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1/*
2 * net/tipc/name_table.c: TIPC name table code
3 *
4 * Copyright (c) 2000-2006, 2014-2018, Ericsson AB
5 * Copyright (c) 2004-2008, 2010-2014, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include <net/sock.h>
38#include <linux/list_sort.h>
39#include <linux/rbtree_augmented.h>
40#include "core.h"
41#include "netlink.h"
42#include "name_table.h"
43#include "name_distr.h"
44#include "subscr.h"
45#include "bcast.h"
46#include "addr.h"
47#include "node.h"
48#include "group.h"
49
50/**
51 * struct service_range - container for all bindings of a service range
52 * @lower: service range lower bound
53 * @upper: service range upper bound
54 * @tree_node: member of service range RB tree
55 * @max: largest 'upper' in this node subtree
56 * @local_publ: list of identical publications made from this node
57 * Used by closest_first lookup and multicast lookup algorithm
58 * @all_publ: all publications identical to this one, whatever node and scope
59 * Used by round-robin lookup algorithm
60 */
61struct service_range {
62 u32 lower;
63 u32 upper;
64 struct rb_node tree_node;
65 u32 max;
66 struct list_head local_publ;
67 struct list_head all_publ;
68};
69
70/**
71 * struct tipc_service - container for all published instances of a service type
72 * @type: 32 bit 'type' value for service
73 * @publ_cnt: increasing counter for publications in this service
74 * @ranges: rb tree containing all service ranges for this service
75 * @service_list: links to adjacent name ranges in hash chain
76 * @subscriptions: list of subscriptions for this service type
77 * @lock: spinlock controlling access to pertaining service ranges/publications
78 * @rcu: RCU callback head used for deferred freeing
79 */
80struct tipc_service {
81 u32 type;
82 u32 publ_cnt;
83 struct rb_root ranges;
84 struct hlist_node service_list;
85 struct list_head subscriptions;
86 spinlock_t lock; /* Covers service range list */
87 struct rcu_head rcu;
88};
89
90#define service_range_upper(sr) ((sr)->upper)
91RB_DECLARE_CALLBACKS_MAX(static, sr_callbacks,
92 struct service_range, tree_node, u32, max,
93 service_range_upper)
94
95#define service_range_entry(rbtree_node) \
96 (container_of(rbtree_node, struct service_range, tree_node))
97
98#define service_range_overlap(sr, start, end) \
99 ((sr)->lower <= (end) && (sr)->upper >= (start))
100
101/**
102 * service_range_foreach_match - iterate over tipc service rbtree for each
103 * range match
104 * @sr: the service range pointer as a loop cursor
105 * @sc: the pointer to tipc service which holds the service range rbtree
106 * @start, end: the range (end >= start) for matching
107 */
108#define service_range_foreach_match(sr, sc, start, end) \
109 for (sr = service_range_match_first((sc)->ranges.rb_node, \
110 start, \
111 end); \
112 sr; \
113 sr = service_range_match_next(&(sr)->tree_node, \
114 start, \
115 end))
116
117/**
118 * service_range_match_first - find first service range matching a range
119 * @n: the root node of service range rbtree for searching
120 * @start, end: the range (end >= start) for matching
121 *
122 * Return: the leftmost service range node in the rbtree that overlaps the
123 * specific range if any. Otherwise, returns NULL.
124 */
125static struct service_range *service_range_match_first(struct rb_node *n,
126 u32 start, u32 end)
127{
128 struct service_range *sr;
129 struct rb_node *l, *r;
130
131 /* Non overlaps in tree at all? */
132 if (!n || service_range_entry(n)->max < start)
133 return NULL;
134
135 while (n) {
136 l = n->rb_left;
137 if (l && service_range_entry(l)->max >= start) {
138 /* A leftmost overlap range node must be one in the left
139 * subtree. If not, it has lower > end, then nodes on
140 * the right side cannot satisfy the condition either.
141 */
142 n = l;
143 continue;
144 }
145
146 /* No one in the left subtree can match, return if this node is
147 * an overlap i.e. leftmost.
148 */
149 sr = service_range_entry(n);
150 if (service_range_overlap(sr, start, end))
151 return sr;
152
153 /* Ok, try to lookup on the right side */
154 r = n->rb_right;
155 if (sr->lower <= end &&
156 r && service_range_entry(r)->max >= start) {
157 n = r;
158 continue;
159 }
160 break;
161 }
162
163 return NULL;
164}
165
166/**
167 * service_range_match_next - find next service range matching a range
168 * @n: a node in service range rbtree from which the searching starts
169 * @start, end: the range (end >= start) for matching
170 *
171 * Return: the next service range node to the given node in the rbtree that
172 * overlaps the specific range if any. Otherwise, returns NULL.
173 */
174static struct service_range *service_range_match_next(struct rb_node *n,
175 u32 start, u32 end)
176{
177 struct service_range *sr;
178 struct rb_node *p, *r;
179
180 while (n) {
181 r = n->rb_right;
182 if (r && service_range_entry(r)->max >= start)
183 /* A next overlap range node must be one in the right
184 * subtree. If not, it has lower > end, then any next
185 * successor (- an ancestor) of this node cannot
186 * satisfy the condition either.
187 */
188 return service_range_match_first(r, start, end);
189
190 /* No one in the right subtree can match, go up to find an
191 * ancestor of this node which is parent of a left-hand child.
192 */
193 while ((p = rb_parent(n)) && n == p->rb_right)
194 n = p;
195 if (!p)
196 break;
197
198 /* Return if this ancestor is an overlap */
199 sr = service_range_entry(p);
200 if (service_range_overlap(sr, start, end))
201 return sr;
202
203 /* Ok, try to lookup more from this ancestor */
204 if (sr->lower <= end) {
205 n = p;
206 continue;
207 }
208 break;
209 }
210
211 return NULL;
212}
213
214static int hash(int x)
215{
216 return x & (TIPC_NAMETBL_SIZE - 1);
217}
218
219/**
220 * tipc_publ_create - create a publication structure
221 */
222static struct publication *tipc_publ_create(u32 type, u32 lower, u32 upper,
223 u32 scope, u32 node, u32 port,
224 u32 key)
225{
226 struct publication *publ = kzalloc(sizeof(*publ), GFP_ATOMIC);
227
228 if (!publ)
229 return NULL;
230
231 publ->type = type;
232 publ->lower = lower;
233 publ->upper = upper;
234 publ->scope = scope;
235 publ->node = node;
236 publ->port = port;
237 publ->key = key;
238 INIT_LIST_HEAD(&publ->binding_sock);
239 INIT_LIST_HEAD(&publ->binding_node);
240 INIT_LIST_HEAD(&publ->local_publ);
241 INIT_LIST_HEAD(&publ->all_publ);
242 INIT_LIST_HEAD(&publ->list);
243 return publ;
244}
245
246/**
247 * tipc_service_create - create a service structure for the specified 'type'
248 *
249 * Allocates a single range structure and sets it to all 0's.
250 */
251static struct tipc_service *tipc_service_create(u32 type, struct hlist_head *hd)
252{
253 struct tipc_service *service = kzalloc(sizeof(*service), GFP_ATOMIC);
254
255 if (!service) {
256 pr_warn("Service creation failed, no memory\n");
257 return NULL;
258 }
259
260 spin_lock_init(&service->lock);
261 service->type = type;
262 service->ranges = RB_ROOT;
263 INIT_HLIST_NODE(&service->service_list);
264 INIT_LIST_HEAD(&service->subscriptions);
265 hlist_add_head_rcu(&service->service_list, hd);
266 return service;
267}
268
269/* tipc_service_find_range - find service range matching publication parameters
270 */
271static struct service_range *tipc_service_find_range(struct tipc_service *sc,
272 u32 lower, u32 upper)
273{
274 struct service_range *sr;
275
276 service_range_foreach_match(sr, sc, lower, upper) {
277 /* Look for exact match */
278 if (sr->lower == lower && sr->upper == upper)
279 return sr;
280 }
281
282 return NULL;
283}
284
285static struct service_range *tipc_service_create_range(struct tipc_service *sc,
286 u32 lower, u32 upper)
287{
288 struct rb_node **n, *parent = NULL;
289 struct service_range *sr;
290
291 n = &sc->ranges.rb_node;
292 while (*n) {
293 parent = *n;
294 sr = service_range_entry(parent);
295 if (lower == sr->lower && upper == sr->upper)
296 return sr;
297 if (sr->max < upper)
298 sr->max = upper;
299 if (lower <= sr->lower)
300 n = &parent->rb_left;
301 else
302 n = &parent->rb_right;
303 }
304 sr = kzalloc(sizeof(*sr), GFP_ATOMIC);
305 if (!sr)
306 return NULL;
307 sr->lower = lower;
308 sr->upper = upper;
309 sr->max = upper;
310 INIT_LIST_HEAD(&sr->local_publ);
311 INIT_LIST_HEAD(&sr->all_publ);
312 rb_link_node(&sr->tree_node, parent, n);
313 rb_insert_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks);
314 return sr;
315}
316
317static struct publication *tipc_service_insert_publ(struct net *net,
318 struct tipc_service *sc,
319 u32 type, u32 lower,
320 u32 upper, u32 scope,
321 u32 node, u32 port,
322 u32 key)
323{
324 struct tipc_subscription *sub, *tmp;
325 struct service_range *sr;
326 struct publication *p;
327 bool first = false;
328
329 sr = tipc_service_create_range(sc, lower, upper);
330 if (!sr)
331 goto err;
332
333 first = list_empty(&sr->all_publ);
334
335 /* Return if the publication already exists */
336 list_for_each_entry(p, &sr->all_publ, all_publ) {
337 if (p->key == key && (!p->node || p->node == node))
338 return NULL;
339 }
340
341 /* Create and insert publication */
342 p = tipc_publ_create(type, lower, upper, scope, node, port, key);
343 if (!p)
344 goto err;
345 /* Suppose there shouldn't be a huge gap btw publs i.e. >INT_MAX */
346 p->id = sc->publ_cnt++;
347 if (in_own_node(net, node))
348 list_add(&p->local_publ, &sr->local_publ);
349 list_add(&p->all_publ, &sr->all_publ);
350
351 /* Any subscriptions waiting for notification? */
352 list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) {
353 tipc_sub_report_overlap(sub, p->lower, p->upper, TIPC_PUBLISHED,
354 p->port, p->node, p->scope, first);
355 }
356 return p;
357err:
358 pr_warn("Failed to bind to %u,%u,%u, no memory\n", type, lower, upper);
359 return NULL;
360}
361
362/**
363 * tipc_service_remove_publ - remove a publication from a service
364 */
365static struct publication *tipc_service_remove_publ(struct service_range *sr,
366 u32 node, u32 key)
367{
368 struct publication *p;
369
370 list_for_each_entry(p, &sr->all_publ, all_publ) {
371 if (p->key != key || (node && node != p->node))
372 continue;
373 list_del(&p->all_publ);
374 list_del(&p->local_publ);
375 return p;
376 }
377 return NULL;
378}
379
380/**
381 * Code reused: time_after32() for the same purpose
382 */
383#define publication_after(pa, pb) time_after32((pa)->id, (pb)->id)
384static int tipc_publ_sort(void *priv, struct list_head *a,
385 struct list_head *b)
386{
387 struct publication *pa, *pb;
388
389 pa = container_of(a, struct publication, list);
390 pb = container_of(b, struct publication, list);
391 return publication_after(pa, pb);
392}
393
394/**
395 * tipc_service_subscribe - attach a subscription, and optionally
396 * issue the prescribed number of events if there is any service
397 * range overlapping with the requested range
398 */
399static void tipc_service_subscribe(struct tipc_service *service,
400 struct tipc_subscription *sub)
401{
402 struct tipc_subscr *sb = &sub->evt.s;
403 struct publication *p, *first, *tmp;
404 struct list_head publ_list;
405 struct service_range *sr;
406 struct tipc_name_seq ns;
407 u32 filter;
408
409 ns.type = tipc_sub_read(sb, seq.type);
410 ns.lower = tipc_sub_read(sb, seq.lower);
411 ns.upper = tipc_sub_read(sb, seq.upper);
412 filter = tipc_sub_read(sb, filter);
413
414 tipc_sub_get(sub);
415 list_add(&sub->service_list, &service->subscriptions);
416
417 if (filter & TIPC_SUB_NO_STATUS)
418 return;
419
420 INIT_LIST_HEAD(&publ_list);
421 service_range_foreach_match(sr, service, ns.lower, ns.upper) {
422 first = NULL;
423 list_for_each_entry(p, &sr->all_publ, all_publ) {
424 if (filter & TIPC_SUB_PORTS)
425 list_add_tail(&p->list, &publ_list);
426 else if (!first || publication_after(first, p))
427 /* Pick this range's *first* publication */
428 first = p;
429 }
430 if (first)
431 list_add_tail(&first->list, &publ_list);
432 }
433
434 /* Sort the publications before reporting */
435 list_sort(NULL, &publ_list, tipc_publ_sort);
436 list_for_each_entry_safe(p, tmp, &publ_list, list) {
437 tipc_sub_report_overlap(sub, p->lower, p->upper,
438 TIPC_PUBLISHED, p->port, p->node,
439 p->scope, true);
440 list_del_init(&p->list);
441 }
442}
443
444static struct tipc_service *tipc_service_find(struct net *net, u32 type)
445{
446 struct name_table *nt = tipc_name_table(net);
447 struct hlist_head *service_head;
448 struct tipc_service *service;
449
450 service_head = &nt->services[hash(type)];
451 hlist_for_each_entry_rcu(service, service_head, service_list) {
452 if (service->type == type)
453 return service;
454 }
455 return NULL;
456};
457
458struct publication *tipc_nametbl_insert_publ(struct net *net, u32 type,
459 u32 lower, u32 upper,
460 u32 scope, u32 node,
461 u32 port, u32 key)
462{
463 struct name_table *nt = tipc_name_table(net);
464 struct tipc_service *sc;
465 struct publication *p;
466
467 if (scope > TIPC_NODE_SCOPE || lower > upper) {
468 pr_debug("Failed to bind illegal {%u,%u,%u} with scope %u\n",
469 type, lower, upper, scope);
470 return NULL;
471 }
472 sc = tipc_service_find(net, type);
473 if (!sc)
474 sc = tipc_service_create(type, &nt->services[hash(type)]);
475 if (!sc)
476 return NULL;
477
478 spin_lock_bh(&sc->lock);
479 p = tipc_service_insert_publ(net, sc, type, lower, upper,
480 scope, node, port, key);
481 spin_unlock_bh(&sc->lock);
482 return p;
483}
484
485struct publication *tipc_nametbl_remove_publ(struct net *net, u32 type,
486 u32 lower, u32 upper,
487 u32 node, u32 key)
488{
489 struct tipc_service *sc = tipc_service_find(net, type);
490 struct tipc_subscription *sub, *tmp;
491 struct service_range *sr = NULL;
492 struct publication *p = NULL;
493 bool last;
494
495 if (!sc)
496 return NULL;
497
498 spin_lock_bh(&sc->lock);
499 sr = tipc_service_find_range(sc, lower, upper);
500 if (!sr)
501 goto exit;
502 p = tipc_service_remove_publ(sr, node, key);
503 if (!p)
504 goto exit;
505
506 /* Notify any waiting subscriptions */
507 last = list_empty(&sr->all_publ);
508 list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) {
509 tipc_sub_report_overlap(sub, lower, upper, TIPC_WITHDRAWN,
510 p->port, node, p->scope, last);
511 }
512
513 /* Remove service range item if this was its last publication */
514 if (list_empty(&sr->all_publ)) {
515 rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks);
516 kfree(sr);
517 }
518
519 /* Delete service item if this no more publications and subscriptions */
520 if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) {
521 hlist_del_init_rcu(&sc->service_list);
522 kfree_rcu(sc, rcu);
523 }
524exit:
525 spin_unlock_bh(&sc->lock);
526 return p;
527}
528
529/**
530 * tipc_nametbl_translate - perform service instance to socket translation
531 *
532 * On entry, 'dnode' is the search domain used during translation.
533 *
534 * On exit:
535 * - if translation is deferred to another node, leave 'dnode' unchanged and
536 * return 0
537 * - if translation is attempted and succeeds, set 'dnode' to the publishing
538 * node and return the published (non-zero) port number
539 * - if translation is attempted and fails, set 'dnode' to 0 and return 0
540 *
541 * Note that for legacy users (node configured with Z.C.N address format) the
542 * 'closest-first' lookup algorithm must be maintained, i.e., if dnode is 0
543 * we must look in the local binding list first
544 */
545u32 tipc_nametbl_translate(struct net *net, u32 type, u32 instance, u32 *dnode)
546{
547 struct tipc_net *tn = tipc_net(net);
548 bool legacy = tn->legacy_addr_format;
549 u32 self = tipc_own_addr(net);
550 struct service_range *sr;
551 struct tipc_service *sc;
552 struct list_head *list;
553 struct publication *p;
554 u32 port = 0;
555 u32 node = 0;
556
557 if (!tipc_in_scope(legacy, *dnode, self))
558 return 0;
559
560 rcu_read_lock();
561 sc = tipc_service_find(net, type);
562 if (unlikely(!sc))
563 goto exit;
564
565 spin_lock_bh(&sc->lock);
566 service_range_foreach_match(sr, sc, instance, instance) {
567 /* Select lookup algo: local, closest-first or round-robin */
568 if (*dnode == self) {
569 list = &sr->local_publ;
570 if (list_empty(list))
571 continue;
572 p = list_first_entry(list, struct publication,
573 local_publ);
574 list_move_tail(&p->local_publ, &sr->local_publ);
575 } else if (legacy && !*dnode && !list_empty(&sr->local_publ)) {
576 list = &sr->local_publ;
577 p = list_first_entry(list, struct publication,
578 local_publ);
579 list_move_tail(&p->local_publ, &sr->local_publ);
580 } else {
581 list = &sr->all_publ;
582 p = list_first_entry(list, struct publication,
583 all_publ);
584 list_move_tail(&p->all_publ, &sr->all_publ);
585 }
586 port = p->port;
587 node = p->node;
588 /* Todo: as for legacy, pick the first matching range only, a
589 * "true" round-robin will be performed as needed.
590 */
591 break;
592 }
593 spin_unlock_bh(&sc->lock);
594
595exit:
596 rcu_read_unlock();
597 *dnode = node;
598 return port;
599}
600
601bool tipc_nametbl_lookup(struct net *net, u32 type, u32 instance, u32 scope,
602 struct list_head *dsts, int *dstcnt, u32 exclude,
603 bool all)
604{
605 u32 self = tipc_own_addr(net);
606 struct service_range *sr;
607 struct tipc_service *sc;
608 struct publication *p;
609
610 *dstcnt = 0;
611 rcu_read_lock();
612 sc = tipc_service_find(net, type);
613 if (unlikely(!sc))
614 goto exit;
615
616 spin_lock_bh(&sc->lock);
617
618 /* Todo: a full search i.e. service_range_foreach_match() instead? */
619 sr = service_range_match_first(sc->ranges.rb_node, instance, instance);
620 if (!sr)
621 goto no_match;
622
623 list_for_each_entry(p, &sr->all_publ, all_publ) {
624 if (p->scope != scope)
625 continue;
626 if (p->port == exclude && p->node == self)
627 continue;
628 tipc_dest_push(dsts, p->node, p->port);
629 (*dstcnt)++;
630 if (all)
631 continue;
632 list_move_tail(&p->all_publ, &sr->all_publ);
633 break;
634 }
635no_match:
636 spin_unlock_bh(&sc->lock);
637exit:
638 rcu_read_unlock();
639 return !list_empty(dsts);
640}
641
642void tipc_nametbl_mc_lookup(struct net *net, u32 type, u32 lower, u32 upper,
643 u32 scope, bool exact, struct list_head *dports)
644{
645 struct service_range *sr;
646 struct tipc_service *sc;
647 struct publication *p;
648
649 rcu_read_lock();
650 sc = tipc_service_find(net, type);
651 if (!sc)
652 goto exit;
653
654 spin_lock_bh(&sc->lock);
655 service_range_foreach_match(sr, sc, lower, upper) {
656 list_for_each_entry(p, &sr->local_publ, local_publ) {
657 if (p->scope == scope || (!exact && p->scope < scope))
658 tipc_dest_push(dports, 0, p->port);
659 }
660 }
661 spin_unlock_bh(&sc->lock);
662exit:
663 rcu_read_unlock();
664}
665
666/* tipc_nametbl_lookup_dst_nodes - find broadcast destination nodes
667 * - Creates list of nodes that overlap the given multicast address
668 * - Determines if any node local destinations overlap
669 */
670void tipc_nametbl_lookup_dst_nodes(struct net *net, u32 type, u32 lower,
671 u32 upper, struct tipc_nlist *nodes)
672{
673 struct service_range *sr;
674 struct tipc_service *sc;
675 struct publication *p;
676
677 rcu_read_lock();
678 sc = tipc_service_find(net, type);
679 if (!sc)
680 goto exit;
681
682 spin_lock_bh(&sc->lock);
683 service_range_foreach_match(sr, sc, lower, upper) {
684 list_for_each_entry(p, &sr->all_publ, all_publ) {
685 tipc_nlist_add(nodes, p->node);
686 }
687 }
688 spin_unlock_bh(&sc->lock);
689exit:
690 rcu_read_unlock();
691}
692
693/* tipc_nametbl_build_group - build list of communication group members
694 */
695void tipc_nametbl_build_group(struct net *net, struct tipc_group *grp,
696 u32 type, u32 scope)
697{
698 struct service_range *sr;
699 struct tipc_service *sc;
700 struct publication *p;
701 struct rb_node *n;
702
703 rcu_read_lock();
704 sc = tipc_service_find(net, type);
705 if (!sc)
706 goto exit;
707
708 spin_lock_bh(&sc->lock);
709 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
710 sr = container_of(n, struct service_range, tree_node);
711 list_for_each_entry(p, &sr->all_publ, all_publ) {
712 if (p->scope != scope)
713 continue;
714 tipc_group_add_member(grp, p->node, p->port, p->lower);
715 }
716 }
717 spin_unlock_bh(&sc->lock);
718exit:
719 rcu_read_unlock();
720}
721
722/* tipc_nametbl_publish - add service binding to name table
723 */
724struct publication *tipc_nametbl_publish(struct net *net, u32 type, u32 lower,
725 u32 upper, u32 scope, u32 port,
726 u32 key)
727{
728 struct name_table *nt = tipc_name_table(net);
729 struct tipc_net *tn = tipc_net(net);
730 struct publication *p = NULL;
731 struct sk_buff *skb = NULL;
732 u32 rc_dests;
733
734 spin_lock_bh(&tn->nametbl_lock);
735
736 if (nt->local_publ_count >= TIPC_MAX_PUBL) {
737 pr_warn("Bind failed, max limit %u reached\n", TIPC_MAX_PUBL);
738 goto exit;
739 }
740
741 p = tipc_nametbl_insert_publ(net, type, lower, upper, scope,
742 tipc_own_addr(net), port, key);
743 if (p) {
744 nt->local_publ_count++;
745 skb = tipc_named_publish(net, p);
746 }
747 rc_dests = nt->rc_dests;
748exit:
749 spin_unlock_bh(&tn->nametbl_lock);
750
751 if (skb)
752 tipc_node_broadcast(net, skb, rc_dests);
753 return p;
754
755}
756
757/**
758 * tipc_nametbl_withdraw - withdraw a service binding
759 */
760int tipc_nametbl_withdraw(struct net *net, u32 type, u32 lower,
761 u32 upper, u32 key)
762{
763 struct name_table *nt = tipc_name_table(net);
764 struct tipc_net *tn = tipc_net(net);
765 u32 self = tipc_own_addr(net);
766 struct sk_buff *skb = NULL;
767 struct publication *p;
768 u32 rc_dests;
769
770 spin_lock_bh(&tn->nametbl_lock);
771
772 p = tipc_nametbl_remove_publ(net, type, lower, upper, self, key);
773 if (p) {
774 nt->local_publ_count--;
775 skb = tipc_named_withdraw(net, p);
776 list_del_init(&p->binding_sock);
777 kfree_rcu(p, rcu);
778 } else {
779 pr_err("Failed to remove local publication {%u,%u,%u}/%u\n",
780 type, lower, upper, key);
781 }
782 rc_dests = nt->rc_dests;
783 spin_unlock_bh(&tn->nametbl_lock);
784
785 if (skb) {
786 tipc_node_broadcast(net, skb, rc_dests);
787 return 1;
788 }
789 return 0;
790}
791
792/**
793 * tipc_nametbl_subscribe - add a subscription object to the name table
794 */
795bool tipc_nametbl_subscribe(struct tipc_subscription *sub)
796{
797 struct name_table *nt = tipc_name_table(sub->net);
798 struct tipc_net *tn = tipc_net(sub->net);
799 struct tipc_subscr *s = &sub->evt.s;
800 u32 type = tipc_sub_read(s, seq.type);
801 struct tipc_service *sc;
802 bool res = true;
803
804 spin_lock_bh(&tn->nametbl_lock);
805 sc = tipc_service_find(sub->net, type);
806 if (!sc)
807 sc = tipc_service_create(type, &nt->services[hash(type)]);
808 if (sc) {
809 spin_lock_bh(&sc->lock);
810 tipc_service_subscribe(sc, sub);
811 spin_unlock_bh(&sc->lock);
812 } else {
813 pr_warn("Failed to subscribe for {%u,%u,%u}\n", type,
814 tipc_sub_read(s, seq.lower),
815 tipc_sub_read(s, seq.upper));
816 res = false;
817 }
818 spin_unlock_bh(&tn->nametbl_lock);
819 return res;
820}
821
822/**
823 * tipc_nametbl_unsubscribe - remove a subscription object from name table
824 */
825void tipc_nametbl_unsubscribe(struct tipc_subscription *sub)
826{
827 struct tipc_net *tn = tipc_net(sub->net);
828 struct tipc_subscr *s = &sub->evt.s;
829 u32 type = tipc_sub_read(s, seq.type);
830 struct tipc_service *sc;
831
832 spin_lock_bh(&tn->nametbl_lock);
833 sc = tipc_service_find(sub->net, type);
834 if (!sc)
835 goto exit;
836
837 spin_lock_bh(&sc->lock);
838 list_del_init(&sub->service_list);
839 tipc_sub_put(sub);
840
841 /* Delete service item if no more publications and subscriptions */
842 if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) {
843 hlist_del_init_rcu(&sc->service_list);
844 kfree_rcu(sc, rcu);
845 }
846 spin_unlock_bh(&sc->lock);
847exit:
848 spin_unlock_bh(&tn->nametbl_lock);
849}
850
851int tipc_nametbl_init(struct net *net)
852{
853 struct tipc_net *tn = tipc_net(net);
854 struct name_table *nt;
855 int i;
856
857 nt = kzalloc(sizeof(*nt), GFP_KERNEL);
858 if (!nt)
859 return -ENOMEM;
860
861 for (i = 0; i < TIPC_NAMETBL_SIZE; i++)
862 INIT_HLIST_HEAD(&nt->services[i]);
863
864 INIT_LIST_HEAD(&nt->node_scope);
865 INIT_LIST_HEAD(&nt->cluster_scope);
866 rwlock_init(&nt->cluster_scope_lock);
867 tn->nametbl = nt;
868 spin_lock_init(&tn->nametbl_lock);
869 return 0;
870}
871
872/**
873 * tipc_service_delete - purge all publications for a service and delete it
874 */
875static void tipc_service_delete(struct net *net, struct tipc_service *sc)
876{
877 struct service_range *sr, *tmpr;
878 struct publication *p, *tmp;
879
880 spin_lock_bh(&sc->lock);
881 rbtree_postorder_for_each_entry_safe(sr, tmpr, &sc->ranges, tree_node) {
882 list_for_each_entry_safe(p, tmp, &sr->all_publ, all_publ) {
883 tipc_service_remove_publ(sr, p->node, p->key);
884 kfree_rcu(p, rcu);
885 }
886 rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks);
887 kfree(sr);
888 }
889 hlist_del_init_rcu(&sc->service_list);
890 spin_unlock_bh(&sc->lock);
891 kfree_rcu(sc, rcu);
892}
893
894void tipc_nametbl_stop(struct net *net)
895{
896 struct name_table *nt = tipc_name_table(net);
897 struct tipc_net *tn = tipc_net(net);
898 struct hlist_head *service_head;
899 struct tipc_service *service;
900 u32 i;
901
902 /* Verify name table is empty and purge any lingering
903 * publications, then release the name table
904 */
905 spin_lock_bh(&tn->nametbl_lock);
906 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) {
907 if (hlist_empty(&nt->services[i]))
908 continue;
909 service_head = &nt->services[i];
910 hlist_for_each_entry_rcu(service, service_head, service_list) {
911 tipc_service_delete(net, service);
912 }
913 }
914 spin_unlock_bh(&tn->nametbl_lock);
915
916 synchronize_net();
917 kfree(nt);
918}
919
920static int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg,
921 struct tipc_service *service,
922 struct service_range *sr,
923 u32 *last_key)
924{
925 struct publication *p;
926 struct nlattr *attrs;
927 struct nlattr *b;
928 void *hdr;
929
930 if (*last_key) {
931 list_for_each_entry(p, &sr->all_publ, all_publ)
932 if (p->key == *last_key)
933 break;
934 if (p->key != *last_key)
935 return -EPIPE;
936 } else {
937 p = list_first_entry(&sr->all_publ,
938 struct publication,
939 all_publ);
940 }
941
942 list_for_each_entry_from(p, &sr->all_publ, all_publ) {
943 *last_key = p->key;
944
945 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq,
946 &tipc_genl_family, NLM_F_MULTI,
947 TIPC_NL_NAME_TABLE_GET);
948 if (!hdr)
949 return -EMSGSIZE;
950
951 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE);
952 if (!attrs)
953 goto msg_full;
954
955 b = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE_PUBL);
956 if (!b)
957 goto attr_msg_full;
958
959 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, service->type))
960 goto publ_msg_full;
961 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sr->lower))
962 goto publ_msg_full;
963 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sr->upper))
964 goto publ_msg_full;
965 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope))
966 goto publ_msg_full;
967 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->node))
968 goto publ_msg_full;
969 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->port))
970 goto publ_msg_full;
971 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key))
972 goto publ_msg_full;
973
974 nla_nest_end(msg->skb, b);
975 nla_nest_end(msg->skb, attrs);
976 genlmsg_end(msg->skb, hdr);
977 }
978 *last_key = 0;
979
980 return 0;
981
982publ_msg_full:
983 nla_nest_cancel(msg->skb, b);
984attr_msg_full:
985 nla_nest_cancel(msg->skb, attrs);
986msg_full:
987 genlmsg_cancel(msg->skb, hdr);
988
989 return -EMSGSIZE;
990}
991
992static int __tipc_nl_service_range_list(struct tipc_nl_msg *msg,
993 struct tipc_service *sc,
994 u32 *last_lower, u32 *last_key)
995{
996 struct service_range *sr;
997 struct rb_node *n;
998 int err;
999
1000 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
1001 sr = container_of(n, struct service_range, tree_node);
1002 if (sr->lower < *last_lower)
1003 continue;
1004 err = __tipc_nl_add_nametable_publ(msg, sc, sr, last_key);
1005 if (err) {
1006 *last_lower = sr->lower;
1007 return err;
1008 }
1009 }
1010 *last_lower = 0;
1011 return 0;
1012}
1013
1014static int tipc_nl_service_list(struct net *net, struct tipc_nl_msg *msg,
1015 u32 *last_type, u32 *last_lower, u32 *last_key)
1016{
1017 struct tipc_net *tn = tipc_net(net);
1018 struct tipc_service *service = NULL;
1019 struct hlist_head *head;
1020 int err;
1021 int i;
1022
1023 if (*last_type)
1024 i = hash(*last_type);
1025 else
1026 i = 0;
1027
1028 for (; i < TIPC_NAMETBL_SIZE; i++) {
1029 head = &tn->nametbl->services[i];
1030
1031 if (*last_type ||
1032 (!i && *last_key && (*last_lower == *last_key))) {
1033 service = tipc_service_find(net, *last_type);
1034 if (!service)
1035 return -EPIPE;
1036 } else {
1037 hlist_for_each_entry_rcu(service, head, service_list)
1038 break;
1039 if (!service)
1040 continue;
1041 }
1042
1043 hlist_for_each_entry_from_rcu(service, service_list) {
1044 spin_lock_bh(&service->lock);
1045 err = __tipc_nl_service_range_list(msg, service,
1046 last_lower,
1047 last_key);
1048
1049 if (err) {
1050 *last_type = service->type;
1051 spin_unlock_bh(&service->lock);
1052 return err;
1053 }
1054 spin_unlock_bh(&service->lock);
1055 }
1056 *last_type = 0;
1057 }
1058 return 0;
1059}
1060
1061int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb)
1062{
1063 struct net *net = sock_net(skb->sk);
1064 u32 last_type = cb->args[0];
1065 u32 last_lower = cb->args[1];
1066 u32 last_key = cb->args[2];
1067 int done = cb->args[3];
1068 struct tipc_nl_msg msg;
1069 int err;
1070
1071 if (done)
1072 return 0;
1073
1074 msg.skb = skb;
1075 msg.portid = NETLINK_CB(cb->skb).portid;
1076 msg.seq = cb->nlh->nlmsg_seq;
1077
1078 rcu_read_lock();
1079 err = tipc_nl_service_list(net, &msg, &last_type,
1080 &last_lower, &last_key);
1081 if (!err) {
1082 done = 1;
1083 } else if (err != -EMSGSIZE) {
1084 /* We never set seq or call nl_dump_check_consistent() this
1085 * means that setting prev_seq here will cause the consistence
1086 * check to fail in the netlink callback handler. Resulting in
1087 * the NLMSG_DONE message having the NLM_F_DUMP_INTR flag set if
1088 * we got an error.
1089 */
1090 cb->prev_seq = 1;
1091 }
1092 rcu_read_unlock();
1093
1094 cb->args[0] = last_type;
1095 cb->args[1] = last_lower;
1096 cb->args[2] = last_key;
1097 cb->args[3] = done;
1098
1099 return skb->len;
1100}
1101
1102struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port)
1103{
1104 struct tipc_dest *dst;
1105
1106 list_for_each_entry(dst, l, list) {
1107 if (dst->node == node && dst->port == port)
1108 return dst;
1109 }
1110 return NULL;
1111}
1112
1113bool tipc_dest_push(struct list_head *l, u32 node, u32 port)
1114{
1115 struct tipc_dest *dst;
1116
1117 if (tipc_dest_find(l, node, port))
1118 return false;
1119
1120 dst = kmalloc(sizeof(*dst), GFP_ATOMIC);
1121 if (unlikely(!dst))
1122 return false;
1123 dst->node = node;
1124 dst->port = port;
1125 list_add(&dst->list, l);
1126 return true;
1127}
1128
1129bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port)
1130{
1131 struct tipc_dest *dst;
1132
1133 if (list_empty(l))
1134 return false;
1135 dst = list_first_entry(l, typeof(*dst), list);
1136 if (port)
1137 *port = dst->port;
1138 if (node)
1139 *node = dst->node;
1140 list_del(&dst->list);
1141 kfree(dst);
1142 return true;
1143}
1144
1145bool tipc_dest_del(struct list_head *l, u32 node, u32 port)
1146{
1147 struct tipc_dest *dst;
1148
1149 dst = tipc_dest_find(l, node, port);
1150 if (!dst)
1151 return false;
1152 list_del(&dst->list);
1153 kfree(dst);
1154 return true;
1155}
1156
1157void tipc_dest_list_purge(struct list_head *l)
1158{
1159 struct tipc_dest *dst, *tmp;
1160
1161 list_for_each_entry_safe(dst, tmp, l, list) {
1162 list_del(&dst->list);
1163 kfree(dst);
1164 }
1165}
1166
1167int tipc_dest_list_len(struct list_head *l)
1168{
1169 struct tipc_dest *dst;
1170 int i = 0;
1171
1172 list_for_each_entry(dst, l, list) {
1173 i++;
1174 }
1175 return i;
1176}
1/*
2 * net/tipc/name_table.c: TIPC name table code
3 *
4 * Copyright (c) 2000-2006, 2014-2018, Ericsson AB
5 * Copyright (c) 2004-2008, 2010-2014, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include <net/sock.h>
38#include "core.h"
39#include "netlink.h"
40#include "name_table.h"
41#include "name_distr.h"
42#include "subscr.h"
43#include "bcast.h"
44#include "addr.h"
45#include "node.h"
46#include "group.h"
47
48/**
49 * struct service_range - container for all bindings of a service range
50 * @lower: service range lower bound
51 * @upper: service range upper bound
52 * @tree_node: member of service range RB tree
53 * @local_publ: list of identical publications made from this node
54 * Used by closest_first lookup and multicast lookup algorithm
55 * @all_publ: all publications identical to this one, whatever node and scope
56 * Used by round-robin lookup algorithm
57 */
58struct service_range {
59 u32 lower;
60 u32 upper;
61 struct rb_node tree_node;
62 struct list_head local_publ;
63 struct list_head all_publ;
64};
65
66/**
67 * struct tipc_service - container for all published instances of a service type
68 * @type: 32 bit 'type' value for service
69 * @ranges: rb tree containing all service ranges for this service
70 * @service_list: links to adjacent name ranges in hash chain
71 * @subscriptions: list of subscriptions for this service type
72 * @lock: spinlock controlling access to pertaining service ranges/publications
73 * @rcu: RCU callback head used for deferred freeing
74 */
75struct tipc_service {
76 u32 type;
77 struct rb_root ranges;
78 struct hlist_node service_list;
79 struct list_head subscriptions;
80 spinlock_t lock; /* Covers service range list */
81 struct rcu_head rcu;
82};
83
84static int hash(int x)
85{
86 return x & (TIPC_NAMETBL_SIZE - 1);
87}
88
89/**
90 * tipc_publ_create - create a publication structure
91 */
92static struct publication *tipc_publ_create(u32 type, u32 lower, u32 upper,
93 u32 scope, u32 node, u32 port,
94 u32 key)
95{
96 struct publication *publ = kzalloc(sizeof(*publ), GFP_ATOMIC);
97
98 if (!publ)
99 return NULL;
100
101 publ->type = type;
102 publ->lower = lower;
103 publ->upper = upper;
104 publ->scope = scope;
105 publ->node = node;
106 publ->port = port;
107 publ->key = key;
108 INIT_LIST_HEAD(&publ->binding_sock);
109 INIT_LIST_HEAD(&publ->binding_node);
110 INIT_LIST_HEAD(&publ->local_publ);
111 INIT_LIST_HEAD(&publ->all_publ);
112 return publ;
113}
114
115/**
116 * tipc_service_create - create a service structure for the specified 'type'
117 *
118 * Allocates a single range structure and sets it to all 0's.
119 */
120static struct tipc_service *tipc_service_create(u32 type, struct hlist_head *hd)
121{
122 struct tipc_service *service = kzalloc(sizeof(*service), GFP_ATOMIC);
123
124 if (!service) {
125 pr_warn("Service creation failed, no memory\n");
126 return NULL;
127 }
128
129 spin_lock_init(&service->lock);
130 service->type = type;
131 service->ranges = RB_ROOT;
132 INIT_HLIST_NODE(&service->service_list);
133 INIT_LIST_HEAD(&service->subscriptions);
134 hlist_add_head_rcu(&service->service_list, hd);
135 return service;
136}
137
138/**
139 * tipc_service_find_range - find service range matching a service instance
140 *
141 * Very time-critical, so binary search through range rb tree
142 */
143static struct service_range *tipc_service_find_range(struct tipc_service *sc,
144 u32 instance)
145{
146 struct rb_node *n = sc->ranges.rb_node;
147 struct service_range *sr;
148
149 while (n) {
150 sr = container_of(n, struct service_range, tree_node);
151 if (sr->lower > instance)
152 n = n->rb_left;
153 else if (sr->upper < instance)
154 n = n->rb_right;
155 else
156 return sr;
157 }
158 return NULL;
159}
160
161static struct service_range *tipc_service_create_range(struct tipc_service *sc,
162 u32 lower, u32 upper)
163{
164 struct rb_node **n, *parent = NULL;
165 struct service_range *sr, *tmp;
166
167 n = &sc->ranges.rb_node;
168 while (*n) {
169 tmp = container_of(*n, struct service_range, tree_node);
170 parent = *n;
171 tmp = container_of(parent, struct service_range, tree_node);
172 if (lower < tmp->lower)
173 n = &(*n)->rb_left;
174 else if (lower > tmp->lower)
175 n = &(*n)->rb_right;
176 else if (upper < tmp->upper)
177 n = &(*n)->rb_left;
178 else if (upper > tmp->upper)
179 n = &(*n)->rb_right;
180 else
181 return tmp;
182 }
183 sr = kzalloc(sizeof(*sr), GFP_ATOMIC);
184 if (!sr)
185 return NULL;
186 sr->lower = lower;
187 sr->upper = upper;
188 INIT_LIST_HEAD(&sr->local_publ);
189 INIT_LIST_HEAD(&sr->all_publ);
190 rb_link_node(&sr->tree_node, parent, n);
191 rb_insert_color(&sr->tree_node, &sc->ranges);
192 return sr;
193}
194
195static struct publication *tipc_service_insert_publ(struct net *net,
196 struct tipc_service *sc,
197 u32 type, u32 lower,
198 u32 upper, u32 scope,
199 u32 node, u32 port,
200 u32 key)
201{
202 struct tipc_subscription *sub, *tmp;
203 struct service_range *sr;
204 struct publication *p;
205 bool first = false;
206
207 sr = tipc_service_create_range(sc, lower, upper);
208 if (!sr)
209 goto err;
210
211 first = list_empty(&sr->all_publ);
212
213 /* Return if the publication already exists */
214 list_for_each_entry(p, &sr->all_publ, all_publ) {
215 if (p->key == key && (!p->node || p->node == node))
216 return NULL;
217 }
218
219 /* Create and insert publication */
220 p = tipc_publ_create(type, lower, upper, scope, node, port, key);
221 if (!p)
222 goto err;
223 if (in_own_node(net, node))
224 list_add(&p->local_publ, &sr->local_publ);
225 list_add(&p->all_publ, &sr->all_publ);
226
227 /* Any subscriptions waiting for notification? */
228 list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) {
229 tipc_sub_report_overlap(sub, p->lower, p->upper, TIPC_PUBLISHED,
230 p->port, p->node, p->scope, first);
231 }
232 return p;
233err:
234 pr_warn("Failed to bind to %u,%u,%u, no memory\n", type, lower, upper);
235 return NULL;
236}
237
238/**
239 * tipc_service_remove_publ - remove a publication from a service
240 */
241static struct publication *tipc_service_remove_publ(struct net *net,
242 struct tipc_service *sc,
243 u32 lower, u32 upper,
244 u32 node, u32 key,
245 struct service_range **rng)
246{
247 struct tipc_subscription *sub, *tmp;
248 struct service_range *sr;
249 struct publication *p;
250 bool found = false;
251 bool last = false;
252 struct rb_node *n;
253
254 sr = tipc_service_find_range(sc, lower);
255 if (!sr)
256 return NULL;
257
258 /* Find exact matching service range */
259 for (n = &sr->tree_node; n; n = rb_next(n)) {
260 sr = container_of(n, struct service_range, tree_node);
261 if (sr->upper == upper)
262 break;
263 }
264 if (!n || sr->lower != lower || sr->upper != upper)
265 return NULL;
266
267 /* Find publication, if it exists */
268 list_for_each_entry(p, &sr->all_publ, all_publ) {
269 if (p->key != key || (node && node != p->node))
270 continue;
271 found = true;
272 break;
273 }
274 if (!found)
275 return NULL;
276
277 list_del(&p->all_publ);
278 list_del(&p->local_publ);
279 if (list_empty(&sr->all_publ))
280 last = true;
281
282 /* Notify any waiting subscriptions */
283 list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) {
284 tipc_sub_report_overlap(sub, p->lower, p->upper, TIPC_WITHDRAWN,
285 p->port, p->node, p->scope, last);
286 }
287 *rng = sr;
288 return p;
289}
290
291/**
292 * tipc_service_subscribe - attach a subscription, and optionally
293 * issue the prescribed number of events if there is any service
294 * range overlapping with the requested range
295 */
296static void tipc_service_subscribe(struct tipc_service *service,
297 struct tipc_subscription *sub)
298{
299 struct tipc_subscr *sb = &sub->evt.s;
300 struct service_range *sr;
301 struct tipc_name_seq ns;
302 struct publication *p;
303 struct rb_node *n;
304 bool first;
305
306 ns.type = tipc_sub_read(sb, seq.type);
307 ns.lower = tipc_sub_read(sb, seq.lower);
308 ns.upper = tipc_sub_read(sb, seq.upper);
309
310 tipc_sub_get(sub);
311 list_add(&sub->service_list, &service->subscriptions);
312
313 if (tipc_sub_read(sb, filter) & TIPC_SUB_NO_STATUS)
314 return;
315
316 for (n = rb_first(&service->ranges); n; n = rb_next(n)) {
317 sr = container_of(n, struct service_range, tree_node);
318 if (sr->lower > ns.upper)
319 break;
320 if (!tipc_sub_check_overlap(&ns, sr->lower, sr->upper))
321 continue;
322 first = true;
323
324 list_for_each_entry(p, &sr->all_publ, all_publ) {
325 tipc_sub_report_overlap(sub, sr->lower, sr->upper,
326 TIPC_PUBLISHED, p->port,
327 p->node, p->scope, first);
328 first = false;
329 }
330 }
331}
332
333static struct tipc_service *tipc_service_find(struct net *net, u32 type)
334{
335 struct name_table *nt = tipc_name_table(net);
336 struct hlist_head *service_head;
337 struct tipc_service *service;
338
339 service_head = &nt->services[hash(type)];
340 hlist_for_each_entry_rcu(service, service_head, service_list) {
341 if (service->type == type)
342 return service;
343 }
344 return NULL;
345};
346
347struct publication *tipc_nametbl_insert_publ(struct net *net, u32 type,
348 u32 lower, u32 upper,
349 u32 scope, u32 node,
350 u32 port, u32 key)
351{
352 struct name_table *nt = tipc_name_table(net);
353 struct tipc_service *sc;
354 struct publication *p;
355
356 if (scope > TIPC_NODE_SCOPE || lower > upper) {
357 pr_debug("Failed to bind illegal {%u,%u,%u} with scope %u\n",
358 type, lower, upper, scope);
359 return NULL;
360 }
361 sc = tipc_service_find(net, type);
362 if (!sc)
363 sc = tipc_service_create(type, &nt->services[hash(type)]);
364 if (!sc)
365 return NULL;
366
367 spin_lock_bh(&sc->lock);
368 p = tipc_service_insert_publ(net, sc, type, lower, upper,
369 scope, node, port, key);
370 spin_unlock_bh(&sc->lock);
371 return p;
372}
373
374struct publication *tipc_nametbl_remove_publ(struct net *net, u32 type,
375 u32 lower, u32 upper,
376 u32 node, u32 key)
377{
378 struct tipc_service *sc = tipc_service_find(net, type);
379 struct service_range *sr = NULL;
380 struct publication *p = NULL;
381
382 if (!sc)
383 return NULL;
384
385 spin_lock_bh(&sc->lock);
386 p = tipc_service_remove_publ(net, sc, lower, upper, node, key, &sr);
387
388 /* Remove service range item if this was its last publication */
389 if (sr && list_empty(&sr->all_publ)) {
390 rb_erase(&sr->tree_node, &sc->ranges);
391 kfree(sr);
392 }
393
394 /* Delete service item if this no more publications and subscriptions */
395 if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) {
396 hlist_del_init_rcu(&sc->service_list);
397 kfree_rcu(sc, rcu);
398 }
399 spin_unlock_bh(&sc->lock);
400 return p;
401}
402
403/**
404 * tipc_nametbl_translate - perform service instance to socket translation
405 *
406 * On entry, 'dnode' is the search domain used during translation.
407 *
408 * On exit:
409 * - if translation is deferred to another node, leave 'dnode' unchanged and
410 * return 0
411 * - if translation is attempted and succeeds, set 'dnode' to the publishing
412 * node and return the published (non-zero) port number
413 * - if translation is attempted and fails, set 'dnode' to 0 and return 0
414 *
415 * Note that for legacy users (node configured with Z.C.N address format) the
416 * 'closest-first' lookup algorithm must be maintained, i.e., if dnode is 0
417 * we must look in the local binding list first
418 */
419u32 tipc_nametbl_translate(struct net *net, u32 type, u32 instance, u32 *dnode)
420{
421 struct tipc_net *tn = tipc_net(net);
422 bool legacy = tn->legacy_addr_format;
423 u32 self = tipc_own_addr(net);
424 struct service_range *sr;
425 struct tipc_service *sc;
426 struct list_head *list;
427 struct publication *p;
428 u32 port = 0;
429 u32 node = 0;
430
431 if (!tipc_in_scope(legacy, *dnode, self))
432 return 0;
433
434 rcu_read_lock();
435 sc = tipc_service_find(net, type);
436 if (unlikely(!sc))
437 goto not_found;
438
439 spin_lock_bh(&sc->lock);
440 sr = tipc_service_find_range(sc, instance);
441 if (unlikely(!sr))
442 goto no_match;
443
444 /* Select lookup algorithm: local, closest-first or round-robin */
445 if (*dnode == self) {
446 list = &sr->local_publ;
447 if (list_empty(list))
448 goto no_match;
449 p = list_first_entry(list, struct publication, local_publ);
450 list_move_tail(&p->local_publ, &sr->local_publ);
451 } else if (legacy && !*dnode && !list_empty(&sr->local_publ)) {
452 list = &sr->local_publ;
453 p = list_first_entry(list, struct publication, local_publ);
454 list_move_tail(&p->local_publ, &sr->local_publ);
455 } else {
456 list = &sr->all_publ;
457 p = list_first_entry(list, struct publication, all_publ);
458 list_move_tail(&p->all_publ, &sr->all_publ);
459 }
460 port = p->port;
461 node = p->node;
462no_match:
463 spin_unlock_bh(&sc->lock);
464not_found:
465 rcu_read_unlock();
466 *dnode = node;
467 return port;
468}
469
470bool tipc_nametbl_lookup(struct net *net, u32 type, u32 instance, u32 scope,
471 struct list_head *dsts, int *dstcnt, u32 exclude,
472 bool all)
473{
474 u32 self = tipc_own_addr(net);
475 struct service_range *sr;
476 struct tipc_service *sc;
477 struct publication *p;
478
479 *dstcnt = 0;
480 rcu_read_lock();
481 sc = tipc_service_find(net, type);
482 if (unlikely(!sc))
483 goto exit;
484
485 spin_lock_bh(&sc->lock);
486
487 sr = tipc_service_find_range(sc, instance);
488 if (!sr)
489 goto no_match;
490
491 list_for_each_entry(p, &sr->all_publ, all_publ) {
492 if (p->scope != scope)
493 continue;
494 if (p->port == exclude && p->node == self)
495 continue;
496 tipc_dest_push(dsts, p->node, p->port);
497 (*dstcnt)++;
498 if (all)
499 continue;
500 list_move_tail(&p->all_publ, &sr->all_publ);
501 break;
502 }
503no_match:
504 spin_unlock_bh(&sc->lock);
505exit:
506 rcu_read_unlock();
507 return !list_empty(dsts);
508}
509
510void tipc_nametbl_mc_lookup(struct net *net, u32 type, u32 lower, u32 upper,
511 u32 scope, bool exact, struct list_head *dports)
512{
513 struct service_range *sr;
514 struct tipc_service *sc;
515 struct publication *p;
516 struct rb_node *n;
517
518 rcu_read_lock();
519 sc = tipc_service_find(net, type);
520 if (!sc)
521 goto exit;
522
523 spin_lock_bh(&sc->lock);
524
525 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
526 sr = container_of(n, struct service_range, tree_node);
527 if (sr->upper < lower)
528 continue;
529 if (sr->lower > upper)
530 break;
531 list_for_each_entry(p, &sr->local_publ, local_publ) {
532 if (p->scope == scope || (!exact && p->scope < scope))
533 tipc_dest_push(dports, 0, p->port);
534 }
535 }
536 spin_unlock_bh(&sc->lock);
537exit:
538 rcu_read_unlock();
539}
540
541/* tipc_nametbl_lookup_dst_nodes - find broadcast destination nodes
542 * - Creates list of nodes that overlap the given multicast address
543 * - Determines if any node local destinations overlap
544 */
545void tipc_nametbl_lookup_dst_nodes(struct net *net, u32 type, u32 lower,
546 u32 upper, struct tipc_nlist *nodes)
547{
548 struct service_range *sr;
549 struct tipc_service *sc;
550 struct publication *p;
551 struct rb_node *n;
552
553 rcu_read_lock();
554 sc = tipc_service_find(net, type);
555 if (!sc)
556 goto exit;
557
558 spin_lock_bh(&sc->lock);
559
560 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
561 sr = container_of(n, struct service_range, tree_node);
562 if (sr->upper < lower)
563 continue;
564 if (sr->lower > upper)
565 break;
566 list_for_each_entry(p, &sr->all_publ, all_publ) {
567 tipc_nlist_add(nodes, p->node);
568 }
569 }
570 spin_unlock_bh(&sc->lock);
571exit:
572 rcu_read_unlock();
573}
574
575/* tipc_nametbl_build_group - build list of communication group members
576 */
577void tipc_nametbl_build_group(struct net *net, struct tipc_group *grp,
578 u32 type, u32 scope)
579{
580 struct service_range *sr;
581 struct tipc_service *sc;
582 struct publication *p;
583 struct rb_node *n;
584
585 rcu_read_lock();
586 sc = tipc_service_find(net, type);
587 if (!sc)
588 goto exit;
589
590 spin_lock_bh(&sc->lock);
591 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
592 sr = container_of(n, struct service_range, tree_node);
593 list_for_each_entry(p, &sr->all_publ, all_publ) {
594 if (p->scope != scope)
595 continue;
596 tipc_group_add_member(grp, p->node, p->port, p->lower);
597 }
598 }
599 spin_unlock_bh(&sc->lock);
600exit:
601 rcu_read_unlock();
602}
603
604/* tipc_nametbl_publish - add service binding to name table
605 */
606struct publication *tipc_nametbl_publish(struct net *net, u32 type, u32 lower,
607 u32 upper, u32 scope, u32 port,
608 u32 key)
609{
610 struct name_table *nt = tipc_name_table(net);
611 struct tipc_net *tn = tipc_net(net);
612 struct publication *p = NULL;
613 struct sk_buff *skb = NULL;
614
615 spin_lock_bh(&tn->nametbl_lock);
616
617 if (nt->local_publ_count >= TIPC_MAX_PUBL) {
618 pr_warn("Bind failed, max limit %u reached\n", TIPC_MAX_PUBL);
619 goto exit;
620 }
621
622 p = tipc_nametbl_insert_publ(net, type, lower, upper, scope,
623 tipc_own_addr(net), port, key);
624 if (p) {
625 nt->local_publ_count++;
626 skb = tipc_named_publish(net, p);
627 }
628exit:
629 spin_unlock_bh(&tn->nametbl_lock);
630
631 if (skb)
632 tipc_node_broadcast(net, skb);
633 return p;
634}
635
636/**
637 * tipc_nametbl_withdraw - withdraw a service binding
638 */
639int tipc_nametbl_withdraw(struct net *net, u32 type, u32 lower,
640 u32 upper, u32 key)
641{
642 struct name_table *nt = tipc_name_table(net);
643 struct tipc_net *tn = tipc_net(net);
644 u32 self = tipc_own_addr(net);
645 struct sk_buff *skb = NULL;
646 struct publication *p;
647
648 spin_lock_bh(&tn->nametbl_lock);
649
650 p = tipc_nametbl_remove_publ(net, type, lower, upper, self, key);
651 if (p) {
652 nt->local_publ_count--;
653 skb = tipc_named_withdraw(net, p);
654 list_del_init(&p->binding_sock);
655 kfree_rcu(p, rcu);
656 } else {
657 pr_err("Failed to remove local publication {%u,%u,%u}/%u\n",
658 type, lower, upper, key);
659 }
660 spin_unlock_bh(&tn->nametbl_lock);
661
662 if (skb) {
663 tipc_node_broadcast(net, skb);
664 return 1;
665 }
666 return 0;
667}
668
669/**
670 * tipc_nametbl_subscribe - add a subscription object to the name table
671 */
672bool tipc_nametbl_subscribe(struct tipc_subscription *sub)
673{
674 struct name_table *nt = tipc_name_table(sub->net);
675 struct tipc_net *tn = tipc_net(sub->net);
676 struct tipc_subscr *s = &sub->evt.s;
677 u32 type = tipc_sub_read(s, seq.type);
678 struct tipc_service *sc;
679 bool res = true;
680
681 spin_lock_bh(&tn->nametbl_lock);
682 sc = tipc_service_find(sub->net, type);
683 if (!sc)
684 sc = tipc_service_create(type, &nt->services[hash(type)]);
685 if (sc) {
686 spin_lock_bh(&sc->lock);
687 tipc_service_subscribe(sc, sub);
688 spin_unlock_bh(&sc->lock);
689 } else {
690 pr_warn("Failed to subscribe for {%u,%u,%u}\n", type,
691 tipc_sub_read(s, seq.lower),
692 tipc_sub_read(s, seq.upper));
693 res = false;
694 }
695 spin_unlock_bh(&tn->nametbl_lock);
696 return res;
697}
698
699/**
700 * tipc_nametbl_unsubscribe - remove a subscription object from name table
701 */
702void tipc_nametbl_unsubscribe(struct tipc_subscription *sub)
703{
704 struct tipc_net *tn = tipc_net(sub->net);
705 struct tipc_subscr *s = &sub->evt.s;
706 u32 type = tipc_sub_read(s, seq.type);
707 struct tipc_service *sc;
708
709 spin_lock_bh(&tn->nametbl_lock);
710 sc = tipc_service_find(sub->net, type);
711 if (!sc)
712 goto exit;
713
714 spin_lock_bh(&sc->lock);
715 list_del_init(&sub->service_list);
716 tipc_sub_put(sub);
717
718 /* Delete service item if no more publications and subscriptions */
719 if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) {
720 hlist_del_init_rcu(&sc->service_list);
721 kfree_rcu(sc, rcu);
722 }
723 spin_unlock_bh(&sc->lock);
724exit:
725 spin_unlock_bh(&tn->nametbl_lock);
726}
727
728int tipc_nametbl_init(struct net *net)
729{
730 struct tipc_net *tn = tipc_net(net);
731 struct name_table *nt;
732 int i;
733
734 nt = kzalloc(sizeof(*nt), GFP_ATOMIC);
735 if (!nt)
736 return -ENOMEM;
737
738 for (i = 0; i < TIPC_NAMETBL_SIZE; i++)
739 INIT_HLIST_HEAD(&nt->services[i]);
740
741 INIT_LIST_HEAD(&nt->node_scope);
742 INIT_LIST_HEAD(&nt->cluster_scope);
743 tn->nametbl = nt;
744 spin_lock_init(&tn->nametbl_lock);
745 return 0;
746}
747
748/**
749 * tipc_service_delete - purge all publications for a service and delete it
750 */
751static void tipc_service_delete(struct net *net, struct tipc_service *sc)
752{
753 struct service_range *sr, *tmpr;
754 struct publication *p, *tmp;
755
756 spin_lock_bh(&sc->lock);
757 rbtree_postorder_for_each_entry_safe(sr, tmpr, &sc->ranges, tree_node) {
758 list_for_each_entry_safe(p, tmp, &sr->all_publ, all_publ) {
759 tipc_service_remove_publ(net, sc, p->lower, p->upper,
760 p->node, p->key, &sr);
761 kfree_rcu(p, rcu);
762 }
763 rb_erase(&sr->tree_node, &sc->ranges);
764 kfree(sr);
765 }
766 hlist_del_init_rcu(&sc->service_list);
767 spin_unlock_bh(&sc->lock);
768 kfree_rcu(sc, rcu);
769}
770
771void tipc_nametbl_stop(struct net *net)
772{
773 struct name_table *nt = tipc_name_table(net);
774 struct tipc_net *tn = tipc_net(net);
775 struct hlist_head *service_head;
776 struct tipc_service *service;
777 u32 i;
778
779 /* Verify name table is empty and purge any lingering
780 * publications, then release the name table
781 */
782 spin_lock_bh(&tn->nametbl_lock);
783 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) {
784 if (hlist_empty(&nt->services[i]))
785 continue;
786 service_head = &nt->services[i];
787 hlist_for_each_entry_rcu(service, service_head, service_list) {
788 tipc_service_delete(net, service);
789 }
790 }
791 spin_unlock_bh(&tn->nametbl_lock);
792
793 synchronize_net();
794 kfree(nt);
795}
796
797static int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg,
798 struct tipc_service *service,
799 struct service_range *sr,
800 u32 *last_key)
801{
802 struct publication *p;
803 struct nlattr *attrs;
804 struct nlattr *b;
805 void *hdr;
806
807 if (*last_key) {
808 list_for_each_entry(p, &sr->all_publ, all_publ)
809 if (p->key == *last_key)
810 break;
811 if (p->key != *last_key)
812 return -EPIPE;
813 } else {
814 p = list_first_entry(&sr->all_publ,
815 struct publication,
816 all_publ);
817 }
818
819 list_for_each_entry_from(p, &sr->all_publ, all_publ) {
820 *last_key = p->key;
821
822 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq,
823 &tipc_genl_family, NLM_F_MULTI,
824 TIPC_NL_NAME_TABLE_GET);
825 if (!hdr)
826 return -EMSGSIZE;
827
828 attrs = nla_nest_start(msg->skb, TIPC_NLA_NAME_TABLE);
829 if (!attrs)
830 goto msg_full;
831
832 b = nla_nest_start(msg->skb, TIPC_NLA_NAME_TABLE_PUBL);
833 if (!b)
834 goto attr_msg_full;
835
836 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, service->type))
837 goto publ_msg_full;
838 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sr->lower))
839 goto publ_msg_full;
840 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sr->upper))
841 goto publ_msg_full;
842 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope))
843 goto publ_msg_full;
844 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->node))
845 goto publ_msg_full;
846 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->port))
847 goto publ_msg_full;
848 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key))
849 goto publ_msg_full;
850
851 nla_nest_end(msg->skb, b);
852 nla_nest_end(msg->skb, attrs);
853 genlmsg_end(msg->skb, hdr);
854 }
855 *last_key = 0;
856
857 return 0;
858
859publ_msg_full:
860 nla_nest_cancel(msg->skb, b);
861attr_msg_full:
862 nla_nest_cancel(msg->skb, attrs);
863msg_full:
864 genlmsg_cancel(msg->skb, hdr);
865
866 return -EMSGSIZE;
867}
868
869static int __tipc_nl_service_range_list(struct tipc_nl_msg *msg,
870 struct tipc_service *sc,
871 u32 *last_lower, u32 *last_key)
872{
873 struct service_range *sr;
874 struct rb_node *n;
875 int err;
876
877 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
878 sr = container_of(n, struct service_range, tree_node);
879 if (sr->lower < *last_lower)
880 continue;
881 err = __tipc_nl_add_nametable_publ(msg, sc, sr, last_key);
882 if (err) {
883 *last_lower = sr->lower;
884 return err;
885 }
886 }
887 *last_lower = 0;
888 return 0;
889}
890
891static int tipc_nl_service_list(struct net *net, struct tipc_nl_msg *msg,
892 u32 *last_type, u32 *last_lower, u32 *last_key)
893{
894 struct tipc_net *tn = tipc_net(net);
895 struct tipc_service *service = NULL;
896 struct hlist_head *head;
897 int err;
898 int i;
899
900 if (*last_type)
901 i = hash(*last_type);
902 else
903 i = 0;
904
905 for (; i < TIPC_NAMETBL_SIZE; i++) {
906 head = &tn->nametbl->services[i];
907
908 if (*last_type) {
909 service = tipc_service_find(net, *last_type);
910 if (!service)
911 return -EPIPE;
912 } else {
913 hlist_for_each_entry_rcu(service, head, service_list)
914 break;
915 if (!service)
916 continue;
917 }
918
919 hlist_for_each_entry_from_rcu(service, service_list) {
920 spin_lock_bh(&service->lock);
921 err = __tipc_nl_service_range_list(msg, service,
922 last_lower,
923 last_key);
924
925 if (err) {
926 *last_type = service->type;
927 spin_unlock_bh(&service->lock);
928 return err;
929 }
930 spin_unlock_bh(&service->lock);
931 }
932 *last_type = 0;
933 }
934 return 0;
935}
936
937int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb)
938{
939 struct net *net = sock_net(skb->sk);
940 u32 last_type = cb->args[0];
941 u32 last_lower = cb->args[1];
942 u32 last_key = cb->args[2];
943 int done = cb->args[3];
944 struct tipc_nl_msg msg;
945 int err;
946
947 if (done)
948 return 0;
949
950 msg.skb = skb;
951 msg.portid = NETLINK_CB(cb->skb).portid;
952 msg.seq = cb->nlh->nlmsg_seq;
953
954 rcu_read_lock();
955 err = tipc_nl_service_list(net, &msg, &last_type,
956 &last_lower, &last_key);
957 if (!err) {
958 done = 1;
959 } else if (err != -EMSGSIZE) {
960 /* We never set seq or call nl_dump_check_consistent() this
961 * means that setting prev_seq here will cause the consistence
962 * check to fail in the netlink callback handler. Resulting in
963 * the NLMSG_DONE message having the NLM_F_DUMP_INTR flag set if
964 * we got an error.
965 */
966 cb->prev_seq = 1;
967 }
968 rcu_read_unlock();
969
970 cb->args[0] = last_type;
971 cb->args[1] = last_lower;
972 cb->args[2] = last_key;
973 cb->args[3] = done;
974
975 return skb->len;
976}
977
978struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port)
979{
980 u64 value = (u64)node << 32 | port;
981 struct tipc_dest *dst;
982
983 list_for_each_entry(dst, l, list) {
984 if (dst->value != value)
985 continue;
986 return dst;
987 }
988 return NULL;
989}
990
991bool tipc_dest_push(struct list_head *l, u32 node, u32 port)
992{
993 u64 value = (u64)node << 32 | port;
994 struct tipc_dest *dst;
995
996 if (tipc_dest_find(l, node, port))
997 return false;
998
999 dst = kmalloc(sizeof(*dst), GFP_ATOMIC);
1000 if (unlikely(!dst))
1001 return false;
1002 dst->value = value;
1003 list_add(&dst->list, l);
1004 return true;
1005}
1006
1007bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port)
1008{
1009 struct tipc_dest *dst;
1010
1011 if (list_empty(l))
1012 return false;
1013 dst = list_first_entry(l, typeof(*dst), list);
1014 if (port)
1015 *port = dst->port;
1016 if (node)
1017 *node = dst->node;
1018 list_del(&dst->list);
1019 kfree(dst);
1020 return true;
1021}
1022
1023bool tipc_dest_del(struct list_head *l, u32 node, u32 port)
1024{
1025 struct tipc_dest *dst;
1026
1027 dst = tipc_dest_find(l, node, port);
1028 if (!dst)
1029 return false;
1030 list_del(&dst->list);
1031 kfree(dst);
1032 return true;
1033}
1034
1035void tipc_dest_list_purge(struct list_head *l)
1036{
1037 struct tipc_dest *dst, *tmp;
1038
1039 list_for_each_entry_safe(dst, tmp, l, list) {
1040 list_del(&dst->list);
1041 kfree(dst);
1042 }
1043}
1044
1045int tipc_dest_list_len(struct list_head *l)
1046{
1047 struct tipc_dest *dst;
1048 int i = 0;
1049
1050 list_for_each_entry(dst, l, list) {
1051 i++;
1052 }
1053 return i;
1054}