lib/dns/request.c

   1 /*
   2  * Copyright (C) 2004-2009  Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (C) 2000-2002  Internet Software Consortium.
   4  *
   5  * Permission to use, copy, modify, and/or distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  15  * PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 /* $Id: request.c,v 1.85 2009/09/01 00:22:26 jinmei Exp $ */
  19
  20 /*! \file */
  21
  22 #include <config.h>
  23
  24 #include <isc/magic.h>
  25 #include <isc/mem.h>
  26 #include <isc/task.h>
  27 #include <isc/timer.h>
  28 #include <isc/util.h>
  29
  30 #include <dns/acl.h>
  31 #include <dns/compress.h>
  32 #include <dns/dispatch.h>
  33 #include <dns/events.h>
  34 #include <dns/log.h>
  35 #include <dns/message.h>
  36 #include <dns/rdata.h>
  37 #include <dns/rdatastruct.h>
  38 #include <dns/request.h>
  39 #include <dns/result.h>
  40 #include <dns/tsig.h>
  41
  42 #define REQUESTMGR_MAGIC        ISC_MAGIC('R', 'q', 'u', 'M')
  43 #define VALID_REQUESTMGR(mgr)   ISC_MAGIC_VALID(mgr, REQUESTMGR_MAGIC)
  44
  45 #define REQUEST_MAGIC           ISC_MAGIC('R', 'q', 'u', '!')
  46 #define VALID_REQUEST(request)  ISC_MAGIC_VALID(request, REQUEST_MAGIC)
  47
  48 typedef ISC_LIST(dns_request_t) dns_requestlist_t;
  49
  50 #define DNS_REQUEST_NLOCKS 7
  51
  52 struct dns_requestmgr {
  53         unsigned int                    magic;
  54         isc_mutex_t                     lock;
  55         isc_mem_t                      *mctx;
  56
  57         /* locked */
  58         isc_int32_t                     eref;
  59         isc_int32_t                     iref;
  60         isc_timermgr_t                 *timermgr;
  61         isc_socketmgr_t                *socketmgr;
  62         isc_taskmgr_t                  *taskmgr;
  63         dns_dispatchmgr_t              *dispatchmgr;
  64         dns_dispatch_t                 *dispatchv4;
  65         dns_dispatch_t                 *dispatchv6;
  66         isc_boolean_t                   exiting;
  67         isc_eventlist_t                 whenshutdown;
  68         unsigned int                    hash;
  69         isc_mutex_t                     locks[DNS_REQUEST_NLOCKS];
  70         dns_requestlist_t               requests;
  71 };
  72
  73 struct dns_request {
  74         unsigned int                    magic;
  75         unsigned int                    hash;
  76         isc_mem_t                      *mctx;
  77         isc_int32_t                     flags;
  78         ISC_LINK(dns_request_t)         link;
  79         isc_buffer_t                   *query;
  80         isc_buffer_t                   *answer;
  81         dns_requestevent_t             *event;
  82         dns_dispatch_t                 *dispatch;
  83         dns_dispentry_t                *dispentry;
  84         isc_timer_t                    *timer;
  85         dns_requestmgr_t               *requestmgr;
  86         isc_buffer_t                   *tsig;
  87         dns_tsigkey_t                  *tsigkey;
  88         isc_event_t                     ctlevent;
  89         isc_boolean_t                   canceling; /* ctlevent outstanding */
  90         isc_sockaddr_t                  destaddr;
  91         unsigned int                    udpcount;
  92 };
  93
  94 #define DNS_REQUEST_F_CONNECTING 0x0001
  95 #define DNS_REQUEST_F_SENDING 0x0002
  96 #define DNS_REQUEST_F_CANCELED 0x0004   /*%< ctlevent received, or otherwise
  97                                            synchronously canceled */
  98 #define DNS_REQUEST_F_TIMEDOUT 0x0008   /*%< canceled due to a timeout */
  99 #define DNS_REQUEST_F_TCP 0x0010        /*%< This request used TCP */
 100 #define DNS_REQUEST_CANCELED(r) \
 101         (((r)->flags & DNS_REQUEST_F_CANCELED) != 0)
 102 #define DNS_REQUEST_CONNECTING(r) \
 103         (((r)->flags & DNS_REQUEST_F_CONNECTING) != 0)
 104 #define DNS_REQUEST_SENDING(r) \
 105         (((r)->flags & DNS_REQUEST_F_SENDING) != 0)
 106 #define DNS_REQUEST_TIMEDOUT(r) \
 107         (((r)->flags & DNS_REQUEST_F_TIMEDOUT) != 0)
 108
 109
 110 /***
 111  *** Forward
 112  ***/
 113
 114 static void mgr_destroy(dns_requestmgr_t *requestmgr);
 115 static void mgr_shutdown(dns_requestmgr_t *requestmgr);
 116 static unsigned int mgr_gethash(dns_requestmgr_t *requestmgr);
 117 static void send_shutdown_events(dns_requestmgr_t *requestmgr);
 118
 119 static isc_result_t req_render(dns_message_t *message, isc_buffer_t **buffer,
 120                                unsigned int options, isc_mem_t *mctx);
 121 static void req_senddone(isc_task_t *task, isc_event_t *event);
 122 static void req_response(isc_task_t *task, isc_event_t *event);
 123 static void req_timeout(isc_task_t *task, isc_event_t *event);
 124 static isc_socket_t * req_getsocket(dns_request_t *request);
 125 static void req_connected(isc_task_t *task, isc_event_t *event);
 126 static void req_sendevent(dns_request_t *request, isc_result_t result);
 127 static void req_cancel(dns_request_t *request);
 128 static void req_destroy(dns_request_t *request);
 129 static void req_log(int level, const char *fmt, ...) ISC_FORMAT_PRINTF(2, 3);
 130 static void do_cancel(isc_task_t *task, isc_event_t *event);
 131
 132 /***
 133  *** Public
 134  ***/
 135
 136 isc_result_t
 137 dns_requestmgr_create(isc_mem_t *mctx,
 138                       isc_timermgr_t *timermgr,
 139                       isc_socketmgr_t *socketmgr,
 140                       isc_taskmgr_t *taskmgr,
 141                       dns_dispatchmgr_t *dispatchmgr,
 142                       dns_dispatch_t *dispatchv4,
 143                       dns_dispatch_t *dispatchv6,
 144                       dns_requestmgr_t **requestmgrp)
 145 {
 146         dns_requestmgr_t *requestmgr;
 147         isc_socket_t *socket;
 148         isc_result_t result;
 149         int i;
 150         unsigned int dispattr;
 151
 152         req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_create");
 153
 154         REQUIRE(requestmgrp != NULL && *requestmgrp == NULL);
 155         REQUIRE(timermgr != NULL);
 156         REQUIRE(socketmgr != NULL);
 157         REQUIRE(taskmgr != NULL);
 158         REQUIRE(dispatchmgr != NULL);
 159         UNUSED(socket);
 160         if (dispatchv4 != NULL) {
 161                 dispattr = dns_dispatch_getattributes(dispatchv4);
 162                 REQUIRE((dispattr & DNS_DISPATCHATTR_UDP) != 0);
 163         }
 164         if (dispatchv6 != NULL) {
 165                 dispattr = dns_dispatch_getattributes(dispatchv6);
 166                 REQUIRE((dispattr & DNS_DISPATCHATTR_UDP) != 0);
 167         }
 168
 169         requestmgr = isc_mem_get(mctx, sizeof(*requestmgr));
 170         if (requestmgr == NULL)
 171                 return (ISC_R_NOMEMORY);
 172
 173         result = isc_mutex_init(&requestmgr->lock);
 174         if (result != ISC_R_SUCCESS) {
 175                 isc_mem_put(mctx, requestmgr, sizeof(*requestmgr));
 176                 return (result);
 177         }
 178         for (i = 0; i < DNS_REQUEST_NLOCKS; i++) {
 179                 result = isc_mutex_init(&requestmgr->locks[i]);
 180                 if (result != ISC_R_SUCCESS) {
 181                         while (--i >= 0)
 182                                 DESTROYLOCK(&requestmgr->locks[i]);
 183                         DESTROYLOCK(&requestmgr->lock);
 184                         isc_mem_put(mctx, requestmgr, sizeof(*requestmgr));
 185                         return (result);
 186                 }
 187         }
 188         requestmgr->timermgr = timermgr;
 189         requestmgr->socketmgr = socketmgr;
 190         requestmgr->taskmgr = taskmgr;
 191         requestmgr->dispatchmgr = dispatchmgr;
 192         requestmgr->dispatchv4 = NULL;
 193         if (dispatchv4 != NULL)
 194                 dns_dispatch_attach(dispatchv4, &requestmgr->dispatchv4);
 195         requestmgr->dispatchv6 = NULL;
 196         if (dispatchv6 != NULL)
 197                 dns_dispatch_attach(dispatchv6, &requestmgr->dispatchv6);
 198         requestmgr->mctx = NULL;
 199         isc_mem_attach(mctx, &requestmgr->mctx);
 200         requestmgr->eref = 1;   /* implicit attach */
 201         requestmgr->iref = 0;
 202         ISC_LIST_INIT(requestmgr->whenshutdown);
 203         ISC_LIST_INIT(requestmgr->requests);
 204         requestmgr->exiting = ISC_FALSE;
 205         requestmgr->hash = 0;
 206         requestmgr->magic = REQUESTMGR_MAGIC;
 207
 208         req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_create: %p", requestmgr);
 209
 210         *requestmgrp = requestmgr;
 211         return (ISC_R_SUCCESS);
 212 }
 213
 214 void
 215 dns_requestmgr_whenshutdown(dns_requestmgr_t *requestmgr, isc_task_t *task,
 216                             isc_event_t **eventp)
 217 {
 218         isc_task_t *clone;
 219         isc_event_t *event;
 220
 221         req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_whenshutdown");
 222
 223         REQUIRE(VALID_REQUESTMGR(requestmgr));
 224         REQUIRE(eventp != NULL);
 225
 226         event = *eventp;
 227         *eventp = NULL;
 228
 229         LOCK(&requestmgr->lock);
 230
 231         if (requestmgr->exiting) {
 232                 /*
 233                  * We're already shutdown.  Send the event.
 234                  */
 235                 event->ev_sender = requestmgr;
 236                 isc_task_send(task, &event);
 237         } else {
 238                 clone = NULL;
 239                 isc_task_attach(task, &clone);
 240                 event->ev_sender = clone;
 241                 ISC_LIST_APPEND(requestmgr->whenshutdown, event, ev_link);
 242         }
 243         UNLOCK(&requestmgr->lock);
 244 }
 245
 246 void
 247 dns_requestmgr_shutdown(dns_requestmgr_t *requestmgr) {
 248
 249         REQUIRE(VALID_REQUESTMGR(requestmgr));
 250
 251         req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_shutdown: %p", requestmgr);
 252
 253         LOCK(&requestmgr->lock);
 254         mgr_shutdown(requestmgr);
 255         UNLOCK(&requestmgr->lock);
 256 }
 257
 258 static void
 259 mgr_shutdown(dns_requestmgr_t *requestmgr) {
 260         dns_request_t *request;
 261
 262         /*
 263          * Caller holds lock.
 264          */
 265         if (!requestmgr->exiting) {
 266                 requestmgr->exiting = ISC_TRUE;
 267                 for (request = ISC_LIST_HEAD(requestmgr->requests);
 268                      request != NULL;
 269                      request = ISC_LIST_NEXT(request, link)) {
 270                         dns_request_cancel(request);
 271                 }
 272                 if (requestmgr->iref == 0) {
 273                         INSIST(ISC_LIST_EMPTY(requestmgr->requests));
 274                         send_shutdown_events(requestmgr);
 275                 }
 276         }
 277 }
 278
 279 static void
 280 requestmgr_attach(dns_requestmgr_t *source, dns_requestmgr_t **targetp) {
 281
 282         /*
 283          * Locked by caller.
 284          */
 285
 286         REQUIRE(VALID_REQUESTMGR(source));
 287         REQUIRE(targetp != NULL && *targetp == NULL);
 288
 289         REQUIRE(!source->exiting);
 290
 291         source->iref++;
 292         *targetp = source;
 293
 294         req_log(ISC_LOG_DEBUG(3), "requestmgr_attach: %p: eref %d iref %d",
 295                 source, source->eref, source->iref);
 296 }
 297
 298 static void
 299 requestmgr_detach(dns_requestmgr_t **requestmgrp) {
 300         dns_requestmgr_t *requestmgr;
 301         isc_boolean_t need_destroy = ISC_FALSE;
 302
 303         REQUIRE(requestmgrp != NULL);
 304         requestmgr = *requestmgrp;
 305         REQUIRE(VALID_REQUESTMGR(requestmgr));
 306
 307         *requestmgrp = NULL;
 308         LOCK(&requestmgr->lock);
 309         INSIST(requestmgr->iref > 0);
 310         requestmgr->iref--;
 311
 312         req_log(ISC_LOG_DEBUG(3), "requestmgr_detach: %p: eref %d iref %d",
 313                 requestmgr, requestmgr->eref, requestmgr->iref);
 314
 315         if (requestmgr->iref == 0 && requestmgr->exiting) {
 316                 INSIST(ISC_LIST_HEAD(requestmgr->requests) == NULL);
 317                 send_shutdown_events(requestmgr);
 318                 if (requestmgr->eref == 0)
 319                         need_destroy = ISC_TRUE;
 320         }
 321         UNLOCK(&requestmgr->lock);
 322
 323         if (need_destroy)
 324                 mgr_destroy(requestmgr);
 325 }
 326
 327 void
 328 dns_requestmgr_attach(dns_requestmgr_t *source, dns_requestmgr_t **targetp) {
 329
 330         REQUIRE(VALID_REQUESTMGR(source));
 331         REQUIRE(targetp != NULL && *targetp == NULL);
 332         REQUIRE(!source->exiting);
 333
 334         LOCK(&source->lock);
 335         source->eref++;
 336         *targetp = source;
 337         UNLOCK(&source->lock);
 338
 339         req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_attach: %p: eref %d iref %d",
 340                 source, source->eref, source->iref);
 341 }
 342
 343 void
 344 dns_requestmgr_detach(dns_requestmgr_t **requestmgrp) {
 345         dns_requestmgr_t *requestmgr;
 346         isc_boolean_t need_destroy = ISC_FALSE;
 347
 348         REQUIRE(requestmgrp != NULL);
 349         requestmgr = *requestmgrp;
 350         REQUIRE(VALID_REQUESTMGR(requestmgr));
 351
 352         LOCK(&requestmgr->lock);
 353         INSIST(requestmgr->eref > 0);
 354         requestmgr->eref--;
 355
 356         req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_detach: %p: eref %d iref %d",
 357                 requestmgr, requestmgr->eref, requestmgr->iref);
 358
 359         if (requestmgr->eref == 0 && requestmgr->iref == 0) {
 360                 INSIST(requestmgr->exiting &&
 361                        ISC_LIST_HEAD(requestmgr->requests) == NULL);
 362                 need_destroy = ISC_TRUE;
 363         }
 364         UNLOCK(&requestmgr->lock);
 365
 366         if (need_destroy)
 367                 mgr_destroy(requestmgr);
 368
 369         *requestmgrp = NULL;
 370 }
 371
 372 static void
 373 send_shutdown_events(dns_requestmgr_t *requestmgr) {
 374         isc_event_t *event, *next_event;
 375         isc_task_t *etask;
 376
 377         req_log(ISC_LOG_DEBUG(3), "send_shutdown_events: %p", requestmgr);
 378
 379         /*
 380          * Caller must be holding the manager lock.
 381          */
 382         for (event = ISC_LIST_HEAD(requestmgr->whenshutdown);
 383              event != NULL;
 384              event = next_event) {
 385                 next_event = ISC_LIST_NEXT(event, ev_link);
 386                 ISC_LIST_UNLINK(requestmgr->whenshutdown, event, ev_link);
 387                 etask = event->ev_sender;
 388                 event->ev_sender = requestmgr;
 389                 isc_task_sendanddetach(&etask, &event);
 390         }
 391 }
 392
 393 static void
 394 mgr_destroy(dns_requestmgr_t *requestmgr) {
 395         int i;
 396         isc_mem_t *mctx;
 397
 398         req_log(ISC_LOG_DEBUG(3), "mgr_destroy");
 399
 400         REQUIRE(requestmgr->eref == 0);
 401         REQUIRE(requestmgr->iref == 0);
 402
 403         DESTROYLOCK(&requestmgr->lock);
 404         for (i = 0; i < DNS_REQUEST_NLOCKS; i++)
 405                 DESTROYLOCK(&requestmgr->locks[i]);
 406         if (requestmgr->dispatchv4 != NULL)
 407                 dns_dispatch_detach(&requestmgr->dispatchv4);
 408         if (requestmgr->dispatchv6 != NULL)
 409                 dns_dispatch_detach(&requestmgr->dispatchv6);
 410         requestmgr->magic = 0;
 411         mctx = requestmgr->mctx;
 412         isc_mem_put(mctx, requestmgr, sizeof(*requestmgr));
 413         isc_mem_detach(&mctx);
 414 }
 415
 416 static unsigned int
 417 mgr_gethash(dns_requestmgr_t *requestmgr) {
 418         req_log(ISC_LOG_DEBUG(3), "mgr_gethash");
 419         /*
 420          * Locked by caller.
 421          */
 422         requestmgr->hash++;
 423         return (requestmgr->hash % DNS_REQUEST_NLOCKS);
 424 }
 425
 426 static inline isc_result_t
 427 req_send(dns_request_t *request, isc_task_t *task, isc_sockaddr_t *address) {
 428         isc_region_t r;
 429         isc_socket_t *socket;
 430         isc_result_t result;
 431         unsigned int dispattr;
 432
 433         req_log(ISC_LOG_DEBUG(3), "req_send: request %p", request);
 434
 435         REQUIRE(VALID_REQUEST(request));
 436         dispattr = dns_dispatch_getattributes(request->dispatch);
 437         socket = req_getsocket(request);
 438         isc_buffer_usedregion(request->query, &r);
 439         /*
 440          * We could connect the socket when we are using an exclusive dispatch
 441          * as we do in resolver.c, but we prefer implementation simplicity
 442          * at this moment.
 443          */
 444         result = isc_socket_sendto(socket, &r, task, req_senddone,
 445                                   request, address, NULL);
 446         if (result == ISC_R_SUCCESS)
 447                 request->flags |= DNS_REQUEST_F_SENDING;
 448         return (result);
 449 }
 450
 451 static isc_result_t
 452 new_request(isc_mem_t *mctx, dns_request_t **requestp)
 453 {
 454         dns_request_t *request;
 455
 456         request = isc_mem_get(mctx, sizeof(*request));
 457         if (request == NULL)
 458                 return (ISC_R_NOMEMORY);
 459
 460         /*
 461          * Zero structure.
 462          */
 463         request->magic = 0;
 464         request->mctx = NULL;
 465         request->flags = 0;
 466         ISC_LINK_INIT(request, link);
 467         request->query = NULL;
 468         request->answer = NULL;
 469         request->event = NULL;
 470         request->dispatch = NULL;
 471         request->dispentry = NULL;
 472         request->timer = NULL;
 473         request->requestmgr = NULL;
 474         request->tsig = NULL;
 475         request->tsigkey = NULL;
 476         ISC_EVENT_INIT(&request->ctlevent, sizeof(request->ctlevent), 0, NULL,
 477                        DNS_EVENT_REQUESTCONTROL, do_cancel, request, NULL,
 478                        NULL, NULL);
 479         request->canceling = ISC_FALSE;
 480         request->udpcount = 0;
 481
 482         isc_mem_attach(mctx, &request->mctx);
 483
 484         request->magic = REQUEST_MAGIC;
 485         *requestp = request;
 486         return (ISC_R_SUCCESS);
 487 }
 488
 489
 490 static isc_boolean_t
 491 isblackholed(dns_dispatchmgr_t *dispatchmgr, isc_sockaddr_t *destaddr) {
 492         dns_acl_t *blackhole;
 493         isc_netaddr_t netaddr;
 494         int match;
 495         isc_boolean_t drop = ISC_FALSE;
 496         char netaddrstr[ISC_NETADDR_FORMATSIZE];
 497
 498         blackhole = dns_dispatchmgr_getblackhole(dispatchmgr);
 499         if (blackhole != NULL) {
 500                 isc_netaddr_fromsockaddr(&netaddr, destaddr);
 501                 if (dns_acl_match(&netaddr, NULL, blackhole,
 502                                   NULL, &match, NULL) == ISC_R_SUCCESS &&
 503                     match > 0)
 504                         drop = ISC_TRUE;
 505         }
 506         if (drop) {
 507                 isc_netaddr_format(&netaddr, netaddrstr, sizeof(netaddrstr));
 508                 req_log(ISC_LOG_DEBUG(10), "blackholed address %s", netaddrstr);
 509         }
 510         return (drop);
 511 }
 512
 513 static isc_result_t
 514 create_tcp_dispatch(dns_requestmgr_t *requestmgr, isc_sockaddr_t *srcaddr,
 515                     isc_sockaddr_t *destaddr, dns_dispatch_t **dispatchp)
 516 {
 517         isc_result_t result;
 518         isc_socket_t *socket = NULL;
 519         isc_sockaddr_t src;
 520         unsigned int attrs;
 521         isc_sockaddr_t bind_any;
 522
 523         result = isc_socket_create(requestmgr->socketmgr,
 524                                    isc_sockaddr_pf(destaddr),
 525                                    isc_sockettype_tcp, &socket);
 526         if (result != ISC_R_SUCCESS)
 527                 return (result);
 528 #ifndef BROKEN_TCP_BIND_BEFORE_CONNECT
 529         if (srcaddr == NULL) {
 530                 isc_sockaddr_anyofpf(&bind_any,
 531                                      isc_sockaddr_pf(destaddr));
 532                 result = isc_socket_bind(socket, &bind_any, 0);
 533         } else {
 534                 src = *srcaddr;
 535                 isc_sockaddr_setport(&src, 0);
 536                 result = isc_socket_bind(socket, &src, 0);
 537         }
 538         if (result != ISC_R_SUCCESS)
 539                 goto cleanup;
 540 #endif
 541         attrs = 0;
 542         attrs |= DNS_DISPATCHATTR_TCP;
 543         attrs |= DNS_DISPATCHATTR_PRIVATE;
 544         if (isc_sockaddr_pf(destaddr) == AF_INET)
 545                 attrs |= DNS_DISPATCHATTR_IPV4;
 546         else
 547                 attrs |= DNS_DISPATCHATTR_IPV6;
 548         attrs |= DNS_DISPATCHATTR_MAKEQUERY;
 549         result = dns_dispatch_createtcp(requestmgr->dispatchmgr,
 550                                         socket, requestmgr->taskmgr,
 551                                         4096, 2, 1, 1, 3, attrs,
 552                                         dispatchp);
 553 cleanup:
 554         isc_socket_detach(&socket);
 555         return (result);
 556 }
 557
 558 static isc_result_t
 559 find_udp_dispatch(dns_requestmgr_t *requestmgr, isc_sockaddr_t *srcaddr,
 560                   isc_sockaddr_t *destaddr, dns_dispatch_t **dispatchp)
 561 {
 562         dns_dispatch_t *disp = NULL;
 563         unsigned int attrs, attrmask;
 564
 565         if (srcaddr == NULL) {
 566                 switch (isc_sockaddr_pf(destaddr)) {
 567                 case PF_INET:
 568                         disp = requestmgr->dispatchv4;
 569                         break;
 570
 571                 case PF_INET6:
 572                         disp = requestmgr->dispatchv6;
 573                         break;
 574
 575                 default:
 576                         return (ISC_R_NOTIMPLEMENTED);
 577                 }
 578                 if (disp == NULL)
 579                         return (ISC_R_FAMILYNOSUPPORT);
 580                 dns_dispatch_attach(disp, dispatchp);
 581                 return (ISC_R_SUCCESS);
 582         }
 583         attrs = 0;
 584         attrs |= DNS_DISPATCHATTR_UDP;
 585         switch (isc_sockaddr_pf(srcaddr)) {
 586         case PF_INET:
 587                 attrs |= DNS_DISPATCHATTR_IPV4;
 588                 break;
 589
 590         case PF_INET6:
 591                 attrs |= DNS_DISPATCHATTR_IPV6;
 592                 break;
 593
 594         default:
 595                 return (ISC_R_NOTIMPLEMENTED);
 596         }
 597         attrmask = 0;
 598         attrmask |= DNS_DISPATCHATTR_UDP;
 599         attrmask |= DNS_DISPATCHATTR_TCP;
 600         attrmask |= DNS_DISPATCHATTR_IPV4;
 601         attrmask |= DNS_DISPATCHATTR_IPV6;
 602         return (dns_dispatch_getudp(requestmgr->dispatchmgr,
 603                                     requestmgr->socketmgr,
 604                                     requestmgr->taskmgr,
 605                                     srcaddr, 4096,
 606                                     1000, 32768, 16411, 16433,
 607                                     attrs, attrmask,
 608                                     dispatchp));
 609 }
 610
 611 static isc_result_t
 612 get_dispatch(isc_boolean_t tcp, dns_requestmgr_t *requestmgr,
 613              isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 614              dns_dispatch_t **dispatchp)
 615 {
 616         isc_result_t result;
 617         if (tcp)
 618                 result = create_tcp_dispatch(requestmgr, srcaddr,
 619                                              destaddr, dispatchp);
 620         else
 621                 result = find_udp_dispatch(requestmgr, srcaddr,
 622                                            destaddr, dispatchp);
 623         return (result);
 624 }
 625
 626 static isc_result_t
 627 set_timer(isc_timer_t *timer, unsigned int timeout, unsigned int udpresend) {
 628         isc_time_t expires;
 629         isc_interval_t interval;
 630         isc_result_t result;
 631         isc_timertype_t timertype;
 632
 633         isc_interval_set(&interval, timeout, 0);
 634         result = isc_time_nowplusinterval(&expires, &interval);
 635         isc_interval_set(&interval, udpresend, 0);
 636
 637         timertype = udpresend != 0 ? isc_timertype_limited : isc_timertype_once;
 638         if (result == ISC_R_SUCCESS)
 639                 result = isc_timer_reset(timer, timertype, &expires,
 640                                          &interval, ISC_FALSE);
 641         return (result);
 642 }
 643
 644 isc_result_t
 645 dns_request_createraw(dns_requestmgr_t *requestmgr, isc_buffer_t *msgbuf,
 646                       isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 647                       unsigned int options, unsigned int timeout,
 648                       isc_task_t *task, isc_taskaction_t action, void *arg,
 649                       dns_request_t **requestp)
 650 {
 651         return(dns_request_createraw3(requestmgr, msgbuf, srcaddr, destaddr,
 652                                       options, timeout, 0, 0, task, action,
 653                                       arg, requestp));
 654 }
 655
 656 isc_result_t
 657 dns_request_createraw2(dns_requestmgr_t *requestmgr, isc_buffer_t *msgbuf,
 658                        isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 659                        unsigned int options, unsigned int timeout,
 660                        unsigned int udptimeout, isc_task_t *task,
 661                        isc_taskaction_t action, void *arg,
 662                        dns_request_t **requestp)
 663 {
 664         unsigned int udpretries = 0;
 665
 666         if (udptimeout != 0)
 667                 udpretries = timeout / udptimeout;
 668
 669         return (dns_request_createraw3(requestmgr, msgbuf, srcaddr, destaddr,
 670                                        options, timeout, udptimeout,
 671                                        udpretries, task, action, arg,
 672                                        requestp));
 673 }
 674
 675 isc_result_t
 676 dns_request_createraw3(dns_requestmgr_t *requestmgr, isc_buffer_t *msgbuf,
 677                        isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 678                        unsigned int options, unsigned int timeout,
 679                        unsigned int udptimeout, unsigned int udpretries,
 680                        isc_task_t *task, isc_taskaction_t action, void *arg,
 681                        dns_request_t **requestp)
 682 {
 683         dns_request_t *request = NULL;
 684         isc_task_t *tclone = NULL;
 685         isc_socket_t *socket = NULL;
 686         isc_result_t result;
 687         isc_mem_t *mctx;
 688         dns_messageid_t id;
 689         isc_boolean_t tcp = ISC_FALSE;
 690         isc_region_t r;
 691
 692         REQUIRE(VALID_REQUESTMGR(requestmgr));
 693         REQUIRE(msgbuf != NULL);
 694         REQUIRE(destaddr != NULL);
 695         REQUIRE(task != NULL);
 696         REQUIRE(action != NULL);
 697         REQUIRE(requestp != NULL && *requestp == NULL);
 698         REQUIRE(timeout > 0);
 699         if (srcaddr != NULL)
 700                 REQUIRE(isc_sockaddr_pf(srcaddr) == isc_sockaddr_pf(destaddr));
 701
 702         mctx = requestmgr->mctx;
 703
 704         req_log(ISC_LOG_DEBUG(3), "dns_request_createraw");
 705
 706         if (isblackholed(requestmgr->dispatchmgr, destaddr))
 707                 return (DNS_R_BLACKHOLED);
 708
 709         request = NULL;
 710         result = new_request(mctx, &request);
 711         if (result != ISC_R_SUCCESS)
 712                 return (result);
 713
 714         if (udptimeout == 0 && udpretries != 0) {
 715                 udptimeout = timeout / (udpretries + 1);
 716                 if (udptimeout == 0)
 717                         udptimeout = 1;
 718         }
 719         request->udpcount = udpretries;
 720
 721         /*
 722          * Create timer now.  We will set it below once.
 723          */
 724         result = isc_timer_create(requestmgr->timermgr, isc_timertype_inactive,
 725                                   NULL, NULL, task, req_timeout, request,
 726                                   &request->timer);
 727         if (result != ISC_R_SUCCESS)
 728                 goto cleanup;
 729
 730         request->event = (dns_requestevent_t *)
 731                 isc_event_allocate(mctx, task, DNS_EVENT_REQUESTDONE,
 732                                    action, arg, sizeof(dns_requestevent_t));
 733         if (request->event == NULL) {
 734                 result = ISC_R_NOMEMORY;
 735                 goto cleanup;
 736         }
 737         isc_task_attach(task, &tclone);
 738         request->event->ev_sender = task;
 739         request->event->request = request;
 740         request->event->result = ISC_R_FAILURE;
 741
 742         isc_buffer_usedregion(msgbuf, &r);
 743         if (r.length < DNS_MESSAGE_HEADERLEN || r.length > 65535) {
 744                 result = DNS_R_FORMERR;
 745                 goto cleanup;
 746         }
 747
 748         if ((options & DNS_REQUESTOPT_TCP) != 0 || r.length > 512)
 749                 tcp = ISC_TRUE;
 750
 751         result = get_dispatch(tcp, requestmgr, srcaddr, destaddr,
 752                               &request->dispatch);
 753         if (result != ISC_R_SUCCESS)
 754                 goto cleanup;
 755
 756         result = dns_dispatch_addresponse2(request->dispatch, destaddr, task,
 757                                            req_response, request, &id,
 758                                            &request->dispentry,
 759                                            requestmgr->socketmgr);
 760         if (result != ISC_R_SUCCESS)
 761                 goto cleanup;
 762
 763         socket = req_getsocket(request);
 764         INSIST(socket != NULL);
 765
 766         result = isc_buffer_allocate(mctx, &request->query,
 767                                      r.length + (tcp ? 2 : 0));
 768         if (result != ISC_R_SUCCESS)
 769                 goto cleanup;
 770         if (tcp)
 771                 isc_buffer_putuint16(request->query, (isc_uint16_t)r.length);
 772         result = isc_buffer_copyregion(request->query, &r);
 773         if (result != ISC_R_SUCCESS)
 774                 goto cleanup;
 775
 776         /* Add message ID. */
 777         isc_buffer_usedregion(request->query, &r);
 778         if (tcp)
 779                 isc_region_consume(&r, 2);
 780         r.base[0] = (id>>8) & 0xff;
 781         r.base[1] = id & 0xff;
 782
 783         LOCK(&requestmgr->lock);
 784         if (requestmgr->exiting) {
 785                 UNLOCK(&requestmgr->lock);
 786                 result = ISC_R_SHUTTINGDOWN;
 787                 goto cleanup;
 788         }
 789         requestmgr_attach(requestmgr, &request->requestmgr);
 790         request->hash = mgr_gethash(requestmgr);
 791         ISC_LIST_APPEND(requestmgr->requests, request, link);
 792         UNLOCK(&requestmgr->lock);
 793
 794         result = set_timer(request->timer, timeout, tcp ? 0 : udptimeout);
 795         if (result != ISC_R_SUCCESS)
 796                 goto unlink;
 797
 798         request->destaddr = *destaddr;
 799         if (tcp) {
 800                 result = isc_socket_connect(socket, destaddr, task,
 801                                             req_connected, request);
 802                 if (result != ISC_R_SUCCESS)
 803                         goto unlink;
 804                 request->flags |= DNS_REQUEST_F_CONNECTING|DNS_REQUEST_F_TCP;
 805         } else {
 806                 result = req_send(request, task, destaddr);
 807                 if (result != ISC_R_SUCCESS)
 808                         goto unlink;
 809         }
 810
 811         req_log(ISC_LOG_DEBUG(3), "dns_request_createraw: request %p",
 812                 request);
 813         *requestp = request;
 814         return (ISC_R_SUCCESS);
 815
 816  unlink:
 817         LOCK(&requestmgr->lock);
 818         ISC_LIST_UNLINK(requestmgr->requests, request, link);
 819         UNLOCK(&requestmgr->lock);
 820
 821  cleanup:
 822         if (tclone != NULL)
 823                 isc_task_detach(&tclone);
 824         req_destroy(request);
 825         req_log(ISC_LOG_DEBUG(3), "dns_request_createraw: failed %s",
 826                 dns_result_totext(result));
 827         return (result);
 828 }
 829
 830 isc_result_t
 831 dns_request_create(dns_requestmgr_t *requestmgr, dns_message_t *message,
 832                    isc_sockaddr_t *address, unsigned int options,
 833                    dns_tsigkey_t *key,
 834                    unsigned int timeout, isc_task_t *task,
 835                    isc_taskaction_t action, void *arg,
 836                    dns_request_t **requestp)
 837 {
 838         return (dns_request_createvia3(requestmgr, message, NULL, address,
 839                                        options, key, timeout, 0, 0, task,
 840                                        action, arg, requestp));
 841 }
 842
 843 isc_result_t
 844 dns_request_createvia(dns_requestmgr_t *requestmgr, dns_message_t *message,
 845                       isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 846                       unsigned int options, dns_tsigkey_t *key,
 847                       unsigned int timeout, isc_task_t *task,
 848                       isc_taskaction_t action, void *arg,
 849                       dns_request_t **requestp)
 850 {
 851         return(dns_request_createvia3(requestmgr, message, srcaddr, destaddr,
 852                                       options, key, timeout, 0, 0, task,
 853                                       action, arg, requestp));
 854 }
 855
 856 isc_result_t
 857 dns_request_createvia2(dns_requestmgr_t *requestmgr, dns_message_t *message,
 858                        isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 859                        unsigned int options, dns_tsigkey_t *key,
 860                        unsigned int timeout, unsigned int udptimeout,
 861                        isc_task_t *task, isc_taskaction_t action, void *arg,
 862                        dns_request_t **requestp)
 863 {
 864         unsigned int udpretries = 0;
 865
 866         if (udptimeout != 0)
 867                 udpretries = timeout / udptimeout;
 868         return (dns_request_createvia3(requestmgr, message, srcaddr, destaddr,
 869                                        options, key, timeout, udptimeout,
 870                                        udpretries, task, action, arg,
 871                                        requestp));
 872 }
 873
 874 isc_result_t
 875 dns_request_createvia3(dns_requestmgr_t *requestmgr, dns_message_t *message,
 876                        isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
 877                        unsigned int options, dns_tsigkey_t *key,
 878                        unsigned int timeout, unsigned int udptimeout,
 879                        unsigned int udpretries, isc_task_t *task,
 880                        isc_taskaction_t action, void *arg,
 881                        dns_request_t **requestp)
 882 {
 883         dns_request_t *request = NULL;
 884         isc_task_t *tclone = NULL;
 885         isc_socket_t *socket = NULL;
 886         isc_result_t result;
 887         isc_mem_t *mctx;
 888         dns_messageid_t id;
 889         isc_boolean_t tcp;
 890         isc_boolean_t setkey = ISC_TRUE;
 891
 892         REQUIRE(VALID_REQUESTMGR(requestmgr));
 893         REQUIRE(message != NULL);
 894         REQUIRE(destaddr != NULL);
 895         REQUIRE(task != NULL);
 896         REQUIRE(action != NULL);
 897         REQUIRE(requestp != NULL && *requestp == NULL);
 898         REQUIRE(timeout > 0);
 899         if (srcaddr != NULL)
 900                 REQUIRE(isc_sockaddr_pf(srcaddr) == isc_sockaddr_pf(destaddr));
 901
 902         mctx = requestmgr->mctx;
 903
 904         req_log(ISC_LOG_DEBUG(3), "dns_request_createvia");
 905
 906         if (isblackholed(requestmgr->dispatchmgr, destaddr))
 907                 return (DNS_R_BLACKHOLED);
 908
 909         request = NULL;
 910         result = new_request(mctx, &request);
 911         if (result != ISC_R_SUCCESS)
 912                 return (result);
 913
 914         if (udptimeout == 0 && udpretries != 0) {
 915                 udptimeout = timeout / (udpretries + 1);
 916                 if (udptimeout == 0)
 917                         udptimeout = 1;
 918         }
 919         request->udpcount = udpretries;
 920
 921         /*
 922          * Create timer now.  We will set it below once.
 923          */
 924         result = isc_timer_create(requestmgr->timermgr, isc_timertype_inactive,
 925                                   NULL, NULL, task, req_timeout, request,
 926                                   &request->timer);
 927         if (result != ISC_R_SUCCESS)
 928                 goto cleanup;
 929
 930         request->event = (dns_requestevent_t *)
 931                 isc_event_allocate(mctx, task, DNS_EVENT_REQUESTDONE,
 932                                    action, arg, sizeof(dns_requestevent_t));
 933         if (request->event == NULL) {
 934                 result = ISC_R_NOMEMORY;
 935                 goto cleanup;
 936         }
 937         isc_task_attach(task, &tclone);
 938         request->event->ev_sender = task;
 939         request->event->request = request;
 940         request->event->result = ISC_R_FAILURE;
 941         if (key != NULL)
 942                 dns_tsigkey_attach(key, &request->tsigkey);
 943
 944  use_tcp:
 945         tcp = ISC_TF((options & DNS_REQUESTOPT_TCP) != 0);
 946         result = get_dispatch(tcp, requestmgr, srcaddr, destaddr,
 947                               &request->dispatch);
 948         if (result != ISC_R_SUCCESS)
 949                 goto cleanup;
 950
 951         result = dns_dispatch_addresponse2(request->dispatch, destaddr, task,
 952                                            req_response, request, &id,
 953                                            &request->dispentry,
 954                                            requestmgr->socketmgr);
 955         if (result != ISC_R_SUCCESS)
 956                 goto cleanup;
 957         socket = req_getsocket(request);
 958         INSIST(socket != NULL);
 959
 960         message->id = id;
 961         if (setkey) {
 962                 result = dns_message_settsigkey(message, request->tsigkey);
 963                 if (result != ISC_R_SUCCESS)
 964                         goto cleanup;
 965         }
 966         result = req_render(message, &request->query, options, mctx);
 967         if (result == DNS_R_USETCP &&
 968             (options & DNS_REQUESTOPT_TCP) == 0) {
 969                 /*
 970                  * Try again using TCP.
 971                  */
 972                 dns_message_renderreset(message);
 973                 dns_dispatch_removeresponse(&request->dispentry, NULL);
 974                 dns_dispatch_detach(&request->dispatch);
 975                 socket = NULL;
 976                 options |= DNS_REQUESTOPT_TCP;
 977                 setkey = ISC_FALSE;
 978                 goto use_tcp;
 979         }
 980         if (result != ISC_R_SUCCESS)
 981                 goto cleanup;
 982
 983         result = dns_message_getquerytsig(message, mctx, &request->tsig);
 984         if (result != ISC_R_SUCCESS)
 985                 goto cleanup;
 986
 987         LOCK(&requestmgr->lock);
 988         if (requestmgr->exiting) {
 989                 UNLOCK(&requestmgr->lock);
 990                 result = ISC_R_SHUTTINGDOWN;
 991                 goto cleanup;
 992         }
 993         requestmgr_attach(requestmgr, &request->requestmgr);
 994         request->hash = mgr_gethash(requestmgr);
 995         ISC_LIST_APPEND(requestmgr->requests, request, link);
 996         UNLOCK(&requestmgr->lock);
 997
 998         result = set_timer(request->timer, timeout, tcp ? 0 : udptimeout);
 999         if (result != ISC_R_SUCCESS)
1000                 goto unlink;
1001
1002         request->destaddr = *destaddr;
1003         if (tcp) {
1004                 result = isc_socket_connect(socket, destaddr, task,
1005                                             req_connected, request);
1006                 if (result != ISC_R_SUCCESS)
1007                         goto unlink;
1008                 request->flags |= DNS_REQUEST_F_CONNECTING|DNS_REQUEST_F_TCP;
1009         } else {
1010                 result = req_send(request, task, destaddr);
1011                 if (result != ISC_R_SUCCESS)
1012                         goto unlink;
1013         }
1014
1015         req_log(ISC_LOG_DEBUG(3), "dns_request_createvia: request %p",
1016                 request);
1017         *requestp = request;
1018         return (ISC_R_SUCCESS);
1019
1020  unlink:
1021         LOCK(&requestmgr->lock);
1022         ISC_LIST_UNLINK(requestmgr->requests, request, link);
1023         UNLOCK(&requestmgr->lock);
1024
1025  cleanup:
1026         if (tclone != NULL)
1027                 isc_task_detach(&tclone);
1028         req_destroy(request);
1029         req_log(ISC_LOG_DEBUG(3), "dns_request_createvia: failed %s",
1030                 dns_result_totext(result));
1031         return (result);
1032 }
1033
1034 static isc_result_t
1035 req_render(dns_message_t *message, isc_buffer_t **bufferp,
1036            unsigned int options, isc_mem_t *mctx)
1037 {
1038         isc_buffer_t *buf1 = NULL;
1039         isc_buffer_t *buf2 = NULL;
1040         isc_result_t result;
1041         isc_region_t r;
1042         isc_boolean_t tcp = ISC_FALSE;
1043         dns_compress_t cctx;
1044         isc_boolean_t cleanup_cctx = ISC_FALSE;
1045
1046         REQUIRE(bufferp != NULL && *bufferp == NULL);
1047
1048         req_log(ISC_LOG_DEBUG(3), "request_render");
1049
1050         /*
1051          * Create buffer able to hold largest possible message.
1052          */
1053         result = isc_buffer_allocate(mctx, &buf1, 65535);
1054         if (result != ISC_R_SUCCESS)
1055                 return (result);
1056
1057         result = dns_compress_init(&cctx, -1, mctx);
1058         if (result != ISC_R_SUCCESS)
1059                 return (result);
1060         cleanup_cctx = ISC_TRUE;
1061
1062         /*
1063          * Render message.
1064          */
1065         result = dns_message_renderbegin(message, &cctx, buf1);
1066         if (result != ISC_R_SUCCESS)
1067                 goto cleanup;
1068         result = dns_message_rendersection(message, DNS_SECTION_QUESTION, 0);
1069         if (result != ISC_R_SUCCESS)
1070                 goto cleanup;
1071         result = dns_message_rendersection(message, DNS_SECTION_ANSWER, 0);
1072         if (result != ISC_R_SUCCESS)
1073                 goto cleanup;
1074         result = dns_message_rendersection(message, DNS_SECTION_AUTHORITY, 0);
1075         if (result != ISC_R_SUCCESS)
1076                 goto cleanup;
1077         result = dns_message_rendersection(message, DNS_SECTION_ADDITIONAL, 0);
1078         if (result != ISC_R_SUCCESS)
1079                 goto cleanup;
1080         result = dns_message_renderend(message);
1081         if (result != ISC_R_SUCCESS)
1082                 goto cleanup;
1083
1084         dns_compress_invalidate(&cctx);
1085         cleanup_cctx = ISC_FALSE;
1086
1087         /*
1088          * Copy rendered message to exact sized buffer.
1089          */
1090         isc_buffer_usedregion(buf1, &r);
1091         if ((options & DNS_REQUESTOPT_TCP) != 0) {
1092                 tcp = ISC_TRUE;
1093         } else if (r.length > 512) {
1094                 result = DNS_R_USETCP;
1095                 goto cleanup;
1096         }
1097         result = isc_buffer_allocate(mctx, &buf2, r.length + (tcp ? 2 : 0));
1098         if (result != ISC_R_SUCCESS)
1099                 goto cleanup;
1100         if (tcp)
1101                 isc_buffer_putuint16(buf2, (isc_uint16_t)r.length);
1102         result = isc_buffer_copyregion(buf2, &r);
1103         if (result != ISC_R_SUCCESS)
1104                 goto cleanup;
1105
1106         /*
1107          * Cleanup and return.
1108          */
1109         isc_buffer_free(&buf1);
1110         *bufferp = buf2;
1111         return (ISC_R_SUCCESS);
1112
1113  cleanup:
1114         dns_message_renderreset(message);
1115         if (buf1 != NULL)
1116                 isc_buffer_free(&buf1);
1117         if (buf2 != NULL)
1118                 isc_buffer_free(&buf2);
1119         if (cleanup_cctx)
1120                 dns_compress_invalidate(&cctx);
1121         return (result);
1122 }
1123
1124
1125 /*
1126  * If this request is no longer waiting for events,
1127  * send the completion event.  This will ultimately
1128  * cause the request to be destroyed.
1129  *
1130  * Requires:
1131  *      'request' is locked by the caller.
1132  */
1133 static void
1134 send_if_done(dns_request_t *request, isc_result_t result) {
1135         if (!DNS_REQUEST_CONNECTING(request) &&
1136             !DNS_REQUEST_SENDING(request) &&
1137             !request->canceling)
1138                 req_sendevent(request, result);
1139 }
1140
1141 /*
1142  * Handle the control event.
1143  */
1144 static void
1145 do_cancel(isc_task_t *task, isc_event_t *event) {
1146         dns_request_t *request = event->ev_arg;
1147         UNUSED(task);
1148         INSIST(event->ev_type == DNS_EVENT_REQUESTCONTROL);
1149         LOCK(&request->requestmgr->locks[request->hash]);
1150         request->canceling = ISC_FALSE;
1151         if (!DNS_REQUEST_CANCELED(request))
1152                 req_cancel(request);
1153         send_if_done(request, ISC_R_CANCELED);
1154         UNLOCK(&request->requestmgr->locks[request->hash]);
1155 }
1156
1157 void
1158 dns_request_cancel(dns_request_t *request) {
1159         REQUIRE(VALID_REQUEST(request));
1160
1161         req_log(ISC_LOG_DEBUG(3), "dns_request_cancel: request %p", request);
1162
1163         REQUIRE(VALID_REQUEST(request));
1164
1165         LOCK(&request->requestmgr->locks[request->hash]);
1166         if (!request->canceling && !DNS_REQUEST_CANCELED(request)) {
1167                 isc_event_t *ev =  &request->ctlevent;
1168                 isc_task_send(request->event->ev_sender, &ev);
1169                 request->canceling = ISC_TRUE;
1170         }
1171         UNLOCK(&request->requestmgr->locks[request->hash]);
1172 }
1173
1174 isc_result_t
1175 dns_request_getresponse(dns_request_t *request, dns_message_t *message,
1176                         unsigned int options)
1177 {
1178         isc_result_t result;
1179
1180         REQUIRE(VALID_REQUEST(request));
1181         REQUIRE(request->answer != NULL);
1182
1183         req_log(ISC_LOG_DEBUG(3), "dns_request_getresponse: request %p",
1184                 request);
1185
1186         result = dns_message_setquerytsig(message, request->tsig);
1187         if (result != ISC_R_SUCCESS)
1188                 return (result);
1189         result = dns_message_settsigkey(message, request->tsigkey);
1190         if (result != ISC_R_SUCCESS)
1191                 return (result);
1192         result = dns_message_parse(message, request->answer, options);
1193         if (result != ISC_R_SUCCESS)
1194                 return (result);
1195         if (request->tsigkey != NULL)
1196                 result = dns_tsig_verify(request->answer, message, NULL, NULL);
1197         return (result);
1198 }
1199
1200 isc_boolean_t
1201 dns_request_usedtcp(dns_request_t *request) {
1202         REQUIRE(VALID_REQUEST(request));
1203
1204         return (ISC_TF((request->flags & DNS_REQUEST_F_TCP) != 0));
1205 }
1206
1207 void
1208 dns_request_destroy(dns_request_t **requestp) {
1209         dns_request_t *request;
1210
1211         REQUIRE(requestp != NULL && VALID_REQUEST(*requestp));
1212
1213         request = *requestp;
1214
1215         req_log(ISC_LOG_DEBUG(3), "dns_request_destroy: request %p", request);
1216
1217         LOCK(&request->requestmgr->lock);
1218         LOCK(&request->requestmgr->locks[request->hash]);
1219         ISC_LIST_UNLINK(request->requestmgr->requests, request, link);
1220         INSIST(!DNS_REQUEST_CONNECTING(request));
1221         INSIST(!DNS_REQUEST_SENDING(request));
1222         UNLOCK(&request->requestmgr->locks[request->hash]);
1223         UNLOCK(&request->requestmgr->lock);
1224
1225         /*
1226          * These should have been cleaned up by req_cancel() before
1227          * the completion event was sent.
1228          */
1229         INSIST(!ISC_LINK_LINKED(request, link));
1230         INSIST(request->dispentry == NULL);
1231         INSIST(request->dispatch == NULL);
1232         INSIST(request->timer == NULL);
1233
1234         req_destroy(request);
1235
1236         *requestp = NULL;
1237 }
1238
1239 /***
1240  *** Private: request.
1241  ***/
1242
1243 static isc_socket_t *
1244 req_getsocket(dns_request_t *request) {
1245         unsigned int dispattr;
1246         isc_socket_t *socket;
1247
1248         dispattr = dns_dispatch_getattributes(request->dispatch);
1249         if ((dispattr & DNS_DISPATCHATTR_EXCLUSIVE) != 0) {
1250                 INSIST(request->dispentry != NULL);
1251                 socket = dns_dispatch_getentrysocket(request->dispentry);
1252         } else
1253                 socket = dns_dispatch_getsocket(request->dispatch);
1254
1255         return (socket);
1256 }
1257
1258 static void
1259 req_connected(isc_task_t *task, isc_event_t *event) {
1260         isc_socketevent_t *sevent = (isc_socketevent_t *)event;
1261         isc_result_t result;
1262         dns_request_t *request = event->ev_arg;
1263
1264         REQUIRE(event->ev_type == ISC_SOCKEVENT_CONNECT);
1265         REQUIRE(VALID_REQUEST(request));
1266         REQUIRE(DNS_REQUEST_CONNECTING(request));
1267
1268         req_log(ISC_LOG_DEBUG(3), "req_connected: request %p", request);
1269
1270         LOCK(&request->requestmgr->locks[request->hash]);
1271         request->flags &= ~DNS_REQUEST_F_CONNECTING;
1272
1273         if (DNS_REQUEST_CANCELED(request)) {
1274                 /*
1275                  * Send delayed event.
1276                  */
1277                 if (DNS_REQUEST_TIMEDOUT(request))
1278                         send_if_done(request, ISC_R_TIMEDOUT);
1279                 else
1280                         send_if_done(request, ISC_R_CANCELED);
1281         } else {
1282                 dns_dispatch_starttcp(request->dispatch);
1283                 result = sevent->result;
1284                 if (result == ISC_R_SUCCESS)
1285                         result = req_send(request, task, NULL);
1286
1287                 if (result != ISC_R_SUCCESS) {
1288                         req_cancel(request);
1289                         send_if_done(request, ISC_R_CANCELED);
1290                 }
1291         }
1292         UNLOCK(&request->requestmgr->locks[request->hash]);
1293         isc_event_free(&event);
1294 }
1295
1296 static void
1297 req_senddone(isc_task_t *task, isc_event_t *event) {
1298         isc_socketevent_t *sevent = (isc_socketevent_t *)event;
1299         dns_request_t *request = event->ev_arg;
1300
1301         REQUIRE(event->ev_type == ISC_SOCKEVENT_SENDDONE);
1302         REQUIRE(VALID_REQUEST(request));
1303         REQUIRE(DNS_REQUEST_SENDING(request));
1304
1305         req_log(ISC_LOG_DEBUG(3), "req_senddone: request %p", request);
1306
1307         UNUSED(task);
1308
1309         LOCK(&request->requestmgr->locks[request->hash]);
1310         request->flags &= ~DNS_REQUEST_F_SENDING;
1311
1312         if (DNS_REQUEST_CANCELED(request)) {
1313                 /*
1314                  * Send delayed event.
1315                  */
1316                 if (DNS_REQUEST_TIMEDOUT(request))
1317                         send_if_done(request, ISC_R_TIMEDOUT);
1318                 else
1319                         send_if_done(request, ISC_R_CANCELED);
1320         } else if (sevent->result != ISC_R_SUCCESS) {
1321                         req_cancel(request);
1322                         send_if_done(request, ISC_R_CANCELED);
1323         }
1324         UNLOCK(&request->requestmgr->locks[request->hash]);
1325
1326         isc_event_free(&event);
1327 }
1328
1329 static void
1330 req_response(isc_task_t *task, isc_event_t *event) {
1331         isc_result_t result;
1332         dns_request_t *request = event->ev_arg;
1333         dns_dispatchevent_t *devent = (dns_dispatchevent_t *)event;
1334         isc_region_t r;
1335
1336         REQUIRE(VALID_REQUEST(request));
1337         REQUIRE(event->ev_type == DNS_EVENT_DISPATCH);
1338
1339         UNUSED(task);
1340
1341         req_log(ISC_LOG_DEBUG(3), "req_response: request %p: %s", request,
1342                 dns_result_totext(devent->result));
1343
1344         LOCK(&request->requestmgr->locks[request->hash]);
1345         result = devent->result;
1346         if (result != ISC_R_SUCCESS)
1347                 goto done;
1348
1349         /*
1350          * Copy buffer to request.
1351          */
1352         isc_buffer_usedregion(&devent->buffer, &r);
1353         result = isc_buffer_allocate(request->mctx, &request->answer,
1354                                      r.length);
1355         if (result != ISC_R_SUCCESS)
1356                 goto done;
1357         result = isc_buffer_copyregion(request->answer, &r);
1358         if (result != ISC_R_SUCCESS)
1359                 isc_buffer_free(&request->answer);
1360  done:
1361         /*
1362          * Cleanup.
1363          */
1364         dns_dispatch_removeresponse(&request->dispentry, &devent);
1365         req_cancel(request);
1366         /*
1367          * Send completion event.
1368          */
1369         send_if_done(request, result);
1370         UNLOCK(&request->requestmgr->locks[request->hash]);
1371 }
1372
1373 static void
1374 req_timeout(isc_task_t *task, isc_event_t *event) {
1375         dns_request_t *request = event->ev_arg;
1376         isc_result_t result;
1377
1378         REQUIRE(VALID_REQUEST(request));
1379
1380         req_log(ISC_LOG_DEBUG(3), "req_timeout: request %p", request);
1381
1382         UNUSED(task);
1383         LOCK(&request->requestmgr->locks[request->hash]);
1384         if (event->ev_type == ISC_TIMEREVENT_TICK &&
1385             request->udpcount-- != 0) {
1386                 if (! DNS_REQUEST_SENDING(request)) {
1387                         result = req_send(request, task, &request->destaddr);
1388                         if (result != ISC_R_SUCCESS) {
1389                                 req_cancel(request);
1390                                 send_if_done(request, result);
1391                         }
1392                 }
1393         } else {
1394                 request->flags |= DNS_REQUEST_F_TIMEDOUT;
1395                 req_cancel(request);
1396                 send_if_done(request, ISC_R_TIMEDOUT);
1397         }
1398         UNLOCK(&request->requestmgr->locks[request->hash]);
1399         isc_event_free(&event);
1400 }
1401
1402 static void
1403 req_sendevent(dns_request_t *request, isc_result_t result) {
1404         isc_task_t *task;
1405
1406         REQUIRE(VALID_REQUEST(request));
1407
1408         req_log(ISC_LOG_DEBUG(3), "req_sendevent: request %p", request);
1409
1410         /*
1411          * Lock held by caller.
1412          */
1413         task = request->event->ev_sender;
1414         request->event->ev_sender = request;
1415         request->event->result = result;
1416         isc_task_sendanddetach(&task, (isc_event_t **)&request->event);
1417 }
1418
1419 static void
1420 req_destroy(dns_request_t *request) {
1421         isc_mem_t *mctx;
1422
1423         REQUIRE(VALID_REQUEST(request));
1424
1425         req_log(ISC_LOG_DEBUG(3), "req_destroy: request %p", request);
1426
1427         request->magic = 0;
1428         if (request->query != NULL)
1429                 isc_buffer_free(&request->query);
1430         if (request->answer != NULL)
1431                 isc_buffer_free(&request->answer);
1432         if (request->event != NULL)
1433                 isc_event_free((isc_event_t **)&request->event);
1434         if (request->dispentry != NULL)
1435                 dns_dispatch_removeresponse(&request->dispentry, NULL);
1436         if (request->dispatch != NULL)
1437                 dns_dispatch_detach(&request->dispatch);
1438         if (request->timer != NULL)
1439                 isc_timer_detach(&request->timer);
1440         if (request->tsig != NULL)
1441                 isc_buffer_free(&request->tsig);
1442         if (request->tsigkey != NULL)
1443                 dns_tsigkey_detach(&request->tsigkey);
1444         if (request->requestmgr != NULL)
1445                 requestmgr_detach(&request->requestmgr);
1446         mctx = request->mctx;
1447         isc_mem_put(mctx, request, sizeof(*request));
1448         isc_mem_detach(&mctx);
1449 }
1450
1451 /*
1452  * Stop the current request.  Must be called from the request's task.
1453  */
1454 static void
1455 req_cancel(dns_request_t *request) {
1456         isc_socket_t *socket;
1457         unsigned int dispattr;
1458
1459         REQUIRE(VALID_REQUEST(request));
1460
1461         req_log(ISC_LOG_DEBUG(3), "req_cancel: request %p", request);
1462
1463         /*
1464          * Lock held by caller.
1465          */
1466         request->flags |= DNS_REQUEST_F_CANCELED;
1467
1468         if (request->timer != NULL)
1469                 isc_timer_detach(&request->timer);
1470         dispattr = dns_dispatch_getattributes(request->dispatch);
1471         socket = NULL;
1472         if (DNS_REQUEST_CONNECTING(request) || DNS_REQUEST_SENDING(request)) {
1473                 if ((dispattr & DNS_DISPATCHATTR_EXCLUSIVE) != 0) {
1474                         if (request->dispentry != NULL) {
1475                                 socket = dns_dispatch_getentrysocket(
1476                                         request->dispentry);
1477                         }
1478                 } else
1479                         socket = dns_dispatch_getsocket(request->dispatch);
1480                 if (DNS_REQUEST_CONNECTING(request) && socket != NULL)
1481                         isc_socket_cancel(socket, NULL, ISC_SOCKCANCEL_CONNECT);
1482                 if (DNS_REQUEST_SENDING(request) && socket != NULL)
1483                         isc_socket_cancel(socket, NULL, ISC_SOCKCANCEL_SEND);
1484         }
1485         if (request->dispentry != NULL)
1486                 dns_dispatch_removeresponse(&request->dispentry, NULL);
1487         dns_dispatch_detach(&request->dispatch);
1488 }
1489
1490 static void
1491 req_log(int level, const char *fmt, ...) {
1492         va_list ap;
1493
1494         va_start(ap, fmt);
1495         isc_log_vwrite(dns_lctx, DNS_LOGCATEGORY_GENERAL,
1496                        DNS_LOGMODULE_REQUEST, level, fmt, ap);
1497         va_end(ap);
1498 }