contrib/bind9/lib/dns/request.c

   1 /*
   2  * Copyright (C) 2004-2012  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 /* $Id$ */
  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 {
 452         dns_request_t *request;
 453
 454         request = isc_mem_get(mctx, sizeof(*request));
 455         if (request == NULL)
 456                 return (ISC_R_NOMEMORY);
 457
 458         /*
 459          * Zero structure.
 460          */
 461         request->magic = 0;
 462         request->mctx = NULL;
 463         request->flags = 0;
 464         ISC_LINK_INIT(request, link);
 465         request->query = NULL;
 466         request->answer = NULL;
 467         request->event = NULL;
 468         request->dispatch = NULL;
 469         request->dispentry = NULL;
 470         request->timer = NULL;
 471         request->requestmgr = NULL;
 472         request->tsig = NULL;
 473         request->tsigkey = NULL;
 474         ISC_EVENT_INIT(&request->ctlevent, sizeof(request->ctlevent), 0, NULL,
 475                        DNS_EVENT_REQUESTCONTROL, do_cancel, request, NULL,
 476                        NULL, NULL);
 477         request->canceling = ISC_FALSE;
 478         request->udpcount = 0;
 479
 480         isc_mem_attach(mctx, &request->mctx);
 481
 482         request->magic = REQUEST_MAGIC;
 483         *requestp = request;
 484         return (ISC_R_SUCCESS);
 485 }
 486
 487
 488 static isc_boolean_t
 489 isblackholed(dns_dispatchmgr_t *dispatchmgr, isc_sockaddr_t *destaddr) {
 490         dns_acl_t *blackhole;
 491         isc_netaddr_t netaddr;
 492         int match;
 493         isc_boolean_t drop = ISC_FALSE;
 494         char netaddrstr[ISC_NETADDR_FORMATSIZE];
 495
 496         blackhole = dns_dispatchmgr_getblackhole(dispatchmgr);
 497         if (blackhole != NULL) {
 498                 isc_netaddr_fromsockaddr(&netaddr, destaddr);
 499                 if (dns_acl_match(&netaddr, NULL, blackhole,
 500                                   NULL, &match, NULL) == ISC_R_SUCCESS &&
 501                     match > 0)
 502                         drop = ISC_TRUE;
 503         }
 504         if (drop) {
 505                 isc_netaddr_format(&netaddr, netaddrstr, sizeof(netaddrstr));
 506                 req_log(ISC_LOG_DEBUG(10), "blackholed address %s", netaddrstr);
 507         }
 508         return (drop);
 509 }
 510
 511 static isc_result_t
 512 create_tcp_dispatch(dns_requestmgr_t *requestmgr, isc_sockaddr_t *srcaddr,
 513                     isc_sockaddr_t *destaddr, dns_dispatch_t **dispatchp)
 514 {
 515         isc_result_t result;
 516         isc_socket_t *socket = NULL;
 517         isc_sockaddr_t src;
 518         unsigned int attrs;
 519         isc_sockaddr_t bind_any;
 520
 521         result = isc_socket_create(requestmgr->socketmgr,
 522                                    isc_sockaddr_pf(destaddr),
 523                                    isc_sockettype_tcp, &socket);
 524         if (result != ISC_R_SUCCESS)
 525                 return (result);
 526 #ifndef BROKEN_TCP_BIND_BEFORE_CONNECT
 527         if (srcaddr == NULL) {
 528                 isc_sockaddr_anyofpf(&bind_any,
 529                                      isc_sockaddr_pf(destaddr));
 530                 result = isc_socket_bind(socket, &bind_any, 0);
 531         } else {
 532                 src = *srcaddr;
 533                 isc_sockaddr_setport(&src, 0);
 534                 result = isc_socket_bind(socket, &src, 0);
 535         }
 536         if (result != ISC_R_SUCCESS)
 537                 goto cleanup;
 538 #endif
 539         attrs = 0;
 540         attrs |= DNS_DISPATCHATTR_TCP;
 541         attrs |= DNS_DISPATCHATTR_PRIVATE;
 542         if (isc_sockaddr_pf(destaddr) == AF_INET)
 543                 attrs |= DNS_DISPATCHATTR_IPV4;
 544         else
 545                 attrs |= DNS_DISPATCHATTR_IPV6;
 546         attrs |= DNS_DISPATCHATTR_MAKEQUERY;
 547         result = dns_dispatch_createtcp(requestmgr->dispatchmgr,
 548                                         socket, requestmgr->taskmgr,
 549                                         4096, 2, 1, 1, 3, attrs,
 550                                         dispatchp);
 551 cleanup:
 552         isc_socket_detach(&socket);
 553         return (result);
 554 }
 555
 556 static isc_result_t
 557 find_udp_dispatch(dns_requestmgr_t *requestmgr, isc_sockaddr_t *srcaddr,
 558                   isc_sockaddr_t *destaddr, dns_dispatch_t **dispatchp)
 559 {
 560         dns_dispatch_t *disp = NULL;
 561         unsigned int attrs, attrmask;
 562
 563         if (srcaddr == NULL) {
 564                 switch (isc_sockaddr_pf(destaddr)) {
 565                 case PF_INET:
 566                         disp = requestmgr->dispatchv4;
 567                         break;
 568
 569                 case PF_INET6:
 570                         disp = requestmgr->dispatchv6;
 571                         break;
 572
 573                 default:
 574                         return (ISC_R_NOTIMPLEMENTED);
 575                 }
 576                 if (disp == NULL)
 577                         return (ISC_R_FAMILYNOSUPPORT);
 578                 dns_dispatch_attach(disp, dispatchp);
 579                 return (ISC_R_SUCCESS);
 580         }
 581         attrs = 0;
 582         attrs |= DNS_DISPATCHATTR_UDP;
 583         switch (isc_sockaddr_pf(srcaddr)) {
 584         case PF_INET:
 585                 attrs |= DNS_DISPATCHATTR_IPV4;
 586                 break;
 587
 588         case PF_INET6:
 589                 attrs |= DNS_DISPATCHATTR_IPV6;
 590                 break;
 591
 592         default:
 593                 return (ISC_R_NOTIMPLEMENTED);
 594         }
 595         attrmask = 0;
 596         attrmask |= DNS_DISPATCHATTR_UDP;
 597         attrmask |= DNS_DISPATCHATTR_TCP;
 598         attrmask |= DNS_DISPATCHATTR_IPV4;
 599         attrmask |= DNS_DISPATCHATTR_IPV6;
 600         return (dns_dispatch_getudp(requestmgr->dispatchmgr,
 601                                     requestmgr->socketmgr,
 602                                     requestmgr->taskmgr,
 603                                     srcaddr, 4096,
 604                                     1000, 32768, 16411, 16433,
 605                                     attrs, attrmask,
 606                                     dispatchp));
 607 }
 608
 609 static isc_result_t
 610 get_dispatch(isc_boolean_t tcp, dns_requestmgr_t *requestmgr,
 611              isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 612              dns_dispatch_t **dispatchp)
 613 {
 614         isc_result_t result;
 615         if (tcp)
 616                 result = create_tcp_dispatch(requestmgr, srcaddr,
 617                                              destaddr, dispatchp);
 618         else
 619                 result = find_udp_dispatch(requestmgr, srcaddr,
 620                                            destaddr, dispatchp);
 621         return (result);
 622 }
 623
 624 static isc_result_t
 625 set_timer(isc_timer_t *timer, unsigned int timeout, unsigned int udpresend) {
 626         isc_time_t expires;
 627         isc_interval_t interval;
 628         isc_result_t result;
 629         isc_timertype_t timertype;
 630
 631         isc_interval_set(&interval, timeout, 0);
 632         result = isc_time_nowplusinterval(&expires, &interval);
 633         isc_interval_set(&interval, udpresend, 0);
 634
 635         timertype = udpresend != 0 ? isc_timertype_limited : isc_timertype_once;
 636         if (result == ISC_R_SUCCESS)
 637                 result = isc_timer_reset(timer, timertype, &expires,
 638                                          &interval, ISC_FALSE);
 639         return (result);
 640 }
 641
 642 isc_result_t
 643 dns_request_createraw(dns_requestmgr_t *requestmgr, isc_buffer_t *msgbuf,
 644                       isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 645                       unsigned int options, unsigned int timeout,
 646                       isc_task_t *task, isc_taskaction_t action, void *arg,
 647                       dns_request_t **requestp)
 648 {
 649         return(dns_request_createraw3(requestmgr, msgbuf, srcaddr, destaddr,
 650                                       options, timeout, 0, 0, task, action,
 651                                       arg, requestp));
 652 }
 653
 654 isc_result_t
 655 dns_request_createraw2(dns_requestmgr_t *requestmgr, isc_buffer_t *msgbuf,
 656                        isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 657                        unsigned int options, unsigned int timeout,
 658                        unsigned int udptimeout, isc_task_t *task,
 659                        isc_taskaction_t action, void *arg,
 660                        dns_request_t **requestp)
 661 {
 662         unsigned int udpretries = 0;
 663
 664         if (udptimeout != 0)
 665                 udpretries = timeout / udptimeout;
 666
 667         return (dns_request_createraw3(requestmgr, msgbuf, srcaddr, destaddr,
 668                                        options, timeout, udptimeout,
 669                                        udpretries, task, action, arg,
 670                                        requestp));
 671 }
 672
 673 isc_result_t
 674 dns_request_createraw3(dns_requestmgr_t *requestmgr, isc_buffer_t *msgbuf,
 675                        isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 676                        unsigned int options, unsigned int timeout,
 677                        unsigned int udptimeout, unsigned int udpretries,
 678                        isc_task_t *task, isc_taskaction_t action, void *arg,
 679                        dns_request_t **requestp)
 680 {
 681         dns_request_t *request = NULL;
 682         isc_task_t *tclone = NULL;
 683         isc_socket_t *socket = NULL;
 684         isc_result_t result;
 685         isc_mem_t *mctx;
 686         dns_messageid_t id;
 687         isc_boolean_t tcp = ISC_FALSE;
 688         isc_region_t r;
 689
 690         REQUIRE(VALID_REQUESTMGR(requestmgr));
 691         REQUIRE(msgbuf != NULL);
 692         REQUIRE(destaddr != NULL);
 693         REQUIRE(task != NULL);
 694         REQUIRE(action != NULL);
 695         REQUIRE(requestp != NULL && *requestp == NULL);
 696         REQUIRE(timeout > 0);
 697         if (srcaddr != NULL)
 698                 REQUIRE(isc_sockaddr_pf(srcaddr) == isc_sockaddr_pf(destaddr));
 699
 700         mctx = requestmgr->mctx;
 701
 702         req_log(ISC_LOG_DEBUG(3), "dns_request_createraw");
 703
 704         if (isblackholed(requestmgr->dispatchmgr, destaddr))
 705                 return (DNS_R_BLACKHOLED);
 706
 707         request = NULL;
 708         result = new_request(mctx, &request);
 709         if (result != ISC_R_SUCCESS)
 710                 return (result);
 711
 712         if (udptimeout == 0 && udpretries != 0) {
 713                 udptimeout = timeout / (udpretries + 1);
 714                 if (udptimeout == 0)
 715                         udptimeout = 1;
 716         }
 717         request->udpcount = udpretries;
 718
 719         /*
 720          * Create timer now.  We will set it below once.
 721          */
 722         result = isc_timer_create(requestmgr->timermgr, isc_timertype_inactive,
 723                                   NULL, NULL, task, req_timeout, request,
 724                                   &request->timer);
 725         if (result != ISC_R_SUCCESS)
 726                 goto cleanup;
 727
 728         request->event = (dns_requestevent_t *)
 729                 isc_event_allocate(mctx, task, DNS_EVENT_REQUESTDONE,
 730                                    action, arg, sizeof(dns_requestevent_t));
 731         if (request->event == NULL) {
 732                 result = ISC_R_NOMEMORY;
 733                 goto cleanup;
 734         }
 735         isc_task_attach(task, &tclone);
 736         request->event->ev_sender = task;
 737         request->event->request = request;
 738         request->event->result = ISC_R_FAILURE;
 739
 740         isc_buffer_usedregion(msgbuf, &r);
 741         if (r.length < DNS_MESSAGE_HEADERLEN || r.length > 65535) {
 742                 result = DNS_R_FORMERR;
 743                 goto cleanup;
 744         }
 745
 746         if ((options & DNS_REQUESTOPT_TCP) != 0 || r.length > 512)
 747                 tcp = ISC_TRUE;
 748
 749         result = get_dispatch(tcp, requestmgr, srcaddr, destaddr,
 750                               &request->dispatch);
 751         if (result != ISC_R_SUCCESS)
 752                 goto cleanup;
 753
 754         result = dns_dispatch_addresponse2(request->dispatch, destaddr, task,
 755                                            req_response, request, &id,
 756                                            &request->dispentry,
 757                                            requestmgr->socketmgr);
 758         if (result != ISC_R_SUCCESS)
 759                 goto cleanup;
 760
 761         socket = req_getsocket(request);
 762         INSIST(socket != NULL);
 763
 764         result = isc_buffer_allocate(mctx, &request->query,
 765                                      r.length + (tcp ? 2 : 0));
 766         if (result != ISC_R_SUCCESS)
 767                 goto cleanup;
 768         if (tcp)
 769                 isc_buffer_putuint16(request->query, (isc_uint16_t)r.length);
 770         result = isc_buffer_copyregion(request->query, &r);
 771         if (result != ISC_R_SUCCESS)
 772                 goto cleanup;
 773
 774         /* Add message ID. */
 775         isc_buffer_usedregion(request->query, &r);
 776         if (tcp)
 777                 isc_region_consume(&r, 2);
 778         r.base[0] = (id>>8) & 0xff;
 779         r.base[1] = id & 0xff;
 780
 781         LOCK(&requestmgr->lock);
 782         if (requestmgr->exiting) {
 783                 UNLOCK(&requestmgr->lock);
 784                 result = ISC_R_SHUTTINGDOWN;
 785                 goto cleanup;
 786         }
 787         requestmgr_attach(requestmgr, &request->requestmgr);
 788         request->hash = mgr_gethash(requestmgr);
 789         ISC_LIST_APPEND(requestmgr->requests, request, link);
 790         UNLOCK(&requestmgr->lock);
 791
 792         result = set_timer(request->timer, timeout, tcp ? 0 : udptimeout);
 793         if (result != ISC_R_SUCCESS)
 794                 goto unlink;
 795
 796         request->destaddr = *destaddr;
 797         if (tcp) {
 798                 result = isc_socket_connect(socket, destaddr, task,
 799                                             req_connected, request);
 800                 if (result != ISC_R_SUCCESS)
 801                         goto unlink;
 802                 request->flags |= DNS_REQUEST_F_CONNECTING|DNS_REQUEST_F_TCP;
 803         } else {
 804                 result = req_send(request, task, destaddr);
 805                 if (result != ISC_R_SUCCESS)
 806                         goto unlink;
 807         }
 808
 809         req_log(ISC_LOG_DEBUG(3), "dns_request_createraw: request %p",
 810                 request);
 811         *requestp = request;
 812         return (ISC_R_SUCCESS);
 813
 814  unlink:
 815         LOCK(&requestmgr->lock);
 816         ISC_LIST_UNLINK(requestmgr->requests, request, link);
 817         UNLOCK(&requestmgr->lock);
 818
 819  cleanup:
 820         if (tclone != NULL)
 821                 isc_task_detach(&tclone);
 822         req_destroy(request);
 823         req_log(ISC_LOG_DEBUG(3), "dns_request_createraw: failed %s",
 824                 dns_result_totext(result));
 825         return (result);
 826 }
 827
 828 isc_result_t
 829 dns_request_create(dns_requestmgr_t *requestmgr, dns_message_t *message,
 830                    isc_sockaddr_t *address, unsigned int options,
 831                    dns_tsigkey_t *key,
 832                    unsigned int timeout, isc_task_t *task,
 833                    isc_taskaction_t action, void *arg,
 834                    dns_request_t **requestp)
 835 {
 836         return (dns_request_createvia3(requestmgr, message, NULL, address,
 837                                        options, key, timeout, 0, 0, task,
 838                                        action, arg, requestp));
 839 }
 840
 841 isc_result_t
 842 dns_request_createvia(dns_requestmgr_t *requestmgr, dns_message_t *message,
 843                       isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 844                       unsigned int options, dns_tsigkey_t *key,
 845                       unsigned int timeout, isc_task_t *task,
 846                       isc_taskaction_t action, void *arg,
 847                       dns_request_t **requestp)
 848 {
 849         return(dns_request_createvia3(requestmgr, message, srcaddr, destaddr,
 850                                       options, key, timeout, 0, 0, task,
 851                                       action, arg, requestp));
 852 }
 853
 854 isc_result_t
 855 dns_request_createvia2(dns_requestmgr_t *requestmgr, dns_message_t *message,
 856                        isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 857                        unsigned int options, dns_tsigkey_t *key,
 858                        unsigned int timeout, unsigned int udptimeout,
 859                        isc_task_t *task, isc_taskaction_t action, void *arg,
 860                        dns_request_t **requestp)
 861 {
 862         unsigned int udpretries = 0;
 863
 864         if (udptimeout != 0)
 865                 udpretries = timeout / udptimeout;
 866         return (dns_request_createvia3(requestmgr, message, srcaddr, destaddr,
 867                                        options, key, timeout, udptimeout,
 868                                        udpretries, task, action, arg,
 869                                        requestp));
 870 }
 871
 872 isc_result_t
 873 dns_request_createvia3(dns_requestmgr_t *requestmgr, dns_message_t *message,
 874                        isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 875                        unsigned int options, dns_tsigkey_t *key,
 876                        unsigned int timeout, unsigned int udptimeout,
 877                        unsigned int udpretries, isc_task_t *task,
 878                        isc_taskaction_t action, void *arg,
 879                        dns_request_t **requestp)
 880 {
 881         dns_request_t *request = NULL;
 882         isc_task_t *tclone = NULL;
 883         isc_socket_t *socket = NULL;
 884         isc_result_t result;
 885         isc_mem_t *mctx;
 886         dns_messageid_t id;
 887         isc_boolean_t tcp;
 888         isc_boolean_t setkey = ISC_TRUE;
 889
 890         REQUIRE(VALID_REQUESTMGR(requestmgr));
 891         REQUIRE(message != NULL);
 892         REQUIRE(destaddr != NULL);
 893         REQUIRE(task != NULL);
 894         REQUIRE(action != NULL);
 895         REQUIRE(requestp != NULL && *requestp == NULL);
 896         REQUIRE(timeout > 0);
 897         if (srcaddr != NULL)
 898                 REQUIRE(isc_sockaddr_pf(srcaddr) == isc_sockaddr_pf(destaddr));
 899
 900         mctx = requestmgr->mctx;
 901
 902         req_log(ISC_LOG_DEBUG(3), "dns_request_createvia");
 903
 904         if (isblackholed(requestmgr->dispatchmgr, destaddr))
 905                 return (DNS_R_BLACKHOLED);
 906
 907         request = NULL;
 908         result = new_request(mctx, &request);
 909         if (result != ISC_R_SUCCESS)
 910                 return (result);
 911
 912         if (udptimeout == 0 && udpretries != 0) {
 913                 udptimeout = timeout / (udpretries + 1);
 914                 if (udptimeout == 0)
 915                         udptimeout = 1;
 916         }
 917         request->udpcount = udpretries;
 918
 919         /*
 920          * Create timer now.  We will set it below once.
 921          */
 922         result = isc_timer_create(requestmgr->timermgr, isc_timertype_inactive,
 923                                   NULL, NULL, task, req_timeout, request,
 924                                   &request->timer);
 925         if (result != ISC_R_SUCCESS)
 926                 goto cleanup;
 927
 928         request->event = (dns_requestevent_t *)
 929                 isc_event_allocate(mctx, task, DNS_EVENT_REQUESTDONE,
 930                                    action, arg, sizeof(dns_requestevent_t));
 931         if (request->event == NULL) {
 932                 result = ISC_R_NOMEMORY;
 933                 goto cleanup;
 934         }
 935         isc_task_attach(task, &tclone);
 936         request->event->ev_sender = task;
 937         request->event->request = request;
 938         request->event->result = ISC_R_FAILURE;
 939         if (key != NULL)
 940                 dns_tsigkey_attach(key, &request->tsigkey);
 941
 942  use_tcp:
 943         tcp = ISC_TF((options & DNS_REQUESTOPT_TCP) != 0);
 944         result = get_dispatch(tcp, requestmgr, srcaddr, destaddr,
 945                               &request->dispatch);
 946         if (result != ISC_R_SUCCESS)
 947                 goto cleanup;
 948
 949         result = dns_dispatch_addresponse2(request->dispatch, destaddr, task,
 950                                            req_response, request, &id,
 951                                            &request->dispentry,
 952                                            requestmgr->socketmgr);
 953         if (result != ISC_R_SUCCESS)
 954                 goto cleanup;
 955         socket = req_getsocket(request);
 956         INSIST(socket != NULL);
 957
 958         message->id = id;
 959         if (setkey) {
 960                 result = dns_message_settsigkey(message, request->tsigkey);
 961                 if (result != ISC_R_SUCCESS)
 962                         goto cleanup;
 963         }
 964         result = req_render(message, &request->query, options, mctx);
 965         if (result == DNS_R_USETCP &&
 966             (options & DNS_REQUESTOPT_TCP) == 0) {
 967                 /*
 968                  * Try again using TCP.
 969                  */
 970                 dns_message_renderreset(message);
 971                 dns_dispatch_removeresponse(&request->dispentry, NULL);
 972                 dns_dispatch_detach(&request->dispatch);
 973                 socket = NULL;
 974                 options |= DNS_REQUESTOPT_TCP;
 975                 setkey = ISC_FALSE;
 976                 goto use_tcp;
 977         }
 978         if (result != ISC_R_SUCCESS)
 979                 goto cleanup;
 980
 981         result = dns_message_getquerytsig(message, mctx, &request->tsig);
 982         if (result != ISC_R_SUCCESS)
 983                 goto cleanup;
 984
 985         LOCK(&requestmgr->lock);
 986         if (requestmgr->exiting) {
 987                 UNLOCK(&requestmgr->lock);
 988                 result = ISC_R_SHUTTINGDOWN;
 989                 goto cleanup;
 990         }
 991         requestmgr_attach(requestmgr, &request->requestmgr);
 992         request->hash = mgr_gethash(requestmgr);
 993         ISC_LIST_APPEND(requestmgr->requests, request, link);
 994         UNLOCK(&requestmgr->lock);
 995
 996         result = set_timer(request->timer, timeout, tcp ? 0 : udptimeout);
 997         if (result != ISC_R_SUCCESS)
 998                 goto unlink;
 999
1000         request->destaddr = *destaddr;
1001         if (tcp) {
1002                 result = isc_socket_connect(socket, destaddr, task,
1003                                             req_connected, request);
1004                 if (result != ISC_R_SUCCESS)
1005                         goto unlink;
1006                 request->flags |= DNS_REQUEST_F_CONNECTING|DNS_REQUEST_F_TCP;
1007         } else {
1008                 result = req_send(request, task, destaddr);
1009                 if (result != ISC_R_SUCCESS)
1010                         goto unlink;
1011         }
1012
1013         req_log(ISC_LOG_DEBUG(3), "dns_request_createvia: request %p",
1014                 request);
1015         *requestp = request;
1016         return (ISC_R_SUCCESS);
1017
1018  unlink:
1019         LOCK(&requestmgr->lock);
1020         ISC_LIST_UNLINK(requestmgr->requests, request, link);
1021         UNLOCK(&requestmgr->lock);
1022
1023  cleanup:
1024         if (tclone != NULL)
1025                 isc_task_detach(&tclone);
1026         req_destroy(request);
1027         req_log(ISC_LOG_DEBUG(3), "dns_request_createvia: failed %s",
1028                 dns_result_totext(result));
1029         return (result);
1030 }
1031
1032 static isc_result_t
1033 req_render(dns_message_t *message, isc_buffer_t **bufferp,
1034            unsigned int options, isc_mem_t *mctx)
1035 {
1036         isc_buffer_t *buf1 = NULL;
1037         isc_buffer_t *buf2 = NULL;
1038         isc_result_t result;
1039         isc_region_t r;
1040         isc_boolean_t tcp = ISC_FALSE;
1041         dns_compress_t cctx;
1042         isc_boolean_t cleanup_cctx = ISC_FALSE;
1043
1044         REQUIRE(bufferp != NULL && *bufferp == NULL);
1045
1046         req_log(ISC_LOG_DEBUG(3), "request_render");
1047
1048         /*
1049          * Create buffer able to hold largest possible message.
1050          */
1051         result = isc_buffer_allocate(mctx, &buf1, 65535);
1052         if (result != ISC_R_SUCCESS)
1053                 return (result);
1054
1055         result = dns_compress_init(&cctx, -1, mctx);
1056         if (result != ISC_R_SUCCESS)
1057                 return (result);
1058         cleanup_cctx = ISC_TRUE;
1059
1060         if ((options & DNS_REQUESTOPT_CASE) != 0)
1061                 dns_compress_setsensitive(&cctx, ISC_TRUE);
1062
1063         /*
1064          * Render message.
1065          */
1066         result = dns_message_renderbegin(message, &cctx, buf1);
1067         if (result != ISC_R_SUCCESS)
1068                 goto cleanup;
1069         result = dns_message_rendersection(message, DNS_SECTION_QUESTION, 0);
1070         if (result != ISC_R_SUCCESS)
1071                 goto cleanup;
1072         result = dns_message_rendersection(message, DNS_SECTION_ANSWER, 0);
1073         if (result != ISC_R_SUCCESS)
1074                 goto cleanup;
1075         result = dns_message_rendersection(message, DNS_SECTION_AUTHORITY, 0);
1076         if (result != ISC_R_SUCCESS)
1077                 goto cleanup;
1078         result = dns_message_rendersection(message, DNS_SECTION_ADDITIONAL, 0);
1079         if (result != ISC_R_SUCCESS)
1080                 goto cleanup;
1081         result = dns_message_renderend(message);
1082         if (result != ISC_R_SUCCESS)
1083                 goto cleanup;
1084
1085         dns_compress_invalidate(&cctx);
1086         cleanup_cctx = ISC_FALSE;
1087
1088         /*
1089          * Copy rendered message to exact sized buffer.
1090          */
1091         isc_buffer_usedregion(buf1, &r);
1092         if ((options & DNS_REQUESTOPT_TCP) != 0) {
1093                 tcp = ISC_TRUE;
1094         } else if (r.length > 512) {
1095                 result = DNS_R_USETCP;
1096                 goto cleanup;
1097         }
1098         result = isc_buffer_allocate(mctx, &buf2, r.length + (tcp ? 2 : 0));
1099         if (result != ISC_R_SUCCESS)
1100                 goto cleanup;
1101         if (tcp)
1102                 isc_buffer_putuint16(buf2, (isc_uint16_t)r.length);
1103         result = isc_buffer_copyregion(buf2, &r);
1104         if (result != ISC_R_SUCCESS)
1105                 goto cleanup;
1106
1107         /*
1108          * Cleanup and return.
1109          */
1110         isc_buffer_free(&buf1);
1111         *bufferp = buf2;
1112         return (ISC_R_SUCCESS);
1113
1114  cleanup:
1115         dns_message_renderreset(message);
1116         if (buf1 != NULL)
1117                 isc_buffer_free(&buf1);
1118         if (buf2 != NULL)
1119                 isc_buffer_free(&buf2);
1120         if (cleanup_cctx)
1121                 dns_compress_invalidate(&cctx);
1122         return (result);
1123 }
1124
1125
1126 /*
1127  * If this request is no longer waiting for events,
1128  * send the completion event.  This will ultimately
1129  * cause the request to be destroyed.
1130  *
1131  * Requires:
1132  *      'request' is locked by the caller.
1133  */
1134 static void
1135 send_if_done(dns_request_t *request, isc_result_t result) {
1136         if (request->event != NULL && !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 }