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 "sldns/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.is_valrec && !b->s.is_valrec) 136 return -1; 137 if(!a->s.is_valrec && b->s.is_valrec) 138 return 1; 139 140 if((a->s.query_flags&BIT_RD) && !(b->s.query_flags&BIT_RD)) 141 return -1; 142 if(!(a->s.query_flags&BIT_RD) && (b->s.query_flags&BIT_RD)) 143 return 1; 144 145 if((a->s.query_flags&BIT_CD) && !(b->s.query_flags&BIT_CD)) 146 return -1; 147 if(!(a->s.query_flags&BIT_CD) && (b->s.query_flags&BIT_CD)) 148 return 1; 149 150 return query_info_compare(&a->s.qinfo, &b->s.qinfo); 151 } 152 153 int 154 mesh_state_ref_compare(const void* ap, const void* bp) 155 { 156 struct mesh_state_ref* a = (struct mesh_state_ref*)ap; 157 struct mesh_state_ref* b = (struct mesh_state_ref*)bp; 158 return mesh_state_compare(a->s, b->s); 159 } 160 161 struct mesh_area* 162 mesh_create(struct module_stack* stack, struct module_env* env) 163 { 164 struct mesh_area* mesh = calloc(1, sizeof(struct mesh_area)); 165 if(!mesh) { 166 log_err("mesh area alloc: out of memory"); 167 return NULL; 168 } 169 mesh->histogram = timehist_setup(); 170 mesh->qbuf_bak = sldns_buffer_new(env->cfg->msg_buffer_size); 171 if(!mesh->histogram || !mesh->qbuf_bak) { 172 free(mesh); 173 log_err("mesh area alloc: out of memory"); 174 return NULL; 175 } 176 mesh->mods = *stack; 177 mesh->env = env; 178 rbtree_init(&mesh->run, &mesh_state_compare); 179 rbtree_init(&mesh->all, &mesh_state_compare); 180 mesh->num_reply_addrs = 0; 181 mesh->num_reply_states = 0; 182 mesh->num_detached_states = 0; 183 mesh->num_forever_states = 0; 184 mesh->stats_jostled = 0; 185 mesh->stats_dropped = 0; 186 mesh->max_reply_states = env->cfg->num_queries_per_thread; 187 mesh->max_forever_states = (mesh->max_reply_states+1)/2; 188 #ifndef S_SPLINT_S 189 mesh->jostle_max.tv_sec = (time_t)(env->cfg->jostle_time / 1000); 190 mesh->jostle_max.tv_usec = (time_t)((env->cfg->jostle_time % 1000) 191 *1000); 192 #endif 193 return mesh; 194 } 195 196 /** help mesh delete delete mesh states */ 197 static void 198 mesh_delete_helper(rbnode_t* n) 199 { 200 struct mesh_state* mstate = (struct mesh_state*)n->key; 201 /* perform a full delete, not only 'cleanup' routine, 202 * because other callbacks expect a clean state in the mesh. 203 * For 're-entrant' calls */ 204 mesh_state_delete(&mstate->s); 205 /* but because these delete the items from the tree, postorder 206 * traversal and rbtree rebalancing do not work together */ 207 } 208 209 void 210 mesh_delete(struct mesh_area* mesh) 211 { 212 if(!mesh) 213 return; 214 /* free all query states */ 215 while(mesh->all.count) 216 mesh_delete_helper(mesh->all.root); 217 timehist_delete(mesh->histogram); 218 sldns_buffer_free(mesh->qbuf_bak); 219 free(mesh); 220 } 221 222 void 223 mesh_delete_all(struct mesh_area* mesh) 224 { 225 /* free all query states */ 226 while(mesh->all.count) 227 mesh_delete_helper(mesh->all.root); 228 mesh->stats_dropped += mesh->num_reply_addrs; 229 /* clear mesh area references */ 230 rbtree_init(&mesh->run, &mesh_state_compare); 231 rbtree_init(&mesh->all, &mesh_state_compare); 232 mesh->num_reply_addrs = 0; 233 mesh->num_reply_states = 0; 234 mesh->num_detached_states = 0; 235 mesh->num_forever_states = 0; 236 mesh->forever_first = NULL; 237 mesh->forever_last = NULL; 238 mesh->jostle_first = NULL; 239 mesh->jostle_last = NULL; 240 } 241 242 int mesh_make_new_space(struct mesh_area* mesh, sldns_buffer* qbuf) 243 { 244 struct mesh_state* m = mesh->jostle_first; 245 /* free space is available */ 246 if(mesh->num_reply_states < mesh->max_reply_states) 247 return 1; 248 /* try to kick out a jostle-list item */ 249 if(m && m->reply_list && m->list_select == mesh_jostle_list) { 250 /* how old is it? */ 251 struct timeval age; 252 timeval_subtract(&age, mesh->env->now_tv, 253 &m->reply_list->start_time); 254 if(timeval_smaller(&mesh->jostle_max, &age)) { 255 /* its a goner */ 256 log_nametypeclass(VERB_ALGO, "query jostled out to " 257 "make space for a new one", 258 m->s.qinfo.qname, m->s.qinfo.qtype, 259 m->s.qinfo.qclass); 260 /* backup the query */ 261 if(qbuf) sldns_buffer_copy(mesh->qbuf_bak, qbuf); 262 /* notify supers */ 263 if(m->super_set.count > 0) { 264 verbose(VERB_ALGO, "notify supers of failure"); 265 m->s.return_msg = NULL; 266 m->s.return_rcode = LDNS_RCODE_SERVFAIL; 267 mesh_walk_supers(mesh, m); 268 } 269 mesh->stats_jostled ++; 270 mesh_state_delete(&m->s); 271 /* restore the query - note that the qinfo ptr to 272 * the querybuffer is then correct again. */ 273 if(qbuf) sldns_buffer_copy(qbuf, mesh->qbuf_bak); 274 return 1; 275 } 276 } 277 /* no space for new item */ 278 return 0; 279 } 280 281 void mesh_new_client(struct mesh_area* mesh, struct query_info* qinfo, 282 uint16_t qflags, struct edns_data* edns, struct comm_reply* rep, 283 uint16_t qid) 284 { 285 struct mesh_state* s = mesh_area_find(mesh, qinfo, qflags&(BIT_RD|BIT_CD), 0, 0); 286 int was_detached = 0; 287 int was_noreply = 0; 288 int added = 0; 289 /* does this create a new reply state? */ 290 if(!s || s->list_select == mesh_no_list) { 291 if(!mesh_make_new_space(mesh, rep->c->buffer)) { 292 verbose(VERB_ALGO, "Too many queries. dropping " 293 "incoming query."); 294 comm_point_drop_reply(rep); 295 mesh->stats_dropped ++; 296 return; 297 } 298 /* for this new reply state, the reply address is free, 299 * so the limit of reply addresses does not stop reply states*/ 300 } else { 301 /* protect our memory usage from storing reply addresses */ 302 if(mesh->num_reply_addrs > mesh->max_reply_states*16) { 303 verbose(VERB_ALGO, "Too many requests queued. " 304 "dropping incoming query."); 305 mesh->stats_dropped++; 306 comm_point_drop_reply(rep); 307 return; 308 } 309 } 310 /* see if it already exists, if not, create one */ 311 if(!s) { 312 #ifdef UNBOUND_DEBUG 313 struct rbnode_t* n; 314 #endif 315 s = mesh_state_create(mesh->env, qinfo, qflags&(BIT_RD|BIT_CD), 0, 0); 316 if(!s) { 317 log_err("mesh_state_create: out of memory; SERVFAIL"); 318 if(!edns_opt_inplace_reply(edns, mesh->env->scratch)) 319 edns->opt_list = NULL; 320 error_encode(rep->c->buffer, LDNS_RCODE_SERVFAIL, 321 qinfo, qid, qflags, edns); 322 comm_point_send_reply(rep); 323 return; 324 } 325 #ifdef UNBOUND_DEBUG 326 n = 327 #else 328 (void) 329 #endif 330 rbtree_insert(&mesh->all, &s->node); 331 log_assert(n != NULL); 332 /* set detached (it is now) */ 333 mesh->num_detached_states++; 334 added = 1; 335 } 336 if(!s->reply_list && !s->cb_list && s->super_set.count == 0) 337 was_detached = 1; 338 if(!s->reply_list && !s->cb_list) 339 was_noreply = 1; 340 /* add reply to s */ 341 if(!mesh_state_add_reply(s, edns, rep, qid, qflags, qinfo->qname)) { 342 log_err("mesh_new_client: out of memory; SERVFAIL"); 343 if(!edns_opt_inplace_reply(edns, mesh->env->scratch)) 344 edns->opt_list = NULL; 345 error_encode(rep->c->buffer, LDNS_RCODE_SERVFAIL, 346 qinfo, qid, qflags, edns); 347 comm_point_send_reply(rep); 348 if(added) 349 mesh_state_delete(&s->s); 350 return; 351 } 352 /* update statistics */ 353 if(was_detached) { 354 log_assert(mesh->num_detached_states > 0); 355 mesh->num_detached_states--; 356 } 357 if(was_noreply) { 358 mesh->num_reply_states ++; 359 } 360 mesh->num_reply_addrs++; 361 if(s->list_select == mesh_no_list) { 362 /* move to either the forever or the jostle_list */ 363 if(mesh->num_forever_states < mesh->max_forever_states) { 364 mesh->num_forever_states ++; 365 mesh_list_insert(s, &mesh->forever_first, 366 &mesh->forever_last); 367 s->list_select = mesh_forever_list; 368 } else { 369 mesh_list_insert(s, &mesh->jostle_first, 370 &mesh->jostle_last); 371 s->list_select = mesh_jostle_list; 372 } 373 } 374 if(added) 375 mesh_run(mesh, s, module_event_new, NULL); 376 } 377 378 int 379 mesh_new_callback(struct mesh_area* mesh, struct query_info* qinfo, 380 uint16_t qflags, struct edns_data* edns, sldns_buffer* buf, 381 uint16_t qid, mesh_cb_func_t cb, void* cb_arg) 382 { 383 struct mesh_state* s = mesh_area_find(mesh, qinfo, qflags&(BIT_RD|BIT_CD), 0, 0); 384 int was_detached = 0; 385 int was_noreply = 0; 386 int added = 0; 387 /* there are no limits on the number of callbacks */ 388 389 /* see if it already exists, if not, create one */ 390 if(!s) { 391 #ifdef UNBOUND_DEBUG 392 struct rbnode_t* n; 393 #endif 394 s = mesh_state_create(mesh->env, qinfo, qflags&(BIT_RD|BIT_CD), 0, 0); 395 if(!s) { 396 return 0; 397 } 398 #ifdef UNBOUND_DEBUG 399 n = 400 #else 401 (void) 402 #endif 403 rbtree_insert(&mesh->all, &s->node); 404 log_assert(n != NULL); 405 /* set detached (it is now) */ 406 mesh->num_detached_states++; 407 added = 1; 408 } 409 if(!s->reply_list && !s->cb_list && s->super_set.count == 0) 410 was_detached = 1; 411 if(!s->reply_list && !s->cb_list) 412 was_noreply = 1; 413 /* add reply to s */ 414 if(!mesh_state_add_cb(s, edns, buf, cb, cb_arg, qid, qflags)) { 415 if(added) 416 mesh_state_delete(&s->s); 417 return 0; 418 } 419 /* update statistics */ 420 if(was_detached) { 421 log_assert(mesh->num_detached_states > 0); 422 mesh->num_detached_states--; 423 } 424 if(was_noreply) { 425 mesh->num_reply_states ++; 426 } 427 mesh->num_reply_addrs++; 428 if(added) 429 mesh_run(mesh, s, module_event_new, NULL); 430 return 1; 431 } 432 433 void mesh_new_prefetch(struct mesh_area* mesh, struct query_info* qinfo, 434 uint16_t qflags, time_t leeway) 435 { 436 struct mesh_state* s = mesh_area_find(mesh, qinfo, qflags&(BIT_RD|BIT_CD), 0, 0); 437 #ifdef UNBOUND_DEBUG 438 struct rbnode_t* n; 439 #endif 440 /* already exists, and for a different purpose perhaps. 441 * if mesh_no_list, keep it that way. */ 442 if(s) { 443 /* make it ignore the cache from now on */ 444 if(!s->s.blacklist) 445 sock_list_insert(&s->s.blacklist, NULL, 0, s->s.region); 446 if(s->s.prefetch_leeway < leeway) 447 s->s.prefetch_leeway = leeway; 448 return; 449 } 450 if(!mesh_make_new_space(mesh, NULL)) { 451 verbose(VERB_ALGO, "Too many queries. dropped prefetch."); 452 mesh->stats_dropped ++; 453 return; 454 } 455 s = mesh_state_create(mesh->env, qinfo, qflags&(BIT_RD|BIT_CD), 0, 0); 456 if(!s) { 457 log_err("prefetch mesh_state_create: out of memory"); 458 return; 459 } 460 #ifdef UNBOUND_DEBUG 461 n = 462 #else 463 (void) 464 #endif 465 rbtree_insert(&mesh->all, &s->node); 466 log_assert(n != NULL); 467 /* set detached (it is now) */ 468 mesh->num_detached_states++; 469 /* make it ignore the cache */ 470 sock_list_insert(&s->s.blacklist, NULL, 0, s->s.region); 471 s->s.prefetch_leeway = leeway; 472 473 if(s->list_select == mesh_no_list) { 474 /* move to either the forever or the jostle_list */ 475 if(mesh->num_forever_states < mesh->max_forever_states) { 476 mesh->num_forever_states ++; 477 mesh_list_insert(s, &mesh->forever_first, 478 &mesh->forever_last); 479 s->list_select = mesh_forever_list; 480 } else { 481 mesh_list_insert(s, &mesh->jostle_first, 482 &mesh->jostle_last); 483 s->list_select = mesh_jostle_list; 484 } 485 } 486 mesh_run(mesh, s, module_event_new, NULL); 487 } 488 489 void mesh_report_reply(struct mesh_area* mesh, struct outbound_entry* e, 490 struct comm_reply* reply, int what) 491 { 492 enum module_ev event = module_event_reply; 493 e->qstate->reply = reply; 494 if(what != NETEVENT_NOERROR) { 495 event = module_event_noreply; 496 if(what == NETEVENT_CAPSFAIL) 497 event = module_event_capsfail; 498 } 499 mesh_run(mesh, e->qstate->mesh_info, event, e); 500 } 501 502 struct mesh_state* 503 mesh_state_create(struct module_env* env, struct query_info* qinfo, 504 uint16_t qflags, int prime, int valrec) 505 { 506 struct regional* region = alloc_reg_obtain(env->alloc); 507 struct mesh_state* mstate; 508 int i; 509 if(!region) 510 return NULL; 511 mstate = (struct mesh_state*)regional_alloc(region, 512 sizeof(struct mesh_state)); 513 if(!mstate) { 514 alloc_reg_release(env->alloc, region); 515 return NULL; 516 } 517 memset(mstate, 0, sizeof(*mstate)); 518 mstate->node = *RBTREE_NULL; 519 mstate->run_node = *RBTREE_NULL; 520 mstate->node.key = mstate; 521 mstate->run_node.key = mstate; 522 mstate->reply_list = NULL; 523 mstate->list_select = mesh_no_list; 524 mstate->replies_sent = 0; 525 rbtree_init(&mstate->super_set, &mesh_state_ref_compare); 526 rbtree_init(&mstate->sub_set, &mesh_state_ref_compare); 527 mstate->num_activated = 0; 528 /* init module qstate */ 529 mstate->s.qinfo.qtype = qinfo->qtype; 530 mstate->s.qinfo.qclass = qinfo->qclass; 531 mstate->s.qinfo.qname_len = qinfo->qname_len; 532 mstate->s.qinfo.qname = regional_alloc_init(region, qinfo->qname, 533 qinfo->qname_len); 534 if(!mstate->s.qinfo.qname) { 535 alloc_reg_release(env->alloc, region); 536 return NULL; 537 } 538 /* remove all weird bits from qflags */ 539 mstate->s.query_flags = (qflags & (BIT_RD|BIT_CD)); 540 mstate->s.is_priming = prime; 541 mstate->s.is_valrec = valrec; 542 mstate->s.reply = NULL; 543 mstate->s.region = region; 544 mstate->s.curmod = 0; 545 mstate->s.return_msg = 0; 546 mstate->s.return_rcode = LDNS_RCODE_NOERROR; 547 mstate->s.env = env; 548 mstate->s.mesh_info = mstate; 549 mstate->s.prefetch_leeway = 0; 550 /* init modules */ 551 for(i=0; i<env->mesh->mods.num; i++) { 552 mstate->s.minfo[i] = NULL; 553 mstate->s.ext_state[i] = module_state_initial; 554 } 555 return mstate; 556 } 557 558 void 559 mesh_state_cleanup(struct mesh_state* mstate) 560 { 561 struct mesh_area* mesh; 562 int i; 563 if(!mstate) 564 return; 565 mesh = mstate->s.env->mesh; 566 /* drop unsent replies */ 567 if(!mstate->replies_sent) { 568 struct mesh_reply* rep; 569 struct mesh_cb* cb; 570 for(rep=mstate->reply_list; rep; rep=rep->next) { 571 comm_point_drop_reply(&rep->query_reply); 572 mesh->num_reply_addrs--; 573 } 574 for(cb=mstate->cb_list; cb; cb=cb->next) { 575 fptr_ok(fptr_whitelist_mesh_cb(cb->cb)); 576 (*cb->cb)(cb->cb_arg, LDNS_RCODE_SERVFAIL, NULL, 577 sec_status_unchecked, NULL); 578 mesh->num_reply_addrs--; 579 } 580 } 581 582 /* de-init modules */ 583 for(i=0; i<mesh->mods.num; i++) { 584 fptr_ok(fptr_whitelist_mod_clear(mesh->mods.mod[i]->clear)); 585 (*mesh->mods.mod[i]->clear)(&mstate->s, i); 586 mstate->s.minfo[i] = NULL; 587 mstate->s.ext_state[i] = module_finished; 588 } 589 alloc_reg_release(mstate->s.env->alloc, mstate->s.region); 590 } 591 592 void 593 mesh_state_delete(struct module_qstate* qstate) 594 { 595 struct mesh_area* mesh; 596 struct mesh_state_ref* super, ref; 597 struct mesh_state* mstate; 598 if(!qstate) 599 return; 600 mstate = qstate->mesh_info; 601 mesh = mstate->s.env->mesh; 602 mesh_detach_subs(&mstate->s); 603 if(mstate->list_select == mesh_forever_list) { 604 mesh->num_forever_states --; 605 mesh_list_remove(mstate, &mesh->forever_first, 606 &mesh->forever_last); 607 } else if(mstate->list_select == mesh_jostle_list) { 608 mesh_list_remove(mstate, &mesh->jostle_first, 609 &mesh->jostle_last); 610 } 611 if(!mstate->reply_list && !mstate->cb_list 612 && mstate->super_set.count == 0) { 613 log_assert(mesh->num_detached_states > 0); 614 mesh->num_detached_states--; 615 } 616 if(mstate->reply_list || mstate->cb_list) { 617 log_assert(mesh->num_reply_states > 0); 618 mesh->num_reply_states--; 619 } 620 ref.node.key = &ref; 621 ref.s = mstate; 622 RBTREE_FOR(super, struct mesh_state_ref*, &mstate->super_set) { 623 (void)rbtree_delete(&super->s->sub_set, &ref); 624 } 625 (void)rbtree_delete(&mesh->run, mstate); 626 (void)rbtree_delete(&mesh->all, mstate); 627 mesh_state_cleanup(mstate); 628 } 629 630 /** helper recursive rbtree find routine */ 631 static int 632 find_in_subsub(struct mesh_state* m, struct mesh_state* tofind, size_t *c) 633 { 634 struct mesh_state_ref* r; 635 if((*c)++ > MESH_MAX_SUBSUB) 636 return 1; 637 RBTREE_FOR(r, struct mesh_state_ref*, &m->sub_set) { 638 if(r->s == tofind || find_in_subsub(r->s, tofind, c)) 639 return 1; 640 } 641 return 0; 642 } 643 644 /** find cycle for already looked up mesh_state */ 645 static int 646 mesh_detect_cycle_found(struct module_qstate* qstate, struct mesh_state* dep_m) 647 { 648 struct mesh_state* cyc_m = qstate->mesh_info; 649 size_t counter = 0; 650 if(!dep_m) 651 return 0; 652 if(dep_m == cyc_m || find_in_subsub(dep_m, cyc_m, &counter)) { 653 if(counter > MESH_MAX_SUBSUB) 654 return 2; 655 return 1; 656 } 657 return 0; 658 } 659 660 void mesh_detach_subs(struct module_qstate* qstate) 661 { 662 struct mesh_area* mesh = qstate->env->mesh; 663 struct mesh_state_ref* ref, lookup; 664 #ifdef UNBOUND_DEBUG 665 struct rbnode_t* n; 666 #endif 667 lookup.node.key = &lookup; 668 lookup.s = qstate->mesh_info; 669 RBTREE_FOR(ref, struct mesh_state_ref*, &qstate->mesh_info->sub_set) { 670 #ifdef UNBOUND_DEBUG 671 n = 672 #else 673 (void) 674 #endif 675 rbtree_delete(&ref->s->super_set, &lookup); 676 log_assert(n != NULL); /* must have been present */ 677 if(!ref->s->reply_list && !ref->s->cb_list 678 && ref->s->super_set.count == 0) { 679 mesh->num_detached_states++; 680 log_assert(mesh->num_detached_states + 681 mesh->num_reply_states <= mesh->all.count); 682 } 683 } 684 rbtree_init(&qstate->mesh_info->sub_set, &mesh_state_ref_compare); 685 } 686 687 int mesh_attach_sub(struct module_qstate* qstate, struct query_info* qinfo, 688 uint16_t qflags, int prime, int valrec, struct module_qstate** newq) 689 { 690 /* find it, if not, create it */ 691 struct mesh_area* mesh = qstate->env->mesh; 692 struct mesh_state* sub = mesh_area_find(mesh, qinfo, qflags, prime, 693 valrec); 694 int was_detached; 695 if(mesh_detect_cycle_found(qstate, sub)) { 696 verbose(VERB_ALGO, "attach failed, cycle detected"); 697 return 0; 698 } 699 if(!sub) { 700 #ifdef UNBOUND_DEBUG 701 struct rbnode_t* n; 702 #endif 703 /* create a new one */ 704 sub = mesh_state_create(qstate->env, qinfo, qflags, prime, 705 valrec); 706 if(!sub) { 707 log_err("mesh_attach_sub: out of memory"); 708 return 0; 709 } 710 #ifdef UNBOUND_DEBUG 711 n = 712 #else 713 (void) 714 #endif 715 rbtree_insert(&mesh->all, &sub->node); 716 log_assert(n != NULL); 717 /* set detached (it is now) */ 718 mesh->num_detached_states++; 719 /* set new query state to run */ 720 #ifdef UNBOUND_DEBUG 721 n = 722 #else 723 (void) 724 #endif 725 rbtree_insert(&mesh->run, &sub->run_node); 726 log_assert(n != NULL); 727 *newq = &sub->s; 728 } else 729 *newq = NULL; 730 was_detached = (sub->super_set.count == 0); 731 if(!mesh_state_attachment(qstate->mesh_info, sub)) 732 return 0; 733 /* if it was a duplicate attachment, the count was not zero before */ 734 if(!sub->reply_list && !sub->cb_list && was_detached && 735 sub->super_set.count == 1) { 736 /* it used to be detached, before this one got added */ 737 log_assert(mesh->num_detached_states > 0); 738 mesh->num_detached_states--; 739 } 740 /* *newq will be run when inited after the current module stops */ 741 return 1; 742 } 743 744 int mesh_state_attachment(struct mesh_state* super, struct mesh_state* sub) 745 { 746 #ifdef UNBOUND_DEBUG 747 struct rbnode_t* n; 748 #endif 749 struct mesh_state_ref* subref; /* points to sub, inserted in super */ 750 struct mesh_state_ref* superref; /* points to super, inserted in sub */ 751 if( !(subref = regional_alloc(super->s.region, 752 sizeof(struct mesh_state_ref))) || 753 !(superref = regional_alloc(sub->s.region, 754 sizeof(struct mesh_state_ref))) ) { 755 log_err("mesh_state_attachment: out of memory"); 756 return 0; 757 } 758 superref->node.key = superref; 759 superref->s = super; 760 subref->node.key = subref; 761 subref->s = sub; 762 if(!rbtree_insert(&sub->super_set, &superref->node)) { 763 /* this should not happen, iterator and validator do not 764 * attach subqueries that are identical. */ 765 /* already attached, we are done, nothing todo. 766 * since superref and subref already allocated in region, 767 * we cannot free them */ 768 return 1; 769 } 770 #ifdef UNBOUND_DEBUG 771 n = 772 #else 773 (void) 774 #endif 775 rbtree_insert(&super->sub_set, &subref->node); 776 log_assert(n != NULL); /* we checked above if statement, the reverse 777 administration should not fail now, unless they are out of sync */ 778 return 1; 779 } 780 781 /** 782 * callback results to mesh cb entry 783 * @param m: mesh state to send it for. 784 * @param rcode: if not 0, error code. 785 * @param rep: reply to send (or NULL if rcode is set). 786 * @param r: callback entry 787 */ 788 static void 789 mesh_do_callback(struct mesh_state* m, int rcode, struct reply_info* rep, 790 struct mesh_cb* r) 791 { 792 int secure; 793 char* reason = NULL; 794 /* bogus messages are not made into servfail, sec_status passed 795 * to the callback function */ 796 if(rep && rep->security == sec_status_secure) 797 secure = 1; 798 else secure = 0; 799 if(!rep && rcode == LDNS_RCODE_NOERROR) 800 rcode = LDNS_RCODE_SERVFAIL; 801 if(!rcode && rep->security == sec_status_bogus) { 802 if(!(reason = errinf_to_str(&m->s))) 803 rcode = LDNS_RCODE_SERVFAIL; 804 } 805 /* send the reply */ 806 if(rcode) { 807 fptr_ok(fptr_whitelist_mesh_cb(r->cb)); 808 (*r->cb)(r->cb_arg, rcode, r->buf, sec_status_unchecked, NULL); 809 } else { 810 size_t udp_size = r->edns.udp_size; 811 sldns_buffer_clear(r->buf); 812 r->edns.edns_version = EDNS_ADVERTISED_VERSION; 813 r->edns.udp_size = EDNS_ADVERTISED_SIZE; 814 r->edns.ext_rcode = 0; 815 r->edns.bits &= EDNS_DO; 816 if(!edns_opt_inplace_reply(&r->edns, m->s.region) || 817 !reply_info_answer_encode(&m->s.qinfo, rep, r->qid, 818 r->qflags, r->buf, 0, 1, 819 m->s.env->scratch, udp_size, &r->edns, 820 (int)(r->edns.bits & EDNS_DO), secure)) 821 { 822 fptr_ok(fptr_whitelist_mesh_cb(r->cb)); 823 (*r->cb)(r->cb_arg, LDNS_RCODE_SERVFAIL, r->buf, 824 sec_status_unchecked, NULL); 825 } else { 826 fptr_ok(fptr_whitelist_mesh_cb(r->cb)); 827 (*r->cb)(r->cb_arg, LDNS_RCODE_NOERROR, r->buf, 828 rep->security, reason); 829 } 830 } 831 free(reason); 832 m->s.env->mesh->num_reply_addrs--; 833 } 834 835 /** 836 * Send reply to mesh reply entry 837 * @param m: mesh state to send it for. 838 * @param rcode: if not 0, error code. 839 * @param rep: reply to send (or NULL if rcode is set). 840 * @param r: reply entry 841 * @param prev: previous reply, already has its answer encoded in buffer. 842 */ 843 static void 844 mesh_send_reply(struct mesh_state* m, int rcode, struct reply_info* rep, 845 struct mesh_reply* r, struct mesh_reply* prev) 846 { 847 struct timeval end_time; 848 struct timeval duration; 849 int secure; 850 /* examine security status */ 851 if(m->s.env->need_to_validate && (!(r->qflags&BIT_CD) || 852 m->s.env->cfg->ignore_cd) && rep && 853 rep->security <= sec_status_bogus) { 854 rcode = LDNS_RCODE_SERVFAIL; 855 if(m->s.env->cfg->stat_extended) 856 m->s.env->mesh->ans_bogus++; 857 } 858 if(rep && rep->security == sec_status_secure) 859 secure = 1; 860 else secure = 0; 861 if(!rep && rcode == LDNS_RCODE_NOERROR) 862 rcode = LDNS_RCODE_SERVFAIL; 863 /* send the reply */ 864 if(prev && prev->qflags == r->qflags && 865 prev->edns.edns_present == r->edns.edns_present && 866 prev->edns.bits == r->edns.bits && 867 prev->edns.udp_size == r->edns.udp_size && 868 edns_opt_list_compare(prev->edns.opt_list, r->edns.opt_list) 869 == 0) { 870 /* if the previous reply is identical to this one, fix ID */ 871 if(prev->query_reply.c->buffer != r->query_reply.c->buffer) 872 sldns_buffer_copy(r->query_reply.c->buffer, 873 prev->query_reply.c->buffer); 874 sldns_buffer_write_at(r->query_reply.c->buffer, 0, 875 &r->qid, sizeof(uint16_t)); 876 sldns_buffer_write_at(r->query_reply.c->buffer, 12, 877 r->qname, m->s.qinfo.qname_len); 878 comm_point_send_reply(&r->query_reply); 879 } else if(rcode) { 880 m->s.qinfo.qname = r->qname; 881 error_encode(r->query_reply.c->buffer, rcode, &m->s.qinfo, 882 r->qid, r->qflags, &r->edns); 883 comm_point_send_reply(&r->query_reply); 884 } else { 885 size_t udp_size = r->edns.udp_size; 886 r->edns.edns_version = EDNS_ADVERTISED_VERSION; 887 r->edns.udp_size = EDNS_ADVERTISED_SIZE; 888 r->edns.ext_rcode = 0; 889 r->edns.bits &= EDNS_DO; 890 m->s.qinfo.qname = r->qname; 891 if(!edns_opt_inplace_reply(&r->edns, m->s.region) || 892 !reply_info_answer_encode(&m->s.qinfo, rep, r->qid, 893 r->qflags, r->query_reply.c->buffer, 0, 1, 894 m->s.env->scratch, udp_size, &r->edns, 895 (int)(r->edns.bits & EDNS_DO), secure)) 896 { 897 error_encode(r->query_reply.c->buffer, 898 LDNS_RCODE_SERVFAIL, &m->s.qinfo, r->qid, 899 r->qflags, &r->edns); 900 } 901 comm_point_send_reply(&r->query_reply); 902 } 903 /* account */ 904 m->s.env->mesh->num_reply_addrs--; 905 end_time = *m->s.env->now_tv; 906 timeval_subtract(&duration, &end_time, &r->start_time); 907 verbose(VERB_ALGO, "query took " ARG_LL "d.%6.6d sec", 908 (long long)duration.tv_sec, (int)duration.tv_usec); 909 m->s.env->mesh->replies_sent++; 910 timeval_add(&m->s.env->mesh->replies_sum_wait, &duration); 911 timehist_insert(m->s.env->mesh->histogram, &duration); 912 if(m->s.env->cfg->stat_extended) { 913 uint16_t rc = FLAGS_GET_RCODE(sldns_buffer_read_u16_at(r-> 914 query_reply.c->buffer, 2)); 915 if(secure) m->s.env->mesh->ans_secure++; 916 m->s.env->mesh->ans_rcode[ rc ] ++; 917 if(rc == 0 && LDNS_ANCOUNT(sldns_buffer_begin(r-> 918 query_reply.c->buffer)) == 0) 919 m->s.env->mesh->ans_nodata++; 920 } 921 } 922 923 void mesh_query_done(struct mesh_state* mstate) 924 { 925 struct mesh_reply* r; 926 struct mesh_reply* prev = NULL; 927 struct mesh_cb* c; 928 struct reply_info* rep = (mstate->s.return_msg? 929 mstate->s.return_msg->rep:NULL); 930 for(r = mstate->reply_list; r; r = r->next) { 931 mesh_send_reply(mstate, mstate->s.return_rcode, rep, r, prev); 932 prev = r; 933 } 934 mstate->replies_sent = 1; 935 for(c = mstate->cb_list; c; c = c->next) { 936 mesh_do_callback(mstate, mstate->s.return_rcode, rep, c); 937 } 938 } 939 940 void mesh_walk_supers(struct mesh_area* mesh, struct mesh_state* mstate) 941 { 942 struct mesh_state_ref* ref; 943 RBTREE_FOR(ref, struct mesh_state_ref*, &mstate->super_set) 944 { 945 /* make super runnable */ 946 (void)rbtree_insert(&mesh->run, &ref->s->run_node); 947 /* callback the function to inform super of result */ 948 fptr_ok(fptr_whitelist_mod_inform_super( 949 mesh->mods.mod[ref->s->s.curmod]->inform_super)); 950 (*mesh->mods.mod[ref->s->s.curmod]->inform_super)(&mstate->s, 951 ref->s->s.curmod, &ref->s->s); 952 } 953 } 954 955 struct mesh_state* mesh_area_find(struct mesh_area* mesh, 956 struct query_info* qinfo, uint16_t qflags, int prime, int valrec) 957 { 958 struct mesh_state key; 959 struct mesh_state* result; 960 961 key.node.key = &key; 962 key.s.is_priming = prime; 963 key.s.is_valrec = valrec; 964 key.s.qinfo = *qinfo; 965 key.s.query_flags = qflags; 966 967 result = (struct mesh_state*)rbtree_search(&mesh->all, &key); 968 return result; 969 } 970 971 int mesh_state_add_cb(struct mesh_state* s, struct edns_data* edns, 972 sldns_buffer* buf, mesh_cb_func_t cb, void* cb_arg, 973 uint16_t qid, uint16_t qflags) 974 { 975 struct mesh_cb* r = regional_alloc(s->s.region, 976 sizeof(struct mesh_cb)); 977 if(!r) 978 return 0; 979 r->buf = buf; 980 log_assert(fptr_whitelist_mesh_cb(cb)); /* early failure ifmissing*/ 981 r->cb = cb; 982 r->cb_arg = cb_arg; 983 r->edns = *edns; 984 if(edns->opt_list) { 985 r->edns.opt_list = edns_opt_copy_region(edns->opt_list, 986 s->s.region); 987 if(!r->edns.opt_list) 988 return 0; 989 } 990 r->qid = qid; 991 r->qflags = qflags; 992 r->next = s->cb_list; 993 s->cb_list = r; 994 return 1; 995 996 } 997 998 int mesh_state_add_reply(struct mesh_state* s, struct edns_data* edns, 999 struct comm_reply* rep, uint16_t qid, uint16_t qflags, uint8_t* qname) 1000 { 1001 struct mesh_reply* r = regional_alloc(s->s.region, 1002 sizeof(struct mesh_reply)); 1003 if(!r) 1004 return 0; 1005 r->query_reply = *rep; 1006 r->edns = *edns; 1007 if(edns->opt_list) { 1008 r->edns.opt_list = edns_opt_copy_region(edns->opt_list, 1009 s->s.region); 1010 if(!r->edns.opt_list) 1011 return 0; 1012 } 1013 r->qid = qid; 1014 r->qflags = qflags; 1015 r->start_time = *s->s.env->now_tv; 1016 r->next = s->reply_list; 1017 r->qname = regional_alloc_init(s->s.region, qname, 1018 s->s.qinfo.qname_len); 1019 if(!r->qname) 1020 return 0; 1021 s->reply_list = r; 1022 return 1; 1023 } 1024 1025 /** 1026 * Continue processing the mesh state at another module. 1027 * Handles module to modules tranfer of control. 1028 * Handles module finished. 1029 * @param mesh: the mesh area. 1030 * @param mstate: currently active mesh state. 1031 * Deleted if finished, calls _done and _supers to 1032 * send replies to clients and inform other mesh states. 1033 * This in turn may create additional runnable mesh states. 1034 * @param s: state at which the current module exited. 1035 * @param ev: the event sent to the module. 1036 * returned is the event to send to the next module. 1037 * @return true if continue processing at the new module. 1038 * false if not continued processing is needed. 1039 */ 1040 static int 1041 mesh_continue(struct mesh_area* mesh, struct mesh_state* mstate, 1042 enum module_ext_state s, enum module_ev* ev) 1043 { 1044 mstate->num_activated++; 1045 if(mstate->num_activated > MESH_MAX_ACTIVATION) { 1046 /* module is looping. Stop it. */ 1047 log_err("internal error: looping module stopped"); 1048 log_query_info(VERB_QUERY, "pass error for qstate", 1049 &mstate->s.qinfo); 1050 s = module_error; 1051 } 1052 if(s == module_wait_module || s == module_restart_next) { 1053 /* start next module */ 1054 mstate->s.curmod++; 1055 if(mesh->mods.num == mstate->s.curmod) { 1056 log_err("Cannot pass to next module; at last module"); 1057 log_query_info(VERB_QUERY, "pass error for qstate", 1058 &mstate->s.qinfo); 1059 mstate->s.curmod--; 1060 return mesh_continue(mesh, mstate, module_error, ev); 1061 } 1062 if(s == module_restart_next) { 1063 fptr_ok(fptr_whitelist_mod_clear( 1064 mesh->mods.mod[mstate->s.curmod]->clear)); 1065 (*mesh->mods.mod[mstate->s.curmod]->clear) 1066 (&mstate->s, mstate->s.curmod); 1067 mstate->s.minfo[mstate->s.curmod] = NULL; 1068 } 1069 *ev = module_event_pass; 1070 return 1; 1071 } 1072 if(s == module_wait_subquery && mstate->sub_set.count == 0) { 1073 log_err("module cannot wait for subquery, subquery list empty"); 1074 log_query_info(VERB_QUERY, "pass error for qstate", 1075 &mstate->s.qinfo); 1076 s = module_error; 1077 } 1078 if(s == module_error && mstate->s.return_rcode == LDNS_RCODE_NOERROR) { 1079 /* error is bad, handle pass back up below */ 1080 mstate->s.return_rcode = LDNS_RCODE_SERVFAIL; 1081 } 1082 if(s == module_error || s == module_finished) { 1083 if(mstate->s.curmod == 0) { 1084 mesh_query_done(mstate); 1085 mesh_walk_supers(mesh, mstate); 1086 mesh_state_delete(&mstate->s); 1087 return 0; 1088 } 1089 /* pass along the locus of control */ 1090 mstate->s.curmod --; 1091 *ev = module_event_moddone; 1092 return 1; 1093 } 1094 return 0; 1095 } 1096 1097 void mesh_run(struct mesh_area* mesh, struct mesh_state* mstate, 1098 enum module_ev ev, struct outbound_entry* e) 1099 { 1100 enum module_ext_state s; 1101 verbose(VERB_ALGO, "mesh_run: start"); 1102 while(mstate) { 1103 /* run the module */ 1104 fptr_ok(fptr_whitelist_mod_operate( 1105 mesh->mods.mod[mstate->s.curmod]->operate)); 1106 (*mesh->mods.mod[mstate->s.curmod]->operate) 1107 (&mstate->s, ev, mstate->s.curmod, e); 1108 1109 /* examine results */ 1110 mstate->s.reply = NULL; 1111 regional_free_all(mstate->s.env->scratch); 1112 s = mstate->s.ext_state[mstate->s.curmod]; 1113 verbose(VERB_ALGO, "mesh_run: %s module exit state is %s", 1114 mesh->mods.mod[mstate->s.curmod]->name, strextstate(s)); 1115 e = NULL; 1116 if(mesh_continue(mesh, mstate, s, &ev)) 1117 continue; 1118 1119 /* run more modules */ 1120 ev = module_event_pass; 1121 if(mesh->run.count > 0) { 1122 /* pop random element off the runnable tree */ 1123 mstate = (struct mesh_state*)mesh->run.root->key; 1124 (void)rbtree_delete(&mesh->run, mstate); 1125 } else mstate = NULL; 1126 } 1127 if(verbosity >= VERB_ALGO) { 1128 mesh_stats(mesh, "mesh_run: end"); 1129 mesh_log_list(mesh); 1130 } 1131 } 1132 1133 void 1134 mesh_log_list(struct mesh_area* mesh) 1135 { 1136 char buf[30]; 1137 struct mesh_state* m; 1138 int num = 0; 1139 RBTREE_FOR(m, struct mesh_state*, &mesh->all) { 1140 snprintf(buf, sizeof(buf), "%d%s%s%s%s%s%s mod%d %s%s", 1141 num++, (m->s.is_priming)?"p":"", /* prime */ 1142 (m->s.is_valrec)?"v":"", /* prime */ 1143 (m->s.query_flags&BIT_RD)?"RD":"", 1144 (m->s.query_flags&BIT_CD)?"CD":"", 1145 (m->super_set.count==0)?"d":"", /* detached */ 1146 (m->sub_set.count!=0)?"c":"", /* children */ 1147 m->s.curmod, (m->reply_list)?"rep":"", /*hasreply*/ 1148 (m->cb_list)?"cb":"" /* callbacks */ 1149 ); 1150 log_query_info(VERB_ALGO, buf, &m->s.qinfo); 1151 } 1152 } 1153 1154 void 1155 mesh_stats(struct mesh_area* mesh, const char* str) 1156 { 1157 verbose(VERB_DETAIL, "%s %u recursion states (%u with reply, " 1158 "%u detached), %u waiting replies, %u recursion replies " 1159 "sent, %d replies dropped, %d states jostled out", 1160 str, (unsigned)mesh->all.count, 1161 (unsigned)mesh->num_reply_states, 1162 (unsigned)mesh->num_detached_states, 1163 (unsigned)mesh->num_reply_addrs, 1164 (unsigned)mesh->replies_sent, 1165 (unsigned)mesh->stats_dropped, 1166 (unsigned)mesh->stats_jostled); 1167 if(mesh->replies_sent > 0) { 1168 struct timeval avg; 1169 timeval_divide(&avg, &mesh->replies_sum_wait, 1170 mesh->replies_sent); 1171 log_info("average recursion processing time " 1172 ARG_LL "d.%6.6d sec", 1173 (long long)avg.tv_sec, (int)avg.tv_usec); 1174 log_info("histogram of recursion processing times"); 1175 timehist_log(mesh->histogram, "recursions"); 1176 } 1177 } 1178 1179 void 1180 mesh_stats_clear(struct mesh_area* mesh) 1181 { 1182 if(!mesh) 1183 return; 1184 mesh->replies_sent = 0; 1185 mesh->replies_sum_wait.tv_sec = 0; 1186 mesh->replies_sum_wait.tv_usec = 0; 1187 mesh->stats_jostled = 0; 1188 mesh->stats_dropped = 0; 1189 timehist_clear(mesh->histogram); 1190 mesh->ans_secure = 0; 1191 mesh->ans_bogus = 0; 1192 memset(&mesh->ans_rcode[0], 0, sizeof(size_t)*16); 1193 mesh->ans_nodata = 0; 1194 } 1195 1196 size_t 1197 mesh_get_mem(struct mesh_area* mesh) 1198 { 1199 struct mesh_state* m; 1200 size_t s = sizeof(*mesh) + sizeof(struct timehist) + 1201 sizeof(struct th_buck)*mesh->histogram->num + 1202 sizeof(sldns_buffer) + sldns_buffer_capacity(mesh->qbuf_bak); 1203 RBTREE_FOR(m, struct mesh_state*, &mesh->all) { 1204 /* all, including m itself allocated in qstate region */ 1205 s += regional_get_mem(m->s.region); 1206 } 1207 return s; 1208 } 1209 1210 int 1211 mesh_detect_cycle(struct module_qstate* qstate, struct query_info* qinfo, 1212 uint16_t flags, int prime, int valrec) 1213 { 1214 struct mesh_area* mesh = qstate->env->mesh; 1215 struct mesh_state* dep_m = mesh_area_find(mesh, qinfo, flags, prime, 1216 valrec); 1217 return mesh_detect_cycle_found(qstate, dep_m); 1218 } 1219 1220 void mesh_list_insert(struct mesh_state* m, struct mesh_state** fp, 1221 struct mesh_state** lp) 1222 { 1223 /* insert as last element */ 1224 m->prev = *lp; 1225 m->next = NULL; 1226 if(*lp) 1227 (*lp)->next = m; 1228 else *fp = m; 1229 *lp = m; 1230 } 1231 1232 void mesh_list_remove(struct mesh_state* m, struct mesh_state** fp, 1233 struct mesh_state** lp) 1234 { 1235 if(m->next) 1236 m->next->prev = m->prev; 1237 else *lp = m->prev; 1238 if(m->prev) 1239 m->prev->next = m->next; 1240 else *fp = m->next; 1241 } 1242