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 struct tipc_uaddr *ua) 279 { 280 struct service_range *sr; 281 282 service_range_foreach_match(sr, sc, ua->sr.lower, ua->sr.upper) { 283 /* Look for exact match */ 284 if (sr->lower == ua->sr.lower && sr->upper == ua->sr.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 struct publication *p) 293 { 294 struct rb_node **n, *parent = NULL; 295 struct service_range *sr; 296 u32 lower = p->sr.lower; 297 u32 upper = p->sr.upper; 298 299 n = &sc->ranges.rb_node; 300 while (*n) { 301 parent = *n; 302 sr = service_range_entry(parent); 303 if (lower == sr->lower && upper == sr->upper) 304 return sr; 305 if (sr->max < upper) 306 sr->max = upper; 307 if (lower <= sr->lower) 308 n = &parent->rb_left; 309 else 310 n = &parent->rb_right; 311 } 312 sr = kzalloc(sizeof(*sr), GFP_ATOMIC); 313 if (!sr) 314 return NULL; 315 sr->lower = lower; 316 sr->upper = upper; 317 sr->max = upper; 318 INIT_LIST_HEAD(&sr->local_publ); 319 INIT_LIST_HEAD(&sr->all_publ); 320 rb_link_node(&sr->tree_node, parent, n); 321 rb_insert_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks); 322 return sr; 323 } 324 325 static bool tipc_service_insert_publ(struct net *net, 326 struct tipc_service *sc, 327 struct publication *p) 328 { 329 struct tipc_subscription *sub, *tmp; 330 struct service_range *sr; 331 struct publication *_p; 332 u32 node = p->sk.node; 333 bool first = false; 334 bool res = false; 335 336 spin_lock_bh(&sc->lock); 337 sr = tipc_service_create_range(sc, p); 338 if (!sr) 339 goto exit; 340 341 first = list_empty(&sr->all_publ); 342 343 /* Return if the publication already exists */ 344 list_for_each_entry(_p, &sr->all_publ, all_publ) { 345 if (_p->key == p->key && (!_p->sk.node || _p->sk.node == node)) 346 goto exit; 347 } 348 349 if (in_own_node(net, p->sk.node)) 350 list_add(&p->local_publ, &sr->local_publ); 351 list_add(&p->all_publ, &sr->all_publ); 352 p->id = sc->publ_cnt++; 353 354 /* Any subscriptions waiting for notification? */ 355 list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) { 356 tipc_sub_report_overlap(sub, p->sr.lower, p->sr.upper, 357 TIPC_PUBLISHED, p->sk.ref, p->sk.node, 358 p->scope, first); 359 } 360 res = true; 361 exit: 362 if (!res) 363 pr_warn("Failed to bind to %u,%u,%u\n", 364 p->sr.type, p->sr.lower, p->sr.upper); 365 spin_unlock_bh(&sc->lock); 366 return res; 367 } 368 369 /** 370 * tipc_service_remove_publ - remove a publication from a service 371 * @r: service_range to remove publication from 372 * @sk: address publishing socket 373 * @key: target publication key 374 */ 375 static struct publication *tipc_service_remove_publ(struct service_range *r, 376 struct tipc_socket_addr *sk, 377 u32 key) 378 { 379 struct publication *p; 380 u32 node = sk->node; 381 382 list_for_each_entry(p, &r->all_publ, all_publ) { 383 if (p->key != key || (node && node != p->sk.node)) 384 continue; 385 list_del(&p->all_publ); 386 list_del(&p->local_publ); 387 return p; 388 } 389 return NULL; 390 } 391 392 /* 393 * Code reused: time_after32() for the same purpose 394 */ 395 #define publication_after(pa, pb) time_after32((pa)->id, (pb)->id) 396 static int tipc_publ_sort(void *priv, struct list_head *a, 397 struct list_head *b) 398 { 399 struct publication *pa, *pb; 400 401 pa = container_of(a, struct publication, list); 402 pb = container_of(b, struct publication, list); 403 return publication_after(pa, pb); 404 } 405 406 /** 407 * tipc_service_subscribe - attach a subscription, and optionally 408 * issue the prescribed number of events if there is any service 409 * range overlapping with the requested range 410 * @service: the tipc_service to attach the @sub to 411 * @sub: the subscription to attach 412 */ 413 static void tipc_service_subscribe(struct tipc_service *service, 414 struct tipc_subscription *sub) 415 { 416 struct tipc_subscr *sb = &sub->evt.s; 417 struct publication *p, *first, *tmp; 418 struct list_head publ_list; 419 struct service_range *sr; 420 struct tipc_service_range r; 421 u32 filter; 422 423 r.type = tipc_sub_read(sb, seq.type); 424 r.lower = tipc_sub_read(sb, seq.lower); 425 r.upper = tipc_sub_read(sb, seq.upper); 426 filter = tipc_sub_read(sb, filter); 427 428 tipc_sub_get(sub); 429 list_add(&sub->service_list, &service->subscriptions); 430 431 if (filter & TIPC_SUB_NO_STATUS) 432 return; 433 434 INIT_LIST_HEAD(&publ_list); 435 service_range_foreach_match(sr, service, r.lower, r.upper) { 436 first = NULL; 437 list_for_each_entry(p, &sr->all_publ, all_publ) { 438 if (filter & TIPC_SUB_PORTS) 439 list_add_tail(&p->list, &publ_list); 440 else if (!first || publication_after(first, p)) 441 /* Pick this range's *first* publication */ 442 first = p; 443 } 444 if (first) 445 list_add_tail(&first->list, &publ_list); 446 } 447 448 /* Sort the publications before reporting */ 449 list_sort(NULL, &publ_list, tipc_publ_sort); 450 list_for_each_entry_safe(p, tmp, &publ_list, list) { 451 tipc_sub_report_overlap(sub, p->sr.lower, p->sr.upper, 452 TIPC_PUBLISHED, p->sk.ref, p->sk.node, 453 p->scope, true); 454 list_del_init(&p->list); 455 } 456 } 457 458 static struct tipc_service *tipc_service_find(struct net *net, u32 type) 459 { 460 struct name_table *nt = tipc_name_table(net); 461 struct hlist_head *service_head; 462 struct tipc_service *service; 463 464 service_head = &nt->services[hash(type)]; 465 hlist_for_each_entry_rcu(service, service_head, service_list) { 466 if (service->type == type) 467 return service; 468 } 469 return NULL; 470 }; 471 472 struct publication *tipc_nametbl_insert_publ(struct net *net, 473 struct tipc_uaddr *ua, 474 struct tipc_socket_addr *sk, 475 u32 key) 476 { 477 struct name_table *nt = tipc_name_table(net); 478 struct tipc_service *sc; 479 struct publication *p; 480 u32 type = ua->sr.type; 481 482 p = tipc_publ_create(ua, sk, key); 483 if (!p) 484 return NULL; 485 486 if (ua->sr.lower > ua->sr.upper) { 487 pr_debug("Failed to bind illegal {%u,%u,%u} from node %u\n", 488 type, ua->sr.lower, ua->sr.upper, sk->node); 489 return NULL; 490 } 491 sc = tipc_service_find(net, type); 492 if (!sc) 493 sc = tipc_service_create(type, &nt->services[hash(type)]); 494 if (sc && tipc_service_insert_publ(net, sc, p)) 495 return p; 496 kfree(p); 497 return NULL; 498 } 499 500 struct publication *tipc_nametbl_remove_publ(struct net *net, 501 struct tipc_uaddr *ua, 502 struct tipc_socket_addr *sk, 503 u32 key) 504 { 505 struct tipc_subscription *sub, *tmp; 506 struct publication *p = NULL; 507 struct service_range *sr; 508 struct tipc_service *sc; 509 u32 upper = ua->sr.upper; 510 u32 lower = ua->sr.lower; 511 bool last; 512 513 sc = tipc_service_find(net, ua->sr.type); 514 if (!sc) 515 return NULL; 516 517 spin_lock_bh(&sc->lock); 518 sr = tipc_service_find_range(sc, ua); 519 if (!sr) 520 goto exit; 521 p = tipc_service_remove_publ(sr, sk, key); 522 if (!p) 523 goto exit; 524 525 /* Notify any waiting subscriptions */ 526 last = list_empty(&sr->all_publ); 527 list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) { 528 tipc_sub_report_overlap(sub, lower, upper, TIPC_WITHDRAWN, 529 sk->ref, sk->node, ua->scope, last); 530 } 531 532 /* Remove service range item if this was its last publication */ 533 if (list_empty(&sr->all_publ)) { 534 rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks); 535 kfree(sr); 536 } 537 538 /* Delete service item if this no more publications and subscriptions */ 539 if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) { 540 hlist_del_init_rcu(&sc->service_list); 541 kfree_rcu(sc, rcu); 542 } 543 exit: 544 spin_unlock_bh(&sc->lock); 545 return p; 546 } 547 548 /** 549 * tipc_nametbl_lookup_anycast - perform service instance to socket translation 550 * @net: network namespace 551 * @ua: service address to look up 552 * @sk: address to socket we want to find 553 * 554 * On entry, a non-zero 'sk->node' indicates the node where we want lookup to be 555 * performed, which may not be this one. 556 * On exit: 557 * - If lookup is deferred to another node, leave 'sk->node' unchanged and 558 * return 'true'. 559 * - If lookup is successful, set the 'sk->node' and 'sk->ref' (== portid) which 560 * represent the bound socket and return 'true'. 561 * - If lookup fails, return 'false' 562 * 563 * Note that for legacy users (node configured with Z.C.N address format) the 564 * 'closest-first' lookup algorithm must be maintained, i.e., if sk.node is 0 565 * we must look in the local binding list first 566 */ 567 bool tipc_nametbl_lookup_anycast(struct net *net, 568 struct tipc_uaddr *ua, 569 struct tipc_socket_addr *sk) 570 { 571 struct tipc_net *tn = tipc_net(net); 572 bool legacy = tn->legacy_addr_format; 573 u32 self = tipc_own_addr(net); 574 u32 inst = ua->sa.instance; 575 struct service_range *r; 576 struct tipc_service *sc; 577 struct publication *p; 578 struct list_head *l; 579 bool res = false; 580 581 if (!tipc_in_scope(legacy, sk->node, self)) 582 return true; 583 584 rcu_read_lock(); 585 sc = tipc_service_find(net, ua->sr.type); 586 if (unlikely(!sc)) 587 goto exit; 588 589 spin_lock_bh(&sc->lock); 590 service_range_foreach_match(r, sc, inst, inst) { 591 /* Select lookup algo: local, closest-first or round-robin */ 592 if (sk->node == self) { 593 l = &r->local_publ; 594 if (list_empty(l)) 595 continue; 596 p = list_first_entry(l, struct publication, local_publ); 597 list_move_tail(&p->local_publ, &r->local_publ); 598 } else if (legacy && !sk->node && !list_empty(&r->local_publ)) { 599 l = &r->local_publ; 600 p = list_first_entry(l, struct publication, local_publ); 601 list_move_tail(&p->local_publ, &r->local_publ); 602 } else { 603 l = &r->all_publ; 604 p = list_first_entry(l, struct publication, all_publ); 605 list_move_tail(&p->all_publ, &r->all_publ); 606 } 607 *sk = p->sk; 608 res = true; 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 return res; 619 } 620 621 /* tipc_nametbl_lookup_group(): lookup destinaton(s) in a communication group 622 * Returns a list of one (== group anycast) or more (== group multicast) 623 * destination socket/node pairs matching the given address. 624 * The requester may or may not want to exclude himself from the list. 625 */ 626 bool tipc_nametbl_lookup_group(struct net *net, struct tipc_uaddr *ua, 627 struct list_head *dsts, int *dstcnt, 628 u32 exclude, bool mcast) 629 { 630 u32 self = tipc_own_addr(net); 631 u32 inst = ua->sa.instance; 632 struct service_range *sr; 633 struct tipc_service *sc; 634 struct publication *p; 635 636 *dstcnt = 0; 637 rcu_read_lock(); 638 sc = tipc_service_find(net, ua->sa.type); 639 if (unlikely(!sc)) 640 goto exit; 641 642 spin_lock_bh(&sc->lock); 643 644 /* Todo: a full search i.e. service_range_foreach_match() instead? */ 645 sr = service_range_match_first(sc->ranges.rb_node, inst, inst); 646 if (!sr) 647 goto no_match; 648 649 list_for_each_entry(p, &sr->all_publ, all_publ) { 650 if (p->scope != ua->scope) 651 continue; 652 if (p->sk.ref == exclude && p->sk.node == self) 653 continue; 654 tipc_dest_push(dsts, p->sk.node, p->sk.ref); 655 (*dstcnt)++; 656 if (mcast) 657 continue; 658 list_move_tail(&p->all_publ, &sr->all_publ); 659 break; 660 } 661 no_match: 662 spin_unlock_bh(&sc->lock); 663 exit: 664 rcu_read_unlock(); 665 return !list_empty(dsts); 666 } 667 668 /* tipc_nametbl_lookup_mcast_sockets(): look up node local destinaton sockets 669 * matching the given address 670 * Used on nodes which have received a multicast/broadcast message 671 * Returns a list of local sockets 672 */ 673 void tipc_nametbl_lookup_mcast_sockets(struct net *net, struct tipc_uaddr *ua, 674 bool exact, struct list_head *dports) 675 { 676 struct service_range *sr; 677 struct tipc_service *sc; 678 struct publication *p; 679 u32 scope = ua->scope; 680 681 rcu_read_lock(); 682 sc = tipc_service_find(net, ua->sr.type); 683 if (!sc) 684 goto exit; 685 686 spin_lock_bh(&sc->lock); 687 service_range_foreach_match(sr, sc, ua->sr.lower, ua->sr.upper) { 688 list_for_each_entry(p, &sr->local_publ, local_publ) { 689 if (p->scope == scope || (!exact && p->scope < scope)) 690 tipc_dest_push(dports, 0, p->sk.ref); 691 } 692 } 693 spin_unlock_bh(&sc->lock); 694 exit: 695 rcu_read_unlock(); 696 } 697 698 /* tipc_nametbl_lookup_mcast_nodes(): look up all destination nodes matching 699 * the given address. Used in sending node. 700 * Used on nodes which are sending out a multicast/broadcast message 701 * Returns a list of nodes, including own node if applicable 702 */ 703 void tipc_nametbl_lookup_mcast_nodes(struct net *net, struct tipc_uaddr *ua, 704 struct tipc_nlist *nodes) 705 { 706 struct service_range *sr; 707 struct tipc_service *sc; 708 struct publication *p; 709 710 rcu_read_lock(); 711 sc = tipc_service_find(net, ua->sr.type); 712 if (!sc) 713 goto exit; 714 715 spin_lock_bh(&sc->lock); 716 service_range_foreach_match(sr, sc, ua->sr.lower, ua->sr.upper) { 717 list_for_each_entry(p, &sr->all_publ, all_publ) { 718 tipc_nlist_add(nodes, p->sk.node); 719 } 720 } 721 spin_unlock_bh(&sc->lock); 722 exit: 723 rcu_read_unlock(); 724 } 725 726 /* tipc_nametbl_build_group - build list of communication group members 727 */ 728 void tipc_nametbl_build_group(struct net *net, struct tipc_group *grp, 729 u32 type, u32 scope) 730 { 731 struct service_range *sr; 732 struct tipc_service *sc; 733 struct publication *p; 734 struct rb_node *n; 735 736 rcu_read_lock(); 737 sc = tipc_service_find(net, type); 738 if (!sc) 739 goto exit; 740 741 spin_lock_bh(&sc->lock); 742 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) { 743 sr = container_of(n, struct service_range, tree_node); 744 list_for_each_entry(p, &sr->all_publ, all_publ) { 745 if (p->scope != scope) 746 continue; 747 tipc_group_add_member(grp, p->sk.node, p->sk.ref, p->sr.lower); 748 } 749 } 750 spin_unlock_bh(&sc->lock); 751 exit: 752 rcu_read_unlock(); 753 } 754 755 /* tipc_nametbl_publish - add service binding to name table 756 */ 757 struct publication *tipc_nametbl_publish(struct net *net, struct tipc_uaddr *ua, 758 struct tipc_socket_addr *sk, u32 key) 759 { 760 struct name_table *nt = tipc_name_table(net); 761 struct tipc_net *tn = tipc_net(net); 762 struct publication *p = NULL; 763 struct sk_buff *skb = NULL; 764 u32 rc_dests; 765 766 spin_lock_bh(&tn->nametbl_lock); 767 768 if (nt->local_publ_count >= TIPC_MAX_PUBL) { 769 pr_warn("Bind failed, max limit %u reached\n", TIPC_MAX_PUBL); 770 goto exit; 771 } 772 773 p = tipc_nametbl_insert_publ(net, ua, sk, key); 774 if (p) { 775 nt->local_publ_count++; 776 skb = tipc_named_publish(net, p); 777 } 778 rc_dests = nt->rc_dests; 779 exit: 780 spin_unlock_bh(&tn->nametbl_lock); 781 782 if (skb) 783 tipc_node_broadcast(net, skb, rc_dests); 784 return p; 785 786 } 787 788 /** 789 * tipc_nametbl_withdraw - withdraw a service binding 790 * @net: network namespace 791 * @ua: service address/range being unbound 792 * @sk: address of the socket being unbound from 793 * @key: target publication key 794 */ 795 void tipc_nametbl_withdraw(struct net *net, struct tipc_uaddr *ua, 796 struct tipc_socket_addr *sk, u32 key) 797 { 798 struct name_table *nt = tipc_name_table(net); 799 struct tipc_net *tn = tipc_net(net); 800 struct sk_buff *skb = NULL; 801 struct publication *p; 802 u32 rc_dests; 803 804 spin_lock_bh(&tn->nametbl_lock); 805 806 p = tipc_nametbl_remove_publ(net, ua, sk, key); 807 if (p) { 808 nt->local_publ_count--; 809 skb = tipc_named_withdraw(net, p); 810 list_del_init(&p->binding_sock); 811 kfree_rcu(p, rcu); 812 } else { 813 pr_err("Failed to remove local publication {%u,%u,%u}/%u\n", 814 ua->sr.type, ua->sr.lower, ua->sr.upper, key); 815 } 816 rc_dests = nt->rc_dests; 817 spin_unlock_bh(&tn->nametbl_lock); 818 819 if (skb) 820 tipc_node_broadcast(net, skb, rc_dests); 821 } 822 823 /** 824 * tipc_nametbl_subscribe - add a subscription object to the name table 825 * @sub: subscription to add 826 */ 827 bool tipc_nametbl_subscribe(struct tipc_subscription *sub) 828 { 829 struct name_table *nt = tipc_name_table(sub->net); 830 struct tipc_net *tn = tipc_net(sub->net); 831 struct tipc_subscr *s = &sub->evt.s; 832 u32 type = tipc_sub_read(s, seq.type); 833 struct tipc_service *sc; 834 bool res = true; 835 836 spin_lock_bh(&tn->nametbl_lock); 837 sc = tipc_service_find(sub->net, type); 838 if (!sc) 839 sc = tipc_service_create(type, &nt->services[hash(type)]); 840 if (sc) { 841 spin_lock_bh(&sc->lock); 842 tipc_service_subscribe(sc, sub); 843 spin_unlock_bh(&sc->lock); 844 } else { 845 pr_warn("Failed to subscribe for {%u,%u,%u}\n", type, 846 tipc_sub_read(s, seq.lower), 847 tipc_sub_read(s, seq.upper)); 848 res = false; 849 } 850 spin_unlock_bh(&tn->nametbl_lock); 851 return res; 852 } 853 854 /** 855 * tipc_nametbl_unsubscribe - remove a subscription object from name table 856 * @sub: subscription to remove 857 */ 858 void tipc_nametbl_unsubscribe(struct tipc_subscription *sub) 859 { 860 struct tipc_net *tn = tipc_net(sub->net); 861 struct tipc_subscr *s = &sub->evt.s; 862 u32 type = tipc_sub_read(s, seq.type); 863 struct tipc_service *sc; 864 865 spin_lock_bh(&tn->nametbl_lock); 866 sc = tipc_service_find(sub->net, type); 867 if (!sc) 868 goto exit; 869 870 spin_lock_bh(&sc->lock); 871 list_del_init(&sub->service_list); 872 tipc_sub_put(sub); 873 874 /* Delete service item if no more publications and subscriptions */ 875 if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) { 876 hlist_del_init_rcu(&sc->service_list); 877 kfree_rcu(sc, rcu); 878 } 879 spin_unlock_bh(&sc->lock); 880 exit: 881 spin_unlock_bh(&tn->nametbl_lock); 882 } 883 884 int tipc_nametbl_init(struct net *net) 885 { 886 struct tipc_net *tn = tipc_net(net); 887 struct name_table *nt; 888 int i; 889 890 nt = kzalloc(sizeof(*nt), GFP_KERNEL); 891 if (!nt) 892 return -ENOMEM; 893 894 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) 895 INIT_HLIST_HEAD(&nt->services[i]); 896 897 INIT_LIST_HEAD(&nt->node_scope); 898 INIT_LIST_HEAD(&nt->cluster_scope); 899 rwlock_init(&nt->cluster_scope_lock); 900 tn->nametbl = nt; 901 spin_lock_init(&tn->nametbl_lock); 902 return 0; 903 } 904 905 /** 906 * tipc_service_delete - purge all publications for a service and delete it 907 * @net: the associated network namespace 908 * @sc: tipc_service to delete 909 */ 910 static void tipc_service_delete(struct net *net, struct tipc_service *sc) 911 { 912 struct service_range *sr, *tmpr; 913 struct publication *p, *tmp; 914 915 spin_lock_bh(&sc->lock); 916 rbtree_postorder_for_each_entry_safe(sr, tmpr, &sc->ranges, tree_node) { 917 list_for_each_entry_safe(p, tmp, &sr->all_publ, all_publ) { 918 tipc_service_remove_publ(sr, &p->sk, p->key); 919 kfree_rcu(p, rcu); 920 } 921 rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks); 922 kfree(sr); 923 } 924 hlist_del_init_rcu(&sc->service_list); 925 spin_unlock_bh(&sc->lock); 926 kfree_rcu(sc, rcu); 927 } 928 929 void tipc_nametbl_stop(struct net *net) 930 { 931 struct name_table *nt = tipc_name_table(net); 932 struct tipc_net *tn = tipc_net(net); 933 struct hlist_head *service_head; 934 struct tipc_service *service; 935 u32 i; 936 937 /* Verify name table is empty and purge any lingering 938 * publications, then release the name table 939 */ 940 spin_lock_bh(&tn->nametbl_lock); 941 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) { 942 if (hlist_empty(&nt->services[i])) 943 continue; 944 service_head = &nt->services[i]; 945 hlist_for_each_entry_rcu(service, service_head, service_list) { 946 tipc_service_delete(net, service); 947 } 948 } 949 spin_unlock_bh(&tn->nametbl_lock); 950 951 synchronize_net(); 952 kfree(nt); 953 } 954 955 static int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg, 956 struct tipc_service *service, 957 struct service_range *sr, 958 u32 *last_key) 959 { 960 struct publication *p; 961 struct nlattr *attrs; 962 struct nlattr *b; 963 void *hdr; 964 965 if (*last_key) { 966 list_for_each_entry(p, &sr->all_publ, all_publ) 967 if (p->key == *last_key) 968 break; 969 if (p->key != *last_key) 970 return -EPIPE; 971 } else { 972 p = list_first_entry(&sr->all_publ, 973 struct publication, 974 all_publ); 975 } 976 977 list_for_each_entry_from(p, &sr->all_publ, all_publ) { 978 *last_key = p->key; 979 980 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, 981 &tipc_genl_family, NLM_F_MULTI, 982 TIPC_NL_NAME_TABLE_GET); 983 if (!hdr) 984 return -EMSGSIZE; 985 986 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE); 987 if (!attrs) 988 goto msg_full; 989 990 b = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE_PUBL); 991 if (!b) 992 goto attr_msg_full; 993 994 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, service->type)) 995 goto publ_msg_full; 996 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sr->lower)) 997 goto publ_msg_full; 998 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sr->upper)) 999 goto publ_msg_full; 1000 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope)) 1001 goto publ_msg_full; 1002 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->sk.node)) 1003 goto publ_msg_full; 1004 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->sk.ref)) 1005 goto publ_msg_full; 1006 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key)) 1007 goto publ_msg_full; 1008 1009 nla_nest_end(msg->skb, b); 1010 nla_nest_end(msg->skb, attrs); 1011 genlmsg_end(msg->skb, hdr); 1012 } 1013 *last_key = 0; 1014 1015 return 0; 1016 1017 publ_msg_full: 1018 nla_nest_cancel(msg->skb, b); 1019 attr_msg_full: 1020 nla_nest_cancel(msg->skb, attrs); 1021 msg_full: 1022 genlmsg_cancel(msg->skb, hdr); 1023 1024 return -EMSGSIZE; 1025 } 1026 1027 static int __tipc_nl_service_range_list(struct tipc_nl_msg *msg, 1028 struct tipc_service *sc, 1029 u32 *last_lower, u32 *last_key) 1030 { 1031 struct service_range *sr; 1032 struct rb_node *n; 1033 int err; 1034 1035 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) { 1036 sr = container_of(n, struct service_range, tree_node); 1037 if (sr->lower < *last_lower) 1038 continue; 1039 err = __tipc_nl_add_nametable_publ(msg, sc, sr, last_key); 1040 if (err) { 1041 *last_lower = sr->lower; 1042 return err; 1043 } 1044 } 1045 *last_lower = 0; 1046 return 0; 1047 } 1048 1049 static int tipc_nl_service_list(struct net *net, struct tipc_nl_msg *msg, 1050 u32 *last_type, u32 *last_lower, u32 *last_key) 1051 { 1052 struct tipc_net *tn = tipc_net(net); 1053 struct tipc_service *service = NULL; 1054 struct hlist_head *head; 1055 int err; 1056 int i; 1057 1058 if (*last_type) 1059 i = hash(*last_type); 1060 else 1061 i = 0; 1062 1063 for (; i < TIPC_NAMETBL_SIZE; i++) { 1064 head = &tn->nametbl->services[i]; 1065 1066 if (*last_type || 1067 (!i && *last_key && (*last_lower == *last_key))) { 1068 service = tipc_service_find(net, *last_type); 1069 if (!service) 1070 return -EPIPE; 1071 } else { 1072 hlist_for_each_entry_rcu(service, head, service_list) 1073 break; 1074 if (!service) 1075 continue; 1076 } 1077 1078 hlist_for_each_entry_from_rcu(service, service_list) { 1079 spin_lock_bh(&service->lock); 1080 err = __tipc_nl_service_range_list(msg, service, 1081 last_lower, 1082 last_key); 1083 1084 if (err) { 1085 *last_type = service->type; 1086 spin_unlock_bh(&service->lock); 1087 return err; 1088 } 1089 spin_unlock_bh(&service->lock); 1090 } 1091 *last_type = 0; 1092 } 1093 return 0; 1094 } 1095 1096 int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb) 1097 { 1098 struct net *net = sock_net(skb->sk); 1099 u32 last_type = cb->args[0]; 1100 u32 last_lower = cb->args[1]; 1101 u32 last_key = cb->args[2]; 1102 int done = cb->args[3]; 1103 struct tipc_nl_msg msg; 1104 int err; 1105 1106 if (done) 1107 return 0; 1108 1109 msg.skb = skb; 1110 msg.portid = NETLINK_CB(cb->skb).portid; 1111 msg.seq = cb->nlh->nlmsg_seq; 1112 1113 rcu_read_lock(); 1114 err = tipc_nl_service_list(net, &msg, &last_type, 1115 &last_lower, &last_key); 1116 if (!err) { 1117 done = 1; 1118 } else if (err != -EMSGSIZE) { 1119 /* We never set seq or call nl_dump_check_consistent() this 1120 * means that setting prev_seq here will cause the consistence 1121 * check to fail in the netlink callback handler. Resulting in 1122 * the NLMSG_DONE message having the NLM_F_DUMP_INTR flag set if 1123 * we got an error. 1124 */ 1125 cb->prev_seq = 1; 1126 } 1127 rcu_read_unlock(); 1128 1129 cb->args[0] = last_type; 1130 cb->args[1] = last_lower; 1131 cb->args[2] = last_key; 1132 cb->args[3] = done; 1133 1134 return skb->len; 1135 } 1136 1137 struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port) 1138 { 1139 struct tipc_dest *dst; 1140 1141 list_for_each_entry(dst, l, list) { 1142 if (dst->node == node && dst->port == port) 1143 return dst; 1144 } 1145 return NULL; 1146 } 1147 1148 bool tipc_dest_push(struct list_head *l, u32 node, u32 port) 1149 { 1150 struct tipc_dest *dst; 1151 1152 if (tipc_dest_find(l, node, port)) 1153 return false; 1154 1155 dst = kmalloc(sizeof(*dst), GFP_ATOMIC); 1156 if (unlikely(!dst)) 1157 return false; 1158 dst->node = node; 1159 dst->port = port; 1160 list_add(&dst->list, l); 1161 return true; 1162 } 1163 1164 bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port) 1165 { 1166 struct tipc_dest *dst; 1167 1168 if (list_empty(l)) 1169 return false; 1170 dst = list_first_entry(l, typeof(*dst), list); 1171 if (port) 1172 *port = dst->port; 1173 if (node) 1174 *node = dst->node; 1175 list_del(&dst->list); 1176 kfree(dst); 1177 return true; 1178 } 1179 1180 bool tipc_dest_del(struct list_head *l, u32 node, u32 port) 1181 { 1182 struct tipc_dest *dst; 1183 1184 dst = tipc_dest_find(l, node, port); 1185 if (!dst) 1186 return false; 1187 list_del(&dst->list); 1188 kfree(dst); 1189 return true; 1190 } 1191 1192 void tipc_dest_list_purge(struct list_head *l) 1193 { 1194 struct tipc_dest *dst, *tmp; 1195 1196 list_for_each_entry_safe(dst, tmp, l, list) { 1197 list_del(&dst->list); 1198 kfree(dst); 1199 } 1200 } 1201 1202 int tipc_dest_list_len(struct list_head *l) 1203 { 1204 struct tipc_dest *dst; 1205 int i = 0; 1206 1207 list_for_each_entry(dst, l, list) { 1208 i++; 1209 } 1210 return i; 1211 } 1212