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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 * 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 */
62struct 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 */
81struct 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)
92RB_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 */
128static 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 */
178static 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
218static 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 */
229static 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 * @net: network namespace
253 * @ua: address representing the service to be bound
254 *
255 * Allocates a single range structure and sets it to all 0's.
256 */
257static struct tipc_service *tipc_service_create(struct net *net,
258 struct tipc_uaddr *ua)
259{
260 struct name_table *nt = tipc_name_table(net);
261 struct tipc_service *service;
262 struct hlist_head *hd;
263
264 service = kzalloc(sizeof(*service), GFP_ATOMIC);
265 if (!service) {
266 pr_warn("Service creation failed, no memory\n");
267 return NULL;
268 }
269
270 spin_lock_init(&service->lock);
271 service->type = ua->sr.type;
272 service->ranges = RB_ROOT;
273 INIT_HLIST_NODE(&service->service_list);
274 INIT_LIST_HEAD(&service->subscriptions);
275 hd = &nt->services[hash(ua->sr.type)];
276 hlist_add_head_rcu(&service->service_list, hd);
277 return service;
278}
279
280/* tipc_service_find_range - find service range matching publication parameters
281 */
282static struct service_range *tipc_service_find_range(struct tipc_service *sc,
283 struct tipc_uaddr *ua)
284{
285 struct service_range *sr;
286
287 service_range_foreach_match(sr, sc, ua->sr.lower, ua->sr.upper) {
288 /* Look for exact match */
289 if (sr->lower == ua->sr.lower && sr->upper == ua->sr.upper)
290 return sr;
291 }
292
293 return NULL;
294}
295
296static struct service_range *tipc_service_create_range(struct tipc_service *sc,
297 struct publication *p)
298{
299 struct rb_node **n, *parent = NULL;
300 struct service_range *sr;
301 u32 lower = p->sr.lower;
302 u32 upper = p->sr.upper;
303
304 n = &sc->ranges.rb_node;
305 while (*n) {
306 parent = *n;
307 sr = service_range_entry(parent);
308 if (lower == sr->lower && upper == sr->upper)
309 return sr;
310 if (sr->max < upper)
311 sr->max = upper;
312 if (lower <= sr->lower)
313 n = &parent->rb_left;
314 else
315 n = &parent->rb_right;
316 }
317 sr = kzalloc(sizeof(*sr), GFP_ATOMIC);
318 if (!sr)
319 return NULL;
320 sr->lower = lower;
321 sr->upper = upper;
322 sr->max = upper;
323 INIT_LIST_HEAD(&sr->local_publ);
324 INIT_LIST_HEAD(&sr->all_publ);
325 rb_link_node(&sr->tree_node, parent, n);
326 rb_insert_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks);
327 return sr;
328}
329
330static bool tipc_service_insert_publ(struct net *net,
331 struct tipc_service *sc,
332 struct publication *p)
333{
334 struct tipc_subscription *sub, *tmp;
335 struct service_range *sr;
336 struct publication *_p;
337 u32 node = p->sk.node;
338 bool first = false;
339 bool res = false;
340 u32 key = p->key;
341
342 spin_lock_bh(&sc->lock);
343 sr = tipc_service_create_range(sc, p);
344 if (!sr)
345 goto exit;
346
347 first = list_empty(&sr->all_publ);
348
349 /* Return if the publication already exists */
350 list_for_each_entry(_p, &sr->all_publ, all_publ) {
351 if (_p->key == key && (!_p->sk.node || _p->sk.node == node)) {
352 pr_debug("Failed to bind duplicate %u,%u,%u/%u:%u/%u\n",
353 p->sr.type, p->sr.lower, p->sr.upper,
354 node, p->sk.ref, key);
355 goto exit;
356 }
357 }
358
359 if (in_own_node(net, p->sk.node))
360 list_add(&p->local_publ, &sr->local_publ);
361 list_add(&p->all_publ, &sr->all_publ);
362 p->id = sc->publ_cnt++;
363
364 /* Any subscriptions waiting for notification? */
365 list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) {
366 tipc_sub_report_overlap(sub, p, TIPC_PUBLISHED, first);
367 }
368 res = true;
369exit:
370 if (!res)
371 pr_warn("Failed to bind to %u,%u,%u\n",
372 p->sr.type, p->sr.lower, p->sr.upper);
373 spin_unlock_bh(&sc->lock);
374 return res;
375}
376
377/**
378 * tipc_service_remove_publ - remove a publication from a service
379 * @r: service_range to remove publication from
380 * @sk: address publishing socket
381 * @key: target publication key
382 */
383static struct publication *tipc_service_remove_publ(struct service_range *r,
384 struct tipc_socket_addr *sk,
385 u32 key)
386{
387 struct publication *p;
388 u32 node = sk->node;
389
390 list_for_each_entry(p, &r->all_publ, all_publ) {
391 if (p->key != key || (node && node != p->sk.node))
392 continue;
393 list_del(&p->all_publ);
394 list_del(&p->local_publ);
395 return p;
396 }
397 return NULL;
398}
399
400/*
401 * Code reused: time_after32() for the same purpose
402 */
403#define publication_after(pa, pb) time_after32((pa)->id, (pb)->id)
404static int tipc_publ_sort(void *priv, const struct list_head *a,
405 const struct list_head *b)
406{
407 struct publication *pa, *pb;
408
409 pa = container_of(a, struct publication, list);
410 pb = container_of(b, struct publication, list);
411 return publication_after(pa, pb);
412}
413
414/**
415 * tipc_service_subscribe - attach a subscription, and optionally
416 * issue the prescribed number of events if there is any service
417 * range overlapping with the requested range
418 * @service: the tipc_service to attach the @sub to
419 * @sub: the subscription to attach
420 */
421static void tipc_service_subscribe(struct tipc_service *service,
422 struct tipc_subscription *sub)
423{
424 struct publication *p, *first, *tmp;
425 struct list_head publ_list;
426 struct service_range *sr;
427 u32 filter, lower, upper;
428
429 filter = sub->s.filter;
430 lower = sub->s.seq.lower;
431 upper = sub->s.seq.upper;
432
433 tipc_sub_get(sub);
434 list_add(&sub->service_list, &service->subscriptions);
435
436 if (filter & TIPC_SUB_NO_STATUS)
437 return;
438
439 INIT_LIST_HEAD(&publ_list);
440 service_range_foreach_match(sr, service, lower, upper) {
441 first = NULL;
442 list_for_each_entry(p, &sr->all_publ, all_publ) {
443 if (filter & TIPC_SUB_PORTS)
444 list_add_tail(&p->list, &publ_list);
445 else if (!first || publication_after(first, p))
446 /* Pick this range's *first* publication */
447 first = p;
448 }
449 if (first)
450 list_add_tail(&first->list, &publ_list);
451 }
452
453 /* Sort the publications before reporting */
454 list_sort(NULL, &publ_list, tipc_publ_sort);
455 list_for_each_entry_safe(p, tmp, &publ_list, list) {
456 tipc_sub_report_overlap(sub, p, TIPC_PUBLISHED, true);
457 list_del_init(&p->list);
458 }
459}
460
461static struct tipc_service *tipc_service_find(struct net *net,
462 struct tipc_uaddr *ua)
463{
464 struct name_table *nt = tipc_name_table(net);
465 struct hlist_head *service_head;
466 struct tipc_service *service;
467
468 service_head = &nt->services[hash(ua->sr.type)];
469 hlist_for_each_entry_rcu(service, service_head, service_list) {
470 if (service->type == ua->sr.type)
471 return service;
472 }
473 return NULL;
474};
475
476struct publication *tipc_nametbl_insert_publ(struct net *net,
477 struct tipc_uaddr *ua,
478 struct tipc_socket_addr *sk,
479 u32 key)
480{
481 struct tipc_service *sc;
482 struct publication *p;
483
484 p = tipc_publ_create(ua, sk, key);
485 if (!p)
486 return NULL;
487
488 sc = tipc_service_find(net, ua);
489 if (!sc)
490 sc = tipc_service_create(net, ua);
491 if (sc && tipc_service_insert_publ(net, sc, p))
492 return p;
493 kfree(p);
494 return NULL;
495}
496
497struct publication *tipc_nametbl_remove_publ(struct net *net,
498 struct tipc_uaddr *ua,
499 struct tipc_socket_addr *sk,
500 u32 key)
501{
502 struct tipc_subscription *sub, *tmp;
503 struct publication *p = NULL;
504 struct service_range *sr;
505 struct tipc_service *sc;
506 bool last;
507
508 sc = tipc_service_find(net, ua);
509 if (!sc)
510 goto exit;
511
512 spin_lock_bh(&sc->lock);
513 sr = tipc_service_find_range(sc, ua);
514 if (!sr)
515 goto unlock;
516 p = tipc_service_remove_publ(sr, sk, key);
517 if (!p)
518 goto unlock;
519
520 /* Notify any waiting subscriptions */
521 last = list_empty(&sr->all_publ);
522 list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) {
523 tipc_sub_report_overlap(sub, p, TIPC_WITHDRAWN, last);
524 }
525
526 /* Remove service range item if this was its last publication */
527 if (list_empty(&sr->all_publ)) {
528 rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks);
529 kfree(sr);
530 }
531
532 /* Delete service item if no more publications and subscriptions */
533 if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) {
534 hlist_del_init_rcu(&sc->service_list);
535 kfree_rcu(sc, rcu);
536 }
537unlock:
538 spin_unlock_bh(&sc->lock);
539exit:
540 if (!p) {
541 pr_err("Failed to remove unknown binding: %u,%u,%u/%u:%u/%u\n",
542 ua->sr.type, ua->sr.lower, ua->sr.upper,
543 sk->node, sk->ref, key);
544 }
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 *
557 * On exit:
558 *
559 * - If lookup is deferred to another node, leave 'sk->node' unchanged and
560 * return 'true'.
561 * - If lookup is successful, set the 'sk->node' and 'sk->ref' (== portid) which
562 * represent the bound socket and return 'true'.
563 * - If lookup fails, return 'false'
564 *
565 * Note that for legacy users (node configured with Z.C.N address format) the
566 * 'closest-first' lookup algorithm must be maintained, i.e., if sk.node is 0
567 * we must look in the local binding list first
568 */
569bool tipc_nametbl_lookup_anycast(struct net *net,
570 struct tipc_uaddr *ua,
571 struct tipc_socket_addr *sk)
572{
573 struct tipc_net *tn = tipc_net(net);
574 bool legacy = tn->legacy_addr_format;
575 u32 self = tipc_own_addr(net);
576 u32 inst = ua->sa.instance;
577 struct service_range *r;
578 struct tipc_service *sc;
579 struct publication *p;
580 struct list_head *l;
581 bool res = false;
582
583 if (!tipc_in_scope(legacy, sk->node, self))
584 return true;
585
586 rcu_read_lock();
587 sc = tipc_service_find(net, ua);
588 if (unlikely(!sc))
589 goto exit;
590
591 spin_lock_bh(&sc->lock);
592 service_range_foreach_match(r, sc, inst, inst) {
593 /* Select lookup algo: local, closest-first or round-robin */
594 if (sk->node == self) {
595 l = &r->local_publ;
596 if (list_empty(l))
597 continue;
598 p = list_first_entry(l, struct publication, local_publ);
599 list_move_tail(&p->local_publ, &r->local_publ);
600 } else if (legacy && !sk->node && !list_empty(&r->local_publ)) {
601 l = &r->local_publ;
602 p = list_first_entry(l, struct publication, local_publ);
603 list_move_tail(&p->local_publ, &r->local_publ);
604 } else {
605 l = &r->all_publ;
606 p = list_first_entry(l, struct publication, all_publ);
607 list_move_tail(&p->all_publ, &r->all_publ);
608 }
609 *sk = p->sk;
610 res = true;
611 /* Todo: as for legacy, pick the first matching range only, a
612 * "true" round-robin will be performed as needed.
613 */
614 break;
615 }
616 spin_unlock_bh(&sc->lock);
617
618exit:
619 rcu_read_unlock();
620 return res;
621}
622
623/* tipc_nametbl_lookup_group(): lookup destinaton(s) in a communication group
624 * Returns a list of one (== group anycast) or more (== group multicast)
625 * destination socket/node pairs matching the given address.
626 * The requester may or may not want to exclude himself from the list.
627 */
628bool tipc_nametbl_lookup_group(struct net *net, struct tipc_uaddr *ua,
629 struct list_head *dsts, int *dstcnt,
630 u32 exclude, bool mcast)
631{
632 u32 self = tipc_own_addr(net);
633 u32 inst = ua->sa.instance;
634 struct service_range *sr;
635 struct tipc_service *sc;
636 struct publication *p;
637
638 *dstcnt = 0;
639 rcu_read_lock();
640 sc = tipc_service_find(net, ua);
641 if (unlikely(!sc))
642 goto exit;
643
644 spin_lock_bh(&sc->lock);
645
646 /* Todo: a full search i.e. service_range_foreach_match() instead? */
647 sr = service_range_match_first(sc->ranges.rb_node, inst, inst);
648 if (!sr)
649 goto no_match;
650
651 list_for_each_entry(p, &sr->all_publ, all_publ) {
652 if (p->scope != ua->scope)
653 continue;
654 if (p->sk.ref == exclude && p->sk.node == self)
655 continue;
656 tipc_dest_push(dsts, p->sk.node, p->sk.ref);
657 (*dstcnt)++;
658 if (mcast)
659 continue;
660 list_move_tail(&p->all_publ, &sr->all_publ);
661 break;
662 }
663no_match:
664 spin_unlock_bh(&sc->lock);
665exit:
666 rcu_read_unlock();
667 return !list_empty(dsts);
668}
669
670/* tipc_nametbl_lookup_mcast_sockets(): look up node local destinaton sockets
671 * matching the given address
672 * Used on nodes which have received a multicast/broadcast message
673 * Returns a list of local sockets
674 */
675void tipc_nametbl_lookup_mcast_sockets(struct net *net, struct tipc_uaddr *ua,
676 struct list_head *dports)
677{
678 struct service_range *sr;
679 struct tipc_service *sc;
680 struct publication *p;
681 u8 scope = ua->scope;
682
683 rcu_read_lock();
684 sc = tipc_service_find(net, ua);
685 if (!sc)
686 goto exit;
687
688 spin_lock_bh(&sc->lock);
689 service_range_foreach_match(sr, sc, ua->sr.lower, ua->sr.upper) {
690 list_for_each_entry(p, &sr->local_publ, local_publ) {
691 if (scope == p->scope || scope == TIPC_ANY_SCOPE)
692 tipc_dest_push(dports, 0, p->sk.ref);
693 }
694 }
695 spin_unlock_bh(&sc->lock);
696exit:
697 rcu_read_unlock();
698}
699
700/* tipc_nametbl_lookup_mcast_nodes(): look up all destination nodes matching
701 * the given address. Used in sending node.
702 * Used on nodes which are sending out a multicast/broadcast message
703 * Returns a list of nodes, including own node if applicable
704 */
705void tipc_nametbl_lookup_mcast_nodes(struct net *net, struct tipc_uaddr *ua,
706 struct tipc_nlist *nodes)
707{
708 struct service_range *sr;
709 struct tipc_service *sc;
710 struct publication *p;
711
712 rcu_read_lock();
713 sc = tipc_service_find(net, ua);
714 if (!sc)
715 goto exit;
716
717 spin_lock_bh(&sc->lock);
718 service_range_foreach_match(sr, sc, ua->sr.lower, ua->sr.upper) {
719 list_for_each_entry(p, &sr->all_publ, all_publ) {
720 tipc_nlist_add(nodes, p->sk.node);
721 }
722 }
723 spin_unlock_bh(&sc->lock);
724exit:
725 rcu_read_unlock();
726}
727
728/* tipc_nametbl_build_group - build list of communication group members
729 */
730void tipc_nametbl_build_group(struct net *net, struct tipc_group *grp,
731 struct tipc_uaddr *ua)
732{
733 struct service_range *sr;
734 struct tipc_service *sc;
735 struct publication *p;
736 struct rb_node *n;
737
738 rcu_read_lock();
739 sc = tipc_service_find(net, ua);
740 if (!sc)
741 goto exit;
742
743 spin_lock_bh(&sc->lock);
744 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
745 sr = container_of(n, struct service_range, tree_node);
746 list_for_each_entry(p, &sr->all_publ, all_publ) {
747 if (p->scope != ua->scope)
748 continue;
749 tipc_group_add_member(grp, p->sk.node, p->sk.ref,
750 p->sr.lower);
751 }
752 }
753 spin_unlock_bh(&sc->lock);
754exit:
755 rcu_read_unlock();
756}
757
758/* tipc_nametbl_publish - add service binding to name table
759 */
760struct publication *tipc_nametbl_publish(struct net *net, struct tipc_uaddr *ua,
761 struct tipc_socket_addr *sk, u32 key)
762{
763 struct name_table *nt = tipc_name_table(net);
764 struct tipc_net *tn = tipc_net(net);
765 struct publication *p = NULL;
766 struct sk_buff *skb = NULL;
767 u32 rc_dests;
768
769 spin_lock_bh(&tn->nametbl_lock);
770
771 if (nt->local_publ_count >= TIPC_MAX_PUBL) {
772 pr_warn("Bind failed, max limit %u reached\n", TIPC_MAX_PUBL);
773 goto exit;
774 }
775
776 p = tipc_nametbl_insert_publ(net, ua, sk, key);
777 if (p) {
778 nt->local_publ_count++;
779 skb = tipc_named_publish(net, p);
780 }
781 rc_dests = nt->rc_dests;
782exit:
783 spin_unlock_bh(&tn->nametbl_lock);
784
785 if (skb)
786 tipc_node_broadcast(net, skb, rc_dests);
787 return p;
788
789}
790
791/**
792 * tipc_nametbl_withdraw - withdraw a service binding
793 * @net: network namespace
794 * @ua: service address/range being unbound
795 * @sk: address of the socket being unbound from
796 * @key: target publication key
797 */
798void tipc_nametbl_withdraw(struct net *net, struct tipc_uaddr *ua,
799 struct tipc_socket_addr *sk, u32 key)
800{
801 struct name_table *nt = tipc_name_table(net);
802 struct tipc_net *tn = tipc_net(net);
803 struct sk_buff *skb = NULL;
804 struct publication *p;
805 u32 rc_dests;
806
807 spin_lock_bh(&tn->nametbl_lock);
808
809 p = tipc_nametbl_remove_publ(net, ua, sk, key);
810 if (p) {
811 nt->local_publ_count--;
812 skb = tipc_named_withdraw(net, p);
813 list_del_init(&p->binding_sock);
814 kfree_rcu(p, rcu);
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 */
827bool tipc_nametbl_subscribe(struct tipc_subscription *sub)
828{
829 struct tipc_net *tn = tipc_net(sub->net);
830 u32 type = sub->s.seq.type;
831 struct tipc_service *sc;
832 struct tipc_uaddr ua;
833 bool res = true;
834
835 tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_NODE_SCOPE, type,
836 sub->s.seq.lower, sub->s.seq.upper);
837 spin_lock_bh(&tn->nametbl_lock);
838 sc = tipc_service_find(sub->net, &ua);
839 if (!sc)
840 sc = tipc_service_create(sub->net, &ua);
841 if (sc) {
842 spin_lock_bh(&sc->lock);
843 tipc_service_subscribe(sc, sub);
844 spin_unlock_bh(&sc->lock);
845 } else {
846 pr_warn("Failed to subscribe for {%u,%u,%u}\n",
847 type, sub->s.seq.lower, sub->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 */
858void tipc_nametbl_unsubscribe(struct tipc_subscription *sub)
859{
860 struct tipc_net *tn = tipc_net(sub->net);
861 struct tipc_service *sc;
862 struct tipc_uaddr ua;
863
864 tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_NODE_SCOPE,
865 sub->s.seq.type, sub->s.seq.lower, sub->s.seq.upper);
866 spin_lock_bh(&tn->nametbl_lock);
867 sc = tipc_service_find(sub->net, &ua);
868 if (!sc)
869 goto exit;
870
871 spin_lock_bh(&sc->lock);
872 list_del_init(&sub->service_list);
873 tipc_sub_put(sub);
874
875 /* Delete service item if no more publications and subscriptions */
876 if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) {
877 hlist_del_init_rcu(&sc->service_list);
878 kfree_rcu(sc, rcu);
879 }
880 spin_unlock_bh(&sc->lock);
881exit:
882 spin_unlock_bh(&tn->nametbl_lock);
883}
884
885int tipc_nametbl_init(struct net *net)
886{
887 struct tipc_net *tn = tipc_net(net);
888 struct name_table *nt;
889 int i;
890
891 nt = kzalloc(sizeof(*nt), GFP_KERNEL);
892 if (!nt)
893 return -ENOMEM;
894
895 for (i = 0; i < TIPC_NAMETBL_SIZE; i++)
896 INIT_HLIST_HEAD(&nt->services[i]);
897
898 INIT_LIST_HEAD(&nt->node_scope);
899 INIT_LIST_HEAD(&nt->cluster_scope);
900 rwlock_init(&nt->cluster_scope_lock);
901 tn->nametbl = nt;
902 spin_lock_init(&tn->nametbl_lock);
903 return 0;
904}
905
906/**
907 * tipc_service_delete - purge all publications for a service and delete it
908 * @net: the associated network namespace
909 * @sc: tipc_service to delete
910 */
911static void tipc_service_delete(struct net *net, struct tipc_service *sc)
912{
913 struct service_range *sr, *tmpr;
914 struct publication *p, *tmp;
915
916 spin_lock_bh(&sc->lock);
917 rbtree_postorder_for_each_entry_safe(sr, tmpr, &sc->ranges, tree_node) {
918 list_for_each_entry_safe(p, tmp, &sr->all_publ, all_publ) {
919 tipc_service_remove_publ(sr, &p->sk, p->key);
920 kfree_rcu(p, rcu);
921 }
922 rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks);
923 kfree(sr);
924 }
925 hlist_del_init_rcu(&sc->service_list);
926 spin_unlock_bh(&sc->lock);
927 kfree_rcu(sc, rcu);
928}
929
930void tipc_nametbl_stop(struct net *net)
931{
932 struct name_table *nt = tipc_name_table(net);
933 struct tipc_net *tn = tipc_net(net);
934 struct hlist_head *service_head;
935 struct tipc_service *service;
936 u32 i;
937
938 /* Verify name table is empty and purge any lingering
939 * publications, then release the name table
940 */
941 spin_lock_bh(&tn->nametbl_lock);
942 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) {
943 if (hlist_empty(&nt->services[i]))
944 continue;
945 service_head = &nt->services[i];
946 hlist_for_each_entry_rcu(service, service_head, service_list) {
947 tipc_service_delete(net, service);
948 }
949 }
950 spin_unlock_bh(&tn->nametbl_lock);
951
952 synchronize_net();
953 kfree(nt);
954}
955
956static int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg,
957 struct tipc_service *service,
958 struct service_range *sr,
959 u32 *last_key)
960{
961 struct publication *p;
962 struct nlattr *attrs;
963 struct nlattr *b;
964 void *hdr;
965
966 if (*last_key) {
967 list_for_each_entry(p, &sr->all_publ, all_publ)
968 if (p->key == *last_key)
969 break;
970 if (list_entry_is_head(p, &sr->all_publ, all_publ))
971 return -EPIPE;
972 } else {
973 p = list_first_entry(&sr->all_publ,
974 struct publication,
975 all_publ);
976 }
977
978 list_for_each_entry_from(p, &sr->all_publ, all_publ) {
979 *last_key = p->key;
980
981 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq,
982 &tipc_genl_family, NLM_F_MULTI,
983 TIPC_NL_NAME_TABLE_GET);
984 if (!hdr)
985 return -EMSGSIZE;
986
987 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE);
988 if (!attrs)
989 goto msg_full;
990
991 b = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE_PUBL);
992 if (!b)
993 goto attr_msg_full;
994
995 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, service->type))
996 goto publ_msg_full;
997 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sr->lower))
998 goto publ_msg_full;
999 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sr->upper))
1000 goto publ_msg_full;
1001 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope))
1002 goto publ_msg_full;
1003 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->sk.node))
1004 goto publ_msg_full;
1005 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->sk.ref))
1006 goto publ_msg_full;
1007 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key))
1008 goto publ_msg_full;
1009
1010 nla_nest_end(msg->skb, b);
1011 nla_nest_end(msg->skb, attrs);
1012 genlmsg_end(msg->skb, hdr);
1013 }
1014 *last_key = 0;
1015
1016 return 0;
1017
1018publ_msg_full:
1019 nla_nest_cancel(msg->skb, b);
1020attr_msg_full:
1021 nla_nest_cancel(msg->skb, attrs);
1022msg_full:
1023 genlmsg_cancel(msg->skb, hdr);
1024
1025 return -EMSGSIZE;
1026}
1027
1028static int __tipc_nl_service_range_list(struct tipc_nl_msg *msg,
1029 struct tipc_service *sc,
1030 u32 *last_lower, u32 *last_key)
1031{
1032 struct service_range *sr;
1033 struct rb_node *n;
1034 int err;
1035
1036 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
1037 sr = container_of(n, struct service_range, tree_node);
1038 if (sr->lower < *last_lower)
1039 continue;
1040 err = __tipc_nl_add_nametable_publ(msg, sc, sr, last_key);
1041 if (err) {
1042 *last_lower = sr->lower;
1043 return err;
1044 }
1045 }
1046 *last_lower = 0;
1047 return 0;
1048}
1049
1050static int tipc_nl_service_list(struct net *net, struct tipc_nl_msg *msg,
1051 u32 *last_type, u32 *last_lower, u32 *last_key)
1052{
1053 struct tipc_net *tn = tipc_net(net);
1054 struct tipc_service *service = NULL;
1055 struct hlist_head *head;
1056 struct tipc_uaddr ua;
1057 int err;
1058 int i;
1059
1060 if (*last_type)
1061 i = hash(*last_type);
1062 else
1063 i = 0;
1064
1065 for (; i < TIPC_NAMETBL_SIZE; i++) {
1066 head = &tn->nametbl->services[i];
1067
1068 if (*last_type ||
1069 (!i && *last_key && (*last_lower == *last_key))) {
1070 tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_NODE_SCOPE,
1071 *last_type, *last_lower, *last_lower);
1072 service = tipc_service_find(net, &ua);
1073 if (!service)
1074 return -EPIPE;
1075 } else {
1076 hlist_for_each_entry_rcu(service, head, service_list)
1077 break;
1078 if (!service)
1079 continue;
1080 }
1081
1082 hlist_for_each_entry_from_rcu(service, service_list) {
1083 spin_lock_bh(&service->lock);
1084 err = __tipc_nl_service_range_list(msg, service,
1085 last_lower,
1086 last_key);
1087
1088 if (err) {
1089 *last_type = service->type;
1090 spin_unlock_bh(&service->lock);
1091 return err;
1092 }
1093 spin_unlock_bh(&service->lock);
1094 }
1095 *last_type = 0;
1096 }
1097 return 0;
1098}
1099
1100int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb)
1101{
1102 struct net *net = sock_net(skb->sk);
1103 u32 last_type = cb->args[0];
1104 u32 last_lower = cb->args[1];
1105 u32 last_key = cb->args[2];
1106 int done = cb->args[3];
1107 struct tipc_nl_msg msg;
1108 int err;
1109
1110 if (done)
1111 return 0;
1112
1113 msg.skb = skb;
1114 msg.portid = NETLINK_CB(cb->skb).portid;
1115 msg.seq = cb->nlh->nlmsg_seq;
1116
1117 rcu_read_lock();
1118 err = tipc_nl_service_list(net, &msg, &last_type,
1119 &last_lower, &last_key);
1120 if (!err) {
1121 done = 1;
1122 } else if (err != -EMSGSIZE) {
1123 /* We never set seq or call nl_dump_check_consistent() this
1124 * means that setting prev_seq here will cause the consistence
1125 * check to fail in the netlink callback handler. Resulting in
1126 * the NLMSG_DONE message having the NLM_F_DUMP_INTR flag set if
1127 * we got an error.
1128 */
1129 cb->prev_seq = 1;
1130 }
1131 rcu_read_unlock();
1132
1133 cb->args[0] = last_type;
1134 cb->args[1] = last_lower;
1135 cb->args[2] = last_key;
1136 cb->args[3] = done;
1137
1138 return skb->len;
1139}
1140
1141struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port)
1142{
1143 struct tipc_dest *dst;
1144
1145 list_for_each_entry(dst, l, list) {
1146 if (dst->node == node && dst->port == port)
1147 return dst;
1148 }
1149 return NULL;
1150}
1151
1152bool tipc_dest_push(struct list_head *l, u32 node, u32 port)
1153{
1154 struct tipc_dest *dst;
1155
1156 if (tipc_dest_find(l, node, port))
1157 return false;
1158
1159 dst = kmalloc(sizeof(*dst), GFP_ATOMIC);
1160 if (unlikely(!dst))
1161 return false;
1162 dst->node = node;
1163 dst->port = port;
1164 list_add(&dst->list, l);
1165 return true;
1166}
1167
1168bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port)
1169{
1170 struct tipc_dest *dst;
1171
1172 if (list_empty(l))
1173 return false;
1174 dst = list_first_entry(l, typeof(*dst), list);
1175 if (port)
1176 *port = dst->port;
1177 if (node)
1178 *node = dst->node;
1179 list_del(&dst->list);
1180 kfree(dst);
1181 return true;
1182}
1183
1184bool tipc_dest_del(struct list_head *l, u32 node, u32 port)
1185{
1186 struct tipc_dest *dst;
1187
1188 dst = tipc_dest_find(l, node, port);
1189 if (!dst)
1190 return false;
1191 list_del(&dst->list);
1192 kfree(dst);
1193 return true;
1194}
1195
1196void tipc_dest_list_purge(struct list_head *l)
1197{
1198 struct tipc_dest *dst, *tmp;
1199
1200 list_for_each_entry_safe(dst, tmp, l, list) {
1201 list_del(&dst->list);
1202 kfree(dst);
1203 }
1204}
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}