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_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, sk, key); 760 if (p) { 761 nt->local_publ_count++; 762 skb = tipc_named_publish(net, p); 763 } 764 rc_dests = nt->rc_dests; 765 exit: 766 spin_unlock_bh(&tn->nametbl_lock); 767 768 if (skb) 769 tipc_node_broadcast(net, skb, rc_dests); 770 return p; 771 772 } 773 774 /** 775 * tipc_nametbl_withdraw - withdraw a service binding 776 * @net: network namespace 777 * @ua: service address/range being unbound 778 * @sk: address of the socket being unbound from 779 * @key: target publication key 780 */ 781 void tipc_nametbl_withdraw(struct net *net, struct tipc_uaddr *ua, 782 struct tipc_socket_addr *sk, u32 key) 783 { 784 struct name_table *nt = tipc_name_table(net); 785 struct tipc_net *tn = tipc_net(net); 786 struct sk_buff *skb = NULL; 787 struct publication *p; 788 u32 rc_dests; 789 790 spin_lock_bh(&tn->nametbl_lock); 791 792 p = tipc_nametbl_remove_publ(net, ua, sk, key); 793 if (p) { 794 nt->local_publ_count--; 795 skb = tipc_named_withdraw(net, p); 796 list_del_init(&p->binding_sock); 797 kfree_rcu(p, rcu); 798 } else { 799 pr_err("Failed to remove local publication {%u,%u,%u}/%u\n", 800 ua->sr.type, ua->sr.lower, ua->sr.upper, key); 801 } 802 rc_dests = nt->rc_dests; 803 spin_unlock_bh(&tn->nametbl_lock); 804 805 if (skb) 806 tipc_node_broadcast(net, skb, rc_dests); 807 } 808 809 /** 810 * tipc_nametbl_subscribe - add a subscription object to the name table 811 * @sub: subscription to add 812 */ 813 bool tipc_nametbl_subscribe(struct tipc_subscription *sub) 814 { 815 struct name_table *nt = tipc_name_table(sub->net); 816 struct tipc_net *tn = tipc_net(sub->net); 817 struct tipc_subscr *s = &sub->evt.s; 818 u32 type = tipc_sub_read(s, seq.type); 819 struct tipc_service *sc; 820 bool res = true; 821 822 spin_lock_bh(&tn->nametbl_lock); 823 sc = tipc_service_find(sub->net, type); 824 if (!sc) 825 sc = tipc_service_create(type, &nt->services[hash(type)]); 826 if (sc) { 827 spin_lock_bh(&sc->lock); 828 tipc_service_subscribe(sc, sub); 829 spin_unlock_bh(&sc->lock); 830 } else { 831 pr_warn("Failed to subscribe for {%u,%u,%u}\n", type, 832 tipc_sub_read(s, seq.lower), 833 tipc_sub_read(s, seq.upper)); 834 res = false; 835 } 836 spin_unlock_bh(&tn->nametbl_lock); 837 return res; 838 } 839 840 /** 841 * tipc_nametbl_unsubscribe - remove a subscription object from name table 842 * @sub: subscription to remove 843 */ 844 void tipc_nametbl_unsubscribe(struct tipc_subscription *sub) 845 { 846 struct tipc_net *tn = tipc_net(sub->net); 847 struct tipc_subscr *s = &sub->evt.s; 848 u32 type = tipc_sub_read(s, seq.type); 849 struct tipc_service *sc; 850 851 spin_lock_bh(&tn->nametbl_lock); 852 sc = tipc_service_find(sub->net, type); 853 if (!sc) 854 goto exit; 855 856 spin_lock_bh(&sc->lock); 857 list_del_init(&sub->service_list); 858 tipc_sub_put(sub); 859 860 /* Delete service item if no more publications and subscriptions */ 861 if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) { 862 hlist_del_init_rcu(&sc->service_list); 863 kfree_rcu(sc, rcu); 864 } 865 spin_unlock_bh(&sc->lock); 866 exit: 867 spin_unlock_bh(&tn->nametbl_lock); 868 } 869 870 int tipc_nametbl_init(struct net *net) 871 { 872 struct tipc_net *tn = tipc_net(net); 873 struct name_table *nt; 874 int i; 875 876 nt = kzalloc(sizeof(*nt), GFP_KERNEL); 877 if (!nt) 878 return -ENOMEM; 879 880 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) 881 INIT_HLIST_HEAD(&nt->services[i]); 882 883 INIT_LIST_HEAD(&nt->node_scope); 884 INIT_LIST_HEAD(&nt->cluster_scope); 885 rwlock_init(&nt->cluster_scope_lock); 886 tn->nametbl = nt; 887 spin_lock_init(&tn->nametbl_lock); 888 return 0; 889 } 890 891 /** 892 * tipc_service_delete - purge all publications for a service and delete it 893 * @net: the associated network namespace 894 * @sc: tipc_service to delete 895 */ 896 static void tipc_service_delete(struct net *net, struct tipc_service *sc) 897 { 898 struct service_range *sr, *tmpr; 899 struct publication *p, *tmp; 900 901 spin_lock_bh(&sc->lock); 902 rbtree_postorder_for_each_entry_safe(sr, tmpr, &sc->ranges, tree_node) { 903 list_for_each_entry_safe(p, tmp, &sr->all_publ, all_publ) { 904 tipc_service_remove_publ(sr, &p->sk, p->key); 905 kfree_rcu(p, rcu); 906 } 907 rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks); 908 kfree(sr); 909 } 910 hlist_del_init_rcu(&sc->service_list); 911 spin_unlock_bh(&sc->lock); 912 kfree_rcu(sc, rcu); 913 } 914 915 void tipc_nametbl_stop(struct net *net) 916 { 917 struct name_table *nt = tipc_name_table(net); 918 struct tipc_net *tn = tipc_net(net); 919 struct hlist_head *service_head; 920 struct tipc_service *service; 921 u32 i; 922 923 /* Verify name table is empty and purge any lingering 924 * publications, then release the name table 925 */ 926 spin_lock_bh(&tn->nametbl_lock); 927 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) { 928 if (hlist_empty(&nt->services[i])) 929 continue; 930 service_head = &nt->services[i]; 931 hlist_for_each_entry_rcu(service, service_head, service_list) { 932 tipc_service_delete(net, service); 933 } 934 } 935 spin_unlock_bh(&tn->nametbl_lock); 936 937 synchronize_net(); 938 kfree(nt); 939 } 940 941 static int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg, 942 struct tipc_service *service, 943 struct service_range *sr, 944 u32 *last_key) 945 { 946 struct publication *p; 947 struct nlattr *attrs; 948 struct nlattr *b; 949 void *hdr; 950 951 if (*last_key) { 952 list_for_each_entry(p, &sr->all_publ, all_publ) 953 if (p->key == *last_key) 954 break; 955 if (p->key != *last_key) 956 return -EPIPE; 957 } else { 958 p = list_first_entry(&sr->all_publ, 959 struct publication, 960 all_publ); 961 } 962 963 list_for_each_entry_from(p, &sr->all_publ, all_publ) { 964 *last_key = p->key; 965 966 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, 967 &tipc_genl_family, NLM_F_MULTI, 968 TIPC_NL_NAME_TABLE_GET); 969 if (!hdr) 970 return -EMSGSIZE; 971 972 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE); 973 if (!attrs) 974 goto msg_full; 975 976 b = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE_PUBL); 977 if (!b) 978 goto attr_msg_full; 979 980 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, service->type)) 981 goto publ_msg_full; 982 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sr->lower)) 983 goto publ_msg_full; 984 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sr->upper)) 985 goto publ_msg_full; 986 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope)) 987 goto publ_msg_full; 988 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->sk.node)) 989 goto publ_msg_full; 990 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->sk.ref)) 991 goto publ_msg_full; 992 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key)) 993 goto publ_msg_full; 994 995 nla_nest_end(msg->skb, b); 996 nla_nest_end(msg->skb, attrs); 997 genlmsg_end(msg->skb, hdr); 998 } 999 *last_key = 0; 1000 1001 return 0; 1002 1003 publ_msg_full: 1004 nla_nest_cancel(msg->skb, b); 1005 attr_msg_full: 1006 nla_nest_cancel(msg->skb, attrs); 1007 msg_full: 1008 genlmsg_cancel(msg->skb, hdr); 1009 1010 return -EMSGSIZE; 1011 } 1012 1013 static int __tipc_nl_service_range_list(struct tipc_nl_msg *msg, 1014 struct tipc_service *sc, 1015 u32 *last_lower, u32 *last_key) 1016 { 1017 struct service_range *sr; 1018 struct rb_node *n; 1019 int err; 1020 1021 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) { 1022 sr = container_of(n, struct service_range, tree_node); 1023 if (sr->lower < *last_lower) 1024 continue; 1025 err = __tipc_nl_add_nametable_publ(msg, sc, sr, last_key); 1026 if (err) { 1027 *last_lower = sr->lower; 1028 return err; 1029 } 1030 } 1031 *last_lower = 0; 1032 return 0; 1033 } 1034 1035 static int tipc_nl_service_list(struct net *net, struct tipc_nl_msg *msg, 1036 u32 *last_type, u32 *last_lower, u32 *last_key) 1037 { 1038 struct tipc_net *tn = tipc_net(net); 1039 struct tipc_service *service = NULL; 1040 struct hlist_head *head; 1041 int err; 1042 int i; 1043 1044 if (*last_type) 1045 i = hash(*last_type); 1046 else 1047 i = 0; 1048 1049 for (; i < TIPC_NAMETBL_SIZE; i++) { 1050 head = &tn->nametbl->services[i]; 1051 1052 if (*last_type || 1053 (!i && *last_key && (*last_lower == *last_key))) { 1054 service = tipc_service_find(net, *last_type); 1055 if (!service) 1056 return -EPIPE; 1057 } else { 1058 hlist_for_each_entry_rcu(service, head, service_list) 1059 break; 1060 if (!service) 1061 continue; 1062 } 1063 1064 hlist_for_each_entry_from_rcu(service, service_list) { 1065 spin_lock_bh(&service->lock); 1066 err = __tipc_nl_service_range_list(msg, service, 1067 last_lower, 1068 last_key); 1069 1070 if (err) { 1071 *last_type = service->type; 1072 spin_unlock_bh(&service->lock); 1073 return err; 1074 } 1075 spin_unlock_bh(&service->lock); 1076 } 1077 *last_type = 0; 1078 } 1079 return 0; 1080 } 1081 1082 int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb) 1083 { 1084 struct net *net = sock_net(skb->sk); 1085 u32 last_type = cb->args[0]; 1086 u32 last_lower = cb->args[1]; 1087 u32 last_key = cb->args[2]; 1088 int done = cb->args[3]; 1089 struct tipc_nl_msg msg; 1090 int err; 1091 1092 if (done) 1093 return 0; 1094 1095 msg.skb = skb; 1096 msg.portid = NETLINK_CB(cb->skb).portid; 1097 msg.seq = cb->nlh->nlmsg_seq; 1098 1099 rcu_read_lock(); 1100 err = tipc_nl_service_list(net, &msg, &last_type, 1101 &last_lower, &last_key); 1102 if (!err) { 1103 done = 1; 1104 } else if (err != -EMSGSIZE) { 1105 /* We never set seq or call nl_dump_check_consistent() this 1106 * means that setting prev_seq here will cause the consistence 1107 * check to fail in the netlink callback handler. Resulting in 1108 * the NLMSG_DONE message having the NLM_F_DUMP_INTR flag set if 1109 * we got an error. 1110 */ 1111 cb->prev_seq = 1; 1112 } 1113 rcu_read_unlock(); 1114 1115 cb->args[0] = last_type; 1116 cb->args[1] = last_lower; 1117 cb->args[2] = last_key; 1118 cb->args[3] = done; 1119 1120 return skb->len; 1121 } 1122 1123 struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port) 1124 { 1125 struct tipc_dest *dst; 1126 1127 list_for_each_entry(dst, l, list) { 1128 if (dst->node == node && dst->port == port) 1129 return dst; 1130 } 1131 return NULL; 1132 } 1133 1134 bool tipc_dest_push(struct list_head *l, u32 node, u32 port) 1135 { 1136 struct tipc_dest *dst; 1137 1138 if (tipc_dest_find(l, node, port)) 1139 return false; 1140 1141 dst = kmalloc(sizeof(*dst), GFP_ATOMIC); 1142 if (unlikely(!dst)) 1143 return false; 1144 dst->node = node; 1145 dst->port = port; 1146 list_add(&dst->list, l); 1147 return true; 1148 } 1149 1150 bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port) 1151 { 1152 struct tipc_dest *dst; 1153 1154 if (list_empty(l)) 1155 return false; 1156 dst = list_first_entry(l, typeof(*dst), list); 1157 if (port) 1158 *port = dst->port; 1159 if (node) 1160 *node = dst->node; 1161 list_del(&dst->list); 1162 kfree(dst); 1163 return true; 1164 } 1165 1166 bool tipc_dest_del(struct list_head *l, u32 node, u32 port) 1167 { 1168 struct tipc_dest *dst; 1169 1170 dst = tipc_dest_find(l, node, port); 1171 if (!dst) 1172 return false; 1173 list_del(&dst->list); 1174 kfree(dst); 1175 return true; 1176 } 1177 1178 void tipc_dest_list_purge(struct list_head *l) 1179 { 1180 struct tipc_dest *dst, *tmp; 1181 1182 list_for_each_entry_safe(dst, tmp, l, list) { 1183 list_del(&dst->list); 1184 kfree(dst); 1185 } 1186 } 1187 1188 int tipc_dest_list_len(struct list_head *l) 1189 { 1190 struct tipc_dest *dst; 1191 int i = 0; 1192 1193 list_for_each_entry(dst, l, list) { 1194 i++; 1195 } 1196 return i; 1197 } 1198