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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_first_range - find first service range in tree matching instance
140 *
141 * Very time-critical, so binary search through range rb tree
142 */
143static struct service_range *tipc_service_first_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
161/* tipc_service_find_range - find service range matching publication parameters
162 */
163static struct service_range *tipc_service_find_range(struct tipc_service *sc,
164 u32 lower, u32 upper)
165{
166 struct rb_node *n = sc->ranges.rb_node;
167 struct service_range *sr;
168
169 sr = tipc_service_first_range(sc, lower);
170 if (!sr)
171 return NULL;
172
173 /* Look for exact match */
174 for (n = &sr->tree_node; n; n = rb_next(n)) {
175 sr = container_of(n, struct service_range, tree_node);
176 if (sr->upper == upper)
177 break;
178 }
179 if (!n || sr->lower != lower || sr->upper != upper)
180 return NULL;
181
182 return sr;
183}
184
185static struct service_range *tipc_service_create_range(struct tipc_service *sc,
186 u32 lower, u32 upper)
187{
188 struct rb_node **n, *parent = NULL;
189 struct service_range *sr, *tmp;
190
191 n = &sc->ranges.rb_node;
192 while (*n) {
193 tmp = container_of(*n, struct service_range, tree_node);
194 parent = *n;
195 tmp = container_of(parent, struct service_range, tree_node);
196 if (lower < tmp->lower)
197 n = &(*n)->rb_left;
198 else if (lower > tmp->lower)
199 n = &(*n)->rb_right;
200 else if (upper < tmp->upper)
201 n = &(*n)->rb_left;
202 else if (upper > tmp->upper)
203 n = &(*n)->rb_right;
204 else
205 return tmp;
206 }
207 sr = kzalloc(sizeof(*sr), GFP_ATOMIC);
208 if (!sr)
209 return NULL;
210 sr->lower = lower;
211 sr->upper = upper;
212 INIT_LIST_HEAD(&sr->local_publ);
213 INIT_LIST_HEAD(&sr->all_publ);
214 rb_link_node(&sr->tree_node, parent, n);
215 rb_insert_color(&sr->tree_node, &sc->ranges);
216 return sr;
217}
218
219static struct publication *tipc_service_insert_publ(struct net *net,
220 struct tipc_service *sc,
221 u32 type, u32 lower,
222 u32 upper, u32 scope,
223 u32 node, u32 port,
224 u32 key)
225{
226 struct tipc_subscription *sub, *tmp;
227 struct service_range *sr;
228 struct publication *p;
229 bool first = false;
230
231 sr = tipc_service_create_range(sc, lower, upper);
232 if (!sr)
233 goto err;
234
235 first = list_empty(&sr->all_publ);
236
237 /* Return if the publication already exists */
238 list_for_each_entry(p, &sr->all_publ, all_publ) {
239 if (p->key == key && (!p->node || p->node == node))
240 return NULL;
241 }
242
243 /* Create and insert publication */
244 p = tipc_publ_create(type, lower, upper, scope, node, port, key);
245 if (!p)
246 goto err;
247 if (in_own_node(net, node))
248 list_add(&p->local_publ, &sr->local_publ);
249 list_add(&p->all_publ, &sr->all_publ);
250
251 /* Any subscriptions waiting for notification? */
252 list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) {
253 tipc_sub_report_overlap(sub, p->lower, p->upper, TIPC_PUBLISHED,
254 p->port, p->node, p->scope, first);
255 }
256 return p;
257err:
258 pr_warn("Failed to bind to %u,%u,%u, no memory\n", type, lower, upper);
259 return NULL;
260}
261
262/**
263 * tipc_service_remove_publ - remove a publication from a service
264 */
265static struct publication *tipc_service_remove_publ(struct service_range *sr,
266 u32 node, u32 key)
267{
268 struct publication *p;
269
270 list_for_each_entry(p, &sr->all_publ, all_publ) {
271 if (p->key != key || (node && node != p->node))
272 continue;
273 list_del(&p->all_publ);
274 list_del(&p->local_publ);
275 return p;
276 }
277 return NULL;
278}
279
280/**
281 * tipc_service_subscribe - attach a subscription, and optionally
282 * issue the prescribed number of events if there is any service
283 * range overlapping with the requested range
284 */
285static void tipc_service_subscribe(struct tipc_service *service,
286 struct tipc_subscription *sub)
287{
288 struct tipc_subscr *sb = &sub->evt.s;
289 struct service_range *sr;
290 struct tipc_name_seq ns;
291 struct publication *p;
292 struct rb_node *n;
293 bool first;
294
295 ns.type = tipc_sub_read(sb, seq.type);
296 ns.lower = tipc_sub_read(sb, seq.lower);
297 ns.upper = tipc_sub_read(sb, seq.upper);
298
299 tipc_sub_get(sub);
300 list_add(&sub->service_list, &service->subscriptions);
301
302 if (tipc_sub_read(sb, filter) & TIPC_SUB_NO_STATUS)
303 return;
304
305 for (n = rb_first(&service->ranges); n; n = rb_next(n)) {
306 sr = container_of(n, struct service_range, tree_node);
307 if (sr->lower > ns.upper)
308 break;
309 if (!tipc_sub_check_overlap(&ns, sr->lower, sr->upper))
310 continue;
311 first = true;
312
313 list_for_each_entry(p, &sr->all_publ, all_publ) {
314 tipc_sub_report_overlap(sub, sr->lower, sr->upper,
315 TIPC_PUBLISHED, p->port,
316 p->node, p->scope, first);
317 first = false;
318 }
319 }
320}
321
322static struct tipc_service *tipc_service_find(struct net *net, u32 type)
323{
324 struct name_table *nt = tipc_name_table(net);
325 struct hlist_head *service_head;
326 struct tipc_service *service;
327
328 service_head = &nt->services[hash(type)];
329 hlist_for_each_entry_rcu(service, service_head, service_list) {
330 if (service->type == type)
331 return service;
332 }
333 return NULL;
334};
335
336struct publication *tipc_nametbl_insert_publ(struct net *net, u32 type,
337 u32 lower, u32 upper,
338 u32 scope, u32 node,
339 u32 port, u32 key)
340{
341 struct name_table *nt = tipc_name_table(net);
342 struct tipc_service *sc;
343 struct publication *p;
344
345 if (scope > TIPC_NODE_SCOPE || lower > upper) {
346 pr_debug("Failed to bind illegal {%u,%u,%u} with scope %u\n",
347 type, lower, upper, scope);
348 return NULL;
349 }
350 sc = tipc_service_find(net, type);
351 if (!sc)
352 sc = tipc_service_create(type, &nt->services[hash(type)]);
353 if (!sc)
354 return NULL;
355
356 spin_lock_bh(&sc->lock);
357 p = tipc_service_insert_publ(net, sc, type, lower, upper,
358 scope, node, port, key);
359 spin_unlock_bh(&sc->lock);
360 return p;
361}
362
363struct publication *tipc_nametbl_remove_publ(struct net *net, u32 type,
364 u32 lower, u32 upper,
365 u32 node, u32 key)
366{
367 struct tipc_service *sc = tipc_service_find(net, type);
368 struct tipc_subscription *sub, *tmp;
369 struct service_range *sr = NULL;
370 struct publication *p = NULL;
371 bool last;
372
373 if (!sc)
374 return NULL;
375
376 spin_lock_bh(&sc->lock);
377 sr = tipc_service_find_range(sc, lower, upper);
378 if (!sr)
379 goto exit;
380 p = tipc_service_remove_publ(sr, node, key);
381 if (!p)
382 goto exit;
383
384 /* Notify any waiting subscriptions */
385 last = list_empty(&sr->all_publ);
386 list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) {
387 tipc_sub_report_overlap(sub, lower, upper, TIPC_WITHDRAWN,
388 p->port, node, p->scope, last);
389 }
390
391 /* Remove service range item if this was its last publication */
392 if (list_empty(&sr->all_publ)) {
393 rb_erase(&sr->tree_node, &sc->ranges);
394 kfree(sr);
395 }
396
397 /* Delete service item if this no more publications and subscriptions */
398 if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) {
399 hlist_del_init_rcu(&sc->service_list);
400 kfree_rcu(sc, rcu);
401 }
402exit:
403 spin_unlock_bh(&sc->lock);
404 return p;
405}
406
407/**
408 * tipc_nametbl_translate - perform service instance to socket translation
409 *
410 * On entry, 'dnode' is the search domain used during translation.
411 *
412 * On exit:
413 * - if translation is deferred to another node, leave 'dnode' unchanged and
414 * return 0
415 * - if translation is attempted and succeeds, set 'dnode' to the publishing
416 * node and return the published (non-zero) port number
417 * - if translation is attempted and fails, set 'dnode' to 0 and return 0
418 *
419 * Note that for legacy users (node configured with Z.C.N address format) the
420 * 'closest-first' lookup algorithm must be maintained, i.e., if dnode is 0
421 * we must look in the local binding list first
422 */
423u32 tipc_nametbl_translate(struct net *net, u32 type, u32 instance, u32 *dnode)
424{
425 struct tipc_net *tn = tipc_net(net);
426 bool legacy = tn->legacy_addr_format;
427 u32 self = tipc_own_addr(net);
428 struct service_range *sr;
429 struct tipc_service *sc;
430 struct list_head *list;
431 struct publication *p;
432 u32 port = 0;
433 u32 node = 0;
434
435 if (!tipc_in_scope(legacy, *dnode, self))
436 return 0;
437
438 rcu_read_lock();
439 sc = tipc_service_find(net, type);
440 if (unlikely(!sc))
441 goto not_found;
442
443 spin_lock_bh(&sc->lock);
444 sr = tipc_service_first_range(sc, instance);
445 if (unlikely(!sr))
446 goto no_match;
447
448 /* Select lookup algorithm: local, closest-first or round-robin */
449 if (*dnode == self) {
450 list = &sr->local_publ;
451 if (list_empty(list))
452 goto no_match;
453 p = list_first_entry(list, struct publication, local_publ);
454 list_move_tail(&p->local_publ, &sr->local_publ);
455 } else if (legacy && !*dnode && !list_empty(&sr->local_publ)) {
456 list = &sr->local_publ;
457 p = list_first_entry(list, struct publication, local_publ);
458 list_move_tail(&p->local_publ, &sr->local_publ);
459 } else {
460 list = &sr->all_publ;
461 p = list_first_entry(list, struct publication, all_publ);
462 list_move_tail(&p->all_publ, &sr->all_publ);
463 }
464 port = p->port;
465 node = p->node;
466no_match:
467 spin_unlock_bh(&sc->lock);
468not_found:
469 rcu_read_unlock();
470 *dnode = node;
471 return port;
472}
473
474bool tipc_nametbl_lookup(struct net *net, u32 type, u32 instance, u32 scope,
475 struct list_head *dsts, int *dstcnt, u32 exclude,
476 bool all)
477{
478 u32 self = tipc_own_addr(net);
479 struct service_range *sr;
480 struct tipc_service *sc;
481 struct publication *p;
482
483 *dstcnt = 0;
484 rcu_read_lock();
485 sc = tipc_service_find(net, type);
486 if (unlikely(!sc))
487 goto exit;
488
489 spin_lock_bh(&sc->lock);
490
491 sr = tipc_service_first_range(sc, instance);
492 if (!sr)
493 goto no_match;
494
495 list_for_each_entry(p, &sr->all_publ, all_publ) {
496 if (p->scope != scope)
497 continue;
498 if (p->port == exclude && p->node == self)
499 continue;
500 tipc_dest_push(dsts, p->node, p->port);
501 (*dstcnt)++;
502 if (all)
503 continue;
504 list_move_tail(&p->all_publ, &sr->all_publ);
505 break;
506 }
507no_match:
508 spin_unlock_bh(&sc->lock);
509exit:
510 rcu_read_unlock();
511 return !list_empty(dsts);
512}
513
514void tipc_nametbl_mc_lookup(struct net *net, u32 type, u32 lower, u32 upper,
515 u32 scope, bool exact, struct list_head *dports)
516{
517 struct service_range *sr;
518 struct tipc_service *sc;
519 struct publication *p;
520 struct rb_node *n;
521
522 rcu_read_lock();
523 sc = tipc_service_find(net, type);
524 if (!sc)
525 goto exit;
526
527 spin_lock_bh(&sc->lock);
528
529 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
530 sr = container_of(n, struct service_range, tree_node);
531 if (sr->upper < lower)
532 continue;
533 if (sr->lower > upper)
534 break;
535 list_for_each_entry(p, &sr->local_publ, local_publ) {
536 if (p->scope == scope || (!exact && p->scope < scope))
537 tipc_dest_push(dports, 0, p->port);
538 }
539 }
540 spin_unlock_bh(&sc->lock);
541exit:
542 rcu_read_unlock();
543}
544
545/* tipc_nametbl_lookup_dst_nodes - find broadcast destination nodes
546 * - Creates list of nodes that overlap the given multicast address
547 * - Determines if any node local destinations overlap
548 */
549void tipc_nametbl_lookup_dst_nodes(struct net *net, u32 type, u32 lower,
550 u32 upper, struct tipc_nlist *nodes)
551{
552 struct service_range *sr;
553 struct tipc_service *sc;
554 struct publication *p;
555 struct rb_node *n;
556
557 rcu_read_lock();
558 sc = tipc_service_find(net, type);
559 if (!sc)
560 goto exit;
561
562 spin_lock_bh(&sc->lock);
563
564 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
565 sr = container_of(n, struct service_range, tree_node);
566 if (sr->upper < lower)
567 continue;
568 if (sr->lower > upper)
569 break;
570 list_for_each_entry(p, &sr->all_publ, all_publ) {
571 tipc_nlist_add(nodes, p->node);
572 }
573 }
574 spin_unlock_bh(&sc->lock);
575exit:
576 rcu_read_unlock();
577}
578
579/* tipc_nametbl_build_group - build list of communication group members
580 */
581void tipc_nametbl_build_group(struct net *net, struct tipc_group *grp,
582 u32 type, u32 scope)
583{
584 struct service_range *sr;
585 struct tipc_service *sc;
586 struct publication *p;
587 struct rb_node *n;
588
589 rcu_read_lock();
590 sc = tipc_service_find(net, type);
591 if (!sc)
592 goto exit;
593
594 spin_lock_bh(&sc->lock);
595 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
596 sr = container_of(n, struct service_range, tree_node);
597 list_for_each_entry(p, &sr->all_publ, all_publ) {
598 if (p->scope != scope)
599 continue;
600 tipc_group_add_member(grp, p->node, p->port, p->lower);
601 }
602 }
603 spin_unlock_bh(&sc->lock);
604exit:
605 rcu_read_unlock();
606}
607
608/* tipc_nametbl_publish - add service binding to name table
609 */
610struct publication *tipc_nametbl_publish(struct net *net, u32 type, u32 lower,
611 u32 upper, u32 scope, u32 port,
612 u32 key)
613{
614 struct name_table *nt = tipc_name_table(net);
615 struct tipc_net *tn = tipc_net(net);
616 struct publication *p = NULL;
617 struct sk_buff *skb = NULL;
618
619 spin_lock_bh(&tn->nametbl_lock);
620
621 if (nt->local_publ_count >= TIPC_MAX_PUBL) {
622 pr_warn("Bind failed, max limit %u reached\n", TIPC_MAX_PUBL);
623 goto exit;
624 }
625
626 p = tipc_nametbl_insert_publ(net, type, lower, upper, scope,
627 tipc_own_addr(net), port, key);
628 if (p) {
629 nt->local_publ_count++;
630 skb = tipc_named_publish(net, p);
631 }
632exit:
633 spin_unlock_bh(&tn->nametbl_lock);
634
635 if (skb)
636 tipc_node_broadcast(net, skb);
637 return p;
638}
639
640/**
641 * tipc_nametbl_withdraw - withdraw a service binding
642 */
643int tipc_nametbl_withdraw(struct net *net, u32 type, u32 lower,
644 u32 upper, u32 key)
645{
646 struct name_table *nt = tipc_name_table(net);
647 struct tipc_net *tn = tipc_net(net);
648 u32 self = tipc_own_addr(net);
649 struct sk_buff *skb = NULL;
650 struct publication *p;
651
652 spin_lock_bh(&tn->nametbl_lock);
653
654 p = tipc_nametbl_remove_publ(net, type, lower, upper, self, key);
655 if (p) {
656 nt->local_publ_count--;
657 skb = tipc_named_withdraw(net, p);
658 list_del_init(&p->binding_sock);
659 kfree_rcu(p, rcu);
660 } else {
661 pr_err("Failed to remove local publication {%u,%u,%u}/%u\n",
662 type, lower, upper, key);
663 }
664 spin_unlock_bh(&tn->nametbl_lock);
665
666 if (skb) {
667 tipc_node_broadcast(net, skb);
668 return 1;
669 }
670 return 0;
671}
672
673/**
674 * tipc_nametbl_subscribe - add a subscription object to the name table
675 */
676bool tipc_nametbl_subscribe(struct tipc_subscription *sub)
677{
678 struct name_table *nt = tipc_name_table(sub->net);
679 struct tipc_net *tn = tipc_net(sub->net);
680 struct tipc_subscr *s = &sub->evt.s;
681 u32 type = tipc_sub_read(s, seq.type);
682 struct tipc_service *sc;
683 bool res = true;
684
685 spin_lock_bh(&tn->nametbl_lock);
686 sc = tipc_service_find(sub->net, type);
687 if (!sc)
688 sc = tipc_service_create(type, &nt->services[hash(type)]);
689 if (sc) {
690 spin_lock_bh(&sc->lock);
691 tipc_service_subscribe(sc, sub);
692 spin_unlock_bh(&sc->lock);
693 } else {
694 pr_warn("Failed to subscribe for {%u,%u,%u}\n", type,
695 tipc_sub_read(s, seq.lower),
696 tipc_sub_read(s, seq.upper));
697 res = false;
698 }
699 spin_unlock_bh(&tn->nametbl_lock);
700 return res;
701}
702
703/**
704 * tipc_nametbl_unsubscribe - remove a subscription object from name table
705 */
706void tipc_nametbl_unsubscribe(struct tipc_subscription *sub)
707{
708 struct tipc_net *tn = tipc_net(sub->net);
709 struct tipc_subscr *s = &sub->evt.s;
710 u32 type = tipc_sub_read(s, seq.type);
711 struct tipc_service *sc;
712
713 spin_lock_bh(&tn->nametbl_lock);
714 sc = tipc_service_find(sub->net, type);
715 if (!sc)
716 goto exit;
717
718 spin_lock_bh(&sc->lock);
719 list_del_init(&sub->service_list);
720 tipc_sub_put(sub);
721
722 /* Delete service item if no more publications and subscriptions */
723 if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) {
724 hlist_del_init_rcu(&sc->service_list);
725 kfree_rcu(sc, rcu);
726 }
727 spin_unlock_bh(&sc->lock);
728exit:
729 spin_unlock_bh(&tn->nametbl_lock);
730}
731
732int tipc_nametbl_init(struct net *net)
733{
734 struct tipc_net *tn = tipc_net(net);
735 struct name_table *nt;
736 int i;
737
738 nt = kzalloc(sizeof(*nt), GFP_KERNEL);
739 if (!nt)
740 return -ENOMEM;
741
742 for (i = 0; i < TIPC_NAMETBL_SIZE; i++)
743 INIT_HLIST_HEAD(&nt->services[i]);
744
745 INIT_LIST_HEAD(&nt->node_scope);
746 INIT_LIST_HEAD(&nt->cluster_scope);
747 rwlock_init(&nt->cluster_scope_lock);
748 tn->nametbl = nt;
749 spin_lock_init(&tn->nametbl_lock);
750 return 0;
751}
752
753/**
754 * tipc_service_delete - purge all publications for a service and delete it
755 */
756static void tipc_service_delete(struct net *net, struct tipc_service *sc)
757{
758 struct service_range *sr, *tmpr;
759 struct publication *p, *tmp;
760
761 spin_lock_bh(&sc->lock);
762 rbtree_postorder_for_each_entry_safe(sr, tmpr, &sc->ranges, tree_node) {
763 list_for_each_entry_safe(p, tmp, &sr->all_publ, all_publ) {
764 tipc_service_remove_publ(sr, p->node, p->key);
765 kfree_rcu(p, rcu);
766 }
767 rb_erase(&sr->tree_node, &sc->ranges);
768 kfree(sr);
769 }
770 hlist_del_init_rcu(&sc->service_list);
771 spin_unlock_bh(&sc->lock);
772 kfree_rcu(sc, rcu);
773}
774
775void tipc_nametbl_stop(struct net *net)
776{
777 struct name_table *nt = tipc_name_table(net);
778 struct tipc_net *tn = tipc_net(net);
779 struct hlist_head *service_head;
780 struct tipc_service *service;
781 u32 i;
782
783 /* Verify name table is empty and purge any lingering
784 * publications, then release the name table
785 */
786 spin_lock_bh(&tn->nametbl_lock);
787 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) {
788 if (hlist_empty(&nt->services[i]))
789 continue;
790 service_head = &nt->services[i];
791 hlist_for_each_entry_rcu(service, service_head, service_list) {
792 tipc_service_delete(net, service);
793 }
794 }
795 spin_unlock_bh(&tn->nametbl_lock);
796
797 synchronize_net();
798 kfree(nt);
799}
800
801static int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg,
802 struct tipc_service *service,
803 struct service_range *sr,
804 u32 *last_key)
805{
806 struct publication *p;
807 struct nlattr *attrs;
808 struct nlattr *b;
809 void *hdr;
810
811 if (*last_key) {
812 list_for_each_entry(p, &sr->all_publ, all_publ)
813 if (p->key == *last_key)
814 break;
815 if (p->key != *last_key)
816 return -EPIPE;
817 } else {
818 p = list_first_entry(&sr->all_publ,
819 struct publication,
820 all_publ);
821 }
822
823 list_for_each_entry_from(p, &sr->all_publ, all_publ) {
824 *last_key = p->key;
825
826 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq,
827 &tipc_genl_family, NLM_F_MULTI,
828 TIPC_NL_NAME_TABLE_GET);
829 if (!hdr)
830 return -EMSGSIZE;
831
832 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE);
833 if (!attrs)
834 goto msg_full;
835
836 b = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE_PUBL);
837 if (!b)
838 goto attr_msg_full;
839
840 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, service->type))
841 goto publ_msg_full;
842 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sr->lower))
843 goto publ_msg_full;
844 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sr->upper))
845 goto publ_msg_full;
846 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope))
847 goto publ_msg_full;
848 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->node))
849 goto publ_msg_full;
850 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->port))
851 goto publ_msg_full;
852 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key))
853 goto publ_msg_full;
854
855 nla_nest_end(msg->skb, b);
856 nla_nest_end(msg->skb, attrs);
857 genlmsg_end(msg->skb, hdr);
858 }
859 *last_key = 0;
860
861 return 0;
862
863publ_msg_full:
864 nla_nest_cancel(msg->skb, b);
865attr_msg_full:
866 nla_nest_cancel(msg->skb, attrs);
867msg_full:
868 genlmsg_cancel(msg->skb, hdr);
869
870 return -EMSGSIZE;
871}
872
873static int __tipc_nl_service_range_list(struct tipc_nl_msg *msg,
874 struct tipc_service *sc,
875 u32 *last_lower, u32 *last_key)
876{
877 struct service_range *sr;
878 struct rb_node *n;
879 int err;
880
881 for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
882 sr = container_of(n, struct service_range, tree_node);
883 if (sr->lower < *last_lower)
884 continue;
885 err = __tipc_nl_add_nametable_publ(msg, sc, sr, last_key);
886 if (err) {
887 *last_lower = sr->lower;
888 return err;
889 }
890 }
891 *last_lower = 0;
892 return 0;
893}
894
895static int tipc_nl_service_list(struct net *net, struct tipc_nl_msg *msg,
896 u32 *last_type, u32 *last_lower, u32 *last_key)
897{
898 struct tipc_net *tn = tipc_net(net);
899 struct tipc_service *service = NULL;
900 struct hlist_head *head;
901 int err;
902 int i;
903
904 if (*last_type)
905 i = hash(*last_type);
906 else
907 i = 0;
908
909 for (; i < TIPC_NAMETBL_SIZE; i++) {
910 head = &tn->nametbl->services[i];
911
912 if (*last_type ||
913 (!i && *last_key && (*last_lower == *last_key))) {
914 service = tipc_service_find(net, *last_type);
915 if (!service)
916 return -EPIPE;
917 } else {
918 hlist_for_each_entry_rcu(service, head, service_list)
919 break;
920 if (!service)
921 continue;
922 }
923
924 hlist_for_each_entry_from_rcu(service, service_list) {
925 spin_lock_bh(&service->lock);
926 err = __tipc_nl_service_range_list(msg, service,
927 last_lower,
928 last_key);
929
930 if (err) {
931 *last_type = service->type;
932 spin_unlock_bh(&service->lock);
933 return err;
934 }
935 spin_unlock_bh(&service->lock);
936 }
937 *last_type = 0;
938 }
939 return 0;
940}
941
942int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb)
943{
944 struct net *net = sock_net(skb->sk);
945 u32 last_type = cb->args[0];
946 u32 last_lower = cb->args[1];
947 u32 last_key = cb->args[2];
948 int done = cb->args[3];
949 struct tipc_nl_msg msg;
950 int err;
951
952 if (done)
953 return 0;
954
955 msg.skb = skb;
956 msg.portid = NETLINK_CB(cb->skb).portid;
957 msg.seq = cb->nlh->nlmsg_seq;
958
959 rcu_read_lock();
960 err = tipc_nl_service_list(net, &msg, &last_type,
961 &last_lower, &last_key);
962 if (!err) {
963 done = 1;
964 } else if (err != -EMSGSIZE) {
965 /* We never set seq or call nl_dump_check_consistent() this
966 * means that setting prev_seq here will cause the consistence
967 * check to fail in the netlink callback handler. Resulting in
968 * the NLMSG_DONE message having the NLM_F_DUMP_INTR flag set if
969 * we got an error.
970 */
971 cb->prev_seq = 1;
972 }
973 rcu_read_unlock();
974
975 cb->args[0] = last_type;
976 cb->args[1] = last_lower;
977 cb->args[2] = last_key;
978 cb->args[3] = done;
979
980 return skb->len;
981}
982
983struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port)
984{
985 struct tipc_dest *dst;
986
987 list_for_each_entry(dst, l, list) {
988 if (dst->node == node && dst->port == port)
989 return dst;
990 }
991 return NULL;
992}
993
994bool tipc_dest_push(struct list_head *l, u32 node, u32 port)
995{
996 struct tipc_dest *dst;
997
998 if (tipc_dest_find(l, node, port))
999 return false;
1000
1001 dst = kmalloc(sizeof(*dst), GFP_ATOMIC);
1002 if (unlikely(!dst))
1003 return false;
1004 dst->node = node;
1005 dst->port = port;
1006 list_add(&dst->list, l);
1007 return true;
1008}
1009
1010bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port)
1011{
1012 struct tipc_dest *dst;
1013
1014 if (list_empty(l))
1015 return false;
1016 dst = list_first_entry(l, typeof(*dst), list);
1017 if (port)
1018 *port = dst->port;
1019 if (node)
1020 *node = dst->node;
1021 list_del(&dst->list);
1022 kfree(dst);
1023 return true;
1024}
1025
1026bool tipc_dest_del(struct list_head *l, u32 node, u32 port)
1027{
1028 struct tipc_dest *dst;
1029
1030 dst = tipc_dest_find(l, node, port);
1031 if (!dst)
1032 return false;
1033 list_del(&dst->list);
1034 kfree(dst);
1035 return true;
1036}
1037
1038void tipc_dest_list_purge(struct list_head *l)
1039{
1040 struct tipc_dest *dst, *tmp;
1041
1042 list_for_each_entry_safe(dst, tmp, l, list) {
1043 list_del(&dst->list);
1044 kfree(dst);
1045 }
1046}
1047
1048int tipc_dest_list_len(struct list_head *l)
1049{
1050 struct tipc_dest *dst;
1051 int i = 0;
1052
1053 list_for_each_entry(dst, l, list) {
1054 i++;
1055 }
1056 return i;
1057}