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 * Copyright (c) 2020-2021, Red Hat Inc 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the names of the copyright holders nor the names of its 18 * contributors may be used to endorse or promote products derived from 19 * this software without specific prior written permission. 20 * 21 * Alternatively, this software may be distributed under the terms of the 22 * GNU General Public License ("GPL") version 2 as published by the Free 23 * Software Foundation. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 26 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 29 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 * POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 #include <net/sock.h> 39 #include <linux/list_sort.h> 40 #include <linux/rbtree_augmented.h> 41 #include "core.h" 42 #include "netlink.h" 43 #include "name_table.h" 44 #include "name_distr.h" 45 #include "subscr.h" 46 #include "bcast.h" 47 #include "addr.h" 48 #include "node.h" 49 #include "group.h" 50 51 /** 52 * struct service_range - container for all bindings of a service range 53 * @lower: service range lower bound 54 * @upper: service range upper bound 55 * @tree_node: member of service range RB tree 56 * @max: largest 'upper' in this node subtree 57 * @local_publ: list of identical publications made from this node 58 * Used by closest_first lookup and multicast lookup algorithm 59 * @all_publ: all publications identical to this one, whatever node and scope 60 * Used by round-robin lookup algorithm 61 */ 62 struct service_range { 63 u32 lower; 64 u32 upper; 65 struct rb_node tree_node; 66 u32 max; 67 struct list_head local_publ; 68 struct list_head all_publ; 69 }; 70 71 /** 72 * struct tipc_service - container for all published instances of a service type 73 * @type: 32 bit 'type' value for service 74 * @publ_cnt: increasing counter for publications in this service 75 * @ranges: rb tree containing all service ranges for this service 76 * @service_list: links to adjacent name ranges in hash chain 77 * @subscriptions: list of subscriptions for this service type 78 * @lock: spinlock controlling access to pertaining service ranges/publications 79 * @rcu: RCU callback head used for deferred freeing 80 */ 81 struct tipc_service { 82 u32 type; 83 u32 publ_cnt; 84 struct rb_root ranges; 85 struct hlist_node service_list; 86 struct list_head subscriptions; 87 spinlock_t lock; /* Covers service range list */ 88 struct rcu_head rcu; 89 }; 90 91 #define service_range_upper(sr) ((sr)->upper) 92 RB_DECLARE_CALLBACKS_MAX(static, sr_callbacks, 93 struct service_range, tree_node, u32, max, 94 service_range_upper) 95 96 #define service_range_entry(rbtree_node) \ 97 (container_of(rbtree_node, struct service_range, tree_node)) 98 99 #define service_range_overlap(sr, start, end) \ 100 ((sr)->lower <= (end) && (sr)->upper >= (start)) 101 102 /** 103 * service_range_foreach_match - iterate over tipc service rbtree for each 104 * range match 105 * @sr: the service range pointer as a loop cursor 106 * @sc: the pointer to tipc service which holds the service range rbtree 107 * @start: beginning of the search range (end >= start) for matching 108 * @end: end of the search range (end >= start) for matching 109 */ 110 #define service_range_foreach_match(sr, sc, start, end) \ 111 for (sr = service_range_match_first((sc)->ranges.rb_node, \ 112 start, \ 113 end); \ 114 sr; \ 115 sr = service_range_match_next(&(sr)->tree_node, \ 116 start, \ 117 end)) 118 119 /** 120 * service_range_match_first - find first service range matching a range 121 * @n: the root node of service range rbtree for searching 122 * @start: beginning of the search range (end >= start) for matching 123 * @end: end of the search range (end >= start) for matching 124 * 125 * Return: the leftmost service range node in the rbtree that overlaps the 126 * specific range if any. Otherwise, returns NULL. 127 */ 128 static struct service_range *service_range_match_first(struct rb_node *n, 129 u32 start, u32 end) 130 { 131 struct service_range *sr; 132 struct rb_node *l, *r; 133 134 /* Non overlaps in tree at all? */ 135 if (!n || service_range_entry(n)->max < start) 136 return NULL; 137 138 while (n) { 139 l = n->rb_left; 140 if (l && service_range_entry(l)->max >= start) { 141 /* A leftmost overlap range node must be one in the left 142 * subtree. If not, it has lower > end, then nodes on 143 * the right side cannot satisfy the condition either. 144 */ 145 n = l; 146 continue; 147 } 148 149 /* No one in the left subtree can match, return if this node is 150 * an overlap i.e. leftmost. 151 */ 152 sr = service_range_entry(n); 153 if (service_range_overlap(sr, start, end)) 154 return sr; 155 156 /* Ok, try to lookup on the right side */ 157 r = n->rb_right; 158 if (sr->lower <= end && 159 r && service_range_entry(r)->max >= start) { 160 n = r; 161 continue; 162 } 163 break; 164 } 165 166 return NULL; 167 } 168 169 /** 170 * service_range_match_next - find next service range matching a range 171 * @n: a node in service range rbtree from which the searching starts 172 * @start: beginning of the search range (end >= start) for matching 173 * @end: end of the search range (end >= start) for matching 174 * 175 * Return: the next service range node to the given node in the rbtree that 176 * overlaps the specific range if any. Otherwise, returns NULL. 177 */ 178 static struct service_range *service_range_match_next(struct rb_node *n, 179 u32 start, u32 end) 180 { 181 struct service_range *sr; 182 struct rb_node *p, *r; 183 184 while (n) { 185 r = n->rb_right; 186 if (r && service_range_entry(r)->max >= start) 187 /* A next overlap range node must be one in the right 188 * subtree. If not, it has lower > end, then any next 189 * successor (- an ancestor) of this node cannot 190 * satisfy the condition either. 191 */ 192 return service_range_match_first(r, start, end); 193 194 /* No one in the right subtree can match, go up to find an 195 * ancestor of this node which is parent of a left-hand child. 196 */ 197 while ((p = rb_parent(n)) && n == p->rb_right) 198 n = p; 199 if (!p) 200 break; 201 202 /* Return if this ancestor is an overlap */ 203 sr = service_range_entry(p); 204 if (service_range_overlap(sr, start, end)) 205 return sr; 206 207 /* Ok, try to lookup more from this ancestor */ 208 if (sr->lower <= end) { 209 n = p; 210 continue; 211 } 212 break; 213 } 214 215 return NULL; 216 } 217 218 static int hash(int x) 219 { 220 return x & (TIPC_NAMETBL_SIZE - 1); 221 } 222 223 /** 224 * tipc_publ_create - create a publication structure 225 * @ua: the service range the user is binding to 226 * @sk: the address of the socket that is bound 227 * @key: publication key 228 */ 229 static struct publication *tipc_publ_create(struct tipc_uaddr *ua, 230 struct tipc_socket_addr *sk, 231 u32 key) 232 { 233 struct publication *p = kzalloc(sizeof(*p), GFP_ATOMIC); 234 235 if (!p) 236 return NULL; 237 238 p->sr = ua->sr; 239 p->sk = *sk; 240 p->scope = ua->scope; 241 p->key = key; 242 INIT_LIST_HEAD(&p->binding_sock); 243 INIT_LIST_HEAD(&p->binding_node); 244 INIT_LIST_HEAD(&p->local_publ); 245 INIT_LIST_HEAD(&p->all_publ); 246 INIT_LIST_HEAD(&p->list); 247 return p; 248 } 249 250 /** 251 * tipc_service_create - create a service structure for the specified 'type' 252 * @type: service type 253 * @hd: name_table services list 254 * 255 * Allocates a single range structure and sets it to all 0's. 256 */ 257 static struct tipc_service *tipc_service_create(u32 type, struct hlist_head *hd) 258 { 259 struct tipc_service *service = kzalloc(sizeof(*service), GFP_ATOMIC); 260 261 if (!service) { 262 pr_warn("Service creation failed, no memory\n"); 263 return NULL; 264 } 265 266 spin_lock_init(&service->lock); 267 service->type = type; 268 service->ranges = RB_ROOT; 269 INIT_HLIST_NODE(&service->service_list); 270 INIT_LIST_HEAD(&service->subscriptions); 271 hlist_add_head_rcu(&service->service_list, hd); 272 return service; 273 } 274 275 /* tipc_service_find_range - find service range matching publication parameters 276 */ 277 static struct service_range *tipc_service_find_range(struct tipc_service *sc, 278 u32 lower, u32 upper) 279 { 280 struct service_range *sr; 281 282 service_range_foreach_match(sr, sc, lower, upper) { 283 /* Look for exact match */ 284 if (sr->lower == lower && sr->upper == upper) 285 return sr; 286 } 287 288 return NULL; 289 } 290 291 static struct service_range *tipc_service_create_range(struct tipc_service *sc, 292 u32 lower, u32 upper) 293 { 294 struct rb_node **n, *parent = NULL; 295 struct service_range *sr; 296 297 n = &sc->ranges.rb_node; 298 while (*n) { 299 parent = *n; 300 sr = service_range_entry(parent); 301 if (lower == sr->lower && upper == sr->upper) 302 return sr; 303 if (sr->max < upper) 304 sr->max = upper; 305 if (lower <= sr->lower) 306 n = &parent->rb_left; 307 else 308 n = &parent->rb_right; 309 } 310 sr = kzalloc(sizeof(*sr), GFP_ATOMIC); 311 if (!sr) 312 return NULL; 313 sr->lower = lower; 314 sr->upper = upper; 315 sr->max = upper; 316 INIT_LIST_HEAD(&sr->local_publ); 317 INIT_LIST_HEAD(&sr->all_publ); 318 rb_link_node(&sr->tree_node, parent, n); 319 rb_insert_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks); 320 return sr; 321 } 322 323 static bool tipc_service_insert_publ(struct net *net, 324 struct tipc_service *sc, 325 struct publication *p) 326 { 327 struct tipc_subscription *sub, *tmp; 328 struct service_range *sr; 329 struct publication *_p; 330 u32 node = p->sk.node; 331 bool first = false; 332 bool res = false; 333 334 spin_lock_bh(&sc->lock); 335 sr = tipc_service_create_range(sc, p->sr.lower, p->sr.upper); 336 if (!sr) 337 goto exit; 338 339 first = list_empty(&sr->all_publ); 340 341 /* Return if the publication already exists */ 342 list_for_each_entry(_p, &sr->all_publ, all_publ) { 343 if (_p->key == p->key && (!_p->sk.node || _p->sk.node == node)) 344 goto exit; 345 } 346 347 if (in_own_node(net, p->sk.node)) 348 list_add(&p->local_publ, &sr->local_publ); 349 list_add(&p->all_publ, &sr->all_publ); 350 p->id = sc->publ_cnt++; 351 352 /* Any subscriptions waiting for notification? */ 353 list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) { 354 tipc_sub_report_overlap(sub, p->sr.lower, p->sr.upper, 355 TIPC_PUBLISHED, p->sk.ref, p->sk.node, 356 p->scope, first); 357 } 358 res = true; 359 exit: 360 if (!res) 361 pr_warn("Failed to bind to %u,%u,%u\n", 362 p->sr.type, p->sr.lower, p->sr.upper); 363 spin_unlock_bh(&sc->lock); 364 return res; 365 } 366 367 /** 368 * tipc_service_remove_publ - remove a publication from a service 369 * @r: service_range to remove publication from 370 * @sk: address publishing socket 371 * @key: target publication key 372 */ 373 static struct publication *tipc_service_remove_publ(struct service_range *r, 374 struct tipc_socket_addr *sk, 375 u32 key) 376 { 377 struct publication *p; 378 u32 node = sk->node; 379 380 list_for_each_entry(p, &r->all_publ, all_publ) { 381 if (p->key != key || (node && node != p->sk.node)) 382 continue; 383 list_del(&p->all_publ); 384 list_del(&p->local_publ); 385 return p; 386 } 387 return NULL; 388 } 389 390 /* 391 * Code reused: time_after32() for the same purpose 392 */ 393 #define publication_after(pa, pb) time_after32((pa)->id, (pb)->id) 394 static int tipc_publ_sort(void *priv, struct list_head *a, 395 struct list_head *b) 396 { 397 struct publication *pa, *pb; 398 399 pa = container_of(a, struct publication, list); 400 pb = container_of(b, struct publication, list); 401 return publication_after(pa, pb); 402 } 403 404 /** 405 * tipc_service_subscribe - attach a subscription, and optionally 406 * issue the prescribed number of events if there is any service 407 * range overlapping with the requested range 408 * @service: the tipc_service to attach the @sub to 409 * @sub: the subscription to attach 410 */ 411 static void tipc_service_subscribe(struct tipc_service *service, 412 struct tipc_subscription *sub) 413 { 414 struct tipc_subscr *sb = &sub->evt.s; 415 struct publication *p, *first, *tmp; 416 struct list_head publ_list; 417 struct service_range *sr; 418 struct tipc_service_range r; 419 u32 filter; 420 421 r.type = tipc_sub_read(sb, seq.type); 422 r.lower = tipc_sub_read(sb, seq.lower); 423 r.upper = tipc_sub_read(sb, seq.upper); 424 filter = tipc_sub_read(sb, filter); 425 426 tipc_sub_get(sub); 427 list_add(&sub->service_list, &service->subscriptions); 428 429 if (filter & TIPC_SUB_NO_STATUS) 430 return; 431 432 INIT_LIST_HEAD(&publ_list); 433 service_range_foreach_match(sr, service, r.lower, r.upper) { 434 first = NULL; 435 list_for_each_entry(p, &sr->all_publ, all_publ) { 436 if (filter & TIPC_SUB_PORTS) 437 list_add_tail(&p->list, &publ_list); 438 else if (!first || publication_after(first, p)) 439 /* Pick this range's *first* publication */ 440 first = p; 441 } 442 if (first) 443 list_add_tail(&first->list, &publ_list); 444 } 445 446 /* Sort the publications before reporting */ 447 list_sort(NULL, &publ_list, tipc_publ_sort); 448 list_for_each_entry_safe(p, tmp, &publ_list, list) { 449 tipc_sub_report_overlap(sub, p->sr.lower, p->sr.upper, 450 TIPC_PUBLISHED, p->sk.ref, p->sk.node, 451 p->scope, true); 452 list_del_init(&p->list); 453 } 454 } 455 456 static struct tipc_service *tipc_service_find(struct net *net, u32 type) 457 { 458 struct name_table *nt = tipc_name_table(net); 459 struct hlist_head *service_head; 460 struct tipc_service *service; 461 462 service_head = &nt->services[hash(type)]; 463 hlist_for_each_entry_rcu(service, service_head, service_list) { 464 if (service->type == type) 465 return service; 466 } 467 return NULL; 468 }; 469 470 struct publication *tipc_nametbl_insert_publ(struct net *net, 471 struct tipc_uaddr *ua, 472 struct tipc_socket_addr *sk, 473 u32 key) 474 { 475 struct name_table *nt = tipc_name_table(net); 476 struct tipc_service *sc; 477 struct publication *p; 478 u32 type = ua->sr.type; 479 480 p = tipc_publ_create(ua, sk, key); 481 if (!p) 482 return NULL; 483 484 if (ua->sr.lower > ua->sr.upper) { 485 pr_debug("Failed to bind illegal {%u,%u,%u} from node %u\n", 486 type, ua->sr.lower, ua->sr.upper, sk->node); 487 return NULL; 488 } 489 sc = tipc_service_find(net, type); 490 if (!sc) 491 sc = tipc_service_create(type, &nt->services[hash(type)]); 492 if (sc && tipc_service_insert_publ(net, sc, p)) 493 return p; 494 kfree(p); 495 return NULL; 496 } 497 498 struct publication *tipc_nametbl_remove_publ(struct net *net, 499 struct tipc_uaddr *ua, 500 struct tipc_socket_addr *sk, 501 u32 key) 502 { 503 struct tipc_subscription *sub, *tmp; 504 struct publication *p = NULL; 505 struct service_range *sr; 506 struct tipc_service *sc; 507 u32 upper = ua->sr.upper; 508 u32 lower = ua->sr.lower; 509 bool last; 510 511 sc = tipc_service_find(net, ua->sr.type); 512 if (!sc) 513 return NULL; 514 515 spin_lock_bh(&sc->lock); 516 sr = tipc_service_find_range(sc, lower, upper); 517 if (!sr) 518 goto exit; 519 p = tipc_service_remove_publ(sr, sk, key); 520 if (!p) 521 goto exit; 522 523 /* Notify any waiting subscriptions */ 524 last = list_empty(&sr->all_publ); 525 list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) { 526 tipc_sub_report_overlap(sub, lower, upper, TIPC_WITHDRAWN, 527 sk->ref, sk->node, ua->scope, last); 528 } 529 530 /* Remove service range item if this was its last publication */ 531 if (list_empty(&sr->all_publ)) { 532 rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks); 533 kfree(sr); 534 } 535 536 /* Delete service item if this no more publications and subscriptions */ 537 if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) { 538 hlist_del_init_rcu(&sc->service_list); 539 kfree_rcu(sc, rcu); 540 } 541 exit: 542 spin_unlock_bh(&sc->lock); 543 return p; 544 } 545 546 /** 547 * tipc_nametbl_lookup_anycast - perform service instance to socket translation 548 * @net: network namespace 549 * @type: message type 550 * @instance: message instance 551 * @dnode: the search domain used during translation 552 * 553 * On entry, 'dnode' is the search domain used during the lookup 554 * 555 * On exit: 556 * - if lookup is deferred to another node, leave 'dnode' unchanged and return 0 557 * - if lookup is attempted and succeeds, set 'dnode' to the publishing node and 558 * return the published (non-zero) port number 559 * - if lookup is attempted and fails, set 'dnode' to 0 and return 0 560 * 561 * Note that for legacy users (node configured with Z.C.N address format) the 562 * 'closest-first' lookup algorithm must be maintained, i.e., if dnode is 0 563 * we must look in the local binding list first 564 */ 565 u32 tipc_nametbl_lookup_anycast(struct net *net, u32 type, 566 u32 instance, u32 *dnode) 567 { 568 struct tipc_net *tn = tipc_net(net); 569 bool legacy = tn->legacy_addr_format; 570 u32 self = tipc_own_addr(net); 571 struct service_range *sr; 572 struct tipc_service *sc; 573 struct list_head *list; 574 struct publication *p; 575 u32 port = 0; 576 u32 node = 0; 577 578 if (!tipc_in_scope(legacy, *dnode, self)) 579 return 0; 580 581 rcu_read_lock(); 582 sc = tipc_service_find(net, type); 583 if (unlikely(!sc)) 584 goto exit; 585 586 spin_lock_bh(&sc->lock); 587 service_range_foreach_match(sr, sc, instance, instance) { 588 /* Select lookup algo: local, closest-first or round-robin */ 589 if (*dnode == self) { 590 list = &sr->local_publ; 591 if (list_empty(list)) 592 continue; 593 p = list_first_entry(list, struct publication, 594 local_publ); 595 list_move_tail(&p->local_publ, &sr->local_publ); 596 } else if (legacy && !*dnode && !list_empty(&sr->local_publ)) { 597 list = &sr->local_publ; 598 p = list_first_entry(list, struct publication, 599 local_publ); 600 list_move_tail(&p->local_publ, &sr->local_publ); 601 } else { 602 list = &sr->all_publ; 603 p = list_first_entry(list, struct publication, 604 all_publ); 605 list_move_tail(&p->all_publ, &sr->all_publ); 606 } 607 port = p->sk.ref; 608 node = p->sk.node; 609 /* Todo: as for legacy, pick the first matching range only, a 610 * "true" round-robin will be performed as needed. 611 */ 612 break; 613 } 614 spin_unlock_bh(&sc->lock); 615 616 exit: 617 rcu_read_unlock(); 618 *dnode = node; 619 return port; 620 } 621 622 /* tipc_nametbl_lookup_group(): lookup destinaton(s) in a communication group 623 * Returns a list of one (== group anycast) or more (== group multicast) 624 * destination socket/node pairs matching the given address. 625 * The requester may or may not want to exclude himself from the list. 626 */ 627 bool tipc_nametbl_lookup_group(struct net *net, u32 type, u32 instance, 628 u32 scope, struct list_head *dsts, 629 int *dstcnt, u32 exclude, 630 bool mcast) 631 { 632 u32 self = tipc_own_addr(net); 633 struct service_range *sr; 634 struct tipc_service *sc; 635 struct publication *p; 636 637 *dstcnt = 0; 638 rcu_read_lock(); 639 sc = tipc_service_find(net, type); 640 if (unlikely(!sc)) 641 goto exit; 642 643 spin_lock_bh(&sc->lock); 644 645 /* Todo: a full search i.e. service_range_foreach_match() instead? */ 646 sr = service_range_match_first(sc->ranges.rb_node, instance, instance); 647 if (!sr) 648 goto no_match; 649 650 list_for_each_entry(p, &sr->all_publ, all_publ) { 651 if (p->scope != scope) 652 continue; 653 if (p->sk.ref == exclude && p->sk.node == self) 654 continue; 655 tipc_dest_push(dsts, p->sk.node, p->sk.ref); 656 (*dstcnt)++; 657 if (mcast) 658 continue; 659 list_move_tail(&p->all_publ, &sr->all_publ); 660 break; 661 } 662 no_match: 663 spin_unlock_bh(&sc->lock); 664 exit: 665 rcu_read_unlock(); 666 return !list_empty(dsts); 667 } 668 669 /* tipc_nametbl_lookup_mcast_sockets(): look up node local destinaton sockets 670 * matching the given address 671 * Used on nodes which have received a multicast/broadcast message 672 * Returns a list of local sockets 673 */ 674 void tipc_nametbl_lookup_mcast_sockets(struct net *net, u32 type, u32 lower, 675 u32 upper, u32 scope, bool exact, 676 struct list_head *dports) 677 { 678 struct service_range *sr; 679 struct tipc_service *sc; 680 struct publication *p; 681 682 rcu_read_lock(); 683 sc = tipc_service_find(net, type); 684 if (!sc) 685 goto exit; 686 687 spin_lock_bh(&sc->lock); 688 service_range_foreach_match(sr, sc, lower, upper) { 689 list_for_each_entry(p, &sr->local_publ, local_publ) { 690 if (p->scope == scope || (!exact && p->scope < scope)) 691 tipc_dest_push(dports, 0, p->sk.ref); 692 } 693 } 694 spin_unlock_bh(&sc->lock); 695 exit: 696 rcu_read_unlock(); 697 } 698 699 /* tipc_nametbl_lookup_mcast_nodes(): look up all destination nodes matching 700 * the given address. Used in sending node. 701 * Used on nodes which are sending out a multicast/broadcast message 702 * Returns a list of nodes, including own node if applicable 703 */ 704 void tipc_nametbl_lookup_mcast_nodes(struct net *net, u32 type, u32 lower, 705 u32 upper, struct tipc_nlist *nodes) 706 { 707 struct service_range *sr; 708 struct tipc_service *sc; 709 struct publication *p; 710 711 rcu_read_lock(); 712 sc = tipc_service_find(net, type); 713 if (!sc) 714 goto exit; 715 716 spin_lock_bh(&sc->lock); 717 service_range_foreach_match(sr, sc, lower, upper) { 718 list_for_each_entry(p, &sr->all_publ, all_publ) { 719 tipc_nlist_add(nodes, p->sk.node); 720 } 721 } 722 spin_unlock_bh(&sc->lock); 723 exit: 724 rcu_read_unlock(); 725 } 726 727 /* tipc_nametbl_build_group - build list of communication group members 728 */ 729 void tipc_nametbl_build_group(struct net *net, struct tipc_group *grp, 730 u32 type, u32 scope) 731 { 732 struct service_range *sr; 733 struct tipc_service *sc; 734 struct publication *p; 735 struct rb_node *n; 736 737 rcu_read_lock(); 738 sc = tipc_service_find(net, type); 739 if (!sc) 740 goto exit; 741 742 spin_lock_bh(&sc->lock); 743 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) { 744 sr = container_of(n, struct service_range, tree_node); 745 list_for_each_entry(p, &sr->all_publ, all_publ) { 746 if (p->scope != scope) 747 continue; 748 tipc_group_add_member(grp, p->sk.node, p->sk.ref, p->sr.lower); 749 } 750 } 751 spin_unlock_bh(&sc->lock); 752 exit: 753 rcu_read_unlock(); 754 } 755 756 /* tipc_nametbl_publish - add service binding to name table 757 */ 758 struct publication *tipc_nametbl_publish(struct net *net, struct tipc_uaddr *ua, 759 struct tipc_socket_addr *sk, u32 key) 760 { 761 struct name_table *nt = tipc_name_table(net); 762 struct tipc_net *tn = tipc_net(net); 763 struct publication *p = NULL; 764 struct sk_buff *skb = NULL; 765 u32 rc_dests; 766 767 spin_lock_bh(&tn->nametbl_lock); 768 769 if (nt->local_publ_count >= TIPC_MAX_PUBL) { 770 pr_warn("Bind failed, max limit %u reached\n", TIPC_MAX_PUBL); 771 goto exit; 772 } 773 774 p = tipc_nametbl_insert_publ(net, ua, sk, key); 775 if (p) { 776 nt->local_publ_count++; 777 skb = tipc_named_publish(net, p); 778 } 779 rc_dests = nt->rc_dests; 780 exit: 781 spin_unlock_bh(&tn->nametbl_lock); 782 783 if (skb) 784 tipc_node_broadcast(net, skb, rc_dests); 785 return p; 786 787 } 788 789 /** 790 * tipc_nametbl_withdraw - withdraw a service binding 791 * @net: network namespace 792 * @ua: service address/range being unbound 793 * @sk: address of the socket being unbound from 794 * @key: target publication key 795 */ 796 void tipc_nametbl_withdraw(struct net *net, struct tipc_uaddr *ua, 797 struct tipc_socket_addr *sk, u32 key) 798 { 799 struct name_table *nt = tipc_name_table(net); 800 struct tipc_net *tn = tipc_net(net); 801 struct sk_buff *skb = NULL; 802 struct publication *p; 803 u32 rc_dests; 804 805 spin_lock_bh(&tn->nametbl_lock); 806 807 p = tipc_nametbl_remove_publ(net, ua, sk, key); 808 if (p) { 809 nt->local_publ_count--; 810 skb = tipc_named_withdraw(net, p); 811 list_del_init(&p->binding_sock); 812 kfree_rcu(p, rcu); 813 } else { 814 pr_err("Failed to remove local publication {%u,%u,%u}/%u\n", 815 ua->sr.type, ua->sr.lower, ua->sr.upper, key); 816 } 817 rc_dests = nt->rc_dests; 818 spin_unlock_bh(&tn->nametbl_lock); 819 820 if (skb) 821 tipc_node_broadcast(net, skb, rc_dests); 822 } 823 824 /** 825 * tipc_nametbl_subscribe - add a subscription object to the name table 826 * @sub: subscription to add 827 */ 828 bool tipc_nametbl_subscribe(struct tipc_subscription *sub) 829 { 830 struct name_table *nt = tipc_name_table(sub->net); 831 struct tipc_net *tn = tipc_net(sub->net); 832 struct tipc_subscr *s = &sub->evt.s; 833 u32 type = tipc_sub_read(s, seq.type); 834 struct tipc_service *sc; 835 bool res = true; 836 837 spin_lock_bh(&tn->nametbl_lock); 838 sc = tipc_service_find(sub->net, type); 839 if (!sc) 840 sc = tipc_service_create(type, &nt->services[hash(type)]); 841 if (sc) { 842 spin_lock_bh(&sc->lock); 843 tipc_service_subscribe(sc, sub); 844 spin_unlock_bh(&sc->lock); 845 } else { 846 pr_warn("Failed to subscribe for {%u,%u,%u}\n", type, 847 tipc_sub_read(s, seq.lower), 848 tipc_sub_read(s, seq.upper)); 849 res = false; 850 } 851 spin_unlock_bh(&tn->nametbl_lock); 852 return res; 853 } 854 855 /** 856 * tipc_nametbl_unsubscribe - remove a subscription object from name table 857 * @sub: subscription to remove 858 */ 859 void tipc_nametbl_unsubscribe(struct tipc_subscription *sub) 860 { 861 struct tipc_net *tn = tipc_net(sub->net); 862 struct tipc_subscr *s = &sub->evt.s; 863 u32 type = tipc_sub_read(s, seq.type); 864 struct tipc_service *sc; 865 866 spin_lock_bh(&tn->nametbl_lock); 867 sc = tipc_service_find(sub->net, type); 868 if (!sc) 869 goto exit; 870 871 spin_lock_bh(&sc->lock); 872 list_del_init(&sub->service_list); 873 tipc_sub_put(sub); 874 875 /* Delete service item if no more publications and subscriptions */ 876 if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) { 877 hlist_del_init_rcu(&sc->service_list); 878 kfree_rcu(sc, rcu); 879 } 880 spin_unlock_bh(&sc->lock); 881 exit: 882 spin_unlock_bh(&tn->nametbl_lock); 883 } 884 885 int tipc_nametbl_init(struct net *net) 886 { 887 struct tipc_net *tn = tipc_net(net); 888 struct name_table *nt; 889 int i; 890 891 nt = kzalloc(sizeof(*nt), GFP_KERNEL); 892 if (!nt) 893 return -ENOMEM; 894 895 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) 896 INIT_HLIST_HEAD(&nt->services[i]); 897 898 INIT_LIST_HEAD(&nt->node_scope); 899 INIT_LIST_HEAD(&nt->cluster_scope); 900 rwlock_init(&nt->cluster_scope_lock); 901 tn->nametbl = nt; 902 spin_lock_init(&tn->nametbl_lock); 903 return 0; 904 } 905 906 /** 907 * tipc_service_delete - purge all publications for a service and delete it 908 * @net: the associated network namespace 909 * @sc: tipc_service to delete 910 */ 911 static void tipc_service_delete(struct net *net, struct tipc_service *sc) 912 { 913 struct service_range *sr, *tmpr; 914 struct publication *p, *tmp; 915 916 spin_lock_bh(&sc->lock); 917 rbtree_postorder_for_each_entry_safe(sr, tmpr, &sc->ranges, tree_node) { 918 list_for_each_entry_safe(p, tmp, &sr->all_publ, all_publ) { 919 tipc_service_remove_publ(sr, &p->sk, p->key); 920 kfree_rcu(p, rcu); 921 } 922 rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks); 923 kfree(sr); 924 } 925 hlist_del_init_rcu(&sc->service_list); 926 spin_unlock_bh(&sc->lock); 927 kfree_rcu(sc, rcu); 928 } 929 930 void tipc_nametbl_stop(struct net *net) 931 { 932 struct name_table *nt = tipc_name_table(net); 933 struct tipc_net *tn = tipc_net(net); 934 struct hlist_head *service_head; 935 struct tipc_service *service; 936 u32 i; 937 938 /* Verify name table is empty and purge any lingering 939 * publications, then release the name table 940 */ 941 spin_lock_bh(&tn->nametbl_lock); 942 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) { 943 if (hlist_empty(&nt->services[i])) 944 continue; 945 service_head = &nt->services[i]; 946 hlist_for_each_entry_rcu(service, service_head, service_list) { 947 tipc_service_delete(net, service); 948 } 949 } 950 spin_unlock_bh(&tn->nametbl_lock); 951 952 synchronize_net(); 953 kfree(nt); 954 } 955 956 static int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg, 957 struct tipc_service *service, 958 struct service_range *sr, 959 u32 *last_key) 960 { 961 struct publication *p; 962 struct nlattr *attrs; 963 struct nlattr *b; 964 void *hdr; 965 966 if (*last_key) { 967 list_for_each_entry(p, &sr->all_publ, all_publ) 968 if (p->key == *last_key) 969 break; 970 if (p->key != *last_key) 971 return -EPIPE; 972 } else { 973 p = list_first_entry(&sr->all_publ, 974 struct publication, 975 all_publ); 976 } 977 978 list_for_each_entry_from(p, &sr->all_publ, all_publ) { 979 *last_key = p->key; 980 981 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, 982 &tipc_genl_family, NLM_F_MULTI, 983 TIPC_NL_NAME_TABLE_GET); 984 if (!hdr) 985 return -EMSGSIZE; 986 987 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE); 988 if (!attrs) 989 goto msg_full; 990 991 b = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE_PUBL); 992 if (!b) 993 goto attr_msg_full; 994 995 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, service->type)) 996 goto publ_msg_full; 997 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sr->lower)) 998 goto publ_msg_full; 999 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sr->upper)) 1000 goto publ_msg_full; 1001 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope)) 1002 goto publ_msg_full; 1003 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->sk.node)) 1004 goto publ_msg_full; 1005 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->sk.ref)) 1006 goto publ_msg_full; 1007 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key)) 1008 goto publ_msg_full; 1009 1010 nla_nest_end(msg->skb, b); 1011 nla_nest_end(msg->skb, attrs); 1012 genlmsg_end(msg->skb, hdr); 1013 } 1014 *last_key = 0; 1015 1016 return 0; 1017 1018 publ_msg_full: 1019 nla_nest_cancel(msg->skb, b); 1020 attr_msg_full: 1021 nla_nest_cancel(msg->skb, attrs); 1022 msg_full: 1023 genlmsg_cancel(msg->skb, hdr); 1024 1025 return -EMSGSIZE; 1026 } 1027 1028 static int __tipc_nl_service_range_list(struct tipc_nl_msg *msg, 1029 struct tipc_service *sc, 1030 u32 *last_lower, u32 *last_key) 1031 { 1032 struct service_range *sr; 1033 struct rb_node *n; 1034 int err; 1035 1036 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) { 1037 sr = container_of(n, struct service_range, tree_node); 1038 if (sr->lower < *last_lower) 1039 continue; 1040 err = __tipc_nl_add_nametable_publ(msg, sc, sr, last_key); 1041 if (err) { 1042 *last_lower = sr->lower; 1043 return err; 1044 } 1045 } 1046 *last_lower = 0; 1047 return 0; 1048 } 1049 1050 static int tipc_nl_service_list(struct net *net, struct tipc_nl_msg *msg, 1051 u32 *last_type, u32 *last_lower, u32 *last_key) 1052 { 1053 struct tipc_net *tn = tipc_net(net); 1054 struct tipc_service *service = NULL; 1055 struct hlist_head *head; 1056 int err; 1057 int i; 1058 1059 if (*last_type) 1060 i = hash(*last_type); 1061 else 1062 i = 0; 1063 1064 for (; i < TIPC_NAMETBL_SIZE; i++) { 1065 head = &tn->nametbl->services[i]; 1066 1067 if (*last_type || 1068 (!i && *last_key && (*last_lower == *last_key))) { 1069 service = tipc_service_find(net, *last_type); 1070 if (!service) 1071 return -EPIPE; 1072 } else { 1073 hlist_for_each_entry_rcu(service, head, service_list) 1074 break; 1075 if (!service) 1076 continue; 1077 } 1078 1079 hlist_for_each_entry_from_rcu(service, service_list) { 1080 spin_lock_bh(&service->lock); 1081 err = __tipc_nl_service_range_list(msg, service, 1082 last_lower, 1083 last_key); 1084 1085 if (err) { 1086 *last_type = service->type; 1087 spin_unlock_bh(&service->lock); 1088 return err; 1089 } 1090 spin_unlock_bh(&service->lock); 1091 } 1092 *last_type = 0; 1093 } 1094 return 0; 1095 } 1096 1097 int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb) 1098 { 1099 struct net *net = sock_net(skb->sk); 1100 u32 last_type = cb->args[0]; 1101 u32 last_lower = cb->args[1]; 1102 u32 last_key = cb->args[2]; 1103 int done = cb->args[3]; 1104 struct tipc_nl_msg msg; 1105 int err; 1106 1107 if (done) 1108 return 0; 1109 1110 msg.skb = skb; 1111 msg.portid = NETLINK_CB(cb->skb).portid; 1112 msg.seq = cb->nlh->nlmsg_seq; 1113 1114 rcu_read_lock(); 1115 err = tipc_nl_service_list(net, &msg, &last_type, 1116 &last_lower, &last_key); 1117 if (!err) { 1118 done = 1; 1119 } else if (err != -EMSGSIZE) { 1120 /* We never set seq or call nl_dump_check_consistent() this 1121 * means that setting prev_seq here will cause the consistence 1122 * check to fail in the netlink callback handler. Resulting in 1123 * the NLMSG_DONE message having the NLM_F_DUMP_INTR flag set if 1124 * we got an error. 1125 */ 1126 cb->prev_seq = 1; 1127 } 1128 rcu_read_unlock(); 1129 1130 cb->args[0] = last_type; 1131 cb->args[1] = last_lower; 1132 cb->args[2] = last_key; 1133 cb->args[3] = done; 1134 1135 return skb->len; 1136 } 1137 1138 struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port) 1139 { 1140 struct tipc_dest *dst; 1141 1142 list_for_each_entry(dst, l, list) { 1143 if (dst->node == node && dst->port == port) 1144 return dst; 1145 } 1146 return NULL; 1147 } 1148 1149 bool tipc_dest_push(struct list_head *l, u32 node, u32 port) 1150 { 1151 struct tipc_dest *dst; 1152 1153 if (tipc_dest_find(l, node, port)) 1154 return false; 1155 1156 dst = kmalloc(sizeof(*dst), GFP_ATOMIC); 1157 if (unlikely(!dst)) 1158 return false; 1159 dst->node = node; 1160 dst->port = port; 1161 list_add(&dst->list, l); 1162 return true; 1163 } 1164 1165 bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port) 1166 { 1167 struct tipc_dest *dst; 1168 1169 if (list_empty(l)) 1170 return false; 1171 dst = list_first_entry(l, typeof(*dst), list); 1172 if (port) 1173 *port = dst->port; 1174 if (node) 1175 *node = dst->node; 1176 list_del(&dst->list); 1177 kfree(dst); 1178 return true; 1179 } 1180 1181 bool tipc_dest_del(struct list_head *l, u32 node, u32 port) 1182 { 1183 struct tipc_dest *dst; 1184 1185 dst = tipc_dest_find(l, node, port); 1186 if (!dst) 1187 return false; 1188 list_del(&dst->list); 1189 kfree(dst); 1190 return true; 1191 } 1192 1193 void tipc_dest_list_purge(struct list_head *l) 1194 { 1195 struct tipc_dest *dst, *tmp; 1196 1197 list_for_each_entry_safe(dst, tmp, l, list) { 1198 list_del(&dst->list); 1199 kfree(dst); 1200 } 1201 } 1202 1203 int tipc_dest_list_len(struct list_head *l) 1204 { 1205 struct tipc_dest *dst; 1206 int i = 0; 1207 1208 list_for_each_entry(dst, l, list) { 1209 i++; 1210 } 1211 return i; 1212 } 1213