net/tipc/name_table.c

   1 /*
   2  * net/tipc/name_table.c: TIPC name table code
   3  *
   4  * Copyright (c) 2000-2006, 2014-2018, Ericsson AB
   5  * Copyright (c) 2004-2008, 2010-2014, Wind River Systems
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the names of the copyright holders nor the names of its
  17  *    contributors may be used to endorse or promote products derived from
  18  *    this software without specific prior written permission.
  19  *
  20  * Alternatively, this software may be distributed under the terms of the
  21  * GNU General Public License ("GPL") version 2 as published by the Free
  22  * Software Foundation.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  25  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  28  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  29  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  30  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  31  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  32  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  33  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  34  * POSSIBILITY OF SUCH DAMAGE.
  35  */
  36
  37 #include <net/sock.h>
  38 #include "core.h"
  39 #include "netlink.h"
  40 #include "name_table.h"
  41 #include "name_distr.h"
  42 #include "subscr.h"
  43 #include "bcast.h"
  44 #include "addr.h"
  45 #include "node.h"
  46 #include "group.h"
  47
  48 /**
  49  * struct service_range - container for all bindings of a service range
  50  * @lower: service range lower bound
  51  * @upper: service range upper bound
  52  * @tree_node: member of service range RB tree
  53  * @local_publ: list of identical publications made from this node
  54  *   Used by closest_first lookup and multicast lookup algorithm
  55  * @all_publ: all publications identical to this one, whatever node and scope
  56  *   Used by round-robin lookup algorithm
  57  */
  58 struct service_range {
  59         u32 lower;
  60         u32 upper;
  61         struct rb_node tree_node;
  62         struct list_head local_publ;
  63         struct list_head all_publ;
  64 };
  65
  66 /**
  67  * struct tipc_service - container for all published instances of a service type
  68  * @type: 32 bit 'type' value for service
  69  * @ranges: rb tree containing all service ranges for this service
  70  * @service_list: links to adjacent name ranges in hash chain
  71  * @subscriptions: list of subscriptions for this service type
  72  * @lock: spinlock controlling access to pertaining service ranges/publications
  73  * @rcu: RCU callback head used for deferred freeing
  74  */
  75 struct tipc_service {
  76         u32 type;
  77         struct rb_root ranges;
  78         struct hlist_node service_list;
  79         struct list_head subscriptions;
  80         spinlock_t lock; /* Covers service range list */
  81         struct rcu_head rcu;
  82 };
  83
  84 static int hash(int x)
  85 {
  86         return x & (TIPC_NAMETBL_SIZE - 1);
  87 }
  88
  89 /**
  90  * tipc_publ_create - create a publication structure
  91  */
  92 static struct publication *tipc_publ_create(u32 type, u32 lower, u32 upper,
  93                                             u32 scope, u32 node, u32 port,
  94                                             u32 key)
  95 {
  96         struct publication *publ = kzalloc(sizeof(*publ), GFP_ATOMIC);
  97
  98         if (!publ)
  99                 return NULL;
 100
 101         publ->type = type;
 102         publ->lower = lower;
 103         publ->upper = upper;
 104         publ->scope = scope;
 105         publ->node = node;
 106         publ->port = port;
 107         publ->key = key;
 108         INIT_LIST_HEAD(&publ->binding_sock);
 109         INIT_LIST_HEAD(&publ->binding_node);
 110         INIT_LIST_HEAD(&publ->local_publ);
 111         INIT_LIST_HEAD(&publ->all_publ);
 112         return publ;
 113 }
 114
 115 /**
 116  * tipc_service_create - create a service structure for the specified 'type'
 117  *
 118  * Allocates a single range structure and sets it to all 0's.
 119  */
 120 static struct tipc_service *tipc_service_create(u32 type, struct hlist_head *hd)
 121 {
 122         struct tipc_service *service = kzalloc(sizeof(*service), GFP_ATOMIC);
 123
 124         if (!service) {
 125                 pr_warn("Service creation failed, no memory\n");
 126                 return NULL;
 127         }
 128
 129         spin_lock_init(&service->lock);
 130         service->type = type;
 131         service->ranges = RB_ROOT;
 132         INIT_HLIST_NODE(&service->service_list);
 133         INIT_LIST_HEAD(&service->subscriptions);
 134         hlist_add_head_rcu(&service->service_list, hd);
 135         return service;
 136 }
 137
 138 /**
 139  * tipc_service_find_range - find service range matching a service instance
 140  *
 141  * Very time-critical, so binary search through range rb tree
 142  */
 143 static struct service_range *tipc_service_find_range(struct tipc_service *sc,
 144                                                      u32 instance)
 145 {
 146         struct rb_node *n = sc->ranges.rb_node;
 147         struct service_range *sr;
 148
 149         while (n) {
 150                 sr = container_of(n, struct service_range, tree_node);
 151                 if (sr->lower > instance)
 152                         n = n->rb_left;
 153                 else if (sr->upper < instance)
 154                         n = n->rb_right;
 155                 else
 156                         return sr;
 157         }
 158         return NULL;
 159 }
 160
 161 static struct service_range *tipc_service_create_range(struct tipc_service *sc,
 162                                                        u32 lower, u32 upper)
 163 {
 164         struct rb_node **n, *parent = NULL;
 165         struct service_range *sr, *tmp;
 166
 167         n = &sc->ranges.rb_node;
 168         while (*n) {
 169                 tmp = container_of(*n, struct service_range, tree_node);
 170                 parent = *n;
 171                 tmp = container_of(parent, struct service_range, tree_node);
 172                 if (lower < tmp->lower)
 173                         n = &(*n)->rb_left;
 174                 else if (lower > tmp->lower)
 175                         n = &(*n)->rb_right;
 176                 else if (upper < tmp->upper)
 177                         n = &(*n)->rb_left;
 178                 else if (upper > tmp->upper)
 179                         n = &(*n)->rb_right;
 180                 else
 181                         return tmp;
 182         }
 183         sr = kzalloc(sizeof(*sr), GFP_ATOMIC);
 184         if (!sr)
 185                 return NULL;
 186         sr->lower = lower;
 187         sr->upper = upper;
 188         INIT_LIST_HEAD(&sr->local_publ);
 189         INIT_LIST_HEAD(&sr->all_publ);
 190         rb_link_node(&sr->tree_node, parent, n);
 191         rb_insert_color(&sr->tree_node, &sc->ranges);
 192         return sr;
 193 }
 194
 195 static struct publication *tipc_service_insert_publ(struct net *net,
 196                                                     struct tipc_service *sc,
 197                                                     u32 type, u32 lower,
 198                                                     u32 upper, u32 scope,
 199                                                     u32 node, u32 port,
 200                                                     u32 key)
 201 {
 202         struct tipc_subscription *sub, *tmp;
 203         struct service_range *sr;
 204         struct publication *p;
 205         bool first = false;
 206
 207         sr = tipc_service_create_range(sc, lower, upper);
 208         if (!sr)
 209                 goto  err;
 210
 211         first = list_empty(&sr->all_publ);
 212
 213         /* Return if the publication already exists */
 214         list_for_each_entry(p, &sr->all_publ, all_publ) {
 215                 if (p->key == key && (!p->node || p->node == node))
 216                         return NULL;
 217         }
 218
 219         /* Create and insert publication */
 220         p = tipc_publ_create(type, lower, upper, scope, node, port, key);
 221         if (!p)
 222                 goto err;
 223         if (in_own_node(net, node))
 224                 list_add(&p->local_publ, &sr->local_publ);
 225         list_add(&p->all_publ, &sr->all_publ);
 226
 227         /* Any subscriptions waiting for notification?  */
 228         list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) {
 229                 tipc_sub_report_overlap(sub, p->lower, p->upper, TIPC_PUBLISHED,
 230                                         p->port, p->node, p->scope, first);
 231         }
 232         return p;
 233 err:
 234         pr_warn("Failed to bind to %u,%u,%u, no memory\n", type, lower, upper);
 235         return NULL;
 236 }
 237
 238 /**
 239  * tipc_service_remove_publ - remove a publication from a service
 240  */
 241 static struct publication *tipc_service_remove_publ(struct net *net,
 242                                                     struct tipc_service *sc,
 243                                                     u32 lower, u32 upper,
 244                                                     u32 node, u32 key)
 245 {
 246         struct tipc_subscription *sub, *tmp;
 247         struct service_range *sr;
 248         struct publication *p;
 249         bool found = false;
 250         bool last = false;
 251         struct rb_node *n;
 252
 253         sr = tipc_service_find_range(sc, lower);
 254         if (!sr)
 255                 return NULL;
 256
 257         /* Find exact matching service range */
 258         for (n = &sr->tree_node; n; n = rb_next(n)) {
 259                 sr = container_of(n, struct service_range, tree_node);
 260                 if (sr->upper == upper)
 261                         break;
 262         }
 263         if (!n || sr->lower != lower || sr->upper != upper)
 264                 return NULL;
 265
 266         /* Find publication, if it exists */
 267         list_for_each_entry(p, &sr->all_publ, all_publ) {
 268                 if (p->key != key || (node && node != p->node))
 269                         continue;
 270                 found = true;
 271                 break;
 272         }
 273         if (!found)
 274                 return NULL;
 275
 276         list_del(&p->all_publ);
 277         list_del(&p->local_publ);
 278
 279         /* Remove service range item if this was its last publication */
 280         if (list_empty(&sr->all_publ)) {
 281                 last = true;
 282                 rb_erase(&sr->tree_node, &sc->ranges);
 283                 kfree(sr);
 284         }
 285
 286         /* Notify any waiting subscriptions */
 287         list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) {
 288                 tipc_sub_report_overlap(sub, p->lower, p->upper, TIPC_WITHDRAWN,
 289                                         p->port, p->node, p->scope, last);
 290         }
 291         return p;
 292 }
 293
 294 /**
 295  * tipc_service_subscribe - attach a subscription, and optionally
 296  * issue the prescribed number of events if there is any service
 297  * range overlapping with the requested range
 298  */
 299 static void tipc_service_subscribe(struct tipc_service *service,
 300                                    struct tipc_subscription *sub)
 301 {
 302         struct tipc_subscr *sb = &sub->evt.s;
 303         struct service_range *sr;
 304         struct tipc_name_seq ns;
 305         struct publication *p;
 306         struct rb_node *n;
 307         bool first;
 308
 309         ns.type = tipc_sub_read(sb, seq.type);
 310         ns.lower = tipc_sub_read(sb, seq.lower);
 311         ns.upper = tipc_sub_read(sb, seq.upper);
 312
 313         tipc_sub_get(sub);
 314         list_add(&sub->service_list, &service->subscriptions);
 315
 316         if (tipc_sub_read(sb, filter) & TIPC_SUB_NO_STATUS)
 317                 return;
 318
 319         for (n = rb_first(&service->ranges); n; n = rb_next(n)) {
 320                 sr = container_of(n, struct service_range, tree_node);
 321                 if (sr->lower > ns.upper)
 322                         break;
 323                 if (!tipc_sub_check_overlap(&ns, sr->lower, sr->upper))
 324                         continue;
 325                 first = true;
 326
 327                 list_for_each_entry(p, &sr->all_publ, all_publ) {
 328                         tipc_sub_report_overlap(sub, sr->lower, sr->upper,
 329                                                 TIPC_PUBLISHED, p->port,
 330                                                 p->node, p->scope, first);
 331                         first = false;
 332                 }
 333         }
 334 }
 335
 336 static struct tipc_service *tipc_service_find(struct net *net, u32 type)
 337 {
 338         struct name_table *nt = tipc_name_table(net);
 339         struct hlist_head *service_head;
 340         struct tipc_service *service;
 341
 342         service_head = &nt->services[hash(type)];
 343         hlist_for_each_entry_rcu(service, service_head, service_list) {
 344                 if (service->type == type)
 345                         return service;
 346         }
 347         return NULL;
 348 };
 349
 350 struct publication *tipc_nametbl_insert_publ(struct net *net, u32 type,
 351                                              u32 lower, u32 upper,
 352                                              u32 scope, u32 node,
 353                                              u32 port, u32 key)
 354 {
 355         struct name_table *nt = tipc_name_table(net);
 356         struct tipc_service *sc;
 357         struct publication *p;
 358
 359         if (scope > TIPC_NODE_SCOPE || lower > upper) {
 360                 pr_debug("Failed to bind illegal {%u,%u,%u} with scope %u\n",
 361                          type, lower, upper, scope);
 362                 return NULL;
 363         }
 364         sc = tipc_service_find(net, type);
 365         if (!sc)
 366                 sc = tipc_service_create(type, &nt->services[hash(type)]);
 367         if (!sc)
 368                 return NULL;
 369
 370         spin_lock_bh(&sc->lock);
 371         p = tipc_service_insert_publ(net, sc, type, lower, upper,
 372                                      scope, node, port, key);
 373         spin_unlock_bh(&sc->lock);
 374         return p;
 375 }
 376
 377 struct publication *tipc_nametbl_remove_publ(struct net *net, u32 type,
 378                                              u32 lower, u32 upper,
 379                                              u32 node, u32 key)
 380 {
 381         struct tipc_service *sc = tipc_service_find(net, type);
 382         struct publication *p = NULL;
 383
 384         if (!sc)
 385                 return NULL;
 386
 387         spin_lock_bh(&sc->lock);
 388         p = tipc_service_remove_publ(net, sc, lower, upper, node, key);
 389
 390         /* Delete service item if this no more publications and subscriptions */
 391         if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) {
 392                 hlist_del_init_rcu(&sc->service_list);
 393                 kfree_rcu(sc, rcu);
 394         }
 395         spin_unlock_bh(&sc->lock);
 396         return p;
 397 }
 398
 399 /**
 400  * tipc_nametbl_translate - perform service instance to socket translation
 401  *
 402  * On entry, 'dnode' is the search domain used during translation.
 403  *
 404  * On exit:
 405  * - if translation is deferred to another node, leave 'dnode' unchanged and
 406  *   return 0
 407  * - if translation is attempted and succeeds, set 'dnode' to the publishing
 408  *   node and return the published (non-zero) port number
 409  * - if translation is attempted and fails, set 'dnode' to 0 and return 0
 410  *
 411  * Note that for legacy users (node configured with Z.C.N address format) the
 412  * 'closest-first' lookup algorithm must be maintained, i.e., if dnode is 0
 413  * we must look in the local binding list first
 414  */
 415 u32 tipc_nametbl_translate(struct net *net, u32 type, u32 instance, u32 *dnode)
 416 {
 417         struct tipc_net *tn = tipc_net(net);
 418         bool legacy = tn->legacy_addr_format;
 419         u32 self = tipc_own_addr(net);
 420         struct service_range *sr;
 421         struct tipc_service *sc;
 422         struct list_head *list;
 423         struct publication *p;
 424         u32 port = 0;
 425         u32 node = 0;
 426
 427         if (!tipc_in_scope(legacy, *dnode, self))
 428                 return 0;
 429
 430         rcu_read_lock();
 431         sc = tipc_service_find(net, type);
 432         if (unlikely(!sc))
 433                 goto not_found;
 434
 435         spin_lock_bh(&sc->lock);
 436         sr = tipc_service_find_range(sc, instance);
 437         if (unlikely(!sr))
 438                 goto no_match;
 439
 440         /* Select lookup algorithm: local, closest-first or round-robin */
 441         if (*dnode == self) {
 442                 list = &sr->local_publ;
 443                 if (list_empty(list))
 444                         goto no_match;
 445                 p = list_first_entry(list, struct publication, local_publ);
 446                 list_move_tail(&p->local_publ, &sr->local_publ);
 447         } else if (legacy && !*dnode && !list_empty(&sr->local_publ)) {
 448                 list = &sr->local_publ;
 449                 p = list_first_entry(list, struct publication, local_publ);
 450                 list_move_tail(&p->local_publ, &sr->local_publ);
 451         } else {
 452                 list = &sr->all_publ;
 453                 p = list_first_entry(list, struct publication, all_publ);
 454                 list_move_tail(&p->all_publ, &sr->all_publ);
 455         }
 456         port = p->port;
 457         node = p->node;
 458 no_match:
 459         spin_unlock_bh(&sc->lock);
 460 not_found:
 461         rcu_read_unlock();
 462         *dnode = node;
 463         return port;
 464 }
 465
 466 bool tipc_nametbl_lookup(struct net *net, u32 type, u32 instance, u32 scope,
 467                          struct list_head *dsts, int *dstcnt, u32 exclude,
 468                          bool all)
 469 {
 470         u32 self = tipc_own_addr(net);
 471         struct service_range *sr;
 472         struct tipc_service *sc;
 473         struct publication *p;
 474
 475         *dstcnt = 0;
 476         rcu_read_lock();
 477         sc = tipc_service_find(net, type);
 478         if (unlikely(!sc))
 479                 goto exit;
 480
 481         spin_lock_bh(&sc->lock);
 482
 483         sr = tipc_service_find_range(sc, instance);
 484         if (!sr)
 485                 goto no_match;
 486
 487         list_for_each_entry(p, &sr->all_publ, all_publ) {
 488                 if (p->scope != scope)
 489                         continue;
 490                 if (p->port == exclude && p->node == self)
 491                         continue;
 492                 tipc_dest_push(dsts, p->node, p->port);
 493                 (*dstcnt)++;
 494                 if (all)
 495                         continue;
 496                 list_move_tail(&p->all_publ, &sr->all_publ);
 497                 break;
 498         }
 499 no_match:
 500         spin_unlock_bh(&sc->lock);
 501 exit:
 502         rcu_read_unlock();
 503         return !list_empty(dsts);
 504 }
 505
 506 void tipc_nametbl_mc_lookup(struct net *net, u32 type, u32 lower, u32 upper,
 507                             u32 scope, bool exact, struct list_head *dports)
 508 {
 509         struct service_range *sr;
 510         struct tipc_service *sc;
 511         struct publication *p;
 512         struct rb_node *n;
 513
 514         rcu_read_lock();
 515         sc = tipc_service_find(net, type);
 516         if (!sc)
 517                 goto exit;
 518
 519         spin_lock_bh(&sc->lock);
 520
 521         for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
 522                 sr = container_of(n, struct service_range, tree_node);
 523                 if (sr->upper < lower)
 524                         continue;
 525                 if (sr->lower > upper)
 526                         break;
 527                 list_for_each_entry(p, &sr->local_publ, local_publ) {
 528                         if (p->scope == scope || (!exact && p->scope < scope))
 529                                 tipc_dest_push(dports, 0, p->port);
 530                 }
 531         }
 532         spin_unlock_bh(&sc->lock);
 533 exit:
 534         rcu_read_unlock();
 535 }
 536
 537 /* tipc_nametbl_lookup_dst_nodes - find broadcast destination nodes
 538  * - Creates list of nodes that overlap the given multicast address
 539  * - Determines if any node local destinations overlap
 540  */
 541 void tipc_nametbl_lookup_dst_nodes(struct net *net, u32 type, u32 lower,
 542                                    u32 upper, struct tipc_nlist *nodes)
 543 {
 544         struct service_range *sr;
 545         struct tipc_service *sc;
 546         struct publication *p;
 547         struct rb_node *n;
 548
 549         rcu_read_lock();
 550         sc = tipc_service_find(net, type);
 551         if (!sc)
 552                 goto exit;
 553
 554         spin_lock_bh(&sc->lock);
 555
 556         for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
 557                 sr = container_of(n, struct service_range, tree_node);
 558                 if (sr->upper < lower)
 559                         continue;
 560                 if (sr->lower > upper)
 561                         break;
 562                 list_for_each_entry(p, &sr->all_publ, all_publ) {
 563                         tipc_nlist_add(nodes, p->node);
 564                 }
 565         }
 566         spin_unlock_bh(&sc->lock);
 567 exit:
 568         rcu_read_unlock();
 569 }
 570
 571 /* tipc_nametbl_build_group - build list of communication group members
 572  */
 573 void tipc_nametbl_build_group(struct net *net, struct tipc_group *grp,
 574                               u32 type, u32 scope)
 575 {
 576         struct service_range *sr;
 577         struct tipc_service *sc;
 578         struct publication *p;
 579         struct rb_node *n;
 580
 581         rcu_read_lock();
 582         sc = tipc_service_find(net, type);
 583         if (!sc)
 584                 goto exit;
 585
 586         spin_lock_bh(&sc->lock);
 587         for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
 588                 sr = container_of(n, struct service_range, tree_node);
 589                 list_for_each_entry(p, &sr->all_publ, all_publ) {
 590                         if (p->scope != scope)
 591                                 continue;
 592                         tipc_group_add_member(grp, p->node, p->port, p->lower);
 593                 }
 594         }
 595         spin_unlock_bh(&sc->lock);
 596 exit:
 597         rcu_read_unlock();
 598 }
 599
 600 /* tipc_nametbl_publish - add service binding to name table
 601  */
 602 struct publication *tipc_nametbl_publish(struct net *net, u32 type, u32 lower,
 603                                          u32 upper, u32 scope, u32 port,
 604                                          u32 key)
 605 {
 606         struct name_table *nt = tipc_name_table(net);
 607         struct tipc_net *tn = tipc_net(net);
 608         struct publication *p = NULL;
 609         struct sk_buff *skb = NULL;
 610
 611         spin_lock_bh(&tn->nametbl_lock);
 612
 613         if (nt->local_publ_count >= TIPC_MAX_PUBL) {
 614                 pr_warn("Bind failed, max limit %u reached\n", TIPC_MAX_PUBL);
 615                 goto exit;
 616         }
 617
 618         p = tipc_nametbl_insert_publ(net, type, lower, upper, scope,
 619                                      tipc_own_addr(net), port, key);
 620         if (p) {
 621                 nt->local_publ_count++;
 622                 skb = tipc_named_publish(net, p);
 623         }
 624 exit:
 625         spin_unlock_bh(&tn->nametbl_lock);
 626
 627         if (skb)
 628                 tipc_node_broadcast(net, skb);
 629         return p;
 630 }
 631
 632 /**
 633  * tipc_nametbl_withdraw - withdraw a service binding
 634  */
 635 int tipc_nametbl_withdraw(struct net *net, u32 type, u32 lower,
 636                           u32 upper, u32 key)
 637 {
 638         struct name_table *nt = tipc_name_table(net);
 639         struct tipc_net *tn = tipc_net(net);
 640         u32 self = tipc_own_addr(net);
 641         struct sk_buff *skb = NULL;
 642         struct publication *p;
 643
 644         spin_lock_bh(&tn->nametbl_lock);
 645
 646         p = tipc_nametbl_remove_publ(net, type, lower, upper, self, key);
 647         if (p) {
 648                 nt->local_publ_count--;
 649                 skb = tipc_named_withdraw(net, p);
 650                 list_del_init(&p->binding_sock);
 651                 kfree_rcu(p, rcu);
 652         } else {
 653                 pr_err("Failed to remove local publication {%u,%u,%u}/%u\n",
 654                        type, lower, upper, key);
 655         }
 656         spin_unlock_bh(&tn->nametbl_lock);
 657
 658         if (skb) {
 659                 tipc_node_broadcast(net, skb);
 660                 return 1;
 661         }
 662         return 0;
 663 }
 664
 665 /**
 666  * tipc_nametbl_subscribe - add a subscription object to the name table
 667  */
 668 void tipc_nametbl_subscribe(struct tipc_subscription *sub)
 669 {
 670         struct name_table *nt = tipc_name_table(sub->net);
 671         struct tipc_net *tn = tipc_net(sub->net);
 672         struct tipc_subscr *s = &sub->evt.s;
 673         u32 type = tipc_sub_read(s, seq.type);
 674         struct tipc_service *sc;
 675
 676         spin_lock_bh(&tn->nametbl_lock);
 677         sc = tipc_service_find(sub->net, type);
 678         if (!sc)
 679                 sc = tipc_service_create(type, &nt->services[hash(type)]);
 680         if (sc) {
 681                 spin_lock_bh(&sc->lock);
 682                 tipc_service_subscribe(sc, sub);
 683                 spin_unlock_bh(&sc->lock);
 684         } else {
 685                 pr_warn("Failed to subscribe for {%u,%u,%u}\n", type,
 686                         tipc_sub_read(s, seq.lower),
 687                         tipc_sub_read(s, seq.upper));
 688         }
 689         spin_unlock_bh(&tn->nametbl_lock);
 690 }
 691
 692 /**
 693  * tipc_nametbl_unsubscribe - remove a subscription object from name table
 694  */
 695 void tipc_nametbl_unsubscribe(struct tipc_subscription *sub)
 696 {
 697         struct tipc_net *tn = tipc_net(sub->net);
 698         struct tipc_subscr *s = &sub->evt.s;
 699         u32 type = tipc_sub_read(s, seq.type);
 700         struct tipc_service *sc;
 701
 702         spin_lock_bh(&tn->nametbl_lock);
 703         sc = tipc_service_find(sub->net, type);
 704         if (!sc)
 705                 goto exit;
 706
 707         spin_lock_bh(&sc->lock);
 708         list_del_init(&sub->service_list);
 709         tipc_sub_put(sub);
 710
 711         /* Delete service item if no more publications and subscriptions */
 712         if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) {
 713                 hlist_del_init_rcu(&sc->service_list);
 714                 kfree_rcu(sc, rcu);
 715         }
 716         spin_unlock_bh(&sc->lock);
 717 exit:
 718         spin_unlock_bh(&tn->nametbl_lock);
 719 }
 720
 721 int tipc_nametbl_init(struct net *net)
 722 {
 723         struct tipc_net *tn = tipc_net(net);
 724         struct name_table *nt;
 725         int i;
 726
 727         nt = kzalloc(sizeof(*nt), GFP_ATOMIC);
 728         if (!nt)
 729                 return -ENOMEM;
 730
 731         for (i = 0; i < TIPC_NAMETBL_SIZE; i++)
 732                 INIT_HLIST_HEAD(&nt->services[i]);
 733
 734         INIT_LIST_HEAD(&nt->node_scope);
 735         INIT_LIST_HEAD(&nt->cluster_scope);
 736         tn->nametbl = nt;
 737         spin_lock_init(&tn->nametbl_lock);
 738         return 0;
 739 }
 740
 741 /**
 742  *  tipc_service_delete - purge all publications for a service and delete it
 743  */
 744 static void tipc_service_delete(struct net *net, struct tipc_service *sc)
 745 {
 746         struct service_range *sr, *tmpr;
 747         struct publication *p, *tmpb;
 748
 749         spin_lock_bh(&sc->lock);
 750         rbtree_postorder_for_each_entry_safe(sr, tmpr, &sc->ranges, tree_node) {
 751                 list_for_each_entry_safe(p, tmpb,
 752                                          &sr->all_publ, all_publ) {
 753                         tipc_service_remove_publ(net, sc, p->lower, p->upper,
 754                                                  p->node, p->key);
 755                         kfree_rcu(p, rcu);
 756                 }
 757         }
 758         hlist_del_init_rcu(&sc->service_list);
 759         spin_unlock_bh(&sc->lock);
 760         kfree_rcu(sc, rcu);
 761 }
 762
 763 void tipc_nametbl_stop(struct net *net)
 764 {
 765         struct name_table *nt = tipc_name_table(net);
 766         struct tipc_net *tn = tipc_net(net);
 767         struct hlist_head *service_head;
 768         struct tipc_service *service;
 769         u32 i;
 770
 771         /* Verify name table is empty and purge any lingering
 772          * publications, then release the name table
 773          */
 774         spin_lock_bh(&tn->nametbl_lock);
 775         for (i = 0; i < TIPC_NAMETBL_SIZE; i++) {
 776                 if (hlist_empty(&nt->services[i]))
 777                         continue;
 778                 service_head = &nt->services[i];
 779                 hlist_for_each_entry_rcu(service, service_head, service_list) {
 780                         tipc_service_delete(net, service);
 781                 }
 782         }
 783         spin_unlock_bh(&tn->nametbl_lock);
 784
 785         synchronize_net();
 786         kfree(nt);
 787 }
 788
 789 static int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg,
 790                                         struct tipc_service *service,
 791                                         struct service_range *sr,
 792                                         u32 *last_key)
 793 {
 794         struct publication *p;
 795         struct nlattr *attrs;
 796         struct nlattr *b;
 797         void *hdr;
 798
 799         if (*last_key) {
 800                 list_for_each_entry(p, &sr->all_publ, all_publ)
 801                         if (p->key == *last_key)
 802                                 break;
 803                 if (p->key != *last_key)
 804                         return -EPIPE;
 805         } else {
 806                 p = list_first_entry(&sr->all_publ,
 807                                      struct publication,
 808                                      all_publ);
 809         }
 810
 811         list_for_each_entry_from(p, &sr->all_publ, all_publ) {
 812                 *last_key = p->key;
 813
 814                 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq,
 815                                   &tipc_genl_family, NLM_F_MULTI,
 816                                   TIPC_NL_NAME_TABLE_GET);
 817                 if (!hdr)
 818                         return -EMSGSIZE;
 819
 820                 attrs = nla_nest_start(msg->skb, TIPC_NLA_NAME_TABLE);
 821                 if (!attrs)
 822                         goto msg_full;
 823
 824                 b = nla_nest_start(msg->skb, TIPC_NLA_NAME_TABLE_PUBL);
 825                 if (!b)
 826                         goto attr_msg_full;
 827
 828                 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, service->type))
 829                         goto publ_msg_full;
 830                 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sr->lower))
 831                         goto publ_msg_full;
 832                 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sr->upper))
 833                         goto publ_msg_full;
 834                 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope))
 835                         goto publ_msg_full;
 836                 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->node))
 837                         goto publ_msg_full;
 838                 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->port))
 839                         goto publ_msg_full;
 840                 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key))
 841                         goto publ_msg_full;
 842
 843                 nla_nest_end(msg->skb, b);
 844                 nla_nest_end(msg->skb, attrs);
 845                 genlmsg_end(msg->skb, hdr);
 846         }
 847         *last_key = 0;
 848
 849         return 0;
 850
 851 publ_msg_full:
 852         nla_nest_cancel(msg->skb, b);
 853 attr_msg_full:
 854         nla_nest_cancel(msg->skb, attrs);
 855 msg_full:
 856         genlmsg_cancel(msg->skb, hdr);
 857
 858         return -EMSGSIZE;
 859 }
 860
 861 static int __tipc_nl_service_range_list(struct tipc_nl_msg *msg,
 862                                         struct tipc_service *sc,
 863                                         u32 *last_lower, u32 *last_key)
 864 {
 865         struct service_range *sr;
 866         struct rb_node *n;
 867         int err;
 868
 869         for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
 870                 sr = container_of(n, struct service_range, tree_node);
 871                 if (sr->lower < *last_lower)
 872                         continue;
 873                 err = __tipc_nl_add_nametable_publ(msg, sc, sr, last_key);
 874                 if (err) {
 875                         *last_lower = sr->lower;
 876                         return err;
 877                 }
 878         }
 879         *last_lower = 0;
 880         return 0;
 881 }
 882
 883 static int tipc_nl_service_list(struct net *net, struct tipc_nl_msg *msg,
 884                                 u32 *last_type, u32 *last_lower, u32 *last_key)
 885 {
 886         struct tipc_net *tn = tipc_net(net);
 887         struct tipc_service *service = NULL;
 888         struct hlist_head *head;
 889         int err;
 890         int i;
 891
 892         if (*last_type)
 893                 i = hash(*last_type);
 894         else
 895                 i = 0;
 896
 897         for (; i < TIPC_NAMETBL_SIZE; i++) {
 898                 head = &tn->nametbl->services[i];
 899
 900                 if (*last_type) {
 901                         service = tipc_service_find(net, *last_type);
 902                         if (!service)
 903                                 return -EPIPE;
 904                 } else {
 905                         hlist_for_each_entry_rcu(service, head, service_list)
 906                                 break;
 907                         if (!service)
 908                                 continue;
 909                 }
 910
 911                 hlist_for_each_entry_from_rcu(service, service_list) {
 912                         spin_lock_bh(&service->lock);
 913                         err = __tipc_nl_service_range_list(msg, service,
 914                                                            last_lower,
 915                                                            last_key);
 916
 917                         if (err) {
 918                                 *last_type = service->type;
 919                                 spin_unlock_bh(&service->lock);
 920                                 return err;
 921                         }
 922                         spin_unlock_bh(&service->lock);
 923                 }
 924                 *last_type = 0;
 925         }
 926         return 0;
 927 }
 928
 929 int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb)
 930 {
 931         struct net *net = sock_net(skb->sk);
 932         u32 last_type = cb->args[0];
 933         u32 last_lower = cb->args[1];
 934         u32 last_key = cb->args[2];
 935         int done = cb->args[3];
 936         struct tipc_nl_msg msg;
 937         int err;
 938
 939         if (done)
 940                 return 0;
 941
 942         msg.skb = skb;
 943         msg.portid = NETLINK_CB(cb->skb).portid;
 944         msg.seq = cb->nlh->nlmsg_seq;
 945
 946         rcu_read_lock();
 947         err = tipc_nl_service_list(net, &msg, &last_type,
 948                                    &last_lower, &last_key);
 949         if (!err) {
 950                 done = 1;
 951         } else if (err != -EMSGSIZE) {
 952                 /* We never set seq or call nl_dump_check_consistent() this
 953                  * means that setting prev_seq here will cause the consistence
 954                  * check to fail in the netlink callback handler. Resulting in
 955                  * the NLMSG_DONE message having the NLM_F_DUMP_INTR flag set if
 956                  * we got an error.
 957                  */
 958                 cb->prev_seq = 1;
 959         }
 960         rcu_read_unlock();
 961
 962         cb->args[0] = last_type;
 963         cb->args[1] = last_lower;
 964         cb->args[2] = last_key;
 965         cb->args[3] = done;
 966
 967         return skb->len;
 968 }
 969
 970 struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port)
 971 {
 972         u64 value = (u64)node << 32 | port;
 973         struct tipc_dest *dst;
 974
 975         list_for_each_entry(dst, l, list) {
 976                 if (dst->value != value)
 977                         continue;
 978                 return dst;
 979         }
 980         return NULL;
 981 }
 982
 983 bool tipc_dest_push(struct list_head *l, u32 node, u32 port)
 984 {
 985         u64 value = (u64)node << 32 | port;
 986         struct tipc_dest *dst;
 987
 988         if (tipc_dest_find(l, node, port))
 989                 return false;
 990
 991         dst = kmalloc(sizeof(*dst), GFP_ATOMIC);
 992         if (unlikely(!dst))
 993                 return false;
 994         dst->value = value;
 995         list_add(&dst->list, l);
 996         return true;
 997 }
 998
 999 bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port)
1000 {
1001         struct tipc_dest *dst;
1002
1003         if (list_empty(l))
1004                 return false;
1005         dst = list_first_entry(l, typeof(*dst), list);
1006         if (port)
1007                 *port = dst->port;
1008         if (node)
1009                 *node = dst->node;
1010         list_del(&dst->list);
1011         kfree(dst);
1012         return true;
1013 }
1014
1015 bool tipc_dest_del(struct list_head *l, u32 node, u32 port)
1016 {
1017         struct tipc_dest *dst;
1018
1019         dst = tipc_dest_find(l, node, port);
1020         if (!dst)
1021                 return false;
1022         list_del(&dst->list);
1023         kfree(dst);
1024         return true;
1025 }
1026
1027 void tipc_dest_list_purge(struct list_head *l)
1028 {
1029         struct tipc_dest *dst, *tmp;
1030
1031         list_for_each_entry_safe(dst, tmp, l, list) {
1032                 list_del(&dst->list);
1033                 kfree(dst);
1034         }
1035 }
1036
1037 int tipc_dest_list_len(struct list_head *l)
1038 {
1039         struct tipc_dest *dst;
1040         int i = 0;
1041
1042         list_for_each_entry(dst, l, list) {
1043                 i++;
1044         }
1045         return i;
1046 }