dispatch.c revision 254402
193787Sdes/* 294691Sdes * Copyright (C) 2004-2009, 2011-2013 Internet Systems Consortium, Inc. ("ISC") 393787Sdes * Copyright (C) 1999-2003 Internet Software Consortium. 493787Sdes * 593787Sdes * Permission to use, copy, modify, and/or distribute this software for any 693787Sdes * purpose with or without fee is hereby granted, provided that the above 793787Sdes * copyright notice and this permission notice appear in all copies. 893787Sdes * 993787Sdes * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH 1093787Sdes * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 1193787Sdes * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, 1293787Sdes * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 1393787Sdes * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE 1493787Sdes * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 1593787Sdes * PERFORMANCE OF THIS SOFTWARE. 1693787Sdes */ 1793787Sdes 1893787Sdes/* $Id$ */ 1993787Sdes 2093787Sdes/*! \file */ 2193787Sdes 2293787Sdes#include <config.h> 2393787Sdes 2493787Sdes#include <stdlib.h> 2593787Sdes#include <sys/types.h> 2693787Sdes#include <unistd.h> 2793787Sdes#include <stdlib.h> 2893787Sdes 2993787Sdes#include <isc/entropy.h> 3093787Sdes#include <isc/mem.h> 3193787Sdes#include <isc/mutex.h> 3293787Sdes#include <isc/portset.h> 3393787Sdes#include <isc/print.h> 3493787Sdes#include <isc/random.h> 3593787Sdes#include <isc/stats.h> 3693787Sdes#include <isc/string.h> 3793787Sdes#include <isc/task.h> 3893787Sdes#include <isc/time.h> 3993787Sdes#include <isc/util.h> 4094691Sdes 4194691Sdes#include <dns/acl.h> 4293787Sdes#include <dns/dispatch.h> 4393787Sdes#include <dns/events.h> 4493787Sdes#include <dns/log.h> 4593787Sdes#include <dns/message.h> 4693787Sdes#include <dns/portlist.h> 4793787Sdes#include <dns/stats.h> 4893787Sdes#include <dns/tcpmsg.h> 4993787Sdes#include <dns/types.h> 5093787Sdes 5193787Sdestypedef ISC_LIST(dns_dispentry_t) dns_displist_t; 5293787Sdes 5394691Sdestypedef struct dispsocket dispsocket_t; 5494691Sdestypedef ISC_LIST(dispsocket_t) dispsocketlist_t; 5593787Sdes 5693787Sdestypedef struct dispportentry dispportentry_t; 5793787Sdestypedef ISC_LIST(dispportentry_t) dispportlist_t; 5893787Sdes 5993787Sdes/* ARC4 Random generator state */ 6093787Sdestypedef struct arc4ctx { 6193787Sdes isc_uint8_t i; 6293787Sdes isc_uint8_t j; 6393787Sdes isc_uint8_t s[256]; 6493787Sdes int count; 6594691Sdes isc_entropy_t *entropy; /*%< entropy source for ARC4 */ 6694691Sdes isc_mutex_t *lock; 6793787Sdes} arc4ctx_t; 6893787Sdes 6993787Sdestypedef struct dns_qid { 7093787Sdes unsigned int magic; 7193787Sdes unsigned int qid_nbuckets; /*%< hash table size */ 7293787Sdes unsigned int qid_increment; /*%< id increment on collision */ 7393787Sdes isc_mutex_t lock; 7493787Sdes dns_displist_t *qid_table; /*%< the table itself */ 7593787Sdes dispsocketlist_t *sock_table; /*%< socket table */ 7693787Sdes} dns_qid_t; 7793787Sdes 7894691Sdesstruct dns_dispatchmgr { 7994691Sdes /* Unlocked. */ 8093787Sdes unsigned int magic; 8193787Sdes isc_mem_t *mctx; 8293787Sdes dns_acl_t *blackhole; 8393787Sdes dns_portlist_t *portlist; 8493787Sdes isc_stats_t *stats; 8593787Sdes isc_entropy_t *entropy; /*%< entropy source */ 8693787Sdes 8793787Sdes /* Locked by "lock". */ 8893787Sdes isc_mutex_t lock; 8993787Sdes unsigned int state; 9093787Sdes ISC_LIST(dns_dispatch_t) list; 9193787Sdes 9293787Sdes /* Locked by arc4_lock. */ 93 isc_mutex_t arc4_lock; 94 arc4ctx_t arc4ctx; /*%< ARC4 context for QID */ 95 96 /* locked by buffer lock */ 97 dns_qid_t *qid; 98 isc_mutex_t buffer_lock; 99 unsigned int buffers; /*%< allocated buffers */ 100 unsigned int buffersize; /*%< size of each buffer */ 101 unsigned int maxbuffers; /*%< max buffers */ 102 103 /* Locked internally. */ 104 isc_mutex_t pool_lock; 105 isc_mempool_t *epool; /*%< memory pool for events */ 106 isc_mempool_t *rpool; /*%< memory pool for replies */ 107 isc_mempool_t *dpool; /*%< dispatch allocations */ 108 isc_mempool_t *bpool; /*%< memory pool for buffers */ 109 isc_mempool_t *spool; /*%< memory pool for dispsocs */ 110 111 /*% 112 * Locked by qid->lock if qid exists; otherwise, can be used without 113 * being locked. 114 * Memory footprint considerations: this is a simple implementation of 115 * available ports, i.e., an ordered array of the actual port numbers. 116 * This will require about 256KB of memory in the worst case (128KB for 117 * each of IPv4 and IPv6). We could reduce it by representing it as a 118 * more sophisticated way such as a list (or array) of ranges that are 119 * searched to identify a specific port. Our decision here is the saved 120 * memory isn't worth the implementation complexity, considering the 121 * fact that the whole BIND9 process (which is mainly named) already 122 * requires a pretty large memory footprint. We may, however, have to 123 * revisit the decision when we want to use it as a separate module for 124 * an environment where memory requirement is severer. 125 */ 126 in_port_t *v4ports; /*%< available ports for IPv4 */ 127 unsigned int nv4ports; /*%< # of available ports for IPv4 */ 128 in_port_t *v6ports; /*%< available ports for IPv4 */ 129 unsigned int nv6ports; /*%< # of available ports for IPv4 */ 130}; 131 132#define MGR_SHUTTINGDOWN 0x00000001U 133#define MGR_IS_SHUTTINGDOWN(l) (((l)->state & MGR_SHUTTINGDOWN) != 0) 134 135#define IS_PRIVATE(d) (((d)->attributes & DNS_DISPATCHATTR_PRIVATE) != 0) 136 137struct dns_dispentry { 138 unsigned int magic; 139 dns_dispatch_t *disp; 140 dns_messageid_t id; 141 in_port_t port; 142 unsigned int bucket; 143 isc_sockaddr_t host; 144 isc_task_t *task; 145 isc_taskaction_t action; 146 void *arg; 147 isc_boolean_t item_out; 148 dispsocket_t *dispsocket; 149 ISC_LIST(dns_dispatchevent_t) items; 150 ISC_LINK(dns_dispentry_t) link; 151}; 152 153/*% 154 * Maximum number of dispatch sockets that can be pooled for reuse. The 155 * appropriate value may vary, but experiments have shown a busy caching server 156 * may need more than 1000 sockets concurrently opened. The maximum allowable 157 * number of dispatch sockets (per manager) will be set to the double of this 158 * value. 159 */ 160#ifndef DNS_DISPATCH_POOLSOCKS 161#define DNS_DISPATCH_POOLSOCKS 2048 162#endif 163 164/*% 165 * Quota to control the number of dispatch sockets. If a dispatch has more 166 * than the quota of sockets, new queries will purge oldest ones, so that 167 * a massive number of outstanding queries won't prevent subsequent queries 168 * (especially if the older ones take longer time and result in timeout). 169 */ 170#ifndef DNS_DISPATCH_SOCKSQUOTA 171#define DNS_DISPATCH_SOCKSQUOTA 3072 172#endif 173 174struct dispsocket { 175 unsigned int magic; 176 isc_socket_t *socket; 177 dns_dispatch_t *disp; 178 isc_sockaddr_t host; 179 in_port_t localport; /* XXX: should be removed later */ 180 dispportentry_t *portentry; 181 dns_dispentry_t *resp; 182 isc_task_t *task; 183 ISC_LINK(dispsocket_t) link; 184 unsigned int bucket; 185 ISC_LINK(dispsocket_t) blink; 186}; 187 188/*% 189 * A port table entry. We remember every port we first open in a table with a 190 * reference counter so that we can 'reuse' the same port (with different 191 * destination addresses) using the SO_REUSEADDR socket option. 192 */ 193struct dispportentry { 194 in_port_t port; 195 unsigned int refs; 196 ISC_LINK(struct dispportentry) link; 197}; 198 199#ifndef DNS_DISPATCH_PORTTABLESIZE 200#define DNS_DISPATCH_PORTTABLESIZE 1024 201#endif 202 203#define INVALID_BUCKET (0xffffdead) 204 205/*% 206 * Number of tasks for each dispatch that use separate sockets for different 207 * transactions. This must be a power of 2 as it will divide 32 bit numbers 208 * to get an uniformly random tasks selection. See get_dispsocket(). 209 */ 210#define MAX_INTERNAL_TASKS 64 211 212struct dns_dispatch { 213 /* Unlocked. */ 214 unsigned int magic; /*%< magic */ 215 dns_dispatchmgr_t *mgr; /*%< dispatch manager */ 216 int ntasks; 217 /*% 218 * internal task buckets. We use multiple tasks to distribute various 219 * socket events well when using separate dispatch sockets. We use the 220 * 1st task (task[0]) for internal control events. 221 */ 222 isc_task_t *task[MAX_INTERNAL_TASKS]; 223 isc_socket_t *socket; /*%< isc socket attached to */ 224 isc_sockaddr_t local; /*%< local address */ 225 in_port_t localport; /*%< local UDP port */ 226 unsigned int maxrequests; /*%< max requests */ 227 isc_event_t *ctlevent; 228 229 /*% Locked by mgr->lock. */ 230 ISC_LINK(dns_dispatch_t) link; 231 232 /* Locked by "lock". */ 233 isc_mutex_t lock; /*%< locks all below */ 234 isc_sockettype_t socktype; 235 unsigned int attributes; 236 unsigned int refcount; /*%< number of users */ 237 dns_dispatchevent_t *failsafe_ev; /*%< failsafe cancel event */ 238 unsigned int shutting_down : 1, 239 shutdown_out : 1, 240 connected : 1, 241 tcpmsg_valid : 1, 242 recv_pending : 1; /*%< is a recv() pending? */ 243 isc_result_t shutdown_why; 244 ISC_LIST(dispsocket_t) activesockets; 245 ISC_LIST(dispsocket_t) inactivesockets; 246 unsigned int nsockets; 247 unsigned int requests; /*%< how many requests we have */ 248 unsigned int tcpbuffers; /*%< allocated buffers */ 249 dns_tcpmsg_t tcpmsg; /*%< for tcp streams */ 250 dns_qid_t *qid; 251 arc4ctx_t arc4ctx; /*%< for QID/UDP port num */ 252 dispportlist_t *port_table; /*%< hold ports 'owned' by us */ 253 isc_mempool_t *portpool; /*%< port table entries */ 254}; 255 256#define QID_MAGIC ISC_MAGIC('Q', 'i', 'd', ' ') 257#define VALID_QID(e) ISC_MAGIC_VALID((e), QID_MAGIC) 258 259#define RESPONSE_MAGIC ISC_MAGIC('D', 'r', 's', 'p') 260#define VALID_RESPONSE(e) ISC_MAGIC_VALID((e), RESPONSE_MAGIC) 261 262#define DISPSOCK_MAGIC ISC_MAGIC('D', 's', 'o', 'c') 263#define VALID_DISPSOCK(e) ISC_MAGIC_VALID((e), DISPSOCK_MAGIC) 264 265#define DISPATCH_MAGIC ISC_MAGIC('D', 'i', 's', 'p') 266#define VALID_DISPATCH(e) ISC_MAGIC_VALID((e), DISPATCH_MAGIC) 267 268#define DNS_DISPATCHMGR_MAGIC ISC_MAGIC('D', 'M', 'g', 'r') 269#define VALID_DISPATCHMGR(e) ISC_MAGIC_VALID((e), DNS_DISPATCHMGR_MAGIC) 270 271#define DNS_QID(disp) ((disp)->socktype == isc_sockettype_tcp) ? \ 272 (disp)->qid : (disp)->mgr->qid 273#define DISP_ARC4CTX(disp) ((disp)->socktype == isc_sockettype_udp) ? \ 274 (&(disp)->arc4ctx) : (&(disp)->mgr->arc4ctx) 275 276/*% 277 * Locking a query port buffer is a bit tricky. We access the buffer without 278 * locking until qid is created. Technically, there is a possibility of race 279 * between the creation of qid and access to the port buffer; in practice, 280 * however, this should be safe because qid isn't created until the first 281 * dispatch is created and there should be no contending situation until then. 282 */ 283#define PORTBUFLOCK(mgr) if ((mgr)->qid != NULL) LOCK(&((mgr)->qid->lock)) 284#define PORTBUFUNLOCK(mgr) if ((mgr)->qid != NULL) UNLOCK((&(mgr)->qid->lock)) 285 286/* 287 * Statics. 288 */ 289static dns_dispentry_t *entry_search(dns_qid_t *, isc_sockaddr_t *, 290 dns_messageid_t, in_port_t, unsigned int); 291static isc_boolean_t destroy_disp_ok(dns_dispatch_t *); 292static void destroy_disp(isc_task_t *task, isc_event_t *event); 293static void destroy_dispsocket(dns_dispatch_t *, dispsocket_t **); 294static void deactivate_dispsocket(dns_dispatch_t *, dispsocket_t *); 295static void udp_exrecv(isc_task_t *, isc_event_t *); 296static void udp_shrecv(isc_task_t *, isc_event_t *); 297static void udp_recv(isc_event_t *, dns_dispatch_t *, dispsocket_t *); 298static void tcp_recv(isc_task_t *, isc_event_t *); 299static isc_result_t startrecv(dns_dispatch_t *, dispsocket_t *); 300static isc_uint32_t dns_hash(dns_qid_t *, isc_sockaddr_t *, dns_messageid_t, 301 in_port_t); 302static void free_buffer(dns_dispatch_t *disp, void *buf, unsigned int len); 303static void *allocate_udp_buffer(dns_dispatch_t *disp); 304static inline void free_event(dns_dispatch_t *disp, dns_dispatchevent_t *ev); 305static inline dns_dispatchevent_t *allocate_event(dns_dispatch_t *disp); 306static void do_cancel(dns_dispatch_t *disp); 307static dns_dispentry_t *linear_first(dns_qid_t *disp); 308static dns_dispentry_t *linear_next(dns_qid_t *disp, 309 dns_dispentry_t *resp); 310static void dispatch_free(dns_dispatch_t **dispp); 311static isc_result_t get_udpsocket(dns_dispatchmgr_t *mgr, 312 dns_dispatch_t *disp, 313 isc_socketmgr_t *sockmgr, 314 isc_sockaddr_t *localaddr, 315 isc_socket_t **sockp); 316static isc_result_t dispatch_createudp(dns_dispatchmgr_t *mgr, 317 isc_socketmgr_t *sockmgr, 318 isc_taskmgr_t *taskmgr, 319 isc_sockaddr_t *localaddr, 320 unsigned int maxrequests, 321 unsigned int attributes, 322 dns_dispatch_t **dispp); 323static isc_boolean_t destroy_mgr_ok(dns_dispatchmgr_t *mgr); 324static void destroy_mgr(dns_dispatchmgr_t **mgrp); 325static isc_result_t qid_allocate(dns_dispatchmgr_t *mgr, unsigned int buckets, 326 unsigned int increment, dns_qid_t **qidp, 327 isc_boolean_t needaddrtable); 328static void qid_destroy(isc_mem_t *mctx, dns_qid_t **qidp); 329static isc_result_t open_socket(isc_socketmgr_t *mgr, isc_sockaddr_t *local, 330 unsigned int options, isc_socket_t **sockp); 331static isc_boolean_t portavailable(dns_dispatchmgr_t *mgr, isc_socket_t *sock, 332 isc_sockaddr_t *sockaddrp); 333 334#define LVL(x) ISC_LOG_DEBUG(x) 335 336static void 337mgr_log(dns_dispatchmgr_t *mgr, int level, const char *fmt, ...) 338 ISC_FORMAT_PRINTF(3, 4); 339 340static void 341mgr_log(dns_dispatchmgr_t *mgr, int level, const char *fmt, ...) { 342 char msgbuf[2048]; 343 va_list ap; 344 345 if (! isc_log_wouldlog(dns_lctx, level)) 346 return; 347 348 va_start(ap, fmt); 349 vsnprintf(msgbuf, sizeof(msgbuf), fmt, ap); 350 va_end(ap); 351 352 isc_log_write(dns_lctx, 353 DNS_LOGCATEGORY_DISPATCH, DNS_LOGMODULE_DISPATCH, 354 level, "dispatchmgr %p: %s", mgr, msgbuf); 355} 356 357static inline void 358inc_stats(dns_dispatchmgr_t *mgr, isc_statscounter_t counter) { 359 if (mgr->stats != NULL) 360 isc_stats_increment(mgr->stats, counter); 361} 362 363static void 364dispatch_log(dns_dispatch_t *disp, int level, const char *fmt, ...) 365 ISC_FORMAT_PRINTF(3, 4); 366 367static void 368dispatch_log(dns_dispatch_t *disp, int level, const char *fmt, ...) { 369 char msgbuf[2048]; 370 va_list ap; 371 372 if (! isc_log_wouldlog(dns_lctx, level)) 373 return; 374 375 va_start(ap, fmt); 376 vsnprintf(msgbuf, sizeof(msgbuf), fmt, ap); 377 va_end(ap); 378 379 isc_log_write(dns_lctx, 380 DNS_LOGCATEGORY_DISPATCH, DNS_LOGMODULE_DISPATCH, 381 level, "dispatch %p: %s", disp, msgbuf); 382} 383 384static void 385request_log(dns_dispatch_t *disp, dns_dispentry_t *resp, 386 int level, const char *fmt, ...) 387 ISC_FORMAT_PRINTF(4, 5); 388 389static void 390request_log(dns_dispatch_t *disp, dns_dispentry_t *resp, 391 int level, const char *fmt, ...) 392{ 393 char msgbuf[2048]; 394 char peerbuf[256]; 395 va_list ap; 396 397 if (! isc_log_wouldlog(dns_lctx, level)) 398 return; 399 400 va_start(ap, fmt); 401 vsnprintf(msgbuf, sizeof(msgbuf), fmt, ap); 402 va_end(ap); 403 404 if (VALID_RESPONSE(resp)) { 405 isc_sockaddr_format(&resp->host, peerbuf, sizeof(peerbuf)); 406 isc_log_write(dns_lctx, DNS_LOGCATEGORY_DISPATCH, 407 DNS_LOGMODULE_DISPATCH, level, 408 "dispatch %p response %p %s: %s", disp, resp, 409 peerbuf, msgbuf); 410 } else { 411 isc_log_write(dns_lctx, DNS_LOGCATEGORY_DISPATCH, 412 DNS_LOGMODULE_DISPATCH, level, 413 "dispatch %p req/resp %p: %s", disp, resp, 414 msgbuf); 415 } 416} 417 418/*% 419 * ARC4 random number generator derived from OpenBSD. 420 * Only dispatch_random() and dispatch_uniformrandom() are expected 421 * to be called from general dispatch routines; the rest of them are subroutines 422 * for these two. 423 * 424 * The original copyright follows: 425 * Copyright (c) 1996, David Mazieres <dm@uun.org> 426 * Copyright (c) 2008, Damien Miller <djm@openbsd.org> 427 * 428 * Permission to use, copy, modify, and distribute this software for any 429 * purpose with or without fee is hereby granted, provided that the above 430 * copyright notice and this permission notice appear in all copies. 431 * 432 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 433 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 434 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 435 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 436 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 437 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 438 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 439 */ 440#ifdef BIND9 441static void 442dispatch_initrandom(arc4ctx_t *actx, isc_entropy_t *entropy, 443 isc_mutex_t *lock) 444{ 445 int n; 446 for (n = 0; n < 256; n++) 447 actx->s[n] = n; 448 actx->i = 0; 449 actx->j = 0; 450 actx->count = 0; 451 actx->entropy = entropy; /* don't have to attach */ 452 actx->lock = lock; 453} 454 455static void 456dispatch_arc4addrandom(arc4ctx_t *actx, unsigned char *dat, int datlen) { 457 int n; 458 isc_uint8_t si; 459 460 actx->i--; 461 for (n = 0; n < 256; n++) { 462 actx->i = (actx->i + 1); 463 si = actx->s[actx->i]; 464 actx->j = (actx->j + si + dat[n % datlen]); 465 actx->s[actx->i] = actx->s[actx->j]; 466 actx->s[actx->j] = si; 467 } 468 actx->j = actx->i; 469} 470 471static inline isc_uint8_t 472dispatch_arc4get8(arc4ctx_t *actx) { 473 isc_uint8_t si, sj; 474 475 actx->i = (actx->i + 1); 476 si = actx->s[actx->i]; 477 actx->j = (actx->j + si); 478 sj = actx->s[actx->j]; 479 actx->s[actx->i] = sj; 480 actx->s[actx->j] = si; 481 482 return (actx->s[(si + sj) & 0xff]); 483} 484 485static inline isc_uint16_t 486dispatch_arc4get16(arc4ctx_t *actx) { 487 isc_uint16_t val; 488 489 val = dispatch_arc4get8(actx) << 8; 490 val |= dispatch_arc4get8(actx); 491 492 return (val); 493} 494 495static void 496dispatch_arc4stir(arc4ctx_t *actx) { 497 int i; 498 union { 499 unsigned char rnd[128]; 500 isc_uint32_t rnd32[32]; 501 } rnd; 502 isc_result_t result; 503 504 if (actx->entropy != NULL) { 505 /* 506 * We accept any quality of random data to avoid blocking. 507 */ 508 result = isc_entropy_getdata(actx->entropy, rnd.rnd, 509 sizeof(rnd), NULL, 0); 510 RUNTIME_CHECK(result == ISC_R_SUCCESS); 511 } else { 512 for (i = 0; i < 32; i++) 513 isc_random_get(&rnd.rnd32[i]); 514 } 515 dispatch_arc4addrandom(actx, rnd.rnd, sizeof(rnd.rnd)); 516 517 /* 518 * Discard early keystream, as per recommendations in: 519 * http://www.wisdom.weizmann.ac.il/~itsik/RC4/Papers/Rc4_ksa.ps 520 */ 521 for (i = 0; i < 256; i++) 522 (void)dispatch_arc4get8(actx); 523 524 /* 525 * Derived from OpenBSD's implementation. The rationale is not clear, 526 * but should be conservative enough in safety, and reasonably large 527 * for efficiency. 528 */ 529 actx->count = 1600000; 530} 531 532static isc_uint16_t 533dispatch_random(arc4ctx_t *actx) { 534 isc_uint16_t result; 535 536 if (actx->lock != NULL) 537 LOCK(actx->lock); 538 539 actx->count -= sizeof(isc_uint16_t); 540 if (actx->count <= 0) 541 dispatch_arc4stir(actx); 542 result = dispatch_arc4get16(actx); 543 544 if (actx->lock != NULL) 545 UNLOCK(actx->lock); 546 547 return (result); 548} 549#else 550/* 551 * For general purpose library, we don't have to be too strict about the 552 * quality of random values. Performance doesn't matter much, either. 553 * So we simply use the isc_random module to keep the library as small as 554 * possible. 555 */ 556 557static void 558dispatch_initrandom(arc4ctx_t *actx, isc_entropy_t *entropy, 559 isc_mutex_t *lock) 560{ 561 UNUSED(actx); 562 UNUSED(entropy); 563 UNUSED(lock); 564 565 return; 566} 567 568static isc_uint16_t 569dispatch_random(arc4ctx_t *actx) { 570 isc_uint32_t r; 571 572 UNUSED(actx); 573 574 isc_random_get(&r); 575 return (r & 0xffff); 576} 577#endif /* BIND9 */ 578 579static isc_uint16_t 580dispatch_uniformrandom(arc4ctx_t *actx, isc_uint16_t upper_bound) { 581 isc_uint16_t min, r; 582 583 if (upper_bound < 2) 584 return (0); 585 586 /* 587 * Ensure the range of random numbers [min, 0xffff] be a multiple of 588 * upper_bound and contain at least a half of the 16 bit range. 589 */ 590 591 if (upper_bound > 0x8000) 592 min = 1 + ~upper_bound; /* 0x8000 - upper_bound */ 593 else 594 min = (isc_uint16_t)(0x10000 % (isc_uint32_t)upper_bound); 595 596 /* 597 * This could theoretically loop forever but each retry has 598 * p > 0.5 (worst case, usually far better) of selecting a 599 * number inside the range we need, so it should rarely need 600 * to re-roll. 601 */ 602 for (;;) { 603 r = dispatch_random(actx); 604 if (r >= min) 605 break; 606 } 607 608 return (r % upper_bound); 609} 610 611/* 612 * Return a hash of the destination and message id. 613 */ 614static isc_uint32_t 615dns_hash(dns_qid_t *qid, isc_sockaddr_t *dest, dns_messageid_t id, 616 in_port_t port) 617{ 618 unsigned int ret; 619 620 ret = isc_sockaddr_hash(dest, ISC_TRUE); 621 ret ^= (id << 16) | port; 622 ret %= qid->qid_nbuckets; 623 624 INSIST(ret < qid->qid_nbuckets); 625 626 return (ret); 627} 628 629/* 630 * Find the first entry in 'qid'. Returns NULL if there are no entries. 631 */ 632static dns_dispentry_t * 633linear_first(dns_qid_t *qid) { 634 dns_dispentry_t *ret; 635 unsigned int bucket; 636 637 bucket = 0; 638 639 while (bucket < qid->qid_nbuckets) { 640 ret = ISC_LIST_HEAD(qid->qid_table[bucket]); 641 if (ret != NULL) 642 return (ret); 643 bucket++; 644 } 645 646 return (NULL); 647} 648 649/* 650 * Find the next entry after 'resp' in 'qid'. Return NULL if there are 651 * no more entries. 652 */ 653static dns_dispentry_t * 654linear_next(dns_qid_t *qid, dns_dispentry_t *resp) { 655 dns_dispentry_t *ret; 656 unsigned int bucket; 657 658 ret = ISC_LIST_NEXT(resp, link); 659 if (ret != NULL) 660 return (ret); 661 662 bucket = resp->bucket; 663 bucket++; 664 while (bucket < qid->qid_nbuckets) { 665 ret = ISC_LIST_HEAD(qid->qid_table[bucket]); 666 if (ret != NULL) 667 return (ret); 668 bucket++; 669 } 670 671 return (NULL); 672} 673 674/* 675 * The dispatch must be locked. 676 */ 677static isc_boolean_t 678destroy_disp_ok(dns_dispatch_t *disp) 679{ 680 if (disp->refcount != 0) 681 return (ISC_FALSE); 682 683 if (disp->recv_pending != 0) 684 return (ISC_FALSE); 685 686 if (!ISC_LIST_EMPTY(disp->activesockets)) 687 return (ISC_FALSE); 688 689 if (disp->shutting_down == 0) 690 return (ISC_FALSE); 691 692 return (ISC_TRUE); 693} 694 695/* 696 * Called when refcount reaches 0 (and safe to destroy). 697 * 698 * The dispatcher must not be locked. 699 * The manager must be locked. 700 */ 701static void 702destroy_disp(isc_task_t *task, isc_event_t *event) { 703 dns_dispatch_t *disp; 704 dns_dispatchmgr_t *mgr; 705 isc_boolean_t killmgr; 706 dispsocket_t *dispsocket; 707 int i; 708 709 INSIST(event->ev_type == DNS_EVENT_DISPATCHCONTROL); 710 711 UNUSED(task); 712 713 disp = event->ev_arg; 714 mgr = disp->mgr; 715 716 LOCK(&mgr->lock); 717 ISC_LIST_UNLINK(mgr->list, disp, link); 718 719 dispatch_log(disp, LVL(90), 720 "shutting down; detaching from sock %p, task %p", 721 disp->socket, disp->task[0]); /* XXXX */ 722 723 if (disp->socket != NULL) 724 isc_socket_detach(&disp->socket); 725 while ((dispsocket = ISC_LIST_HEAD(disp->inactivesockets)) != NULL) { 726 ISC_LIST_UNLINK(disp->inactivesockets, dispsocket, link); 727 destroy_dispsocket(disp, &dispsocket); 728 } 729 for (i = 0; i < disp->ntasks; i++) 730 isc_task_detach(&disp->task[i]); 731 isc_event_free(&event); 732 733 dispatch_free(&disp); 734 735 killmgr = destroy_mgr_ok(mgr); 736 UNLOCK(&mgr->lock); 737 if (killmgr) 738 destroy_mgr(&mgr); 739} 740 741/*% 742 * Manipulate port table per dispatch: find an entry for a given port number, 743 * create a new entry, and decrement a given entry with possible clean-up. 744 */ 745static dispportentry_t * 746port_search(dns_dispatch_t *disp, in_port_t port) { 747 dispportentry_t *portentry; 748 749 REQUIRE(disp->port_table != NULL); 750 751 portentry = ISC_LIST_HEAD(disp->port_table[port % 752 DNS_DISPATCH_PORTTABLESIZE]); 753 while (portentry != NULL) { 754 if (portentry->port == port) 755 return (portentry); 756 portentry = ISC_LIST_NEXT(portentry, link); 757 } 758 759 return (NULL); 760} 761 762static dispportentry_t * 763new_portentry(dns_dispatch_t *disp, in_port_t port) { 764 dispportentry_t *portentry; 765 766 REQUIRE(disp->port_table != NULL); 767 768 portentry = isc_mempool_get(disp->portpool); 769 if (portentry == NULL) 770 return (portentry); 771 772 portentry->port = port; 773 portentry->refs = 0; 774 ISC_LINK_INIT(portentry, link); 775 ISC_LIST_APPEND(disp->port_table[port % DNS_DISPATCH_PORTTABLESIZE], 776 portentry, link); 777 778 return (portentry); 779} 780 781/*% 782 * The caller must not hold the qid->lock. 783 */ 784static void 785deref_portentry(dns_dispatch_t *disp, dispportentry_t **portentryp) { 786 dispportentry_t *portentry = *portentryp; 787 dns_qid_t *qid; 788 789 REQUIRE(disp->port_table != NULL); 790 REQUIRE(portentry != NULL && portentry->refs > 0); 791 792 qid = DNS_QID(disp); 793 LOCK(&qid->lock); 794 portentry->refs--; 795 if (portentry->refs == 0) { 796 ISC_LIST_UNLINK(disp->port_table[portentry->port % 797 DNS_DISPATCH_PORTTABLESIZE], 798 portentry, link); 799 isc_mempool_put(disp->portpool, portentry); 800 } 801 802 *portentryp = NULL; 803 UNLOCK(&qid->lock); 804} 805 806/*% 807 * Find a dispsocket for socket address 'dest', and port number 'port'. 808 * Return NULL if no such entry exists. 809 */ 810static dispsocket_t * 811socket_search(dns_qid_t *qid, isc_sockaddr_t *dest, in_port_t port, 812 unsigned int bucket) 813{ 814 dispsocket_t *dispsock; 815 816 REQUIRE(bucket < qid->qid_nbuckets); 817 818 dispsock = ISC_LIST_HEAD(qid->sock_table[bucket]); 819 820 while (dispsock != NULL) { 821 if (dispsock->portentry != NULL && 822 dispsock->portentry->port == port && 823 isc_sockaddr_equal(dest, &dispsock->host)) 824 return (dispsock); 825 dispsock = ISC_LIST_NEXT(dispsock, blink); 826 } 827 828 return (NULL); 829} 830 831/*% 832 * Make a new socket for a single dispatch with a random port number. 833 * The caller must hold the disp->lock and qid->lock. 834 */ 835static isc_result_t 836get_dispsocket(dns_dispatch_t *disp, isc_sockaddr_t *dest, 837 isc_socketmgr_t *sockmgr, dns_qid_t *qid, 838 dispsocket_t **dispsockp, in_port_t *portp) 839{ 840 int i; 841 isc_uint32_t r; 842 dns_dispatchmgr_t *mgr = disp->mgr; 843 isc_socket_t *sock = NULL; 844 isc_result_t result = ISC_R_FAILURE; 845 in_port_t port; 846 isc_sockaddr_t localaddr; 847 unsigned int bucket = 0; 848 dispsocket_t *dispsock; 849 unsigned int nports; 850 in_port_t *ports; 851 unsigned int bindoptions; 852 dispportentry_t *portentry = NULL; 853 854 if (isc_sockaddr_pf(&disp->local) == AF_INET) { 855 nports = disp->mgr->nv4ports; 856 ports = disp->mgr->v4ports; 857 } else { 858 nports = disp->mgr->nv6ports; 859 ports = disp->mgr->v6ports; 860 } 861 if (nports == 0) 862 return (ISC_R_ADDRNOTAVAIL); 863 864 dispsock = ISC_LIST_HEAD(disp->inactivesockets); 865 if (dispsock != NULL) { 866 ISC_LIST_UNLINK(disp->inactivesockets, dispsock, link); 867 sock = dispsock->socket; 868 dispsock->socket = NULL; 869 } else { 870 dispsock = isc_mempool_get(mgr->spool); 871 if (dispsock == NULL) 872 return (ISC_R_NOMEMORY); 873 874 disp->nsockets++; 875 dispsock->socket = NULL; 876 dispsock->disp = disp; 877 dispsock->resp = NULL; 878 dispsock->portentry = NULL; 879 isc_random_get(&r); 880 dispsock->task = NULL; 881 isc_task_attach(disp->task[r % disp->ntasks], &dispsock->task); 882 ISC_LINK_INIT(dispsock, link); 883 ISC_LINK_INIT(dispsock, blink); 884 dispsock->magic = DISPSOCK_MAGIC; 885 } 886 887 /* 888 * Pick up a random UDP port and open a new socket with it. Avoid 889 * choosing ports that share the same destination because it will be 890 * very likely to fail in bind(2) or connect(2). 891 */ 892 localaddr = disp->local; 893 for (i = 0; i < 64; i++) { 894 port = ports[dispatch_uniformrandom(DISP_ARC4CTX(disp), 895 nports)]; 896 isc_sockaddr_setport(&localaddr, port); 897 898 bucket = dns_hash(qid, dest, 0, port); 899 if (socket_search(qid, dest, port, bucket) != NULL) 900 continue; 901 bindoptions = 0; 902 portentry = port_search(disp, port); 903 if (portentry != NULL) 904 bindoptions |= ISC_SOCKET_REUSEADDRESS; 905 result = open_socket(sockmgr, &localaddr, bindoptions, &sock); 906 if (result == ISC_R_SUCCESS) { 907 if (portentry == NULL) { 908 portentry = new_portentry(disp, port); 909 if (portentry == NULL) { 910 result = ISC_R_NOMEMORY; 911 break; 912 } 913 } 914 portentry->refs++; 915 break; 916 } else if (result == ISC_R_NOPERM) { 917 char buf[ISC_SOCKADDR_FORMATSIZE]; 918 isc_sockaddr_format(&localaddr, buf, sizeof(buf)); 919 dispatch_log(disp, ISC_LOG_WARNING, 920 "open_socket(%s) -> %s: continuing", 921 buf, isc_result_totext(result)); 922 } else if (result != ISC_R_ADDRINUSE) 923 break; 924 } 925 926 if (result == ISC_R_SUCCESS) { 927 dispsock->socket = sock; 928 dispsock->host = *dest; 929 dispsock->portentry = portentry; 930 dispsock->bucket = bucket; 931 ISC_LIST_APPEND(qid->sock_table[bucket], dispsock, blink); 932 *dispsockp = dispsock; 933 *portp = port; 934 } else { 935 /* 936 * We could keep it in the inactive list, but since this should 937 * be an exceptional case and might be resource shortage, we'd 938 * rather destroy it. 939 */ 940 if (sock != NULL) 941 isc_socket_detach(&sock); 942 destroy_dispsocket(disp, &dispsock); 943 } 944 945 return (result); 946} 947 948/*% 949 * Destroy a dedicated dispatch socket. 950 */ 951static void 952destroy_dispsocket(dns_dispatch_t *disp, dispsocket_t **dispsockp) { 953 dispsocket_t *dispsock; 954 dns_qid_t *qid; 955 956 /* 957 * The dispatch must be locked. 958 */ 959 960 REQUIRE(dispsockp != NULL && *dispsockp != NULL); 961 dispsock = *dispsockp; 962 REQUIRE(!ISC_LINK_LINKED(dispsock, link)); 963 964 disp->nsockets--; 965 dispsock->magic = 0; 966 if (dispsock->portentry != NULL) 967 deref_portentry(disp, &dispsock->portentry); 968 if (dispsock->socket != NULL) 969 isc_socket_detach(&dispsock->socket); 970 if (ISC_LINK_LINKED(dispsock, blink)) { 971 qid = DNS_QID(disp); 972 LOCK(&qid->lock); 973 ISC_LIST_UNLINK(qid->sock_table[dispsock->bucket], dispsock, 974 blink); 975 UNLOCK(&qid->lock); 976 } 977 if (dispsock->task != NULL) 978 isc_task_detach(&dispsock->task); 979 isc_mempool_put(disp->mgr->spool, dispsock); 980 981 *dispsockp = NULL; 982} 983 984/*% 985 * Deactivate a dedicated dispatch socket. Move it to the inactive list for 986 * future reuse unless the total number of sockets are exceeding the maximum. 987 */ 988static void 989deactivate_dispsocket(dns_dispatch_t *disp, dispsocket_t *dispsock) { 990 isc_result_t result; 991 dns_qid_t *qid; 992 993 /* 994 * The dispatch must be locked. 995 */ 996 ISC_LIST_UNLINK(disp->activesockets, dispsock, link); 997 if (dispsock->resp != NULL) { 998 INSIST(dispsock->resp->dispsocket == dispsock); 999 dispsock->resp->dispsocket = NULL; 1000 } 1001 1002 INSIST(dispsock->portentry != NULL); 1003 deref_portentry(disp, &dispsock->portentry); 1004 1005#ifdef BIND9 1006 if (disp->nsockets > DNS_DISPATCH_POOLSOCKS) 1007 destroy_dispsocket(disp, &dispsock); 1008 else { 1009 result = isc_socket_close(dispsock->socket); 1010 1011 qid = DNS_QID(disp); 1012 LOCK(&qid->lock); 1013 ISC_LIST_UNLINK(qid->sock_table[dispsock->bucket], dispsock, 1014 blink); 1015 UNLOCK(&qid->lock); 1016 1017 if (result == ISC_R_SUCCESS) 1018 ISC_LIST_APPEND(disp->inactivesockets, dispsock, link); 1019 else { 1020 /* 1021 * If the underlying system does not allow this 1022 * optimization, destroy this temporary structure (and 1023 * create a new one for a new transaction). 1024 */ 1025 INSIST(result == ISC_R_NOTIMPLEMENTED); 1026 destroy_dispsocket(disp, &dispsock); 1027 } 1028 } 1029#else 1030 /* This kind of optimization isn't necessary for normal use */ 1031 UNUSED(qid); 1032 UNUSED(result); 1033 1034 destroy_dispsocket(disp, &dispsock); 1035#endif 1036} 1037 1038/* 1039 * Find an entry for query ID 'id', socket address 'dest', and port number 1040 * 'port'. 1041 * Return NULL if no such entry exists. 1042 */ 1043static dns_dispentry_t * 1044entry_search(dns_qid_t *qid, isc_sockaddr_t *dest, dns_messageid_t id, 1045 in_port_t port, unsigned int bucket) 1046{ 1047 dns_dispentry_t *res; 1048 1049 REQUIRE(bucket < qid->qid_nbuckets); 1050 1051 res = ISC_LIST_HEAD(qid->qid_table[bucket]); 1052 1053 while (res != NULL) { 1054 if (res->id == id && isc_sockaddr_equal(dest, &res->host) && 1055 res->port == port) { 1056 return (res); 1057 } 1058 res = ISC_LIST_NEXT(res, link); 1059 } 1060 1061 return (NULL); 1062} 1063 1064static void 1065free_buffer(dns_dispatch_t *disp, void *buf, unsigned int len) { 1066 INSIST(buf != NULL && len != 0); 1067 1068 1069 switch (disp->socktype) { 1070 case isc_sockettype_tcp: 1071 INSIST(disp->tcpbuffers > 0); 1072 disp->tcpbuffers--; 1073 isc_mem_put(disp->mgr->mctx, buf, len); 1074 break; 1075 case isc_sockettype_udp: 1076 LOCK(&disp->mgr->buffer_lock); 1077 INSIST(disp->mgr->buffers > 0); 1078 INSIST(len == disp->mgr->buffersize); 1079 disp->mgr->buffers--; 1080 isc_mempool_put(disp->mgr->bpool, buf); 1081 UNLOCK(&disp->mgr->buffer_lock); 1082 break; 1083 default: 1084 INSIST(0); 1085 break; 1086 } 1087} 1088 1089static void * 1090allocate_udp_buffer(dns_dispatch_t *disp) { 1091 void *temp; 1092 1093 LOCK(&disp->mgr->buffer_lock); 1094 temp = isc_mempool_get(disp->mgr->bpool); 1095 1096 if (temp != NULL) 1097 disp->mgr->buffers++; 1098 UNLOCK(&disp->mgr->buffer_lock); 1099 1100 return (temp); 1101} 1102 1103static inline void 1104free_event(dns_dispatch_t *disp, dns_dispatchevent_t *ev) { 1105 if (disp->failsafe_ev == ev) { 1106 INSIST(disp->shutdown_out == 1); 1107 disp->shutdown_out = 0; 1108 1109 return; 1110 } 1111 1112 isc_mempool_put(disp->mgr->epool, ev); 1113} 1114 1115static inline dns_dispatchevent_t * 1116allocate_event(dns_dispatch_t *disp) { 1117 dns_dispatchevent_t *ev; 1118 1119 ev = isc_mempool_get(disp->mgr->epool); 1120 if (ev == NULL) 1121 return (NULL); 1122 ISC_EVENT_INIT(ev, sizeof(*ev), 0, NULL, 0, 1123 NULL, NULL, NULL, NULL, NULL); 1124 1125 return (ev); 1126} 1127 1128static void 1129udp_exrecv(isc_task_t *task, isc_event_t *ev) { 1130 dispsocket_t *dispsock = ev->ev_arg; 1131 1132 UNUSED(task); 1133 1134 REQUIRE(VALID_DISPSOCK(dispsock)); 1135 udp_recv(ev, dispsock->disp, dispsock); 1136} 1137 1138static void 1139udp_shrecv(isc_task_t *task, isc_event_t *ev) { 1140 dns_dispatch_t *disp = ev->ev_arg; 1141 1142 UNUSED(task); 1143 1144 REQUIRE(VALID_DISPATCH(disp)); 1145 udp_recv(ev, disp, NULL); 1146} 1147 1148/* 1149 * General flow: 1150 * 1151 * If I/O result == CANCELED or error, free the buffer. 1152 * 1153 * If query, free the buffer, restart. 1154 * 1155 * If response: 1156 * Allocate event, fill in details. 1157 * If cannot allocate, free buffer, restart. 1158 * find target. If not found, free buffer, restart. 1159 * if event queue is not empty, queue. else, send. 1160 * restart. 1161 */ 1162static void 1163udp_recv(isc_event_t *ev_in, dns_dispatch_t *disp, dispsocket_t *dispsock) { 1164 isc_socketevent_t *ev = (isc_socketevent_t *)ev_in; 1165 dns_messageid_t id; 1166 isc_result_t dres; 1167 isc_buffer_t source; 1168 unsigned int flags; 1169 dns_dispentry_t *resp = NULL; 1170 dns_dispatchevent_t *rev; 1171 unsigned int bucket; 1172 isc_boolean_t killit; 1173 isc_boolean_t queue_response; 1174 dns_dispatchmgr_t *mgr; 1175 dns_qid_t *qid; 1176 isc_netaddr_t netaddr; 1177 int match; 1178 int result; 1179 isc_boolean_t qidlocked = ISC_FALSE; 1180 1181 LOCK(&disp->lock); 1182 1183 mgr = disp->mgr; 1184 qid = mgr->qid; 1185 1186 dispatch_log(disp, LVL(90), 1187 "got packet: requests %d, buffers %d, recvs %d", 1188 disp->requests, disp->mgr->buffers, disp->recv_pending); 1189 1190 if (dispsock == NULL && ev->ev_type == ISC_SOCKEVENT_RECVDONE) { 1191 /* 1192 * Unless the receive event was imported from a listening 1193 * interface, in which case the event type is 1194 * DNS_EVENT_IMPORTRECVDONE, receive operation must be pending. 1195 */ 1196 INSIST(disp->recv_pending != 0); 1197 disp->recv_pending = 0; 1198 } 1199 1200 if (dispsock != NULL && 1201 (ev->result == ISC_R_CANCELED || dispsock->resp == NULL)) { 1202 /* 1203 * dispsock->resp can be NULL if this transaction was canceled 1204 * just after receiving a response. Since this socket is 1205 * exclusively used and there should be at most one receive 1206 * event the canceled event should have been no effect. So 1207 * we can (and should) deactivate the socket right now. 1208 */ 1209 deactivate_dispsocket(disp, dispsock); 1210 dispsock = NULL; 1211 } 1212 1213 if (disp->shutting_down) { 1214 /* 1215 * This dispatcher is shutting down. 1216 */ 1217 free_buffer(disp, ev->region.base, ev->region.length); 1218 1219 isc_event_free(&ev_in); 1220 ev = NULL; 1221 1222 killit = destroy_disp_ok(disp); 1223 UNLOCK(&disp->lock); 1224 if (killit) 1225 isc_task_send(disp->task[0], &disp->ctlevent); 1226 1227 return; 1228 } 1229 1230 if ((disp->attributes & DNS_DISPATCHATTR_EXCLUSIVE) != 0) { 1231 if (dispsock != NULL) { 1232 resp = dispsock->resp; 1233 id = resp->id; 1234 if (ev->result != ISC_R_SUCCESS) { 1235 /* 1236 * This is most likely a network error on a 1237 * connected socket. It makes no sense to 1238 * check the address or parse the packet, but it 1239 * will help to return the error to the caller. 1240 */ 1241 goto sendresponse; 1242 } 1243 } else { 1244 free_buffer(disp, ev->region.base, ev->region.length); 1245 1246 UNLOCK(&disp->lock); 1247 isc_event_free(&ev_in); 1248 return; 1249 } 1250 } else if (ev->result != ISC_R_SUCCESS) { 1251 free_buffer(disp, ev->region.base, ev->region.length); 1252 1253 if (ev->result != ISC_R_CANCELED) 1254 dispatch_log(disp, ISC_LOG_ERROR, 1255 "odd socket result in udp_recv(): %s", 1256 isc_result_totext(ev->result)); 1257 1258 UNLOCK(&disp->lock); 1259 isc_event_free(&ev_in); 1260 return; 1261 } 1262 1263 /* 1264 * If this is from a blackholed address, drop it. 1265 */ 1266 isc_netaddr_fromsockaddr(&netaddr, &ev->address); 1267 if (disp->mgr->blackhole != NULL && 1268 dns_acl_match(&netaddr, NULL, disp->mgr->blackhole, 1269 NULL, &match, NULL) == ISC_R_SUCCESS && 1270 match > 0) 1271 { 1272 if (isc_log_wouldlog(dns_lctx, LVL(10))) { 1273 char netaddrstr[ISC_NETADDR_FORMATSIZE]; 1274 isc_netaddr_format(&netaddr, netaddrstr, 1275 sizeof(netaddrstr)); 1276 dispatch_log(disp, LVL(10), 1277 "blackholed packet from %s", 1278 netaddrstr); 1279 } 1280 free_buffer(disp, ev->region.base, ev->region.length); 1281 goto restart; 1282 } 1283 1284 /* 1285 * Peek into the buffer to see what we can see. 1286 */ 1287 isc_buffer_init(&source, ev->region.base, ev->region.length); 1288 isc_buffer_add(&source, ev->n); 1289 dres = dns_message_peekheader(&source, &id, &flags); 1290 if (dres != ISC_R_SUCCESS) { 1291 free_buffer(disp, ev->region.base, ev->region.length); 1292 dispatch_log(disp, LVL(10), "got garbage packet"); 1293 goto restart; 1294 } 1295 1296 dispatch_log(disp, LVL(92), 1297 "got valid DNS message header, /QR %c, id %u", 1298 ((flags & DNS_MESSAGEFLAG_QR) ? '1' : '0'), id); 1299 1300 /* 1301 * Look at flags. If query, drop it. If response, 1302 * look to see where it goes. 1303 */ 1304 if ((flags & DNS_MESSAGEFLAG_QR) == 0) { 1305 /* query */ 1306 free_buffer(disp, ev->region.base, ev->region.length); 1307 goto restart; 1308 } 1309 1310 /* 1311 * Search for the corresponding response. If we are using an exclusive 1312 * socket, we've already identified it and we can skip the search; but 1313 * the ID and the address must match the expected ones. 1314 */ 1315 if (resp == NULL) { 1316 bucket = dns_hash(qid, &ev->address, id, disp->localport); 1317 LOCK(&qid->lock); 1318 qidlocked = ISC_TRUE; 1319 resp = entry_search(qid, &ev->address, id, disp->localport, 1320 bucket); 1321 dispatch_log(disp, LVL(90), 1322 "search for response in bucket %d: %s", 1323 bucket, (resp == NULL ? "not found" : "found")); 1324 1325 if (resp == NULL) { 1326 inc_stats(mgr, dns_resstatscounter_mismatch); 1327 free_buffer(disp, ev->region.base, ev->region.length); 1328 goto unlock; 1329 } 1330 } else if (resp->id != id || !isc_sockaddr_equal(&ev->address, 1331 &resp->host)) { 1332 dispatch_log(disp, LVL(90), 1333 "response to an exclusive socket doesn't match"); 1334 inc_stats(mgr, dns_resstatscounter_mismatch); 1335 free_buffer(disp, ev->region.base, ev->region.length); 1336 goto unlock; 1337 } 1338 1339 /* 1340 * Now that we have the original dispatch the query was sent 1341 * from check that the address and port the response was 1342 * sent to make sense. 1343 */ 1344 if (disp != resp->disp) { 1345 isc_sockaddr_t a1; 1346 isc_sockaddr_t a2; 1347 1348 /* 1349 * Check that the socket types and ports match. 1350 */ 1351 if (disp->socktype != resp->disp->socktype || 1352 isc_sockaddr_getport(&disp->local) != 1353 isc_sockaddr_getport(&resp->disp->local)) { 1354 free_buffer(disp, ev->region.base, ev->region.length); 1355 goto unlock; 1356 } 1357 1358 /* 1359 * If both dispatches are bound to an address then fail as 1360 * the addresses can't be equal (enforced by the IP stack). 1361 * 1362 * Note under Linux a packet can be sent out via IPv4 socket 1363 * and the response be received via a IPv6 socket. 1364 * 1365 * Requests sent out via IPv6 should always come back in 1366 * via IPv6. 1367 */ 1368 if (isc_sockaddr_pf(&resp->disp->local) == PF_INET6 && 1369 isc_sockaddr_pf(&disp->local) != PF_INET6) { 1370 free_buffer(disp, ev->region.base, ev->region.length); 1371 goto unlock; 1372 } 1373 isc_sockaddr_anyofpf(&a1, isc_sockaddr_pf(&resp->disp->local)); 1374 isc_sockaddr_anyofpf(&a2, isc_sockaddr_pf(&disp->local)); 1375 if (!isc_sockaddr_eqaddr(&a1, &resp->disp->local) && 1376 !isc_sockaddr_eqaddr(&a2, &disp->local)) { 1377 free_buffer(disp, ev->region.base, ev->region.length); 1378 goto unlock; 1379 } 1380 } 1381 1382 sendresponse: 1383 queue_response = resp->item_out; 1384 rev = allocate_event(resp->disp); 1385 if (rev == NULL) { 1386 free_buffer(disp, ev->region.base, ev->region.length); 1387 goto unlock; 1388 } 1389 1390 /* 1391 * At this point, rev contains the event we want to fill in, and 1392 * resp contains the information on the place to send it to. 1393 * Send the event off. 1394 */ 1395 isc_buffer_init(&rev->buffer, ev->region.base, ev->region.length); 1396 isc_buffer_add(&rev->buffer, ev->n); 1397 rev->result = ev->result; 1398 rev->id = id; 1399 rev->addr = ev->address; 1400 rev->pktinfo = ev->pktinfo; 1401 rev->attributes = ev->attributes; 1402 if (queue_response) { 1403 ISC_LIST_APPEND(resp->items, rev, ev_link); 1404 } else { 1405 ISC_EVENT_INIT(rev, sizeof(*rev), 0, NULL, 1406 DNS_EVENT_DISPATCH, 1407 resp->action, resp->arg, resp, NULL, NULL); 1408 request_log(disp, resp, LVL(90), 1409 "[a] Sent event %p buffer %p len %d to task %p", 1410 rev, rev->buffer.base, rev->buffer.length, 1411 resp->task); 1412 resp->item_out = ISC_TRUE; 1413 isc_task_send(resp->task, ISC_EVENT_PTR(&rev)); 1414 } 1415 unlock: 1416 if (qidlocked) 1417 UNLOCK(&qid->lock); 1418 1419 /* 1420 * Restart recv() to get the next packet. 1421 */ 1422 restart: 1423 result = startrecv(disp, dispsock); 1424 if (result != ISC_R_SUCCESS && dispsock != NULL) { 1425 /* 1426 * XXX: wired. There seems to be no recovery process other than 1427 * deactivate this socket anyway (since we cannot start 1428 * receiving, we won't be able to receive a cancel event 1429 * from the user). 1430 */ 1431 deactivate_dispsocket(disp, dispsock); 1432 } 1433 UNLOCK(&disp->lock); 1434 1435 isc_event_free(&ev_in); 1436} 1437 1438/* 1439 * General flow: 1440 * 1441 * If I/O result == CANCELED, EOF, or error, notify everyone as the 1442 * various queues drain. 1443 * 1444 * If query, restart. 1445 * 1446 * If response: 1447 * Allocate event, fill in details. 1448 * If cannot allocate, restart. 1449 * find target. If not found, restart. 1450 * if event queue is not empty, queue. else, send. 1451 * restart. 1452 */ 1453static void 1454tcp_recv(isc_task_t *task, isc_event_t *ev_in) { 1455 dns_dispatch_t *disp = ev_in->ev_arg; 1456 dns_tcpmsg_t *tcpmsg = &disp->tcpmsg; 1457 dns_messageid_t id; 1458 isc_result_t dres; 1459 unsigned int flags; 1460 dns_dispentry_t *resp; 1461 dns_dispatchevent_t *rev; 1462 unsigned int bucket; 1463 isc_boolean_t killit; 1464 isc_boolean_t queue_response; 1465 dns_qid_t *qid; 1466 int level; 1467 char buf[ISC_SOCKADDR_FORMATSIZE]; 1468 1469 UNUSED(task); 1470 1471 REQUIRE(VALID_DISPATCH(disp)); 1472 1473 qid = disp->qid; 1474 1475 dispatch_log(disp, LVL(90), 1476 "got TCP packet: requests %d, buffers %d, recvs %d", 1477 disp->requests, disp->tcpbuffers, disp->recv_pending); 1478 1479 LOCK(&disp->lock); 1480 1481 INSIST(disp->recv_pending != 0); 1482 disp->recv_pending = 0; 1483 1484 if (disp->refcount == 0) { 1485 /* 1486 * This dispatcher is shutting down. Force cancelation. 1487 */ 1488 tcpmsg->result = ISC_R_CANCELED; 1489 } 1490 1491 if (tcpmsg->result != ISC_R_SUCCESS) { 1492 switch (tcpmsg->result) { 1493 case ISC_R_CANCELED: 1494 break; 1495 1496 case ISC_R_EOF: 1497 dispatch_log(disp, LVL(90), "shutting down on EOF"); 1498 do_cancel(disp); 1499 break; 1500 1501 case ISC_R_CONNECTIONRESET: 1502 level = ISC_LOG_INFO; 1503 goto logit; 1504 1505 default: 1506 level = ISC_LOG_ERROR; 1507 logit: 1508 isc_sockaddr_format(&tcpmsg->address, buf, sizeof(buf)); 1509 dispatch_log(disp, level, "shutting down due to TCP " 1510 "receive error: %s: %s", buf, 1511 isc_result_totext(tcpmsg->result)); 1512 do_cancel(disp); 1513 break; 1514 } 1515 1516 /* 1517 * The event is statically allocated in the tcpmsg 1518 * structure, and destroy_disp() frees the tcpmsg, so we must 1519 * free the event *before* calling destroy_disp(). 1520 */ 1521 isc_event_free(&ev_in); 1522 1523 disp->shutting_down = 1; 1524 disp->shutdown_why = tcpmsg->result; 1525 1526 /* 1527 * If the recv() was canceled pass the word on. 1528 */ 1529 killit = destroy_disp_ok(disp); 1530 UNLOCK(&disp->lock); 1531 if (killit) 1532 isc_task_send(disp->task[0], &disp->ctlevent); 1533 return; 1534 } 1535 1536 dispatch_log(disp, LVL(90), "result %d, length == %d, addr = %p", 1537 tcpmsg->result, 1538 tcpmsg->buffer.length, tcpmsg->buffer.base); 1539 1540 /* 1541 * Peek into the buffer to see what we can see. 1542 */ 1543 dres = dns_message_peekheader(&tcpmsg->buffer, &id, &flags); 1544 if (dres != ISC_R_SUCCESS) { 1545 dispatch_log(disp, LVL(10), "got garbage packet"); 1546 goto restart; 1547 } 1548 1549 dispatch_log(disp, LVL(92), 1550 "got valid DNS message header, /QR %c, id %u", 1551 ((flags & DNS_MESSAGEFLAG_QR) ? '1' : '0'), id); 1552 1553 /* 1554 * Allocate an event to send to the query or response client, and 1555 * allocate a new buffer for our use. 1556 */ 1557 1558 /* 1559 * Look at flags. If query, drop it. If response, 1560 * look to see where it goes. 1561 */ 1562 if ((flags & DNS_MESSAGEFLAG_QR) == 0) { 1563 /* 1564 * Query. 1565 */ 1566 goto restart; 1567 } 1568 1569 /* 1570 * Response. 1571 */ 1572 bucket = dns_hash(qid, &tcpmsg->address, id, disp->localport); 1573 LOCK(&qid->lock); 1574 resp = entry_search(qid, &tcpmsg->address, id, disp->localport, bucket); 1575 dispatch_log(disp, LVL(90), 1576 "search for response in bucket %d: %s", 1577 bucket, (resp == NULL ? "not found" : "found")); 1578 1579 if (resp == NULL) 1580 goto unlock; 1581 queue_response = resp->item_out; 1582 rev = allocate_event(disp); 1583 if (rev == NULL) 1584 goto unlock; 1585 1586 /* 1587 * At this point, rev contains the event we want to fill in, and 1588 * resp contains the information on the place to send it to. 1589 * Send the event off. 1590 */ 1591 dns_tcpmsg_keepbuffer(tcpmsg, &rev->buffer); 1592 disp->tcpbuffers++; 1593 rev->result = ISC_R_SUCCESS; 1594 rev->id = id; 1595 rev->addr = tcpmsg->address; 1596 if (queue_response) { 1597 ISC_LIST_APPEND(resp->items, rev, ev_link); 1598 } else { 1599 ISC_EVENT_INIT(rev, sizeof(*rev), 0, NULL, DNS_EVENT_DISPATCH, 1600 resp->action, resp->arg, resp, NULL, NULL); 1601 request_log(disp, resp, LVL(90), 1602 "[b] Sent event %p buffer %p len %d to task %p", 1603 rev, rev->buffer.base, rev->buffer.length, 1604 resp->task); 1605 resp->item_out = ISC_TRUE; 1606 isc_task_send(resp->task, ISC_EVENT_PTR(&rev)); 1607 } 1608 unlock: 1609 UNLOCK(&qid->lock); 1610 1611 /* 1612 * Restart recv() to get the next packet. 1613 */ 1614 restart: 1615 (void)startrecv(disp, NULL); 1616 1617 UNLOCK(&disp->lock); 1618 1619 isc_event_free(&ev_in); 1620} 1621 1622/* 1623 * disp must be locked. 1624 */ 1625static isc_result_t 1626startrecv(dns_dispatch_t *disp, dispsocket_t *dispsock) { 1627 isc_result_t res; 1628 isc_region_t region; 1629 isc_socket_t *socket; 1630 1631 if (disp->shutting_down == 1) 1632 return (ISC_R_SUCCESS); 1633 1634 if ((disp->attributes & DNS_DISPATCHATTR_NOLISTEN) != 0) 1635 return (ISC_R_SUCCESS); 1636 1637 if (disp->recv_pending != 0 && dispsock == NULL) 1638 return (ISC_R_SUCCESS); 1639 1640 if (disp->mgr->buffers >= disp->mgr->maxbuffers) 1641 return (ISC_R_NOMEMORY); 1642 1643 if ((disp->attributes & DNS_DISPATCHATTR_EXCLUSIVE) != 0 && 1644 dispsock == NULL) 1645 return (ISC_R_SUCCESS); 1646 1647 if (dispsock != NULL) 1648 socket = dispsock->socket; 1649 else 1650 socket = disp->socket; 1651 INSIST(socket != NULL); 1652 1653 switch (disp->socktype) { 1654 /* 1655 * UDP reads are always maximal. 1656 */ 1657 case isc_sockettype_udp: 1658 region.length = disp->mgr->buffersize; 1659 region.base = allocate_udp_buffer(disp); 1660 if (region.base == NULL) 1661 return (ISC_R_NOMEMORY); 1662 if (dispsock != NULL) { 1663 res = isc_socket_recv(socket, ®ion, 1, 1664 dispsock->task, udp_exrecv, 1665 dispsock); 1666 if (res != ISC_R_SUCCESS) { 1667 free_buffer(disp, region.base, region.length); 1668 return (res); 1669 } 1670 } else { 1671 res = isc_socket_recv(socket, ®ion, 1, 1672 disp->task[0], udp_shrecv, disp); 1673 if (res != ISC_R_SUCCESS) { 1674 free_buffer(disp, region.base, region.length); 1675 disp->shutdown_why = res; 1676 disp->shutting_down = 1; 1677 do_cancel(disp); 1678 return (ISC_R_SUCCESS); /* recover by cancel */ 1679 } 1680 INSIST(disp->recv_pending == 0); 1681 disp->recv_pending = 1; 1682 } 1683 break; 1684 1685 case isc_sockettype_tcp: 1686 res = dns_tcpmsg_readmessage(&disp->tcpmsg, disp->task[0], 1687 tcp_recv, disp); 1688 if (res != ISC_R_SUCCESS) { 1689 disp->shutdown_why = res; 1690 disp->shutting_down = 1; 1691 do_cancel(disp); 1692 return (ISC_R_SUCCESS); /* recover by cancel */ 1693 } 1694 INSIST(disp->recv_pending == 0); 1695 disp->recv_pending = 1; 1696 break; 1697 default: 1698 INSIST(0); 1699 break; 1700 } 1701 1702 return (ISC_R_SUCCESS); 1703} 1704 1705/* 1706 * Mgr must be locked when calling this function. 1707 */ 1708static isc_boolean_t 1709destroy_mgr_ok(dns_dispatchmgr_t *mgr) { 1710 mgr_log(mgr, LVL(90), 1711 "destroy_mgr_ok: shuttingdown=%d, listnonempty=%d, " 1712 "epool=%d, rpool=%d, dpool=%d", 1713 MGR_IS_SHUTTINGDOWN(mgr), !ISC_LIST_EMPTY(mgr->list), 1714 isc_mempool_getallocated(mgr->epool), 1715 isc_mempool_getallocated(mgr->rpool), 1716 isc_mempool_getallocated(mgr->dpool)); 1717 if (!MGR_IS_SHUTTINGDOWN(mgr)) 1718 return (ISC_FALSE); 1719 if (!ISC_LIST_EMPTY(mgr->list)) 1720 return (ISC_FALSE); 1721 if (isc_mempool_getallocated(mgr->epool) != 0) 1722 return (ISC_FALSE); 1723 if (isc_mempool_getallocated(mgr->rpool) != 0) 1724 return (ISC_FALSE); 1725 if (isc_mempool_getallocated(mgr->dpool) != 0) 1726 return (ISC_FALSE); 1727 1728 return (ISC_TRUE); 1729} 1730 1731/* 1732 * Mgr must be unlocked when calling this function. 1733 */ 1734static void 1735destroy_mgr(dns_dispatchmgr_t **mgrp) { 1736 isc_mem_t *mctx; 1737 dns_dispatchmgr_t *mgr; 1738 1739 mgr = *mgrp; 1740 *mgrp = NULL; 1741 1742 mctx = mgr->mctx; 1743 1744 mgr->magic = 0; 1745 mgr->mctx = NULL; 1746 DESTROYLOCK(&mgr->lock); 1747 mgr->state = 0; 1748 1749 DESTROYLOCK(&mgr->arc4_lock); 1750 1751 isc_mempool_destroy(&mgr->epool); 1752 isc_mempool_destroy(&mgr->rpool); 1753 isc_mempool_destroy(&mgr->dpool); 1754 if (mgr->bpool != NULL) 1755 isc_mempool_destroy(&mgr->bpool); 1756 if (mgr->spool != NULL) 1757 isc_mempool_destroy(&mgr->spool); 1758 1759 DESTROYLOCK(&mgr->pool_lock); 1760 1761#ifdef BIND9 1762 if (mgr->entropy != NULL) 1763 isc_entropy_detach(&mgr->entropy); 1764#endif /* BIND9 */ 1765 if (mgr->qid != NULL) 1766 qid_destroy(mctx, &mgr->qid); 1767 1768 DESTROYLOCK(&mgr->buffer_lock); 1769 1770 if (mgr->blackhole != NULL) 1771 dns_acl_detach(&mgr->blackhole); 1772 1773 if (mgr->stats != NULL) 1774 isc_stats_detach(&mgr->stats); 1775 1776 if (mgr->v4ports != NULL) { 1777 isc_mem_put(mctx, mgr->v4ports, 1778 mgr->nv4ports * sizeof(in_port_t)); 1779 } 1780 if (mgr->v6ports != NULL) { 1781 isc_mem_put(mctx, mgr->v6ports, 1782 mgr->nv6ports * sizeof(in_port_t)); 1783 } 1784 isc_mem_put(mctx, mgr, sizeof(dns_dispatchmgr_t)); 1785 isc_mem_detach(&mctx); 1786} 1787 1788static isc_result_t 1789open_socket(isc_socketmgr_t *mgr, isc_sockaddr_t *local, 1790 unsigned int options, isc_socket_t **sockp) 1791{ 1792 isc_socket_t *sock; 1793 isc_result_t result; 1794 1795 sock = *sockp; 1796 if (sock == NULL) { 1797 result = isc_socket_create(mgr, isc_sockaddr_pf(local), 1798 isc_sockettype_udp, &sock); 1799 if (result != ISC_R_SUCCESS) 1800 return (result); 1801 isc_socket_setname(sock, "dispatcher", NULL); 1802 } else { 1803#ifdef BIND9 1804 result = isc_socket_open(sock); 1805 if (result != ISC_R_SUCCESS) 1806 return (result); 1807#else 1808 INSIST(0); 1809#endif 1810 } 1811 1812#ifndef ISC_ALLOW_MAPPED 1813 isc_socket_ipv6only(sock, ISC_TRUE); 1814#endif 1815 result = isc_socket_bind(sock, local, options); 1816 if (result != ISC_R_SUCCESS) { 1817 if (*sockp == NULL) 1818 isc_socket_detach(&sock); 1819 else { 1820#ifdef BIND9 1821 isc_socket_close(sock); 1822#else 1823 INSIST(0); 1824#endif 1825 } 1826 return (result); 1827 } 1828 1829 *sockp = sock; 1830 return (ISC_R_SUCCESS); 1831} 1832 1833/*% 1834 * Create a temporary port list to set the initial default set of dispatch 1835 * ports: [1024, 65535]. This is almost meaningless as the application will 1836 * normally set the ports explicitly, but is provided to fill some minor corner 1837 * cases. 1838 */ 1839static isc_result_t 1840create_default_portset(isc_mem_t *mctx, isc_portset_t **portsetp) { 1841 isc_result_t result; 1842 1843 result = isc_portset_create(mctx, portsetp); 1844 if (result != ISC_R_SUCCESS) 1845 return (result); 1846 isc_portset_addrange(*portsetp, 1024, 65535); 1847 1848 return (ISC_R_SUCCESS); 1849} 1850 1851/* 1852 * Publics. 1853 */ 1854 1855isc_result_t 1856dns_dispatchmgr_create(isc_mem_t *mctx, isc_entropy_t *entropy, 1857 dns_dispatchmgr_t **mgrp) 1858{ 1859 dns_dispatchmgr_t *mgr; 1860 isc_result_t result; 1861 isc_portset_t *v4portset = NULL; 1862 isc_portset_t *v6portset = NULL; 1863 1864 REQUIRE(mctx != NULL); 1865 REQUIRE(mgrp != NULL && *mgrp == NULL); 1866 1867 mgr = isc_mem_get(mctx, sizeof(dns_dispatchmgr_t)); 1868 if (mgr == NULL) 1869 return (ISC_R_NOMEMORY); 1870 1871 mgr->mctx = NULL; 1872 isc_mem_attach(mctx, &mgr->mctx); 1873 1874 mgr->blackhole = NULL; 1875 mgr->stats = NULL; 1876 1877 result = isc_mutex_init(&mgr->lock); 1878 if (result != ISC_R_SUCCESS) 1879 goto deallocate; 1880 1881 result = isc_mutex_init(&mgr->arc4_lock); 1882 if (result != ISC_R_SUCCESS) 1883 goto kill_lock; 1884 1885 result = isc_mutex_init(&mgr->buffer_lock); 1886 if (result != ISC_R_SUCCESS) 1887 goto kill_arc4_lock; 1888 1889 result = isc_mutex_init(&mgr->pool_lock); 1890 if (result != ISC_R_SUCCESS) 1891 goto kill_buffer_lock; 1892 1893 mgr->epool = NULL; 1894 if (isc_mempool_create(mgr->mctx, sizeof(dns_dispatchevent_t), 1895 &mgr->epool) != ISC_R_SUCCESS) { 1896 result = ISC_R_NOMEMORY; 1897 goto kill_pool_lock; 1898 } 1899 1900 mgr->rpool = NULL; 1901 if (isc_mempool_create(mgr->mctx, sizeof(dns_dispentry_t), 1902 &mgr->rpool) != ISC_R_SUCCESS) { 1903 result = ISC_R_NOMEMORY; 1904 goto kill_epool; 1905 } 1906 1907 mgr->dpool = NULL; 1908 if (isc_mempool_create(mgr->mctx, sizeof(dns_dispatch_t), 1909 &mgr->dpool) != ISC_R_SUCCESS) { 1910 result = ISC_R_NOMEMORY; 1911 goto kill_rpool; 1912 } 1913 1914 isc_mempool_setname(mgr->epool, "dispmgr_epool"); 1915 isc_mempool_setfreemax(mgr->epool, 1024); 1916 isc_mempool_associatelock(mgr->epool, &mgr->pool_lock); 1917 1918 isc_mempool_setname(mgr->rpool, "dispmgr_rpool"); 1919 isc_mempool_setfreemax(mgr->rpool, 1024); 1920 isc_mempool_associatelock(mgr->rpool, &mgr->pool_lock); 1921 1922 isc_mempool_setname(mgr->dpool, "dispmgr_dpool"); 1923 isc_mempool_setfreemax(mgr->dpool, 1024); 1924 isc_mempool_associatelock(mgr->dpool, &mgr->pool_lock); 1925 1926 mgr->buffers = 0; 1927 mgr->buffersize = 0; 1928 mgr->maxbuffers = 0; 1929 mgr->bpool = NULL; 1930 mgr->spool = NULL; 1931 mgr->entropy = NULL; 1932 mgr->qid = NULL; 1933 mgr->state = 0; 1934 ISC_LIST_INIT(mgr->list); 1935 mgr->v4ports = NULL; 1936 mgr->v6ports = NULL; 1937 mgr->nv4ports = 0; 1938 mgr->nv6ports = 0; 1939 mgr->magic = DNS_DISPATCHMGR_MAGIC; 1940 1941 result = create_default_portset(mctx, &v4portset); 1942 if (result == ISC_R_SUCCESS) { 1943 result = create_default_portset(mctx, &v6portset); 1944 if (result == ISC_R_SUCCESS) { 1945 result = dns_dispatchmgr_setavailports(mgr, 1946 v4portset, 1947 v6portset); 1948 } 1949 } 1950 if (v4portset != NULL) 1951 isc_portset_destroy(mctx, &v4portset); 1952 if (v6portset != NULL) 1953 isc_portset_destroy(mctx, &v6portset); 1954 if (result != ISC_R_SUCCESS) 1955 goto kill_dpool; 1956 1957#ifdef BIND9 1958 if (entropy != NULL) 1959 isc_entropy_attach(entropy, &mgr->entropy); 1960#else 1961 UNUSED(entropy); 1962#endif 1963 1964 dispatch_initrandom(&mgr->arc4ctx, mgr->entropy, &mgr->arc4_lock); 1965 1966 *mgrp = mgr; 1967 return (ISC_R_SUCCESS); 1968 1969 kill_dpool: 1970 isc_mempool_destroy(&mgr->dpool); 1971 kill_rpool: 1972 isc_mempool_destroy(&mgr->rpool); 1973 kill_epool: 1974 isc_mempool_destroy(&mgr->epool); 1975 kill_pool_lock: 1976 DESTROYLOCK(&mgr->pool_lock); 1977 kill_buffer_lock: 1978 DESTROYLOCK(&mgr->buffer_lock); 1979 kill_arc4_lock: 1980 DESTROYLOCK(&mgr->arc4_lock); 1981 kill_lock: 1982 DESTROYLOCK(&mgr->lock); 1983 deallocate: 1984 isc_mem_put(mctx, mgr, sizeof(dns_dispatchmgr_t)); 1985 isc_mem_detach(&mctx); 1986 1987 return (result); 1988} 1989 1990void 1991dns_dispatchmgr_setblackhole(dns_dispatchmgr_t *mgr, dns_acl_t *blackhole) { 1992 REQUIRE(VALID_DISPATCHMGR(mgr)); 1993 if (mgr->blackhole != NULL) 1994 dns_acl_detach(&mgr->blackhole); 1995 dns_acl_attach(blackhole, &mgr->blackhole); 1996} 1997 1998dns_acl_t * 1999dns_dispatchmgr_getblackhole(dns_dispatchmgr_t *mgr) { 2000 REQUIRE(VALID_DISPATCHMGR(mgr)); 2001 return (mgr->blackhole); 2002} 2003 2004void 2005dns_dispatchmgr_setblackportlist(dns_dispatchmgr_t *mgr, 2006 dns_portlist_t *portlist) 2007{ 2008 REQUIRE(VALID_DISPATCHMGR(mgr)); 2009 UNUSED(portlist); 2010 2011 /* This function is deprecated: use dns_dispatchmgr_setavailports(). */ 2012 return; 2013} 2014 2015dns_portlist_t * 2016dns_dispatchmgr_getblackportlist(dns_dispatchmgr_t *mgr) { 2017 REQUIRE(VALID_DISPATCHMGR(mgr)); 2018 return (NULL); /* this function is deprecated */ 2019} 2020 2021isc_result_t 2022dns_dispatchmgr_setavailports(dns_dispatchmgr_t *mgr, isc_portset_t *v4portset, 2023 isc_portset_t *v6portset) 2024{ 2025 in_port_t *v4ports, *v6ports, p; 2026 unsigned int nv4ports, nv6ports, i4, i6; 2027 2028 REQUIRE(VALID_DISPATCHMGR(mgr)); 2029 2030 nv4ports = isc_portset_nports(v4portset); 2031 nv6ports = isc_portset_nports(v6portset); 2032 2033 v4ports = NULL; 2034 if (nv4ports != 0) { 2035 v4ports = isc_mem_get(mgr->mctx, sizeof(in_port_t) * nv4ports); 2036 if (v4ports == NULL) 2037 return (ISC_R_NOMEMORY); 2038 } 2039 v6ports = NULL; 2040 if (nv6ports != 0) { 2041 v6ports = isc_mem_get(mgr->mctx, sizeof(in_port_t) * nv6ports); 2042 if (v6ports == NULL) { 2043 if (v4ports != NULL) { 2044 isc_mem_put(mgr->mctx, v4ports, 2045 sizeof(in_port_t) * 2046 isc_portset_nports(v4portset)); 2047 } 2048 return (ISC_R_NOMEMORY); 2049 } 2050 } 2051 2052 p = 0; 2053 i4 = 0; 2054 i6 = 0; 2055 do { 2056 if (isc_portset_isset(v4portset, p)) { 2057 INSIST(i4 < nv4ports); 2058 v4ports[i4++] = p; 2059 } 2060 if (isc_portset_isset(v6portset, p)) { 2061 INSIST(i6 < nv6ports); 2062 v6ports[i6++] = p; 2063 } 2064 } while (p++ < 65535); 2065 INSIST(i4 == nv4ports && i6 == nv6ports); 2066 2067 PORTBUFLOCK(mgr); 2068 if (mgr->v4ports != NULL) { 2069 isc_mem_put(mgr->mctx, mgr->v4ports, 2070 mgr->nv4ports * sizeof(in_port_t)); 2071 } 2072 mgr->v4ports = v4ports; 2073 mgr->nv4ports = nv4ports; 2074 2075 if (mgr->v6ports != NULL) { 2076 isc_mem_put(mgr->mctx, mgr->v6ports, 2077 mgr->nv6ports * sizeof(in_port_t)); 2078 } 2079 mgr->v6ports = v6ports; 2080 mgr->nv6ports = nv6ports; 2081 PORTBUFUNLOCK(mgr); 2082 2083 return (ISC_R_SUCCESS); 2084} 2085 2086static isc_result_t 2087dns_dispatchmgr_setudp(dns_dispatchmgr_t *mgr, 2088 unsigned int buffersize, unsigned int maxbuffers, 2089 unsigned int maxrequests, unsigned int buckets, 2090 unsigned int increment) 2091{ 2092 isc_result_t result; 2093 2094 REQUIRE(VALID_DISPATCHMGR(mgr)); 2095 REQUIRE(buffersize >= 512 && buffersize < (64 * 1024)); 2096 REQUIRE(maxbuffers > 0); 2097 REQUIRE(buckets < 2097169); /* next prime > 65536 * 32 */ 2098 REQUIRE(increment > buckets); 2099 2100 /* 2101 * Keep some number of items around. This should be a config 2102 * option. For now, keep 8, but later keep at least two even 2103 * if the caller wants less. This allows us to ensure certain 2104 * things, like an event can be "freed" and the next allocation 2105 * will always succeed. 2106 * 2107 * Note that if limits are placed on anything here, we use one 2108 * event internally, so the actual limit should be "wanted + 1." 2109 * 2110 * XXXMLG 2111 */ 2112 2113 if (maxbuffers < 8) 2114 maxbuffers = 8; 2115 2116 LOCK(&mgr->buffer_lock); 2117 2118 /* Create or adjust buffer pool */ 2119 if (mgr->bpool != NULL) { 2120 /* 2121 * We only increase the maxbuffers to avoid accidental buffer 2122 * shortage. Ideally we'd separate the manager-wide maximum 2123 * from per-dispatch limits and respect the latter within the 2124 * global limit. But at this moment that's deemed to be 2125 * overkilling and isn't worth additional implementation 2126 * complexity. 2127 */ 2128 if (maxbuffers > mgr->maxbuffers) { 2129 isc_mempool_setmaxalloc(mgr->bpool, maxbuffers); 2130 mgr->maxbuffers = maxbuffers; 2131 } 2132 } else { 2133 result = isc_mempool_create(mgr->mctx, buffersize, &mgr->bpool); 2134 if (result != ISC_R_SUCCESS) { 2135 UNLOCK(&mgr->buffer_lock); 2136 return (result); 2137 } 2138 isc_mempool_setname(mgr->bpool, "dispmgr_bpool"); 2139 isc_mempool_setmaxalloc(mgr->bpool, maxbuffers); 2140 isc_mempool_associatelock(mgr->bpool, &mgr->pool_lock); 2141 } 2142 2143 /* Create or adjust socket pool */ 2144 if (mgr->spool != NULL) { 2145 isc_mempool_setmaxalloc(mgr->spool, DNS_DISPATCH_POOLSOCKS * 2); 2146 UNLOCK(&mgr->buffer_lock); 2147 return (ISC_R_SUCCESS); 2148 } 2149 result = isc_mempool_create(mgr->mctx, sizeof(dispsocket_t), 2150 &mgr->spool); 2151 if (result != ISC_R_SUCCESS) { 2152 UNLOCK(&mgr->buffer_lock); 2153 goto cleanup; 2154 } 2155 isc_mempool_setname(mgr->spool, "dispmgr_spool"); 2156 isc_mempool_setmaxalloc(mgr->spool, maxrequests); 2157 isc_mempool_associatelock(mgr->spool, &mgr->pool_lock); 2158 2159 result = qid_allocate(mgr, buckets, increment, &mgr->qid, ISC_TRUE); 2160 if (result != ISC_R_SUCCESS) 2161 goto cleanup; 2162 2163 mgr->buffersize = buffersize; 2164 mgr->maxbuffers = maxbuffers; 2165 UNLOCK(&mgr->buffer_lock); 2166 return (ISC_R_SUCCESS); 2167 2168 cleanup: 2169 isc_mempool_destroy(&mgr->bpool); 2170 if (mgr->spool != NULL) 2171 isc_mempool_destroy(&mgr->spool); 2172 UNLOCK(&mgr->buffer_lock); 2173 return (result); 2174} 2175 2176void 2177dns_dispatchmgr_destroy(dns_dispatchmgr_t **mgrp) { 2178 dns_dispatchmgr_t *mgr; 2179 isc_boolean_t killit; 2180 2181 REQUIRE(mgrp != NULL); 2182 REQUIRE(VALID_DISPATCHMGR(*mgrp)); 2183 2184 mgr = *mgrp; 2185 *mgrp = NULL; 2186 2187 LOCK(&mgr->lock); 2188 mgr->state |= MGR_SHUTTINGDOWN; 2189 2190 killit = destroy_mgr_ok(mgr); 2191 UNLOCK(&mgr->lock); 2192 2193 mgr_log(mgr, LVL(90), "destroy: killit=%d", killit); 2194 2195 if (killit) 2196 destroy_mgr(&mgr); 2197} 2198 2199void 2200dns_dispatchmgr_setstats(dns_dispatchmgr_t *mgr, isc_stats_t *stats) { 2201 REQUIRE(VALID_DISPATCHMGR(mgr)); 2202 REQUIRE(ISC_LIST_EMPTY(mgr->list)); 2203 REQUIRE(mgr->stats == NULL); 2204 2205 isc_stats_attach(stats, &mgr->stats); 2206} 2207 2208static int 2209port_cmp(const void *key, const void *ent) { 2210 in_port_t p1 = *(const in_port_t *)key; 2211 in_port_t p2 = *(const in_port_t *)ent; 2212 2213 if (p1 < p2) 2214 return (-1); 2215 else if (p1 == p2) 2216 return (0); 2217 else 2218 return (1); 2219} 2220 2221static isc_boolean_t 2222portavailable(dns_dispatchmgr_t *mgr, isc_socket_t *sock, 2223 isc_sockaddr_t *sockaddrp) 2224{ 2225 isc_sockaddr_t sockaddr; 2226 isc_result_t result; 2227 in_port_t *ports, port; 2228 unsigned int nports; 2229 isc_boolean_t available = ISC_FALSE; 2230 2231 REQUIRE(sock != NULL || sockaddrp != NULL); 2232 2233 PORTBUFLOCK(mgr); 2234 if (sock != NULL) { 2235 sockaddrp = &sockaddr; 2236 result = isc_socket_getsockname(sock, sockaddrp); 2237 if (result != ISC_R_SUCCESS) 2238 goto unlock; 2239 } 2240 2241 if (isc_sockaddr_pf(sockaddrp) == AF_INET) { 2242 ports = mgr->v4ports; 2243 nports = mgr->nv4ports; 2244 } else { 2245 ports = mgr->v6ports; 2246 nports = mgr->nv6ports; 2247 } 2248 if (ports == NULL) 2249 goto unlock; 2250 2251 port = isc_sockaddr_getport(sockaddrp); 2252 if (bsearch(&port, ports, nports, sizeof(in_port_t), port_cmp) != NULL) 2253 available = ISC_TRUE; 2254 2255unlock: 2256 PORTBUFUNLOCK(mgr); 2257 return (available); 2258} 2259 2260#define ATTRMATCH(_a1, _a2, _mask) (((_a1) & (_mask)) == ((_a2) & (_mask))) 2261 2262static isc_boolean_t 2263local_addr_match(dns_dispatch_t *disp, isc_sockaddr_t *addr) { 2264 isc_sockaddr_t sockaddr; 2265 isc_result_t result; 2266 2267 REQUIRE(disp->socket != NULL); 2268 2269 if (addr == NULL) 2270 return (ISC_TRUE); 2271 2272 /* 2273 * Don't match wildcard ports unless the port is available in the 2274 * current configuration. 2275 */ 2276 if (isc_sockaddr_getport(addr) == 0 && 2277 isc_sockaddr_getport(&disp->local) == 0 && 2278 !portavailable(disp->mgr, disp->socket, NULL)) { 2279 return (ISC_FALSE); 2280 } 2281 2282 /* 2283 * Check if we match the binding <address,port>. 2284 * Wildcard ports match/fail here. 2285 */ 2286 if (isc_sockaddr_equal(&disp->local, addr)) 2287 return (ISC_TRUE); 2288 if (isc_sockaddr_getport(addr) == 0) 2289 return (ISC_FALSE); 2290 2291 /* 2292 * Check if we match a bound wildcard port <address,port>. 2293 */ 2294 if (!isc_sockaddr_eqaddr(&disp->local, addr)) 2295 return (ISC_FALSE); 2296 result = isc_socket_getsockname(disp->socket, &sockaddr); 2297 if (result != ISC_R_SUCCESS) 2298 return (ISC_FALSE); 2299 2300 return (isc_sockaddr_equal(&sockaddr, addr)); 2301} 2302 2303/* 2304 * Requires mgr be locked. 2305 * 2306 * No dispatcher can be locked by this thread when calling this function. 2307 * 2308 * 2309 * NOTE: 2310 * If a matching dispatcher is found, it is locked after this function 2311 * returns, and must be unlocked by the caller. 2312 */ 2313static isc_result_t 2314dispatch_find(dns_dispatchmgr_t *mgr, isc_sockaddr_t *local, 2315 unsigned int attributes, unsigned int mask, 2316 dns_dispatch_t **dispp) 2317{ 2318 dns_dispatch_t *disp; 2319 isc_result_t result; 2320 2321 /* 2322 * Make certain that we will not match a private or exclusive dispatch. 2323 */ 2324 attributes &= ~(DNS_DISPATCHATTR_PRIVATE|DNS_DISPATCHATTR_EXCLUSIVE); 2325 mask |= (DNS_DISPATCHATTR_PRIVATE|DNS_DISPATCHATTR_EXCLUSIVE); 2326 2327 disp = ISC_LIST_HEAD(mgr->list); 2328 while (disp != NULL) { 2329 LOCK(&disp->lock); 2330 if ((disp->shutting_down == 0) 2331 && ATTRMATCH(disp->attributes, attributes, mask) 2332 && local_addr_match(disp, local)) 2333 break; 2334 UNLOCK(&disp->lock); 2335 disp = ISC_LIST_NEXT(disp, link); 2336 } 2337 2338 if (disp == NULL) { 2339 result = ISC_R_NOTFOUND; 2340 goto out; 2341 } 2342 2343 *dispp = disp; 2344 result = ISC_R_SUCCESS; 2345 out: 2346 2347 return (result); 2348} 2349 2350static isc_result_t 2351qid_allocate(dns_dispatchmgr_t *mgr, unsigned int buckets, 2352 unsigned int increment, dns_qid_t **qidp, 2353 isc_boolean_t needsocktable) 2354{ 2355 dns_qid_t *qid; 2356 unsigned int i; 2357 isc_result_t result; 2358 2359 REQUIRE(VALID_DISPATCHMGR(mgr)); 2360 REQUIRE(buckets < 2097169); /* next prime > 65536 * 32 */ 2361 REQUIRE(increment > buckets); 2362 REQUIRE(qidp != NULL && *qidp == NULL); 2363 2364 qid = isc_mem_get(mgr->mctx, sizeof(*qid)); 2365 if (qid == NULL) 2366 return (ISC_R_NOMEMORY); 2367 2368 qid->qid_table = isc_mem_get(mgr->mctx, 2369 buckets * sizeof(dns_displist_t)); 2370 if (qid->qid_table == NULL) { 2371 isc_mem_put(mgr->mctx, qid, sizeof(*qid)); 2372 return (ISC_R_NOMEMORY); 2373 } 2374 2375 qid->sock_table = NULL; 2376 if (needsocktable) { 2377 qid->sock_table = isc_mem_get(mgr->mctx, buckets * 2378 sizeof(dispsocketlist_t)); 2379 if (qid->sock_table == NULL) { 2380 isc_mem_put(mgr->mctx, qid->qid_table, 2381 buckets * sizeof(dns_displist_t)); 2382 isc_mem_put(mgr->mctx, qid, sizeof(*qid)); 2383 return (ISC_R_NOMEMORY); 2384 } 2385 } 2386 2387 result = isc_mutex_init(&qid->lock); 2388 if (result != ISC_R_SUCCESS) { 2389 if (qid->sock_table != NULL) { 2390 isc_mem_put(mgr->mctx, qid->sock_table, 2391 buckets * sizeof(dispsocketlist_t)); 2392 } 2393 isc_mem_put(mgr->mctx, qid->qid_table, 2394 buckets * sizeof(dns_displist_t)); 2395 isc_mem_put(mgr->mctx, qid, sizeof(*qid)); 2396 return (result); 2397 } 2398 2399 for (i = 0; i < buckets; i++) { 2400 ISC_LIST_INIT(qid->qid_table[i]); 2401 if (qid->sock_table != NULL) 2402 ISC_LIST_INIT(qid->sock_table[i]); 2403 } 2404 2405 qid->qid_nbuckets = buckets; 2406 qid->qid_increment = increment; 2407 qid->magic = QID_MAGIC; 2408 *qidp = qid; 2409 return (ISC_R_SUCCESS); 2410} 2411 2412static void 2413qid_destroy(isc_mem_t *mctx, dns_qid_t **qidp) { 2414 dns_qid_t *qid; 2415 2416 REQUIRE(qidp != NULL); 2417 qid = *qidp; 2418 2419 REQUIRE(VALID_QID(qid)); 2420 2421 *qidp = NULL; 2422 qid->magic = 0; 2423 isc_mem_put(mctx, qid->qid_table, 2424 qid->qid_nbuckets * sizeof(dns_displist_t)); 2425 if (qid->sock_table != NULL) { 2426 isc_mem_put(mctx, qid->sock_table, 2427 qid->qid_nbuckets * sizeof(dispsocketlist_t)); 2428 } 2429 DESTROYLOCK(&qid->lock); 2430 isc_mem_put(mctx, qid, sizeof(*qid)); 2431} 2432 2433/* 2434 * Allocate and set important limits. 2435 */ 2436static isc_result_t 2437dispatch_allocate(dns_dispatchmgr_t *mgr, unsigned int maxrequests, 2438 dns_dispatch_t **dispp) 2439{ 2440 dns_dispatch_t *disp; 2441 isc_result_t result; 2442 2443 REQUIRE(VALID_DISPATCHMGR(mgr)); 2444 REQUIRE(dispp != NULL && *dispp == NULL); 2445 2446 /* 2447 * Set up the dispatcher, mostly. Don't bother setting some of 2448 * the options that are controlled by tcp vs. udp, etc. 2449 */ 2450 2451 disp = isc_mempool_get(mgr->dpool); 2452 if (disp == NULL) 2453 return (ISC_R_NOMEMORY); 2454 2455 disp->magic = 0; 2456 disp->mgr = mgr; 2457 disp->maxrequests = maxrequests; 2458 disp->attributes = 0; 2459 ISC_LINK_INIT(disp, link); 2460 disp->refcount = 1; 2461 disp->recv_pending = 0; 2462 memset(&disp->local, 0, sizeof(disp->local)); 2463 disp->localport = 0; 2464 disp->shutting_down = 0; 2465 disp->shutdown_out = 0; 2466 disp->connected = 0; 2467 disp->tcpmsg_valid = 0; 2468 disp->shutdown_why = ISC_R_UNEXPECTED; 2469 disp->requests = 0; 2470 disp->tcpbuffers = 0; 2471 disp->qid = NULL; 2472 ISC_LIST_INIT(disp->activesockets); 2473 ISC_LIST_INIT(disp->inactivesockets); 2474 disp->nsockets = 0; 2475 dispatch_initrandom(&disp->arc4ctx, mgr->entropy, NULL); 2476 disp->port_table = NULL; 2477 disp->portpool = NULL; 2478 2479 result = isc_mutex_init(&disp->lock); 2480 if (result != ISC_R_SUCCESS) 2481 goto deallocate; 2482 2483 disp->failsafe_ev = allocate_event(disp); 2484 if (disp->failsafe_ev == NULL) { 2485 result = ISC_R_NOMEMORY; 2486 goto kill_lock; 2487 } 2488 2489 disp->magic = DISPATCH_MAGIC; 2490 2491 *dispp = disp; 2492 return (ISC_R_SUCCESS); 2493 2494 /* 2495 * error returns 2496 */ 2497 kill_lock: 2498 DESTROYLOCK(&disp->lock); 2499 deallocate: 2500 isc_mempool_put(mgr->dpool, disp); 2501 2502 return (result); 2503} 2504 2505 2506/* 2507 * MUST be unlocked, and not used by anything. 2508 */ 2509static void 2510dispatch_free(dns_dispatch_t **dispp) 2511{ 2512 dns_dispatch_t *disp; 2513 dns_dispatchmgr_t *mgr; 2514 int i; 2515 2516 REQUIRE(VALID_DISPATCH(*dispp)); 2517 disp = *dispp; 2518 *dispp = NULL; 2519 2520 mgr = disp->mgr; 2521 REQUIRE(VALID_DISPATCHMGR(mgr)); 2522 2523 if (disp->tcpmsg_valid) { 2524 dns_tcpmsg_invalidate(&disp->tcpmsg); 2525 disp->tcpmsg_valid = 0; 2526 } 2527 2528 INSIST(disp->tcpbuffers == 0); 2529 INSIST(disp->requests == 0); 2530 INSIST(disp->recv_pending == 0); 2531 INSIST(ISC_LIST_EMPTY(disp->activesockets)); 2532 INSIST(ISC_LIST_EMPTY(disp->inactivesockets)); 2533 2534 isc_mempool_put(mgr->epool, disp->failsafe_ev); 2535 disp->failsafe_ev = NULL; 2536 2537 if (disp->qid != NULL) 2538 qid_destroy(mgr->mctx, &disp->qid); 2539 2540 if (disp->port_table != NULL) { 2541 for (i = 0; i < DNS_DISPATCH_PORTTABLESIZE; i++) 2542 INSIST(ISC_LIST_EMPTY(disp->port_table[i])); 2543 isc_mem_put(mgr->mctx, disp->port_table, 2544 sizeof(disp->port_table[0]) * 2545 DNS_DISPATCH_PORTTABLESIZE); 2546 } 2547 2548 if (disp->portpool != NULL) 2549 isc_mempool_destroy(&disp->portpool); 2550 2551 disp->mgr = NULL; 2552 DESTROYLOCK(&disp->lock); 2553 disp->magic = 0; 2554 isc_mempool_put(mgr->dpool, disp); 2555} 2556 2557isc_result_t 2558dns_dispatch_createtcp(dns_dispatchmgr_t *mgr, isc_socket_t *sock, 2559 isc_taskmgr_t *taskmgr, unsigned int buffersize, 2560 unsigned int maxbuffers, unsigned int maxrequests, 2561 unsigned int buckets, unsigned int increment, 2562 unsigned int attributes, dns_dispatch_t **dispp) 2563{ 2564 isc_result_t result; 2565 dns_dispatch_t *disp; 2566 2567 UNUSED(maxbuffers); 2568 UNUSED(buffersize); 2569 2570 REQUIRE(VALID_DISPATCHMGR(mgr)); 2571 REQUIRE(isc_socket_gettype(sock) == isc_sockettype_tcp); 2572 REQUIRE((attributes & DNS_DISPATCHATTR_TCP) != 0); 2573 REQUIRE((attributes & DNS_DISPATCHATTR_UDP) == 0); 2574 2575 attributes |= DNS_DISPATCHATTR_PRIVATE; /* XXXMLG */ 2576 2577 LOCK(&mgr->lock); 2578 2579 /* 2580 * dispatch_allocate() checks mgr for us. 2581 * qid_allocate() checks buckets and increment for us. 2582 */ 2583 disp = NULL; 2584 result = dispatch_allocate(mgr, maxrequests, &disp); 2585 if (result != ISC_R_SUCCESS) { 2586 UNLOCK(&mgr->lock); 2587 return (result); 2588 } 2589 2590 result = qid_allocate(mgr, buckets, increment, &disp->qid, ISC_FALSE); 2591 if (result != ISC_R_SUCCESS) 2592 goto deallocate_dispatch; 2593 2594 disp->socktype = isc_sockettype_tcp; 2595 disp->socket = NULL; 2596 isc_socket_attach(sock, &disp->socket); 2597 2598 disp->ntasks = 1; 2599 disp->task[0] = NULL; 2600 result = isc_task_create(taskmgr, 0, &disp->task[0]); 2601 if (result != ISC_R_SUCCESS) 2602 goto kill_socket; 2603 2604 disp->ctlevent = isc_event_allocate(mgr->mctx, disp, 2605 DNS_EVENT_DISPATCHCONTROL, 2606 destroy_disp, disp, 2607 sizeof(isc_event_t)); 2608 if (disp->ctlevent == NULL) { 2609 result = ISC_R_NOMEMORY; 2610 goto kill_task; 2611 } 2612 2613 isc_task_setname(disp->task[0], "tcpdispatch", disp); 2614 2615 dns_tcpmsg_init(mgr->mctx, disp->socket, &disp->tcpmsg); 2616 disp->tcpmsg_valid = 1; 2617 2618 disp->attributes = attributes; 2619 2620 /* 2621 * Append it to the dispatcher list. 2622 */ 2623 ISC_LIST_APPEND(mgr->list, disp, link); 2624 UNLOCK(&mgr->lock); 2625 2626 mgr_log(mgr, LVL(90), "created TCP dispatcher %p", disp); 2627 dispatch_log(disp, LVL(90), "created task %p", disp->task[0]); 2628 2629 *dispp = disp; 2630 2631 return (ISC_R_SUCCESS); 2632 2633 /* 2634 * Error returns. 2635 */ 2636 kill_task: 2637 isc_task_detach(&disp->task[0]); 2638 kill_socket: 2639 isc_socket_detach(&disp->socket); 2640 deallocate_dispatch: 2641 dispatch_free(&disp); 2642 2643 UNLOCK(&mgr->lock); 2644 2645 return (result); 2646} 2647 2648isc_result_t 2649dns_dispatch_getudp(dns_dispatchmgr_t *mgr, isc_socketmgr_t *sockmgr, 2650 isc_taskmgr_t *taskmgr, isc_sockaddr_t *localaddr, 2651 unsigned int buffersize, 2652 unsigned int maxbuffers, unsigned int maxrequests, 2653 unsigned int buckets, unsigned int increment, 2654 unsigned int attributes, unsigned int mask, 2655 dns_dispatch_t **dispp) 2656{ 2657 isc_result_t result; 2658 dns_dispatch_t *disp = NULL; 2659 2660 REQUIRE(VALID_DISPATCHMGR(mgr)); 2661 REQUIRE(sockmgr != NULL); 2662 REQUIRE(localaddr != NULL); 2663 REQUIRE(taskmgr != NULL); 2664 REQUIRE(buffersize >= 512 && buffersize < (64 * 1024)); 2665 REQUIRE(maxbuffers > 0); 2666 REQUIRE(buckets < 2097169); /* next prime > 65536 * 32 */ 2667 REQUIRE(increment > buckets); 2668 REQUIRE(dispp != NULL && *dispp == NULL); 2669 REQUIRE((attributes & DNS_DISPATCHATTR_TCP) == 0); 2670 2671 result = dns_dispatchmgr_setudp(mgr, buffersize, maxbuffers, 2672 maxrequests, buckets, increment); 2673 if (result != ISC_R_SUCCESS) 2674 return (result); 2675 2676 LOCK(&mgr->lock); 2677 2678 if ((attributes & DNS_DISPATCHATTR_EXCLUSIVE) != 0) { 2679 REQUIRE(isc_sockaddr_getport(localaddr) == 0); 2680 goto createudp; 2681 } 2682 2683 /* 2684 * See if we have a dispatcher that matches. 2685 */ 2686 result = dispatch_find(mgr, localaddr, attributes, mask, &disp); 2687 if (result == ISC_R_SUCCESS) { 2688 disp->refcount++; 2689 2690 if (disp->maxrequests < maxrequests) 2691 disp->maxrequests = maxrequests; 2692 2693 if ((disp->attributes & DNS_DISPATCHATTR_NOLISTEN) == 0 && 2694 (attributes & DNS_DISPATCHATTR_NOLISTEN) != 0) 2695 { 2696 disp->attributes |= DNS_DISPATCHATTR_NOLISTEN; 2697 if (disp->recv_pending != 0) 2698 isc_socket_cancel(disp->socket, disp->task[0], 2699 ISC_SOCKCANCEL_RECV); 2700 } 2701 2702 UNLOCK(&disp->lock); 2703 UNLOCK(&mgr->lock); 2704 2705 *dispp = disp; 2706 2707 return (ISC_R_SUCCESS); 2708 } 2709 2710 createudp: 2711 /* 2712 * Nope, create one. 2713 */ 2714 result = dispatch_createudp(mgr, sockmgr, taskmgr, localaddr, 2715 maxrequests, attributes, &disp); 2716 if (result != ISC_R_SUCCESS) { 2717 UNLOCK(&mgr->lock); 2718 return (result); 2719 } 2720 2721 UNLOCK(&mgr->lock); 2722 *dispp = disp; 2723 return (ISC_R_SUCCESS); 2724} 2725 2726/* 2727 * mgr should be locked. 2728 */ 2729 2730#ifndef DNS_DISPATCH_HELD 2731#define DNS_DISPATCH_HELD 20U 2732#endif 2733 2734static isc_result_t 2735get_udpsocket(dns_dispatchmgr_t *mgr, dns_dispatch_t *disp, 2736 isc_socketmgr_t *sockmgr, isc_sockaddr_t *localaddr, 2737 isc_socket_t **sockp) 2738{ 2739 unsigned int i, j; 2740 isc_socket_t *held[DNS_DISPATCH_HELD]; 2741 isc_sockaddr_t localaddr_bound; 2742 isc_socket_t *sock = NULL; 2743 isc_result_t result = ISC_R_SUCCESS; 2744 isc_boolean_t anyport; 2745 2746 INSIST(sockp != NULL && *sockp == NULL); 2747 2748 localaddr_bound = *localaddr; 2749 anyport = ISC_TF(isc_sockaddr_getport(localaddr) == 0); 2750 2751 if (anyport) { 2752 unsigned int nports; 2753 in_port_t *ports; 2754 2755 /* 2756 * If no port is specified, we first try to pick up a random 2757 * port by ourselves. 2758 */ 2759 if (isc_sockaddr_pf(localaddr) == AF_INET) { 2760 nports = disp->mgr->nv4ports; 2761 ports = disp->mgr->v4ports; 2762 } else { 2763 nports = disp->mgr->nv6ports; 2764 ports = disp->mgr->v6ports; 2765 } 2766 if (nports == 0) 2767 return (ISC_R_ADDRNOTAVAIL); 2768 2769 for (i = 0; i < 1024; i++) { 2770 in_port_t prt; 2771 2772 prt = ports[dispatch_uniformrandom( 2773 DISP_ARC4CTX(disp), 2774 nports)]; 2775 isc_sockaddr_setport(&localaddr_bound, prt); 2776 result = open_socket(sockmgr, &localaddr_bound, 2777 0, &sock); 2778 /* 2779 * Continue if the port choosen is already in use 2780 * or the OS has reserved it. 2781 */ 2782 if (result == ISC_R_NOPERM || 2783 result == ISC_R_ADDRINUSE) 2784 continue; 2785 disp->localport = prt; 2786 *sockp = sock; 2787 return (result); 2788 } 2789 2790 /* 2791 * If this fails 1024 times, we then ask the kernel for 2792 * choosing one. 2793 */ 2794 } else { 2795 /* Allow to reuse address for non-random ports. */ 2796 result = open_socket(sockmgr, localaddr, 2797 ISC_SOCKET_REUSEADDRESS, &sock); 2798 2799 if (result == ISC_R_SUCCESS) 2800 *sockp = sock; 2801 2802 return (result); 2803 } 2804 2805 memset(held, 0, sizeof(held)); 2806 i = 0; 2807 2808 for (j = 0; j < 0xffffU; j++) { 2809 result = open_socket(sockmgr, localaddr, 0, &sock); 2810 if (result != ISC_R_SUCCESS) 2811 goto end; 2812 else if (portavailable(mgr, sock, NULL)) 2813 break; 2814 if (held[i] != NULL) 2815 isc_socket_detach(&held[i]); 2816 held[i++] = sock; 2817 sock = NULL; 2818 if (i == DNS_DISPATCH_HELD) 2819 i = 0; 2820 } 2821 if (j == 0xffffU) { 2822 mgr_log(mgr, ISC_LOG_ERROR, 2823 "avoid-v%s-udp-ports: unable to allocate " 2824 "an available port", 2825 isc_sockaddr_pf(localaddr) == AF_INET ? "4" : "6"); 2826 result = ISC_R_FAILURE; 2827 goto end; 2828 } 2829 *sockp = sock; 2830 2831end: 2832 for (i = 0; i < DNS_DISPATCH_HELD; i++) { 2833 if (held[i] != NULL) 2834 isc_socket_detach(&held[i]); 2835 } 2836 2837 return (result); 2838} 2839 2840static isc_result_t 2841dispatch_createudp(dns_dispatchmgr_t *mgr, isc_socketmgr_t *sockmgr, 2842 isc_taskmgr_t *taskmgr, 2843 isc_sockaddr_t *localaddr, 2844 unsigned int maxrequests, 2845 unsigned int attributes, 2846 dns_dispatch_t **dispp) 2847{ 2848 isc_result_t result; 2849 dns_dispatch_t *disp; 2850 isc_socket_t *sock = NULL; 2851 int i = 0; 2852 2853 /* 2854 * dispatch_allocate() checks mgr for us. 2855 */ 2856 disp = NULL; 2857 result = dispatch_allocate(mgr, maxrequests, &disp); 2858 if (result != ISC_R_SUCCESS) 2859 return (result); 2860 2861 if ((attributes & DNS_DISPATCHATTR_EXCLUSIVE) == 0) { 2862 result = get_udpsocket(mgr, disp, sockmgr, localaddr, &sock); 2863 if (result != ISC_R_SUCCESS) 2864 goto deallocate_dispatch; 2865 } else { 2866 isc_sockaddr_t sa_any; 2867 2868 /* 2869 * For dispatches using exclusive sockets with a specific 2870 * source address, we only check if the specified address is 2871 * available on the system. Query sockets will be created later 2872 * on demand. 2873 */ 2874 isc_sockaddr_anyofpf(&sa_any, isc_sockaddr_pf(localaddr)); 2875 if (!isc_sockaddr_eqaddr(&sa_any, localaddr)) { 2876 result = open_socket(sockmgr, localaddr, 0, &sock); 2877 if (sock != NULL) 2878 isc_socket_detach(&sock); 2879 if (result != ISC_R_SUCCESS) 2880 goto deallocate_dispatch; 2881 } 2882 2883 disp->port_table = isc_mem_get(mgr->mctx, 2884 sizeof(disp->port_table[0]) * 2885 DNS_DISPATCH_PORTTABLESIZE); 2886 if (disp->port_table == NULL) 2887 goto deallocate_dispatch; 2888 for (i = 0; i < DNS_DISPATCH_PORTTABLESIZE; i++) 2889 ISC_LIST_INIT(disp->port_table[i]); 2890 2891 result = isc_mempool_create(mgr->mctx, sizeof(dispportentry_t), 2892 &disp->portpool); 2893 if (result != ISC_R_SUCCESS) 2894 goto deallocate_dispatch; 2895 isc_mempool_setname(disp->portpool, "disp_portpool"); 2896 isc_mempool_setfreemax(disp->portpool, 128); 2897 } 2898 disp->socktype = isc_sockettype_udp; 2899 disp->socket = sock; 2900 disp->local = *localaddr; 2901 2902 if ((attributes & DNS_DISPATCHATTR_EXCLUSIVE) != 0) 2903 disp->ntasks = MAX_INTERNAL_TASKS; 2904 else 2905 disp->ntasks = 1; 2906 for (i = 0; i < disp->ntasks; i++) { 2907 disp->task[i] = NULL; 2908 result = isc_task_create(taskmgr, 0, &disp->task[i]); 2909 if (result != ISC_R_SUCCESS) { 2910 while (--i >= 0) { 2911 isc_task_shutdown(disp->task[i]); 2912 isc_task_detach(&disp->task[i]); 2913 } 2914 goto kill_socket; 2915 } 2916 isc_task_setname(disp->task[i], "udpdispatch", disp); 2917 } 2918 2919 disp->ctlevent = isc_event_allocate(mgr->mctx, disp, 2920 DNS_EVENT_DISPATCHCONTROL, 2921 destroy_disp, disp, 2922 sizeof(isc_event_t)); 2923 if (disp->ctlevent == NULL) { 2924 result = ISC_R_NOMEMORY; 2925 goto kill_task; 2926 } 2927 2928 attributes &= ~DNS_DISPATCHATTR_TCP; 2929 attributes |= DNS_DISPATCHATTR_UDP; 2930 disp->attributes = attributes; 2931 2932 /* 2933 * Append it to the dispatcher list. 2934 */ 2935 ISC_LIST_APPEND(mgr->list, disp, link); 2936 2937 mgr_log(mgr, LVL(90), "created UDP dispatcher %p", disp); 2938 dispatch_log(disp, LVL(90), "created task %p", disp->task[0]); /* XXX */ 2939 if (disp->socket != NULL) 2940 dispatch_log(disp, LVL(90), "created socket %p", disp->socket); 2941 2942 *dispp = disp; 2943 return (result); 2944 2945 /* 2946 * Error returns. 2947 */ 2948 kill_task: 2949 for (i = 0; i < disp->ntasks; i++) 2950 isc_task_detach(&disp->task[i]); 2951 kill_socket: 2952 if (disp->socket != NULL) 2953 isc_socket_detach(&disp->socket); 2954 deallocate_dispatch: 2955 dispatch_free(&disp); 2956 2957 return (result); 2958} 2959 2960void 2961dns_dispatch_attach(dns_dispatch_t *disp, dns_dispatch_t **dispp) { 2962 REQUIRE(VALID_DISPATCH(disp)); 2963 REQUIRE(dispp != NULL && *dispp == NULL); 2964 2965 LOCK(&disp->lock); 2966 disp->refcount++; 2967 UNLOCK(&disp->lock); 2968 2969 *dispp = disp; 2970} 2971 2972/* 2973 * It is important to lock the manager while we are deleting the dispatch, 2974 * since dns_dispatch_getudp will call dispatch_find, which returns to 2975 * the caller a dispatch but does not attach to it until later. _getudp 2976 * locks the manager, however, so locking it here will keep us from attaching 2977 * to a dispatcher that is in the process of going away. 2978 */ 2979void 2980dns_dispatch_detach(dns_dispatch_t **dispp) { 2981 dns_dispatch_t *disp; 2982 dispsocket_t *dispsock; 2983 isc_boolean_t killit; 2984 2985 REQUIRE(dispp != NULL && VALID_DISPATCH(*dispp)); 2986 2987 disp = *dispp; 2988 *dispp = NULL; 2989 2990 LOCK(&disp->lock); 2991 2992 INSIST(disp->refcount > 0); 2993 disp->refcount--; 2994 if (disp->refcount == 0) { 2995 if (disp->recv_pending > 0) 2996 isc_socket_cancel(disp->socket, disp->task[0], 2997 ISC_SOCKCANCEL_RECV); 2998 for (dispsock = ISC_LIST_HEAD(disp->activesockets); 2999 dispsock != NULL; 3000 dispsock = ISC_LIST_NEXT(dispsock, link)) { 3001 isc_socket_cancel(dispsock->socket, dispsock->task, 3002 ISC_SOCKCANCEL_RECV); 3003 } 3004 disp->shutting_down = 1; 3005 } 3006 3007 dispatch_log(disp, LVL(90), "detach: refcount %d", disp->refcount); 3008 3009 killit = destroy_disp_ok(disp); 3010 UNLOCK(&disp->lock); 3011 if (killit) 3012 isc_task_send(disp->task[0], &disp->ctlevent); 3013} 3014 3015isc_result_t 3016dns_dispatch_addresponse2(dns_dispatch_t *disp, isc_sockaddr_t *dest, 3017 isc_task_t *task, isc_taskaction_t action, void *arg, 3018 dns_messageid_t *idp, dns_dispentry_t **resp, 3019 isc_socketmgr_t *sockmgr) 3020{ 3021 dns_dispentry_t *res; 3022 unsigned int bucket; 3023 in_port_t localport = 0; 3024 dns_messageid_t id; 3025 int i; 3026 isc_boolean_t ok; 3027 dns_qid_t *qid; 3028 dispsocket_t *dispsocket = NULL; 3029 isc_result_t result; 3030 3031 REQUIRE(VALID_DISPATCH(disp)); 3032 REQUIRE(task != NULL); 3033 REQUIRE(dest != NULL); 3034 REQUIRE(resp != NULL && *resp == NULL); 3035 REQUIRE(idp != NULL); 3036 if ((disp->attributes & DNS_DISPATCHATTR_EXCLUSIVE) != 0) 3037 REQUIRE(sockmgr != NULL); 3038 3039 LOCK(&disp->lock); 3040 3041 if (disp->shutting_down == 1) { 3042 UNLOCK(&disp->lock); 3043 return (ISC_R_SHUTTINGDOWN); 3044 } 3045 3046 if (disp->requests >= disp->maxrequests) { 3047 UNLOCK(&disp->lock); 3048 return (ISC_R_QUOTA); 3049 } 3050 3051 if ((disp->attributes & DNS_DISPATCHATTR_EXCLUSIVE) != 0 && 3052 disp->nsockets > DNS_DISPATCH_SOCKSQUOTA) { 3053 dispsocket_t *oldestsocket; 3054 dns_dispentry_t *oldestresp; 3055 dns_dispatchevent_t *rev; 3056 3057 /* 3058 * Kill oldest outstanding query if the number of sockets 3059 * exceeds the quota to keep the room for new queries. 3060 */ 3061 oldestsocket = ISC_LIST_HEAD(disp->activesockets); 3062 oldestresp = oldestsocket->resp; 3063 if (oldestresp != NULL && !oldestresp->item_out) { 3064 rev = allocate_event(oldestresp->disp); 3065 if (rev != NULL) { 3066 rev->buffer.base = NULL; 3067 rev->result = ISC_R_CANCELED; 3068 rev->id = oldestresp->id; 3069 ISC_EVENT_INIT(rev, sizeof(*rev), 0, 3070 NULL, DNS_EVENT_DISPATCH, 3071 oldestresp->action, 3072 oldestresp->arg, oldestresp, 3073 NULL, NULL); 3074 oldestresp->item_out = ISC_TRUE; 3075 isc_task_send(oldestresp->task, 3076 ISC_EVENT_PTR(&rev)); 3077 inc_stats(disp->mgr, 3078 dns_resstatscounter_dispabort); 3079 } 3080 } 3081 3082 /* 3083 * Move this entry to the tail so that it won't (easily) be 3084 * examined before actually being canceled. 3085 */ 3086 ISC_LIST_UNLINK(disp->activesockets, oldestsocket, link); 3087 ISC_LIST_APPEND(disp->activesockets, oldestsocket, link); 3088 } 3089 3090 qid = DNS_QID(disp); 3091 LOCK(&qid->lock); 3092 3093 if ((disp->attributes & DNS_DISPATCHATTR_EXCLUSIVE) != 0) { 3094 /* 3095 * Get a separate UDP socket with a random port number. 3096 */ 3097 result = get_dispsocket(disp, dest, sockmgr, qid, &dispsocket, 3098 &localport); 3099 if (result != ISC_R_SUCCESS) { 3100 UNLOCK(&qid->lock); 3101 UNLOCK(&disp->lock); 3102 inc_stats(disp->mgr, dns_resstatscounter_dispsockfail); 3103 return (result); 3104 } 3105 } else { 3106 localport = disp->localport; 3107 } 3108 3109 /* 3110 * Try somewhat hard to find an unique ID. 3111 */ 3112 id = (dns_messageid_t)dispatch_random(DISP_ARC4CTX(disp)); 3113 bucket = dns_hash(qid, dest, id, localport); 3114 ok = ISC_FALSE; 3115 for (i = 0; i < 64; i++) { 3116 if (entry_search(qid, dest, id, localport, bucket) == NULL) { 3117 ok = ISC_TRUE; 3118 break; 3119 } 3120 id += qid->qid_increment; 3121 id &= 0x0000ffff; 3122 bucket = dns_hash(qid, dest, id, localport); 3123 } 3124 3125 if (!ok) { 3126 UNLOCK(&qid->lock); 3127 UNLOCK(&disp->lock); 3128 return (ISC_R_NOMORE); 3129 } 3130 3131 res = isc_mempool_get(disp->mgr->rpool); 3132 if (res == NULL) { 3133 UNLOCK(&qid->lock); 3134 UNLOCK(&disp->lock); 3135 if (dispsocket != NULL) 3136 destroy_dispsocket(disp, &dispsocket); 3137 return (ISC_R_NOMEMORY); 3138 } 3139 3140 disp->refcount++; 3141 disp->requests++; 3142 res->task = NULL; 3143 isc_task_attach(task, &res->task); 3144 res->disp = disp; 3145 res->id = id; 3146 res->port = localport; 3147 res->bucket = bucket; 3148 res->host = *dest; 3149 res->action = action; 3150 res->arg = arg; 3151 res->dispsocket = dispsocket; 3152 if (dispsocket != NULL) 3153 dispsocket->resp = res; 3154 res->item_out = ISC_FALSE; 3155 ISC_LIST_INIT(res->items); 3156 ISC_LINK_INIT(res, link); 3157 res->magic = RESPONSE_MAGIC; 3158 ISC_LIST_APPEND(qid->qid_table[bucket], res, link); 3159 UNLOCK(&qid->lock); 3160 3161 request_log(disp, res, LVL(90), 3162 "attached to task %p", res->task); 3163 3164 if (((disp->attributes & DNS_DISPATCHATTR_UDP) != 0) || 3165 ((disp->attributes & DNS_DISPATCHATTR_CONNECTED) != 0)) { 3166 result = startrecv(disp, dispsocket); 3167 if (result != ISC_R_SUCCESS) { 3168 LOCK(&qid->lock); 3169 ISC_LIST_UNLINK(qid->qid_table[bucket], res, link); 3170 UNLOCK(&qid->lock); 3171 3172 if (dispsocket != NULL) 3173 destroy_dispsocket(disp, &dispsocket); 3174 3175 disp->refcount--; 3176 disp->requests--; 3177 3178 UNLOCK(&disp->lock); 3179 isc_task_detach(&res->task); 3180 isc_mempool_put(disp->mgr->rpool, res); 3181 return (result); 3182 } 3183 } 3184 3185 if (dispsocket != NULL) 3186 ISC_LIST_APPEND(disp->activesockets, dispsocket, link); 3187 3188 UNLOCK(&disp->lock); 3189 3190 *idp = id; 3191 *resp = res; 3192 3193 if ((disp->attributes & DNS_DISPATCHATTR_EXCLUSIVE) != 0) 3194 INSIST(res->dispsocket != NULL); 3195 3196 return (ISC_R_SUCCESS); 3197} 3198 3199isc_result_t 3200dns_dispatch_addresponse(dns_dispatch_t *disp, isc_sockaddr_t *dest, 3201 isc_task_t *task, isc_taskaction_t action, void *arg, 3202 dns_messageid_t *idp, dns_dispentry_t **resp) 3203{ 3204 REQUIRE(VALID_DISPATCH(disp)); 3205 REQUIRE((disp->attributes & DNS_DISPATCHATTR_EXCLUSIVE) == 0); 3206 3207 return (dns_dispatch_addresponse2(disp, dest, task, action, arg, 3208 idp, resp, NULL)); 3209} 3210 3211void 3212dns_dispatch_starttcp(dns_dispatch_t *disp) { 3213 3214 REQUIRE(VALID_DISPATCH(disp)); 3215 3216 dispatch_log(disp, LVL(90), "starttcp %p", disp->task[0]); 3217 3218 LOCK(&disp->lock); 3219 disp->attributes |= DNS_DISPATCHATTR_CONNECTED; 3220 (void)startrecv(disp, NULL); 3221 UNLOCK(&disp->lock); 3222} 3223 3224void 3225dns_dispatch_removeresponse(dns_dispentry_t **resp, 3226 dns_dispatchevent_t **sockevent) 3227{ 3228 dns_dispatchmgr_t *mgr; 3229 dns_dispatch_t *disp; 3230 dns_dispentry_t *res; 3231 dispsocket_t *dispsock; 3232 dns_dispatchevent_t *ev; 3233 unsigned int bucket; 3234 isc_boolean_t killit; 3235 unsigned int n; 3236 isc_eventlist_t events; 3237 dns_qid_t *qid; 3238 3239 REQUIRE(resp != NULL); 3240 REQUIRE(VALID_RESPONSE(*resp)); 3241 3242 res = *resp; 3243 *resp = NULL; 3244 3245 disp = res->disp; 3246 REQUIRE(VALID_DISPATCH(disp)); 3247 mgr = disp->mgr; 3248 REQUIRE(VALID_DISPATCHMGR(mgr)); 3249 3250 qid = DNS_QID(disp); 3251 3252 if (sockevent != NULL) { 3253 REQUIRE(*sockevent != NULL); 3254 ev = *sockevent; 3255 *sockevent = NULL; 3256 } else { 3257 ev = NULL; 3258 } 3259 3260 LOCK(&disp->lock); 3261 3262 INSIST(disp->requests > 0); 3263 disp->requests--; 3264 INSIST(disp->refcount > 0); 3265 disp->refcount--; 3266 if (disp->refcount == 0) { 3267 if (disp->recv_pending > 0) 3268 isc_socket_cancel(disp->socket, disp->task[0], 3269 ISC_SOCKCANCEL_RECV); 3270 for (dispsock = ISC_LIST_HEAD(disp->activesockets); 3271 dispsock != NULL; 3272 dispsock = ISC_LIST_NEXT(dispsock, link)) { 3273 isc_socket_cancel(dispsock->socket, dispsock->task, 3274 ISC_SOCKCANCEL_RECV); 3275 } 3276 disp->shutting_down = 1; 3277 } 3278 3279 bucket = res->bucket; 3280 3281 LOCK(&qid->lock); 3282 ISC_LIST_UNLINK(qid->qid_table[bucket], res, link); 3283 UNLOCK(&qid->lock); 3284 3285 if (ev == NULL && res->item_out) { 3286 /* 3287 * We've posted our event, but the caller hasn't gotten it 3288 * yet. Take it back. 3289 */ 3290 ISC_LIST_INIT(events); 3291 n = isc_task_unsend(res->task, res, DNS_EVENT_DISPATCH, 3292 NULL, &events); 3293 /* 3294 * We had better have gotten it back. 3295 */ 3296 INSIST(n == 1); 3297 ev = (dns_dispatchevent_t *)ISC_LIST_HEAD(events); 3298 } 3299 3300 if (ev != NULL) { 3301 REQUIRE(res->item_out == ISC_TRUE); 3302 res->item_out = ISC_FALSE; 3303 if (ev->buffer.base != NULL) 3304 free_buffer(disp, ev->buffer.base, ev->buffer.length); 3305 free_event(disp, ev); 3306 } 3307 3308 request_log(disp, res, LVL(90), "detaching from task %p", res->task); 3309 isc_task_detach(&res->task); 3310 3311 if (res->dispsocket != NULL) { 3312 isc_socket_cancel(res->dispsocket->socket, 3313 res->dispsocket->task, ISC_SOCKCANCEL_RECV); 3314 res->dispsocket->resp = NULL; 3315 } 3316 3317 /* 3318 * Free any buffered requests as well 3319 */ 3320 ev = ISC_LIST_HEAD(res->items); 3321 while (ev != NULL) { 3322 ISC_LIST_UNLINK(res->items, ev, ev_link); 3323 if (ev->buffer.base != NULL) 3324 free_buffer(disp, ev->buffer.base, ev->buffer.length); 3325 free_event(disp, ev); 3326 ev = ISC_LIST_HEAD(res->items); 3327 } 3328 res->magic = 0; 3329 isc_mempool_put(disp->mgr->rpool, res); 3330 if (disp->shutting_down == 1) 3331 do_cancel(disp); 3332 else 3333 (void)startrecv(disp, NULL); 3334 3335 killit = destroy_disp_ok(disp); 3336 UNLOCK(&disp->lock); 3337 if (killit) 3338 isc_task_send(disp->task[0], &disp->ctlevent); 3339} 3340 3341static void 3342do_cancel(dns_dispatch_t *disp) { 3343 dns_dispatchevent_t *ev; 3344 dns_dispentry_t *resp; 3345 dns_qid_t *qid; 3346 3347 if (disp->shutdown_out == 1) 3348 return; 3349 3350 qid = DNS_QID(disp); 3351 3352 /* 3353 * Search for the first response handler without packets outstanding 3354 * unless a specific hander is given. 3355 */ 3356 LOCK(&qid->lock); 3357 for (resp = linear_first(qid); 3358 resp != NULL && resp->item_out; 3359 /* Empty. */) 3360 resp = linear_next(qid, resp); 3361 3362 /* 3363 * No one to send the cancel event to, so nothing to do. 3364 */ 3365 if (resp == NULL) 3366 goto unlock; 3367 3368 /* 3369 * Send the shutdown failsafe event to this resp. 3370 */ 3371 ev = disp->failsafe_ev; 3372 ISC_EVENT_INIT(ev, sizeof(*ev), 0, NULL, DNS_EVENT_DISPATCH, 3373 resp->action, resp->arg, resp, NULL, NULL); 3374 ev->result = disp->shutdown_why; 3375 ev->buffer.base = NULL; 3376 ev->buffer.length = 0; 3377 disp->shutdown_out = 1; 3378 request_log(disp, resp, LVL(10), 3379 "cancel: failsafe event %p -> task %p", 3380 ev, resp->task); 3381 resp->item_out = ISC_TRUE; 3382 isc_task_send(resp->task, ISC_EVENT_PTR(&ev)); 3383 unlock: 3384 UNLOCK(&qid->lock); 3385} 3386 3387isc_socket_t * 3388dns_dispatch_getsocket(dns_dispatch_t *disp) { 3389 REQUIRE(VALID_DISPATCH(disp)); 3390 3391 return (disp->socket); 3392} 3393 3394isc_socket_t * 3395dns_dispatch_getentrysocket(dns_dispentry_t *resp) { 3396 REQUIRE(VALID_RESPONSE(resp)); 3397 3398 if (resp->dispsocket != NULL) 3399 return (resp->dispsocket->socket); 3400 else 3401 return (NULL); 3402} 3403 3404isc_result_t 3405dns_dispatch_getlocaladdress(dns_dispatch_t *disp, isc_sockaddr_t *addrp) { 3406 3407 REQUIRE(VALID_DISPATCH(disp)); 3408 REQUIRE(addrp != NULL); 3409 3410 if (disp->socktype == isc_sockettype_udp) { 3411 *addrp = disp->local; 3412 return (ISC_R_SUCCESS); 3413 } 3414 return (ISC_R_NOTIMPLEMENTED); 3415} 3416 3417void 3418dns_dispatch_cancel(dns_dispatch_t *disp) { 3419 REQUIRE(VALID_DISPATCH(disp)); 3420 3421 LOCK(&disp->lock); 3422 3423 if (disp->shutting_down == 1) { 3424 UNLOCK(&disp->lock); 3425 return; 3426 } 3427 3428 disp->shutdown_why = ISC_R_CANCELED; 3429 disp->shutting_down = 1; 3430 do_cancel(disp); 3431 3432 UNLOCK(&disp->lock); 3433 3434 return; 3435} 3436 3437unsigned int 3438dns_dispatch_getattributes(dns_dispatch_t *disp) { 3439 REQUIRE(VALID_DISPATCH(disp)); 3440 3441 /* 3442 * We don't bother locking disp here; it's the caller's responsibility 3443 * to use only non volatile flags. 3444 */ 3445 return (disp->attributes); 3446} 3447 3448void 3449dns_dispatch_changeattributes(dns_dispatch_t *disp, 3450 unsigned int attributes, unsigned int mask) 3451{ 3452 REQUIRE(VALID_DISPATCH(disp)); 3453 /* Exclusive attribute can only be set on creation */ 3454 REQUIRE((attributes & DNS_DISPATCHATTR_EXCLUSIVE) == 0); 3455 /* Also, a dispatch with randomport specified cannot start listening */ 3456 REQUIRE((disp->attributes & DNS_DISPATCHATTR_EXCLUSIVE) == 0 || 3457 (attributes & DNS_DISPATCHATTR_NOLISTEN) == 0); 3458 3459 /* XXXMLG 3460 * Should check for valid attributes here! 3461 */ 3462 3463 LOCK(&disp->lock); 3464 3465 if ((mask & DNS_DISPATCHATTR_NOLISTEN) != 0) { 3466 if ((disp->attributes & DNS_DISPATCHATTR_NOLISTEN) != 0 && 3467 (attributes & DNS_DISPATCHATTR_NOLISTEN) == 0) { 3468 disp->attributes &= ~DNS_DISPATCHATTR_NOLISTEN; 3469 (void)startrecv(disp, NULL); 3470 } else if ((disp->attributes & DNS_DISPATCHATTR_NOLISTEN) 3471 == 0 && 3472 (attributes & DNS_DISPATCHATTR_NOLISTEN) != 0) { 3473 disp->attributes |= DNS_DISPATCHATTR_NOLISTEN; 3474 if (disp->recv_pending != 0) 3475 isc_socket_cancel(disp->socket, disp->task[0], 3476 ISC_SOCKCANCEL_RECV); 3477 } 3478 } 3479 3480 disp->attributes &= ~mask; 3481 disp->attributes |= (attributes & mask); 3482 UNLOCK(&disp->lock); 3483} 3484 3485void 3486dns_dispatch_importrecv(dns_dispatch_t *disp, isc_event_t *event) { 3487 void *buf; 3488 isc_socketevent_t *sevent, *newsevent; 3489 3490 REQUIRE(VALID_DISPATCH(disp)); 3491 REQUIRE((disp->attributes & DNS_DISPATCHATTR_NOLISTEN) != 0); 3492 REQUIRE(event != NULL); 3493 3494 sevent = (isc_socketevent_t *)event; 3495 3496 INSIST(sevent->n <= disp->mgr->buffersize); 3497 newsevent = (isc_socketevent_t *) 3498 isc_event_allocate(disp->mgr->mctx, NULL, 3499 DNS_EVENT_IMPORTRECVDONE, udp_shrecv, 3500 disp, sizeof(isc_socketevent_t)); 3501 if (newsevent == NULL) 3502 return; 3503 3504 buf = allocate_udp_buffer(disp); 3505 if (buf == NULL) { 3506 isc_event_free(ISC_EVENT_PTR(&newsevent)); 3507 return; 3508 } 3509 memcpy(buf, sevent->region.base, sevent->n); 3510 newsevent->region.base = buf; 3511 newsevent->region.length = disp->mgr->buffersize; 3512 newsevent->n = sevent->n; 3513 newsevent->result = sevent->result; 3514 newsevent->address = sevent->address; 3515 newsevent->timestamp = sevent->timestamp; 3516 newsevent->pktinfo = sevent->pktinfo; 3517 newsevent->attributes = sevent->attributes; 3518 3519 isc_task_send(disp->task[0], ISC_EVENT_PTR(&newsevent)); 3520} 3521 3522#if 0 3523void 3524dns_dispatchmgr_dump(dns_dispatchmgr_t *mgr) { 3525 dns_dispatch_t *disp; 3526 char foo[1024]; 3527 3528 disp = ISC_LIST_HEAD(mgr->list); 3529 while (disp != NULL) { 3530 isc_sockaddr_format(&disp->local, foo, sizeof(foo)); 3531 printf("\tdispatch %p, addr %s\n", disp, foo); 3532 disp = ISC_LIST_NEXT(disp, link); 3533 } 3534} 3535#endif 3536