
 867                                        udpretries, task, action, arg,
 868                                        requestp));
 869 }
 870
 871 isc_result_t
 872 dns_request_createvia3(dns_requestmgr_t *requestmgr, dns_message_t *message,
 873                        isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 874                        unsigned int options, dns_tsigkey_t *key,
 875                        unsigned int timeout, unsigned int udptimeout,
 876                        unsigned int udpretries, isc_task_t *task,
 877                        isc_taskaction_t action, void *arg,
 878                        dns_request_t **requestp)
 879 {
 880         dns_request_t *request = NULL;
 881         isc_task_t *tclone = NULL;
 882         isc_socket_t *socket = NULL;
 883         isc_result_t result;
 884         isc_mem_t *mctx;
 885         dns_messageid_t id;
 886         isc_boolean_t tcp;
 887         isc_boolean_t setkey = ISC_TRUE;
 888
 889         REQUIRE(VALID_REQUESTMGR(requestmgr));
 890         REQUIRE(message != NULL);
 891         REQUIRE(destaddr != NULL);
 892         REQUIRE(task != NULL);
 893         REQUIRE(action != NULL);
 894         REQUIRE(requestp != NULL && *requestp == NULL);
 895         REQUIRE(timeout > 0);
 896         if (srcaddr != NULL)
 897                 REQUIRE(isc_sockaddr_pf(srcaddr) == isc_sockaddr_pf(destaddr));
 898
 899         mctx = requestmgr->mctx;
 900
 901         req_log(ISC_LOG_DEBUG(3), "dns_request_createvia");
 902
 903         if (isblackholed(requestmgr->dispatchmgr, destaddr))
 904                 return (DNS_R_BLACKHOLED);
 905
 906         request = NULL;
 907         result = new_request(mctx, &request);
 908         if (result != ISC_R_SUCCESS)
 909                 return (result);
 910
 911         if (udptimeout == 0 && udpretries != 0) {
 912                 udptimeout = timeout / (udpretries + 1);
 913                 if (udptimeout == 0)
 914                         udptimeout = 1;
 915         }
 916         request->udpcount = udpretries;
 917
 918         /*
 919          * Create timer now.  We will set it below once.
 920          */
 921         result = isc_timer_create(requestmgr->timermgr, isc_timertype_inactive,
 922                                   NULL, NULL, task, req_timeout, request,
 923                                   &request->timer);
 924         if (result != ISC_R_SUCCESS)
 925                 goto cleanup;
 926
 927         request->event = (dns_requestevent_t *)
 928                 isc_event_allocate(mctx, task, DNS_EVENT_REQUESTDONE,
 929                                    action, arg, sizeof(dns_requestevent_t));
 930         if (request->event == NULL) {
 931                 result = ISC_R_NOMEMORY;
 932                 goto cleanup;
 933         }
 934         isc_task_attach(task, &tclone);
 935         request->event->ev_sender = task;
 936         request->event->request = request;
 937         request->event->result = ISC_R_FAILURE;
 938         if (key != NULL)
 939                 dns_tsigkey_attach(key, &request->tsigkey);
 940
 941  use_tcp:
 942         tcp = ISC_TF((options & DNS_REQUESTOPT_TCP) != 0);
 943         result = get_dispatch(tcp, requestmgr, srcaddr, destaddr,
 944                               &request->dispatch);
 945         if (result != ISC_R_SUCCESS)
 946                 goto cleanup;
 947
 948         result = dns_dispatch_addresponse2(request->dispatch, destaddr, task,
 949                                            req_response, request, &id,
 950                                            &request->dispentry,
 951                                            requestmgr->socketmgr);
 952         if (result != ISC_R_SUCCESS)
 953                 goto cleanup;
 954         socket = req_getsocket(request);
 955         INSIST(socket != NULL);
 956
 957         message->id = id;
 958         if (setkey) {
 959                 result = dns_message_settsigkey(message, request->tsigkey);
 960                 if (result != ISC_R_SUCCESS)
 961                         goto cleanup;
 962         }
 963         result = req_render(message, &request->query, options, mctx);
 964         if (result == DNS_R_USETCP &&
 965             (options & DNS_REQUESTOPT_TCP) == 0) {
 966                 /*
 967                  * Try again using TCP.
 968                  */
 969                 dns_message_renderreset(message);
 970                 dns_dispatch_removeresponse(&request->dispentry, NULL);
 971                 dns_dispatch_detach(&request->dispatch);
 972                 socket = NULL;
 973                 options |= DNS_REQUESTOPT_TCP;
 974                 setkey = ISC_FALSE;
 975                 goto use_tcp;
 976         }
 977         if (result != ISC_R_SUCCESS)
 978                 goto cleanup;
 979
 980         result = dns_message_getquerytsig(message, mctx, &request->tsig);
 981         if (result != ISC_R_SUCCESS)
 982                 goto cleanup;
 983
 984         LOCK(&requestmgr->lock);
 985         if (requestmgr->exiting) {
 986                 UNLOCK(&requestmgr->lock);
 987                 result = ISC_R_SHUTTINGDOWN;
 988                 goto cleanup;
 989         }
 990         requestmgr_attach(requestmgr, &request->requestmgr);
 991         request->hash = mgr_gethash(requestmgr);
 992         ISC_LIST_APPEND(requestmgr->requests, request, link);
 993         UNLOCK(&requestmgr->lock);
 994
 995         result = set_timer(request->timer, timeout, tcp ? 0 : udptimeout);
 996         if (result != ISC_R_SUCCESS)
 997                 goto unlink;
 998
 999         request->destaddr = *destaddr;
1000         if (tcp) {
1001                 result = isc_socket_connect(socket, destaddr, task,
1002                                             req_connected, request);
1003                 if (result != ISC_R_SUCCESS)
1004                         goto unlink;
1005                 request->flags |= DNS_REQUEST_F_CONNECTING|DNS_REQUEST_F_TCP;
1006         } else {
1007                 result = req_send(request, task, destaddr);
1008                 if (result != ISC_R_SUCCESS)
1009                         goto unlink;
1010         }
1011
1012         req_log(ISC_LOG_DEBUG(3), "dns_request_createvia: request %p",
1013                 request);
1014         *requestp = request;
1015         return (ISC_R_SUCCESS);
1016
1017  unlink:
1018         LOCK(&requestmgr->lock);
1019         ISC_LIST_UNLINK(requestmgr->requests, request, link);
1020         UNLOCK(&requestmgr->lock);
1021
1022  cleanup:
1023         if (tclone != NULL)
1024                 isc_task_detach(&tclone);
1025         req_destroy(request);
1026         req_log(ISC_LOG_DEBUG(3), "dns_request_createvia: failed %s",
1027                 dns_result_totext(result));
1028         return (result);
1029 }
1030
1031 static isc_result_t
1032 req_render(dns_message_t *message, isc_buffer_t **bufferp,
1033            unsigned int options, isc_mem_t *mctx)
1034 {
1035         isc_buffer_t *buf1 = NULL;
1036         isc_buffer_t *buf2 = NULL;
1037         isc_result_t result;
1038         isc_region_t r;
1039         isc_boolean_t tcp = ISC_FALSE;
1040         dns_compress_t cctx;
1041         isc_boolean_t cleanup_cctx = ISC_FALSE;
1042
1043         REQUIRE(bufferp != NULL && *bufferp == NULL);
1044
1045         req_log(ISC_LOG_DEBUG(3), "request_render");
1046
1047         /*
1048          * Create buffer able to hold largest possible message.
1049          */
1050         result = isc_buffer_allocate(mctx, &buf1, 65535);
1051         if (result != ISC_R_SUCCESS)
1052                 return (result);
1053
1054         result = dns_compress_init(&cctx, -1, mctx);
1055         if (result != ISC_R_SUCCESS)
1056                 return (result);
1057         cleanup_cctx = ISC_TRUE;
1058
1059         /*
1060          * Render message.
1061          */
1062         result = dns_message_renderbegin(message, &cctx, buf1);
1063         if (result != ISC_R_SUCCESS)
1064                 goto cleanup;
1065         result = dns_message_rendersection(message, DNS_SECTION_QUESTION, 0);
1066         if (result != ISC_R_SUCCESS)
1067                 goto cleanup;
1068         result = dns_message_rendersection(message, DNS_SECTION_ANSWER, 0);
1069         if (result != ISC_R_SUCCESS)
1070                 goto cleanup;
1071         result = dns_message_rendersection(message, DNS_SECTION_AUTHORITY, 0);
1072         if (result != ISC_R_SUCCESS)
1073                 goto cleanup;
1074         result = dns_message_rendersection(message, DNS_SECTION_ADDITIONAL, 0);
1075         if (result != ISC_R_SUCCESS)
1076                 goto cleanup;
1077         result = dns_message_renderend(message);
1078         if (result != ISC_R_SUCCESS)
1079                 goto cleanup;
1080
1081         dns_compress_invalidate(&cctx);
1082         cleanup_cctx = ISC_FALSE;
1083
1084         /*
1085          * Copy rendered message to exact sized buffer.
1086          */
1087         isc_buffer_usedregion(buf1, &r);
1088         if ((options & DNS_REQUESTOPT_TCP) != 0) {
1089                 tcp = ISC_TRUE;
1090         } else if (r.length > 512) {
1091                 result = DNS_R_USETCP;
1092                 goto cleanup;
1093         }
1094         result = isc_buffer_allocate(mctx, &buf2, r.length + (tcp ? 2 : 0));
1095         if (result != ISC_R_SUCCESS)
1096                 goto cleanup;
1097         if (tcp)
1098                 isc_buffer_putuint16(buf2, (isc_uint16_t)r.length);
1099         result = isc_buffer_copyregion(buf2, &r);
1100         if (result != ISC_R_SUCCESS)
1101                 goto cleanup;
1102
1103         /*
1104          * Cleanup and return.
1105          */
1106         isc_buffer_free(&buf1);
1107         *bufferp = buf2;
1108         return (ISC_R_SUCCESS);
1109
1110  cleanup:
1111         dns_message_renderreset(message);
1112         if (buf1 != NULL)
1113                 isc_buffer_free(&buf1);
1114         if (buf2 != NULL)
1115                 isc_buffer_free(&buf2);
1116         if (cleanup_cctx)
1117                 dns_compress_invalidate(&cctx);
1118         return (result);
1119 }
1120
1121
1122 /*
1123  * If this request is no longer waiting for events,
1124  * send the completion event.  This will ultimately
1125  * cause the request to be destroyed.
1126  *
1127  * Requires:
1128  *      'request' is locked by the caller.
1129  */
1130 static void
1131 send_if_done(dns_request_t *request, isc_result_t result) {
1132         if (!DNS_REQUEST_CONNECTING(request) &&
1133             !DNS_REQUEST_SENDING(request) &&
1134             !request->canceling)
1135                 req_sendevent(request, result);
1136 }
1137
1138 /*
1139  * Handle the control event.
1140  */
1141 static void
1142 do_cancel(isc_task_t *task, isc_event_t *event) {
1143         dns_request_t *request = event->ev_arg;
1144         UNUSED(task);
1145         INSIST(event->ev_type == DNS_EVENT_REQUESTCONTROL);
1146         LOCK(&request->requestmgr->locks[request->hash]);
1147         request->canceling = ISC_FALSE;
1148         if (!DNS_REQUEST_CANCELED(request))
1149                 req_cancel(request);
1150         send_if_done(request, ISC_R_CANCELED);
1151         UNLOCK(&request->requestmgr->locks[request->hash]);
1152 }
1153
1154 void
1155 dns_request_cancel(dns_request_t *request) {
1156         REQUIRE(VALID_REQUEST(request));
1157
1158         req_log(ISC_LOG_DEBUG(3), "dns_request_cancel: request %p", request);
1159
1160         REQUIRE(VALID_REQUEST(request));
1161
1162         LOCK(&request->requestmgr->locks[request->hash]);
1163         if (!request->canceling && !DNS_REQUEST_CANCELED(request)) {
1164                 isc_event_t *ev =  &request->ctlevent;
1165                 isc_task_send(request->event->ev_sender, &ev);
1166                 request->canceling = ISC_TRUE;
1167         }
1168         UNLOCK(&request->requestmgr->locks[request->hash]);
1169 }
1170
1171 isc_result_t
1172 dns_request_getresponse(dns_request_t *request, dns_message_t *message,
1173                         unsigned int options)
1174 {
1175         isc_result_t result;
1176
1177         REQUIRE(VALID_REQUEST(request));
1178         REQUIRE(request->answer != NULL);
1179
1180         req_log(ISC_LOG_DEBUG(3), "dns_request_getresponse: request %p",
1181                 request);
1182
1183         result = dns_message_setquerytsig(message, request->tsig);
1184         if (result != ISC_R_SUCCESS)
1185                 return (result);
1186         result = dns_message_settsigkey(message, request->tsigkey);
1187         if (result != ISC_R_SUCCESS)
1188                 return (result);
1189         result = dns_message_parse(message, request->answer, options);
1190         if (result != ISC_R_SUCCESS)
1191                 return (result);
1192         if (request->tsigkey != NULL)
1193                 result = dns_tsig_verify(request->answer, message, NULL, NULL);
1194         return (result);
1195 }
1196
1197 isc_boolean_t
1198 dns_request_usedtcp(dns_request_t *request) {
1199         REQUIRE(VALID_REQUEST(request));
1200
1201         return (ISC_TF((request->flags & DNS_REQUEST_F_TCP) != 0));
1202 }
1203
1204 void
1205 dns_request_destroy(dns_request_t **requestp) {
1206         dns_request_t *request;
1207
1208         REQUIRE(requestp != NULL && VALID_REQUEST(*requestp));
1209
1210         request = *requestp;
1211
1212         req_log(ISC_LOG_DEBUG(3), "dns_request_destroy: request %p", request);
1213
1214         LOCK(&request->requestmgr->lock);
1215         LOCK(&request->requestmgr->locks[request->hash]);
1216         ISC_LIST_UNLINK(request->requestmgr->requests, request, link);
1217         INSIST(!DNS_REQUEST_CONNECTING(request));
1218         INSIST(!DNS_REQUEST_SENDING(request));
1219         UNLOCK(&request->requestmgr->locks[request->hash]);
1220         UNLOCK(&request->requestmgr->lock);
1221
1222         /*
1223          * These should have been cleaned up by req_cancel() before
1224          * the completion event was sent.
1225          */
1226         INSIST(!ISC_LINK_LINKED(request, link));
1227         INSIST(request->dispentry == NULL);
1228         INSIST(request->dispatch == NULL);
1229         INSIST(request->timer == NULL);
1230
1231         req_destroy(request);
1232
1233         *requestp = NULL;
1234 }
1235
1236 /***
1237  *** Private: request.
1238  ***/
1239
1240 static isc_socket_t *
1241 req_getsocket(dns_request_t *request) {
1242         unsigned int dispattr;
1243         isc_socket_t *socket;
1244
1245         dispattr = dns_dispatch_getattributes(request->dispatch);
1246         if ((dispattr & DNS_DISPATCHATTR_EXCLUSIVE) != 0) {
1247                 INSIST(request->dispentry != NULL);
1248                 socket = dns_dispatch_getentrysocket(request->dispentry);
1249         } else
1250                 socket = dns_dispatch_getsocket(request->dispatch);
1251
1252         return (socket);
1253 }
1254
1255 static void
1256 req_connected(isc_task_t *task, isc_event_t *event) {
1257         isc_socketevent_t *sevent = (isc_socketevent_t *)event;
1258         isc_result_t result;
1259         dns_request_t *request = event->ev_arg;
1260
1261         REQUIRE(event->ev_type == ISC_SOCKEVENT_CONNECT);
1262         REQUIRE(VALID_REQUEST(request));
1263         REQUIRE(DNS_REQUEST_CONNECTING(request));
1264
1265         req_log(ISC_LOG_DEBUG(3), "req_connected: request %p", request);
1266
1267         LOCK(&request->requestmgr->locks[request->hash]);
1268         request->flags &= ~DNS_REQUEST_F_CONNECTING;
1269
1270         if (DNS_REQUEST_CANCELED(request)) {
1271                 /*
1272                  * Send delayed event.
1273                  */
1274                 if (DNS_REQUEST_TIMEDOUT(request))
1275                         send_if_done(request, ISC_R_TIMEDOUT);
1276                 else
1277                         send_if_done(request, ISC_R_CANCELED);
1278         } else {
1279                 dns_dispatch_starttcp(request->dispatch);
1280                 result = sevent->result;
1281                 if (result == ISC_R_SUCCESS)
1282                         result = req_send(request, task, NULL);
1283
1284                 if (result != ISC_R_SUCCESS) {
1285                         req_cancel(request);
1286                         send_if_done(request, ISC_R_CANCELED);
1287                 }
1288         }
1289         UNLOCK(&request->requestmgr->locks[request->hash]);
1290         isc_event_free(&event);
1291 }
1292
1293 static void
1294 req_senddone(isc_task_t *task, isc_event_t *event) {
1295         isc_socketevent_t *sevent = (isc_socketevent_t *)event;
1296         dns_request_t *request = event->ev_arg;
1297
1298         REQUIRE(event->ev_type == ISC_SOCKEVENT_SENDDONE);
1299         REQUIRE(VALID_REQUEST(request));
1300         REQUIRE(DNS_REQUEST_SENDING(request));
1301
1302         req_log(ISC_LOG_DEBUG(3), "req_senddone: request %p", request);
1303
1304         UNUSED(task);
1305
1306         LOCK(&request->requestmgr->locks[request->hash]);
1307         request->flags &= ~DNS_REQUEST_F_SENDING;
1308
1309         if (DNS_REQUEST_CANCELED(request)) {
1310                 /*
1311                  * Send delayed event.
1312                  */
1313                 if (DNS_REQUEST_TIMEDOUT(request))
1314                         send_if_done(request, ISC_R_TIMEDOUT);
1315                 else
1316                         send_if_done(request, ISC_R_CANCELED);
1317         } else if (sevent->result != ISC_R_SUCCESS) {
1318                         req_cancel(request);
1319                         send_if_done(request, ISC_R_CANCELED);
1320         }
1321         UNLOCK(&request->requestmgr->locks[request->hash]);
1322
1323         isc_event_free(&event);
1324 }
1325
1326 static void
1327 req_response(isc_task_t *task, isc_event_t *event) {
1328         isc_result_t result;
1329         dns_request_t *request = event->ev_arg;
1330         dns_dispatchevent_t *devent = (dns_dispatchevent_t *)event;
1331         isc_region_t r;
1332
1333         REQUIRE(VALID_REQUEST(request));
1334         REQUIRE(event->ev_type == DNS_EVENT_DISPATCH);
1335
1336         UNUSED(task);
1337
1338         req_log(ISC_LOG_DEBUG(3), "req_response: request %p: %s", request,
1339                 dns_result_totext(devent->result));
1340
1341         LOCK(&request->requestmgr->locks[request->hash]);
1342         result = devent->result;
1343         if (result != ISC_R_SUCCESS)
1344                 goto done;
1345
1346         /*
1347          * Copy buffer to request.
1348          */
1349         isc_buffer_usedregion(&devent->buffer, &r);
1350         result = isc_buffer_allocate(request->mctx, &request->answer,
1351                                      r.length);
1352         if (result != ISC_R_SUCCESS)
1353                 goto done;
1354         result = isc_buffer_copyregion(request->answer, &r);
1355         if (result != ISC_R_SUCCESS)
1356                 isc_buffer_free(&request->answer);
1357  done:
1358         /*
1359          * Cleanup.
1360          */
1361         dns_dispatch_removeresponse(&request->dispentry, &devent);
1362         req_cancel(request);
1363         /*
1364          * Send completion event.
1365          */
1366         send_if_done(request, result);
1367         UNLOCK(&request->requestmgr->locks[request->hash]);
1368 }
1369
1370 static void
1371 req_timeout(isc_task_t *task, isc_event_t *event) {
1372         dns_request_t *request = event->ev_arg;
1373         isc_result_t result;
1374
1375         REQUIRE(VALID_REQUEST(request));
1376
1377         req_log(ISC_LOG_DEBUG(3), "req_timeout: request %p", request);
1378
1379         UNUSED(task);
1380         LOCK(&request->requestmgr->locks[request->hash]);
1381         if (event->ev_type == ISC_TIMEREVENT_TICK &&
1382             request->udpcount-- != 0) {
1383                 if (! DNS_REQUEST_SENDING(request)) {
1384                         result = req_send(request, task, &request->destaddr);
1385                         if (result != ISC_R_SUCCESS) {
1386                                 req_cancel(request);
1387                                 send_if_done(request, result);
1388                         }
1389                 }
1390         } else {
1391                 request->flags |= DNS_REQUEST_F_TIMEDOUT;
1392                 req_cancel(request);
1393                 send_if_done(request, ISC_R_TIMEDOUT);
1394         }
1395         UNLOCK(&request->requestmgr->locks[request->hash]);
1396         isc_event_free(&event);
1397 }
1398
1399 static void
1400 req_sendevent(dns_request_t *request, isc_result_t result) {
1401         isc_task_t *task;
1402
1403         REQUIRE(VALID_REQUEST(request));
1404
1405         req_log(ISC_LOG_DEBUG(3), "req_sendevent: request %p", request);
1406
1407         /*
1408          * Lock held by caller.
1409          */
1410         task = request->event->ev_sender;
1411         request->event->ev_sender = request;
1412         request->event->result = result;
1413         isc_task_sendanddetach(&task, (isc_event_t **)&request->event);
1414 }
1415
1416 static void
1417 req_destroy(dns_request_t *request) {
1418         isc_mem_t *mctx;
1419
1420         REQUIRE(VALID_REQUEST(request));
1421
1422         req_log(ISC_LOG_DEBUG(3), "req_destroy: request %p", request);
1423
1424         request->magic = 0;
1425         if (request->query != NULL)
1426                 isc_buffer_free(&request->query);
1427         if (request->answer != NULL)
1428                 isc_buffer_free(&request->answer);
1429         if (request->event != NULL)
1430                 isc_event_free((isc_event_t **)&request->event);
1431         if (request->dispentry != NULL)
1432                 dns_dispatch_removeresponse(&request->dispentry, NULL);
1433         if (request->dispatch != NULL)
1434                 dns_dispatch_detach(&request->dispatch);
1435         if (request->timer != NULL)
1436                 isc_timer_detach(&request->timer);
1437         if (request->tsig != NULL)
1438                 isc_buffer_free(&request->tsig);
1439         if (request->tsigkey != NULL)
1440                 dns_tsigkey_detach(&request->tsigkey);
1441         if (request->requestmgr != NULL)
1442                 requestmgr_detach(&request->requestmgr);
1443         mctx = request->mctx;
1444         isc_mem_put(mctx, request, sizeof(*request));
1445         isc_mem_detach(&mctx);
1446 }
1447
1448 /*
1449  * Stop the current request.  Must be called from the request's task.
1450  */
1451 static void
1452 req_cancel(dns_request_t *request) {
1453         isc_socket_t *socket;
1454         unsigned int dispattr;
1455
1456         REQUIRE(VALID_REQUEST(request));
1457
1458         req_log(ISC_LOG_DEBUG(3), "req_cancel: request %p", request);
1459
1460         /*
1461          * Lock held by caller.
1462          */
1463         request->flags |= DNS_REQUEST_F_CANCELED;
1464
1465         if (request->timer != NULL)
1466                 isc_timer_detach(&request->timer);
1467         dispattr = dns_dispatch_getattributes(request->dispatch);
1468         socket = NULL;
1469         if (DNS_REQUEST_CONNECTING(request) || DNS_REQUEST_SENDING(request)) {
1470                 if ((dispattr & DNS_DISPATCHATTR_EXCLUSIVE) != 0) {
1471                         if (request->dispentry != NULL) {
1472                                 socket = dns_dispatch_getentrysocket(
1473                                         request->dispentry);
1474                         }
1475                 } else
1476                         socket = dns_dispatch_getsocket(request->dispatch);
1477                 if (DNS_REQUEST_CONNECTING(request) && socket != NULL)
1478                         isc_socket_cancel(socket, NULL, ISC_SOCKCANCEL_CONNECT);
1479                 if (DNS_REQUEST_SENDING(request) && socket != NULL)
1480                         isc_socket_cancel(socket, NULL, ISC_SOCKCANCEL_SEND);
1481         }
1482         if (request->dispentry != NULL)
1483                 dns_dispatch_removeresponse(&request->dispentry, NULL);
1484         dns_dispatch_detach(&request->dispatch);
1485 }
1486
1487 static void
1488 req_log(int level, const char *fmt, ...) {
1489         va_list ap;
1490
1491         va_start(ap, fmt);
1492         isc_log_vwrite(dns_lctx, DNS_LOGCATEGORY_GENERAL,
1493                        DNS_LOGMODULE_REQUEST, level, fmt, ap);
1494         va_end(ap);
1495 }