1 /* 2 * services/mesh.c - deal with mesh of query states and handle events for that. 3 * 4 * Copyright (c) 2007, NLnet Labs. All rights reserved. 5 * 6 * This software is open source. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * Redistributions of source code must retain the above copyright notice, 13 * this list of conditions and the following disclaimer. 14 * 15 * Redistributions in binary form must reproduce the above copyright notice, 16 * this list of conditions and the following disclaimer in the documentation 17 * and/or other materials provided with the distribution. 18 * 19 * Neither the name of the NLNET LABS nor the names of its contributors may 20 * be used to endorse or promote products derived from this software without 21 * specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 27 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36 /** 37 * \file 38 * 39 * This file contains functions to assist in dealing with a mesh of 40 * query states. This mesh is supposed to be thread-specific. 41 * It consists of query states (per qname, qtype, qclass) and connections 42 * between query states and the super and subquery states, and replies to 43 * send back to clients. 44 */ 45 #include "config.h" 46 #include "services/mesh.h" 47 #include "services/outbound_list.h" 48 #include "services/cache/dns.h" 49 #include "util/log.h" 50 #include "util/net_help.h" 51 #include "util/module.h" 52 #include "util/regional.h" 53 #include "util/data/msgencode.h" 54 #include "util/timehist.h" 55 #include "util/fptr_wlist.h" 56 #include "util/alloc.h" 57 #include "util/config_file.h" 58 #include "ldns/sbuffer.h" 59 60 /** subtract timers and the values do not overflow or become negative */ 61 static void 62 timeval_subtract(struct timeval* d, const struct timeval* end, const struct timeval* start) 63 { 64 #ifndef S_SPLINT_S 65 time_t end_usec = end->tv_usec; 66 d->tv_sec = end->tv_sec - start->tv_sec; 67 if(end_usec < start->tv_usec) { 68 end_usec += 1000000; 69 d->tv_sec--; 70 } 71 d->tv_usec = end_usec - start->tv_usec; 72 #endif 73 } 74 75 /** add timers and the values do not overflow or become negative */ 76 static void 77 timeval_add(struct timeval* d, const struct timeval* add) 78 { 79 #ifndef S_SPLINT_S 80 d->tv_sec += add->tv_sec; 81 d->tv_usec += add->tv_usec; 82 if(d->tv_usec > 1000000 ) { 83 d->tv_usec -= 1000000; 84 d->tv_sec++; 85 } 86 #endif 87 } 88 89 /** divide sum of timers to get average */ 90 static void 91 timeval_divide(struct timeval* avg, const struct timeval* sum, size_t d) 92 { 93 #ifndef S_SPLINT_S 94 size_t leftover; 95 if(d == 0) { 96 avg->tv_sec = 0; 97 avg->tv_usec = 0; 98 return; 99 } 100 avg->tv_sec = sum->tv_sec / d; 101 avg->tv_usec = sum->tv_usec / d; 102 /* handle fraction from seconds divide */ 103 leftover = sum->tv_sec - avg->tv_sec*d; 104 avg->tv_usec += (leftover*1000000)/d; 105 #endif 106 } 107 108 /** histogram compare of time values */ 109 static int 110 timeval_smaller(const struct timeval* x, const struct timeval* y) 111 { 112 #ifndef S_SPLINT_S 113 if(x->tv_sec < y->tv_sec) 114 return 1; 115 else if(x->tv_sec == y->tv_sec) { 116 if(x->tv_usec <= y->tv_usec) 117 return 1; 118 else return 0; 119 } 120 else return 0; 121 #endif 122 } 123 124 int 125 mesh_state_compare(const void* ap, const void* bp) 126 { 127 struct mesh_state* a = (struct mesh_state*)ap; 128 struct mesh_state* b = (struct mesh_state*)bp; 129 130 if(a->s.is_priming && !b->s.is_priming) 131 return -1; 132 if(!a->s.is_priming && b->s.is_priming) 133 return 1; 134 135 if((a->s.query_flags&BIT_RD) && !(b->s.query_flags&BIT_RD)) 136 return -1; 137 if(!(a->s.query_flags&BIT_RD) && (b->s.query_flags&BIT_RD)) 138 return 1; 139 140 if((a->s.query_flags&BIT_CD) && !(b->s.query_flags&BIT_CD)) 141 return -1; 142 if(!(a->s.query_flags&BIT_CD) && (b->s.query_flags&BIT_CD)) 143 return 1; 144 145 return query_info_compare(&a->s.qinfo, &b->s.qinfo); 146 } 147 148 int 149 mesh_state_ref_compare(const void* ap, const void* bp) 150 { 151 struct mesh_state_ref* a = (struct mesh_state_ref*)ap; 152 struct mesh_state_ref* b = (struct mesh_state_ref*)bp; 153 return mesh_state_compare(a->s, b->s); 154 } 155 156 struct mesh_area* 157 mesh_create(struct module_stack* stack, struct module_env* env) 158 { 159 struct mesh_area* mesh = calloc(1, sizeof(struct mesh_area)); 160 if(!mesh) { 161 log_err("mesh area alloc: out of memory"); 162 return NULL; 163 } 164 mesh->histogram = timehist_setup(); 165 mesh->qbuf_bak = sldns_buffer_new(env->cfg->msg_buffer_size); 166 if(!mesh->histogram || !mesh->qbuf_bak) { 167 free(mesh); 168 log_err("mesh area alloc: out of memory"); 169 return NULL; 170 } 171 mesh->mods = *stack; 172 mesh->env = env; 173 rbtree_init(&mesh->run, &mesh_state_compare); 174 rbtree_init(&mesh->all, &mesh_state_compare); 175 mesh->num_reply_addrs = 0; 176 mesh->num_reply_states = 0; 177 mesh->num_detached_states = 0; 178 mesh->num_forever_states = 0; 179 mesh->stats_jostled = 0; 180 mesh->stats_dropped = 0; 181 mesh->max_reply_states = env->cfg->num_queries_per_thread; 182 mesh->max_forever_states = (mesh->max_reply_states+1)/2; 183 #ifndef S_SPLINT_S 184 mesh->jostle_max.tv_sec = (time_t)(env->cfg->jostle_time / 1000); 185 mesh->jostle_max.tv_usec = (time_t)((env->cfg->jostle_time % 1000) 186 *1000); 187 #endif 188 return mesh; 189 } 190 191 /** help mesh delete delete mesh states */ 192 static void 193 mesh_delete_helper(rbnode_t* n) 194 { 195 struct mesh_state* mstate = (struct mesh_state*)n->key; 196 /* perform a full delete, not only 'cleanup' routine, 197 * because other callbacks expect a clean state in the mesh. 198 * For 're-entrant' calls */ 199 mesh_state_delete(&mstate->s); 200 /* but because these delete the items from the tree, postorder 201 * traversal and rbtree rebalancing do not work together */ 202 } 203 204 void 205 mesh_delete(struct mesh_area* mesh) 206 { 207 if(!mesh) 208 return; 209 /* free all query states */ 210 while(mesh->all.count) 211 mesh_delete_helper(mesh->all.root); 212 timehist_delete(mesh->histogram); 213 sldns_buffer_free(mesh->qbuf_bak); 214 free(mesh); 215 } 216 217 void 218 mesh_delete_all(struct mesh_area* mesh) 219 { 220 /* free all query states */ 221 while(mesh->all.count) 222 mesh_delete_helper(mesh->all.root); 223 mesh->stats_dropped += mesh->num_reply_addrs; 224 /* clear mesh area references */ 225 rbtree_init(&mesh->run, &mesh_state_compare); 226 rbtree_init(&mesh->all, &mesh_state_compare); 227 mesh->num_reply_addrs = 0; 228 mesh->num_reply_states = 0; 229 mesh->num_detached_states = 0; 230 mesh->num_forever_states = 0; 231 mesh->forever_first = NULL; 232 mesh->forever_last = NULL; 233 mesh->jostle_first = NULL; 234 mesh->jostle_last = NULL; 235 } 236 237 int mesh_make_new_space(struct mesh_area* mesh, sldns_buffer* qbuf) 238 { 239 struct mesh_state* m = mesh->jostle_first; 240 /* free space is available */ 241 if(mesh->num_reply_states < mesh->max_reply_states) 242 return 1; 243 /* try to kick out a jostle-list item */ 244 if(m && m->reply_list && m->list_select == mesh_jostle_list) { 245 /* how old is it? */ 246 struct timeval age; 247 timeval_subtract(&age, mesh->env->now_tv, 248 &m->reply_list->start_time); 249 if(timeval_smaller(&mesh->jostle_max, &age)) { 250 /* its a goner */ 251 log_nametypeclass(VERB_ALGO, "query jostled out to " 252 "make space for a new one", 253 m->s.qinfo.qname, m->s.qinfo.qtype, 254 m->s.qinfo.qclass); 255 /* backup the query */ 256 if(qbuf) sldns_buffer_copy(mesh->qbuf_bak, qbuf); 257 /* notify supers */ 258 if(m->super_set.count > 0) { 259 verbose(VERB_ALGO, "notify supers of failure"); 260 m->s.return_msg = NULL; 261 m->s.return_rcode = LDNS_RCODE_SERVFAIL; 262 mesh_walk_supers(mesh, m); 263 } 264 mesh->stats_jostled ++; 265 mesh_state_delete(&m->s); 266 /* restore the query - note that the qinfo ptr to 267 * the querybuffer is then correct again. */ 268 if(qbuf) sldns_buffer_copy(qbuf, mesh->qbuf_bak); 269 return 1; 270 } 271 } 272 /* no space for new item */ 273 return 0; 274 } 275 276 void mesh_new_client(struct mesh_area* mesh, struct query_info* qinfo, 277 uint16_t qflags, struct edns_data* edns, struct comm_reply* rep, 278 uint16_t qid) 279 { 280 /* do not use CD flag from user for mesh state, we want the CD-query 281 * to receive validation anyway, to protect out cache contents and 282 * avoid bad-data in this cache that a downstream validator cannot 283 * remove from this cache */ 284 struct mesh_state* s = mesh_area_find(mesh, qinfo, qflags&BIT_RD, 0); 285 int was_detached = 0; 286 int was_noreply = 0; 287 int added = 0; 288 /* does this create a new reply state? */ 289 if(!s || s->list_select == mesh_no_list) { 290 if(!mesh_make_new_space(mesh, rep->c->buffer)) { 291 verbose(VERB_ALGO, "Too many queries. dropping " 292 "incoming query."); 293 comm_point_drop_reply(rep); 294 mesh->stats_dropped ++; 295 return; 296 } 297 /* for this new reply state, the reply address is free, 298 * so the limit of reply addresses does not stop reply states*/ 299 } else { 300 /* protect our memory usage from storing reply addresses */ 301 if(mesh->num_reply_addrs > mesh->max_reply_states*16) { 302 verbose(VERB_ALGO, "Too many requests queued. " 303 "dropping incoming query."); 304 mesh->stats_dropped++; 305 comm_point_drop_reply(rep); 306 return; 307 } 308 } 309 /* see if it already exists, if not, create one */ 310 if(!s) { 311 #ifdef UNBOUND_DEBUG 312 struct rbnode_t* n; 313 #endif 314 s = mesh_state_create(mesh->env, qinfo, qflags&BIT_RD, 0); 315 if(!s) { 316 log_err("mesh_state_create: out of memory; SERVFAIL"); 317 error_encode(rep->c->buffer, LDNS_RCODE_SERVFAIL, 318 qinfo, qid, qflags, edns); 319 comm_point_send_reply(rep); 320 return; 321 } 322 #ifdef UNBOUND_DEBUG 323 n = 324 #else 325 (void) 326 #endif 327 rbtree_insert(&mesh->all, &s->node); 328 log_assert(n != NULL); 329 /* set detached (it is now) */ 330 mesh->num_detached_states++; 331 added = 1; 332 } 333 if(!s->reply_list && !s->cb_list && s->super_set.count == 0) 334 was_detached = 1; 335 if(!s->reply_list && !s->cb_list) 336 was_noreply = 1; 337 /* add reply to s */ 338 if(!mesh_state_add_reply(s, edns, rep, qid, qflags, qinfo->qname)) { 339 log_err("mesh_new_client: out of memory; SERVFAIL"); 340 error_encode(rep->c->buffer, LDNS_RCODE_SERVFAIL, 341 qinfo, qid, qflags, edns); 342 comm_point_send_reply(rep); 343 if(added) 344 mesh_state_delete(&s->s); 345 return; 346 } 347 /* update statistics */ 348 if(was_detached) { 349 log_assert(mesh->num_detached_states > 0); 350 mesh->num_detached_states--; 351 } 352 if(was_noreply) { 353 mesh->num_reply_states ++; 354 } 355 mesh->num_reply_addrs++; 356 if(s->list_select == mesh_no_list) { 357 /* move to either the forever or the jostle_list */ 358 if(mesh->num_forever_states < mesh->max_forever_states) { 359 mesh->num_forever_states ++; 360 mesh_list_insert(s, &mesh->forever_first, 361 &mesh->forever_last); 362 s->list_select = mesh_forever_list; 363 } else { 364 mesh_list_insert(s, &mesh->jostle_first, 365 &mesh->jostle_last); 366 s->list_select = mesh_jostle_list; 367 } 368 } 369 if(added) 370 mesh_run(mesh, s, module_event_new, NULL); 371 } 372 373 int 374 mesh_new_callback(struct mesh_area* mesh, struct query_info* qinfo, 375 uint16_t qflags, struct edns_data* edns, sldns_buffer* buf, 376 uint16_t qid, mesh_cb_func_t cb, void* cb_arg) 377 { 378 struct mesh_state* s = mesh_area_find(mesh, qinfo, qflags&BIT_RD, 0); 379 int was_detached = 0; 380 int was_noreply = 0; 381 int added = 0; 382 /* there are no limits on the number of callbacks */ 383 384 /* see if it already exists, if not, create one */ 385 if(!s) { 386 #ifdef UNBOUND_DEBUG 387 struct rbnode_t* n; 388 #endif 389 s = mesh_state_create(mesh->env, qinfo, qflags&BIT_RD, 0); 390 if(!s) { 391 return 0; 392 } 393 #ifdef UNBOUND_DEBUG 394 n = 395 #else 396 (void) 397 #endif 398 rbtree_insert(&mesh->all, &s->node); 399 log_assert(n != NULL); 400 /* set detached (it is now) */ 401 mesh->num_detached_states++; 402 added = 1; 403 } 404 if(!s->reply_list && !s->cb_list && s->super_set.count == 0) 405 was_detached = 1; 406 if(!s->reply_list && !s->cb_list) 407 was_noreply = 1; 408 /* add reply to s */ 409 if(!mesh_state_add_cb(s, edns, buf, cb, cb_arg, qid, qflags)) { 410 if(added) 411 mesh_state_delete(&s->s); 412 return 0; 413 } 414 /* update statistics */ 415 if(was_detached) { 416 log_assert(mesh->num_detached_states > 0); 417 mesh->num_detached_states--; 418 } 419 if(was_noreply) { 420 mesh->num_reply_states ++; 421 } 422 mesh->num_reply_addrs++; 423 if(added) 424 mesh_run(mesh, s, module_event_new, NULL); 425 return 1; 426 } 427 428 void mesh_new_prefetch(struct mesh_area* mesh, struct query_info* qinfo, 429 uint16_t qflags, time_t leeway) 430 { 431 struct mesh_state* s = mesh_area_find(mesh, qinfo, qflags&BIT_RD, 0); 432 #ifdef UNBOUND_DEBUG 433 struct rbnode_t* n; 434 #endif 435 /* already exists, and for a different purpose perhaps. 436 * if mesh_no_list, keep it that way. */ 437 if(s) { 438 /* make it ignore the cache from now on */ 439 if(!s->s.blacklist) 440 sock_list_insert(&s->s.blacklist, NULL, 0, s->s.region); 441 if(s->s.prefetch_leeway < leeway) 442 s->s.prefetch_leeway = leeway; 443 return; 444 } 445 if(!mesh_make_new_space(mesh, NULL)) { 446 verbose(VERB_ALGO, "Too many queries. dropped prefetch."); 447 mesh->stats_dropped ++; 448 return; 449 } 450 s = mesh_state_create(mesh->env, qinfo, qflags&BIT_RD, 0); 451 if(!s) { 452 log_err("prefetch mesh_state_create: out of memory"); 453 return; 454 } 455 #ifdef UNBOUND_DEBUG 456 n = 457 #else 458 (void) 459 #endif 460 rbtree_insert(&mesh->all, &s->node); 461 log_assert(n != NULL); 462 /* set detached (it is now) */ 463 mesh->num_detached_states++; 464 /* make it ignore the cache */ 465 sock_list_insert(&s->s.blacklist, NULL, 0, s->s.region); 466 s->s.prefetch_leeway = leeway; 467 468 if(s->list_select == mesh_no_list) { 469 /* move to either the forever or the jostle_list */ 470 if(mesh->num_forever_states < mesh->max_forever_states) { 471 mesh->num_forever_states ++; 472 mesh_list_insert(s, &mesh->forever_first, 473 &mesh->forever_last); 474 s->list_select = mesh_forever_list; 475 } else { 476 mesh_list_insert(s, &mesh->jostle_first, 477 &mesh->jostle_last); 478 s->list_select = mesh_jostle_list; 479 } 480 } 481 mesh_run(mesh, s, module_event_new, NULL); 482 } 483 484 void mesh_report_reply(struct mesh_area* mesh, struct outbound_entry* e, 485 struct comm_reply* reply, int what) 486 { 487 enum module_ev event = module_event_reply; 488 e->qstate->reply = reply; 489 if(what != NETEVENT_NOERROR) { 490 event = module_event_noreply; 491 if(what == NETEVENT_CAPSFAIL) 492 event = module_event_capsfail; 493 } 494 mesh_run(mesh, e->qstate->mesh_info, event, e); 495 } 496 497 struct mesh_state* 498 mesh_state_create(struct module_env* env, struct query_info* qinfo, 499 uint16_t qflags, int prime) 500 { 501 struct regional* region = alloc_reg_obtain(env->alloc); 502 struct mesh_state* mstate; 503 int i; 504 if(!region) 505 return NULL; 506 mstate = (struct mesh_state*)regional_alloc(region, 507 sizeof(struct mesh_state)); 508 if(!mstate) { 509 alloc_reg_release(env->alloc, region); 510 return NULL; 511 } 512 memset(mstate, 0, sizeof(*mstate)); 513 mstate->node = *RBTREE_NULL; 514 mstate->run_node = *RBTREE_NULL; 515 mstate->node.key = mstate; 516 mstate->run_node.key = mstate; 517 mstate->reply_list = NULL; 518 mstate->list_select = mesh_no_list; 519 mstate->replies_sent = 0; 520 rbtree_init(&mstate->super_set, &mesh_state_ref_compare); 521 rbtree_init(&mstate->sub_set, &mesh_state_ref_compare); 522 mstate->num_activated = 0; 523 /* init module qstate */ 524 mstate->s.qinfo.qtype = qinfo->qtype; 525 mstate->s.qinfo.qclass = qinfo->qclass; 526 mstate->s.qinfo.qname_len = qinfo->qname_len; 527 mstate->s.qinfo.qname = regional_alloc_init(region, qinfo->qname, 528 qinfo->qname_len); 529 if(!mstate->s.qinfo.qname) { 530 alloc_reg_release(env->alloc, region); 531 return NULL; 532 } 533 /* remove all weird bits from qflags */ 534 mstate->s.query_flags = (qflags & (BIT_RD|BIT_CD)); 535 mstate->s.is_priming = prime; 536 mstate->s.reply = NULL; 537 mstate->s.region = region; 538 mstate->s.curmod = 0; 539 mstate->s.return_msg = 0; 540 mstate->s.return_rcode = LDNS_RCODE_NOERROR; 541 mstate->s.env = env; 542 mstate->s.mesh_info = mstate; 543 mstate->s.prefetch_leeway = 0; 544 /* init modules */ 545 for(i=0; i<env->mesh->mods.num; i++) { 546 mstate->s.minfo[i] = NULL; 547 mstate->s.ext_state[i] = module_state_initial; 548 } 549 return mstate; 550 } 551 552 void 553 mesh_state_cleanup(struct mesh_state* mstate) 554 { 555 struct mesh_area* mesh; 556 int i; 557 if(!mstate) 558 return; 559 mesh = mstate->s.env->mesh; 560 /* drop unsent replies */ 561 if(!mstate->replies_sent) { 562 struct mesh_reply* rep; 563 struct mesh_cb* cb; 564 for(rep=mstate->reply_list; rep; rep=rep->next) { 565 comm_point_drop_reply(&rep->query_reply); 566 mesh->num_reply_addrs--; 567 } 568 for(cb=mstate->cb_list; cb; cb=cb->next) { 569 fptr_ok(fptr_whitelist_mesh_cb(cb->cb)); 570 (*cb->cb)(cb->cb_arg, LDNS_RCODE_SERVFAIL, NULL, 571 sec_status_unchecked, NULL); 572 mesh->num_reply_addrs--; 573 } 574 } 575 576 /* de-init modules */ 577 for(i=0; i<mesh->mods.num; i++) { 578 fptr_ok(fptr_whitelist_mod_clear(mesh->mods.mod[i]->clear)); 579 (*mesh->mods.mod[i]->clear)(&mstate->s, i); 580 mstate->s.minfo[i] = NULL; 581 mstate->s.ext_state[i] = module_finished; 582 } 583 alloc_reg_release(mstate->s.env->alloc, mstate->s.region); 584 } 585 586 void 587 mesh_state_delete(struct module_qstate* qstate) 588 { 589 struct mesh_area* mesh; 590 struct mesh_state_ref* super, ref; 591 struct mesh_state* mstate; 592 if(!qstate) 593 return; 594 mstate = qstate->mesh_info; 595 mesh = mstate->s.env->mesh; 596 mesh_detach_subs(&mstate->s); 597 if(mstate->list_select == mesh_forever_list) { 598 mesh->num_forever_states --; 599 mesh_list_remove(mstate, &mesh->forever_first, 600 &mesh->forever_last); 601 } else if(mstate->list_select == mesh_jostle_list) { 602 mesh_list_remove(mstate, &mesh->jostle_first, 603 &mesh->jostle_last); 604 } 605 if(!mstate->reply_list && !mstate->cb_list 606 && mstate->super_set.count == 0) { 607 log_assert(mesh->num_detached_states > 0); 608 mesh->num_detached_states--; 609 } 610 if(mstate->reply_list || mstate->cb_list) { 611 log_assert(mesh->num_reply_states > 0); 612 mesh->num_reply_states--; 613 } 614 ref.node.key = &ref; 615 ref.s = mstate; 616 RBTREE_FOR(super, struct mesh_state_ref*, &mstate->super_set) { 617 (void)rbtree_delete(&super->s->sub_set, &ref); 618 } 619 (void)rbtree_delete(&mesh->run, mstate); 620 (void)rbtree_delete(&mesh->all, mstate); 621 mesh_state_cleanup(mstate); 622 } 623 624 /** helper recursive rbtree find routine */ 625 static int 626 find_in_subsub(struct mesh_state* m, struct mesh_state* tofind, size_t *c) 627 { 628 struct mesh_state_ref* r; 629 if((*c)++ > MESH_MAX_SUBSUB) 630 return 1; 631 RBTREE_FOR(r, struct mesh_state_ref*, &m->sub_set) { 632 if(r->s == tofind || find_in_subsub(r->s, tofind, c)) 633 return 1; 634 } 635 return 0; 636 } 637 638 /** find cycle for already looked up mesh_state */ 639 static int 640 mesh_detect_cycle_found(struct module_qstate* qstate, struct mesh_state* dep_m) 641 { 642 struct mesh_state* cyc_m = qstate->mesh_info; 643 size_t counter = 0; 644 if(!dep_m) 645 return 0; 646 if(dep_m == cyc_m || find_in_subsub(dep_m, cyc_m, &counter)) { 647 if(counter > MESH_MAX_SUBSUB) 648 return 2; 649 return 1; 650 } 651 return 0; 652 } 653 654 void mesh_detach_subs(struct module_qstate* qstate) 655 { 656 struct mesh_area* mesh = qstate->env->mesh; 657 struct mesh_state_ref* ref, lookup; 658 #ifdef UNBOUND_DEBUG 659 struct rbnode_t* n; 660 #endif 661 lookup.node.key = &lookup; 662 lookup.s = qstate->mesh_info; 663 RBTREE_FOR(ref, struct mesh_state_ref*, &qstate->mesh_info->sub_set) { 664 #ifdef UNBOUND_DEBUG 665 n = 666 #else 667 (void) 668 #endif 669 rbtree_delete(&ref->s->super_set, &lookup); 670 log_assert(n != NULL); /* must have been present */ 671 if(!ref->s->reply_list && !ref->s->cb_list 672 && ref->s->super_set.count == 0) { 673 mesh->num_detached_states++; 674 log_assert(mesh->num_detached_states + 675 mesh->num_reply_states <= mesh->all.count); 676 } 677 } 678 rbtree_init(&qstate->mesh_info->sub_set, &mesh_state_ref_compare); 679 } 680 681 int mesh_attach_sub(struct module_qstate* qstate, struct query_info* qinfo, 682 uint16_t qflags, int prime, struct module_qstate** newq) 683 { 684 /* find it, if not, create it */ 685 struct mesh_area* mesh = qstate->env->mesh; 686 struct mesh_state* sub = mesh_area_find(mesh, qinfo, qflags, prime); 687 int was_detached; 688 if(mesh_detect_cycle_found(qstate, sub)) { 689 verbose(VERB_ALGO, "attach failed, cycle detected"); 690 return 0; 691 } 692 if(!sub) { 693 #ifdef UNBOUND_DEBUG 694 struct rbnode_t* n; 695 #endif 696 /* create a new one */ 697 sub = mesh_state_create(qstate->env, qinfo, qflags, prime); 698 if(!sub) { 699 log_err("mesh_attach_sub: out of memory"); 700 return 0; 701 } 702 #ifdef UNBOUND_DEBUG 703 n = 704 #else 705 (void) 706 #endif 707 rbtree_insert(&mesh->all, &sub->node); 708 log_assert(n != NULL); 709 /* set detached (it is now) */ 710 mesh->num_detached_states++; 711 /* set new query state to run */ 712 #ifdef UNBOUND_DEBUG 713 n = 714 #else 715 (void) 716 #endif 717 rbtree_insert(&mesh->run, &sub->run_node); 718 log_assert(n != NULL); 719 *newq = &sub->s; 720 } else 721 *newq = NULL; 722 was_detached = (sub->super_set.count == 0); 723 if(!mesh_state_attachment(qstate->mesh_info, sub)) 724 return 0; 725 /* if it was a duplicate attachment, the count was not zero before */ 726 if(!sub->reply_list && !sub->cb_list && was_detached && 727 sub->super_set.count == 1) { 728 /* it used to be detached, before this one got added */ 729 log_assert(mesh->num_detached_states > 0); 730 mesh->num_detached_states--; 731 } 732 /* *newq will be run when inited after the current module stops */ 733 return 1; 734 } 735 736 int mesh_state_attachment(struct mesh_state* super, struct mesh_state* sub) 737 { 738 #ifdef UNBOUND_DEBUG 739 struct rbnode_t* n; 740 #endif 741 struct mesh_state_ref* subref; /* points to sub, inserted in super */ 742 struct mesh_state_ref* superref; /* points to super, inserted in sub */ 743 if( !(subref = regional_alloc(super->s.region, 744 sizeof(struct mesh_state_ref))) || 745 !(superref = regional_alloc(sub->s.region, 746 sizeof(struct mesh_state_ref))) ) { 747 log_err("mesh_state_attachment: out of memory"); 748 return 0; 749 } 750 superref->node.key = superref; 751 superref->s = super; 752 subref->node.key = subref; 753 subref->s = sub; 754 if(!rbtree_insert(&sub->super_set, &superref->node)) { 755 /* this should not happen, iterator and validator do not 756 * attach subqueries that are identical. */ 757 /* already attached, we are done, nothing todo. 758 * since superref and subref already allocated in region, 759 * we cannot free them */ 760 return 1; 761 } 762 #ifdef UNBOUND_DEBUG 763 n = 764 #else 765 (void) 766 #endif 767 rbtree_insert(&super->sub_set, &subref->node); 768 log_assert(n != NULL); /* we checked above if statement, the reverse 769 administration should not fail now, unless they are out of sync */ 770 return 1; 771 } 772 773 /** 774 * callback results to mesh cb entry 775 * @param m: mesh state to send it for. 776 * @param rcode: if not 0, error code. 777 * @param rep: reply to send (or NULL if rcode is set). 778 * @param r: callback entry 779 */ 780 static void 781 mesh_do_callback(struct mesh_state* m, int rcode, struct reply_info* rep, 782 struct mesh_cb* r) 783 { 784 int secure; 785 char* reason = NULL; 786 /* bogus messages are not made into servfail, sec_status passed 787 * to the callback function */ 788 if(rep && rep->security == sec_status_secure) 789 secure = 1; 790 else secure = 0; 791 if(!rep && rcode == LDNS_RCODE_NOERROR) 792 rcode = LDNS_RCODE_SERVFAIL; 793 if(!rcode && rep->security == sec_status_bogus) { 794 if(!(reason = errinf_to_str(&m->s))) 795 rcode = LDNS_RCODE_SERVFAIL; 796 } 797 /* send the reply */ 798 if(rcode) { 799 fptr_ok(fptr_whitelist_mesh_cb(r->cb)); 800 (*r->cb)(r->cb_arg, rcode, r->buf, sec_status_unchecked, NULL); 801 } else { 802 size_t udp_size = r->edns.udp_size; 803 sldns_buffer_clear(r->buf); 804 r->edns.edns_version = EDNS_ADVERTISED_VERSION; 805 r->edns.udp_size = EDNS_ADVERTISED_SIZE; 806 r->edns.ext_rcode = 0; 807 r->edns.bits &= EDNS_DO; 808 if(!reply_info_answer_encode(&m->s.qinfo, rep, r->qid, 809 r->qflags, r->buf, 0, 1, 810 m->s.env->scratch, udp_size, &r->edns, 811 (int)(r->edns.bits & EDNS_DO), secure)) 812 { 813 fptr_ok(fptr_whitelist_mesh_cb(r->cb)); 814 (*r->cb)(r->cb_arg, LDNS_RCODE_SERVFAIL, r->buf, 815 sec_status_unchecked, NULL); 816 } else { 817 fptr_ok(fptr_whitelist_mesh_cb(r->cb)); 818 (*r->cb)(r->cb_arg, LDNS_RCODE_NOERROR, r->buf, 819 rep->security, reason); 820 } 821 } 822 free(reason); 823 m->s.env->mesh->num_reply_addrs--; 824 } 825 826 /** 827 * Send reply to mesh reply entry 828 * @param m: mesh state to send it for. 829 * @param rcode: if not 0, error code. 830 * @param rep: reply to send (or NULL if rcode is set). 831 * @param r: reply entry 832 * @param prev: previous reply, already has its answer encoded in buffer. 833 */ 834 static void 835 mesh_send_reply(struct mesh_state* m, int rcode, struct reply_info* rep, 836 struct mesh_reply* r, struct mesh_reply* prev) 837 { 838 struct timeval end_time; 839 struct timeval duration; 840 int secure; 841 /* examine security status */ 842 if(m->s.env->need_to_validate && (!(r->qflags&BIT_CD) || 843 m->s.env->cfg->ignore_cd) && rep && 844 rep->security <= sec_status_bogus) { 845 rcode = LDNS_RCODE_SERVFAIL; 846 if(m->s.env->cfg->stat_extended) 847 m->s.env->mesh->ans_bogus++; 848 } 849 if(rep && rep->security == sec_status_secure) 850 secure = 1; 851 else secure = 0; 852 if(!rep && rcode == LDNS_RCODE_NOERROR) 853 rcode = LDNS_RCODE_SERVFAIL; 854 /* send the reply */ 855 if(prev && prev->qflags == r->qflags && 856 prev->edns.edns_present == r->edns.edns_present && 857 prev->edns.bits == r->edns.bits && 858 prev->edns.udp_size == r->edns.udp_size) { 859 /* if the previous reply is identical to this one, fix ID */ 860 if(prev->query_reply.c->buffer != r->query_reply.c->buffer) 861 sldns_buffer_copy(r->query_reply.c->buffer, 862 prev->query_reply.c->buffer); 863 sldns_buffer_write_at(r->query_reply.c->buffer, 0, 864 &r->qid, sizeof(uint16_t)); 865 sldns_buffer_write_at(r->query_reply.c->buffer, 12, 866 r->qname, m->s.qinfo.qname_len); 867 comm_point_send_reply(&r->query_reply); 868 } else if(rcode) { 869 m->s.qinfo.qname = r->qname; 870 error_encode(r->query_reply.c->buffer, rcode, &m->s.qinfo, 871 r->qid, r->qflags, &r->edns); 872 comm_point_send_reply(&r->query_reply); 873 } else { 874 size_t udp_size = r->edns.udp_size; 875 r->edns.edns_version = EDNS_ADVERTISED_VERSION; 876 r->edns.udp_size = EDNS_ADVERTISED_SIZE; 877 r->edns.ext_rcode = 0; 878 r->edns.bits &= EDNS_DO; 879 m->s.qinfo.qname = r->qname; 880 if(!reply_info_answer_encode(&m->s.qinfo, rep, r->qid, 881 r->qflags, r->query_reply.c->buffer, 0, 1, 882 m->s.env->scratch, udp_size, &r->edns, 883 (int)(r->edns.bits & EDNS_DO), secure)) 884 { 885 error_encode(r->query_reply.c->buffer, 886 LDNS_RCODE_SERVFAIL, &m->s.qinfo, r->qid, 887 r->qflags, &r->edns); 888 } 889 comm_point_send_reply(&r->query_reply); 890 } 891 /* account */ 892 m->s.env->mesh->num_reply_addrs--; 893 end_time = *m->s.env->now_tv; 894 timeval_subtract(&duration, &end_time, &r->start_time); 895 verbose(VERB_ALGO, "query took " ARG_LL "d.%6.6d sec", 896 (long long)duration.tv_sec, (int)duration.tv_usec); 897 m->s.env->mesh->replies_sent++; 898 timeval_add(&m->s.env->mesh->replies_sum_wait, &duration); 899 timehist_insert(m->s.env->mesh->histogram, &duration); 900 if(m->s.env->cfg->stat_extended) { 901 uint16_t rc = FLAGS_GET_RCODE(sldns_buffer_read_u16_at(r-> 902 query_reply.c->buffer, 2)); 903 if(secure) m->s.env->mesh->ans_secure++; 904 m->s.env->mesh->ans_rcode[ rc ] ++; 905 if(rc == 0 && LDNS_ANCOUNT(sldns_buffer_begin(r-> 906 query_reply.c->buffer)) == 0) 907 m->s.env->mesh->ans_nodata++; 908 } 909 } 910 911 void mesh_query_done(struct mesh_state* mstate) 912 { 913 struct mesh_reply* r; 914 struct mesh_reply* prev = NULL; 915 struct mesh_cb* c; 916 struct reply_info* rep = (mstate->s.return_msg? 917 mstate->s.return_msg->rep:NULL); 918 for(r = mstate->reply_list; r; r = r->next) { 919 mesh_send_reply(mstate, mstate->s.return_rcode, rep, r, prev); 920 prev = r; 921 } 922 mstate->replies_sent = 1; 923 for(c = mstate->cb_list; c; c = c->next) { 924 mesh_do_callback(mstate, mstate->s.return_rcode, rep, c); 925 } 926 } 927 928 void mesh_walk_supers(struct mesh_area* mesh, struct mesh_state* mstate) 929 { 930 struct mesh_state_ref* ref; 931 RBTREE_FOR(ref, struct mesh_state_ref*, &mstate->super_set) 932 { 933 /* make super runnable */ 934 (void)rbtree_insert(&mesh->run, &ref->s->run_node); 935 /* callback the function to inform super of result */ 936 fptr_ok(fptr_whitelist_mod_inform_super( 937 mesh->mods.mod[ref->s->s.curmod]->inform_super)); 938 (*mesh->mods.mod[ref->s->s.curmod]->inform_super)(&mstate->s, 939 ref->s->s.curmod, &ref->s->s); 940 } 941 } 942 943 struct mesh_state* mesh_area_find(struct mesh_area* mesh, 944 struct query_info* qinfo, uint16_t qflags, int prime) 945 { 946 struct mesh_state key; 947 struct mesh_state* result; 948 949 key.node.key = &key; 950 key.s.is_priming = prime; 951 key.s.qinfo = *qinfo; 952 key.s.query_flags = qflags; 953 954 result = (struct mesh_state*)rbtree_search(&mesh->all, &key); 955 return result; 956 } 957 958 int mesh_state_add_cb(struct mesh_state* s, struct edns_data* edns, 959 sldns_buffer* buf, mesh_cb_func_t cb, void* cb_arg, 960 uint16_t qid, uint16_t qflags) 961 { 962 struct mesh_cb* r = regional_alloc(s->s.region, 963 sizeof(struct mesh_cb)); 964 if(!r) 965 return 0; 966 r->buf = buf; 967 log_assert(fptr_whitelist_mesh_cb(cb)); /* early failure ifmissing*/ 968 r->cb = cb; 969 r->cb_arg = cb_arg; 970 r->edns = *edns; 971 r->qid = qid; 972 r->qflags = qflags; 973 r->next = s->cb_list; 974 s->cb_list = r; 975 return 1; 976 977 } 978 979 int mesh_state_add_reply(struct mesh_state* s, struct edns_data* edns, 980 struct comm_reply* rep, uint16_t qid, uint16_t qflags, uint8_t* qname) 981 { 982 struct mesh_reply* r = regional_alloc(s->s.region, 983 sizeof(struct mesh_reply)); 984 if(!r) 985 return 0; 986 r->query_reply = *rep; 987 r->edns = *edns; 988 r->qid = qid; 989 r->qflags = qflags; 990 r->start_time = *s->s.env->now_tv; 991 r->next = s->reply_list; 992 r->qname = regional_alloc_init(s->s.region, qname, 993 s->s.qinfo.qname_len); 994 if(!r->qname) 995 return 0; 996 s->reply_list = r; 997 return 1; 998 999 } 1000 1001 /** 1002 * Continue processing the mesh state at another module. 1003 * Handles module to modules tranfer of control. 1004 * Handles module finished. 1005 * @param mesh: the mesh area. 1006 * @param mstate: currently active mesh state. 1007 * Deleted if finished, calls _done and _supers to 1008 * send replies to clients and inform other mesh states. 1009 * This in turn may create additional runnable mesh states. 1010 * @param s: state at which the current module exited. 1011 * @param ev: the event sent to the module. 1012 * returned is the event to send to the next module. 1013 * @return true if continue processing at the new module. 1014 * false if not continued processing is needed. 1015 */ 1016 static int 1017 mesh_continue(struct mesh_area* mesh, struct mesh_state* mstate, 1018 enum module_ext_state s, enum module_ev* ev) 1019 { 1020 mstate->num_activated++; 1021 if(mstate->num_activated > MESH_MAX_ACTIVATION) { 1022 /* module is looping. Stop it. */ 1023 log_err("internal error: looping module stopped"); 1024 log_query_info(VERB_QUERY, "pass error for qstate", 1025 &mstate->s.qinfo); 1026 s = module_error; 1027 } 1028 if(s == module_wait_module || s == module_restart_next) { 1029 /* start next module */ 1030 mstate->s.curmod++; 1031 if(mesh->mods.num == mstate->s.curmod) { 1032 log_err("Cannot pass to next module; at last module"); 1033 log_query_info(VERB_QUERY, "pass error for qstate", 1034 &mstate->s.qinfo); 1035 mstate->s.curmod--; 1036 return mesh_continue(mesh, mstate, module_error, ev); 1037 } 1038 if(s == module_restart_next) { 1039 fptr_ok(fptr_whitelist_mod_clear( 1040 mesh->mods.mod[mstate->s.curmod]->clear)); 1041 (*mesh->mods.mod[mstate->s.curmod]->clear) 1042 (&mstate->s, mstate->s.curmod); 1043 mstate->s.minfo[mstate->s.curmod] = NULL; 1044 } 1045 *ev = module_event_pass; 1046 return 1; 1047 } 1048 if(s == module_error && mstate->s.return_rcode == LDNS_RCODE_NOERROR) { 1049 /* error is bad, handle pass back up below */ 1050 mstate->s.return_rcode = LDNS_RCODE_SERVFAIL; 1051 } 1052 if(s == module_error || s == module_finished) { 1053 if(mstate->s.curmod == 0) { 1054 mesh_query_done(mstate); 1055 mesh_walk_supers(mesh, mstate); 1056 mesh_state_delete(&mstate->s); 1057 return 0; 1058 } 1059 /* pass along the locus of control */ 1060 mstate->s.curmod --; 1061 *ev = module_event_moddone; 1062 return 1; 1063 } 1064 return 0; 1065 } 1066 1067 void mesh_run(struct mesh_area* mesh, struct mesh_state* mstate, 1068 enum module_ev ev, struct outbound_entry* e) 1069 { 1070 enum module_ext_state s; 1071 verbose(VERB_ALGO, "mesh_run: start"); 1072 while(mstate) { 1073 /* run the module */ 1074 fptr_ok(fptr_whitelist_mod_operate( 1075 mesh->mods.mod[mstate->s.curmod]->operate)); 1076 (*mesh->mods.mod[mstate->s.curmod]->operate) 1077 (&mstate->s, ev, mstate->s.curmod, e); 1078 1079 /* examine results */ 1080 mstate->s.reply = NULL; 1081 regional_free_all(mstate->s.env->scratch); 1082 s = mstate->s.ext_state[mstate->s.curmod]; 1083 verbose(VERB_ALGO, "mesh_run: %s module exit state is %s", 1084 mesh->mods.mod[mstate->s.curmod]->name, strextstate(s)); 1085 e = NULL; 1086 if(mesh_continue(mesh, mstate, s, &ev)) 1087 continue; 1088 1089 /* run more modules */ 1090 ev = module_event_pass; 1091 if(mesh->run.count > 0) { 1092 /* pop random element off the runnable tree */ 1093 mstate = (struct mesh_state*)mesh->run.root->key; 1094 (void)rbtree_delete(&mesh->run, mstate); 1095 } else mstate = NULL; 1096 } 1097 if(verbosity >= VERB_ALGO) { 1098 mesh_stats(mesh, "mesh_run: end"); 1099 mesh_log_list(mesh); 1100 } 1101 } 1102 1103 void 1104 mesh_log_list(struct mesh_area* mesh) 1105 { 1106 char buf[30]; 1107 struct mesh_state* m; 1108 int num = 0; 1109 RBTREE_FOR(m, struct mesh_state*, &mesh->all) { 1110 snprintf(buf, sizeof(buf), "%d%s%s%s%s%s mod%d %s%s", 1111 num++, (m->s.is_priming)?"p":"", /* prime */ 1112 (m->s.query_flags&BIT_RD)?"RD":"", 1113 (m->s.query_flags&BIT_CD)?"CD":"", 1114 (m->super_set.count==0)?"d":"", /* detached */ 1115 (m->sub_set.count!=0)?"c":"", /* children */ 1116 m->s.curmod, (m->reply_list)?"rep":"", /*hasreply*/ 1117 (m->cb_list)?"cb":"" /* callbacks */ 1118 ); 1119 log_query_info(VERB_ALGO, buf, &m->s.qinfo); 1120 } 1121 } 1122 1123 void 1124 mesh_stats(struct mesh_area* mesh, const char* str) 1125 { 1126 verbose(VERB_DETAIL, "%s %u recursion states (%u with reply, " 1127 "%u detached), %u waiting replies, %u recursion replies " 1128 "sent, %d replies dropped, %d states jostled out", 1129 str, (unsigned)mesh->all.count, 1130 (unsigned)mesh->num_reply_states, 1131 (unsigned)mesh->num_detached_states, 1132 (unsigned)mesh->num_reply_addrs, 1133 (unsigned)mesh->replies_sent, 1134 (unsigned)mesh->stats_dropped, 1135 (unsigned)mesh->stats_jostled); 1136 if(mesh->replies_sent > 0) { 1137 struct timeval avg; 1138 timeval_divide(&avg, &mesh->replies_sum_wait, 1139 mesh->replies_sent); 1140 log_info("average recursion processing time " 1141 ARG_LL "d.%6.6d sec", 1142 (long long)avg.tv_sec, (int)avg.tv_usec); 1143 log_info("histogram of recursion processing times"); 1144 timehist_log(mesh->histogram, "recursions"); 1145 } 1146 } 1147 1148 void 1149 mesh_stats_clear(struct mesh_area* mesh) 1150 { 1151 if(!mesh) 1152 return; 1153 mesh->replies_sent = 0; 1154 mesh->replies_sum_wait.tv_sec = 0; 1155 mesh->replies_sum_wait.tv_usec = 0; 1156 mesh->stats_jostled = 0; 1157 mesh->stats_dropped = 0; 1158 timehist_clear(mesh->histogram); 1159 mesh->ans_secure = 0; 1160 mesh->ans_bogus = 0; 1161 memset(&mesh->ans_rcode[0], 0, sizeof(size_t)*16); 1162 mesh->ans_nodata = 0; 1163 } 1164 1165 size_t 1166 mesh_get_mem(struct mesh_area* mesh) 1167 { 1168 struct mesh_state* m; 1169 size_t s = sizeof(*mesh) + sizeof(struct timehist) + 1170 sizeof(struct th_buck)*mesh->histogram->num + 1171 sizeof(sldns_buffer) + sldns_buffer_capacity(mesh->qbuf_bak); 1172 RBTREE_FOR(m, struct mesh_state*, &mesh->all) { 1173 /* all, including m itself allocated in qstate region */ 1174 s += regional_get_mem(m->s.region); 1175 } 1176 return s; 1177 } 1178 1179 int 1180 mesh_detect_cycle(struct module_qstate* qstate, struct query_info* qinfo, 1181 uint16_t flags, int prime) 1182 { 1183 struct mesh_area* mesh = qstate->env->mesh; 1184 struct mesh_state* dep_m = mesh_area_find(mesh, qinfo, flags, prime); 1185 return mesh_detect_cycle_found(qstate, dep_m); 1186 } 1187 1188 void mesh_list_insert(struct mesh_state* m, struct mesh_state** fp, 1189 struct mesh_state** lp) 1190 { 1191 /* insert as last element */ 1192 m->prev = *lp; 1193 m->next = NULL; 1194 if(*lp) 1195 (*lp)->next = m; 1196 else *fp = m; 1197 *lp = m; 1198 } 1199 1200 void mesh_list_remove(struct mesh_state* m, struct mesh_state** fp, 1201 struct mesh_state** lp) 1202 { 1203 if(m->next) 1204 m->next->prev = m->prev; 1205 else *lp = m->prev; 1206 if(m->prev) 1207 m->prev->next = m->next; 1208 else *fp = m->next; 1209 } 1210