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 * @type: name sequence type 226 * @lower: name sequence lower bound 227 * @upper: name sequence upper bound 228 * @scope: publication scope 229 * @node: network address of publishing socket 230 * @port: publishing port 231 * @key: publication key 232 */ 233 static struct publication *tipc_publ_create(u32 type, u32 lower, u32 upper, 234 u32 scope, u32 node, u32 port, 235 u32 key) 236 { 237 struct publication *p = kzalloc(sizeof(*p), GFP_ATOMIC); 238 239 if (!p) 240 return NULL; 241 242 p->sr.type = type; 243 p->sr.lower = lower; 244 p->sr.upper = upper; 245 p->scope = scope; 246 p->sk.node = node; 247 p->sk.ref = port; 248 p->key = key; 249 INIT_LIST_HEAD(&p->binding_sock); 250 INIT_LIST_HEAD(&p->binding_node); 251 INIT_LIST_HEAD(&p->local_publ); 252 INIT_LIST_HEAD(&p->all_publ); 253 INIT_LIST_HEAD(&p->list); 254 return p; 255 } 256 257 /** 258 * tipc_service_create - create a service structure for the specified 'type' 259 * @type: service type 260 * @hd: name_table services list 261 * 262 * Allocates a single range structure and sets it to all 0's. 263 */ 264 static struct tipc_service *tipc_service_create(u32 type, struct hlist_head *hd) 265 { 266 struct tipc_service *service = kzalloc(sizeof(*service), GFP_ATOMIC); 267 268 if (!service) { 269 pr_warn("Service creation failed, no memory\n"); 270 return NULL; 271 } 272 273 spin_lock_init(&service->lock); 274 service->type = type; 275 service->ranges = RB_ROOT; 276 INIT_HLIST_NODE(&service->service_list); 277 INIT_LIST_HEAD(&service->subscriptions); 278 hlist_add_head_rcu(&service->service_list, hd); 279 return service; 280 } 281 282 /* tipc_service_find_range - find service range matching publication parameters 283 */ 284 static struct service_range *tipc_service_find_range(struct tipc_service *sc, 285 u32 lower, u32 upper) 286 { 287 struct service_range *sr; 288 289 service_range_foreach_match(sr, sc, lower, upper) { 290 /* Look for exact match */ 291 if (sr->lower == lower && sr->upper == upper) 292 return sr; 293 } 294 295 return NULL; 296 } 297 298 static struct service_range *tipc_service_create_range(struct tipc_service *sc, 299 u32 lower, u32 upper) 300 { 301 struct rb_node **n, *parent = NULL; 302 struct service_range *sr; 303 304 n = &sc->ranges.rb_node; 305 while (*n) { 306 parent = *n; 307 sr = service_range_entry(parent); 308 if (lower == sr->lower && upper == sr->upper) 309 return sr; 310 if (sr->max < upper) 311 sr->max = upper; 312 if (lower <= sr->lower) 313 n = &parent->rb_left; 314 else 315 n = &parent->rb_right; 316 } 317 sr = kzalloc(sizeof(*sr), GFP_ATOMIC); 318 if (!sr) 319 return NULL; 320 sr->lower = lower; 321 sr->upper = upper; 322 sr->max = upper; 323 INIT_LIST_HEAD(&sr->local_publ); 324 INIT_LIST_HEAD(&sr->all_publ); 325 rb_link_node(&sr->tree_node, parent, n); 326 rb_insert_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks); 327 return sr; 328 } 329 330 static bool tipc_service_insert_publ(struct net *net, 331 struct tipc_service *sc, 332 struct publication *p) 333 { 334 struct tipc_subscription *sub, *tmp; 335 struct service_range *sr; 336 struct publication *_p; 337 u32 node = p->sk.node; 338 bool first = false; 339 bool res = false; 340 341 spin_lock_bh(&sc->lock); 342 sr = tipc_service_create_range(sc, p->sr.lower, p->sr.upper); 343 if (!sr) 344 goto exit; 345 346 first = list_empty(&sr->all_publ); 347 348 /* Return if the publication already exists */ 349 list_for_each_entry(_p, &sr->all_publ, all_publ) { 350 if (_p->key == p->key && (!_p->sk.node || _p->sk.node == node)) 351 goto exit; 352 } 353 354 if (in_own_node(net, p->sk.node)) 355 list_add(&p->local_publ, &sr->local_publ); 356 list_add(&p->all_publ, &sr->all_publ); 357 p->id = sc->publ_cnt++; 358 359 /* Any subscriptions waiting for notification? */ 360 list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) { 361 tipc_sub_report_overlap(sub, p->sr.lower, p->sr.upper, 362 TIPC_PUBLISHED, p->sk.ref, p->sk.node, 363 p->scope, first); 364 } 365 res = true; 366 exit: 367 if (!res) 368 pr_warn("Failed to bind to %u,%u,%u\n", 369 p->sr.type, p->sr.lower, p->sr.upper); 370 spin_unlock_bh(&sc->lock); 371 return res; 372 } 373 374 /** 375 * tipc_service_remove_publ - remove a publication from a service 376 * @sr: service_range to remove publication from 377 * @node: target node 378 * @key: target publication key 379 */ 380 static struct publication *tipc_service_remove_publ(struct service_range *sr, 381 u32 node, u32 key) 382 { 383 struct publication *p; 384 385 list_for_each_entry(p, &sr->all_publ, all_publ) { 386 if (p->key != key || (node && node != p->sk.node)) 387 continue; 388 list_del(&p->all_publ); 389 list_del(&p->local_publ); 390 return p; 391 } 392 return NULL; 393 } 394 395 /* 396 * Code reused: time_after32() for the same purpose 397 */ 398 #define publication_after(pa, pb) time_after32((pa)->id, (pb)->id) 399 static int tipc_publ_sort(void *priv, struct list_head *a, 400 struct list_head *b) 401 { 402 struct publication *pa, *pb; 403 404 pa = container_of(a, struct publication, list); 405 pb = container_of(b, struct publication, list); 406 return publication_after(pa, pb); 407 } 408 409 /** 410 * tipc_service_subscribe - attach a subscription, and optionally 411 * issue the prescribed number of events if there is any service 412 * range overlapping with the requested range 413 * @service: the tipc_service to attach the @sub to 414 * @sub: the subscription to attach 415 */ 416 static void tipc_service_subscribe(struct tipc_service *service, 417 struct tipc_subscription *sub) 418 { 419 struct tipc_subscr *sb = &sub->evt.s; 420 struct publication *p, *first, *tmp; 421 struct list_head publ_list; 422 struct service_range *sr; 423 struct tipc_service_range r; 424 u32 filter; 425 426 r.type = tipc_sub_read(sb, seq.type); 427 r.lower = tipc_sub_read(sb, seq.lower); 428 r.upper = tipc_sub_read(sb, seq.upper); 429 filter = tipc_sub_read(sb, filter); 430 431 tipc_sub_get(sub); 432 list_add(&sub->service_list, &service->subscriptions); 433 434 if (filter & TIPC_SUB_NO_STATUS) 435 return; 436 437 INIT_LIST_HEAD(&publ_list); 438 service_range_foreach_match(sr, service, r.lower, r.upper) { 439 first = NULL; 440 list_for_each_entry(p, &sr->all_publ, all_publ) { 441 if (filter & TIPC_SUB_PORTS) 442 list_add_tail(&p->list, &publ_list); 443 else if (!first || publication_after(first, p)) 444 /* Pick this range's *first* publication */ 445 first = p; 446 } 447 if (first) 448 list_add_tail(&first->list, &publ_list); 449 } 450 451 /* Sort the publications before reporting */ 452 list_sort(NULL, &publ_list, tipc_publ_sort); 453 list_for_each_entry_safe(p, tmp, &publ_list, list) { 454 tipc_sub_report_overlap(sub, p->sr.lower, p->sr.upper, 455 TIPC_PUBLISHED, p->sk.ref, p->sk.node, 456 p->scope, true); 457 list_del_init(&p->list); 458 } 459 } 460 461 static struct tipc_service *tipc_service_find(struct net *net, u32 type) 462 { 463 struct name_table *nt = tipc_name_table(net); 464 struct hlist_head *service_head; 465 struct tipc_service *service; 466 467 service_head = &nt->services[hash(type)]; 468 hlist_for_each_entry_rcu(service, service_head, service_list) { 469 if (service->type == type) 470 return service; 471 } 472 return NULL; 473 }; 474 475 struct publication *tipc_nametbl_insert_publ(struct net *net, u32 type, 476 u32 lower, u32 upper, 477 u32 scope, u32 node, 478 u32 port, u32 key) 479 { 480 struct name_table *nt = tipc_name_table(net); 481 struct tipc_service *sc; 482 struct publication *p; 483 484 p = tipc_publ_create(type, lower, upper, scope, node, port, key); 485 if (!p) 486 return NULL; 487 488 if (scope > TIPC_NODE_SCOPE || lower > upper) { 489 pr_debug("Failed to bind illegal {%u,%u,%u} with scope %u\n", 490 type, lower, upper, scope); 491 return NULL; 492 } 493 sc = tipc_service_find(net, type); 494 if (!sc) 495 sc = tipc_service_create(type, &nt->services[hash(type)]); 496 if (sc && tipc_service_insert_publ(net, sc, p)) 497 return p; 498 kfree(p); 499 return NULL; 500 } 501 502 struct publication *tipc_nametbl_remove_publ(struct net *net, u32 type, 503 u32 lower, u32 upper, 504 u32 node, u32 key) 505 { 506 struct tipc_service *sc = tipc_service_find(net, type); 507 struct tipc_subscription *sub, *tmp; 508 struct service_range *sr = NULL; 509 struct publication *p = NULL; 510 bool last; 511 512 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, node, 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 p->sk.ref, node, p->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_translate - 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 exit: 554 * - if translation is deferred to another node, leave 'dnode' unchanged and 555 * return 0 556 * - if translation is attempted and succeeds, set 'dnode' to the publishing 557 * node and return the published (non-zero) port number 558 * - if translation is attempted and fails, set 'dnode' to 0 and return 0 559 * 560 * Note that for legacy users (node configured with Z.C.N address format) the 561 * 'closest-first' lookup algorithm must be maintained, i.e., if dnode is 0 562 * we must look in the local binding list first 563 */ 564 u32 tipc_nametbl_translate(struct net *net, u32 type, u32 instance, u32 *dnode) 565 { 566 struct tipc_net *tn = tipc_net(net); 567 bool legacy = tn->legacy_addr_format; 568 u32 self = tipc_own_addr(net); 569 struct service_range *sr; 570 struct tipc_service *sc; 571 struct list_head *list; 572 struct publication *p; 573 u32 port = 0; 574 u32 node = 0; 575 576 if (!tipc_in_scope(legacy, *dnode, self)) 577 return 0; 578 579 rcu_read_lock(); 580 sc = tipc_service_find(net, type); 581 if (unlikely(!sc)) 582 goto exit; 583 584 spin_lock_bh(&sc->lock); 585 service_range_foreach_match(sr, sc, instance, instance) { 586 /* Select lookup algo: local, closest-first or round-robin */ 587 if (*dnode == self) { 588 list = &sr->local_publ; 589 if (list_empty(list)) 590 continue; 591 p = list_first_entry(list, struct publication, 592 local_publ); 593 list_move_tail(&p->local_publ, &sr->local_publ); 594 } else if (legacy && !*dnode && !list_empty(&sr->local_publ)) { 595 list = &sr->local_publ; 596 p = list_first_entry(list, struct publication, 597 local_publ); 598 list_move_tail(&p->local_publ, &sr->local_publ); 599 } else { 600 list = &sr->all_publ; 601 p = list_first_entry(list, struct publication, 602 all_publ); 603 list_move_tail(&p->all_publ, &sr->all_publ); 604 } 605 port = p->sk.ref; 606 node = p->sk.node; 607 /* Todo: as for legacy, pick the first matching range only, a 608 * "true" round-robin will be performed as needed. 609 */ 610 break; 611 } 612 spin_unlock_bh(&sc->lock); 613 614 exit: 615 rcu_read_unlock(); 616 *dnode = node; 617 return port; 618 } 619 620 bool tipc_nametbl_lookup(struct net *net, u32 type, u32 instance, u32 scope, 621 struct list_head *dsts, int *dstcnt, u32 exclude, 622 bool all) 623 { 624 u32 self = tipc_own_addr(net); 625 struct service_range *sr; 626 struct tipc_service *sc; 627 struct publication *p; 628 629 *dstcnt = 0; 630 rcu_read_lock(); 631 sc = tipc_service_find(net, type); 632 if (unlikely(!sc)) 633 goto exit; 634 635 spin_lock_bh(&sc->lock); 636 637 /* Todo: a full search i.e. service_range_foreach_match() instead? */ 638 sr = service_range_match_first(sc->ranges.rb_node, instance, instance); 639 if (!sr) 640 goto no_match; 641 642 list_for_each_entry(p, &sr->all_publ, all_publ) { 643 if (p->scope != scope) 644 continue; 645 if (p->sk.ref == exclude && p->sk.node == self) 646 continue; 647 tipc_dest_push(dsts, p->sk.node, p->sk.ref); 648 (*dstcnt)++; 649 if (all) 650 continue; 651 list_move_tail(&p->all_publ, &sr->all_publ); 652 break; 653 } 654 no_match: 655 spin_unlock_bh(&sc->lock); 656 exit: 657 rcu_read_unlock(); 658 return !list_empty(dsts); 659 } 660 661 void tipc_nametbl_mc_lookup(struct net *net, u32 type, u32 lower, u32 upper, 662 u32 scope, bool exact, struct list_head *dports) 663 { 664 struct service_range *sr; 665 struct tipc_service *sc; 666 struct publication *p; 667 668 rcu_read_lock(); 669 sc = tipc_service_find(net, type); 670 if (!sc) 671 goto exit; 672 673 spin_lock_bh(&sc->lock); 674 service_range_foreach_match(sr, sc, lower, upper) { 675 list_for_each_entry(p, &sr->local_publ, local_publ) { 676 if (p->scope == scope || (!exact && p->scope < scope)) 677 tipc_dest_push(dports, 0, p->sk.ref); 678 } 679 } 680 spin_unlock_bh(&sc->lock); 681 exit: 682 rcu_read_unlock(); 683 } 684 685 /* tipc_nametbl_lookup_dst_nodes - find broadcast destination nodes 686 * - Creates list of nodes that overlap the given multicast address 687 * - Determines if any node local destinations overlap 688 */ 689 void tipc_nametbl_lookup_dst_nodes(struct net *net, u32 type, u32 lower, 690 u32 upper, struct tipc_nlist *nodes) 691 { 692 struct service_range *sr; 693 struct tipc_service *sc; 694 struct publication *p; 695 696 rcu_read_lock(); 697 sc = tipc_service_find(net, type); 698 if (!sc) 699 goto exit; 700 701 spin_lock_bh(&sc->lock); 702 service_range_foreach_match(sr, sc, lower, upper) { 703 list_for_each_entry(p, &sr->all_publ, all_publ) { 704 tipc_nlist_add(nodes, p->sk.node); 705 } 706 } 707 spin_unlock_bh(&sc->lock); 708 exit: 709 rcu_read_unlock(); 710 } 711 712 /* tipc_nametbl_build_group - build list of communication group members 713 */ 714 void tipc_nametbl_build_group(struct net *net, struct tipc_group *grp, 715 u32 type, u32 scope) 716 { 717 struct service_range *sr; 718 struct tipc_service *sc; 719 struct publication *p; 720 struct rb_node *n; 721 722 rcu_read_lock(); 723 sc = tipc_service_find(net, type); 724 if (!sc) 725 goto exit; 726 727 spin_lock_bh(&sc->lock); 728 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) { 729 sr = container_of(n, struct service_range, tree_node); 730 list_for_each_entry(p, &sr->all_publ, all_publ) { 731 if (p->scope != scope) 732 continue; 733 tipc_group_add_member(grp, p->sk.node, p->sk.ref, p->sr.lower); 734 } 735 } 736 spin_unlock_bh(&sc->lock); 737 exit: 738 rcu_read_unlock(); 739 } 740 741 /* tipc_nametbl_publish - add service binding to name table 742 */ 743 struct publication *tipc_nametbl_publish(struct net *net, struct tipc_uaddr *ua, 744 struct tipc_socket_addr *sk, u32 key) 745 { 746 struct name_table *nt = tipc_name_table(net); 747 struct tipc_net *tn = tipc_net(net); 748 struct publication *p = NULL; 749 struct sk_buff *skb = NULL; 750 u32 rc_dests; 751 752 spin_lock_bh(&tn->nametbl_lock); 753 754 if (nt->local_publ_count >= TIPC_MAX_PUBL) { 755 pr_warn("Bind failed, max limit %u reached\n", TIPC_MAX_PUBL); 756 goto exit; 757 } 758 759 p = tipc_nametbl_insert_publ(net, ua->sr.type, ua->sr.lower, 760 ua->sr.upper, ua->scope, 761 sk->node, sk->ref, key); 762 if (p) { 763 nt->local_publ_count++; 764 skb = tipc_named_publish(net, p); 765 } 766 rc_dests = nt->rc_dests; 767 exit: 768 spin_unlock_bh(&tn->nametbl_lock); 769 770 if (skb) 771 tipc_node_broadcast(net, skb, rc_dests); 772 return p; 773 774 } 775 776 /** 777 * tipc_nametbl_withdraw - withdraw a service binding 778 * @net: network namespace 779 * @type: service type 780 * @lower: service range lower bound 781 * @upper: service range upper bound 782 * @key: target publication key 783 */ 784 int tipc_nametbl_withdraw(struct net *net, u32 type, u32 lower, 785 u32 upper, u32 key) 786 { 787 struct name_table *nt = tipc_name_table(net); 788 struct tipc_net *tn = tipc_net(net); 789 u32 self = tipc_own_addr(net); 790 struct sk_buff *skb = NULL; 791 struct publication *p; 792 u32 rc_dests; 793 794 spin_lock_bh(&tn->nametbl_lock); 795 796 p = tipc_nametbl_remove_publ(net, type, lower, upper, self, key); 797 if (p) { 798 nt->local_publ_count--; 799 skb = tipc_named_withdraw(net, p); 800 list_del_init(&p->binding_sock); 801 kfree_rcu(p, rcu); 802 } else { 803 pr_err("Failed to remove local publication {%u,%u,%u}/%u\n", 804 type, lower, upper, key); 805 } 806 rc_dests = nt->rc_dests; 807 spin_unlock_bh(&tn->nametbl_lock); 808 809 if (skb) { 810 tipc_node_broadcast(net, skb, rc_dests); 811 return 1; 812 } 813 return 0; 814 } 815 816 /** 817 * tipc_nametbl_subscribe - add a subscription object to the name table 818 * @sub: subscription to add 819 */ 820 bool tipc_nametbl_subscribe(struct tipc_subscription *sub) 821 { 822 struct name_table *nt = tipc_name_table(sub->net); 823 struct tipc_net *tn = tipc_net(sub->net); 824 struct tipc_subscr *s = &sub->evt.s; 825 u32 type = tipc_sub_read(s, seq.type); 826 struct tipc_service *sc; 827 bool res = true; 828 829 spin_lock_bh(&tn->nametbl_lock); 830 sc = tipc_service_find(sub->net, type); 831 if (!sc) 832 sc = tipc_service_create(type, &nt->services[hash(type)]); 833 if (sc) { 834 spin_lock_bh(&sc->lock); 835 tipc_service_subscribe(sc, sub); 836 spin_unlock_bh(&sc->lock); 837 } else { 838 pr_warn("Failed to subscribe for {%u,%u,%u}\n", type, 839 tipc_sub_read(s, seq.lower), 840 tipc_sub_read(s, seq.upper)); 841 res = false; 842 } 843 spin_unlock_bh(&tn->nametbl_lock); 844 return res; 845 } 846 847 /** 848 * tipc_nametbl_unsubscribe - remove a subscription object from name table 849 * @sub: subscription to remove 850 */ 851 void tipc_nametbl_unsubscribe(struct tipc_subscription *sub) 852 { 853 struct tipc_net *tn = tipc_net(sub->net); 854 struct tipc_subscr *s = &sub->evt.s; 855 u32 type = tipc_sub_read(s, seq.type); 856 struct tipc_service *sc; 857 858 spin_lock_bh(&tn->nametbl_lock); 859 sc = tipc_service_find(sub->net, type); 860 if (!sc) 861 goto exit; 862 863 spin_lock_bh(&sc->lock); 864 list_del_init(&sub->service_list); 865 tipc_sub_put(sub); 866 867 /* Delete service item if no more publications and subscriptions */ 868 if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) { 869 hlist_del_init_rcu(&sc->service_list); 870 kfree_rcu(sc, rcu); 871 } 872 spin_unlock_bh(&sc->lock); 873 exit: 874 spin_unlock_bh(&tn->nametbl_lock); 875 } 876 877 int tipc_nametbl_init(struct net *net) 878 { 879 struct tipc_net *tn = tipc_net(net); 880 struct name_table *nt; 881 int i; 882 883 nt = kzalloc(sizeof(*nt), GFP_KERNEL); 884 if (!nt) 885 return -ENOMEM; 886 887 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) 888 INIT_HLIST_HEAD(&nt->services[i]); 889 890 INIT_LIST_HEAD(&nt->node_scope); 891 INIT_LIST_HEAD(&nt->cluster_scope); 892 rwlock_init(&nt->cluster_scope_lock); 893 tn->nametbl = nt; 894 spin_lock_init(&tn->nametbl_lock); 895 return 0; 896 } 897 898 /** 899 * tipc_service_delete - purge all publications for a service and delete it 900 * @net: the associated network namespace 901 * @sc: tipc_service to delete 902 */ 903 static void tipc_service_delete(struct net *net, struct tipc_service *sc) 904 { 905 struct service_range *sr, *tmpr; 906 struct publication *p, *tmp; 907 908 spin_lock_bh(&sc->lock); 909 rbtree_postorder_for_each_entry_safe(sr, tmpr, &sc->ranges, tree_node) { 910 list_for_each_entry_safe(p, tmp, &sr->all_publ, all_publ) { 911 tipc_service_remove_publ(sr, p->sk.node, p->key); 912 kfree_rcu(p, rcu); 913 } 914 rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks); 915 kfree(sr); 916 } 917 hlist_del_init_rcu(&sc->service_list); 918 spin_unlock_bh(&sc->lock); 919 kfree_rcu(sc, rcu); 920 } 921 922 void tipc_nametbl_stop(struct net *net) 923 { 924 struct name_table *nt = tipc_name_table(net); 925 struct tipc_net *tn = tipc_net(net); 926 struct hlist_head *service_head; 927 struct tipc_service *service; 928 u32 i; 929 930 /* Verify name table is empty and purge any lingering 931 * publications, then release the name table 932 */ 933 spin_lock_bh(&tn->nametbl_lock); 934 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) { 935 if (hlist_empty(&nt->services[i])) 936 continue; 937 service_head = &nt->services[i]; 938 hlist_for_each_entry_rcu(service, service_head, service_list) { 939 tipc_service_delete(net, service); 940 } 941 } 942 spin_unlock_bh(&tn->nametbl_lock); 943 944 synchronize_net(); 945 kfree(nt); 946 } 947 948 static int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg, 949 struct tipc_service *service, 950 struct service_range *sr, 951 u32 *last_key) 952 { 953 struct publication *p; 954 struct nlattr *attrs; 955 struct nlattr *b; 956 void *hdr; 957 958 if (*last_key) { 959 list_for_each_entry(p, &sr->all_publ, all_publ) 960 if (p->key == *last_key) 961 break; 962 if (p->key != *last_key) 963 return -EPIPE; 964 } else { 965 p = list_first_entry(&sr->all_publ, 966 struct publication, 967 all_publ); 968 } 969 970 list_for_each_entry_from(p, &sr->all_publ, all_publ) { 971 *last_key = p->key; 972 973 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, 974 &tipc_genl_family, NLM_F_MULTI, 975 TIPC_NL_NAME_TABLE_GET); 976 if (!hdr) 977 return -EMSGSIZE; 978 979 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE); 980 if (!attrs) 981 goto msg_full; 982 983 b = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE_PUBL); 984 if (!b) 985 goto attr_msg_full; 986 987 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, service->type)) 988 goto publ_msg_full; 989 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sr->lower)) 990 goto publ_msg_full; 991 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sr->upper)) 992 goto publ_msg_full; 993 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope)) 994 goto publ_msg_full; 995 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->sk.node)) 996 goto publ_msg_full; 997 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->sk.ref)) 998 goto publ_msg_full; 999 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key)) 1000 goto publ_msg_full; 1001 1002 nla_nest_end(msg->skb, b); 1003 nla_nest_end(msg->skb, attrs); 1004 genlmsg_end(msg->skb, hdr); 1005 } 1006 *last_key = 0; 1007 1008 return 0; 1009 1010 publ_msg_full: 1011 nla_nest_cancel(msg->skb, b); 1012 attr_msg_full: 1013 nla_nest_cancel(msg->skb, attrs); 1014 msg_full: 1015 genlmsg_cancel(msg->skb, hdr); 1016 1017 return -EMSGSIZE; 1018 } 1019 1020 static int __tipc_nl_service_range_list(struct tipc_nl_msg *msg, 1021 struct tipc_service *sc, 1022 u32 *last_lower, u32 *last_key) 1023 { 1024 struct service_range *sr; 1025 struct rb_node *n; 1026 int err; 1027 1028 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) { 1029 sr = container_of(n, struct service_range, tree_node); 1030 if (sr->lower < *last_lower) 1031 continue; 1032 err = __tipc_nl_add_nametable_publ(msg, sc, sr, last_key); 1033 if (err) { 1034 *last_lower = sr->lower; 1035 return err; 1036 } 1037 } 1038 *last_lower = 0; 1039 return 0; 1040 } 1041 1042 static int tipc_nl_service_list(struct net *net, struct tipc_nl_msg *msg, 1043 u32 *last_type, u32 *last_lower, u32 *last_key) 1044 { 1045 struct tipc_net *tn = tipc_net(net); 1046 struct tipc_service *service = NULL; 1047 struct hlist_head *head; 1048 int err; 1049 int i; 1050 1051 if (*last_type) 1052 i = hash(*last_type); 1053 else 1054 i = 0; 1055 1056 for (; i < TIPC_NAMETBL_SIZE; i++) { 1057 head = &tn->nametbl->services[i]; 1058 1059 if (*last_type || 1060 (!i && *last_key && (*last_lower == *last_key))) { 1061 service = tipc_service_find(net, *last_type); 1062 if (!service) 1063 return -EPIPE; 1064 } else { 1065 hlist_for_each_entry_rcu(service, head, service_list) 1066 break; 1067 if (!service) 1068 continue; 1069 } 1070 1071 hlist_for_each_entry_from_rcu(service, service_list) { 1072 spin_lock_bh(&service->lock); 1073 err = __tipc_nl_service_range_list(msg, service, 1074 last_lower, 1075 last_key); 1076 1077 if (err) { 1078 *last_type = service->type; 1079 spin_unlock_bh(&service->lock); 1080 return err; 1081 } 1082 spin_unlock_bh(&service->lock); 1083 } 1084 *last_type = 0; 1085 } 1086 return 0; 1087 } 1088 1089 int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb) 1090 { 1091 struct net *net = sock_net(skb->sk); 1092 u32 last_type = cb->args[0]; 1093 u32 last_lower = cb->args[1]; 1094 u32 last_key = cb->args[2]; 1095 int done = cb->args[3]; 1096 struct tipc_nl_msg msg; 1097 int err; 1098 1099 if (done) 1100 return 0; 1101 1102 msg.skb = skb; 1103 msg.portid = NETLINK_CB(cb->skb).portid; 1104 msg.seq = cb->nlh->nlmsg_seq; 1105 1106 rcu_read_lock(); 1107 err = tipc_nl_service_list(net, &msg, &last_type, 1108 &last_lower, &last_key); 1109 if (!err) { 1110 done = 1; 1111 } else if (err != -EMSGSIZE) { 1112 /* We never set seq or call nl_dump_check_consistent() this 1113 * means that setting prev_seq here will cause the consistence 1114 * check to fail in the netlink callback handler. Resulting in 1115 * the NLMSG_DONE message having the NLM_F_DUMP_INTR flag set if 1116 * we got an error. 1117 */ 1118 cb->prev_seq = 1; 1119 } 1120 rcu_read_unlock(); 1121 1122 cb->args[0] = last_type; 1123 cb->args[1] = last_lower; 1124 cb->args[2] = last_key; 1125 cb->args[3] = done; 1126 1127 return skb->len; 1128 } 1129 1130 struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port) 1131 { 1132 struct tipc_dest *dst; 1133 1134 list_for_each_entry(dst, l, list) { 1135 if (dst->node == node && dst->port == port) 1136 return dst; 1137 } 1138 return NULL; 1139 } 1140 1141 bool tipc_dest_push(struct list_head *l, u32 node, u32 port) 1142 { 1143 struct tipc_dest *dst; 1144 1145 if (tipc_dest_find(l, node, port)) 1146 return false; 1147 1148 dst = kmalloc(sizeof(*dst), GFP_ATOMIC); 1149 if (unlikely(!dst)) 1150 return false; 1151 dst->node = node; 1152 dst->port = port; 1153 list_add(&dst->list, l); 1154 return true; 1155 } 1156 1157 bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port) 1158 { 1159 struct tipc_dest *dst; 1160 1161 if (list_empty(l)) 1162 return false; 1163 dst = list_first_entry(l, typeof(*dst), list); 1164 if (port) 1165 *port = dst->port; 1166 if (node) 1167 *node = dst->node; 1168 list_del(&dst->list); 1169 kfree(dst); 1170 return true; 1171 } 1172 1173 bool tipc_dest_del(struct list_head *l, u32 node, u32 port) 1174 { 1175 struct tipc_dest *dst; 1176 1177 dst = tipc_dest_find(l, node, port); 1178 if (!dst) 1179 return false; 1180 list_del(&dst->list); 1181 kfree(dst); 1182 return true; 1183 } 1184 1185 void tipc_dest_list_purge(struct list_head *l) 1186 { 1187 struct tipc_dest *dst, *tmp; 1188 1189 list_for_each_entry_safe(dst, tmp, l, list) { 1190 list_del(&dst->list); 1191 kfree(dst); 1192 } 1193 } 1194 1195 int tipc_dest_list_len(struct list_head *l) 1196 { 1197 struct tipc_dest *dst; 1198 int i = 0; 1199 1200 list_for_each_entry(dst, l, list) { 1201 i++; 1202 } 1203 return i; 1204 } 1205