xref: /linux/net/tipc/node.c (revision 722ecdbce68a87de2d9296f91308f44ea900a039)
1 /*
2  * net/tipc/node.c: TIPC node management routines
3  *
4  * Copyright (c) 2000-2006, 2012-2016, Ericsson AB
5  * Copyright (c) 2005-2006, 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 "core.h"
38 #include "link.h"
39 #include "node.h"
40 #include "name_distr.h"
41 #include "socket.h"
42 #include "bcast.h"
43 #include "monitor.h"
44 #include "discover.h"
45 #include "netlink.h"
46 #include "trace.h"
47 #include "crypto.h"
48 
49 #define INVALID_NODE_SIG	0x10000
50 #define NODE_CLEANUP_AFTER	300000
51 
52 /* Flags used to take different actions according to flag type
53  * TIPC_NOTIFY_NODE_DOWN: notify node is down
54  * TIPC_NOTIFY_NODE_UP: notify node is up
55  * TIPC_DISTRIBUTE_NAME: publish or withdraw link state name type
56  */
57 enum {
58 	TIPC_NOTIFY_NODE_DOWN		= (1 << 3),
59 	TIPC_NOTIFY_NODE_UP		= (1 << 4),
60 	TIPC_NOTIFY_LINK_UP		= (1 << 6),
61 	TIPC_NOTIFY_LINK_DOWN		= (1 << 7)
62 };
63 
64 struct tipc_link_entry {
65 	struct tipc_link *link;
66 	spinlock_t lock; /* per link */
67 	u32 mtu;
68 	struct sk_buff_head inputq;
69 	struct tipc_media_addr maddr;
70 };
71 
72 struct tipc_bclink_entry {
73 	struct tipc_link *link;
74 	struct sk_buff_head inputq1;
75 	struct sk_buff_head arrvq;
76 	struct sk_buff_head inputq2;
77 	struct sk_buff_head namedq;
78 	u16 named_rcv_nxt;
79 	bool named_open;
80 };
81 
82 /**
83  * struct tipc_node - TIPC node structure
84  * @addr: network address of node
85  * @kref: reference counter to node object
86  * @lock: rwlock governing access to structure
87  * @net: the applicable net namespace
88  * @hash: links to adjacent nodes in unsorted hash chain
89  * @inputq: pointer to input queue containing messages for msg event
90  * @namedq: pointer to name table input queue with name table messages
91  * @active_links: bearer ids of active links, used as index into links[] array
92  * @links: array containing references to all links to node
93  * @bc_entry: broadcast link entry
94  * @action_flags: bit mask of different types of node actions
95  * @state: connectivity state vs peer node
96  * @preliminary: a preliminary node or not
97  * @failover_sent: failover sent or not
98  * @sync_point: sequence number where synch/failover is finished
99  * @list: links to adjacent nodes in sorted list of cluster's nodes
100  * @working_links: number of working links to node (both active and standby)
101  * @link_cnt: number of links to node
102  * @capabilities: bitmap, indicating peer node's functional capabilities
103  * @signature: node instance identifier
104  * @link_id: local and remote bearer ids of changing link, if any
105  * @peer_id: 128-bit ID of peer
106  * @peer_id_string: ID string of peer
107  * @publ_list: list of publications
108  * @conn_sks: list of connections (FIXME)
109  * @timer: node's keepalive timer
110  * @keepalive_intv: keepalive interval in milliseconds
111  * @rcu: rcu struct for tipc_node
112  * @delete_at: indicates the time for deleting a down node
113  * @peer_net: peer's net namespace
114  * @peer_hash_mix: hash for this peer (FIXME)
115  * @crypto_rx: RX crypto handler
116  */
117 struct tipc_node {
118 	u32 addr;
119 	struct kref kref;
120 	rwlock_t lock;
121 	struct net *net;
122 	struct hlist_node hash;
123 	int active_links[2];
124 	struct tipc_link_entry links[MAX_BEARERS];
125 	struct tipc_bclink_entry bc_entry;
126 	int action_flags;
127 	struct list_head list;
128 	int state;
129 	bool preliminary;
130 	bool failover_sent;
131 	u16 sync_point;
132 	int link_cnt;
133 	u16 working_links;
134 	u16 capabilities;
135 	u32 signature;
136 	u32 link_id;
137 	u8 peer_id[16];
138 	char peer_id_string[NODE_ID_STR_LEN];
139 	struct list_head publ_list;
140 	struct list_head conn_sks;
141 	unsigned long keepalive_intv;
142 	struct timer_list timer;
143 	struct rcu_head rcu;
144 	unsigned long delete_at;
145 	struct net *peer_net;
146 	u32 peer_hash_mix;
147 #ifdef CONFIG_TIPC_CRYPTO
148 	struct tipc_crypto *crypto_rx;
149 #endif
150 };
151 
152 /* Node FSM states and events:
153  */
154 enum {
155 	SELF_DOWN_PEER_DOWN    = 0xdd,
156 	SELF_UP_PEER_UP        = 0xaa,
157 	SELF_DOWN_PEER_LEAVING = 0xd1,
158 	SELF_UP_PEER_COMING    = 0xac,
159 	SELF_COMING_PEER_UP    = 0xca,
160 	SELF_LEAVING_PEER_DOWN = 0x1d,
161 	NODE_FAILINGOVER       = 0xf0,
162 	NODE_SYNCHING          = 0xcc
163 };
164 
165 enum {
166 	SELF_ESTABL_CONTACT_EVT = 0xece,
167 	SELF_LOST_CONTACT_EVT   = 0x1ce,
168 	PEER_ESTABL_CONTACT_EVT = 0x9ece,
169 	PEER_LOST_CONTACT_EVT   = 0x91ce,
170 	NODE_FAILOVER_BEGIN_EVT = 0xfbe,
171 	NODE_FAILOVER_END_EVT   = 0xfee,
172 	NODE_SYNCH_BEGIN_EVT    = 0xcbe,
173 	NODE_SYNCH_END_EVT      = 0xcee
174 };
175 
176 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
177 				  struct sk_buff_head *xmitq,
178 				  struct tipc_media_addr **maddr);
179 static void tipc_node_link_down(struct tipc_node *n, int bearer_id,
180 				bool delete);
181 static void node_lost_contact(struct tipc_node *n, struct sk_buff_head *inputq);
182 static void tipc_node_delete(struct tipc_node *node);
183 static void tipc_node_timeout(struct timer_list *t);
184 static void tipc_node_fsm_evt(struct tipc_node *n, int evt);
185 static struct tipc_node *tipc_node_find(struct net *net, u32 addr);
186 static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id);
187 static bool node_is_up(struct tipc_node *n);
188 static void tipc_node_delete_from_list(struct tipc_node *node);
189 
190 struct tipc_sock_conn {
191 	u32 port;
192 	u32 peer_port;
193 	u32 peer_node;
194 	struct list_head list;
195 };
196 
197 static struct tipc_link *node_active_link(struct tipc_node *n, int sel)
198 {
199 	int bearer_id = n->active_links[sel & 1];
200 
201 	if (unlikely(bearer_id == INVALID_BEARER_ID))
202 		return NULL;
203 
204 	return n->links[bearer_id].link;
205 }
206 
207 int tipc_node_get_mtu(struct net *net, u32 addr, u32 sel, bool connected)
208 {
209 	struct tipc_node *n;
210 	int bearer_id;
211 	unsigned int mtu = MAX_MSG_SIZE;
212 
213 	n = tipc_node_find(net, addr);
214 	if (unlikely(!n))
215 		return mtu;
216 
217 	/* Allow MAX_MSG_SIZE when building connection oriented message
218 	 * if they are in the same core network
219 	 */
220 	if (n->peer_net && connected) {
221 		tipc_node_put(n);
222 		return mtu;
223 	}
224 
225 	bearer_id = n->active_links[sel & 1];
226 	if (likely(bearer_id != INVALID_BEARER_ID))
227 		mtu = n->links[bearer_id].mtu;
228 	tipc_node_put(n);
229 	return mtu;
230 }
231 
232 bool tipc_node_get_id(struct net *net, u32 addr, u8 *id)
233 {
234 	u8 *own_id = tipc_own_id(net);
235 	struct tipc_node *n;
236 
237 	if (!own_id)
238 		return true;
239 
240 	if (addr == tipc_own_addr(net)) {
241 		memcpy(id, own_id, TIPC_NODEID_LEN);
242 		return true;
243 	}
244 	n = tipc_node_find(net, addr);
245 	if (!n)
246 		return false;
247 
248 	memcpy(id, &n->peer_id, TIPC_NODEID_LEN);
249 	tipc_node_put(n);
250 	return true;
251 }
252 
253 u16 tipc_node_get_capabilities(struct net *net, u32 addr)
254 {
255 	struct tipc_node *n;
256 	u16 caps;
257 
258 	n = tipc_node_find(net, addr);
259 	if (unlikely(!n))
260 		return TIPC_NODE_CAPABILITIES;
261 	caps = n->capabilities;
262 	tipc_node_put(n);
263 	return caps;
264 }
265 
266 u32 tipc_node_get_addr(struct tipc_node *node)
267 {
268 	return (node) ? node->addr : 0;
269 }
270 
271 char *tipc_node_get_id_str(struct tipc_node *node)
272 {
273 	return node->peer_id_string;
274 }
275 
276 #ifdef CONFIG_TIPC_CRYPTO
277 /**
278  * tipc_node_crypto_rx - Retrieve crypto RX handle from node
279  * @__n: target tipc_node
280  * Note: node ref counter must be held first!
281  */
282 struct tipc_crypto *tipc_node_crypto_rx(struct tipc_node *__n)
283 {
284 	return (__n) ? __n->crypto_rx : NULL;
285 }
286 
287 struct tipc_crypto *tipc_node_crypto_rx_by_list(struct list_head *pos)
288 {
289 	return container_of(pos, struct tipc_node, list)->crypto_rx;
290 }
291 
292 struct tipc_crypto *tipc_node_crypto_rx_by_addr(struct net *net, u32 addr)
293 {
294 	struct tipc_node *n;
295 
296 	n = tipc_node_find(net, addr);
297 	return (n) ? n->crypto_rx : NULL;
298 }
299 #endif
300 
301 static void tipc_node_free(struct rcu_head *rp)
302 {
303 	struct tipc_node *n = container_of(rp, struct tipc_node, rcu);
304 
305 #ifdef CONFIG_TIPC_CRYPTO
306 	tipc_crypto_stop(&n->crypto_rx);
307 #endif
308 	kfree(n);
309 }
310 
311 static void tipc_node_kref_release(struct kref *kref)
312 {
313 	struct tipc_node *n = container_of(kref, struct tipc_node, kref);
314 
315 	kfree(n->bc_entry.link);
316 	call_rcu(&n->rcu, tipc_node_free);
317 }
318 
319 void tipc_node_put(struct tipc_node *node)
320 {
321 	kref_put(&node->kref, tipc_node_kref_release);
322 }
323 
324 void tipc_node_get(struct tipc_node *node)
325 {
326 	kref_get(&node->kref);
327 }
328 
329 /*
330  * tipc_node_find - locate specified node object, if it exists
331  */
332 static struct tipc_node *tipc_node_find(struct net *net, u32 addr)
333 {
334 	struct tipc_net *tn = tipc_net(net);
335 	struct tipc_node *node;
336 	unsigned int thash = tipc_hashfn(addr);
337 
338 	rcu_read_lock();
339 	hlist_for_each_entry_rcu(node, &tn->node_htable[thash], hash) {
340 		if (node->addr != addr || node->preliminary)
341 			continue;
342 		if (!kref_get_unless_zero(&node->kref))
343 			node = NULL;
344 		break;
345 	}
346 	rcu_read_unlock();
347 	return node;
348 }
349 
350 /* tipc_node_find_by_id - locate specified node object by its 128-bit id
351  * Note: this function is called only when a discovery request failed
352  * to find the node by its 32-bit id, and is not time critical
353  */
354 static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id)
355 {
356 	struct tipc_net *tn = tipc_net(net);
357 	struct tipc_node *n;
358 	bool found = false;
359 
360 	rcu_read_lock();
361 	list_for_each_entry_rcu(n, &tn->node_list, list) {
362 		read_lock_bh(&n->lock);
363 		if (!memcmp(id, n->peer_id, 16) &&
364 		    kref_get_unless_zero(&n->kref))
365 			found = true;
366 		read_unlock_bh(&n->lock);
367 		if (found)
368 			break;
369 	}
370 	rcu_read_unlock();
371 	return found ? n : NULL;
372 }
373 
374 static void tipc_node_read_lock(struct tipc_node *n)
375 	__acquires(n->lock)
376 {
377 	read_lock_bh(&n->lock);
378 }
379 
380 static void tipc_node_read_unlock(struct tipc_node *n)
381 	__releases(n->lock)
382 {
383 	read_unlock_bh(&n->lock);
384 }
385 
386 static void tipc_node_write_lock(struct tipc_node *n)
387 	__acquires(n->lock)
388 {
389 	write_lock_bh(&n->lock);
390 }
391 
392 static void tipc_node_write_unlock_fast(struct tipc_node *n)
393 	__releases(n->lock)
394 {
395 	write_unlock_bh(&n->lock);
396 }
397 
398 static void tipc_node_write_unlock(struct tipc_node *n)
399 	__releases(n->lock)
400 {
401 	struct tipc_socket_addr sk;
402 	struct net *net = n->net;
403 	u32 flags = n->action_flags;
404 	struct list_head *publ_list;
405 	struct tipc_uaddr ua;
406 	u32 bearer_id, node;
407 
408 	if (likely(!flags)) {
409 		write_unlock_bh(&n->lock);
410 		return;
411 	}
412 
413 	tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_NODE_SCOPE,
414 		   TIPC_LINK_STATE, n->addr, n->addr);
415 	sk.ref = n->link_id;
416 	sk.node = tipc_own_addr(net);
417 	node = n->addr;
418 	bearer_id = n->link_id & 0xffff;
419 	publ_list = &n->publ_list;
420 
421 	n->action_flags &= ~(TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP |
422 			     TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP);
423 
424 	write_unlock_bh(&n->lock);
425 
426 	if (flags & TIPC_NOTIFY_NODE_DOWN)
427 		tipc_publ_notify(net, publ_list, node, n->capabilities);
428 
429 	if (flags & TIPC_NOTIFY_NODE_UP)
430 		tipc_named_node_up(net, node, n->capabilities);
431 
432 	if (flags & TIPC_NOTIFY_LINK_UP) {
433 		tipc_mon_peer_up(net, node, bearer_id);
434 		tipc_nametbl_publish(net, &ua, &sk, sk.ref);
435 	}
436 	if (flags & TIPC_NOTIFY_LINK_DOWN) {
437 		tipc_mon_peer_down(net, node, bearer_id);
438 		tipc_nametbl_withdraw(net, &ua, &sk, sk.ref);
439 	}
440 }
441 
442 static void tipc_node_assign_peer_net(struct tipc_node *n, u32 hash_mixes)
443 {
444 	int net_id = tipc_netid(n->net);
445 	struct tipc_net *tn_peer;
446 	struct net *tmp;
447 	u32 hash_chk;
448 
449 	if (n->peer_net)
450 		return;
451 
452 	for_each_net_rcu(tmp) {
453 		tn_peer = tipc_net(tmp);
454 		if (!tn_peer)
455 			continue;
456 		/* Integrity checking whether node exists in namespace or not */
457 		if (tn_peer->net_id != net_id)
458 			continue;
459 		if (memcmp(n->peer_id, tn_peer->node_id, NODE_ID_LEN))
460 			continue;
461 		hash_chk = tipc_net_hash_mixes(tmp, tn_peer->random);
462 		if (hash_mixes ^ hash_chk)
463 			continue;
464 		n->peer_net = tmp;
465 		n->peer_hash_mix = hash_mixes;
466 		break;
467 	}
468 }
469 
470 struct tipc_node *tipc_node_create(struct net *net, u32 addr, u8 *peer_id,
471 				   u16 capabilities, u32 hash_mixes,
472 				   bool preliminary)
473 {
474 	struct tipc_net *tn = net_generic(net, tipc_net_id);
475 	struct tipc_node *n, *temp_node;
476 	struct tipc_link *l;
477 	unsigned long intv;
478 	int bearer_id;
479 	int i;
480 
481 	spin_lock_bh(&tn->node_list_lock);
482 	n = tipc_node_find(net, addr) ?:
483 		tipc_node_find_by_id(net, peer_id);
484 	if (n) {
485 		if (!n->preliminary)
486 			goto update;
487 		if (preliminary)
488 			goto exit;
489 		/* A preliminary node becomes "real" now, refresh its data */
490 		tipc_node_write_lock(n);
491 		n->preliminary = false;
492 		n->addr = addr;
493 		hlist_del_rcu(&n->hash);
494 		hlist_add_head_rcu(&n->hash,
495 				   &tn->node_htable[tipc_hashfn(addr)]);
496 		list_del_rcu(&n->list);
497 		list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
498 			if (n->addr < temp_node->addr)
499 				break;
500 		}
501 		list_add_tail_rcu(&n->list, &temp_node->list);
502 		tipc_node_write_unlock_fast(n);
503 
504 update:
505 		if (n->peer_hash_mix ^ hash_mixes)
506 			tipc_node_assign_peer_net(n, hash_mixes);
507 		if (n->capabilities == capabilities)
508 			goto exit;
509 		/* Same node may come back with new capabilities */
510 		tipc_node_write_lock(n);
511 		n->capabilities = capabilities;
512 		for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
513 			l = n->links[bearer_id].link;
514 			if (l)
515 				tipc_link_update_caps(l, capabilities);
516 		}
517 		tipc_node_write_unlock_fast(n);
518 
519 		/* Calculate cluster capabilities */
520 		tn->capabilities = TIPC_NODE_CAPABILITIES;
521 		list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
522 			tn->capabilities &= temp_node->capabilities;
523 		}
524 
525 		tipc_bcast_toggle_rcast(net,
526 					(tn->capabilities & TIPC_BCAST_RCAST));
527 
528 		goto exit;
529 	}
530 	n = kzalloc(sizeof(*n), GFP_ATOMIC);
531 	if (!n) {
532 		pr_warn("Node creation failed, no memory\n");
533 		goto exit;
534 	}
535 	tipc_nodeid2string(n->peer_id_string, peer_id);
536 #ifdef CONFIG_TIPC_CRYPTO
537 	if (unlikely(tipc_crypto_start(&n->crypto_rx, net, n))) {
538 		pr_warn("Failed to start crypto RX(%s)!\n", n->peer_id_string);
539 		kfree(n);
540 		n = NULL;
541 		goto exit;
542 	}
543 #endif
544 	n->addr = addr;
545 	n->preliminary = preliminary;
546 	memcpy(&n->peer_id, peer_id, 16);
547 	n->net = net;
548 	n->peer_net = NULL;
549 	n->peer_hash_mix = 0;
550 	/* Assign kernel local namespace if exists */
551 	tipc_node_assign_peer_net(n, hash_mixes);
552 	n->capabilities = capabilities;
553 	kref_init(&n->kref);
554 	rwlock_init(&n->lock);
555 	INIT_HLIST_NODE(&n->hash);
556 	INIT_LIST_HEAD(&n->list);
557 	INIT_LIST_HEAD(&n->publ_list);
558 	INIT_LIST_HEAD(&n->conn_sks);
559 	skb_queue_head_init(&n->bc_entry.namedq);
560 	skb_queue_head_init(&n->bc_entry.inputq1);
561 	__skb_queue_head_init(&n->bc_entry.arrvq);
562 	skb_queue_head_init(&n->bc_entry.inputq2);
563 	for (i = 0; i < MAX_BEARERS; i++)
564 		spin_lock_init(&n->links[i].lock);
565 	n->state = SELF_DOWN_PEER_LEAVING;
566 	n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
567 	n->signature = INVALID_NODE_SIG;
568 	n->active_links[0] = INVALID_BEARER_ID;
569 	n->active_links[1] = INVALID_BEARER_ID;
570 	n->bc_entry.link = NULL;
571 	tipc_node_get(n);
572 	timer_setup(&n->timer, tipc_node_timeout, 0);
573 	/* Start a slow timer anyway, crypto needs it */
574 	n->keepalive_intv = 10000;
575 	intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
576 	if (!mod_timer(&n->timer, intv))
577 		tipc_node_get(n);
578 	hlist_add_head_rcu(&n->hash, &tn->node_htable[tipc_hashfn(addr)]);
579 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
580 		if (n->addr < temp_node->addr)
581 			break;
582 	}
583 	list_add_tail_rcu(&n->list, &temp_node->list);
584 	/* Calculate cluster capabilities */
585 	tn->capabilities = TIPC_NODE_CAPABILITIES;
586 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
587 		tn->capabilities &= temp_node->capabilities;
588 	}
589 	tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
590 	trace_tipc_node_create(n, true, " ");
591 exit:
592 	spin_unlock_bh(&tn->node_list_lock);
593 	return n;
594 }
595 
596 static void tipc_node_calculate_timer(struct tipc_node *n, struct tipc_link *l)
597 {
598 	unsigned long tol = tipc_link_tolerance(l);
599 	unsigned long intv = ((tol / 4) > 500) ? 500 : tol / 4;
600 
601 	/* Link with lowest tolerance determines timer interval */
602 	if (intv < n->keepalive_intv)
603 		n->keepalive_intv = intv;
604 
605 	/* Ensure link's abort limit corresponds to current tolerance */
606 	tipc_link_set_abort_limit(l, tol / n->keepalive_intv);
607 }
608 
609 static void tipc_node_delete_from_list(struct tipc_node *node)
610 {
611 #ifdef CONFIG_TIPC_CRYPTO
612 	tipc_crypto_key_flush(node->crypto_rx);
613 #endif
614 	list_del_rcu(&node->list);
615 	hlist_del_rcu(&node->hash);
616 	tipc_node_put(node);
617 }
618 
619 static void tipc_node_delete(struct tipc_node *node)
620 {
621 	trace_tipc_node_delete(node, true, " ");
622 	tipc_node_delete_from_list(node);
623 
624 	del_timer_sync(&node->timer);
625 	tipc_node_put(node);
626 }
627 
628 void tipc_node_stop(struct net *net)
629 {
630 	struct tipc_net *tn = tipc_net(net);
631 	struct tipc_node *node, *t_node;
632 
633 	spin_lock_bh(&tn->node_list_lock);
634 	list_for_each_entry_safe(node, t_node, &tn->node_list, list)
635 		tipc_node_delete(node);
636 	spin_unlock_bh(&tn->node_list_lock);
637 }
638 
639 void tipc_node_subscribe(struct net *net, struct list_head *subscr, u32 addr)
640 {
641 	struct tipc_node *n;
642 
643 	if (in_own_node(net, addr))
644 		return;
645 
646 	n = tipc_node_find(net, addr);
647 	if (!n) {
648 		pr_warn("Node subscribe rejected, unknown node 0x%x\n", addr);
649 		return;
650 	}
651 	tipc_node_write_lock(n);
652 	list_add_tail(subscr, &n->publ_list);
653 	tipc_node_write_unlock_fast(n);
654 	tipc_node_put(n);
655 }
656 
657 void tipc_node_unsubscribe(struct net *net, struct list_head *subscr, u32 addr)
658 {
659 	struct tipc_node *n;
660 
661 	if (in_own_node(net, addr))
662 		return;
663 
664 	n = tipc_node_find(net, addr);
665 	if (!n) {
666 		pr_warn("Node unsubscribe rejected, unknown node 0x%x\n", addr);
667 		return;
668 	}
669 	tipc_node_write_lock(n);
670 	list_del_init(subscr);
671 	tipc_node_write_unlock_fast(n);
672 	tipc_node_put(n);
673 }
674 
675 int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port)
676 {
677 	struct tipc_node *node;
678 	struct tipc_sock_conn *conn;
679 	int err = 0;
680 
681 	if (in_own_node(net, dnode))
682 		return 0;
683 
684 	node = tipc_node_find(net, dnode);
685 	if (!node) {
686 		pr_warn("Connecting sock to node 0x%x failed\n", dnode);
687 		return -EHOSTUNREACH;
688 	}
689 	conn = kmalloc(sizeof(*conn), GFP_ATOMIC);
690 	if (!conn) {
691 		err = -EHOSTUNREACH;
692 		goto exit;
693 	}
694 	conn->peer_node = dnode;
695 	conn->port = port;
696 	conn->peer_port = peer_port;
697 
698 	tipc_node_write_lock(node);
699 	list_add_tail(&conn->list, &node->conn_sks);
700 	tipc_node_write_unlock(node);
701 exit:
702 	tipc_node_put(node);
703 	return err;
704 }
705 
706 void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port)
707 {
708 	struct tipc_node *node;
709 	struct tipc_sock_conn *conn, *safe;
710 
711 	if (in_own_node(net, dnode))
712 		return;
713 
714 	node = tipc_node_find(net, dnode);
715 	if (!node)
716 		return;
717 
718 	tipc_node_write_lock(node);
719 	list_for_each_entry_safe(conn, safe, &node->conn_sks, list) {
720 		if (port != conn->port)
721 			continue;
722 		list_del(&conn->list);
723 		kfree(conn);
724 	}
725 	tipc_node_write_unlock(node);
726 	tipc_node_put(node);
727 }
728 
729 static void  tipc_node_clear_links(struct tipc_node *node)
730 {
731 	int i;
732 
733 	for (i = 0; i < MAX_BEARERS; i++) {
734 		struct tipc_link_entry *le = &node->links[i];
735 
736 		if (le->link) {
737 			kfree(le->link);
738 			le->link = NULL;
739 			node->link_cnt--;
740 		}
741 	}
742 }
743 
744 /* tipc_node_cleanup - delete nodes that does not
745  * have active links for NODE_CLEANUP_AFTER time
746  */
747 static bool tipc_node_cleanup(struct tipc_node *peer)
748 {
749 	struct tipc_node *temp_node;
750 	struct tipc_net *tn = tipc_net(peer->net);
751 	bool deleted = false;
752 
753 	/* If lock held by tipc_node_stop() the node will be deleted anyway */
754 	if (!spin_trylock_bh(&tn->node_list_lock))
755 		return false;
756 
757 	tipc_node_write_lock(peer);
758 
759 	if (!node_is_up(peer) && time_after(jiffies, peer->delete_at)) {
760 		tipc_node_clear_links(peer);
761 		tipc_node_delete_from_list(peer);
762 		deleted = true;
763 	}
764 	tipc_node_write_unlock(peer);
765 
766 	if (!deleted) {
767 		spin_unlock_bh(&tn->node_list_lock);
768 		return deleted;
769 	}
770 
771 	/* Calculate cluster capabilities */
772 	tn->capabilities = TIPC_NODE_CAPABILITIES;
773 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
774 		tn->capabilities &= temp_node->capabilities;
775 	}
776 	tipc_bcast_toggle_rcast(peer->net,
777 				(tn->capabilities & TIPC_BCAST_RCAST));
778 	spin_unlock_bh(&tn->node_list_lock);
779 	return deleted;
780 }
781 
782 /* tipc_node_timeout - handle expiration of node timer
783  */
784 static void tipc_node_timeout(struct timer_list *t)
785 {
786 	struct tipc_node *n = from_timer(n, t, timer);
787 	struct tipc_link_entry *le;
788 	struct sk_buff_head xmitq;
789 	int remains = n->link_cnt;
790 	int bearer_id;
791 	int rc = 0;
792 
793 	trace_tipc_node_timeout(n, false, " ");
794 	if (!node_is_up(n) && tipc_node_cleanup(n)) {
795 		/*Removing the reference of Timer*/
796 		tipc_node_put(n);
797 		return;
798 	}
799 
800 #ifdef CONFIG_TIPC_CRYPTO
801 	/* Take any crypto key related actions first */
802 	tipc_crypto_timeout(n->crypto_rx);
803 #endif
804 	__skb_queue_head_init(&xmitq);
805 
806 	/* Initial node interval to value larger (10 seconds), then it will be
807 	 * recalculated with link lowest tolerance
808 	 */
809 	tipc_node_read_lock(n);
810 	n->keepalive_intv = 10000;
811 	tipc_node_read_unlock(n);
812 	for (bearer_id = 0; remains && (bearer_id < MAX_BEARERS); bearer_id++) {
813 		tipc_node_read_lock(n);
814 		le = &n->links[bearer_id];
815 		if (le->link) {
816 			spin_lock_bh(&le->lock);
817 			/* Link tolerance may change asynchronously: */
818 			tipc_node_calculate_timer(n, le->link);
819 			rc = tipc_link_timeout(le->link, &xmitq);
820 			spin_unlock_bh(&le->lock);
821 			remains--;
822 		}
823 		tipc_node_read_unlock(n);
824 		tipc_bearer_xmit(n->net, bearer_id, &xmitq, &le->maddr, n);
825 		if (rc & TIPC_LINK_DOWN_EVT)
826 			tipc_node_link_down(n, bearer_id, false);
827 	}
828 	mod_timer(&n->timer, jiffies + msecs_to_jiffies(n->keepalive_intv));
829 }
830 
831 /**
832  * __tipc_node_link_up - handle addition of link
833  * @n: target tipc_node
834  * @bearer_id: id of the bearer
835  * @xmitq: queue for messages to be xmited on
836  * Node lock must be held by caller
837  * Link becomes active (alone or shared) or standby, depending on its priority.
838  */
839 static void __tipc_node_link_up(struct tipc_node *n, int bearer_id,
840 				struct sk_buff_head *xmitq)
841 {
842 	int *slot0 = &n->active_links[0];
843 	int *slot1 = &n->active_links[1];
844 	struct tipc_link *ol = node_active_link(n, 0);
845 	struct tipc_link *nl = n->links[bearer_id].link;
846 
847 	if (!nl || tipc_link_is_up(nl))
848 		return;
849 
850 	tipc_link_fsm_evt(nl, LINK_ESTABLISH_EVT);
851 	if (!tipc_link_is_up(nl))
852 		return;
853 
854 	n->working_links++;
855 	n->action_flags |= TIPC_NOTIFY_LINK_UP;
856 	n->link_id = tipc_link_id(nl);
857 
858 	/* Leave room for tunnel header when returning 'mtu' to users: */
859 	n->links[bearer_id].mtu = tipc_link_mss(nl);
860 
861 	tipc_bearer_add_dest(n->net, bearer_id, n->addr);
862 	tipc_bcast_inc_bearer_dst_cnt(n->net, bearer_id);
863 
864 	pr_debug("Established link <%s> on network plane %c\n",
865 		 tipc_link_name(nl), tipc_link_plane(nl));
866 	trace_tipc_node_link_up(n, true, " ");
867 
868 	/* Ensure that a STATE message goes first */
869 	tipc_link_build_state_msg(nl, xmitq);
870 
871 	/* First link? => give it both slots */
872 	if (!ol) {
873 		*slot0 = bearer_id;
874 		*slot1 = bearer_id;
875 		tipc_node_fsm_evt(n, SELF_ESTABL_CONTACT_EVT);
876 		n->action_flags |= TIPC_NOTIFY_NODE_UP;
877 		tipc_link_set_active(nl, true);
878 		tipc_bcast_add_peer(n->net, nl, xmitq);
879 		return;
880 	}
881 
882 	/* Second link => redistribute slots */
883 	if (tipc_link_prio(nl) > tipc_link_prio(ol)) {
884 		pr_debug("Old link <%s> becomes standby\n", tipc_link_name(ol));
885 		*slot0 = bearer_id;
886 		*slot1 = bearer_id;
887 		tipc_link_set_active(nl, true);
888 		tipc_link_set_active(ol, false);
889 	} else if (tipc_link_prio(nl) == tipc_link_prio(ol)) {
890 		tipc_link_set_active(nl, true);
891 		*slot1 = bearer_id;
892 	} else {
893 		pr_debug("New link <%s> is standby\n", tipc_link_name(nl));
894 	}
895 
896 	/* Prepare synchronization with first link */
897 	tipc_link_tnl_prepare(ol, nl, SYNCH_MSG, xmitq);
898 }
899 
900 /**
901  * tipc_node_link_up - handle addition of link
902  * @n: target tipc_node
903  * @bearer_id: id of the bearer
904  * @xmitq: queue for messages to be xmited on
905  *
906  * Link becomes active (alone or shared) or standby, depending on its priority.
907  */
908 static void tipc_node_link_up(struct tipc_node *n, int bearer_id,
909 			      struct sk_buff_head *xmitq)
910 {
911 	struct tipc_media_addr *maddr;
912 
913 	tipc_node_write_lock(n);
914 	__tipc_node_link_up(n, bearer_id, xmitq);
915 	maddr = &n->links[bearer_id].maddr;
916 	tipc_bearer_xmit(n->net, bearer_id, xmitq, maddr, n);
917 	tipc_node_write_unlock(n);
918 }
919 
920 /**
921  * tipc_node_link_failover() - start failover in case "half-failover"
922  *
923  * This function is only called in a very special situation where link
924  * failover can be already started on peer node but not on this node.
925  * This can happen when e.g.::
926  *
927  *	1. Both links <1A-2A>, <1B-2B> down
928  *	2. Link endpoint 2A up, but 1A still down (e.g. due to network
929  *	disturbance, wrong session, etc.)
930  *	3. Link <1B-2B> up
931  *	4. Link endpoint 2A down (e.g. due to link tolerance timeout)
932  *	5. Node 2 starts failover onto link <1B-2B>
933  *
934  *	==> Node 1 does never start link/node failover!
935  *
936  * @n: tipc node structure
937  * @l: link peer endpoint failingover (- can be NULL)
938  * @tnl: tunnel link
939  * @xmitq: queue for messages to be xmited on tnl link later
940  */
941 static void tipc_node_link_failover(struct tipc_node *n, struct tipc_link *l,
942 				    struct tipc_link *tnl,
943 				    struct sk_buff_head *xmitq)
944 {
945 	/* Avoid to be "self-failover" that can never end */
946 	if (!tipc_link_is_up(tnl))
947 		return;
948 
949 	/* Don't rush, failure link may be in the process of resetting */
950 	if (l && !tipc_link_is_reset(l))
951 		return;
952 
953 	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
954 	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
955 
956 	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
957 	tipc_link_failover_prepare(l, tnl, xmitq);
958 
959 	if (l)
960 		tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
961 	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
962 }
963 
964 /**
965  * __tipc_node_link_down - handle loss of link
966  * @n: target tipc_node
967  * @bearer_id: id of the bearer
968  * @xmitq: queue for messages to be xmited on
969  * @maddr: output media address of the bearer
970  */
971 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
972 				  struct sk_buff_head *xmitq,
973 				  struct tipc_media_addr **maddr)
974 {
975 	struct tipc_link_entry *le = &n->links[*bearer_id];
976 	int *slot0 = &n->active_links[0];
977 	int *slot1 = &n->active_links[1];
978 	int i, highest = 0, prio;
979 	struct tipc_link *l, *_l, *tnl;
980 
981 	l = n->links[*bearer_id].link;
982 	if (!l || tipc_link_is_reset(l))
983 		return;
984 
985 	n->working_links--;
986 	n->action_flags |= TIPC_NOTIFY_LINK_DOWN;
987 	n->link_id = tipc_link_id(l);
988 
989 	tipc_bearer_remove_dest(n->net, *bearer_id, n->addr);
990 
991 	pr_debug("Lost link <%s> on network plane %c\n",
992 		 tipc_link_name(l), tipc_link_plane(l));
993 
994 	/* Select new active link if any available */
995 	*slot0 = INVALID_BEARER_ID;
996 	*slot1 = INVALID_BEARER_ID;
997 	for (i = 0; i < MAX_BEARERS; i++) {
998 		_l = n->links[i].link;
999 		if (!_l || !tipc_link_is_up(_l))
1000 			continue;
1001 		if (_l == l)
1002 			continue;
1003 		prio = tipc_link_prio(_l);
1004 		if (prio < highest)
1005 			continue;
1006 		if (prio > highest) {
1007 			highest = prio;
1008 			*slot0 = i;
1009 			*slot1 = i;
1010 			continue;
1011 		}
1012 		*slot1 = i;
1013 	}
1014 
1015 	if (!node_is_up(n)) {
1016 		if (tipc_link_peer_is_down(l))
1017 			tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
1018 		tipc_node_fsm_evt(n, SELF_LOST_CONTACT_EVT);
1019 		trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down!");
1020 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1021 		tipc_link_reset(l);
1022 		tipc_link_build_reset_msg(l, xmitq);
1023 		*maddr = &n->links[*bearer_id].maddr;
1024 		node_lost_contact(n, &le->inputq);
1025 		tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
1026 		return;
1027 	}
1028 	tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
1029 
1030 	/* There is still a working link => initiate failover */
1031 	*bearer_id = n->active_links[0];
1032 	tnl = n->links[*bearer_id].link;
1033 	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
1034 	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
1035 	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
1036 	tipc_link_tnl_prepare(l, tnl, FAILOVER_MSG, xmitq);
1037 	trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down -> failover!");
1038 	tipc_link_reset(l);
1039 	tipc_link_fsm_evt(l, LINK_RESET_EVT);
1040 	tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
1041 	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
1042 	*maddr = &n->links[*bearer_id].maddr;
1043 }
1044 
1045 static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete)
1046 {
1047 	struct tipc_link_entry *le = &n->links[bearer_id];
1048 	struct tipc_media_addr *maddr = NULL;
1049 	struct tipc_link *l = le->link;
1050 	int old_bearer_id = bearer_id;
1051 	struct sk_buff_head xmitq;
1052 
1053 	if (!l)
1054 		return;
1055 
1056 	__skb_queue_head_init(&xmitq);
1057 
1058 	tipc_node_write_lock(n);
1059 	if (!tipc_link_is_establishing(l)) {
1060 		__tipc_node_link_down(n, &bearer_id, &xmitq, &maddr);
1061 	} else {
1062 		/* Defuse pending tipc_node_link_up() */
1063 		tipc_link_reset(l);
1064 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1065 	}
1066 	if (delete) {
1067 		kfree(l);
1068 		le->link = NULL;
1069 		n->link_cnt--;
1070 	}
1071 	trace_tipc_node_link_down(n, true, "node link down or deleted!");
1072 	tipc_node_write_unlock(n);
1073 	if (delete)
1074 		tipc_mon_remove_peer(n->net, n->addr, old_bearer_id);
1075 	if (!skb_queue_empty(&xmitq))
1076 		tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr, n);
1077 	tipc_sk_rcv(n->net, &le->inputq);
1078 }
1079 
1080 static bool node_is_up(struct tipc_node *n)
1081 {
1082 	return n->active_links[0] != INVALID_BEARER_ID;
1083 }
1084 
1085 bool tipc_node_is_up(struct net *net, u32 addr)
1086 {
1087 	struct tipc_node *n;
1088 	bool retval = false;
1089 
1090 	if (in_own_node(net, addr))
1091 		return true;
1092 
1093 	n = tipc_node_find(net, addr);
1094 	if (!n)
1095 		return false;
1096 	retval = node_is_up(n);
1097 	tipc_node_put(n);
1098 	return retval;
1099 }
1100 
1101 static u32 tipc_node_suggest_addr(struct net *net, u32 addr)
1102 {
1103 	struct tipc_node *n;
1104 
1105 	addr ^= tipc_net(net)->random;
1106 	while ((n = tipc_node_find(net, addr))) {
1107 		tipc_node_put(n);
1108 		addr++;
1109 	}
1110 	return addr;
1111 }
1112 
1113 /* tipc_node_try_addr(): Check if addr can be used by peer, suggest other if not
1114  * Returns suggested address if any, otherwise 0
1115  */
1116 u32 tipc_node_try_addr(struct net *net, u8 *id, u32 addr)
1117 {
1118 	struct tipc_net *tn = tipc_net(net);
1119 	struct tipc_node *n;
1120 	bool preliminary;
1121 	u32 sugg_addr;
1122 
1123 	/* Suggest new address if some other peer is using this one */
1124 	n = tipc_node_find(net, addr);
1125 	if (n) {
1126 		if (!memcmp(n->peer_id, id, NODE_ID_LEN))
1127 			addr = 0;
1128 		tipc_node_put(n);
1129 		if (!addr)
1130 			return 0;
1131 		return tipc_node_suggest_addr(net, addr);
1132 	}
1133 
1134 	/* Suggest previously used address if peer is known */
1135 	n = tipc_node_find_by_id(net, id);
1136 	if (n) {
1137 		sugg_addr = n->addr;
1138 		preliminary = n->preliminary;
1139 		tipc_node_put(n);
1140 		if (!preliminary)
1141 			return sugg_addr;
1142 	}
1143 
1144 	/* Even this node may be in conflict */
1145 	if (tn->trial_addr == addr)
1146 		return tipc_node_suggest_addr(net, addr);
1147 
1148 	return 0;
1149 }
1150 
1151 void tipc_node_check_dest(struct net *net, u32 addr,
1152 			  u8 *peer_id, struct tipc_bearer *b,
1153 			  u16 capabilities, u32 signature, u32 hash_mixes,
1154 			  struct tipc_media_addr *maddr,
1155 			  bool *respond, bool *dupl_addr)
1156 {
1157 	struct tipc_node *n;
1158 	struct tipc_link *l, *snd_l;
1159 	struct tipc_link_entry *le;
1160 	bool addr_match = false;
1161 	bool sign_match = false;
1162 	bool link_up = false;
1163 	bool accept_addr = false;
1164 	bool reset = true;
1165 	char *if_name;
1166 	unsigned long intv;
1167 	u16 session;
1168 
1169 	*dupl_addr = false;
1170 	*respond = false;
1171 
1172 	n = tipc_node_create(net, addr, peer_id, capabilities, hash_mixes,
1173 			     false);
1174 	if (!n)
1175 		return;
1176 
1177 	tipc_node_write_lock(n);
1178 	if (unlikely(!n->bc_entry.link)) {
1179 		snd_l = tipc_bc_sndlink(net);
1180 		if (!tipc_link_bc_create(net, tipc_own_addr(net),
1181 					 addr, peer_id, U16_MAX,
1182 					 tipc_link_min_win(snd_l),
1183 					 tipc_link_max_win(snd_l),
1184 					 n->capabilities,
1185 					 &n->bc_entry.inputq1,
1186 					 &n->bc_entry.namedq, snd_l,
1187 					 &n->bc_entry.link)) {
1188 			pr_warn("Broadcast rcv link creation failed, no mem\n");
1189 			tipc_node_write_unlock_fast(n);
1190 			tipc_node_put(n);
1191 			return;
1192 		}
1193 	}
1194 
1195 	le = &n->links[b->identity];
1196 
1197 	/* Prepare to validate requesting node's signature and media address */
1198 	l = le->link;
1199 	link_up = l && tipc_link_is_up(l);
1200 	addr_match = l && !memcmp(&le->maddr, maddr, sizeof(*maddr));
1201 	sign_match = (signature == n->signature);
1202 
1203 	/* These three flags give us eight permutations: */
1204 
1205 	if (sign_match && addr_match && link_up) {
1206 		/* All is fine. Do nothing. */
1207 		reset = false;
1208 		/* Peer node is not a container/local namespace */
1209 		if (!n->peer_hash_mix)
1210 			n->peer_hash_mix = hash_mixes;
1211 	} else if (sign_match && addr_match && !link_up) {
1212 		/* Respond. The link will come up in due time */
1213 		*respond = true;
1214 	} else if (sign_match && !addr_match && link_up) {
1215 		/* Peer has changed i/f address without rebooting.
1216 		 * If so, the link will reset soon, and the next
1217 		 * discovery will be accepted. So we can ignore it.
1218 		 * It may also be a cloned or malicious peer having
1219 		 * chosen the same node address and signature as an
1220 		 * existing one.
1221 		 * Ignore requests until the link goes down, if ever.
1222 		 */
1223 		*dupl_addr = true;
1224 	} else if (sign_match && !addr_match && !link_up) {
1225 		/* Peer link has changed i/f address without rebooting.
1226 		 * It may also be a cloned or malicious peer; we can't
1227 		 * distinguish between the two.
1228 		 * The signature is correct, so we must accept.
1229 		 */
1230 		accept_addr = true;
1231 		*respond = true;
1232 	} else if (!sign_match && addr_match && link_up) {
1233 		/* Peer node rebooted. Two possibilities:
1234 		 *  - Delayed re-discovery; this link endpoint has already
1235 		 *    reset and re-established contact with the peer, before
1236 		 *    receiving a discovery message from that node.
1237 		 *    (The peer happened to receive one from this node first).
1238 		 *  - The peer came back so fast that our side has not
1239 		 *    discovered it yet. Probing from this side will soon
1240 		 *    reset the link, since there can be no working link
1241 		 *    endpoint at the peer end, and the link will re-establish.
1242 		 *  Accept the signature, since it comes from a known peer.
1243 		 */
1244 		n->signature = signature;
1245 	} else if (!sign_match && addr_match && !link_up) {
1246 		/*  The peer node has rebooted.
1247 		 *  Accept signature, since it is a known peer.
1248 		 */
1249 		n->signature = signature;
1250 		*respond = true;
1251 	} else if (!sign_match && !addr_match && link_up) {
1252 		/* Peer rebooted with new address, or a new/duplicate peer.
1253 		 * Ignore until the link goes down, if ever.
1254 		 */
1255 		*dupl_addr = true;
1256 	} else if (!sign_match && !addr_match && !link_up) {
1257 		/* Peer rebooted with new address, or it is a new peer.
1258 		 * Accept signature and address.
1259 		 */
1260 		n->signature = signature;
1261 		accept_addr = true;
1262 		*respond = true;
1263 	}
1264 
1265 	if (!accept_addr)
1266 		goto exit;
1267 
1268 	/* Now create new link if not already existing */
1269 	if (!l) {
1270 		if (n->link_cnt == 2)
1271 			goto exit;
1272 
1273 		if_name = strchr(b->name, ':') + 1;
1274 		get_random_bytes(&session, sizeof(u16));
1275 		if (!tipc_link_create(net, if_name, b->identity, b->tolerance,
1276 				      b->net_plane, b->mtu, b->priority,
1277 				      b->min_win, b->max_win, session,
1278 				      tipc_own_addr(net), addr, peer_id,
1279 				      n->capabilities,
1280 				      tipc_bc_sndlink(n->net), n->bc_entry.link,
1281 				      &le->inputq,
1282 				      &n->bc_entry.namedq, &l)) {
1283 			*respond = false;
1284 			goto exit;
1285 		}
1286 		trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link created!");
1287 		tipc_link_reset(l);
1288 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1289 		if (n->state == NODE_FAILINGOVER)
1290 			tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
1291 		le->link = l;
1292 		n->link_cnt++;
1293 		tipc_node_calculate_timer(n, l);
1294 		if (n->link_cnt == 1) {
1295 			intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
1296 			if (!mod_timer(&n->timer, intv))
1297 				tipc_node_get(n);
1298 		}
1299 	}
1300 	memcpy(&le->maddr, maddr, sizeof(*maddr));
1301 exit:
1302 	tipc_node_write_unlock(n);
1303 	if (reset && l && !tipc_link_is_reset(l))
1304 		tipc_node_link_down(n, b->identity, false);
1305 	tipc_node_put(n);
1306 }
1307 
1308 void tipc_node_delete_links(struct net *net, int bearer_id)
1309 {
1310 	struct tipc_net *tn = net_generic(net, tipc_net_id);
1311 	struct tipc_node *n;
1312 
1313 	rcu_read_lock();
1314 	list_for_each_entry_rcu(n, &tn->node_list, list) {
1315 		tipc_node_link_down(n, bearer_id, true);
1316 	}
1317 	rcu_read_unlock();
1318 }
1319 
1320 static void tipc_node_reset_links(struct tipc_node *n)
1321 {
1322 	int i;
1323 
1324 	pr_warn("Resetting all links to %x\n", n->addr);
1325 
1326 	trace_tipc_node_reset_links(n, true, " ");
1327 	for (i = 0; i < MAX_BEARERS; i++) {
1328 		tipc_node_link_down(n, i, false);
1329 	}
1330 }
1331 
1332 /* tipc_node_fsm_evt - node finite state machine
1333  * Determines when contact is allowed with peer node
1334  */
1335 static void tipc_node_fsm_evt(struct tipc_node *n, int evt)
1336 {
1337 	int state = n->state;
1338 
1339 	switch (state) {
1340 	case SELF_DOWN_PEER_DOWN:
1341 		switch (evt) {
1342 		case SELF_ESTABL_CONTACT_EVT:
1343 			state = SELF_UP_PEER_COMING;
1344 			break;
1345 		case PEER_ESTABL_CONTACT_EVT:
1346 			state = SELF_COMING_PEER_UP;
1347 			break;
1348 		case SELF_LOST_CONTACT_EVT:
1349 		case PEER_LOST_CONTACT_EVT:
1350 			break;
1351 		case NODE_SYNCH_END_EVT:
1352 		case NODE_SYNCH_BEGIN_EVT:
1353 		case NODE_FAILOVER_BEGIN_EVT:
1354 		case NODE_FAILOVER_END_EVT:
1355 		default:
1356 			goto illegal_evt;
1357 		}
1358 		break;
1359 	case SELF_UP_PEER_UP:
1360 		switch (evt) {
1361 		case SELF_LOST_CONTACT_EVT:
1362 			state = SELF_DOWN_PEER_LEAVING;
1363 			break;
1364 		case PEER_LOST_CONTACT_EVT:
1365 			state = SELF_LEAVING_PEER_DOWN;
1366 			break;
1367 		case NODE_SYNCH_BEGIN_EVT:
1368 			state = NODE_SYNCHING;
1369 			break;
1370 		case NODE_FAILOVER_BEGIN_EVT:
1371 			state = NODE_FAILINGOVER;
1372 			break;
1373 		case SELF_ESTABL_CONTACT_EVT:
1374 		case PEER_ESTABL_CONTACT_EVT:
1375 		case NODE_SYNCH_END_EVT:
1376 		case NODE_FAILOVER_END_EVT:
1377 			break;
1378 		default:
1379 			goto illegal_evt;
1380 		}
1381 		break;
1382 	case SELF_DOWN_PEER_LEAVING:
1383 		switch (evt) {
1384 		case PEER_LOST_CONTACT_EVT:
1385 			state = SELF_DOWN_PEER_DOWN;
1386 			break;
1387 		case SELF_ESTABL_CONTACT_EVT:
1388 		case PEER_ESTABL_CONTACT_EVT:
1389 		case SELF_LOST_CONTACT_EVT:
1390 			break;
1391 		case NODE_SYNCH_END_EVT:
1392 		case NODE_SYNCH_BEGIN_EVT:
1393 		case NODE_FAILOVER_BEGIN_EVT:
1394 		case NODE_FAILOVER_END_EVT:
1395 		default:
1396 			goto illegal_evt;
1397 		}
1398 		break;
1399 	case SELF_UP_PEER_COMING:
1400 		switch (evt) {
1401 		case PEER_ESTABL_CONTACT_EVT:
1402 			state = SELF_UP_PEER_UP;
1403 			break;
1404 		case SELF_LOST_CONTACT_EVT:
1405 			state = SELF_DOWN_PEER_DOWN;
1406 			break;
1407 		case SELF_ESTABL_CONTACT_EVT:
1408 		case PEER_LOST_CONTACT_EVT:
1409 		case NODE_SYNCH_END_EVT:
1410 		case NODE_FAILOVER_BEGIN_EVT:
1411 			break;
1412 		case NODE_SYNCH_BEGIN_EVT:
1413 		case NODE_FAILOVER_END_EVT:
1414 		default:
1415 			goto illegal_evt;
1416 		}
1417 		break;
1418 	case SELF_COMING_PEER_UP:
1419 		switch (evt) {
1420 		case SELF_ESTABL_CONTACT_EVT:
1421 			state = SELF_UP_PEER_UP;
1422 			break;
1423 		case PEER_LOST_CONTACT_EVT:
1424 			state = SELF_DOWN_PEER_DOWN;
1425 			break;
1426 		case SELF_LOST_CONTACT_EVT:
1427 		case PEER_ESTABL_CONTACT_EVT:
1428 			break;
1429 		case NODE_SYNCH_END_EVT:
1430 		case NODE_SYNCH_BEGIN_EVT:
1431 		case NODE_FAILOVER_BEGIN_EVT:
1432 		case NODE_FAILOVER_END_EVT:
1433 		default:
1434 			goto illegal_evt;
1435 		}
1436 		break;
1437 	case SELF_LEAVING_PEER_DOWN:
1438 		switch (evt) {
1439 		case SELF_LOST_CONTACT_EVT:
1440 			state = SELF_DOWN_PEER_DOWN;
1441 			break;
1442 		case SELF_ESTABL_CONTACT_EVT:
1443 		case PEER_ESTABL_CONTACT_EVT:
1444 		case PEER_LOST_CONTACT_EVT:
1445 			break;
1446 		case NODE_SYNCH_END_EVT:
1447 		case NODE_SYNCH_BEGIN_EVT:
1448 		case NODE_FAILOVER_BEGIN_EVT:
1449 		case NODE_FAILOVER_END_EVT:
1450 		default:
1451 			goto illegal_evt;
1452 		}
1453 		break;
1454 	case NODE_FAILINGOVER:
1455 		switch (evt) {
1456 		case SELF_LOST_CONTACT_EVT:
1457 			state = SELF_DOWN_PEER_LEAVING;
1458 			break;
1459 		case PEER_LOST_CONTACT_EVT:
1460 			state = SELF_LEAVING_PEER_DOWN;
1461 			break;
1462 		case NODE_FAILOVER_END_EVT:
1463 			state = SELF_UP_PEER_UP;
1464 			break;
1465 		case NODE_FAILOVER_BEGIN_EVT:
1466 		case SELF_ESTABL_CONTACT_EVT:
1467 		case PEER_ESTABL_CONTACT_EVT:
1468 			break;
1469 		case NODE_SYNCH_BEGIN_EVT:
1470 		case NODE_SYNCH_END_EVT:
1471 		default:
1472 			goto illegal_evt;
1473 		}
1474 		break;
1475 	case NODE_SYNCHING:
1476 		switch (evt) {
1477 		case SELF_LOST_CONTACT_EVT:
1478 			state = SELF_DOWN_PEER_LEAVING;
1479 			break;
1480 		case PEER_LOST_CONTACT_EVT:
1481 			state = SELF_LEAVING_PEER_DOWN;
1482 			break;
1483 		case NODE_SYNCH_END_EVT:
1484 			state = SELF_UP_PEER_UP;
1485 			break;
1486 		case NODE_FAILOVER_BEGIN_EVT:
1487 			state = NODE_FAILINGOVER;
1488 			break;
1489 		case NODE_SYNCH_BEGIN_EVT:
1490 		case SELF_ESTABL_CONTACT_EVT:
1491 		case PEER_ESTABL_CONTACT_EVT:
1492 			break;
1493 		case NODE_FAILOVER_END_EVT:
1494 		default:
1495 			goto illegal_evt;
1496 		}
1497 		break;
1498 	default:
1499 		pr_err("Unknown node fsm state %x\n", state);
1500 		break;
1501 	}
1502 	trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
1503 	n->state = state;
1504 	return;
1505 
1506 illegal_evt:
1507 	pr_err("Illegal node fsm evt %x in state %x\n", evt, state);
1508 	trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
1509 }
1510 
1511 static void node_lost_contact(struct tipc_node *n,
1512 			      struct sk_buff_head *inputq)
1513 {
1514 	struct tipc_sock_conn *conn, *safe;
1515 	struct tipc_link *l;
1516 	struct list_head *conns = &n->conn_sks;
1517 	struct sk_buff *skb;
1518 	uint i;
1519 
1520 	pr_debug("Lost contact with %x\n", n->addr);
1521 	n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
1522 	trace_tipc_node_lost_contact(n, true, " ");
1523 
1524 	/* Clean up broadcast state */
1525 	tipc_bcast_remove_peer(n->net, n->bc_entry.link);
1526 	skb_queue_purge(&n->bc_entry.namedq);
1527 
1528 	/* Abort any ongoing link failover */
1529 	for (i = 0; i < MAX_BEARERS; i++) {
1530 		l = n->links[i].link;
1531 		if (l)
1532 			tipc_link_fsm_evt(l, LINK_FAILOVER_END_EVT);
1533 	}
1534 
1535 	/* Notify publications from this node */
1536 	n->action_flags |= TIPC_NOTIFY_NODE_DOWN;
1537 	n->peer_net = NULL;
1538 	n->peer_hash_mix = 0;
1539 	/* Notify sockets connected to node */
1540 	list_for_each_entry_safe(conn, safe, conns, list) {
1541 		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_CONN_MSG,
1542 				      SHORT_H_SIZE, 0, tipc_own_addr(n->net),
1543 				      conn->peer_node, conn->port,
1544 				      conn->peer_port, TIPC_ERR_NO_NODE);
1545 		if (likely(skb))
1546 			skb_queue_tail(inputq, skb);
1547 		list_del(&conn->list);
1548 		kfree(conn);
1549 	}
1550 }
1551 
1552 /**
1553  * tipc_node_get_linkname - get the name of a link
1554  *
1555  * @net: the applicable net namespace
1556  * @bearer_id: id of the bearer
1557  * @addr: peer node address
1558  * @linkname: link name output buffer
1559  * @len: size of @linkname output buffer
1560  *
1561  * Return: 0 on success
1562  */
1563 int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 addr,
1564 			   char *linkname, size_t len)
1565 {
1566 	struct tipc_link *link;
1567 	int err = -EINVAL;
1568 	struct tipc_node *node = tipc_node_find(net, addr);
1569 
1570 	if (!node)
1571 		return err;
1572 
1573 	if (bearer_id >= MAX_BEARERS)
1574 		goto exit;
1575 
1576 	tipc_node_read_lock(node);
1577 	link = node->links[bearer_id].link;
1578 	if (link) {
1579 		strncpy(linkname, tipc_link_name(link), len);
1580 		err = 0;
1581 	}
1582 	tipc_node_read_unlock(node);
1583 exit:
1584 	tipc_node_put(node);
1585 	return err;
1586 }
1587 
1588 /* Caller should hold node lock for the passed node */
1589 static int __tipc_nl_add_node(struct tipc_nl_msg *msg, struct tipc_node *node)
1590 {
1591 	void *hdr;
1592 	struct nlattr *attrs;
1593 
1594 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1595 			  NLM_F_MULTI, TIPC_NL_NODE_GET);
1596 	if (!hdr)
1597 		return -EMSGSIZE;
1598 
1599 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NODE);
1600 	if (!attrs)
1601 		goto msg_full;
1602 
1603 	if (nla_put_u32(msg->skb, TIPC_NLA_NODE_ADDR, node->addr))
1604 		goto attr_msg_full;
1605 	if (node_is_up(node))
1606 		if (nla_put_flag(msg->skb, TIPC_NLA_NODE_UP))
1607 			goto attr_msg_full;
1608 
1609 	nla_nest_end(msg->skb, attrs);
1610 	genlmsg_end(msg->skb, hdr);
1611 
1612 	return 0;
1613 
1614 attr_msg_full:
1615 	nla_nest_cancel(msg->skb, attrs);
1616 msg_full:
1617 	genlmsg_cancel(msg->skb, hdr);
1618 
1619 	return -EMSGSIZE;
1620 }
1621 
1622 static void tipc_lxc_xmit(struct net *peer_net, struct sk_buff_head *list)
1623 {
1624 	struct tipc_msg *hdr = buf_msg(skb_peek(list));
1625 	struct sk_buff_head inputq;
1626 
1627 	switch (msg_user(hdr)) {
1628 	case TIPC_LOW_IMPORTANCE:
1629 	case TIPC_MEDIUM_IMPORTANCE:
1630 	case TIPC_HIGH_IMPORTANCE:
1631 	case TIPC_CRITICAL_IMPORTANCE:
1632 		if (msg_connected(hdr) || msg_named(hdr) ||
1633 		    msg_direct(hdr)) {
1634 			tipc_loopback_trace(peer_net, list);
1635 			spin_lock_init(&list->lock);
1636 			tipc_sk_rcv(peer_net, list);
1637 			return;
1638 		}
1639 		if (msg_mcast(hdr)) {
1640 			tipc_loopback_trace(peer_net, list);
1641 			skb_queue_head_init(&inputq);
1642 			tipc_sk_mcast_rcv(peer_net, list, &inputq);
1643 			__skb_queue_purge(list);
1644 			skb_queue_purge(&inputq);
1645 			return;
1646 		}
1647 		return;
1648 	case MSG_FRAGMENTER:
1649 		if (tipc_msg_assemble(list)) {
1650 			tipc_loopback_trace(peer_net, list);
1651 			skb_queue_head_init(&inputq);
1652 			tipc_sk_mcast_rcv(peer_net, list, &inputq);
1653 			__skb_queue_purge(list);
1654 			skb_queue_purge(&inputq);
1655 		}
1656 		return;
1657 	case GROUP_PROTOCOL:
1658 	case CONN_MANAGER:
1659 		tipc_loopback_trace(peer_net, list);
1660 		spin_lock_init(&list->lock);
1661 		tipc_sk_rcv(peer_net, list);
1662 		return;
1663 	case LINK_PROTOCOL:
1664 	case NAME_DISTRIBUTOR:
1665 	case TUNNEL_PROTOCOL:
1666 	case BCAST_PROTOCOL:
1667 		return;
1668 	default:
1669 		return;
1670 	}
1671 }
1672 
1673 /**
1674  * tipc_node_xmit() - general link level function for message sending
1675  * @net: the applicable net namespace
1676  * @list: chain of buffers containing message
1677  * @dnode: address of destination node
1678  * @selector: a number used for deterministic link selection
1679  * Consumes the buffer chain.
1680  * Return: 0 if success, otherwise: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE,-ENOBUF
1681  */
1682 int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
1683 		   u32 dnode, int selector)
1684 {
1685 	struct tipc_link_entry *le = NULL;
1686 	struct tipc_node *n;
1687 	struct sk_buff_head xmitq;
1688 	bool node_up = false;
1689 	int bearer_id;
1690 	int rc;
1691 
1692 	if (in_own_node(net, dnode)) {
1693 		tipc_loopback_trace(net, list);
1694 		spin_lock_init(&list->lock);
1695 		tipc_sk_rcv(net, list);
1696 		return 0;
1697 	}
1698 
1699 	n = tipc_node_find(net, dnode);
1700 	if (unlikely(!n)) {
1701 		__skb_queue_purge(list);
1702 		return -EHOSTUNREACH;
1703 	}
1704 
1705 	tipc_node_read_lock(n);
1706 	node_up = node_is_up(n);
1707 	if (node_up && n->peer_net && check_net(n->peer_net)) {
1708 		/* xmit inner linux container */
1709 		tipc_lxc_xmit(n->peer_net, list);
1710 		if (likely(skb_queue_empty(list))) {
1711 			tipc_node_read_unlock(n);
1712 			tipc_node_put(n);
1713 			return 0;
1714 		}
1715 	}
1716 
1717 	bearer_id = n->active_links[selector & 1];
1718 	if (unlikely(bearer_id == INVALID_BEARER_ID)) {
1719 		tipc_node_read_unlock(n);
1720 		tipc_node_put(n);
1721 		__skb_queue_purge(list);
1722 		return -EHOSTUNREACH;
1723 	}
1724 
1725 	__skb_queue_head_init(&xmitq);
1726 	le = &n->links[bearer_id];
1727 	spin_lock_bh(&le->lock);
1728 	rc = tipc_link_xmit(le->link, list, &xmitq);
1729 	spin_unlock_bh(&le->lock);
1730 	tipc_node_read_unlock(n);
1731 
1732 	if (unlikely(rc == -ENOBUFS))
1733 		tipc_node_link_down(n, bearer_id, false);
1734 	else
1735 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
1736 
1737 	tipc_node_put(n);
1738 
1739 	return rc;
1740 }
1741 
1742 /* tipc_node_xmit_skb(): send single buffer to destination
1743  * Buffers sent via this function are generally TIPC_SYSTEM_IMPORTANCE
1744  * messages, which will not be rejected
1745  * The only exception is datagram messages rerouted after secondary
1746  * lookup, which are rare and safe to dispose of anyway.
1747  */
1748 int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode,
1749 		       u32 selector)
1750 {
1751 	struct sk_buff_head head;
1752 
1753 	__skb_queue_head_init(&head);
1754 	__skb_queue_tail(&head, skb);
1755 	tipc_node_xmit(net, &head, dnode, selector);
1756 	return 0;
1757 }
1758 
1759 /* tipc_node_distr_xmit(): send single buffer msgs to individual destinations
1760  * Note: this is only for SYSTEM_IMPORTANCE messages, which cannot be rejected
1761  */
1762 int tipc_node_distr_xmit(struct net *net, struct sk_buff_head *xmitq)
1763 {
1764 	struct sk_buff *skb;
1765 	u32 selector, dnode;
1766 
1767 	while ((skb = __skb_dequeue(xmitq))) {
1768 		selector = msg_origport(buf_msg(skb));
1769 		dnode = msg_destnode(buf_msg(skb));
1770 		tipc_node_xmit_skb(net, skb, dnode, selector);
1771 	}
1772 	return 0;
1773 }
1774 
1775 void tipc_node_broadcast(struct net *net, struct sk_buff *skb, int rc_dests)
1776 {
1777 	struct sk_buff_head xmitq;
1778 	struct sk_buff *txskb;
1779 	struct tipc_node *n;
1780 	u16 dummy;
1781 	u32 dst;
1782 
1783 	/* Use broadcast if all nodes support it */
1784 	if (!rc_dests && tipc_bcast_get_mode(net) != BCLINK_MODE_RCAST) {
1785 		__skb_queue_head_init(&xmitq);
1786 		__skb_queue_tail(&xmitq, skb);
1787 		tipc_bcast_xmit(net, &xmitq, &dummy);
1788 		return;
1789 	}
1790 
1791 	/* Otherwise use legacy replicast method */
1792 	rcu_read_lock();
1793 	list_for_each_entry_rcu(n, tipc_nodes(net), list) {
1794 		dst = n->addr;
1795 		if (in_own_node(net, dst))
1796 			continue;
1797 		if (!node_is_up(n))
1798 			continue;
1799 		txskb = pskb_copy(skb, GFP_ATOMIC);
1800 		if (!txskb)
1801 			break;
1802 		msg_set_destnode(buf_msg(txskb), dst);
1803 		tipc_node_xmit_skb(net, txskb, dst, 0);
1804 	}
1805 	rcu_read_unlock();
1806 	kfree_skb(skb);
1807 }
1808 
1809 static void tipc_node_mcast_rcv(struct tipc_node *n)
1810 {
1811 	struct tipc_bclink_entry *be = &n->bc_entry;
1812 
1813 	/* 'arrvq' is under inputq2's lock protection */
1814 	spin_lock_bh(&be->inputq2.lock);
1815 	spin_lock_bh(&be->inputq1.lock);
1816 	skb_queue_splice_tail_init(&be->inputq1, &be->arrvq);
1817 	spin_unlock_bh(&be->inputq1.lock);
1818 	spin_unlock_bh(&be->inputq2.lock);
1819 	tipc_sk_mcast_rcv(n->net, &be->arrvq, &be->inputq2);
1820 }
1821 
1822 static void tipc_node_bc_sync_rcv(struct tipc_node *n, struct tipc_msg *hdr,
1823 				  int bearer_id, struct sk_buff_head *xmitq)
1824 {
1825 	struct tipc_link *ucl;
1826 	int rc;
1827 
1828 	rc = tipc_bcast_sync_rcv(n->net, n->bc_entry.link, hdr, xmitq);
1829 
1830 	if (rc & TIPC_LINK_DOWN_EVT) {
1831 		tipc_node_reset_links(n);
1832 		return;
1833 	}
1834 
1835 	if (!(rc & TIPC_LINK_SND_STATE))
1836 		return;
1837 
1838 	/* If probe message, a STATE response will be sent anyway */
1839 	if (msg_probe(hdr))
1840 		return;
1841 
1842 	/* Produce a STATE message carrying broadcast NACK */
1843 	tipc_node_read_lock(n);
1844 	ucl = n->links[bearer_id].link;
1845 	if (ucl)
1846 		tipc_link_build_state_msg(ucl, xmitq);
1847 	tipc_node_read_unlock(n);
1848 }
1849 
1850 /**
1851  * tipc_node_bc_rcv - process TIPC broadcast packet arriving from off-node
1852  * @net: the applicable net namespace
1853  * @skb: TIPC packet
1854  * @bearer_id: id of bearer message arrived on
1855  *
1856  * Invoked with no locks held.
1857  */
1858 static void tipc_node_bc_rcv(struct net *net, struct sk_buff *skb, int bearer_id)
1859 {
1860 	int rc;
1861 	struct sk_buff_head xmitq;
1862 	struct tipc_bclink_entry *be;
1863 	struct tipc_link_entry *le;
1864 	struct tipc_msg *hdr = buf_msg(skb);
1865 	int usr = msg_user(hdr);
1866 	u32 dnode = msg_destnode(hdr);
1867 	struct tipc_node *n;
1868 
1869 	__skb_queue_head_init(&xmitq);
1870 
1871 	/* If NACK for other node, let rcv link for that node peek into it */
1872 	if ((usr == BCAST_PROTOCOL) && (dnode != tipc_own_addr(net)))
1873 		n = tipc_node_find(net, dnode);
1874 	else
1875 		n = tipc_node_find(net, msg_prevnode(hdr));
1876 	if (!n) {
1877 		kfree_skb(skb);
1878 		return;
1879 	}
1880 	be = &n->bc_entry;
1881 	le = &n->links[bearer_id];
1882 
1883 	rc = tipc_bcast_rcv(net, be->link, skb);
1884 
1885 	/* Broadcast ACKs are sent on a unicast link */
1886 	if (rc & TIPC_LINK_SND_STATE) {
1887 		tipc_node_read_lock(n);
1888 		tipc_link_build_state_msg(le->link, &xmitq);
1889 		tipc_node_read_unlock(n);
1890 	}
1891 
1892 	if (!skb_queue_empty(&xmitq))
1893 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
1894 
1895 	if (!skb_queue_empty(&be->inputq1))
1896 		tipc_node_mcast_rcv(n);
1897 
1898 	/* Handle NAME_DISTRIBUTOR messages sent from 1.7 nodes */
1899 	if (!skb_queue_empty(&n->bc_entry.namedq))
1900 		tipc_named_rcv(net, &n->bc_entry.namedq,
1901 			       &n->bc_entry.named_rcv_nxt,
1902 			       &n->bc_entry.named_open);
1903 
1904 	/* If reassembly or retransmission failure => reset all links to peer */
1905 	if (rc & TIPC_LINK_DOWN_EVT)
1906 		tipc_node_reset_links(n);
1907 
1908 	tipc_node_put(n);
1909 }
1910 
1911 /**
1912  * tipc_node_check_state - check and if necessary update node state
1913  * @n: target tipc_node
1914  * @skb: TIPC packet
1915  * @bearer_id: identity of bearer delivering the packet
1916  * @xmitq: queue for messages to be xmited on
1917  * Return: true if state and msg are ok, otherwise false
1918  */
1919 static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
1920 				  int bearer_id, struct sk_buff_head *xmitq)
1921 {
1922 	struct tipc_msg *hdr = buf_msg(skb);
1923 	int usr = msg_user(hdr);
1924 	int mtyp = msg_type(hdr);
1925 	u16 oseqno = msg_seqno(hdr);
1926 	u16 exp_pkts = msg_msgcnt(hdr);
1927 	u16 rcv_nxt, syncpt, dlv_nxt, inputq_len;
1928 	int state = n->state;
1929 	struct tipc_link *l, *tnl, *pl = NULL;
1930 	struct tipc_media_addr *maddr;
1931 	int pb_id;
1932 
1933 	if (trace_tipc_node_check_state_enabled()) {
1934 		trace_tipc_skb_dump(skb, false, "skb for node state check");
1935 		trace_tipc_node_check_state(n, true, " ");
1936 	}
1937 	l = n->links[bearer_id].link;
1938 	if (!l)
1939 		return false;
1940 	rcv_nxt = tipc_link_rcv_nxt(l);
1941 
1942 
1943 	if (likely((state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL)))
1944 		return true;
1945 
1946 	/* Find parallel link, if any */
1947 	for (pb_id = 0; pb_id < MAX_BEARERS; pb_id++) {
1948 		if ((pb_id != bearer_id) && n->links[pb_id].link) {
1949 			pl = n->links[pb_id].link;
1950 			break;
1951 		}
1952 	}
1953 
1954 	if (!tipc_link_validate_msg(l, hdr)) {
1955 		trace_tipc_skb_dump(skb, false, "PROTO invalid (2)!");
1956 		trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (2)!");
1957 		return false;
1958 	}
1959 
1960 	/* Check and update node accesibility if applicable */
1961 	if (state == SELF_UP_PEER_COMING) {
1962 		if (!tipc_link_is_up(l))
1963 			return true;
1964 		if (!msg_peer_link_is_up(hdr))
1965 			return true;
1966 		tipc_node_fsm_evt(n, PEER_ESTABL_CONTACT_EVT);
1967 	}
1968 
1969 	if (state == SELF_DOWN_PEER_LEAVING) {
1970 		if (msg_peer_node_is_up(hdr))
1971 			return false;
1972 		tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
1973 		return true;
1974 	}
1975 
1976 	if (state == SELF_LEAVING_PEER_DOWN)
1977 		return false;
1978 
1979 	/* Ignore duplicate packets */
1980 	if ((usr != LINK_PROTOCOL) && less(oseqno, rcv_nxt))
1981 		return true;
1982 
1983 	/* Initiate or update failover mode if applicable */
1984 	if ((usr == TUNNEL_PROTOCOL) && (mtyp == FAILOVER_MSG)) {
1985 		syncpt = oseqno + exp_pkts - 1;
1986 		if (pl && !tipc_link_is_reset(pl)) {
1987 			__tipc_node_link_down(n, &pb_id, xmitq, &maddr);
1988 			trace_tipc_node_link_down(n, true,
1989 						  "node link down <- failover!");
1990 			tipc_skb_queue_splice_tail_init(tipc_link_inputq(pl),
1991 							tipc_link_inputq(l));
1992 		}
1993 
1994 		/* If parallel link was already down, and this happened before
1995 		 * the tunnel link came up, node failover was never started.
1996 		 * Ensure that a FAILOVER_MSG is sent to get peer out of
1997 		 * NODE_FAILINGOVER state, also this node must accept
1998 		 * TUNNEL_MSGs from peer.
1999 		 */
2000 		if (n->state != NODE_FAILINGOVER)
2001 			tipc_node_link_failover(n, pl, l, xmitq);
2002 
2003 		/* If pkts arrive out of order, use lowest calculated syncpt */
2004 		if (less(syncpt, n->sync_point))
2005 			n->sync_point = syncpt;
2006 	}
2007 
2008 	/* Open parallel link when tunnel link reaches synch point */
2009 	if ((n->state == NODE_FAILINGOVER) && tipc_link_is_up(l)) {
2010 		if (!more(rcv_nxt, n->sync_point))
2011 			return true;
2012 		tipc_node_fsm_evt(n, NODE_FAILOVER_END_EVT);
2013 		if (pl)
2014 			tipc_link_fsm_evt(pl, LINK_FAILOVER_END_EVT);
2015 		return true;
2016 	}
2017 
2018 	/* No syncing needed if only one link */
2019 	if (!pl || !tipc_link_is_up(pl))
2020 		return true;
2021 
2022 	/* Initiate synch mode if applicable */
2023 	if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG) && (oseqno == 1)) {
2024 		if (n->capabilities & TIPC_TUNNEL_ENHANCED)
2025 			syncpt = msg_syncpt(hdr);
2026 		else
2027 			syncpt = msg_seqno(msg_inner_hdr(hdr)) + exp_pkts - 1;
2028 		if (!tipc_link_is_up(l))
2029 			__tipc_node_link_up(n, bearer_id, xmitq);
2030 		if (n->state == SELF_UP_PEER_UP) {
2031 			n->sync_point = syncpt;
2032 			tipc_link_fsm_evt(l, LINK_SYNCH_BEGIN_EVT);
2033 			tipc_node_fsm_evt(n, NODE_SYNCH_BEGIN_EVT);
2034 		}
2035 	}
2036 
2037 	/* Open tunnel link when parallel link reaches synch point */
2038 	if (n->state == NODE_SYNCHING) {
2039 		if (tipc_link_is_synching(l)) {
2040 			tnl = l;
2041 		} else {
2042 			tnl = pl;
2043 			pl = l;
2044 		}
2045 		inputq_len = skb_queue_len(tipc_link_inputq(pl));
2046 		dlv_nxt = tipc_link_rcv_nxt(pl) - inputq_len;
2047 		if (more(dlv_nxt, n->sync_point)) {
2048 			tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
2049 			tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
2050 			return true;
2051 		}
2052 		if (l == pl)
2053 			return true;
2054 		if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG))
2055 			return true;
2056 		if (usr == LINK_PROTOCOL)
2057 			return true;
2058 		return false;
2059 	}
2060 	return true;
2061 }
2062 
2063 /**
2064  * tipc_rcv - process TIPC packets/messages arriving from off-node
2065  * @net: the applicable net namespace
2066  * @skb: TIPC packet
2067  * @b: pointer to bearer message arrived on
2068  *
2069  * Invoked with no locks held. Bearer pointer must point to a valid bearer
2070  * structure (i.e. cannot be NULL), but bearer can be inactive.
2071  */
2072 void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
2073 {
2074 	struct sk_buff_head xmitq;
2075 	struct tipc_link_entry *le;
2076 	struct tipc_msg *hdr;
2077 	struct tipc_node *n;
2078 	int bearer_id = b->identity;
2079 	u32 self = tipc_own_addr(net);
2080 	int usr, rc = 0;
2081 	u16 bc_ack;
2082 #ifdef CONFIG_TIPC_CRYPTO
2083 	struct tipc_ehdr *ehdr;
2084 
2085 	/* Check if message must be decrypted first */
2086 	if (TIPC_SKB_CB(skb)->decrypted || !tipc_ehdr_validate(skb))
2087 		goto rcv;
2088 
2089 	ehdr = (struct tipc_ehdr *)skb->data;
2090 	if (likely(ehdr->user != LINK_CONFIG)) {
2091 		n = tipc_node_find(net, ntohl(ehdr->addr));
2092 		if (unlikely(!n))
2093 			goto discard;
2094 	} else {
2095 		n = tipc_node_find_by_id(net, ehdr->id);
2096 	}
2097 	tipc_crypto_rcv(net, (n) ? n->crypto_rx : NULL, &skb, b);
2098 	if (!skb)
2099 		return;
2100 
2101 rcv:
2102 #endif
2103 	/* Ensure message is well-formed before touching the header */
2104 	if (unlikely(!tipc_msg_validate(&skb)))
2105 		goto discard;
2106 	__skb_queue_head_init(&xmitq);
2107 	hdr = buf_msg(skb);
2108 	usr = msg_user(hdr);
2109 	bc_ack = msg_bcast_ack(hdr);
2110 
2111 	/* Handle arrival of discovery or broadcast packet */
2112 	if (unlikely(msg_non_seq(hdr))) {
2113 		if (unlikely(usr == LINK_CONFIG))
2114 			return tipc_disc_rcv(net, skb, b);
2115 		else
2116 			return tipc_node_bc_rcv(net, skb, bearer_id);
2117 	}
2118 
2119 	/* Discard unicast link messages destined for another node */
2120 	if (unlikely(!msg_short(hdr) && (msg_destnode(hdr) != self)))
2121 		goto discard;
2122 
2123 	/* Locate neighboring node that sent packet */
2124 	n = tipc_node_find(net, msg_prevnode(hdr));
2125 	if (unlikely(!n))
2126 		goto discard;
2127 	le = &n->links[bearer_id];
2128 
2129 	/* Ensure broadcast reception is in synch with peer's send state */
2130 	if (unlikely(usr == LINK_PROTOCOL)) {
2131 		if (unlikely(skb_linearize(skb))) {
2132 			tipc_node_put(n);
2133 			goto discard;
2134 		}
2135 		hdr = buf_msg(skb);
2136 		tipc_node_bc_sync_rcv(n, hdr, bearer_id, &xmitq);
2137 	} else if (unlikely(tipc_link_acked(n->bc_entry.link) != bc_ack)) {
2138 		tipc_bcast_ack_rcv(net, n->bc_entry.link, hdr);
2139 	}
2140 
2141 	/* Receive packet directly if conditions permit */
2142 	tipc_node_read_lock(n);
2143 	if (likely((n->state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL))) {
2144 		spin_lock_bh(&le->lock);
2145 		if (le->link) {
2146 			rc = tipc_link_rcv(le->link, skb, &xmitq);
2147 			skb = NULL;
2148 		}
2149 		spin_unlock_bh(&le->lock);
2150 	}
2151 	tipc_node_read_unlock(n);
2152 
2153 	/* Check/update node state before receiving */
2154 	if (unlikely(skb)) {
2155 		if (unlikely(skb_linearize(skb)))
2156 			goto out_node_put;
2157 		tipc_node_write_lock(n);
2158 		if (tipc_node_check_state(n, skb, bearer_id, &xmitq)) {
2159 			if (le->link) {
2160 				rc = tipc_link_rcv(le->link, skb, &xmitq);
2161 				skb = NULL;
2162 			}
2163 		}
2164 		tipc_node_write_unlock(n);
2165 	}
2166 
2167 	if (unlikely(rc & TIPC_LINK_UP_EVT))
2168 		tipc_node_link_up(n, bearer_id, &xmitq);
2169 
2170 	if (unlikely(rc & TIPC_LINK_DOWN_EVT))
2171 		tipc_node_link_down(n, bearer_id, false);
2172 
2173 	if (unlikely(!skb_queue_empty(&n->bc_entry.namedq)))
2174 		tipc_named_rcv(net, &n->bc_entry.namedq,
2175 			       &n->bc_entry.named_rcv_nxt,
2176 			       &n->bc_entry.named_open);
2177 
2178 	if (unlikely(!skb_queue_empty(&n->bc_entry.inputq1)))
2179 		tipc_node_mcast_rcv(n);
2180 
2181 	if (!skb_queue_empty(&le->inputq))
2182 		tipc_sk_rcv(net, &le->inputq);
2183 
2184 	if (!skb_queue_empty(&xmitq))
2185 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
2186 
2187 out_node_put:
2188 	tipc_node_put(n);
2189 discard:
2190 	kfree_skb(skb);
2191 }
2192 
2193 void tipc_node_apply_property(struct net *net, struct tipc_bearer *b,
2194 			      int prop)
2195 {
2196 	struct tipc_net *tn = tipc_net(net);
2197 	int bearer_id = b->identity;
2198 	struct sk_buff_head xmitq;
2199 	struct tipc_link_entry *e;
2200 	struct tipc_node *n;
2201 
2202 	__skb_queue_head_init(&xmitq);
2203 
2204 	rcu_read_lock();
2205 
2206 	list_for_each_entry_rcu(n, &tn->node_list, list) {
2207 		tipc_node_write_lock(n);
2208 		e = &n->links[bearer_id];
2209 		if (e->link) {
2210 			if (prop == TIPC_NLA_PROP_TOL)
2211 				tipc_link_set_tolerance(e->link, b->tolerance,
2212 							&xmitq);
2213 			else if (prop == TIPC_NLA_PROP_MTU)
2214 				tipc_link_set_mtu(e->link, b->mtu);
2215 
2216 			/* Update MTU for node link entry */
2217 			e->mtu = tipc_link_mss(e->link);
2218 		}
2219 
2220 		tipc_node_write_unlock(n);
2221 		tipc_bearer_xmit(net, bearer_id, &xmitq, &e->maddr, NULL);
2222 	}
2223 
2224 	rcu_read_unlock();
2225 }
2226 
2227 int tipc_nl_peer_rm(struct sk_buff *skb, struct genl_info *info)
2228 {
2229 	struct net *net = sock_net(skb->sk);
2230 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2231 	struct nlattr *attrs[TIPC_NLA_NET_MAX + 1];
2232 	struct tipc_node *peer, *temp_node;
2233 	u8 node_id[NODE_ID_LEN];
2234 	u64 *w0 = (u64 *)&node_id[0];
2235 	u64 *w1 = (u64 *)&node_id[8];
2236 	u32 addr;
2237 	int err;
2238 
2239 	/* We identify the peer by its net */
2240 	if (!info->attrs[TIPC_NLA_NET])
2241 		return -EINVAL;
2242 
2243 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_NET_MAX,
2244 					  info->attrs[TIPC_NLA_NET],
2245 					  tipc_nl_net_policy, info->extack);
2246 	if (err)
2247 		return err;
2248 
2249 	/* attrs[TIPC_NLA_NET_NODEID] and attrs[TIPC_NLA_NET_ADDR] are
2250 	 * mutually exclusive cases
2251 	 */
2252 	if (attrs[TIPC_NLA_NET_ADDR]) {
2253 		addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]);
2254 		if (!addr)
2255 			return -EINVAL;
2256 	}
2257 
2258 	if (attrs[TIPC_NLA_NET_NODEID]) {
2259 		if (!attrs[TIPC_NLA_NET_NODEID_W1])
2260 			return -EINVAL;
2261 		*w0 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID]);
2262 		*w1 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID_W1]);
2263 		addr = hash128to32(node_id);
2264 	}
2265 
2266 	if (in_own_node(net, addr))
2267 		return -ENOTSUPP;
2268 
2269 	spin_lock_bh(&tn->node_list_lock);
2270 	peer = tipc_node_find(net, addr);
2271 	if (!peer) {
2272 		spin_unlock_bh(&tn->node_list_lock);
2273 		return -ENXIO;
2274 	}
2275 
2276 	tipc_node_write_lock(peer);
2277 	if (peer->state != SELF_DOWN_PEER_DOWN &&
2278 	    peer->state != SELF_DOWN_PEER_LEAVING) {
2279 		tipc_node_write_unlock(peer);
2280 		err = -EBUSY;
2281 		goto err_out;
2282 	}
2283 
2284 	tipc_node_clear_links(peer);
2285 	tipc_node_write_unlock(peer);
2286 	tipc_node_delete(peer);
2287 
2288 	/* Calculate cluster capabilities */
2289 	tn->capabilities = TIPC_NODE_CAPABILITIES;
2290 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
2291 		tn->capabilities &= temp_node->capabilities;
2292 	}
2293 	tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
2294 	err = 0;
2295 err_out:
2296 	tipc_node_put(peer);
2297 	spin_unlock_bh(&tn->node_list_lock);
2298 
2299 	return err;
2300 }
2301 
2302 int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb)
2303 {
2304 	int err;
2305 	struct net *net = sock_net(skb->sk);
2306 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2307 	int done = cb->args[0];
2308 	int last_addr = cb->args[1];
2309 	struct tipc_node *node;
2310 	struct tipc_nl_msg msg;
2311 
2312 	if (done)
2313 		return 0;
2314 
2315 	msg.skb = skb;
2316 	msg.portid = NETLINK_CB(cb->skb).portid;
2317 	msg.seq = cb->nlh->nlmsg_seq;
2318 
2319 	rcu_read_lock();
2320 	if (last_addr) {
2321 		node = tipc_node_find(net, last_addr);
2322 		if (!node) {
2323 			rcu_read_unlock();
2324 			/* We never set seq or call nl_dump_check_consistent()
2325 			 * this means that setting prev_seq here will cause the
2326 			 * consistence check to fail in the netlink callback
2327 			 * handler. Resulting in the NLMSG_DONE message having
2328 			 * the NLM_F_DUMP_INTR flag set if the node state
2329 			 * changed while we released the lock.
2330 			 */
2331 			cb->prev_seq = 1;
2332 			return -EPIPE;
2333 		}
2334 		tipc_node_put(node);
2335 	}
2336 
2337 	list_for_each_entry_rcu(node, &tn->node_list, list) {
2338 		if (node->preliminary)
2339 			continue;
2340 		if (last_addr) {
2341 			if (node->addr == last_addr)
2342 				last_addr = 0;
2343 			else
2344 				continue;
2345 		}
2346 
2347 		tipc_node_read_lock(node);
2348 		err = __tipc_nl_add_node(&msg, node);
2349 		if (err) {
2350 			last_addr = node->addr;
2351 			tipc_node_read_unlock(node);
2352 			goto out;
2353 		}
2354 
2355 		tipc_node_read_unlock(node);
2356 	}
2357 	done = 1;
2358 out:
2359 	cb->args[0] = done;
2360 	cb->args[1] = last_addr;
2361 	rcu_read_unlock();
2362 
2363 	return skb->len;
2364 }
2365 
2366 /* tipc_node_find_by_name - locate owner node of link by link's name
2367  * @net: the applicable net namespace
2368  * @name: pointer to link name string
2369  * @bearer_id: pointer to index in 'node->links' array where the link was found.
2370  *
2371  * Returns pointer to node owning the link, or 0 if no matching link is found.
2372  */
2373 static struct tipc_node *tipc_node_find_by_name(struct net *net,
2374 						const char *link_name,
2375 						unsigned int *bearer_id)
2376 {
2377 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2378 	struct tipc_link *l;
2379 	struct tipc_node *n;
2380 	struct tipc_node *found_node = NULL;
2381 	int i;
2382 
2383 	*bearer_id = 0;
2384 	rcu_read_lock();
2385 	list_for_each_entry_rcu(n, &tn->node_list, list) {
2386 		tipc_node_read_lock(n);
2387 		for (i = 0; i < MAX_BEARERS; i++) {
2388 			l = n->links[i].link;
2389 			if (l && !strcmp(tipc_link_name(l), link_name)) {
2390 				*bearer_id = i;
2391 				found_node = n;
2392 				break;
2393 			}
2394 		}
2395 		tipc_node_read_unlock(n);
2396 		if (found_node)
2397 			break;
2398 	}
2399 	rcu_read_unlock();
2400 
2401 	return found_node;
2402 }
2403 
2404 int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info)
2405 {
2406 	int err;
2407 	int res = 0;
2408 	int bearer_id;
2409 	char *name;
2410 	struct tipc_link *link;
2411 	struct tipc_node *node;
2412 	struct sk_buff_head xmitq;
2413 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2414 	struct net *net = sock_net(skb->sk);
2415 
2416 	__skb_queue_head_init(&xmitq);
2417 
2418 	if (!info->attrs[TIPC_NLA_LINK])
2419 		return -EINVAL;
2420 
2421 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2422 					  info->attrs[TIPC_NLA_LINK],
2423 					  tipc_nl_link_policy, info->extack);
2424 	if (err)
2425 		return err;
2426 
2427 	if (!attrs[TIPC_NLA_LINK_NAME])
2428 		return -EINVAL;
2429 
2430 	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2431 
2432 	if (strcmp(name, tipc_bclink_name) == 0)
2433 		return tipc_nl_bc_link_set(net, attrs);
2434 
2435 	node = tipc_node_find_by_name(net, name, &bearer_id);
2436 	if (!node)
2437 		return -EINVAL;
2438 
2439 	tipc_node_read_lock(node);
2440 
2441 	link = node->links[bearer_id].link;
2442 	if (!link) {
2443 		res = -EINVAL;
2444 		goto out;
2445 	}
2446 
2447 	if (attrs[TIPC_NLA_LINK_PROP]) {
2448 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
2449 
2450 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP], props);
2451 		if (err) {
2452 			res = err;
2453 			goto out;
2454 		}
2455 
2456 		if (props[TIPC_NLA_PROP_TOL]) {
2457 			u32 tol;
2458 
2459 			tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2460 			tipc_link_set_tolerance(link, tol, &xmitq);
2461 		}
2462 		if (props[TIPC_NLA_PROP_PRIO]) {
2463 			u32 prio;
2464 
2465 			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2466 			tipc_link_set_prio(link, prio, &xmitq);
2467 		}
2468 		if (props[TIPC_NLA_PROP_WIN]) {
2469 			u32 max_win;
2470 
2471 			max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2472 			tipc_link_set_queue_limits(link,
2473 						   tipc_link_min_win(link),
2474 						   max_win);
2475 		}
2476 	}
2477 
2478 out:
2479 	tipc_node_read_unlock(node);
2480 	tipc_bearer_xmit(net, bearer_id, &xmitq, &node->links[bearer_id].maddr,
2481 			 NULL);
2482 	return res;
2483 }
2484 
2485 int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info)
2486 {
2487 	struct net *net = genl_info_net(info);
2488 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2489 	struct tipc_nl_msg msg;
2490 	char *name;
2491 	int err;
2492 
2493 	msg.portid = info->snd_portid;
2494 	msg.seq = info->snd_seq;
2495 
2496 	if (!info->attrs[TIPC_NLA_LINK])
2497 		return -EINVAL;
2498 
2499 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2500 					  info->attrs[TIPC_NLA_LINK],
2501 					  tipc_nl_link_policy, info->extack);
2502 	if (err)
2503 		return err;
2504 
2505 	if (!attrs[TIPC_NLA_LINK_NAME])
2506 		return -EINVAL;
2507 
2508 	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2509 
2510 	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2511 	if (!msg.skb)
2512 		return -ENOMEM;
2513 
2514 	if (strcmp(name, tipc_bclink_name) == 0) {
2515 		err = tipc_nl_add_bc_link(net, &msg, tipc_net(net)->bcl);
2516 		if (err)
2517 			goto err_free;
2518 	} else {
2519 		int bearer_id;
2520 		struct tipc_node *node;
2521 		struct tipc_link *link;
2522 
2523 		node = tipc_node_find_by_name(net, name, &bearer_id);
2524 		if (!node) {
2525 			err = -EINVAL;
2526 			goto err_free;
2527 		}
2528 
2529 		tipc_node_read_lock(node);
2530 		link = node->links[bearer_id].link;
2531 		if (!link) {
2532 			tipc_node_read_unlock(node);
2533 			err = -EINVAL;
2534 			goto err_free;
2535 		}
2536 
2537 		err = __tipc_nl_add_link(net, &msg, link, 0);
2538 		tipc_node_read_unlock(node);
2539 		if (err)
2540 			goto err_free;
2541 	}
2542 
2543 	return genlmsg_reply(msg.skb, info);
2544 
2545 err_free:
2546 	nlmsg_free(msg.skb);
2547 	return err;
2548 }
2549 
2550 int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info)
2551 {
2552 	int err;
2553 	char *link_name;
2554 	unsigned int bearer_id;
2555 	struct tipc_link *link;
2556 	struct tipc_node *node;
2557 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2558 	struct net *net = sock_net(skb->sk);
2559 	struct tipc_net *tn = tipc_net(net);
2560 	struct tipc_link_entry *le;
2561 
2562 	if (!info->attrs[TIPC_NLA_LINK])
2563 		return -EINVAL;
2564 
2565 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2566 					  info->attrs[TIPC_NLA_LINK],
2567 					  tipc_nl_link_policy, info->extack);
2568 	if (err)
2569 		return err;
2570 
2571 	if (!attrs[TIPC_NLA_LINK_NAME])
2572 		return -EINVAL;
2573 
2574 	link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2575 
2576 	err = -EINVAL;
2577 	if (!strcmp(link_name, tipc_bclink_name)) {
2578 		err = tipc_bclink_reset_stats(net, tipc_bc_sndlink(net));
2579 		if (err)
2580 			return err;
2581 		return 0;
2582 	} else if (strstr(link_name, tipc_bclink_name)) {
2583 		rcu_read_lock();
2584 		list_for_each_entry_rcu(node, &tn->node_list, list) {
2585 			tipc_node_read_lock(node);
2586 			link = node->bc_entry.link;
2587 			if (link && !strcmp(link_name, tipc_link_name(link))) {
2588 				err = tipc_bclink_reset_stats(net, link);
2589 				tipc_node_read_unlock(node);
2590 				break;
2591 			}
2592 			tipc_node_read_unlock(node);
2593 		}
2594 		rcu_read_unlock();
2595 		return err;
2596 	}
2597 
2598 	node = tipc_node_find_by_name(net, link_name, &bearer_id);
2599 	if (!node)
2600 		return -EINVAL;
2601 
2602 	le = &node->links[bearer_id];
2603 	tipc_node_read_lock(node);
2604 	spin_lock_bh(&le->lock);
2605 	link = node->links[bearer_id].link;
2606 	if (!link) {
2607 		spin_unlock_bh(&le->lock);
2608 		tipc_node_read_unlock(node);
2609 		return -EINVAL;
2610 	}
2611 	tipc_link_reset_stats(link);
2612 	spin_unlock_bh(&le->lock);
2613 	tipc_node_read_unlock(node);
2614 	return 0;
2615 }
2616 
2617 /* Caller should hold node lock  */
2618 static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
2619 				    struct tipc_node *node, u32 *prev_link,
2620 				    bool bc_link)
2621 {
2622 	u32 i;
2623 	int err;
2624 
2625 	for (i = *prev_link; i < MAX_BEARERS; i++) {
2626 		*prev_link = i;
2627 
2628 		if (!node->links[i].link)
2629 			continue;
2630 
2631 		err = __tipc_nl_add_link(net, msg,
2632 					 node->links[i].link, NLM_F_MULTI);
2633 		if (err)
2634 			return err;
2635 	}
2636 
2637 	if (bc_link) {
2638 		*prev_link = i;
2639 		err = tipc_nl_add_bc_link(net, msg, node->bc_entry.link);
2640 		if (err)
2641 			return err;
2642 	}
2643 
2644 	*prev_link = 0;
2645 
2646 	return 0;
2647 }
2648 
2649 int tipc_nl_node_dump_link(struct sk_buff *skb, struct netlink_callback *cb)
2650 {
2651 	struct net *net = sock_net(skb->sk);
2652 	struct nlattr **attrs = genl_dumpit_info(cb)->attrs;
2653 	struct nlattr *link[TIPC_NLA_LINK_MAX + 1];
2654 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2655 	struct tipc_node *node;
2656 	struct tipc_nl_msg msg;
2657 	u32 prev_node = cb->args[0];
2658 	u32 prev_link = cb->args[1];
2659 	int done = cb->args[2];
2660 	bool bc_link = cb->args[3];
2661 	int err;
2662 
2663 	if (done)
2664 		return 0;
2665 
2666 	if (!prev_node) {
2667 		/* Check if broadcast-receiver links dumping is needed */
2668 		if (attrs && attrs[TIPC_NLA_LINK]) {
2669 			err = nla_parse_nested_deprecated(link,
2670 							  TIPC_NLA_LINK_MAX,
2671 							  attrs[TIPC_NLA_LINK],
2672 							  tipc_nl_link_policy,
2673 							  NULL);
2674 			if (unlikely(err))
2675 				return err;
2676 			if (unlikely(!link[TIPC_NLA_LINK_BROADCAST]))
2677 				return -EINVAL;
2678 			bc_link = true;
2679 		}
2680 	}
2681 
2682 	msg.skb = skb;
2683 	msg.portid = NETLINK_CB(cb->skb).portid;
2684 	msg.seq = cb->nlh->nlmsg_seq;
2685 
2686 	rcu_read_lock();
2687 	if (prev_node) {
2688 		node = tipc_node_find(net, prev_node);
2689 		if (!node) {
2690 			/* We never set seq or call nl_dump_check_consistent()
2691 			 * this means that setting prev_seq here will cause the
2692 			 * consistence check to fail in the netlink callback
2693 			 * handler. Resulting in the last NLMSG_DONE message
2694 			 * having the NLM_F_DUMP_INTR flag set.
2695 			 */
2696 			cb->prev_seq = 1;
2697 			goto out;
2698 		}
2699 		tipc_node_put(node);
2700 
2701 		list_for_each_entry_continue_rcu(node, &tn->node_list,
2702 						 list) {
2703 			tipc_node_read_lock(node);
2704 			err = __tipc_nl_add_node_links(net, &msg, node,
2705 						       &prev_link, bc_link);
2706 			tipc_node_read_unlock(node);
2707 			if (err)
2708 				goto out;
2709 
2710 			prev_node = node->addr;
2711 		}
2712 	} else {
2713 		err = tipc_nl_add_bc_link(net, &msg, tn->bcl);
2714 		if (err)
2715 			goto out;
2716 
2717 		list_for_each_entry_rcu(node, &tn->node_list, list) {
2718 			tipc_node_read_lock(node);
2719 			err = __tipc_nl_add_node_links(net, &msg, node,
2720 						       &prev_link, bc_link);
2721 			tipc_node_read_unlock(node);
2722 			if (err)
2723 				goto out;
2724 
2725 			prev_node = node->addr;
2726 		}
2727 	}
2728 	done = 1;
2729 out:
2730 	rcu_read_unlock();
2731 
2732 	cb->args[0] = prev_node;
2733 	cb->args[1] = prev_link;
2734 	cb->args[2] = done;
2735 	cb->args[3] = bc_link;
2736 
2737 	return skb->len;
2738 }
2739 
2740 int tipc_nl_node_set_monitor(struct sk_buff *skb, struct genl_info *info)
2741 {
2742 	struct nlattr *attrs[TIPC_NLA_MON_MAX + 1];
2743 	struct net *net = sock_net(skb->sk);
2744 	int err;
2745 
2746 	if (!info->attrs[TIPC_NLA_MON])
2747 		return -EINVAL;
2748 
2749 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_MON_MAX,
2750 					  info->attrs[TIPC_NLA_MON],
2751 					  tipc_nl_monitor_policy,
2752 					  info->extack);
2753 	if (err)
2754 		return err;
2755 
2756 	if (attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]) {
2757 		u32 val;
2758 
2759 		val = nla_get_u32(attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]);
2760 		err = tipc_nl_monitor_set_threshold(net, val);
2761 		if (err)
2762 			return err;
2763 	}
2764 
2765 	return 0;
2766 }
2767 
2768 static int __tipc_nl_add_monitor_prop(struct net *net, struct tipc_nl_msg *msg)
2769 {
2770 	struct nlattr *attrs;
2771 	void *hdr;
2772 	u32 val;
2773 
2774 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2775 			  0, TIPC_NL_MON_GET);
2776 	if (!hdr)
2777 		return -EMSGSIZE;
2778 
2779 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_MON);
2780 	if (!attrs)
2781 		goto msg_full;
2782 
2783 	val = tipc_nl_monitor_get_threshold(net);
2784 
2785 	if (nla_put_u32(msg->skb, TIPC_NLA_MON_ACTIVATION_THRESHOLD, val))
2786 		goto attr_msg_full;
2787 
2788 	nla_nest_end(msg->skb, attrs);
2789 	genlmsg_end(msg->skb, hdr);
2790 
2791 	return 0;
2792 
2793 attr_msg_full:
2794 	nla_nest_cancel(msg->skb, attrs);
2795 msg_full:
2796 	genlmsg_cancel(msg->skb, hdr);
2797 
2798 	return -EMSGSIZE;
2799 }
2800 
2801 int tipc_nl_node_get_monitor(struct sk_buff *skb, struct genl_info *info)
2802 {
2803 	struct net *net = sock_net(skb->sk);
2804 	struct tipc_nl_msg msg;
2805 	int err;
2806 
2807 	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2808 	if (!msg.skb)
2809 		return -ENOMEM;
2810 	msg.portid = info->snd_portid;
2811 	msg.seq = info->snd_seq;
2812 
2813 	err = __tipc_nl_add_monitor_prop(net, &msg);
2814 	if (err) {
2815 		nlmsg_free(msg.skb);
2816 		return err;
2817 	}
2818 
2819 	return genlmsg_reply(msg.skb, info);
2820 }
2821 
2822 int tipc_nl_node_dump_monitor(struct sk_buff *skb, struct netlink_callback *cb)
2823 {
2824 	struct net *net = sock_net(skb->sk);
2825 	u32 prev_bearer = cb->args[0];
2826 	struct tipc_nl_msg msg;
2827 	int bearer_id;
2828 	int err;
2829 
2830 	if (prev_bearer == MAX_BEARERS)
2831 		return 0;
2832 
2833 	msg.skb = skb;
2834 	msg.portid = NETLINK_CB(cb->skb).portid;
2835 	msg.seq = cb->nlh->nlmsg_seq;
2836 
2837 	rtnl_lock();
2838 	for (bearer_id = prev_bearer; bearer_id < MAX_BEARERS; bearer_id++) {
2839 		err = __tipc_nl_add_monitor(net, &msg, bearer_id);
2840 		if (err)
2841 			break;
2842 	}
2843 	rtnl_unlock();
2844 	cb->args[0] = bearer_id;
2845 
2846 	return skb->len;
2847 }
2848 
2849 int tipc_nl_node_dump_monitor_peer(struct sk_buff *skb,
2850 				   struct netlink_callback *cb)
2851 {
2852 	struct net *net = sock_net(skb->sk);
2853 	u32 prev_node = cb->args[1];
2854 	u32 bearer_id = cb->args[2];
2855 	int done = cb->args[0];
2856 	struct tipc_nl_msg msg;
2857 	int err;
2858 
2859 	if (!prev_node) {
2860 		struct nlattr **attrs = genl_dumpit_info(cb)->attrs;
2861 		struct nlattr *mon[TIPC_NLA_MON_MAX + 1];
2862 
2863 		if (!attrs[TIPC_NLA_MON])
2864 			return -EINVAL;
2865 
2866 		err = nla_parse_nested_deprecated(mon, TIPC_NLA_MON_MAX,
2867 						  attrs[TIPC_NLA_MON],
2868 						  tipc_nl_monitor_policy,
2869 						  NULL);
2870 		if (err)
2871 			return err;
2872 
2873 		if (!mon[TIPC_NLA_MON_REF])
2874 			return -EINVAL;
2875 
2876 		bearer_id = nla_get_u32(mon[TIPC_NLA_MON_REF]);
2877 
2878 		if (bearer_id >= MAX_BEARERS)
2879 			return -EINVAL;
2880 	}
2881 
2882 	if (done)
2883 		return 0;
2884 
2885 	msg.skb = skb;
2886 	msg.portid = NETLINK_CB(cb->skb).portid;
2887 	msg.seq = cb->nlh->nlmsg_seq;
2888 
2889 	rtnl_lock();
2890 	err = tipc_nl_add_monitor_peer(net, &msg, bearer_id, &prev_node);
2891 	if (!err)
2892 		done = 1;
2893 
2894 	rtnl_unlock();
2895 	cb->args[0] = done;
2896 	cb->args[1] = prev_node;
2897 	cb->args[2] = bearer_id;
2898 
2899 	return skb->len;
2900 }
2901 
2902 #ifdef CONFIG_TIPC_CRYPTO
2903 static int tipc_nl_retrieve_key(struct nlattr **attrs,
2904 				struct tipc_aead_key **pkey)
2905 {
2906 	struct nlattr *attr = attrs[TIPC_NLA_NODE_KEY];
2907 	struct tipc_aead_key *key;
2908 
2909 	if (!attr)
2910 		return -ENODATA;
2911 
2912 	if (nla_len(attr) < sizeof(*key))
2913 		return -EINVAL;
2914 	key = (struct tipc_aead_key *)nla_data(attr);
2915 	if (key->keylen > TIPC_AEAD_KEYLEN_MAX ||
2916 	    nla_len(attr) < tipc_aead_key_size(key))
2917 		return -EINVAL;
2918 
2919 	*pkey = key;
2920 	return 0;
2921 }
2922 
2923 static int tipc_nl_retrieve_nodeid(struct nlattr **attrs, u8 **node_id)
2924 {
2925 	struct nlattr *attr = attrs[TIPC_NLA_NODE_ID];
2926 
2927 	if (!attr)
2928 		return -ENODATA;
2929 
2930 	if (nla_len(attr) < TIPC_NODEID_LEN)
2931 		return -EINVAL;
2932 
2933 	*node_id = (u8 *)nla_data(attr);
2934 	return 0;
2935 }
2936 
2937 static int tipc_nl_retrieve_rekeying(struct nlattr **attrs, u32 *intv)
2938 {
2939 	struct nlattr *attr = attrs[TIPC_NLA_NODE_REKEYING];
2940 
2941 	if (!attr)
2942 		return -ENODATA;
2943 
2944 	*intv = nla_get_u32(attr);
2945 	return 0;
2946 }
2947 
2948 static int __tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
2949 {
2950 	struct nlattr *attrs[TIPC_NLA_NODE_MAX + 1];
2951 	struct net *net = sock_net(skb->sk);
2952 	struct tipc_crypto *tx = tipc_net(net)->crypto_tx, *c = tx;
2953 	struct tipc_node *n = NULL;
2954 	struct tipc_aead_key *ukey;
2955 	bool rekeying = true, master_key = false;
2956 	u8 *id, *own_id, mode;
2957 	u32 intv = 0;
2958 	int rc = 0;
2959 
2960 	if (!info->attrs[TIPC_NLA_NODE])
2961 		return -EINVAL;
2962 
2963 	rc = nla_parse_nested(attrs, TIPC_NLA_NODE_MAX,
2964 			      info->attrs[TIPC_NLA_NODE],
2965 			      tipc_nl_node_policy, info->extack);
2966 	if (rc)
2967 		return rc;
2968 
2969 	own_id = tipc_own_id(net);
2970 	if (!own_id) {
2971 		GENL_SET_ERR_MSG(info, "not found own node identity (set id?)");
2972 		return -EPERM;
2973 	}
2974 
2975 	rc = tipc_nl_retrieve_rekeying(attrs, &intv);
2976 	if (rc == -ENODATA)
2977 		rekeying = false;
2978 
2979 	rc = tipc_nl_retrieve_key(attrs, &ukey);
2980 	if (rc == -ENODATA && rekeying)
2981 		goto rekeying;
2982 	else if (rc)
2983 		return rc;
2984 
2985 	rc = tipc_aead_key_validate(ukey, info);
2986 	if (rc)
2987 		return rc;
2988 
2989 	rc = tipc_nl_retrieve_nodeid(attrs, &id);
2990 	switch (rc) {
2991 	case -ENODATA:
2992 		mode = CLUSTER_KEY;
2993 		master_key = !!(attrs[TIPC_NLA_NODE_KEY_MASTER]);
2994 		break;
2995 	case 0:
2996 		mode = PER_NODE_KEY;
2997 		if (memcmp(id, own_id, NODE_ID_LEN)) {
2998 			n = tipc_node_find_by_id(net, id) ?:
2999 				tipc_node_create(net, 0, id, 0xffffu, 0, true);
3000 			if (unlikely(!n))
3001 				return -ENOMEM;
3002 			c = n->crypto_rx;
3003 		}
3004 		break;
3005 	default:
3006 		return rc;
3007 	}
3008 
3009 	/* Initiate the TX/RX key */
3010 	rc = tipc_crypto_key_init(c, ukey, mode, master_key);
3011 	if (n)
3012 		tipc_node_put(n);
3013 
3014 	if (unlikely(rc < 0)) {
3015 		GENL_SET_ERR_MSG(info, "unable to initiate or attach new key");
3016 		return rc;
3017 	} else if (c == tx) {
3018 		/* Distribute TX key but not master one */
3019 		if (!master_key && tipc_crypto_key_distr(tx, rc, NULL))
3020 			GENL_SET_ERR_MSG(info, "failed to replicate new key");
3021 rekeying:
3022 		/* Schedule TX rekeying if needed */
3023 		tipc_crypto_rekeying_sched(tx, rekeying, intv);
3024 	}
3025 
3026 	return 0;
3027 }
3028 
3029 int tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
3030 {
3031 	int err;
3032 
3033 	rtnl_lock();
3034 	err = __tipc_nl_node_set_key(skb, info);
3035 	rtnl_unlock();
3036 
3037 	return err;
3038 }
3039 
3040 static int __tipc_nl_node_flush_key(struct sk_buff *skb,
3041 				    struct genl_info *info)
3042 {
3043 	struct net *net = sock_net(skb->sk);
3044 	struct tipc_net *tn = tipc_net(net);
3045 	struct tipc_node *n;
3046 
3047 	tipc_crypto_key_flush(tn->crypto_tx);
3048 	rcu_read_lock();
3049 	list_for_each_entry_rcu(n, &tn->node_list, list)
3050 		tipc_crypto_key_flush(n->crypto_rx);
3051 	rcu_read_unlock();
3052 
3053 	return 0;
3054 }
3055 
3056 int tipc_nl_node_flush_key(struct sk_buff *skb, struct genl_info *info)
3057 {
3058 	int err;
3059 
3060 	rtnl_lock();
3061 	err = __tipc_nl_node_flush_key(skb, info);
3062 	rtnl_unlock();
3063 
3064 	return err;
3065 }
3066 #endif
3067 
3068 /**
3069  * tipc_node_dump - dump TIPC node data
3070  * @n: tipc node to be dumped
3071  * @more: dump more?
3072  *        - false: dump only tipc node data
3073  *        - true: dump node link data as well
3074  * @buf: returned buffer of dump data in format
3075  */
3076 int tipc_node_dump(struct tipc_node *n, bool more, char *buf)
3077 {
3078 	int i = 0;
3079 	size_t sz = (more) ? NODE_LMAX : NODE_LMIN;
3080 
3081 	if (!n) {
3082 		i += scnprintf(buf, sz, "node data: (null)\n");
3083 		return i;
3084 	}
3085 
3086 	i += scnprintf(buf, sz, "node data: %x", n->addr);
3087 	i += scnprintf(buf + i, sz - i, " %x", n->state);
3088 	i += scnprintf(buf + i, sz - i, " %d", n->active_links[0]);
3089 	i += scnprintf(buf + i, sz - i, " %d", n->active_links[1]);
3090 	i += scnprintf(buf + i, sz - i, " %x", n->action_flags);
3091 	i += scnprintf(buf + i, sz - i, " %u", n->failover_sent);
3092 	i += scnprintf(buf + i, sz - i, " %u", n->sync_point);
3093 	i += scnprintf(buf + i, sz - i, " %d", n->link_cnt);
3094 	i += scnprintf(buf + i, sz - i, " %u", n->working_links);
3095 	i += scnprintf(buf + i, sz - i, " %x", n->capabilities);
3096 	i += scnprintf(buf + i, sz - i, " %lu\n", n->keepalive_intv);
3097 
3098 	if (!more)
3099 		return i;
3100 
3101 	i += scnprintf(buf + i, sz - i, "link_entry[0]:\n");
3102 	i += scnprintf(buf + i, sz - i, " mtu: %u\n", n->links[0].mtu);
3103 	i += scnprintf(buf + i, sz - i, " media: ");
3104 	i += tipc_media_addr_printf(buf + i, sz - i, &n->links[0].maddr);
3105 	i += scnprintf(buf + i, sz - i, "\n");
3106 	i += tipc_link_dump(n->links[0].link, TIPC_DUMP_NONE, buf + i);
3107 	i += scnprintf(buf + i, sz - i, " inputq: ");
3108 	i += tipc_list_dump(&n->links[0].inputq, false, buf + i);
3109 
3110 	i += scnprintf(buf + i, sz - i, "link_entry[1]:\n");
3111 	i += scnprintf(buf + i, sz - i, " mtu: %u\n", n->links[1].mtu);
3112 	i += scnprintf(buf + i, sz - i, " media: ");
3113 	i += tipc_media_addr_printf(buf + i, sz - i, &n->links[1].maddr);
3114 	i += scnprintf(buf + i, sz - i, "\n");
3115 	i += tipc_link_dump(n->links[1].link, TIPC_DUMP_NONE, buf + i);
3116 	i += scnprintf(buf + i, sz - i, " inputq: ");
3117 	i += tipc_list_dump(&n->links[1].inputq, false, buf + i);
3118 
3119 	i += scnprintf(buf + i, sz - i, "bclink:\n ");
3120 	i += tipc_link_dump(n->bc_entry.link, TIPC_DUMP_NONE, buf + i);
3121 
3122 	return i;
3123 }
3124 
3125 void tipc_node_pre_cleanup_net(struct net *exit_net)
3126 {
3127 	struct tipc_node *n;
3128 	struct tipc_net *tn;
3129 	struct net *tmp;
3130 
3131 	rcu_read_lock();
3132 	for_each_net_rcu(tmp) {
3133 		if (tmp == exit_net)
3134 			continue;
3135 		tn = tipc_net(tmp);
3136 		if (!tn)
3137 			continue;
3138 		spin_lock_bh(&tn->node_list_lock);
3139 		list_for_each_entry_rcu(n, &tn->node_list, list) {
3140 			if (!n->peer_net)
3141 				continue;
3142 			if (n->peer_net != exit_net)
3143 				continue;
3144 			tipc_node_write_lock(n);
3145 			n->peer_net = NULL;
3146 			n->peer_hash_mix = 0;
3147 			tipc_node_write_unlock_fast(n);
3148 			break;
3149 		}
3150 		spin_unlock_bh(&tn->node_list_lock);
3151 	}
3152 	rcu_read_unlock();
3153 }
3154