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 <linux/list_sort.h>
  39 #include "core.h"
  40 #include "netlink.h"
  41 #include "name_table.h"
  42 #include "name_distr.h"
  43 #include "subscr.h"
  44 #include "bcast.h"
  45 #include "addr.h"
  46 #include "node.h"
  47 #include "group.h"
  48
  49 /**
  50  * struct service_range - container for all bindings of a service range
  51  * @lower: service range lower bound
  52  * @upper: service range upper bound
  53  * @tree_node: member of service range RB tree
  54  * @local_publ: list of identical publications made from this node
  55  *   Used by closest_first lookup and multicast lookup algorithm
  56  * @all_publ: all publications identical to this one, whatever node and scope
  57  *   Used by round-robin lookup algorithm
  58  */
  59 struct service_range {
  60         u32 lower;
  61         u32 upper;
  62         struct rb_node tree_node;
  63         struct list_head local_publ;
  64         struct list_head all_publ;
  65 };
  66
  67 /**
  68  * struct tipc_service - container for all published instances of a service type
  69  * @type: 32 bit 'type' value for service
  70  * @publ_cnt: increasing counter for publications in this service
  71  * @ranges: rb tree containing all service ranges for this service
  72  * @service_list: links to adjacent name ranges in hash chain
  73  * @subscriptions: list of subscriptions for this service type
  74  * @lock: spinlock controlling access to pertaining service ranges/publications
  75  * @rcu: RCU callback head used for deferred freeing
  76  */
  77 struct tipc_service {
  78         u32 type;
  79         u32 publ_cnt;
  80         struct rb_root ranges;
  81         struct hlist_node service_list;
  82         struct list_head subscriptions;
  83         spinlock_t lock; /* Covers service range list */
  84         struct rcu_head rcu;
  85 };
  86
  87 static int hash(int x)
  88 {
  89         return x & (TIPC_NAMETBL_SIZE - 1);
  90 }
  91
  92 /**
  93  * tipc_publ_create - create a publication structure
  94  */
  95 static struct publication *tipc_publ_create(u32 type, u32 lower, u32 upper,
  96                                             u32 scope, u32 node, u32 port,
  97                                             u32 key)
  98 {
  99         struct publication *publ = kzalloc(sizeof(*publ), GFP_ATOMIC);
 100
 101         if (!publ)
 102                 return NULL;
 103
 104         publ->type = type;
 105         publ->lower = lower;
 106         publ->upper = upper;
 107         publ->scope = scope;
 108         publ->node = node;
 109         publ->port = port;
 110         publ->key = key;
 111         INIT_LIST_HEAD(&publ->binding_sock);
 112         INIT_LIST_HEAD(&publ->binding_node);
 113         INIT_LIST_HEAD(&publ->local_publ);
 114         INIT_LIST_HEAD(&publ->all_publ);
 115         INIT_LIST_HEAD(&publ->list);
 116         return publ;
 117 }
 118
 119 /**
 120  * tipc_service_create - create a service structure for the specified 'type'
 121  *
 122  * Allocates a single range structure and sets it to all 0's.
 123  */
 124 static struct tipc_service *tipc_service_create(u32 type, struct hlist_head *hd)
 125 {
 126         struct tipc_service *service = kzalloc(sizeof(*service), GFP_ATOMIC);
 127
 128         if (!service) {
 129                 pr_warn("Service creation failed, no memory\n");
 130                 return NULL;
 131         }
 132
 133         spin_lock_init(&service->lock);
 134         service->type = type;
 135         service->ranges = RB_ROOT;
 136         INIT_HLIST_NODE(&service->service_list);
 137         INIT_LIST_HEAD(&service->subscriptions);
 138         hlist_add_head_rcu(&service->service_list, hd);
 139         return service;
 140 }
 141
 142 /**
 143  * tipc_service_first_range - find first service range in tree matching instance
 144  *
 145  * Very time-critical, so binary search through range rb tree
 146  */
 147 static struct service_range *tipc_service_first_range(struct tipc_service *sc,
 148                                                       u32 instance)
 149 {
 150         struct rb_node *n = sc->ranges.rb_node;
 151         struct service_range *sr;
 152
 153         while (n) {
 154                 sr = container_of(n, struct service_range, tree_node);
 155                 if (sr->lower > instance)
 156                         n = n->rb_left;
 157                 else if (sr->upper < instance)
 158                         n = n->rb_right;
 159                 else
 160                         return sr;
 161         }
 162         return NULL;
 163 }
 164
 165 /*  tipc_service_find_range - find service range matching publication parameters
 166  */
 167 static struct service_range *tipc_service_find_range(struct tipc_service *sc,
 168                                                      u32 lower, u32 upper)
 169 {
 170         struct rb_node *n = sc->ranges.rb_node;
 171         struct service_range *sr;
 172
 173         sr = tipc_service_first_range(sc, lower);
 174         if (!sr)
 175                 return NULL;
 176
 177         /* Look for exact match */
 178         for (n = &sr->tree_node; n; n = rb_next(n)) {
 179                 sr = container_of(n, struct service_range, tree_node);
 180                 if (sr->upper == upper)
 181                         break;
 182         }
 183         if (!n || sr->lower != lower || sr->upper != upper)
 184                 return NULL;
 185
 186         return sr;
 187 }
 188
 189 static struct service_range *tipc_service_create_range(struct tipc_service *sc,
 190                                                        u32 lower, u32 upper)
 191 {
 192         struct rb_node **n, *parent = NULL;
 193         struct service_range *sr, *tmp;
 194
 195         n = &sc->ranges.rb_node;
 196         while (*n) {
 197                 tmp = container_of(*n, struct service_range, tree_node);
 198                 parent = *n;
 199                 tmp = container_of(parent, struct service_range, tree_node);
 200                 if (lower < tmp->lower)
 201                         n = &(*n)->rb_left;
 202                 else if (lower > tmp->lower)
 203                         n = &(*n)->rb_right;
 204                 else if (upper < tmp->upper)
 205                         n = &(*n)->rb_left;
 206                 else if (upper > tmp->upper)
 207                         n = &(*n)->rb_right;
 208                 else
 209                         return tmp;
 210         }
 211         sr = kzalloc(sizeof(*sr), GFP_ATOMIC);
 212         if (!sr)
 213                 return NULL;
 214         sr->lower = lower;
 215         sr->upper = upper;
 216         INIT_LIST_HEAD(&sr->local_publ);
 217         INIT_LIST_HEAD(&sr->all_publ);
 218         rb_link_node(&sr->tree_node, parent, n);
 219         rb_insert_color(&sr->tree_node, &sc->ranges);
 220         return sr;
 221 }
 222
 223 static struct publication *tipc_service_insert_publ(struct net *net,
 224                                                     struct tipc_service *sc,
 225                                                     u32 type, u32 lower,
 226                                                     u32 upper, u32 scope,
 227                                                     u32 node, u32 port,
 228                                                     u32 key)
 229 {
 230         struct tipc_subscription *sub, *tmp;
 231         struct service_range *sr;
 232         struct publication *p;
 233         bool first = false;
 234
 235         sr = tipc_service_create_range(sc, lower, upper);
 236         if (!sr)
 237                 goto  err;
 238
 239         first = list_empty(&sr->all_publ);
 240
 241         /* Return if the publication already exists */
 242         list_for_each_entry(p, &sr->all_publ, all_publ) {
 243                 if (p->key == key && (!p->node || p->node == node))
 244                         return NULL;
 245         }
 246
 247         /* Create and insert publication */
 248         p = tipc_publ_create(type, lower, upper, scope, node, port, key);
 249         if (!p)
 250                 goto err;
 251         /* Suppose there shouldn't be a huge gap btw publs i.e. >INT_MAX */
 252         p->id = sc->publ_cnt++;
 253         if (in_own_node(net, node))
 254                 list_add(&p->local_publ, &sr->local_publ);
 255         list_add(&p->all_publ, &sr->all_publ);
 256
 257         /* Any subscriptions waiting for notification?  */
 258         list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) {
 259                 tipc_sub_report_overlap(sub, p->lower, p->upper, TIPC_PUBLISHED,
 260                                         p->port, p->node, p->scope, first);
 261         }
 262         return p;
 263 err:
 264         pr_warn("Failed to bind to %u,%u,%u, no memory\n", type, lower, upper);
 265         return NULL;
 266 }
 267
 268 /**
 269  * tipc_service_remove_publ - remove a publication from a service
 270  */
 271 static struct publication *tipc_service_remove_publ(struct service_range *sr,
 272                                                     u32 node, u32 key)
 273 {
 274         struct publication *p;
 275
 276         list_for_each_entry(p, &sr->all_publ, all_publ) {
 277                 if (p->key != key || (node && node != p->node))
 278                         continue;
 279                 list_del(&p->all_publ);
 280                 list_del(&p->local_publ);
 281                 return p;
 282         }
 283         return NULL;
 284 }
 285
 286 /**
 287  * Code reused: time_after32() for the same purpose
 288  */
 289 #define publication_after(pa, pb) time_after32((pa)->id, (pb)->id)
 290 static int tipc_publ_sort(void *priv, struct list_head *a,
 291                           struct list_head *b)
 292 {
 293         struct publication *pa, *pb;
 294
 295         pa = container_of(a, struct publication, list);
 296         pb = container_of(b, struct publication, list);
 297         return publication_after(pa, pb);
 298 }
 299
 300 /**
 301  * tipc_service_subscribe - attach a subscription, and optionally
 302  * issue the prescribed number of events if there is any service
 303  * range overlapping with the requested range
 304  */
 305 static void tipc_service_subscribe(struct tipc_service *service,
 306                                    struct tipc_subscription *sub)
 307 {
 308         struct tipc_subscr *sb = &sub->evt.s;
 309         struct publication *p, *first, *tmp;
 310         struct list_head publ_list;
 311         struct service_range *sr;
 312         struct tipc_name_seq ns;
 313         struct rb_node *n;
 314         u32 filter;
 315
 316         ns.type = tipc_sub_read(sb, seq.type);
 317         ns.lower = tipc_sub_read(sb, seq.lower);
 318         ns.upper = tipc_sub_read(sb, seq.upper);
 319         filter = tipc_sub_read(sb, filter);
 320
 321         tipc_sub_get(sub);
 322         list_add(&sub->service_list, &service->subscriptions);
 323
 324         if (filter & TIPC_SUB_NO_STATUS)
 325                 return;
 326
 327         INIT_LIST_HEAD(&publ_list);
 328         for (n = rb_first(&service->ranges); n; n = rb_next(n)) {
 329                 sr = container_of(n, struct service_range, tree_node);
 330                 if (sr->lower > ns.upper)
 331                         break;
 332                 if (!tipc_sub_check_overlap(&ns, sr->lower, sr->upper))
 333                         continue;
 334
 335                 first = NULL;
 336                 list_for_each_entry(p, &sr->all_publ, all_publ) {
 337                         if (filter & TIPC_SUB_PORTS)
 338                                 list_add_tail(&p->list, &publ_list);
 339                         else if (!first || publication_after(first, p))
 340                                 /* Pick this range's *first* publication */
 341                                 first = p;
 342                 }
 343                 if (first)
 344                         list_add_tail(&first->list, &publ_list);
 345         }
 346
 347         /* Sort the publications before reporting */
 348         list_sort(NULL, &publ_list, tipc_publ_sort);
 349         list_for_each_entry_safe(p, tmp, &publ_list, list) {
 350                 tipc_sub_report_overlap(sub, p->lower, p->upper,
 351                                         TIPC_PUBLISHED, p->port, p->node,
 352                                         p->scope, true);
 353                 list_del_init(&p->list);
 354         }
 355 }
 356
 357 static struct tipc_service *tipc_service_find(struct net *net, u32 type)
 358 {
 359         struct name_table *nt = tipc_name_table(net);
 360         struct hlist_head *service_head;
 361         struct tipc_service *service;
 362
 363         service_head = &nt->services[hash(type)];
 364         hlist_for_each_entry_rcu(service, service_head, service_list) {
 365                 if (service->type == type)
 366                         return service;
 367         }
 368         return NULL;
 369 };
 370
 371 struct publication *tipc_nametbl_insert_publ(struct net *net, u32 type,
 372                                              u32 lower, u32 upper,
 373                                              u32 scope, u32 node,
 374                                              u32 port, u32 key)
 375 {
 376         struct name_table *nt = tipc_name_table(net);
 377         struct tipc_service *sc;
 378         struct publication *p;
 379
 380         if (scope > TIPC_NODE_SCOPE || lower > upper) {
 381                 pr_debug("Failed to bind illegal {%u,%u,%u} with scope %u\n",
 382                          type, lower, upper, scope);
 383                 return NULL;
 384         }
 385         sc = tipc_service_find(net, type);
 386         if (!sc)
 387                 sc = tipc_service_create(type, &nt->services[hash(type)]);
 388         if (!sc)
 389                 return NULL;
 390
 391         spin_lock_bh(&sc->lock);
 392         p = tipc_service_insert_publ(net, sc, type, lower, upper,
 393                                      scope, node, port, key);
 394         spin_unlock_bh(&sc->lock);
 395         return p;
 396 }
 397
 398 struct publication *tipc_nametbl_remove_publ(struct net *net, u32 type,
 399                                              u32 lower, u32 upper,
 400                                              u32 node, u32 key)
 401 {
 402         struct tipc_service *sc = tipc_service_find(net, type);
 403         struct tipc_subscription *sub, *tmp;
 404         struct service_range *sr = NULL;
 405         struct publication *p = NULL;
 406         bool last;
 407
 408         if (!sc)
 409                 return NULL;
 410
 411         spin_lock_bh(&sc->lock);
 412         sr = tipc_service_find_range(sc, lower, upper);
 413         if (!sr)
 414                 goto exit;
 415         p = tipc_service_remove_publ(sr, node, key);
 416         if (!p)
 417                 goto exit;
 418
 419         /* Notify any waiting subscriptions */
 420         last = list_empty(&sr->all_publ);
 421         list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) {
 422                 tipc_sub_report_overlap(sub, lower, upper, TIPC_WITHDRAWN,
 423                                         p->port, node, p->scope, last);
 424         }
 425
 426         /* Remove service range item if this was its last publication */
 427         if (list_empty(&sr->all_publ)) {
 428                 rb_erase(&sr->tree_node, &sc->ranges);
 429                 kfree(sr);
 430         }
 431
 432         /* Delete service item if this no more publications and subscriptions */
 433         if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) {
 434                 hlist_del_init_rcu(&sc->service_list);
 435                 kfree_rcu(sc, rcu);
 436         }
 437 exit:
 438         spin_unlock_bh(&sc->lock);
 439         return p;
 440 }
 441
 442 /**
 443  * tipc_nametbl_translate - perform service instance to socket translation
 444  *
 445  * On entry, 'dnode' is the search domain used during translation.
 446  *
 447  * On exit:
 448  * - if translation is deferred to another node, leave 'dnode' unchanged and
 449  *   return 0
 450  * - if translation is attempted and succeeds, set 'dnode' to the publishing
 451  *   node and return the published (non-zero) port number
 452  * - if translation is attempted and fails, set 'dnode' to 0 and return 0
 453  *
 454  * Note that for legacy users (node configured with Z.C.N address format) the
 455  * 'closest-first' lookup algorithm must be maintained, i.e., if dnode is 0
 456  * we must look in the local binding list first
 457  */
 458 u32 tipc_nametbl_translate(struct net *net, u32 type, u32 instance, u32 *dnode)
 459 {
 460         struct tipc_net *tn = tipc_net(net);
 461         bool legacy = tn->legacy_addr_format;
 462         u32 self = tipc_own_addr(net);
 463         struct service_range *sr;
 464         struct tipc_service *sc;
 465         struct list_head *list;
 466         struct publication *p;
 467         u32 port = 0;
 468         u32 node = 0;
 469
 470         if (!tipc_in_scope(legacy, *dnode, self))
 471                 return 0;
 472
 473         rcu_read_lock();
 474         sc = tipc_service_find(net, type);
 475         if (unlikely(!sc))
 476                 goto not_found;
 477
 478         spin_lock_bh(&sc->lock);
 479         sr = tipc_service_first_range(sc, instance);
 480         if (unlikely(!sr))
 481                 goto no_match;
 482
 483         /* Select lookup algorithm: local, closest-first or round-robin */
 484         if (*dnode == self) {
 485                 list = &sr->local_publ;
 486                 if (list_empty(list))
 487                         goto no_match;
 488                 p = list_first_entry(list, struct publication, local_publ);
 489                 list_move_tail(&p->local_publ, &sr->local_publ);
 490         } else if (legacy && !*dnode && !list_empty(&sr->local_publ)) {
 491                 list = &sr->local_publ;
 492                 p = list_first_entry(list, struct publication, local_publ);
 493                 list_move_tail(&p->local_publ, &sr->local_publ);
 494         } else {
 495                 list = &sr->all_publ;
 496                 p = list_first_entry(list, struct publication, all_publ);
 497                 list_move_tail(&p->all_publ, &sr->all_publ);
 498         }
 499         port = p->port;
 500         node = p->node;
 501 no_match:
 502         spin_unlock_bh(&sc->lock);
 503 not_found:
 504         rcu_read_unlock();
 505         *dnode = node;
 506         return port;
 507 }
 508
 509 bool tipc_nametbl_lookup(struct net *net, u32 type, u32 instance, u32 scope,
 510                          struct list_head *dsts, int *dstcnt, u32 exclude,
 511                          bool all)
 512 {
 513         u32 self = tipc_own_addr(net);
 514         struct service_range *sr;
 515         struct tipc_service *sc;
 516         struct publication *p;
 517
 518         *dstcnt = 0;
 519         rcu_read_lock();
 520         sc = tipc_service_find(net, type);
 521         if (unlikely(!sc))
 522                 goto exit;
 523
 524         spin_lock_bh(&sc->lock);
 525
 526         sr = tipc_service_first_range(sc, instance);
 527         if (!sr)
 528                 goto no_match;
 529
 530         list_for_each_entry(p, &sr->all_publ, all_publ) {
 531                 if (p->scope != scope)
 532                         continue;
 533                 if (p->port == exclude && p->node == self)
 534                         continue;
 535                 tipc_dest_push(dsts, p->node, p->port);
 536                 (*dstcnt)++;
 537                 if (all)
 538                         continue;
 539                 list_move_tail(&p->all_publ, &sr->all_publ);
 540                 break;
 541         }
 542 no_match:
 543         spin_unlock_bh(&sc->lock);
 544 exit:
 545         rcu_read_unlock();
 546         return !list_empty(dsts);
 547 }
 548
 549 void tipc_nametbl_mc_lookup(struct net *net, u32 type, u32 lower, u32 upper,
 550                             u32 scope, bool exact, struct list_head *dports)
 551 {
 552         struct service_range *sr;
 553         struct tipc_service *sc;
 554         struct publication *p;
 555         struct rb_node *n;
 556
 557         rcu_read_lock();
 558         sc = tipc_service_find(net, type);
 559         if (!sc)
 560                 goto exit;
 561
 562         spin_lock_bh(&sc->lock);
 563
 564         for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
 565                 sr = container_of(n, struct service_range, tree_node);
 566                 if (sr->upper < lower)
 567                         continue;
 568                 if (sr->lower > upper)
 569                         break;
 570                 list_for_each_entry(p, &sr->local_publ, local_publ) {
 571                         if (p->scope == scope || (!exact && p->scope < scope))
 572                                 tipc_dest_push(dports, 0, p->port);
 573                 }
 574         }
 575         spin_unlock_bh(&sc->lock);
 576 exit:
 577         rcu_read_unlock();
 578 }
 579
 580 /* tipc_nametbl_lookup_dst_nodes - find broadcast destination nodes
 581  * - Creates list of nodes that overlap the given multicast address
 582  * - Determines if any node local destinations overlap
 583  */
 584 void tipc_nametbl_lookup_dst_nodes(struct net *net, u32 type, u32 lower,
 585                                    u32 upper, struct tipc_nlist *nodes)
 586 {
 587         struct service_range *sr;
 588         struct tipc_service *sc;
 589         struct publication *p;
 590         struct rb_node *n;
 591
 592         rcu_read_lock();
 593         sc = tipc_service_find(net, type);
 594         if (!sc)
 595                 goto exit;
 596
 597         spin_lock_bh(&sc->lock);
 598
 599         for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
 600                 sr = container_of(n, struct service_range, tree_node);
 601                 if (sr->upper < lower)
 602                         continue;
 603                 if (sr->lower > upper)
 604                         break;
 605                 list_for_each_entry(p, &sr->all_publ, all_publ) {
 606                         tipc_nlist_add(nodes, p->node);
 607                 }
 608         }
 609         spin_unlock_bh(&sc->lock);
 610 exit:
 611         rcu_read_unlock();
 612 }
 613
 614 /* tipc_nametbl_build_group - build list of communication group members
 615  */
 616 void tipc_nametbl_build_group(struct net *net, struct tipc_group *grp,
 617                               u32 type, u32 scope)
 618 {
 619         struct service_range *sr;
 620         struct tipc_service *sc;
 621         struct publication *p;
 622         struct rb_node *n;
 623
 624         rcu_read_lock();
 625         sc = tipc_service_find(net, type);
 626         if (!sc)
 627                 goto exit;
 628
 629         spin_lock_bh(&sc->lock);
 630         for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
 631                 sr = container_of(n, struct service_range, tree_node);
 632                 list_for_each_entry(p, &sr->all_publ, all_publ) {
 633                         if (p->scope != scope)
 634                                 continue;
 635                         tipc_group_add_member(grp, p->node, p->port, p->lower);
 636                 }
 637         }
 638         spin_unlock_bh(&sc->lock);
 639 exit:
 640         rcu_read_unlock();
 641 }
 642
 643 /* tipc_nametbl_publish - add service binding to name table
 644  */
 645 struct publication *tipc_nametbl_publish(struct net *net, u32 type, u32 lower,
 646                                          u32 upper, u32 scope, u32 port,
 647                                          u32 key)
 648 {
 649         struct name_table *nt = tipc_name_table(net);
 650         struct tipc_net *tn = tipc_net(net);
 651         struct publication *p = NULL;
 652         struct sk_buff *skb = NULL;
 653
 654         spin_lock_bh(&tn->nametbl_lock);
 655
 656         if (nt->local_publ_count >= TIPC_MAX_PUBL) {
 657                 pr_warn("Bind failed, max limit %u reached\n", TIPC_MAX_PUBL);
 658                 goto exit;
 659         }
 660
 661         p = tipc_nametbl_insert_publ(net, type, lower, upper, scope,
 662                                      tipc_own_addr(net), port, key);
 663         if (p) {
 664                 nt->local_publ_count++;
 665                 skb = tipc_named_publish(net, p);
 666         }
 667 exit:
 668         spin_unlock_bh(&tn->nametbl_lock);
 669
 670         if (skb)
 671                 tipc_node_broadcast(net, skb);
 672         return p;
 673 }
 674
 675 /**
 676  * tipc_nametbl_withdraw - withdraw a service binding
 677  */
 678 int tipc_nametbl_withdraw(struct net *net, u32 type, u32 lower,
 679                           u32 upper, u32 key)
 680 {
 681         struct name_table *nt = tipc_name_table(net);
 682         struct tipc_net *tn = tipc_net(net);
 683         u32 self = tipc_own_addr(net);
 684         struct sk_buff *skb = NULL;
 685         struct publication *p;
 686
 687         spin_lock_bh(&tn->nametbl_lock);
 688
 689         p = tipc_nametbl_remove_publ(net, type, lower, upper, self, key);
 690         if (p) {
 691                 nt->local_publ_count--;
 692                 skb = tipc_named_withdraw(net, p);
 693                 list_del_init(&p->binding_sock);
 694                 kfree_rcu(p, rcu);
 695         } else {
 696                 pr_err("Failed to remove local publication {%u,%u,%u}/%u\n",
 697                        type, lower, upper, key);
 698         }
 699         spin_unlock_bh(&tn->nametbl_lock);
 700
 701         if (skb) {
 702                 tipc_node_broadcast(net, skb);
 703                 return 1;
 704         }
 705         return 0;
 706 }
 707
 708 /**
 709  * tipc_nametbl_subscribe - add a subscription object to the name table
 710  */
 711 bool tipc_nametbl_subscribe(struct tipc_subscription *sub)
 712 {
 713         struct name_table *nt = tipc_name_table(sub->net);
 714         struct tipc_net *tn = tipc_net(sub->net);
 715         struct tipc_subscr *s = &sub->evt.s;
 716         u32 type = tipc_sub_read(s, seq.type);
 717         struct tipc_service *sc;
 718         bool res = true;
 719
 720         spin_lock_bh(&tn->nametbl_lock);
 721         sc = tipc_service_find(sub->net, type);
 722         if (!sc)
 723                 sc = tipc_service_create(type, &nt->services[hash(type)]);
 724         if (sc) {
 725                 spin_lock_bh(&sc->lock);
 726                 tipc_service_subscribe(sc, sub);
 727                 spin_unlock_bh(&sc->lock);
 728         } else {
 729                 pr_warn("Failed to subscribe for {%u,%u,%u}\n", type,
 730                         tipc_sub_read(s, seq.lower),
 731                         tipc_sub_read(s, seq.upper));
 732                 res = false;
 733         }
 734         spin_unlock_bh(&tn->nametbl_lock);
 735         return res;
 736 }
 737
 738 /**
 739  * tipc_nametbl_unsubscribe - remove a subscription object from name table
 740  */
 741 void tipc_nametbl_unsubscribe(struct tipc_subscription *sub)
 742 {
 743         struct tipc_net *tn = tipc_net(sub->net);
 744         struct tipc_subscr *s = &sub->evt.s;
 745         u32 type = tipc_sub_read(s, seq.type);
 746         struct tipc_service *sc;
 747
 748         spin_lock_bh(&tn->nametbl_lock);
 749         sc = tipc_service_find(sub->net, type);
 750         if (!sc)
 751                 goto exit;
 752
 753         spin_lock_bh(&sc->lock);
 754         list_del_init(&sub->service_list);
 755         tipc_sub_put(sub);
 756
 757         /* Delete service item if no more publications and subscriptions */
 758         if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) {
 759                 hlist_del_init_rcu(&sc->service_list);
 760                 kfree_rcu(sc, rcu);
 761         }
 762         spin_unlock_bh(&sc->lock);
 763 exit:
 764         spin_unlock_bh(&tn->nametbl_lock);
 765 }
 766
 767 int tipc_nametbl_init(struct net *net)
 768 {
 769         struct tipc_net *tn = tipc_net(net);
 770         struct name_table *nt;
 771         int i;
 772
 773         nt = kzalloc(sizeof(*nt), GFP_KERNEL);
 774         if (!nt)
 775                 return -ENOMEM;
 776
 777         for (i = 0; i < TIPC_NAMETBL_SIZE; i++)
 778                 INIT_HLIST_HEAD(&nt->services[i]);
 779
 780         INIT_LIST_HEAD(&nt->node_scope);
 781         INIT_LIST_HEAD(&nt->cluster_scope);
 782         rwlock_init(&nt->cluster_scope_lock);
 783         tn->nametbl = nt;
 784         spin_lock_init(&tn->nametbl_lock);
 785         return 0;
 786 }
 787
 788 /**
 789  *  tipc_service_delete - purge all publications for a service and delete it
 790  */
 791 static void tipc_service_delete(struct net *net, struct tipc_service *sc)
 792 {
 793         struct service_range *sr, *tmpr;
 794         struct publication *p, *tmp;
 795
 796         spin_lock_bh(&sc->lock);
 797         rbtree_postorder_for_each_entry_safe(sr, tmpr, &sc->ranges, tree_node) {
 798                 list_for_each_entry_safe(p, tmp, &sr->all_publ, all_publ) {
 799                         tipc_service_remove_publ(sr, p->node, p->key);
 800                         kfree_rcu(p, rcu);
 801                 }
 802                 rb_erase(&sr->tree_node, &sc->ranges);
 803                 kfree(sr);
 804         }
 805         hlist_del_init_rcu(&sc->service_list);
 806         spin_unlock_bh(&sc->lock);
 807         kfree_rcu(sc, rcu);
 808 }
 809
 810 void tipc_nametbl_stop(struct net *net)
 811 {
 812         struct name_table *nt = tipc_name_table(net);
 813         struct tipc_net *tn = tipc_net(net);
 814         struct hlist_head *service_head;
 815         struct tipc_service *service;
 816         u32 i;
 817
 818         /* Verify name table is empty and purge any lingering
 819          * publications, then release the name table
 820          */
 821         spin_lock_bh(&tn->nametbl_lock);
 822         for (i = 0; i < TIPC_NAMETBL_SIZE; i++) {
 823                 if (hlist_empty(&nt->services[i]))
 824                         continue;
 825                 service_head = &nt->services[i];
 826                 hlist_for_each_entry_rcu(service, service_head, service_list) {
 827                         tipc_service_delete(net, service);
 828                 }
 829         }
 830         spin_unlock_bh(&tn->nametbl_lock);
 831
 832         synchronize_net();
 833         kfree(nt);
 834 }
 835
 836 static int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg,
 837                                         struct tipc_service *service,
 838                                         struct service_range *sr,
 839                                         u32 *last_key)
 840 {
 841         struct publication *p;
 842         struct nlattr *attrs;
 843         struct nlattr *b;
 844         void *hdr;
 845
 846         if (*last_key) {
 847                 list_for_each_entry(p, &sr->all_publ, all_publ)
 848                         if (p->key == *last_key)
 849                                 break;
 850                 if (p->key != *last_key)
 851                         return -EPIPE;
 852         } else {
 853                 p = list_first_entry(&sr->all_publ,
 854                                      struct publication,
 855                                      all_publ);
 856         }
 857
 858         list_for_each_entry_from(p, &sr->all_publ, all_publ) {
 859                 *last_key = p->key;
 860
 861                 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq,
 862                                   &tipc_genl_family, NLM_F_MULTI,
 863                                   TIPC_NL_NAME_TABLE_GET);
 864                 if (!hdr)
 865                         return -EMSGSIZE;
 866
 867                 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE);
 868                 if (!attrs)
 869                         goto msg_full;
 870
 871                 b = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE_PUBL);
 872                 if (!b)
 873                         goto attr_msg_full;
 874
 875                 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, service->type))
 876                         goto publ_msg_full;
 877                 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sr->lower))
 878                         goto publ_msg_full;
 879                 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sr->upper))
 880                         goto publ_msg_full;
 881                 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope))
 882                         goto publ_msg_full;
 883                 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->node))
 884                         goto publ_msg_full;
 885                 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->port))
 886                         goto publ_msg_full;
 887                 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key))
 888                         goto publ_msg_full;
 889
 890                 nla_nest_end(msg->skb, b);
 891                 nla_nest_end(msg->skb, attrs);
 892                 genlmsg_end(msg->skb, hdr);
 893         }
 894         *last_key = 0;
 895
 896         return 0;
 897
 898 publ_msg_full:
 899         nla_nest_cancel(msg->skb, b);
 900 attr_msg_full:
 901         nla_nest_cancel(msg->skb, attrs);
 902 msg_full:
 903         genlmsg_cancel(msg->skb, hdr);
 904
 905         return -EMSGSIZE;
 906 }
 907
 908 static int __tipc_nl_service_range_list(struct tipc_nl_msg *msg,
 909                                         struct tipc_service *sc,
 910                                         u32 *last_lower, u32 *last_key)
 911 {
 912         struct service_range *sr;
 913         struct rb_node *n;
 914         int err;
 915
 916         for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
 917                 sr = container_of(n, struct service_range, tree_node);
 918                 if (sr->lower < *last_lower)
 919                         continue;
 920                 err = __tipc_nl_add_nametable_publ(msg, sc, sr, last_key);
 921                 if (err) {
 922                         *last_lower = sr->lower;
 923                         return err;
 924                 }
 925         }
 926         *last_lower = 0;
 927         return 0;
 928 }
 929
 930 static int tipc_nl_service_list(struct net *net, struct tipc_nl_msg *msg,
 931                                 u32 *last_type, u32 *last_lower, u32 *last_key)
 932 {
 933         struct tipc_net *tn = tipc_net(net);
 934         struct tipc_service *service = NULL;
 935         struct hlist_head *head;
 936         int err;
 937         int i;
 938
 939         if (*last_type)
 940                 i = hash(*last_type);
 941         else
 942                 i = 0;
 943
 944         for (; i < TIPC_NAMETBL_SIZE; i++) {
 945                 head = &tn->nametbl->services[i];
 946
 947                 if (*last_type ||
 948                     (!i && *last_key && (*last_lower == *last_key))) {
 949                         service = tipc_service_find(net, *last_type);
 950                         if (!service)
 951                                 return -EPIPE;
 952                 } else {
 953                         hlist_for_each_entry_rcu(service, head, service_list)
 954                                 break;
 955                         if (!service)
 956                                 continue;
 957                 }
 958
 959                 hlist_for_each_entry_from_rcu(service, service_list) {
 960                         spin_lock_bh(&service->lock);
 961                         err = __tipc_nl_service_range_list(msg, service,
 962                                                            last_lower,
 963                                                            last_key);
 964
 965                         if (err) {
 966                                 *last_type = service->type;
 967                                 spin_unlock_bh(&service->lock);
 968                                 return err;
 969                         }
 970                         spin_unlock_bh(&service->lock);
 971                 }
 972                 *last_type = 0;
 973         }
 974         return 0;
 975 }
 976
 977 int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb)
 978 {
 979         struct net *net = sock_net(skb->sk);
 980         u32 last_type = cb->args[0];
 981         u32 last_lower = cb->args[1];
 982         u32 last_key = cb->args[2];
 983         int done = cb->args[3];
 984         struct tipc_nl_msg msg;
 985         int err;
 986
 987         if (done)
 988                 return 0;
 989
 990         msg.skb = skb;
 991         msg.portid = NETLINK_CB(cb->skb).portid;
 992         msg.seq = cb->nlh->nlmsg_seq;
 993
 994         rcu_read_lock();
 995         err = tipc_nl_service_list(net, &msg, &last_type,
 996                                    &last_lower, &last_key);
 997         if (!err) {
 998                 done = 1;
 999         } else if (err != -EMSGSIZE) {
1000                 /* We never set seq or call nl_dump_check_consistent() this
1001                  * means that setting prev_seq here will cause the consistence
1002                  * check to fail in the netlink callback handler. Resulting in
1003                  * the NLMSG_DONE message having the NLM_F_DUMP_INTR flag set if
1004                  * we got an error.
1005                  */
1006                 cb->prev_seq = 1;
1007         }
1008         rcu_read_unlock();
1009
1010         cb->args[0] = last_type;
1011         cb->args[1] = last_lower;
1012         cb->args[2] = last_key;
1013         cb->args[3] = done;
1014
1015         return skb->len;
1016 }
1017
1018 struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port)
1019 {
1020         struct tipc_dest *dst;
1021
1022         list_for_each_entry(dst, l, list) {
1023                 if (dst->node == node && dst->port == port)
1024                         return dst;
1025         }
1026         return NULL;
1027 }
1028
1029 bool tipc_dest_push(struct list_head *l, u32 node, u32 port)
1030 {
1031         struct tipc_dest *dst;
1032
1033         if (tipc_dest_find(l, node, port))
1034                 return false;
1035
1036         dst = kmalloc(sizeof(*dst), GFP_ATOMIC);
1037         if (unlikely(!dst))
1038                 return false;
1039         dst->node = node;
1040         dst->port = port;
1041         list_add(&dst->list, l);
1042         return true;
1043 }
1044
1045 bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port)
1046 {
1047         struct tipc_dest *dst;
1048
1049         if (list_empty(l))
1050                 return false;
1051         dst = list_first_entry(l, typeof(*dst), list);
1052         if (port)
1053                 *port = dst->port;
1054         if (node)
1055                 *node = dst->node;
1056         list_del(&dst->list);
1057         kfree(dst);
1058         return true;
1059 }
1060
1061 bool tipc_dest_del(struct list_head *l, u32 node, u32 port)
1062 {
1063         struct tipc_dest *dst;
1064
1065         dst = tipc_dest_find(l, node, port);
1066         if (!dst)
1067                 return false;
1068         list_del(&dst->list);
1069         kfree(dst);
1070         return true;
1071 }
1072
1073 void tipc_dest_list_purge(struct list_head *l)
1074 {
1075         struct tipc_dest *dst, *tmp;
1076
1077         list_for_each_entry_safe(dst, tmp, l, list) {
1078                 list_del(&dst->list);
1079                 kfree(dst);
1080         }
1081 }
1082
1083 int tipc_dest_list_len(struct list_head *l)
1084 {
1085         struct tipc_dest *dst;
1086         int i = 0;
1087
1088         list_for_each_entry(dst, l, list) {
1089                 i++;
1090         }
1091         return i;
1092 }