contrib/unbound/services/mesh.c

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