xref: /linux/net/tipc/node.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
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  * @active_links: bearer ids of active links, used as index into links[] array
90  * @links: array containing references to all links to node
91  * @bc_entry: broadcast link entry
92  * @action_flags: bit mask of different types of node actions
93  * @state: connectivity state vs peer node
94  * @preliminary: a preliminary node or not
95  * @failover_sent: failover sent or not
96  * @sync_point: sequence number where synch/failover is finished
97  * @list: links to adjacent nodes in sorted list of cluster's nodes
98  * @working_links: number of working links to node (both active and standby)
99  * @link_cnt: number of links to node
100  * @capabilities: bitmap, indicating peer node's functional capabilities
101  * @signature: node instance identifier
102  * @link_id: local and remote bearer ids of changing link, if any
103  * @peer_id: 128-bit ID of peer
104  * @peer_id_string: ID string of peer
105  * @publ_list: list of publications
106  * @conn_sks: list of connections (FIXME)
107  * @timer: node's keepalive timer
108  * @keepalive_intv: keepalive interval in milliseconds
109  * @rcu: rcu struct for tipc_node
110  * @delete_at: indicates the time for deleting a down node
111  * @peer_net: peer's net namespace
112  * @peer_hash_mix: hash for this peer (FIXME)
113  * @crypto_rx: RX crypto handler
114  */
115 struct tipc_node {
116 	u32 addr;
117 	struct kref kref;
118 	rwlock_t lock;
119 	struct net *net;
120 	struct hlist_node hash;
121 	int active_links[2];
122 	struct tipc_link_entry links[MAX_BEARERS];
123 	struct tipc_bclink_entry bc_entry;
124 	int action_flags;
125 	struct list_head list;
126 	int state;
127 	bool preliminary;
128 	bool failover_sent;
129 	u16 sync_point;
130 	int link_cnt;
131 	u16 working_links;
132 	u16 capabilities;
133 	u32 signature;
134 	u32 link_id;
135 	u8 peer_id[16];
136 	char peer_id_string[NODE_ID_STR_LEN];
137 	struct list_head publ_list;
138 	struct list_head conn_sks;
139 	unsigned long keepalive_intv;
140 	struct timer_list timer;
141 	struct rcu_head rcu;
142 	unsigned long delete_at;
143 	struct net *peer_net;
144 	u32 peer_hash_mix;
145 #ifdef CONFIG_TIPC_CRYPTO
146 	struct tipc_crypto *crypto_rx;
147 #endif
148 };
149 
150 /* Node FSM states and events:
151  */
152 enum {
153 	SELF_DOWN_PEER_DOWN    = 0xdd,
154 	SELF_UP_PEER_UP        = 0xaa,
155 	SELF_DOWN_PEER_LEAVING = 0xd1,
156 	SELF_UP_PEER_COMING    = 0xac,
157 	SELF_COMING_PEER_UP    = 0xca,
158 	SELF_LEAVING_PEER_DOWN = 0x1d,
159 	NODE_FAILINGOVER       = 0xf0,
160 	NODE_SYNCHING          = 0xcc
161 };
162 
163 enum {
164 	SELF_ESTABL_CONTACT_EVT = 0xece,
165 	SELF_LOST_CONTACT_EVT   = 0x1ce,
166 	PEER_ESTABL_CONTACT_EVT = 0x9ece,
167 	PEER_LOST_CONTACT_EVT   = 0x91ce,
168 	NODE_FAILOVER_BEGIN_EVT = 0xfbe,
169 	NODE_FAILOVER_END_EVT   = 0xfee,
170 	NODE_SYNCH_BEGIN_EVT    = 0xcbe,
171 	NODE_SYNCH_END_EVT      = 0xcee
172 };
173 
174 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
175 				  struct sk_buff_head *xmitq,
176 				  struct tipc_media_addr **maddr);
177 static void tipc_node_link_down(struct tipc_node *n, int bearer_id,
178 				bool delete);
179 static void node_lost_contact(struct tipc_node *n, struct sk_buff_head *inputq);
180 static void tipc_node_delete(struct tipc_node *node);
181 static void tipc_node_timeout(struct timer_list *t);
182 static void tipc_node_fsm_evt(struct tipc_node *n, int evt);
183 static struct tipc_node *tipc_node_find(struct net *net, u32 addr);
184 static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id);
185 static bool node_is_up(struct tipc_node *n);
186 static void tipc_node_delete_from_list(struct tipc_node *node);
187 
188 struct tipc_sock_conn {
189 	u32 port;
190 	u32 peer_port;
191 	u32 peer_node;
192 	struct list_head list;
193 };
194 
195 static struct tipc_link *node_active_link(struct tipc_node *n, int sel)
196 {
197 	int bearer_id = n->active_links[sel & 1];
198 
199 	if (unlikely(bearer_id == INVALID_BEARER_ID))
200 		return NULL;
201 
202 	return n->links[bearer_id].link;
203 }
204 
205 int tipc_node_get_mtu(struct net *net, u32 addr, u32 sel, bool connected)
206 {
207 	struct tipc_node *n;
208 	int bearer_id;
209 	unsigned int mtu = MAX_MSG_SIZE;
210 
211 	n = tipc_node_find(net, addr);
212 	if (unlikely(!n))
213 		return mtu;
214 
215 	/* Allow MAX_MSG_SIZE when building connection oriented message
216 	 * if they are in the same core network
217 	 */
218 	if (n->peer_net && connected) {
219 		tipc_node_put(n);
220 		return mtu;
221 	}
222 
223 	bearer_id = n->active_links[sel & 1];
224 	if (likely(bearer_id != INVALID_BEARER_ID))
225 		mtu = n->links[bearer_id].mtu;
226 	tipc_node_put(n);
227 	return mtu;
228 }
229 
230 bool tipc_node_get_id(struct net *net, u32 addr, u8 *id)
231 {
232 	u8 *own_id = tipc_own_id(net);
233 	struct tipc_node *n;
234 
235 	if (!own_id)
236 		return true;
237 
238 	if (addr == tipc_own_addr(net)) {
239 		memcpy(id, own_id, TIPC_NODEID_LEN);
240 		return true;
241 	}
242 	n = tipc_node_find(net, addr);
243 	if (!n)
244 		return false;
245 
246 	memcpy(id, &n->peer_id, TIPC_NODEID_LEN);
247 	tipc_node_put(n);
248 	return true;
249 }
250 
251 u16 tipc_node_get_capabilities(struct net *net, u32 addr)
252 {
253 	struct tipc_node *n;
254 	u16 caps;
255 
256 	n = tipc_node_find(net, addr);
257 	if (unlikely(!n))
258 		return TIPC_NODE_CAPABILITIES;
259 	caps = n->capabilities;
260 	tipc_node_put(n);
261 	return caps;
262 }
263 
264 u32 tipc_node_get_addr(struct tipc_node *node)
265 {
266 	return (node) ? node->addr : 0;
267 }
268 
269 char *tipc_node_get_id_str(struct tipc_node *node)
270 {
271 	return node->peer_id_string;
272 }
273 
274 #ifdef CONFIG_TIPC_CRYPTO
275 /**
276  * tipc_node_crypto_rx - Retrieve crypto RX handle from node
277  * @__n: target tipc_node
278  * Note: node ref counter must be held first!
279  */
280 struct tipc_crypto *tipc_node_crypto_rx(struct tipc_node *__n)
281 {
282 	return (__n) ? __n->crypto_rx : NULL;
283 }
284 
285 struct tipc_crypto *tipc_node_crypto_rx_by_list(struct list_head *pos)
286 {
287 	return container_of(pos, struct tipc_node, list)->crypto_rx;
288 }
289 
290 struct tipc_crypto *tipc_node_crypto_rx_by_addr(struct net *net, u32 addr)
291 {
292 	struct tipc_node *n;
293 
294 	n = tipc_node_find(net, addr);
295 	return (n) ? n->crypto_rx : NULL;
296 }
297 #endif
298 
299 static void tipc_node_free(struct rcu_head *rp)
300 {
301 	struct tipc_node *n = container_of(rp, struct tipc_node, rcu);
302 
303 #ifdef CONFIG_TIPC_CRYPTO
304 	tipc_crypto_stop(&n->crypto_rx);
305 #endif
306 	kfree(n);
307 }
308 
309 static void tipc_node_kref_release(struct kref *kref)
310 {
311 	struct tipc_node *n = container_of(kref, struct tipc_node, kref);
312 
313 	kfree(n->bc_entry.link);
314 	call_rcu(&n->rcu, tipc_node_free);
315 }
316 
317 void tipc_node_put(struct tipc_node *node)
318 {
319 	kref_put(&node->kref, tipc_node_kref_release);
320 }
321 
322 void tipc_node_get(struct tipc_node *node)
323 {
324 	kref_get(&node->kref);
325 }
326 
327 /*
328  * tipc_node_find - locate specified node object, if it exists
329  */
330 static struct tipc_node *tipc_node_find(struct net *net, u32 addr)
331 {
332 	struct tipc_net *tn = tipc_net(net);
333 	struct tipc_node *node;
334 	unsigned int thash = tipc_hashfn(addr);
335 
336 	rcu_read_lock();
337 	hlist_for_each_entry_rcu(node, &tn->node_htable[thash], hash) {
338 		if (node->addr != addr || node->preliminary)
339 			continue;
340 		if (!kref_get_unless_zero(&node->kref))
341 			node = NULL;
342 		break;
343 	}
344 	rcu_read_unlock();
345 	return node;
346 }
347 
348 /* tipc_node_find_by_id - locate specified node object by its 128-bit id
349  * Note: this function is called only when a discovery request failed
350  * to find the node by its 32-bit id, and is not time critical
351  */
352 static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id)
353 {
354 	struct tipc_net *tn = tipc_net(net);
355 	struct tipc_node *n;
356 	bool found = false;
357 
358 	rcu_read_lock();
359 	list_for_each_entry_rcu(n, &tn->node_list, list) {
360 		read_lock_bh(&n->lock);
361 		if (!memcmp(id, n->peer_id, 16) &&
362 		    kref_get_unless_zero(&n->kref))
363 			found = true;
364 		read_unlock_bh(&n->lock);
365 		if (found)
366 			break;
367 	}
368 	rcu_read_unlock();
369 	return found ? n : NULL;
370 }
371 
372 static void tipc_node_read_lock(struct tipc_node *n)
373 	__acquires(n->lock)
374 {
375 	read_lock_bh(&n->lock);
376 }
377 
378 static void tipc_node_read_unlock(struct tipc_node *n)
379 	__releases(n->lock)
380 {
381 	read_unlock_bh(&n->lock);
382 }
383 
384 static void tipc_node_write_lock(struct tipc_node *n)
385 	__acquires(n->lock)
386 {
387 	write_lock_bh(&n->lock);
388 }
389 
390 static void tipc_node_write_unlock_fast(struct tipc_node *n)
391 	__releases(n->lock)
392 {
393 	write_unlock_bh(&n->lock);
394 }
395 
396 static void tipc_node_write_unlock(struct tipc_node *n)
397 	__releases(n->lock)
398 {
399 	struct tipc_socket_addr sk;
400 	struct net *net = n->net;
401 	u32 flags = n->action_flags;
402 	struct list_head *publ_list;
403 	struct tipc_uaddr ua;
404 	u32 bearer_id, node;
405 
406 	if (likely(!flags)) {
407 		write_unlock_bh(&n->lock);
408 		return;
409 	}
410 
411 	tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_NODE_SCOPE,
412 		   TIPC_LINK_STATE, n->addr, n->addr);
413 	sk.ref = n->link_id;
414 	sk.node = tipc_own_addr(net);
415 	node = n->addr;
416 	bearer_id = n->link_id & 0xffff;
417 	publ_list = &n->publ_list;
418 
419 	n->action_flags &= ~(TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP |
420 			     TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP);
421 
422 	write_unlock_bh(&n->lock);
423 
424 	if (flags & TIPC_NOTIFY_NODE_DOWN)
425 		tipc_publ_notify(net, publ_list, node, n->capabilities);
426 
427 	if (flags & TIPC_NOTIFY_NODE_UP)
428 		tipc_named_node_up(net, node, n->capabilities);
429 
430 	if (flags & TIPC_NOTIFY_LINK_UP) {
431 		tipc_mon_peer_up(net, node, bearer_id);
432 		tipc_nametbl_publish(net, &ua, &sk, sk.ref);
433 	}
434 	if (flags & TIPC_NOTIFY_LINK_DOWN) {
435 		tipc_mon_peer_down(net, node, bearer_id);
436 		tipc_nametbl_withdraw(net, &ua, &sk, sk.ref);
437 	}
438 }
439 
440 static void tipc_node_assign_peer_net(struct tipc_node *n, u32 hash_mixes)
441 {
442 	int net_id = tipc_netid(n->net);
443 	struct tipc_net *tn_peer;
444 	struct net *tmp;
445 	u32 hash_chk;
446 
447 	if (n->peer_net)
448 		return;
449 
450 	for_each_net_rcu(tmp) {
451 		tn_peer = tipc_net(tmp);
452 		if (!tn_peer)
453 			continue;
454 		/* Integrity checking whether node exists in namespace or not */
455 		if (tn_peer->net_id != net_id)
456 			continue;
457 		if (memcmp(n->peer_id, tn_peer->node_id, NODE_ID_LEN))
458 			continue;
459 		hash_chk = tipc_net_hash_mixes(tmp, tn_peer->random);
460 		if (hash_mixes ^ hash_chk)
461 			continue;
462 		n->peer_net = tmp;
463 		n->peer_hash_mix = hash_mixes;
464 		break;
465 	}
466 }
467 
468 struct tipc_node *tipc_node_create(struct net *net, u32 addr, u8 *peer_id,
469 				   u16 capabilities, u32 hash_mixes,
470 				   bool preliminary)
471 {
472 	struct tipc_net *tn = net_generic(net, tipc_net_id);
473 	struct tipc_link *l, *snd_l = tipc_bc_sndlink(net);
474 	struct tipc_node *n, *temp_node;
475 	unsigned long intv;
476 	int bearer_id;
477 	int i;
478 
479 	spin_lock_bh(&tn->node_list_lock);
480 	n = tipc_node_find(net, addr) ?:
481 		tipc_node_find_by_id(net, peer_id);
482 	if (n) {
483 		if (!n->preliminary)
484 			goto update;
485 		if (preliminary)
486 			goto exit;
487 		/* A preliminary node becomes "real" now, refresh its data */
488 		tipc_node_write_lock(n);
489 		if (!tipc_link_bc_create(net, tipc_own_addr(net), addr, peer_id, U16_MAX,
490 					 tipc_link_min_win(snd_l), tipc_link_max_win(snd_l),
491 					 n->capabilities, &n->bc_entry.inputq1,
492 					 &n->bc_entry.namedq, snd_l, &n->bc_entry.link)) {
493 			pr_warn("Broadcast rcv link refresh failed, no memory\n");
494 			tipc_node_write_unlock_fast(n);
495 			tipc_node_put(n);
496 			n = NULL;
497 			goto exit;
498 		}
499 		n->preliminary = false;
500 		n->addr = addr;
501 		hlist_del_rcu(&n->hash);
502 		hlist_add_head_rcu(&n->hash,
503 				   &tn->node_htable[tipc_hashfn(addr)]);
504 		list_del_rcu(&n->list);
505 		list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
506 			if (n->addr < temp_node->addr)
507 				break;
508 		}
509 		list_add_tail_rcu(&n->list, &temp_node->list);
510 		tipc_node_write_unlock_fast(n);
511 
512 update:
513 		if (n->peer_hash_mix ^ hash_mixes)
514 			tipc_node_assign_peer_net(n, hash_mixes);
515 		if (n->capabilities == capabilities)
516 			goto exit;
517 		/* Same node may come back with new capabilities */
518 		tipc_node_write_lock(n);
519 		n->capabilities = capabilities;
520 		for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
521 			l = n->links[bearer_id].link;
522 			if (l)
523 				tipc_link_update_caps(l, capabilities);
524 		}
525 		tipc_node_write_unlock_fast(n);
526 
527 		/* Calculate cluster capabilities */
528 		tn->capabilities = TIPC_NODE_CAPABILITIES;
529 		list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
530 			tn->capabilities &= temp_node->capabilities;
531 		}
532 
533 		tipc_bcast_toggle_rcast(net,
534 					(tn->capabilities & TIPC_BCAST_RCAST));
535 
536 		goto exit;
537 	}
538 	n = kzalloc(sizeof(*n), GFP_ATOMIC);
539 	if (!n) {
540 		pr_warn("Node creation failed, no memory\n");
541 		goto exit;
542 	}
543 	tipc_nodeid2string(n->peer_id_string, peer_id);
544 #ifdef CONFIG_TIPC_CRYPTO
545 	if (unlikely(tipc_crypto_start(&n->crypto_rx, net, n))) {
546 		pr_warn("Failed to start crypto RX(%s)!\n", n->peer_id_string);
547 		kfree(n);
548 		n = NULL;
549 		goto exit;
550 	}
551 #endif
552 	n->addr = addr;
553 	n->preliminary = preliminary;
554 	memcpy(&n->peer_id, peer_id, 16);
555 	n->net = net;
556 	n->peer_net = NULL;
557 	n->peer_hash_mix = 0;
558 	/* Assign kernel local namespace if exists */
559 	tipc_node_assign_peer_net(n, hash_mixes);
560 	n->capabilities = capabilities;
561 	kref_init(&n->kref);
562 	rwlock_init(&n->lock);
563 	INIT_HLIST_NODE(&n->hash);
564 	INIT_LIST_HEAD(&n->list);
565 	INIT_LIST_HEAD(&n->publ_list);
566 	INIT_LIST_HEAD(&n->conn_sks);
567 	skb_queue_head_init(&n->bc_entry.namedq);
568 	skb_queue_head_init(&n->bc_entry.inputq1);
569 	__skb_queue_head_init(&n->bc_entry.arrvq);
570 	skb_queue_head_init(&n->bc_entry.inputq2);
571 	for (i = 0; i < MAX_BEARERS; i++)
572 		spin_lock_init(&n->links[i].lock);
573 	n->state = SELF_DOWN_PEER_LEAVING;
574 	n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
575 	n->signature = INVALID_NODE_SIG;
576 	n->active_links[0] = INVALID_BEARER_ID;
577 	n->active_links[1] = INVALID_BEARER_ID;
578 	if (!preliminary &&
579 	    !tipc_link_bc_create(net, tipc_own_addr(net), addr, peer_id, U16_MAX,
580 				 tipc_link_min_win(snd_l), tipc_link_max_win(snd_l),
581 				 n->capabilities, &n->bc_entry.inputq1,
582 				 &n->bc_entry.namedq, snd_l, &n->bc_entry.link)) {
583 		pr_warn("Broadcast rcv link creation failed, no memory\n");
584 		tipc_node_put(n);
585 		n = NULL;
586 		goto exit;
587 	}
588 	tipc_node_get(n);
589 	timer_setup(&n->timer, tipc_node_timeout, 0);
590 	/* Start a slow timer anyway, crypto needs it */
591 	n->keepalive_intv = 10000;
592 	intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
593 	if (!mod_timer(&n->timer, intv))
594 		tipc_node_get(n);
595 	hlist_add_head_rcu(&n->hash, &tn->node_htable[tipc_hashfn(addr)]);
596 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
597 		if (n->addr < temp_node->addr)
598 			break;
599 	}
600 	list_add_tail_rcu(&n->list, &temp_node->list);
601 	/* Calculate cluster capabilities */
602 	tn->capabilities = TIPC_NODE_CAPABILITIES;
603 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
604 		tn->capabilities &= temp_node->capabilities;
605 	}
606 	tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
607 	trace_tipc_node_create(n, true, " ");
608 exit:
609 	spin_unlock_bh(&tn->node_list_lock);
610 	return n;
611 }
612 
613 static void tipc_node_calculate_timer(struct tipc_node *n, struct tipc_link *l)
614 {
615 	unsigned long tol = tipc_link_tolerance(l);
616 	unsigned long intv = ((tol / 4) > 500) ? 500 : tol / 4;
617 
618 	/* Link with lowest tolerance determines timer interval */
619 	if (intv < n->keepalive_intv)
620 		n->keepalive_intv = intv;
621 
622 	/* Ensure link's abort limit corresponds to current tolerance */
623 	tipc_link_set_abort_limit(l, tol / n->keepalive_intv);
624 }
625 
626 static void tipc_node_delete_from_list(struct tipc_node *node)
627 {
628 #ifdef CONFIG_TIPC_CRYPTO
629 	tipc_crypto_key_flush(node->crypto_rx);
630 #endif
631 	list_del_rcu(&node->list);
632 	hlist_del_rcu(&node->hash);
633 	tipc_node_put(node);
634 }
635 
636 static void tipc_node_delete(struct tipc_node *node)
637 {
638 	trace_tipc_node_delete(node, true, " ");
639 	tipc_node_delete_from_list(node);
640 
641 	del_timer_sync(&node->timer);
642 	tipc_node_put(node);
643 }
644 
645 void tipc_node_stop(struct net *net)
646 {
647 	struct tipc_net *tn = tipc_net(net);
648 	struct tipc_node *node, *t_node;
649 
650 	spin_lock_bh(&tn->node_list_lock);
651 	list_for_each_entry_safe(node, t_node, &tn->node_list, list)
652 		tipc_node_delete(node);
653 	spin_unlock_bh(&tn->node_list_lock);
654 }
655 
656 void tipc_node_subscribe(struct net *net, struct list_head *subscr, u32 addr)
657 {
658 	struct tipc_node *n;
659 
660 	if (in_own_node(net, addr))
661 		return;
662 
663 	n = tipc_node_find(net, addr);
664 	if (!n) {
665 		pr_warn("Node subscribe rejected, unknown node 0x%x\n", addr);
666 		return;
667 	}
668 	tipc_node_write_lock(n);
669 	list_add_tail(subscr, &n->publ_list);
670 	tipc_node_write_unlock_fast(n);
671 	tipc_node_put(n);
672 }
673 
674 void tipc_node_unsubscribe(struct net *net, struct list_head *subscr, u32 addr)
675 {
676 	struct tipc_node *n;
677 
678 	if (in_own_node(net, addr))
679 		return;
680 
681 	n = tipc_node_find(net, addr);
682 	if (!n) {
683 		pr_warn("Node unsubscribe rejected, unknown node 0x%x\n", addr);
684 		return;
685 	}
686 	tipc_node_write_lock(n);
687 	list_del_init(subscr);
688 	tipc_node_write_unlock_fast(n);
689 	tipc_node_put(n);
690 }
691 
692 int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port)
693 {
694 	struct tipc_node *node;
695 	struct tipc_sock_conn *conn;
696 	int err = 0;
697 
698 	if (in_own_node(net, dnode))
699 		return 0;
700 
701 	node = tipc_node_find(net, dnode);
702 	if (!node) {
703 		pr_warn("Connecting sock to node 0x%x failed\n", dnode);
704 		return -EHOSTUNREACH;
705 	}
706 	conn = kmalloc(sizeof(*conn), GFP_ATOMIC);
707 	if (!conn) {
708 		err = -EHOSTUNREACH;
709 		goto exit;
710 	}
711 	conn->peer_node = dnode;
712 	conn->port = port;
713 	conn->peer_port = peer_port;
714 
715 	tipc_node_write_lock(node);
716 	list_add_tail(&conn->list, &node->conn_sks);
717 	tipc_node_write_unlock(node);
718 exit:
719 	tipc_node_put(node);
720 	return err;
721 }
722 
723 void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port)
724 {
725 	struct tipc_node *node;
726 	struct tipc_sock_conn *conn, *safe;
727 
728 	if (in_own_node(net, dnode))
729 		return;
730 
731 	node = tipc_node_find(net, dnode);
732 	if (!node)
733 		return;
734 
735 	tipc_node_write_lock(node);
736 	list_for_each_entry_safe(conn, safe, &node->conn_sks, list) {
737 		if (port != conn->port)
738 			continue;
739 		list_del(&conn->list);
740 		kfree(conn);
741 	}
742 	tipc_node_write_unlock(node);
743 	tipc_node_put(node);
744 }
745 
746 static void  tipc_node_clear_links(struct tipc_node *node)
747 {
748 	int i;
749 
750 	for (i = 0; i < MAX_BEARERS; i++) {
751 		struct tipc_link_entry *le = &node->links[i];
752 
753 		if (le->link) {
754 			kfree(le->link);
755 			le->link = NULL;
756 			node->link_cnt--;
757 		}
758 	}
759 }
760 
761 /* tipc_node_cleanup - delete nodes that does not
762  * have active links for NODE_CLEANUP_AFTER time
763  */
764 static bool tipc_node_cleanup(struct tipc_node *peer)
765 {
766 	struct tipc_node *temp_node;
767 	struct tipc_net *tn = tipc_net(peer->net);
768 	bool deleted = false;
769 
770 	/* If lock held by tipc_node_stop() the node will be deleted anyway */
771 	if (!spin_trylock_bh(&tn->node_list_lock))
772 		return false;
773 
774 	tipc_node_write_lock(peer);
775 
776 	if (!node_is_up(peer) && time_after(jiffies, peer->delete_at)) {
777 		tipc_node_clear_links(peer);
778 		tipc_node_delete_from_list(peer);
779 		deleted = true;
780 	}
781 	tipc_node_write_unlock(peer);
782 
783 	if (!deleted) {
784 		spin_unlock_bh(&tn->node_list_lock);
785 		return deleted;
786 	}
787 
788 	/* Calculate cluster capabilities */
789 	tn->capabilities = TIPC_NODE_CAPABILITIES;
790 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
791 		tn->capabilities &= temp_node->capabilities;
792 	}
793 	tipc_bcast_toggle_rcast(peer->net,
794 				(tn->capabilities & TIPC_BCAST_RCAST));
795 	spin_unlock_bh(&tn->node_list_lock);
796 	return deleted;
797 }
798 
799 /* tipc_node_timeout - handle expiration of node timer
800  */
801 static void tipc_node_timeout(struct timer_list *t)
802 {
803 	struct tipc_node *n = from_timer(n, t, timer);
804 	struct tipc_link_entry *le;
805 	struct sk_buff_head xmitq;
806 	int remains = n->link_cnt;
807 	int bearer_id;
808 	int rc = 0;
809 
810 	trace_tipc_node_timeout(n, false, " ");
811 	if (!node_is_up(n) && tipc_node_cleanup(n)) {
812 		/*Removing the reference of Timer*/
813 		tipc_node_put(n);
814 		return;
815 	}
816 
817 #ifdef CONFIG_TIPC_CRYPTO
818 	/* Take any crypto key related actions first */
819 	tipc_crypto_timeout(n->crypto_rx);
820 #endif
821 	__skb_queue_head_init(&xmitq);
822 
823 	/* Initial node interval to value larger (10 seconds), then it will be
824 	 * recalculated with link lowest tolerance
825 	 */
826 	tipc_node_read_lock(n);
827 	n->keepalive_intv = 10000;
828 	tipc_node_read_unlock(n);
829 	for (bearer_id = 0; remains && (bearer_id < MAX_BEARERS); bearer_id++) {
830 		tipc_node_read_lock(n);
831 		le = &n->links[bearer_id];
832 		if (le->link) {
833 			spin_lock_bh(&le->lock);
834 			/* Link tolerance may change asynchronously: */
835 			tipc_node_calculate_timer(n, le->link);
836 			rc = tipc_link_timeout(le->link, &xmitq);
837 			spin_unlock_bh(&le->lock);
838 			remains--;
839 		}
840 		tipc_node_read_unlock(n);
841 		tipc_bearer_xmit(n->net, bearer_id, &xmitq, &le->maddr, n);
842 		if (rc & TIPC_LINK_DOWN_EVT)
843 			tipc_node_link_down(n, bearer_id, false);
844 	}
845 	mod_timer(&n->timer, jiffies + msecs_to_jiffies(n->keepalive_intv));
846 }
847 
848 /**
849  * __tipc_node_link_up - handle addition of link
850  * @n: target tipc_node
851  * @bearer_id: id of the bearer
852  * @xmitq: queue for messages to be xmited on
853  * Node lock must be held by caller
854  * Link becomes active (alone or shared) or standby, depending on its priority.
855  */
856 static void __tipc_node_link_up(struct tipc_node *n, int bearer_id,
857 				struct sk_buff_head *xmitq)
858 {
859 	int *slot0 = &n->active_links[0];
860 	int *slot1 = &n->active_links[1];
861 	struct tipc_link *ol = node_active_link(n, 0);
862 	struct tipc_link *nl = n->links[bearer_id].link;
863 
864 	if (!nl || tipc_link_is_up(nl))
865 		return;
866 
867 	tipc_link_fsm_evt(nl, LINK_ESTABLISH_EVT);
868 	if (!tipc_link_is_up(nl))
869 		return;
870 
871 	n->working_links++;
872 	n->action_flags |= TIPC_NOTIFY_LINK_UP;
873 	n->link_id = tipc_link_id(nl);
874 
875 	/* Leave room for tunnel header when returning 'mtu' to users: */
876 	n->links[bearer_id].mtu = tipc_link_mss(nl);
877 
878 	tipc_bearer_add_dest(n->net, bearer_id, n->addr);
879 	tipc_bcast_inc_bearer_dst_cnt(n->net, bearer_id);
880 
881 	pr_debug("Established link <%s> on network plane %c\n",
882 		 tipc_link_name(nl), tipc_link_plane(nl));
883 	trace_tipc_node_link_up(n, true, " ");
884 
885 	/* Ensure that a STATE message goes first */
886 	tipc_link_build_state_msg(nl, xmitq);
887 
888 	/* First link? => give it both slots */
889 	if (!ol) {
890 		*slot0 = bearer_id;
891 		*slot1 = bearer_id;
892 		tipc_node_fsm_evt(n, SELF_ESTABL_CONTACT_EVT);
893 		n->action_flags |= TIPC_NOTIFY_NODE_UP;
894 		tipc_link_set_active(nl, true);
895 		tipc_bcast_add_peer(n->net, nl, xmitq);
896 		return;
897 	}
898 
899 	/* Second link => redistribute slots */
900 	if (tipc_link_prio(nl) > tipc_link_prio(ol)) {
901 		pr_debug("Old link <%s> becomes standby\n", tipc_link_name(ol));
902 		*slot0 = bearer_id;
903 		*slot1 = bearer_id;
904 		tipc_link_set_active(nl, true);
905 		tipc_link_set_active(ol, false);
906 	} else if (tipc_link_prio(nl) == tipc_link_prio(ol)) {
907 		tipc_link_set_active(nl, true);
908 		*slot1 = bearer_id;
909 	} else {
910 		pr_debug("New link <%s> is standby\n", tipc_link_name(nl));
911 	}
912 
913 	/* Prepare synchronization with first link */
914 	tipc_link_tnl_prepare(ol, nl, SYNCH_MSG, xmitq);
915 }
916 
917 /**
918  * tipc_node_link_up - handle addition of link
919  * @n: target tipc_node
920  * @bearer_id: id of the bearer
921  * @xmitq: queue for messages to be xmited on
922  *
923  * Link becomes active (alone or shared) or standby, depending on its priority.
924  */
925 static void tipc_node_link_up(struct tipc_node *n, int bearer_id,
926 			      struct sk_buff_head *xmitq)
927 {
928 	struct tipc_media_addr *maddr;
929 
930 	tipc_node_write_lock(n);
931 	__tipc_node_link_up(n, bearer_id, xmitq);
932 	maddr = &n->links[bearer_id].maddr;
933 	tipc_bearer_xmit(n->net, bearer_id, xmitq, maddr, n);
934 	tipc_node_write_unlock(n);
935 }
936 
937 /**
938  * tipc_node_link_failover() - start failover in case "half-failover"
939  *
940  * This function is only called in a very special situation where link
941  * failover can be already started on peer node but not on this node.
942  * This can happen when e.g.::
943  *
944  *	1. Both links <1A-2A>, <1B-2B> down
945  *	2. Link endpoint 2A up, but 1A still down (e.g. due to network
946  *	disturbance, wrong session, etc.)
947  *	3. Link <1B-2B> up
948  *	4. Link endpoint 2A down (e.g. due to link tolerance timeout)
949  *	5. Node 2 starts failover onto link <1B-2B>
950  *
951  *	==> Node 1 does never start link/node failover!
952  *
953  * @n: tipc node structure
954  * @l: link peer endpoint failingover (- can be NULL)
955  * @tnl: tunnel link
956  * @xmitq: queue for messages to be xmited on tnl link later
957  */
958 static void tipc_node_link_failover(struct tipc_node *n, struct tipc_link *l,
959 				    struct tipc_link *tnl,
960 				    struct sk_buff_head *xmitq)
961 {
962 	/* Avoid to be "self-failover" that can never end */
963 	if (!tipc_link_is_up(tnl))
964 		return;
965 
966 	/* Don't rush, failure link may be in the process of resetting */
967 	if (l && !tipc_link_is_reset(l))
968 		return;
969 
970 	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
971 	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
972 
973 	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
974 	tipc_link_failover_prepare(l, tnl, xmitq);
975 
976 	if (l)
977 		tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
978 	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
979 }
980 
981 /**
982  * __tipc_node_link_down - handle loss of link
983  * @n: target tipc_node
984  * @bearer_id: id of the bearer
985  * @xmitq: queue for messages to be xmited on
986  * @maddr: output media address of the bearer
987  */
988 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
989 				  struct sk_buff_head *xmitq,
990 				  struct tipc_media_addr **maddr)
991 {
992 	struct tipc_link_entry *le = &n->links[*bearer_id];
993 	int *slot0 = &n->active_links[0];
994 	int *slot1 = &n->active_links[1];
995 	int i, highest = 0, prio;
996 	struct tipc_link *l, *_l, *tnl;
997 
998 	l = n->links[*bearer_id].link;
999 	if (!l || tipc_link_is_reset(l))
1000 		return;
1001 
1002 	n->working_links--;
1003 	n->action_flags |= TIPC_NOTIFY_LINK_DOWN;
1004 	n->link_id = tipc_link_id(l);
1005 
1006 	tipc_bearer_remove_dest(n->net, *bearer_id, n->addr);
1007 
1008 	pr_debug("Lost link <%s> on network plane %c\n",
1009 		 tipc_link_name(l), tipc_link_plane(l));
1010 
1011 	/* Select new active link if any available */
1012 	*slot0 = INVALID_BEARER_ID;
1013 	*slot1 = INVALID_BEARER_ID;
1014 	for (i = 0; i < MAX_BEARERS; i++) {
1015 		_l = n->links[i].link;
1016 		if (!_l || !tipc_link_is_up(_l))
1017 			continue;
1018 		if (_l == l)
1019 			continue;
1020 		prio = tipc_link_prio(_l);
1021 		if (prio < highest)
1022 			continue;
1023 		if (prio > highest) {
1024 			highest = prio;
1025 			*slot0 = i;
1026 			*slot1 = i;
1027 			continue;
1028 		}
1029 		*slot1 = i;
1030 	}
1031 
1032 	if (!node_is_up(n)) {
1033 		if (tipc_link_peer_is_down(l))
1034 			tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
1035 		tipc_node_fsm_evt(n, SELF_LOST_CONTACT_EVT);
1036 		trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down!");
1037 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1038 		tipc_link_reset(l);
1039 		tipc_link_build_reset_msg(l, xmitq);
1040 		*maddr = &n->links[*bearer_id].maddr;
1041 		node_lost_contact(n, &le->inputq);
1042 		tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
1043 		return;
1044 	}
1045 	tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
1046 
1047 	/* There is still a working link => initiate failover */
1048 	*bearer_id = n->active_links[0];
1049 	tnl = n->links[*bearer_id].link;
1050 	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
1051 	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
1052 	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
1053 	tipc_link_tnl_prepare(l, tnl, FAILOVER_MSG, xmitq);
1054 	trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down -> failover!");
1055 	tipc_link_reset(l);
1056 	tipc_link_fsm_evt(l, LINK_RESET_EVT);
1057 	tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
1058 	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
1059 	*maddr = &n->links[*bearer_id].maddr;
1060 }
1061 
1062 static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete)
1063 {
1064 	struct tipc_link_entry *le = &n->links[bearer_id];
1065 	struct tipc_media_addr *maddr = NULL;
1066 	struct tipc_link *l = le->link;
1067 	int old_bearer_id = bearer_id;
1068 	struct sk_buff_head xmitq;
1069 
1070 	if (!l)
1071 		return;
1072 
1073 	__skb_queue_head_init(&xmitq);
1074 
1075 	tipc_node_write_lock(n);
1076 	if (!tipc_link_is_establishing(l)) {
1077 		__tipc_node_link_down(n, &bearer_id, &xmitq, &maddr);
1078 	} else {
1079 		/* Defuse pending tipc_node_link_up() */
1080 		tipc_link_reset(l);
1081 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1082 	}
1083 	if (delete) {
1084 		kfree(l);
1085 		le->link = NULL;
1086 		n->link_cnt--;
1087 	}
1088 	trace_tipc_node_link_down(n, true, "node link down or deleted!");
1089 	tipc_node_write_unlock(n);
1090 	if (delete)
1091 		tipc_mon_remove_peer(n->net, n->addr, old_bearer_id);
1092 	if (!skb_queue_empty(&xmitq))
1093 		tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr, n);
1094 	tipc_sk_rcv(n->net, &le->inputq);
1095 }
1096 
1097 static bool node_is_up(struct tipc_node *n)
1098 {
1099 	return n->active_links[0] != INVALID_BEARER_ID;
1100 }
1101 
1102 bool tipc_node_is_up(struct net *net, u32 addr)
1103 {
1104 	struct tipc_node *n;
1105 	bool retval = false;
1106 
1107 	if (in_own_node(net, addr))
1108 		return true;
1109 
1110 	n = tipc_node_find(net, addr);
1111 	if (!n)
1112 		return false;
1113 	retval = node_is_up(n);
1114 	tipc_node_put(n);
1115 	return retval;
1116 }
1117 
1118 static u32 tipc_node_suggest_addr(struct net *net, u32 addr)
1119 {
1120 	struct tipc_node *n;
1121 
1122 	addr ^= tipc_net(net)->random;
1123 	while ((n = tipc_node_find(net, addr))) {
1124 		tipc_node_put(n);
1125 		addr++;
1126 	}
1127 	return addr;
1128 }
1129 
1130 /* tipc_node_try_addr(): Check if addr can be used by peer, suggest other if not
1131  * Returns suggested address if any, otherwise 0
1132  */
1133 u32 tipc_node_try_addr(struct net *net, u8 *id, u32 addr)
1134 {
1135 	struct tipc_net *tn = tipc_net(net);
1136 	struct tipc_node *n;
1137 	bool preliminary;
1138 	u32 sugg_addr;
1139 
1140 	/* Suggest new address if some other peer is using this one */
1141 	n = tipc_node_find(net, addr);
1142 	if (n) {
1143 		if (!memcmp(n->peer_id, id, NODE_ID_LEN))
1144 			addr = 0;
1145 		tipc_node_put(n);
1146 		if (!addr)
1147 			return 0;
1148 		return tipc_node_suggest_addr(net, addr);
1149 	}
1150 
1151 	/* Suggest previously used address if peer is known */
1152 	n = tipc_node_find_by_id(net, id);
1153 	if (n) {
1154 		sugg_addr = n->addr;
1155 		preliminary = n->preliminary;
1156 		tipc_node_put(n);
1157 		if (!preliminary)
1158 			return sugg_addr;
1159 	}
1160 
1161 	/* Even this node may be in conflict */
1162 	if (tn->trial_addr == addr)
1163 		return tipc_node_suggest_addr(net, addr);
1164 
1165 	return 0;
1166 }
1167 
1168 void tipc_node_check_dest(struct net *net, u32 addr,
1169 			  u8 *peer_id, struct tipc_bearer *b,
1170 			  u16 capabilities, u32 signature, u32 hash_mixes,
1171 			  struct tipc_media_addr *maddr,
1172 			  bool *respond, bool *dupl_addr)
1173 {
1174 	struct tipc_node *n;
1175 	struct tipc_link *l;
1176 	struct tipc_link_entry *le;
1177 	bool addr_match = false;
1178 	bool sign_match = false;
1179 	bool link_up = false;
1180 	bool link_is_reset = false;
1181 	bool accept_addr = false;
1182 	bool reset = false;
1183 	char *if_name;
1184 	unsigned long intv;
1185 	u16 session;
1186 
1187 	*dupl_addr = false;
1188 	*respond = false;
1189 
1190 	n = tipc_node_create(net, addr, peer_id, capabilities, hash_mixes,
1191 			     false);
1192 	if (!n)
1193 		return;
1194 
1195 	tipc_node_write_lock(n);
1196 
1197 	le = &n->links[b->identity];
1198 
1199 	/* Prepare to validate requesting node's signature and media address */
1200 	l = le->link;
1201 	link_up = l && tipc_link_is_up(l);
1202 	link_is_reset = l && tipc_link_is_reset(l);
1203 	addr_match = l && !memcmp(&le->maddr, maddr, sizeof(*maddr));
1204 	sign_match = (signature == n->signature);
1205 
1206 	/* These three flags give us eight permutations: */
1207 
1208 	if (sign_match && addr_match && link_up) {
1209 		/* All is fine. Ignore requests. */
1210 		/* Peer node is not a container/local namespace */
1211 		if (!n->peer_hash_mix)
1212 			n->peer_hash_mix = hash_mixes;
1213 	} else if (sign_match && addr_match && !link_up) {
1214 		/* Respond. The link will come up in due time */
1215 		*respond = true;
1216 	} else if (sign_match && !addr_match && link_up) {
1217 		/* Peer has changed i/f address without rebooting.
1218 		 * If so, the link will reset soon, and the next
1219 		 * discovery will be accepted. So we can ignore it.
1220 		 * It may also be a cloned or malicious peer having
1221 		 * chosen the same node address and signature as an
1222 		 * existing one.
1223 		 * Ignore requests until the link goes down, if ever.
1224 		 */
1225 		*dupl_addr = true;
1226 	} else if (sign_match && !addr_match && !link_up) {
1227 		/* Peer link has changed i/f address without rebooting.
1228 		 * It may also be a cloned or malicious peer; we can't
1229 		 * distinguish between the two.
1230 		 * The signature is correct, so we must accept.
1231 		 */
1232 		accept_addr = true;
1233 		*respond = true;
1234 		reset = true;
1235 	} else if (!sign_match && addr_match && link_up) {
1236 		/* Peer node rebooted. Two possibilities:
1237 		 *  - Delayed re-discovery; this link endpoint has already
1238 		 *    reset and re-established contact with the peer, before
1239 		 *    receiving a discovery message from that node.
1240 		 *    (The peer happened to receive one from this node first).
1241 		 *  - The peer came back so fast that our side has not
1242 		 *    discovered it yet. Probing from this side will soon
1243 		 *    reset the link, since there can be no working link
1244 		 *    endpoint at the peer end, and the link will re-establish.
1245 		 *  Accept the signature, since it comes from a known peer.
1246 		 */
1247 		n->signature = signature;
1248 	} else if (!sign_match && addr_match && !link_up) {
1249 		/*  The peer node has rebooted.
1250 		 *  Accept signature, since it is a known peer.
1251 		 */
1252 		n->signature = signature;
1253 		*respond = true;
1254 	} else if (!sign_match && !addr_match && link_up) {
1255 		/* Peer rebooted with new address, or a new/duplicate peer.
1256 		 * Ignore until the link goes down, if ever.
1257 		 */
1258 		*dupl_addr = true;
1259 	} else if (!sign_match && !addr_match && !link_up) {
1260 		/* Peer rebooted with new address, or it is a new peer.
1261 		 * Accept signature and address.
1262 		 */
1263 		n->signature = signature;
1264 		accept_addr = true;
1265 		*respond = true;
1266 		reset = true;
1267 	}
1268 
1269 	if (!accept_addr)
1270 		goto exit;
1271 
1272 	/* Now create new link if not already existing */
1273 	if (!l) {
1274 		if (n->link_cnt == 2)
1275 			goto exit;
1276 
1277 		if_name = strchr(b->name, ':') + 1;
1278 		get_random_bytes(&session, sizeof(u16));
1279 		if (!tipc_link_create(net, if_name, b->identity, b->tolerance,
1280 				      b->net_plane, b->mtu, b->priority,
1281 				      b->min_win, b->max_win, session,
1282 				      tipc_own_addr(net), addr, peer_id,
1283 				      n->capabilities,
1284 				      tipc_bc_sndlink(n->net), n->bc_entry.link,
1285 				      &le->inputq,
1286 				      &n->bc_entry.namedq, &l)) {
1287 			*respond = false;
1288 			goto exit;
1289 		}
1290 		trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link created!");
1291 		tipc_link_reset(l);
1292 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1293 		if (n->state == NODE_FAILINGOVER)
1294 			tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
1295 		link_is_reset = tipc_link_is_reset(l);
1296 		le->link = l;
1297 		n->link_cnt++;
1298 		tipc_node_calculate_timer(n, l);
1299 		if (n->link_cnt == 1) {
1300 			intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
1301 			if (!mod_timer(&n->timer, intv))
1302 				tipc_node_get(n);
1303 		}
1304 	}
1305 	memcpy(&le->maddr, maddr, sizeof(*maddr));
1306 exit:
1307 	tipc_node_write_unlock(n);
1308 	if (reset && !link_is_reset)
1309 		tipc_node_link_down(n, b->identity, false);
1310 	tipc_node_put(n);
1311 }
1312 
1313 void tipc_node_delete_links(struct net *net, int bearer_id)
1314 {
1315 	struct tipc_net *tn = net_generic(net, tipc_net_id);
1316 	struct tipc_node *n;
1317 
1318 	rcu_read_lock();
1319 	list_for_each_entry_rcu(n, &tn->node_list, list) {
1320 		tipc_node_link_down(n, bearer_id, true);
1321 	}
1322 	rcu_read_unlock();
1323 }
1324 
1325 static void tipc_node_reset_links(struct tipc_node *n)
1326 {
1327 	int i;
1328 
1329 	pr_warn("Resetting all links to %x\n", n->addr);
1330 
1331 	trace_tipc_node_reset_links(n, true, " ");
1332 	for (i = 0; i < MAX_BEARERS; i++) {
1333 		tipc_node_link_down(n, i, false);
1334 	}
1335 }
1336 
1337 /* tipc_node_fsm_evt - node finite state machine
1338  * Determines when contact is allowed with peer node
1339  */
1340 static void tipc_node_fsm_evt(struct tipc_node *n, int evt)
1341 {
1342 	int state = n->state;
1343 
1344 	switch (state) {
1345 	case SELF_DOWN_PEER_DOWN:
1346 		switch (evt) {
1347 		case SELF_ESTABL_CONTACT_EVT:
1348 			state = SELF_UP_PEER_COMING;
1349 			break;
1350 		case PEER_ESTABL_CONTACT_EVT:
1351 			state = SELF_COMING_PEER_UP;
1352 			break;
1353 		case SELF_LOST_CONTACT_EVT:
1354 		case PEER_LOST_CONTACT_EVT:
1355 			break;
1356 		case NODE_SYNCH_END_EVT:
1357 		case NODE_SYNCH_BEGIN_EVT:
1358 		case NODE_FAILOVER_BEGIN_EVT:
1359 		case NODE_FAILOVER_END_EVT:
1360 		default:
1361 			goto illegal_evt;
1362 		}
1363 		break;
1364 	case SELF_UP_PEER_UP:
1365 		switch (evt) {
1366 		case SELF_LOST_CONTACT_EVT:
1367 			state = SELF_DOWN_PEER_LEAVING;
1368 			break;
1369 		case PEER_LOST_CONTACT_EVT:
1370 			state = SELF_LEAVING_PEER_DOWN;
1371 			break;
1372 		case NODE_SYNCH_BEGIN_EVT:
1373 			state = NODE_SYNCHING;
1374 			break;
1375 		case NODE_FAILOVER_BEGIN_EVT:
1376 			state = NODE_FAILINGOVER;
1377 			break;
1378 		case SELF_ESTABL_CONTACT_EVT:
1379 		case PEER_ESTABL_CONTACT_EVT:
1380 		case NODE_SYNCH_END_EVT:
1381 		case NODE_FAILOVER_END_EVT:
1382 			break;
1383 		default:
1384 			goto illegal_evt;
1385 		}
1386 		break;
1387 	case SELF_DOWN_PEER_LEAVING:
1388 		switch (evt) {
1389 		case PEER_LOST_CONTACT_EVT:
1390 			state = SELF_DOWN_PEER_DOWN;
1391 			break;
1392 		case SELF_ESTABL_CONTACT_EVT:
1393 		case PEER_ESTABL_CONTACT_EVT:
1394 		case SELF_LOST_CONTACT_EVT:
1395 			break;
1396 		case NODE_SYNCH_END_EVT:
1397 		case NODE_SYNCH_BEGIN_EVT:
1398 		case NODE_FAILOVER_BEGIN_EVT:
1399 		case NODE_FAILOVER_END_EVT:
1400 		default:
1401 			goto illegal_evt;
1402 		}
1403 		break;
1404 	case SELF_UP_PEER_COMING:
1405 		switch (evt) {
1406 		case PEER_ESTABL_CONTACT_EVT:
1407 			state = SELF_UP_PEER_UP;
1408 			break;
1409 		case SELF_LOST_CONTACT_EVT:
1410 			state = SELF_DOWN_PEER_DOWN;
1411 			break;
1412 		case SELF_ESTABL_CONTACT_EVT:
1413 		case PEER_LOST_CONTACT_EVT:
1414 		case NODE_SYNCH_END_EVT:
1415 		case NODE_FAILOVER_BEGIN_EVT:
1416 			break;
1417 		case NODE_SYNCH_BEGIN_EVT:
1418 		case NODE_FAILOVER_END_EVT:
1419 		default:
1420 			goto illegal_evt;
1421 		}
1422 		break;
1423 	case SELF_COMING_PEER_UP:
1424 		switch (evt) {
1425 		case SELF_ESTABL_CONTACT_EVT:
1426 			state = SELF_UP_PEER_UP;
1427 			break;
1428 		case PEER_LOST_CONTACT_EVT:
1429 			state = SELF_DOWN_PEER_DOWN;
1430 			break;
1431 		case SELF_LOST_CONTACT_EVT:
1432 		case PEER_ESTABL_CONTACT_EVT:
1433 			break;
1434 		case NODE_SYNCH_END_EVT:
1435 		case NODE_SYNCH_BEGIN_EVT:
1436 		case NODE_FAILOVER_BEGIN_EVT:
1437 		case NODE_FAILOVER_END_EVT:
1438 		default:
1439 			goto illegal_evt;
1440 		}
1441 		break;
1442 	case SELF_LEAVING_PEER_DOWN:
1443 		switch (evt) {
1444 		case SELF_LOST_CONTACT_EVT:
1445 			state = SELF_DOWN_PEER_DOWN;
1446 			break;
1447 		case SELF_ESTABL_CONTACT_EVT:
1448 		case PEER_ESTABL_CONTACT_EVT:
1449 		case PEER_LOST_CONTACT_EVT:
1450 			break;
1451 		case NODE_SYNCH_END_EVT:
1452 		case NODE_SYNCH_BEGIN_EVT:
1453 		case NODE_FAILOVER_BEGIN_EVT:
1454 		case NODE_FAILOVER_END_EVT:
1455 		default:
1456 			goto illegal_evt;
1457 		}
1458 		break;
1459 	case NODE_FAILINGOVER:
1460 		switch (evt) {
1461 		case SELF_LOST_CONTACT_EVT:
1462 			state = SELF_DOWN_PEER_LEAVING;
1463 			break;
1464 		case PEER_LOST_CONTACT_EVT:
1465 			state = SELF_LEAVING_PEER_DOWN;
1466 			break;
1467 		case NODE_FAILOVER_END_EVT:
1468 			state = SELF_UP_PEER_UP;
1469 			break;
1470 		case NODE_FAILOVER_BEGIN_EVT:
1471 		case SELF_ESTABL_CONTACT_EVT:
1472 		case PEER_ESTABL_CONTACT_EVT:
1473 			break;
1474 		case NODE_SYNCH_BEGIN_EVT:
1475 		case NODE_SYNCH_END_EVT:
1476 		default:
1477 			goto illegal_evt;
1478 		}
1479 		break;
1480 	case NODE_SYNCHING:
1481 		switch (evt) {
1482 		case SELF_LOST_CONTACT_EVT:
1483 			state = SELF_DOWN_PEER_LEAVING;
1484 			break;
1485 		case PEER_LOST_CONTACT_EVT:
1486 			state = SELF_LEAVING_PEER_DOWN;
1487 			break;
1488 		case NODE_SYNCH_END_EVT:
1489 			state = SELF_UP_PEER_UP;
1490 			break;
1491 		case NODE_FAILOVER_BEGIN_EVT:
1492 			state = NODE_FAILINGOVER;
1493 			break;
1494 		case NODE_SYNCH_BEGIN_EVT:
1495 		case SELF_ESTABL_CONTACT_EVT:
1496 		case PEER_ESTABL_CONTACT_EVT:
1497 			break;
1498 		case NODE_FAILOVER_END_EVT:
1499 		default:
1500 			goto illegal_evt;
1501 		}
1502 		break;
1503 	default:
1504 		pr_err("Unknown node fsm state %x\n", state);
1505 		break;
1506 	}
1507 	trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
1508 	n->state = state;
1509 	return;
1510 
1511 illegal_evt:
1512 	pr_err("Illegal node fsm evt %x in state %x\n", evt, state);
1513 	trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
1514 }
1515 
1516 static void node_lost_contact(struct tipc_node *n,
1517 			      struct sk_buff_head *inputq)
1518 {
1519 	struct tipc_sock_conn *conn, *safe;
1520 	struct tipc_link *l;
1521 	struct list_head *conns = &n->conn_sks;
1522 	struct sk_buff *skb;
1523 	uint i;
1524 
1525 	pr_debug("Lost contact with %x\n", n->addr);
1526 	n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
1527 	trace_tipc_node_lost_contact(n, true, " ");
1528 
1529 	/* Clean up broadcast state */
1530 	tipc_bcast_remove_peer(n->net, n->bc_entry.link);
1531 	skb_queue_purge(&n->bc_entry.namedq);
1532 
1533 	/* Abort any ongoing link failover */
1534 	for (i = 0; i < MAX_BEARERS; i++) {
1535 		l = n->links[i].link;
1536 		if (l)
1537 			tipc_link_fsm_evt(l, LINK_FAILOVER_END_EVT);
1538 	}
1539 
1540 	/* Notify publications from this node */
1541 	n->action_flags |= TIPC_NOTIFY_NODE_DOWN;
1542 	n->peer_net = NULL;
1543 	n->peer_hash_mix = 0;
1544 	/* Notify sockets connected to node */
1545 	list_for_each_entry_safe(conn, safe, conns, list) {
1546 		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_CONN_MSG,
1547 				      SHORT_H_SIZE, 0, tipc_own_addr(n->net),
1548 				      conn->peer_node, conn->port,
1549 				      conn->peer_port, TIPC_ERR_NO_NODE);
1550 		if (likely(skb))
1551 			skb_queue_tail(inputq, skb);
1552 		list_del(&conn->list);
1553 		kfree(conn);
1554 	}
1555 }
1556 
1557 /**
1558  * tipc_node_get_linkname - get the name of a link
1559  *
1560  * @net: the applicable net namespace
1561  * @bearer_id: id of the bearer
1562  * @addr: peer node address
1563  * @linkname: link name output buffer
1564  * @len: size of @linkname output buffer
1565  *
1566  * Return: 0 on success
1567  */
1568 int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 addr,
1569 			   char *linkname, size_t len)
1570 {
1571 	struct tipc_link *link;
1572 	int err = -EINVAL;
1573 	struct tipc_node *node = tipc_node_find(net, addr);
1574 
1575 	if (!node)
1576 		return err;
1577 
1578 	if (bearer_id >= MAX_BEARERS)
1579 		goto exit;
1580 
1581 	tipc_node_read_lock(node);
1582 	link = node->links[bearer_id].link;
1583 	if (link) {
1584 		strncpy(linkname, tipc_link_name(link), len);
1585 		err = 0;
1586 	}
1587 	tipc_node_read_unlock(node);
1588 exit:
1589 	tipc_node_put(node);
1590 	return err;
1591 }
1592 
1593 /* Caller should hold node lock for the passed node */
1594 static int __tipc_nl_add_node(struct tipc_nl_msg *msg, struct tipc_node *node)
1595 {
1596 	void *hdr;
1597 	struct nlattr *attrs;
1598 
1599 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1600 			  NLM_F_MULTI, TIPC_NL_NODE_GET);
1601 	if (!hdr)
1602 		return -EMSGSIZE;
1603 
1604 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NODE);
1605 	if (!attrs)
1606 		goto msg_full;
1607 
1608 	if (nla_put_u32(msg->skb, TIPC_NLA_NODE_ADDR, node->addr))
1609 		goto attr_msg_full;
1610 	if (node_is_up(node))
1611 		if (nla_put_flag(msg->skb, TIPC_NLA_NODE_UP))
1612 			goto attr_msg_full;
1613 
1614 	nla_nest_end(msg->skb, attrs);
1615 	genlmsg_end(msg->skb, hdr);
1616 
1617 	return 0;
1618 
1619 attr_msg_full:
1620 	nla_nest_cancel(msg->skb, attrs);
1621 msg_full:
1622 	genlmsg_cancel(msg->skb, hdr);
1623 
1624 	return -EMSGSIZE;
1625 }
1626 
1627 static void tipc_lxc_xmit(struct net *peer_net, struct sk_buff_head *list)
1628 {
1629 	struct tipc_msg *hdr = buf_msg(skb_peek(list));
1630 	struct sk_buff_head inputq;
1631 
1632 	switch (msg_user(hdr)) {
1633 	case TIPC_LOW_IMPORTANCE:
1634 	case TIPC_MEDIUM_IMPORTANCE:
1635 	case TIPC_HIGH_IMPORTANCE:
1636 	case TIPC_CRITICAL_IMPORTANCE:
1637 		if (msg_connected(hdr) || msg_named(hdr) ||
1638 		    msg_direct(hdr)) {
1639 			tipc_loopback_trace(peer_net, list);
1640 			spin_lock_init(&list->lock);
1641 			tipc_sk_rcv(peer_net, list);
1642 			return;
1643 		}
1644 		if (msg_mcast(hdr)) {
1645 			tipc_loopback_trace(peer_net, list);
1646 			skb_queue_head_init(&inputq);
1647 			tipc_sk_mcast_rcv(peer_net, list, &inputq);
1648 			__skb_queue_purge(list);
1649 			skb_queue_purge(&inputq);
1650 			return;
1651 		}
1652 		return;
1653 	case MSG_FRAGMENTER:
1654 		if (tipc_msg_assemble(list)) {
1655 			tipc_loopback_trace(peer_net, list);
1656 			skb_queue_head_init(&inputq);
1657 			tipc_sk_mcast_rcv(peer_net, list, &inputq);
1658 			__skb_queue_purge(list);
1659 			skb_queue_purge(&inputq);
1660 		}
1661 		return;
1662 	case GROUP_PROTOCOL:
1663 	case CONN_MANAGER:
1664 		tipc_loopback_trace(peer_net, list);
1665 		spin_lock_init(&list->lock);
1666 		tipc_sk_rcv(peer_net, list);
1667 		return;
1668 	case LINK_PROTOCOL:
1669 	case NAME_DISTRIBUTOR:
1670 	case TUNNEL_PROTOCOL:
1671 	case BCAST_PROTOCOL:
1672 		return;
1673 	default:
1674 		return;
1675 	}
1676 }
1677 
1678 /**
1679  * tipc_node_xmit() - general link level function for message sending
1680  * @net: the applicable net namespace
1681  * @list: chain of buffers containing message
1682  * @dnode: address of destination node
1683  * @selector: a number used for deterministic link selection
1684  * Consumes the buffer chain.
1685  * Return: 0 if success, otherwise: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE,-ENOBUF
1686  */
1687 int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
1688 		   u32 dnode, int selector)
1689 {
1690 	struct tipc_link_entry *le = NULL;
1691 	struct tipc_node *n;
1692 	struct sk_buff_head xmitq;
1693 	bool node_up = false;
1694 	struct net *peer_net;
1695 	int bearer_id;
1696 	int rc;
1697 
1698 	if (in_own_node(net, dnode)) {
1699 		tipc_loopback_trace(net, list);
1700 		spin_lock_init(&list->lock);
1701 		tipc_sk_rcv(net, list);
1702 		return 0;
1703 	}
1704 
1705 	n = tipc_node_find(net, dnode);
1706 	if (unlikely(!n)) {
1707 		__skb_queue_purge(list);
1708 		return -EHOSTUNREACH;
1709 	}
1710 
1711 	rcu_read_lock();
1712 	tipc_node_read_lock(n);
1713 	node_up = node_is_up(n);
1714 	peer_net = n->peer_net;
1715 	tipc_node_read_unlock(n);
1716 	if (node_up && peer_net && check_net(peer_net)) {
1717 		/* xmit inner linux container */
1718 		tipc_lxc_xmit(peer_net, list);
1719 		if (likely(skb_queue_empty(list))) {
1720 			rcu_read_unlock();
1721 			tipc_node_put(n);
1722 			return 0;
1723 		}
1724 	}
1725 	rcu_read_unlock();
1726 
1727 	tipc_node_read_lock(n);
1728 	bearer_id = n->active_links[selector & 1];
1729 	if (unlikely(bearer_id == INVALID_BEARER_ID)) {
1730 		tipc_node_read_unlock(n);
1731 		tipc_node_put(n);
1732 		__skb_queue_purge(list);
1733 		return -EHOSTUNREACH;
1734 	}
1735 
1736 	__skb_queue_head_init(&xmitq);
1737 	le = &n->links[bearer_id];
1738 	spin_lock_bh(&le->lock);
1739 	rc = tipc_link_xmit(le->link, list, &xmitq);
1740 	spin_unlock_bh(&le->lock);
1741 	tipc_node_read_unlock(n);
1742 
1743 	if (unlikely(rc == -ENOBUFS))
1744 		tipc_node_link_down(n, bearer_id, false);
1745 	else
1746 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
1747 
1748 	tipc_node_put(n);
1749 
1750 	return rc;
1751 }
1752 
1753 /* tipc_node_xmit_skb(): send single buffer to destination
1754  * Buffers sent via this function are generally TIPC_SYSTEM_IMPORTANCE
1755  * messages, which will not be rejected
1756  * The only exception is datagram messages rerouted after secondary
1757  * lookup, which are rare and safe to dispose of anyway.
1758  */
1759 int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode,
1760 		       u32 selector)
1761 {
1762 	struct sk_buff_head head;
1763 
1764 	__skb_queue_head_init(&head);
1765 	__skb_queue_tail(&head, skb);
1766 	tipc_node_xmit(net, &head, dnode, selector);
1767 	return 0;
1768 }
1769 
1770 /* tipc_node_distr_xmit(): send single buffer msgs to individual destinations
1771  * Note: this is only for SYSTEM_IMPORTANCE messages, which cannot be rejected
1772  */
1773 int tipc_node_distr_xmit(struct net *net, struct sk_buff_head *xmitq)
1774 {
1775 	struct sk_buff *skb;
1776 	u32 selector, dnode;
1777 
1778 	while ((skb = __skb_dequeue(xmitq))) {
1779 		selector = msg_origport(buf_msg(skb));
1780 		dnode = msg_destnode(buf_msg(skb));
1781 		tipc_node_xmit_skb(net, skb, dnode, selector);
1782 	}
1783 	return 0;
1784 }
1785 
1786 void tipc_node_broadcast(struct net *net, struct sk_buff *skb, int rc_dests)
1787 {
1788 	struct sk_buff_head xmitq;
1789 	struct sk_buff *txskb;
1790 	struct tipc_node *n;
1791 	u16 dummy;
1792 	u32 dst;
1793 
1794 	/* Use broadcast if all nodes support it */
1795 	if (!rc_dests && tipc_bcast_get_mode(net) != BCLINK_MODE_RCAST) {
1796 		__skb_queue_head_init(&xmitq);
1797 		__skb_queue_tail(&xmitq, skb);
1798 		tipc_bcast_xmit(net, &xmitq, &dummy);
1799 		return;
1800 	}
1801 
1802 	/* Otherwise use legacy replicast method */
1803 	rcu_read_lock();
1804 	list_for_each_entry_rcu(n, tipc_nodes(net), list) {
1805 		dst = n->addr;
1806 		if (in_own_node(net, dst))
1807 			continue;
1808 		if (!node_is_up(n))
1809 			continue;
1810 		txskb = pskb_copy(skb, GFP_ATOMIC);
1811 		if (!txskb)
1812 			break;
1813 		msg_set_destnode(buf_msg(txskb), dst);
1814 		tipc_node_xmit_skb(net, txskb, dst, 0);
1815 	}
1816 	rcu_read_unlock();
1817 	kfree_skb(skb);
1818 }
1819 
1820 static void tipc_node_mcast_rcv(struct tipc_node *n)
1821 {
1822 	struct tipc_bclink_entry *be = &n->bc_entry;
1823 
1824 	/* 'arrvq' is under inputq2's lock protection */
1825 	spin_lock_bh(&be->inputq2.lock);
1826 	spin_lock_bh(&be->inputq1.lock);
1827 	skb_queue_splice_tail_init(&be->inputq1, &be->arrvq);
1828 	spin_unlock_bh(&be->inputq1.lock);
1829 	spin_unlock_bh(&be->inputq2.lock);
1830 	tipc_sk_mcast_rcv(n->net, &be->arrvq, &be->inputq2);
1831 }
1832 
1833 static void tipc_node_bc_sync_rcv(struct tipc_node *n, struct tipc_msg *hdr,
1834 				  int bearer_id, struct sk_buff_head *xmitq)
1835 {
1836 	struct tipc_link *ucl;
1837 	int rc;
1838 
1839 	rc = tipc_bcast_sync_rcv(n->net, n->bc_entry.link, hdr, xmitq);
1840 
1841 	if (rc & TIPC_LINK_DOWN_EVT) {
1842 		tipc_node_reset_links(n);
1843 		return;
1844 	}
1845 
1846 	if (!(rc & TIPC_LINK_SND_STATE))
1847 		return;
1848 
1849 	/* If probe message, a STATE response will be sent anyway */
1850 	if (msg_probe(hdr))
1851 		return;
1852 
1853 	/* Produce a STATE message carrying broadcast NACK */
1854 	tipc_node_read_lock(n);
1855 	ucl = n->links[bearer_id].link;
1856 	if (ucl)
1857 		tipc_link_build_state_msg(ucl, xmitq);
1858 	tipc_node_read_unlock(n);
1859 }
1860 
1861 /**
1862  * tipc_node_bc_rcv - process TIPC broadcast packet arriving from off-node
1863  * @net: the applicable net namespace
1864  * @skb: TIPC packet
1865  * @bearer_id: id of bearer message arrived on
1866  *
1867  * Invoked with no locks held.
1868  */
1869 static void tipc_node_bc_rcv(struct net *net, struct sk_buff *skb, int bearer_id)
1870 {
1871 	int rc;
1872 	struct sk_buff_head xmitq;
1873 	struct tipc_bclink_entry *be;
1874 	struct tipc_link_entry *le;
1875 	struct tipc_msg *hdr = buf_msg(skb);
1876 	int usr = msg_user(hdr);
1877 	u32 dnode = msg_destnode(hdr);
1878 	struct tipc_node *n;
1879 
1880 	__skb_queue_head_init(&xmitq);
1881 
1882 	/* If NACK for other node, let rcv link for that node peek into it */
1883 	if ((usr == BCAST_PROTOCOL) && (dnode != tipc_own_addr(net)))
1884 		n = tipc_node_find(net, dnode);
1885 	else
1886 		n = tipc_node_find(net, msg_prevnode(hdr));
1887 	if (!n) {
1888 		kfree_skb(skb);
1889 		return;
1890 	}
1891 	be = &n->bc_entry;
1892 	le = &n->links[bearer_id];
1893 
1894 	rc = tipc_bcast_rcv(net, be->link, skb);
1895 
1896 	/* Broadcast ACKs are sent on a unicast link */
1897 	if (rc & TIPC_LINK_SND_STATE) {
1898 		tipc_node_read_lock(n);
1899 		tipc_link_build_state_msg(le->link, &xmitq);
1900 		tipc_node_read_unlock(n);
1901 	}
1902 
1903 	if (!skb_queue_empty(&xmitq))
1904 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
1905 
1906 	if (!skb_queue_empty(&be->inputq1))
1907 		tipc_node_mcast_rcv(n);
1908 
1909 	/* Handle NAME_DISTRIBUTOR messages sent from 1.7 nodes */
1910 	if (!skb_queue_empty(&n->bc_entry.namedq))
1911 		tipc_named_rcv(net, &n->bc_entry.namedq,
1912 			       &n->bc_entry.named_rcv_nxt,
1913 			       &n->bc_entry.named_open);
1914 
1915 	/* If reassembly or retransmission failure => reset all links to peer */
1916 	if (rc & TIPC_LINK_DOWN_EVT)
1917 		tipc_node_reset_links(n);
1918 
1919 	tipc_node_put(n);
1920 }
1921 
1922 /**
1923  * tipc_node_check_state - check and if necessary update node state
1924  * @n: target tipc_node
1925  * @skb: TIPC packet
1926  * @bearer_id: identity of bearer delivering the packet
1927  * @xmitq: queue for messages to be xmited on
1928  * Return: true if state and msg are ok, otherwise false
1929  */
1930 static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
1931 				  int bearer_id, struct sk_buff_head *xmitq)
1932 {
1933 	struct tipc_msg *hdr = buf_msg(skb);
1934 	int usr = msg_user(hdr);
1935 	int mtyp = msg_type(hdr);
1936 	u16 oseqno = msg_seqno(hdr);
1937 	u16 exp_pkts = msg_msgcnt(hdr);
1938 	u16 rcv_nxt, syncpt, dlv_nxt, inputq_len;
1939 	int state = n->state;
1940 	struct tipc_link *l, *tnl, *pl = NULL;
1941 	struct tipc_media_addr *maddr;
1942 	int pb_id;
1943 
1944 	if (trace_tipc_node_check_state_enabled()) {
1945 		trace_tipc_skb_dump(skb, false, "skb for node state check");
1946 		trace_tipc_node_check_state(n, true, " ");
1947 	}
1948 	l = n->links[bearer_id].link;
1949 	if (!l)
1950 		return false;
1951 	rcv_nxt = tipc_link_rcv_nxt(l);
1952 
1953 
1954 	if (likely((state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL)))
1955 		return true;
1956 
1957 	/* Find parallel link, if any */
1958 	for (pb_id = 0; pb_id < MAX_BEARERS; pb_id++) {
1959 		if ((pb_id != bearer_id) && n->links[pb_id].link) {
1960 			pl = n->links[pb_id].link;
1961 			break;
1962 		}
1963 	}
1964 
1965 	if (!tipc_link_validate_msg(l, hdr)) {
1966 		trace_tipc_skb_dump(skb, false, "PROTO invalid (2)!");
1967 		trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (2)!");
1968 		return false;
1969 	}
1970 
1971 	/* Check and update node accesibility if applicable */
1972 	if (state == SELF_UP_PEER_COMING) {
1973 		if (!tipc_link_is_up(l))
1974 			return true;
1975 		if (!msg_peer_link_is_up(hdr))
1976 			return true;
1977 		tipc_node_fsm_evt(n, PEER_ESTABL_CONTACT_EVT);
1978 	}
1979 
1980 	if (state == SELF_DOWN_PEER_LEAVING) {
1981 		if (msg_peer_node_is_up(hdr))
1982 			return false;
1983 		tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
1984 		return true;
1985 	}
1986 
1987 	if (state == SELF_LEAVING_PEER_DOWN)
1988 		return false;
1989 
1990 	/* Ignore duplicate packets */
1991 	if ((usr != LINK_PROTOCOL) && less(oseqno, rcv_nxt))
1992 		return true;
1993 
1994 	/* Initiate or update failover mode if applicable */
1995 	if ((usr == TUNNEL_PROTOCOL) && (mtyp == FAILOVER_MSG)) {
1996 		syncpt = oseqno + exp_pkts - 1;
1997 		if (pl && !tipc_link_is_reset(pl)) {
1998 			__tipc_node_link_down(n, &pb_id, xmitq, &maddr);
1999 			trace_tipc_node_link_down(n, true,
2000 						  "node link down <- failover!");
2001 			tipc_skb_queue_splice_tail_init(tipc_link_inputq(pl),
2002 							tipc_link_inputq(l));
2003 		}
2004 
2005 		/* If parallel link was already down, and this happened before
2006 		 * the tunnel link came up, node failover was never started.
2007 		 * Ensure that a FAILOVER_MSG is sent to get peer out of
2008 		 * NODE_FAILINGOVER state, also this node must accept
2009 		 * TUNNEL_MSGs from peer.
2010 		 */
2011 		if (n->state != NODE_FAILINGOVER)
2012 			tipc_node_link_failover(n, pl, l, xmitq);
2013 
2014 		/* If pkts arrive out of order, use lowest calculated syncpt */
2015 		if (less(syncpt, n->sync_point))
2016 			n->sync_point = syncpt;
2017 	}
2018 
2019 	/* Open parallel link when tunnel link reaches synch point */
2020 	if ((n->state == NODE_FAILINGOVER) && tipc_link_is_up(l)) {
2021 		if (!more(rcv_nxt, n->sync_point))
2022 			return true;
2023 		tipc_node_fsm_evt(n, NODE_FAILOVER_END_EVT);
2024 		if (pl)
2025 			tipc_link_fsm_evt(pl, LINK_FAILOVER_END_EVT);
2026 		return true;
2027 	}
2028 
2029 	/* No syncing needed if only one link */
2030 	if (!pl || !tipc_link_is_up(pl))
2031 		return true;
2032 
2033 	/* Initiate synch mode if applicable */
2034 	if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG) && (oseqno == 1)) {
2035 		if (n->capabilities & TIPC_TUNNEL_ENHANCED)
2036 			syncpt = msg_syncpt(hdr);
2037 		else
2038 			syncpt = msg_seqno(msg_inner_hdr(hdr)) + exp_pkts - 1;
2039 		if (!tipc_link_is_up(l))
2040 			__tipc_node_link_up(n, bearer_id, xmitq);
2041 		if (n->state == SELF_UP_PEER_UP) {
2042 			n->sync_point = syncpt;
2043 			tipc_link_fsm_evt(l, LINK_SYNCH_BEGIN_EVT);
2044 			tipc_node_fsm_evt(n, NODE_SYNCH_BEGIN_EVT);
2045 		}
2046 	}
2047 
2048 	/* Open tunnel link when parallel link reaches synch point */
2049 	if (n->state == NODE_SYNCHING) {
2050 		if (tipc_link_is_synching(l)) {
2051 			tnl = l;
2052 		} else {
2053 			tnl = pl;
2054 			pl = l;
2055 		}
2056 		inputq_len = skb_queue_len(tipc_link_inputq(pl));
2057 		dlv_nxt = tipc_link_rcv_nxt(pl) - inputq_len;
2058 		if (more(dlv_nxt, n->sync_point)) {
2059 			tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
2060 			tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
2061 			return true;
2062 		}
2063 		if (l == pl)
2064 			return true;
2065 		if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG))
2066 			return true;
2067 		if (usr == LINK_PROTOCOL)
2068 			return true;
2069 		return false;
2070 	}
2071 	return true;
2072 }
2073 
2074 /**
2075  * tipc_rcv - process TIPC packets/messages arriving from off-node
2076  * @net: the applicable net namespace
2077  * @skb: TIPC packet
2078  * @b: pointer to bearer message arrived on
2079  *
2080  * Invoked with no locks held. Bearer pointer must point to a valid bearer
2081  * structure (i.e. cannot be NULL), but bearer can be inactive.
2082  */
2083 void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
2084 {
2085 	struct sk_buff_head xmitq;
2086 	struct tipc_link_entry *le;
2087 	struct tipc_msg *hdr;
2088 	struct tipc_node *n;
2089 	int bearer_id = b->identity;
2090 	u32 self = tipc_own_addr(net);
2091 	int usr, rc = 0;
2092 	u16 bc_ack;
2093 #ifdef CONFIG_TIPC_CRYPTO
2094 	struct tipc_ehdr *ehdr;
2095 
2096 	/* Check if message must be decrypted first */
2097 	if (TIPC_SKB_CB(skb)->decrypted || !tipc_ehdr_validate(skb))
2098 		goto rcv;
2099 
2100 	ehdr = (struct tipc_ehdr *)skb->data;
2101 	if (likely(ehdr->user != LINK_CONFIG)) {
2102 		n = tipc_node_find(net, ntohl(ehdr->addr));
2103 		if (unlikely(!n))
2104 			goto discard;
2105 	} else {
2106 		n = tipc_node_find_by_id(net, ehdr->id);
2107 	}
2108 	skb_dst_force(skb);
2109 	tipc_crypto_rcv(net, (n) ? n->crypto_rx : NULL, &skb, b);
2110 	if (!skb)
2111 		return;
2112 
2113 rcv:
2114 #endif
2115 	/* Ensure message is well-formed before touching the header */
2116 	if (unlikely(!tipc_msg_validate(&skb)))
2117 		goto discard;
2118 	__skb_queue_head_init(&xmitq);
2119 	hdr = buf_msg(skb);
2120 	usr = msg_user(hdr);
2121 	bc_ack = msg_bcast_ack(hdr);
2122 
2123 	/* Handle arrival of discovery or broadcast packet */
2124 	if (unlikely(msg_non_seq(hdr))) {
2125 		if (unlikely(usr == LINK_CONFIG))
2126 			return tipc_disc_rcv(net, skb, b);
2127 		else
2128 			return tipc_node_bc_rcv(net, skb, bearer_id);
2129 	}
2130 
2131 	/* Discard unicast link messages destined for another node */
2132 	if (unlikely(!msg_short(hdr) && (msg_destnode(hdr) != self)))
2133 		goto discard;
2134 
2135 	/* Locate neighboring node that sent packet */
2136 	n = tipc_node_find(net, msg_prevnode(hdr));
2137 	if (unlikely(!n))
2138 		goto discard;
2139 	le = &n->links[bearer_id];
2140 
2141 	/* Ensure broadcast reception is in synch with peer's send state */
2142 	if (unlikely(usr == LINK_PROTOCOL)) {
2143 		if (unlikely(skb_linearize(skb))) {
2144 			tipc_node_put(n);
2145 			goto discard;
2146 		}
2147 		hdr = buf_msg(skb);
2148 		tipc_node_bc_sync_rcv(n, hdr, bearer_id, &xmitq);
2149 	} else if (unlikely(tipc_link_acked(n->bc_entry.link) != bc_ack)) {
2150 		tipc_bcast_ack_rcv(net, n->bc_entry.link, hdr);
2151 	}
2152 
2153 	/* Receive packet directly if conditions permit */
2154 	tipc_node_read_lock(n);
2155 	if (likely((n->state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL))) {
2156 		spin_lock_bh(&le->lock);
2157 		if (le->link) {
2158 			rc = tipc_link_rcv(le->link, skb, &xmitq);
2159 			skb = NULL;
2160 		}
2161 		spin_unlock_bh(&le->lock);
2162 	}
2163 	tipc_node_read_unlock(n);
2164 
2165 	/* Check/update node state before receiving */
2166 	if (unlikely(skb)) {
2167 		if (unlikely(skb_linearize(skb)))
2168 			goto out_node_put;
2169 		tipc_node_write_lock(n);
2170 		if (tipc_node_check_state(n, skb, bearer_id, &xmitq)) {
2171 			if (le->link) {
2172 				rc = tipc_link_rcv(le->link, skb, &xmitq);
2173 				skb = NULL;
2174 			}
2175 		}
2176 		tipc_node_write_unlock(n);
2177 	}
2178 
2179 	if (unlikely(rc & TIPC_LINK_UP_EVT))
2180 		tipc_node_link_up(n, bearer_id, &xmitq);
2181 
2182 	if (unlikely(rc & TIPC_LINK_DOWN_EVT))
2183 		tipc_node_link_down(n, bearer_id, false);
2184 
2185 	if (unlikely(!skb_queue_empty(&n->bc_entry.namedq)))
2186 		tipc_named_rcv(net, &n->bc_entry.namedq,
2187 			       &n->bc_entry.named_rcv_nxt,
2188 			       &n->bc_entry.named_open);
2189 
2190 	if (unlikely(!skb_queue_empty(&n->bc_entry.inputq1)))
2191 		tipc_node_mcast_rcv(n);
2192 
2193 	if (!skb_queue_empty(&le->inputq))
2194 		tipc_sk_rcv(net, &le->inputq);
2195 
2196 	if (!skb_queue_empty(&xmitq))
2197 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
2198 
2199 out_node_put:
2200 	tipc_node_put(n);
2201 discard:
2202 	kfree_skb(skb);
2203 }
2204 
2205 void tipc_node_apply_property(struct net *net, struct tipc_bearer *b,
2206 			      int prop)
2207 {
2208 	struct tipc_net *tn = tipc_net(net);
2209 	int bearer_id = b->identity;
2210 	struct sk_buff_head xmitq;
2211 	struct tipc_link_entry *e;
2212 	struct tipc_node *n;
2213 
2214 	__skb_queue_head_init(&xmitq);
2215 
2216 	rcu_read_lock();
2217 
2218 	list_for_each_entry_rcu(n, &tn->node_list, list) {
2219 		tipc_node_write_lock(n);
2220 		e = &n->links[bearer_id];
2221 		if (e->link) {
2222 			if (prop == TIPC_NLA_PROP_TOL)
2223 				tipc_link_set_tolerance(e->link, b->tolerance,
2224 							&xmitq);
2225 			else if (prop == TIPC_NLA_PROP_MTU)
2226 				tipc_link_set_mtu(e->link, b->mtu);
2227 
2228 			/* Update MTU for node link entry */
2229 			e->mtu = tipc_link_mss(e->link);
2230 		}
2231 
2232 		tipc_node_write_unlock(n);
2233 		tipc_bearer_xmit(net, bearer_id, &xmitq, &e->maddr, NULL);
2234 	}
2235 
2236 	rcu_read_unlock();
2237 }
2238 
2239 int tipc_nl_peer_rm(struct sk_buff *skb, struct genl_info *info)
2240 {
2241 	struct net *net = sock_net(skb->sk);
2242 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2243 	struct nlattr *attrs[TIPC_NLA_NET_MAX + 1];
2244 	struct tipc_node *peer, *temp_node;
2245 	u8 node_id[NODE_ID_LEN];
2246 	u64 *w0 = (u64 *)&node_id[0];
2247 	u64 *w1 = (u64 *)&node_id[8];
2248 	u32 addr;
2249 	int err;
2250 
2251 	/* We identify the peer by its net */
2252 	if (!info->attrs[TIPC_NLA_NET])
2253 		return -EINVAL;
2254 
2255 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_NET_MAX,
2256 					  info->attrs[TIPC_NLA_NET],
2257 					  tipc_nl_net_policy, info->extack);
2258 	if (err)
2259 		return err;
2260 
2261 	/* attrs[TIPC_NLA_NET_NODEID] and attrs[TIPC_NLA_NET_ADDR] are
2262 	 * mutually exclusive cases
2263 	 */
2264 	if (attrs[TIPC_NLA_NET_ADDR]) {
2265 		addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]);
2266 		if (!addr)
2267 			return -EINVAL;
2268 	}
2269 
2270 	if (attrs[TIPC_NLA_NET_NODEID]) {
2271 		if (!attrs[TIPC_NLA_NET_NODEID_W1])
2272 			return -EINVAL;
2273 		*w0 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID]);
2274 		*w1 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID_W1]);
2275 		addr = hash128to32(node_id);
2276 	}
2277 
2278 	if (in_own_node(net, addr))
2279 		return -ENOTSUPP;
2280 
2281 	spin_lock_bh(&tn->node_list_lock);
2282 	peer = tipc_node_find(net, addr);
2283 	if (!peer) {
2284 		spin_unlock_bh(&tn->node_list_lock);
2285 		return -ENXIO;
2286 	}
2287 
2288 	tipc_node_write_lock(peer);
2289 	if (peer->state != SELF_DOWN_PEER_DOWN &&
2290 	    peer->state != SELF_DOWN_PEER_LEAVING) {
2291 		tipc_node_write_unlock(peer);
2292 		err = -EBUSY;
2293 		goto err_out;
2294 	}
2295 
2296 	tipc_node_clear_links(peer);
2297 	tipc_node_write_unlock(peer);
2298 	tipc_node_delete(peer);
2299 
2300 	/* Calculate cluster capabilities */
2301 	tn->capabilities = TIPC_NODE_CAPABILITIES;
2302 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
2303 		tn->capabilities &= temp_node->capabilities;
2304 	}
2305 	tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
2306 	err = 0;
2307 err_out:
2308 	tipc_node_put(peer);
2309 	spin_unlock_bh(&tn->node_list_lock);
2310 
2311 	return err;
2312 }
2313 
2314 int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb)
2315 {
2316 	int err;
2317 	struct net *net = sock_net(skb->sk);
2318 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2319 	int done = cb->args[0];
2320 	int last_addr = cb->args[1];
2321 	struct tipc_node *node;
2322 	struct tipc_nl_msg msg;
2323 
2324 	if (done)
2325 		return 0;
2326 
2327 	msg.skb = skb;
2328 	msg.portid = NETLINK_CB(cb->skb).portid;
2329 	msg.seq = cb->nlh->nlmsg_seq;
2330 
2331 	rcu_read_lock();
2332 	if (last_addr) {
2333 		node = tipc_node_find(net, last_addr);
2334 		if (!node) {
2335 			rcu_read_unlock();
2336 			/* We never set seq or call nl_dump_check_consistent()
2337 			 * this means that setting prev_seq here will cause the
2338 			 * consistence check to fail in the netlink callback
2339 			 * handler. Resulting in the NLMSG_DONE message having
2340 			 * the NLM_F_DUMP_INTR flag set if the node state
2341 			 * changed while we released the lock.
2342 			 */
2343 			cb->prev_seq = 1;
2344 			return -EPIPE;
2345 		}
2346 		tipc_node_put(node);
2347 	}
2348 
2349 	list_for_each_entry_rcu(node, &tn->node_list, list) {
2350 		if (node->preliminary)
2351 			continue;
2352 		if (last_addr) {
2353 			if (node->addr == last_addr)
2354 				last_addr = 0;
2355 			else
2356 				continue;
2357 		}
2358 
2359 		tipc_node_read_lock(node);
2360 		err = __tipc_nl_add_node(&msg, node);
2361 		if (err) {
2362 			last_addr = node->addr;
2363 			tipc_node_read_unlock(node);
2364 			goto out;
2365 		}
2366 
2367 		tipc_node_read_unlock(node);
2368 	}
2369 	done = 1;
2370 out:
2371 	cb->args[0] = done;
2372 	cb->args[1] = last_addr;
2373 	rcu_read_unlock();
2374 
2375 	return skb->len;
2376 }
2377 
2378 /* tipc_node_find_by_name - locate owner node of link by link's name
2379  * @net: the applicable net namespace
2380  * @name: pointer to link name string
2381  * @bearer_id: pointer to index in 'node->links' array where the link was found.
2382  *
2383  * Returns pointer to node owning the link, or 0 if no matching link is found.
2384  */
2385 static struct tipc_node *tipc_node_find_by_name(struct net *net,
2386 						const char *link_name,
2387 						unsigned int *bearer_id)
2388 {
2389 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2390 	struct tipc_link *l;
2391 	struct tipc_node *n;
2392 	struct tipc_node *found_node = NULL;
2393 	int i;
2394 
2395 	*bearer_id = 0;
2396 	rcu_read_lock();
2397 	list_for_each_entry_rcu(n, &tn->node_list, list) {
2398 		tipc_node_read_lock(n);
2399 		for (i = 0; i < MAX_BEARERS; i++) {
2400 			l = n->links[i].link;
2401 			if (l && !strcmp(tipc_link_name(l), link_name)) {
2402 				*bearer_id = i;
2403 				found_node = n;
2404 				break;
2405 			}
2406 		}
2407 		tipc_node_read_unlock(n);
2408 		if (found_node)
2409 			break;
2410 	}
2411 	rcu_read_unlock();
2412 
2413 	return found_node;
2414 }
2415 
2416 int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info)
2417 {
2418 	int err;
2419 	int res = 0;
2420 	int bearer_id;
2421 	char *name;
2422 	struct tipc_link *link;
2423 	struct tipc_node *node;
2424 	struct sk_buff_head xmitq;
2425 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2426 	struct net *net = sock_net(skb->sk);
2427 
2428 	__skb_queue_head_init(&xmitq);
2429 
2430 	if (!info->attrs[TIPC_NLA_LINK])
2431 		return -EINVAL;
2432 
2433 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2434 					  info->attrs[TIPC_NLA_LINK],
2435 					  tipc_nl_link_policy, info->extack);
2436 	if (err)
2437 		return err;
2438 
2439 	if (!attrs[TIPC_NLA_LINK_NAME])
2440 		return -EINVAL;
2441 
2442 	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2443 
2444 	if (strcmp(name, tipc_bclink_name) == 0)
2445 		return tipc_nl_bc_link_set(net, attrs);
2446 
2447 	node = tipc_node_find_by_name(net, name, &bearer_id);
2448 	if (!node)
2449 		return -EINVAL;
2450 
2451 	tipc_node_read_lock(node);
2452 
2453 	link = node->links[bearer_id].link;
2454 	if (!link) {
2455 		res = -EINVAL;
2456 		goto out;
2457 	}
2458 
2459 	if (attrs[TIPC_NLA_LINK_PROP]) {
2460 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
2461 
2462 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP], props);
2463 		if (err) {
2464 			res = err;
2465 			goto out;
2466 		}
2467 
2468 		if (props[TIPC_NLA_PROP_TOL]) {
2469 			u32 tol;
2470 
2471 			tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2472 			tipc_link_set_tolerance(link, tol, &xmitq);
2473 		}
2474 		if (props[TIPC_NLA_PROP_PRIO]) {
2475 			u32 prio;
2476 
2477 			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2478 			tipc_link_set_prio(link, prio, &xmitq);
2479 		}
2480 		if (props[TIPC_NLA_PROP_WIN]) {
2481 			u32 max_win;
2482 
2483 			max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2484 			tipc_link_set_queue_limits(link,
2485 						   tipc_link_min_win(link),
2486 						   max_win);
2487 		}
2488 	}
2489 
2490 out:
2491 	tipc_node_read_unlock(node);
2492 	tipc_bearer_xmit(net, bearer_id, &xmitq, &node->links[bearer_id].maddr,
2493 			 NULL);
2494 	return res;
2495 }
2496 
2497 int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info)
2498 {
2499 	struct net *net = genl_info_net(info);
2500 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2501 	struct tipc_nl_msg msg;
2502 	char *name;
2503 	int err;
2504 
2505 	msg.portid = info->snd_portid;
2506 	msg.seq = info->snd_seq;
2507 
2508 	if (!info->attrs[TIPC_NLA_LINK])
2509 		return -EINVAL;
2510 
2511 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2512 					  info->attrs[TIPC_NLA_LINK],
2513 					  tipc_nl_link_policy, info->extack);
2514 	if (err)
2515 		return err;
2516 
2517 	if (!attrs[TIPC_NLA_LINK_NAME])
2518 		return -EINVAL;
2519 
2520 	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2521 
2522 	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2523 	if (!msg.skb)
2524 		return -ENOMEM;
2525 
2526 	if (strcmp(name, tipc_bclink_name) == 0) {
2527 		err = tipc_nl_add_bc_link(net, &msg, tipc_net(net)->bcl);
2528 		if (err)
2529 			goto err_free;
2530 	} else {
2531 		int bearer_id;
2532 		struct tipc_node *node;
2533 		struct tipc_link *link;
2534 
2535 		node = tipc_node_find_by_name(net, name, &bearer_id);
2536 		if (!node) {
2537 			err = -EINVAL;
2538 			goto err_free;
2539 		}
2540 
2541 		tipc_node_read_lock(node);
2542 		link = node->links[bearer_id].link;
2543 		if (!link) {
2544 			tipc_node_read_unlock(node);
2545 			err = -EINVAL;
2546 			goto err_free;
2547 		}
2548 
2549 		err = __tipc_nl_add_link(net, &msg, link, 0);
2550 		tipc_node_read_unlock(node);
2551 		if (err)
2552 			goto err_free;
2553 	}
2554 
2555 	return genlmsg_reply(msg.skb, info);
2556 
2557 err_free:
2558 	nlmsg_free(msg.skb);
2559 	return err;
2560 }
2561 
2562 int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info)
2563 {
2564 	int err;
2565 	char *link_name;
2566 	unsigned int bearer_id;
2567 	struct tipc_link *link;
2568 	struct tipc_node *node;
2569 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2570 	struct net *net = sock_net(skb->sk);
2571 	struct tipc_net *tn = tipc_net(net);
2572 	struct tipc_link_entry *le;
2573 
2574 	if (!info->attrs[TIPC_NLA_LINK])
2575 		return -EINVAL;
2576 
2577 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2578 					  info->attrs[TIPC_NLA_LINK],
2579 					  tipc_nl_link_policy, info->extack);
2580 	if (err)
2581 		return err;
2582 
2583 	if (!attrs[TIPC_NLA_LINK_NAME])
2584 		return -EINVAL;
2585 
2586 	link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2587 
2588 	err = -EINVAL;
2589 	if (!strcmp(link_name, tipc_bclink_name)) {
2590 		err = tipc_bclink_reset_stats(net, tipc_bc_sndlink(net));
2591 		if (err)
2592 			return err;
2593 		return 0;
2594 	} else if (strstr(link_name, tipc_bclink_name)) {
2595 		rcu_read_lock();
2596 		list_for_each_entry_rcu(node, &tn->node_list, list) {
2597 			tipc_node_read_lock(node);
2598 			link = node->bc_entry.link;
2599 			if (link && !strcmp(link_name, tipc_link_name(link))) {
2600 				err = tipc_bclink_reset_stats(net, link);
2601 				tipc_node_read_unlock(node);
2602 				break;
2603 			}
2604 			tipc_node_read_unlock(node);
2605 		}
2606 		rcu_read_unlock();
2607 		return err;
2608 	}
2609 
2610 	node = tipc_node_find_by_name(net, link_name, &bearer_id);
2611 	if (!node)
2612 		return -EINVAL;
2613 
2614 	le = &node->links[bearer_id];
2615 	tipc_node_read_lock(node);
2616 	spin_lock_bh(&le->lock);
2617 	link = node->links[bearer_id].link;
2618 	if (!link) {
2619 		spin_unlock_bh(&le->lock);
2620 		tipc_node_read_unlock(node);
2621 		return -EINVAL;
2622 	}
2623 	tipc_link_reset_stats(link);
2624 	spin_unlock_bh(&le->lock);
2625 	tipc_node_read_unlock(node);
2626 	return 0;
2627 }
2628 
2629 /* Caller should hold node lock  */
2630 static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
2631 				    struct tipc_node *node, u32 *prev_link,
2632 				    bool bc_link)
2633 {
2634 	u32 i;
2635 	int err;
2636 
2637 	for (i = *prev_link; i < MAX_BEARERS; i++) {
2638 		*prev_link = i;
2639 
2640 		if (!node->links[i].link)
2641 			continue;
2642 
2643 		err = __tipc_nl_add_link(net, msg,
2644 					 node->links[i].link, NLM_F_MULTI);
2645 		if (err)
2646 			return err;
2647 	}
2648 
2649 	if (bc_link) {
2650 		*prev_link = i;
2651 		err = tipc_nl_add_bc_link(net, msg, node->bc_entry.link);
2652 		if (err)
2653 			return err;
2654 	}
2655 
2656 	*prev_link = 0;
2657 
2658 	return 0;
2659 }
2660 
2661 int tipc_nl_node_dump_link(struct sk_buff *skb, struct netlink_callback *cb)
2662 {
2663 	struct net *net = sock_net(skb->sk);
2664 	struct nlattr **attrs = genl_dumpit_info(cb)->info.attrs;
2665 	struct nlattr *link[TIPC_NLA_LINK_MAX + 1];
2666 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2667 	struct tipc_node *node;
2668 	struct tipc_nl_msg msg;
2669 	u32 prev_node = cb->args[0];
2670 	u32 prev_link = cb->args[1];
2671 	int done = cb->args[2];
2672 	bool bc_link = cb->args[3];
2673 	int err;
2674 
2675 	if (done)
2676 		return 0;
2677 
2678 	if (!prev_node) {
2679 		/* Check if broadcast-receiver links dumping is needed */
2680 		if (attrs && attrs[TIPC_NLA_LINK]) {
2681 			err = nla_parse_nested_deprecated(link,
2682 							  TIPC_NLA_LINK_MAX,
2683 							  attrs[TIPC_NLA_LINK],
2684 							  tipc_nl_link_policy,
2685 							  NULL);
2686 			if (unlikely(err))
2687 				return err;
2688 			if (unlikely(!link[TIPC_NLA_LINK_BROADCAST]))
2689 				return -EINVAL;
2690 			bc_link = true;
2691 		}
2692 	}
2693 
2694 	msg.skb = skb;
2695 	msg.portid = NETLINK_CB(cb->skb).portid;
2696 	msg.seq = cb->nlh->nlmsg_seq;
2697 
2698 	rcu_read_lock();
2699 	if (prev_node) {
2700 		node = tipc_node_find(net, prev_node);
2701 		if (!node) {
2702 			/* We never set seq or call nl_dump_check_consistent()
2703 			 * this means that setting prev_seq here will cause the
2704 			 * consistence check to fail in the netlink callback
2705 			 * handler. Resulting in the last NLMSG_DONE message
2706 			 * having the NLM_F_DUMP_INTR flag set.
2707 			 */
2708 			cb->prev_seq = 1;
2709 			goto out;
2710 		}
2711 		tipc_node_put(node);
2712 
2713 		list_for_each_entry_continue_rcu(node, &tn->node_list,
2714 						 list) {
2715 			tipc_node_read_lock(node);
2716 			err = __tipc_nl_add_node_links(net, &msg, node,
2717 						       &prev_link, bc_link);
2718 			tipc_node_read_unlock(node);
2719 			if (err)
2720 				goto out;
2721 
2722 			prev_node = node->addr;
2723 		}
2724 	} else {
2725 		err = tipc_nl_add_bc_link(net, &msg, tn->bcl);
2726 		if (err)
2727 			goto out;
2728 
2729 		list_for_each_entry_rcu(node, &tn->node_list, list) {
2730 			tipc_node_read_lock(node);
2731 			err = __tipc_nl_add_node_links(net, &msg, node,
2732 						       &prev_link, bc_link);
2733 			tipc_node_read_unlock(node);
2734 			if (err)
2735 				goto out;
2736 
2737 			prev_node = node->addr;
2738 		}
2739 	}
2740 	done = 1;
2741 out:
2742 	rcu_read_unlock();
2743 
2744 	cb->args[0] = prev_node;
2745 	cb->args[1] = prev_link;
2746 	cb->args[2] = done;
2747 	cb->args[3] = bc_link;
2748 
2749 	return skb->len;
2750 }
2751 
2752 int tipc_nl_node_set_monitor(struct sk_buff *skb, struct genl_info *info)
2753 {
2754 	struct nlattr *attrs[TIPC_NLA_MON_MAX + 1];
2755 	struct net *net = sock_net(skb->sk);
2756 	int err;
2757 
2758 	if (!info->attrs[TIPC_NLA_MON])
2759 		return -EINVAL;
2760 
2761 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_MON_MAX,
2762 					  info->attrs[TIPC_NLA_MON],
2763 					  tipc_nl_monitor_policy,
2764 					  info->extack);
2765 	if (err)
2766 		return err;
2767 
2768 	if (attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]) {
2769 		u32 val;
2770 
2771 		val = nla_get_u32(attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]);
2772 		err = tipc_nl_monitor_set_threshold(net, val);
2773 		if (err)
2774 			return err;
2775 	}
2776 
2777 	return 0;
2778 }
2779 
2780 static int __tipc_nl_add_monitor_prop(struct net *net, struct tipc_nl_msg *msg)
2781 {
2782 	struct nlattr *attrs;
2783 	void *hdr;
2784 	u32 val;
2785 
2786 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2787 			  0, TIPC_NL_MON_GET);
2788 	if (!hdr)
2789 		return -EMSGSIZE;
2790 
2791 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_MON);
2792 	if (!attrs)
2793 		goto msg_full;
2794 
2795 	val = tipc_nl_monitor_get_threshold(net);
2796 
2797 	if (nla_put_u32(msg->skb, TIPC_NLA_MON_ACTIVATION_THRESHOLD, val))
2798 		goto attr_msg_full;
2799 
2800 	nla_nest_end(msg->skb, attrs);
2801 	genlmsg_end(msg->skb, hdr);
2802 
2803 	return 0;
2804 
2805 attr_msg_full:
2806 	nla_nest_cancel(msg->skb, attrs);
2807 msg_full:
2808 	genlmsg_cancel(msg->skb, hdr);
2809 
2810 	return -EMSGSIZE;
2811 }
2812 
2813 int tipc_nl_node_get_monitor(struct sk_buff *skb, struct genl_info *info)
2814 {
2815 	struct net *net = sock_net(skb->sk);
2816 	struct tipc_nl_msg msg;
2817 	int err;
2818 
2819 	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2820 	if (!msg.skb)
2821 		return -ENOMEM;
2822 	msg.portid = info->snd_portid;
2823 	msg.seq = info->snd_seq;
2824 
2825 	err = __tipc_nl_add_monitor_prop(net, &msg);
2826 	if (err) {
2827 		nlmsg_free(msg.skb);
2828 		return err;
2829 	}
2830 
2831 	return genlmsg_reply(msg.skb, info);
2832 }
2833 
2834 int tipc_nl_node_dump_monitor(struct sk_buff *skb, struct netlink_callback *cb)
2835 {
2836 	struct net *net = sock_net(skb->sk);
2837 	u32 prev_bearer = cb->args[0];
2838 	struct tipc_nl_msg msg;
2839 	int bearer_id;
2840 	int err;
2841 
2842 	if (prev_bearer == MAX_BEARERS)
2843 		return 0;
2844 
2845 	msg.skb = skb;
2846 	msg.portid = NETLINK_CB(cb->skb).portid;
2847 	msg.seq = cb->nlh->nlmsg_seq;
2848 
2849 	rtnl_lock();
2850 	for (bearer_id = prev_bearer; bearer_id < MAX_BEARERS; bearer_id++) {
2851 		err = __tipc_nl_add_monitor(net, &msg, bearer_id);
2852 		if (err)
2853 			break;
2854 	}
2855 	rtnl_unlock();
2856 	cb->args[0] = bearer_id;
2857 
2858 	return skb->len;
2859 }
2860 
2861 int tipc_nl_node_dump_monitor_peer(struct sk_buff *skb,
2862 				   struct netlink_callback *cb)
2863 {
2864 	struct net *net = sock_net(skb->sk);
2865 	u32 prev_node = cb->args[1];
2866 	u32 bearer_id = cb->args[2];
2867 	int done = cb->args[0];
2868 	struct tipc_nl_msg msg;
2869 	int err;
2870 
2871 	if (!prev_node) {
2872 		struct nlattr **attrs = genl_dumpit_info(cb)->info.attrs;
2873 		struct nlattr *mon[TIPC_NLA_MON_MAX + 1];
2874 
2875 		if (!attrs[TIPC_NLA_MON])
2876 			return -EINVAL;
2877 
2878 		err = nla_parse_nested_deprecated(mon, TIPC_NLA_MON_MAX,
2879 						  attrs[TIPC_NLA_MON],
2880 						  tipc_nl_monitor_policy,
2881 						  NULL);
2882 		if (err)
2883 			return err;
2884 
2885 		if (!mon[TIPC_NLA_MON_REF])
2886 			return -EINVAL;
2887 
2888 		bearer_id = nla_get_u32(mon[TIPC_NLA_MON_REF]);
2889 
2890 		if (bearer_id >= MAX_BEARERS)
2891 			return -EINVAL;
2892 	}
2893 
2894 	if (done)
2895 		return 0;
2896 
2897 	msg.skb = skb;
2898 	msg.portid = NETLINK_CB(cb->skb).portid;
2899 	msg.seq = cb->nlh->nlmsg_seq;
2900 
2901 	rtnl_lock();
2902 	err = tipc_nl_add_monitor_peer(net, &msg, bearer_id, &prev_node);
2903 	if (!err)
2904 		done = 1;
2905 
2906 	rtnl_unlock();
2907 	cb->args[0] = done;
2908 	cb->args[1] = prev_node;
2909 	cb->args[2] = bearer_id;
2910 
2911 	return skb->len;
2912 }
2913 
2914 #ifdef CONFIG_TIPC_CRYPTO
2915 static int tipc_nl_retrieve_key(struct nlattr **attrs,
2916 				struct tipc_aead_key **pkey)
2917 {
2918 	struct nlattr *attr = attrs[TIPC_NLA_NODE_KEY];
2919 	struct tipc_aead_key *key;
2920 
2921 	if (!attr)
2922 		return -ENODATA;
2923 
2924 	if (nla_len(attr) < sizeof(*key))
2925 		return -EINVAL;
2926 	key = (struct tipc_aead_key *)nla_data(attr);
2927 	if (key->keylen > TIPC_AEAD_KEYLEN_MAX ||
2928 	    nla_len(attr) < tipc_aead_key_size(key))
2929 		return -EINVAL;
2930 
2931 	*pkey = key;
2932 	return 0;
2933 }
2934 
2935 static int tipc_nl_retrieve_nodeid(struct nlattr **attrs, u8 **node_id)
2936 {
2937 	struct nlattr *attr = attrs[TIPC_NLA_NODE_ID];
2938 
2939 	if (!attr)
2940 		return -ENODATA;
2941 
2942 	if (nla_len(attr) < TIPC_NODEID_LEN)
2943 		return -EINVAL;
2944 
2945 	*node_id = (u8 *)nla_data(attr);
2946 	return 0;
2947 }
2948 
2949 static int tipc_nl_retrieve_rekeying(struct nlattr **attrs, u32 *intv)
2950 {
2951 	struct nlattr *attr = attrs[TIPC_NLA_NODE_REKEYING];
2952 
2953 	if (!attr)
2954 		return -ENODATA;
2955 
2956 	*intv = nla_get_u32(attr);
2957 	return 0;
2958 }
2959 
2960 static int __tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
2961 {
2962 	struct nlattr *attrs[TIPC_NLA_NODE_MAX + 1];
2963 	struct net *net = sock_net(skb->sk);
2964 	struct tipc_crypto *tx = tipc_net(net)->crypto_tx, *c = tx;
2965 	struct tipc_node *n = NULL;
2966 	struct tipc_aead_key *ukey;
2967 	bool rekeying = true, master_key = false;
2968 	u8 *id, *own_id, mode;
2969 	u32 intv = 0;
2970 	int rc = 0;
2971 
2972 	if (!info->attrs[TIPC_NLA_NODE])
2973 		return -EINVAL;
2974 
2975 	rc = nla_parse_nested(attrs, TIPC_NLA_NODE_MAX,
2976 			      info->attrs[TIPC_NLA_NODE],
2977 			      tipc_nl_node_policy, info->extack);
2978 	if (rc)
2979 		return rc;
2980 
2981 	own_id = tipc_own_id(net);
2982 	if (!own_id) {
2983 		GENL_SET_ERR_MSG(info, "not found own node identity (set id?)");
2984 		return -EPERM;
2985 	}
2986 
2987 	rc = tipc_nl_retrieve_rekeying(attrs, &intv);
2988 	if (rc == -ENODATA)
2989 		rekeying = false;
2990 
2991 	rc = tipc_nl_retrieve_key(attrs, &ukey);
2992 	if (rc == -ENODATA && rekeying)
2993 		goto rekeying;
2994 	else if (rc)
2995 		return rc;
2996 
2997 	rc = tipc_aead_key_validate(ukey, info);
2998 	if (rc)
2999 		return rc;
3000 
3001 	rc = tipc_nl_retrieve_nodeid(attrs, &id);
3002 	switch (rc) {
3003 	case -ENODATA:
3004 		mode = CLUSTER_KEY;
3005 		master_key = !!(attrs[TIPC_NLA_NODE_KEY_MASTER]);
3006 		break;
3007 	case 0:
3008 		mode = PER_NODE_KEY;
3009 		if (memcmp(id, own_id, NODE_ID_LEN)) {
3010 			n = tipc_node_find_by_id(net, id) ?:
3011 				tipc_node_create(net, 0, id, 0xffffu, 0, true);
3012 			if (unlikely(!n))
3013 				return -ENOMEM;
3014 			c = n->crypto_rx;
3015 		}
3016 		break;
3017 	default:
3018 		return rc;
3019 	}
3020 
3021 	/* Initiate the TX/RX key */
3022 	rc = tipc_crypto_key_init(c, ukey, mode, master_key);
3023 	if (n)
3024 		tipc_node_put(n);
3025 
3026 	if (unlikely(rc < 0)) {
3027 		GENL_SET_ERR_MSG(info, "unable to initiate or attach new key");
3028 		return rc;
3029 	} else if (c == tx) {
3030 		/* Distribute TX key but not master one */
3031 		if (!master_key && tipc_crypto_key_distr(tx, rc, NULL))
3032 			GENL_SET_ERR_MSG(info, "failed to replicate new key");
3033 rekeying:
3034 		/* Schedule TX rekeying if needed */
3035 		tipc_crypto_rekeying_sched(tx, rekeying, intv);
3036 	}
3037 
3038 	return 0;
3039 }
3040 
3041 int tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
3042 {
3043 	int err;
3044 
3045 	rtnl_lock();
3046 	err = __tipc_nl_node_set_key(skb, info);
3047 	rtnl_unlock();
3048 
3049 	return err;
3050 }
3051 
3052 static int __tipc_nl_node_flush_key(struct sk_buff *skb,
3053 				    struct genl_info *info)
3054 {
3055 	struct net *net = sock_net(skb->sk);
3056 	struct tipc_net *tn = tipc_net(net);
3057 	struct tipc_node *n;
3058 
3059 	tipc_crypto_key_flush(tn->crypto_tx);
3060 	rcu_read_lock();
3061 	list_for_each_entry_rcu(n, &tn->node_list, list)
3062 		tipc_crypto_key_flush(n->crypto_rx);
3063 	rcu_read_unlock();
3064 
3065 	return 0;
3066 }
3067 
3068 int tipc_nl_node_flush_key(struct sk_buff *skb, struct genl_info *info)
3069 {
3070 	int err;
3071 
3072 	rtnl_lock();
3073 	err = __tipc_nl_node_flush_key(skb, info);
3074 	rtnl_unlock();
3075 
3076 	return err;
3077 }
3078 #endif
3079 
3080 /**
3081  * tipc_node_dump - dump TIPC node data
3082  * @n: tipc node to be dumped
3083  * @more: dump more?
3084  *        - false: dump only tipc node data
3085  *        - true: dump node link data as well
3086  * @buf: returned buffer of dump data in format
3087  */
3088 int tipc_node_dump(struct tipc_node *n, bool more, char *buf)
3089 {
3090 	int i = 0;
3091 	size_t sz = (more) ? NODE_LMAX : NODE_LMIN;
3092 
3093 	if (!n) {
3094 		i += scnprintf(buf, sz, "node data: (null)\n");
3095 		return i;
3096 	}
3097 
3098 	i += scnprintf(buf, sz, "node data: %x", n->addr);
3099 	i += scnprintf(buf + i, sz - i, " %x", n->state);
3100 	i += scnprintf(buf + i, sz - i, " %d", n->active_links[0]);
3101 	i += scnprintf(buf + i, sz - i, " %d", n->active_links[1]);
3102 	i += scnprintf(buf + i, sz - i, " %x", n->action_flags);
3103 	i += scnprintf(buf + i, sz - i, " %u", n->failover_sent);
3104 	i += scnprintf(buf + i, sz - i, " %u", n->sync_point);
3105 	i += scnprintf(buf + i, sz - i, " %d", n->link_cnt);
3106 	i += scnprintf(buf + i, sz - i, " %u", n->working_links);
3107 	i += scnprintf(buf + i, sz - i, " %x", n->capabilities);
3108 	i += scnprintf(buf + i, sz - i, " %lu\n", n->keepalive_intv);
3109 
3110 	if (!more)
3111 		return i;
3112 
3113 	i += scnprintf(buf + i, sz - i, "link_entry[0]:\n");
3114 	i += scnprintf(buf + i, sz - i, " mtu: %u\n", n->links[0].mtu);
3115 	i += scnprintf(buf + i, sz - i, " media: ");
3116 	i += tipc_media_addr_printf(buf + i, sz - i, &n->links[0].maddr);
3117 	i += scnprintf(buf + i, sz - i, "\n");
3118 	i += tipc_link_dump(n->links[0].link, TIPC_DUMP_NONE, buf + i);
3119 	i += scnprintf(buf + i, sz - i, " inputq: ");
3120 	i += tipc_list_dump(&n->links[0].inputq, false, buf + i);
3121 
3122 	i += scnprintf(buf + i, sz - i, "link_entry[1]:\n");
3123 	i += scnprintf(buf + i, sz - i, " mtu: %u\n", n->links[1].mtu);
3124 	i += scnprintf(buf + i, sz - i, " media: ");
3125 	i += tipc_media_addr_printf(buf + i, sz - i, &n->links[1].maddr);
3126 	i += scnprintf(buf + i, sz - i, "\n");
3127 	i += tipc_link_dump(n->links[1].link, TIPC_DUMP_NONE, buf + i);
3128 	i += scnprintf(buf + i, sz - i, " inputq: ");
3129 	i += tipc_list_dump(&n->links[1].inputq, false, buf + i);
3130 
3131 	i += scnprintf(buf + i, sz - i, "bclink:\n ");
3132 	i += tipc_link_dump(n->bc_entry.link, TIPC_DUMP_NONE, buf + i);
3133 
3134 	return i;
3135 }
3136 
3137 void tipc_node_pre_cleanup_net(struct net *exit_net)
3138 {
3139 	struct tipc_node *n;
3140 	struct tipc_net *tn;
3141 	struct net *tmp;
3142 
3143 	rcu_read_lock();
3144 	for_each_net_rcu(tmp) {
3145 		if (tmp == exit_net)
3146 			continue;
3147 		tn = tipc_net(tmp);
3148 		if (!tn)
3149 			continue;
3150 		spin_lock_bh(&tn->node_list_lock);
3151 		list_for_each_entry_rcu(n, &tn->node_list, list) {
3152 			if (!n->peer_net)
3153 				continue;
3154 			if (n->peer_net != exit_net)
3155 				continue;
3156 			tipc_node_write_lock(n);
3157 			n->peer_net = NULL;
3158 			n->peer_hash_mix = 0;
3159 			tipc_node_write_unlock_fast(n);
3160 			break;
3161 		}
3162 		spin_unlock_bh(&tn->node_list_lock);
3163 	}
3164 	rcu_read_unlock();
3165 }
3166