xref: /linux/net/tipc/node.c (revision 950b6662e26e381cf8834b9b78b08261890ee697)
1 /*
2  * net/tipc/node.c: TIPC node management routines
3  *
4  * Copyright (c) 2000-2006, 2012-2016, Ericsson AB
5  * Copyright (c) 2005-2006, 2010-2014, Wind River Systems
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the names of the copyright holders nor the names of its
17  *    contributors may be used to endorse or promote products derived from
18  *    this software without specific prior written permission.
19  *
20  * Alternatively, this software may be distributed under the terms of the
21  * GNU General Public License ("GPL") version 2 as published by the Free
22  * Software Foundation.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34  * POSSIBILITY OF SUCH DAMAGE.
35  */
36 
37 #include "core.h"
38 #include "link.h"
39 #include "node.h"
40 #include "name_distr.h"
41 #include "socket.h"
42 #include "bcast.h"
43 #include "monitor.h"
44 #include "discover.h"
45 #include "netlink.h"
46 #include "trace.h"
47 #include "crypto.h"
48 
49 #define INVALID_NODE_SIG	0x10000
50 #define NODE_CLEANUP_AFTER	300000
51 
52 /* Flags used to take different actions according to flag type
53  * TIPC_NOTIFY_NODE_DOWN: notify node is down
54  * TIPC_NOTIFY_NODE_UP: notify node is up
55  * TIPC_DISTRIBUTE_NAME: publish or withdraw link state name type
56  */
57 enum {
58 	TIPC_NOTIFY_NODE_DOWN		= (1 << 3),
59 	TIPC_NOTIFY_NODE_UP		= (1 << 4),
60 	TIPC_NOTIFY_LINK_UP		= (1 << 6),
61 	TIPC_NOTIFY_LINK_DOWN		= (1 << 7)
62 };
63 
64 struct tipc_link_entry {
65 	struct tipc_link *link;
66 	spinlock_t lock; /* per link */
67 	u32 mtu;
68 	struct sk_buff_head inputq;
69 	struct tipc_media_addr maddr;
70 };
71 
72 struct tipc_bclink_entry {
73 	struct tipc_link *link;
74 	struct sk_buff_head inputq1;
75 	struct sk_buff_head arrvq;
76 	struct sk_buff_head inputq2;
77 	struct sk_buff_head namedq;
78 	u16 named_rcv_nxt;
79 	bool named_open;
80 };
81 
82 /**
83  * struct tipc_node - TIPC node structure
84  * @addr: network address of node
85  * @kref: reference counter to node object
86  * @lock: rwlock governing access to structure
87  * @net: the applicable net namespace
88  * @hash: links to adjacent nodes in unsorted hash chain
89  * @inputq: pointer to input queue containing messages for msg event
90  * @namedq: pointer to name table input queue with name table messages
91  * @active_links: bearer ids of active links, used as index into links[] array
92  * @links: array containing references to all links to node
93  * @bc_entry: broadcast link entry
94  * @action_flags: bit mask of different types of node actions
95  * @state: connectivity state vs peer node
96  * @preliminary: a preliminary node or not
97  * @failover_sent: failover sent or not
98  * @sync_point: sequence number where synch/failover is finished
99  * @list: links to adjacent nodes in sorted list of cluster's nodes
100  * @working_links: number of working links to node (both active and standby)
101  * @link_cnt: number of links to node
102  * @capabilities: bitmap, indicating peer node's functional capabilities
103  * @signature: node instance identifier
104  * @link_id: local and remote bearer ids of changing link, if any
105  * @peer_id: 128-bit ID of peer
106  * @peer_id_string: ID string of peer
107  * @publ_list: list of publications
108  * @conn_sks: list of connections (FIXME)
109  * @timer: node's keepalive timer
110  * @keepalive_intv: keepalive interval in milliseconds
111  * @rcu: rcu struct for tipc_node
112  * @delete_at: indicates the time for deleting a down node
113  * @peer_net: peer's net namespace
114  * @peer_hash_mix: hash for this peer (FIXME)
115  * @crypto_rx: RX crypto handler
116  */
117 struct tipc_node {
118 	u32 addr;
119 	struct kref kref;
120 	rwlock_t lock;
121 	struct net *net;
122 	struct hlist_node hash;
123 	int active_links[2];
124 	struct tipc_link_entry links[MAX_BEARERS];
125 	struct tipc_bclink_entry bc_entry;
126 	int action_flags;
127 	struct list_head list;
128 	int state;
129 	bool preliminary;
130 	bool failover_sent;
131 	u16 sync_point;
132 	int link_cnt;
133 	u16 working_links;
134 	u16 capabilities;
135 	u32 signature;
136 	u32 link_id;
137 	u8 peer_id[16];
138 	char peer_id_string[NODE_ID_STR_LEN];
139 	struct list_head publ_list;
140 	struct list_head conn_sks;
141 	unsigned long keepalive_intv;
142 	struct timer_list timer;
143 	struct rcu_head rcu;
144 	unsigned long delete_at;
145 	struct net *peer_net;
146 	u32 peer_hash_mix;
147 #ifdef CONFIG_TIPC_CRYPTO
148 	struct tipc_crypto *crypto_rx;
149 #endif
150 };
151 
152 /* Node FSM states and events:
153  */
154 enum {
155 	SELF_DOWN_PEER_DOWN    = 0xdd,
156 	SELF_UP_PEER_UP        = 0xaa,
157 	SELF_DOWN_PEER_LEAVING = 0xd1,
158 	SELF_UP_PEER_COMING    = 0xac,
159 	SELF_COMING_PEER_UP    = 0xca,
160 	SELF_LEAVING_PEER_DOWN = 0x1d,
161 	NODE_FAILINGOVER       = 0xf0,
162 	NODE_SYNCHING          = 0xcc
163 };
164 
165 enum {
166 	SELF_ESTABL_CONTACT_EVT = 0xece,
167 	SELF_LOST_CONTACT_EVT   = 0x1ce,
168 	PEER_ESTABL_CONTACT_EVT = 0x9ece,
169 	PEER_LOST_CONTACT_EVT   = 0x91ce,
170 	NODE_FAILOVER_BEGIN_EVT = 0xfbe,
171 	NODE_FAILOVER_END_EVT   = 0xfee,
172 	NODE_SYNCH_BEGIN_EVT    = 0xcbe,
173 	NODE_SYNCH_END_EVT      = 0xcee
174 };
175 
176 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
177 				  struct sk_buff_head *xmitq,
178 				  struct tipc_media_addr **maddr);
179 static void tipc_node_link_down(struct tipc_node *n, int bearer_id,
180 				bool delete);
181 static void node_lost_contact(struct tipc_node *n, struct sk_buff_head *inputq);
182 static void tipc_node_delete(struct tipc_node *node);
183 static void tipc_node_timeout(struct timer_list *t);
184 static void tipc_node_fsm_evt(struct tipc_node *n, int evt);
185 static struct tipc_node *tipc_node_find(struct net *net, u32 addr);
186 static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id);
187 static bool node_is_up(struct tipc_node *n);
188 static void tipc_node_delete_from_list(struct tipc_node *node);
189 
190 struct tipc_sock_conn {
191 	u32 port;
192 	u32 peer_port;
193 	u32 peer_node;
194 	struct list_head list;
195 };
196 
197 static struct tipc_link *node_active_link(struct tipc_node *n, int sel)
198 {
199 	int bearer_id = n->active_links[sel & 1];
200 
201 	if (unlikely(bearer_id == INVALID_BEARER_ID))
202 		return NULL;
203 
204 	return n->links[bearer_id].link;
205 }
206 
207 int tipc_node_get_mtu(struct net *net, u32 addr, u32 sel, bool connected)
208 {
209 	struct tipc_node *n;
210 	int bearer_id;
211 	unsigned int mtu = MAX_MSG_SIZE;
212 
213 	n = tipc_node_find(net, addr);
214 	if (unlikely(!n))
215 		return mtu;
216 
217 	/* Allow MAX_MSG_SIZE when building connection oriented message
218 	 * if they are in the same core network
219 	 */
220 	if (n->peer_net && connected) {
221 		tipc_node_put(n);
222 		return mtu;
223 	}
224 
225 	bearer_id = n->active_links[sel & 1];
226 	if (likely(bearer_id != INVALID_BEARER_ID))
227 		mtu = n->links[bearer_id].mtu;
228 	tipc_node_put(n);
229 	return mtu;
230 }
231 
232 bool tipc_node_get_id(struct net *net, u32 addr, u8 *id)
233 {
234 	u8 *own_id = tipc_own_id(net);
235 	struct tipc_node *n;
236 
237 	if (!own_id)
238 		return true;
239 
240 	if (addr == tipc_own_addr(net)) {
241 		memcpy(id, own_id, TIPC_NODEID_LEN);
242 		return true;
243 	}
244 	n = tipc_node_find(net, addr);
245 	if (!n)
246 		return false;
247 
248 	memcpy(id, &n->peer_id, TIPC_NODEID_LEN);
249 	tipc_node_put(n);
250 	return true;
251 }
252 
253 u16 tipc_node_get_capabilities(struct net *net, u32 addr)
254 {
255 	struct tipc_node *n;
256 	u16 caps;
257 
258 	n = tipc_node_find(net, addr);
259 	if (unlikely(!n))
260 		return TIPC_NODE_CAPABILITIES;
261 	caps = n->capabilities;
262 	tipc_node_put(n);
263 	return caps;
264 }
265 
266 u32 tipc_node_get_addr(struct tipc_node *node)
267 {
268 	return (node) ? node->addr : 0;
269 }
270 
271 char *tipc_node_get_id_str(struct tipc_node *node)
272 {
273 	return node->peer_id_string;
274 }
275 
276 #ifdef CONFIG_TIPC_CRYPTO
277 /**
278  * tipc_node_crypto_rx - Retrieve crypto RX handle from node
279  * @__n: target tipc_node
280  * Note: node ref counter must be held first!
281  */
282 struct tipc_crypto *tipc_node_crypto_rx(struct tipc_node *__n)
283 {
284 	return (__n) ? __n->crypto_rx : NULL;
285 }
286 
287 struct tipc_crypto *tipc_node_crypto_rx_by_list(struct list_head *pos)
288 {
289 	return container_of(pos, struct tipc_node, list)->crypto_rx;
290 }
291 
292 struct tipc_crypto *tipc_node_crypto_rx_by_addr(struct net *net, u32 addr)
293 {
294 	struct tipc_node *n;
295 
296 	n = tipc_node_find(net, addr);
297 	return (n) ? n->crypto_rx : NULL;
298 }
299 #endif
300 
301 static void tipc_node_free(struct rcu_head *rp)
302 {
303 	struct tipc_node *n = container_of(rp, struct tipc_node, rcu);
304 
305 #ifdef CONFIG_TIPC_CRYPTO
306 	tipc_crypto_stop(&n->crypto_rx);
307 #endif
308 	kfree(n);
309 }
310 
311 static void tipc_node_kref_release(struct kref *kref)
312 {
313 	struct tipc_node *n = container_of(kref, struct tipc_node, kref);
314 
315 	kfree(n->bc_entry.link);
316 	call_rcu(&n->rcu, tipc_node_free);
317 }
318 
319 void tipc_node_put(struct tipc_node *node)
320 {
321 	kref_put(&node->kref, tipc_node_kref_release);
322 }
323 
324 void tipc_node_get(struct tipc_node *node)
325 {
326 	kref_get(&node->kref);
327 }
328 
329 /*
330  * tipc_node_find - locate specified node object, if it exists
331  */
332 static struct tipc_node *tipc_node_find(struct net *net, u32 addr)
333 {
334 	struct tipc_net *tn = tipc_net(net);
335 	struct tipc_node *node;
336 	unsigned int thash = tipc_hashfn(addr);
337 
338 	rcu_read_lock();
339 	hlist_for_each_entry_rcu(node, &tn->node_htable[thash], hash) {
340 		if (node->addr != addr || node->preliminary)
341 			continue;
342 		if (!kref_get_unless_zero(&node->kref))
343 			node = NULL;
344 		break;
345 	}
346 	rcu_read_unlock();
347 	return node;
348 }
349 
350 /* tipc_node_find_by_id - locate specified node object by its 128-bit id
351  * Note: this function is called only when a discovery request failed
352  * to find the node by its 32-bit id, and is not time critical
353  */
354 static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id)
355 {
356 	struct tipc_net *tn = tipc_net(net);
357 	struct tipc_node *n;
358 	bool found = false;
359 
360 	rcu_read_lock();
361 	list_for_each_entry_rcu(n, &tn->node_list, list) {
362 		read_lock_bh(&n->lock);
363 		if (!memcmp(id, n->peer_id, 16) &&
364 		    kref_get_unless_zero(&n->kref))
365 			found = true;
366 		read_unlock_bh(&n->lock);
367 		if (found)
368 			break;
369 	}
370 	rcu_read_unlock();
371 	return found ? n : NULL;
372 }
373 
374 static void tipc_node_read_lock(struct tipc_node *n)
375 	__acquires(n->lock)
376 {
377 	read_lock_bh(&n->lock);
378 }
379 
380 static void tipc_node_read_unlock(struct tipc_node *n)
381 	__releases(n->lock)
382 {
383 	read_unlock_bh(&n->lock);
384 }
385 
386 static void tipc_node_write_lock(struct tipc_node *n)
387 	__acquires(n->lock)
388 {
389 	write_lock_bh(&n->lock);
390 }
391 
392 static void tipc_node_write_unlock_fast(struct tipc_node *n)
393 	__releases(n->lock)
394 {
395 	write_unlock_bh(&n->lock);
396 }
397 
398 static void tipc_node_write_unlock(struct tipc_node *n)
399 	__releases(n->lock)
400 {
401 	struct tipc_socket_addr sk;
402 	struct net *net = n->net;
403 	u32 flags = n->action_flags;
404 	struct list_head *publ_list;
405 	struct tipc_uaddr ua;
406 	u32 bearer_id, node;
407 
408 	if (likely(!flags)) {
409 		write_unlock_bh(&n->lock);
410 		return;
411 	}
412 
413 	tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_NODE_SCOPE,
414 		   TIPC_LINK_STATE, n->addr, n->addr);
415 	sk.ref = n->link_id;
416 	sk.node = tipc_own_addr(net);
417 	node = n->addr;
418 	bearer_id = n->link_id & 0xffff;
419 	publ_list = &n->publ_list;
420 
421 	n->action_flags &= ~(TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP |
422 			     TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP);
423 
424 	write_unlock_bh(&n->lock);
425 
426 	if (flags & TIPC_NOTIFY_NODE_DOWN)
427 		tipc_publ_notify(net, publ_list, node, n->capabilities);
428 
429 	if (flags & TIPC_NOTIFY_NODE_UP)
430 		tipc_named_node_up(net, node, n->capabilities);
431 
432 	if (flags & TIPC_NOTIFY_LINK_UP) {
433 		tipc_mon_peer_up(net, node, bearer_id);
434 		tipc_nametbl_publish(net, &ua, &sk, sk.ref);
435 	}
436 	if (flags & TIPC_NOTIFY_LINK_DOWN) {
437 		tipc_mon_peer_down(net, node, bearer_id);
438 		tipc_nametbl_withdraw(net, &ua, &sk, sk.ref);
439 	}
440 }
441 
442 static void tipc_node_assign_peer_net(struct tipc_node *n, u32 hash_mixes)
443 {
444 	int net_id = tipc_netid(n->net);
445 	struct tipc_net *tn_peer;
446 	struct net *tmp;
447 	u32 hash_chk;
448 
449 	if (n->peer_net)
450 		return;
451 
452 	for_each_net_rcu(tmp) {
453 		tn_peer = tipc_net(tmp);
454 		if (!tn_peer)
455 			continue;
456 		/* Integrity checking whether node exists in namespace or not */
457 		if (tn_peer->net_id != net_id)
458 			continue;
459 		if (memcmp(n->peer_id, tn_peer->node_id, NODE_ID_LEN))
460 			continue;
461 		hash_chk = tipc_net_hash_mixes(tmp, tn_peer->random);
462 		if (hash_mixes ^ hash_chk)
463 			continue;
464 		n->peer_net = tmp;
465 		n->peer_hash_mix = hash_mixes;
466 		break;
467 	}
468 }
469 
470 struct tipc_node *tipc_node_create(struct net *net, u32 addr, u8 *peer_id,
471 				   u16 capabilities, u32 hash_mixes,
472 				   bool preliminary)
473 {
474 	struct tipc_net *tn = net_generic(net, tipc_net_id);
475 	struct tipc_link *l, *snd_l = tipc_bc_sndlink(net);
476 	struct tipc_node *n, *temp_node;
477 	unsigned long intv;
478 	int bearer_id;
479 	int i;
480 
481 	spin_lock_bh(&tn->node_list_lock);
482 	n = tipc_node_find(net, addr) ?:
483 		tipc_node_find_by_id(net, peer_id);
484 	if (n) {
485 		if (!n->preliminary)
486 			goto update;
487 		if (preliminary)
488 			goto exit;
489 		/* A preliminary node becomes "real" now, refresh its data */
490 		tipc_node_write_lock(n);
491 		if (!tipc_link_bc_create(net, tipc_own_addr(net), addr, peer_id, U16_MAX,
492 					 tipc_link_min_win(snd_l), tipc_link_max_win(snd_l),
493 					 n->capabilities, &n->bc_entry.inputq1,
494 					 &n->bc_entry.namedq, snd_l, &n->bc_entry.link)) {
495 			pr_warn("Broadcast rcv link refresh failed, no memory\n");
496 			tipc_node_write_unlock_fast(n);
497 			tipc_node_put(n);
498 			n = NULL;
499 			goto exit;
500 		}
501 		n->preliminary = false;
502 		n->addr = addr;
503 		hlist_del_rcu(&n->hash);
504 		hlist_add_head_rcu(&n->hash,
505 				   &tn->node_htable[tipc_hashfn(addr)]);
506 		list_del_rcu(&n->list);
507 		list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
508 			if (n->addr < temp_node->addr)
509 				break;
510 		}
511 		list_add_tail_rcu(&n->list, &temp_node->list);
512 		tipc_node_write_unlock_fast(n);
513 
514 update:
515 		if (n->peer_hash_mix ^ hash_mixes)
516 			tipc_node_assign_peer_net(n, hash_mixes);
517 		if (n->capabilities == capabilities)
518 			goto exit;
519 		/* Same node may come back with new capabilities */
520 		tipc_node_write_lock(n);
521 		n->capabilities = capabilities;
522 		for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
523 			l = n->links[bearer_id].link;
524 			if (l)
525 				tipc_link_update_caps(l, capabilities);
526 		}
527 		tipc_node_write_unlock_fast(n);
528 
529 		/* Calculate cluster capabilities */
530 		tn->capabilities = TIPC_NODE_CAPABILITIES;
531 		list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
532 			tn->capabilities &= temp_node->capabilities;
533 		}
534 
535 		tipc_bcast_toggle_rcast(net,
536 					(tn->capabilities & TIPC_BCAST_RCAST));
537 
538 		goto exit;
539 	}
540 	n = kzalloc(sizeof(*n), GFP_ATOMIC);
541 	if (!n) {
542 		pr_warn("Node creation failed, no memory\n");
543 		goto exit;
544 	}
545 	tipc_nodeid2string(n->peer_id_string, peer_id);
546 #ifdef CONFIG_TIPC_CRYPTO
547 	if (unlikely(tipc_crypto_start(&n->crypto_rx, net, n))) {
548 		pr_warn("Failed to start crypto RX(%s)!\n", n->peer_id_string);
549 		kfree(n);
550 		n = NULL;
551 		goto exit;
552 	}
553 #endif
554 	n->addr = addr;
555 	n->preliminary = preliminary;
556 	memcpy(&n->peer_id, peer_id, 16);
557 	n->net = net;
558 	n->peer_net = NULL;
559 	n->peer_hash_mix = 0;
560 	/* Assign kernel local namespace if exists */
561 	tipc_node_assign_peer_net(n, hash_mixes);
562 	n->capabilities = capabilities;
563 	kref_init(&n->kref);
564 	rwlock_init(&n->lock);
565 	INIT_HLIST_NODE(&n->hash);
566 	INIT_LIST_HEAD(&n->list);
567 	INIT_LIST_HEAD(&n->publ_list);
568 	INIT_LIST_HEAD(&n->conn_sks);
569 	skb_queue_head_init(&n->bc_entry.namedq);
570 	skb_queue_head_init(&n->bc_entry.inputq1);
571 	__skb_queue_head_init(&n->bc_entry.arrvq);
572 	skb_queue_head_init(&n->bc_entry.inputq2);
573 	for (i = 0; i < MAX_BEARERS; i++)
574 		spin_lock_init(&n->links[i].lock);
575 	n->state = SELF_DOWN_PEER_LEAVING;
576 	n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
577 	n->signature = INVALID_NODE_SIG;
578 	n->active_links[0] = INVALID_BEARER_ID;
579 	n->active_links[1] = INVALID_BEARER_ID;
580 	if (!preliminary &&
581 	    !tipc_link_bc_create(net, tipc_own_addr(net), addr, peer_id, U16_MAX,
582 				 tipc_link_min_win(snd_l), tipc_link_max_win(snd_l),
583 				 n->capabilities, &n->bc_entry.inputq1,
584 				 &n->bc_entry.namedq, snd_l, &n->bc_entry.link)) {
585 		pr_warn("Broadcast rcv link creation failed, no memory\n");
586 		kfree(n);
587 		n = NULL;
588 		goto exit;
589 	}
590 	tipc_node_get(n);
591 	timer_setup(&n->timer, tipc_node_timeout, 0);
592 	/* Start a slow timer anyway, crypto needs it */
593 	n->keepalive_intv = 10000;
594 	intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
595 	if (!mod_timer(&n->timer, intv))
596 		tipc_node_get(n);
597 	hlist_add_head_rcu(&n->hash, &tn->node_htable[tipc_hashfn(addr)]);
598 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
599 		if (n->addr < temp_node->addr)
600 			break;
601 	}
602 	list_add_tail_rcu(&n->list, &temp_node->list);
603 	/* Calculate cluster capabilities */
604 	tn->capabilities = TIPC_NODE_CAPABILITIES;
605 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
606 		tn->capabilities &= temp_node->capabilities;
607 	}
608 	tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
609 	trace_tipc_node_create(n, true, " ");
610 exit:
611 	spin_unlock_bh(&tn->node_list_lock);
612 	return n;
613 }
614 
615 static void tipc_node_calculate_timer(struct tipc_node *n, struct tipc_link *l)
616 {
617 	unsigned long tol = tipc_link_tolerance(l);
618 	unsigned long intv = ((tol / 4) > 500) ? 500 : tol / 4;
619 
620 	/* Link with lowest tolerance determines timer interval */
621 	if (intv < n->keepalive_intv)
622 		n->keepalive_intv = intv;
623 
624 	/* Ensure link's abort limit corresponds to current tolerance */
625 	tipc_link_set_abort_limit(l, tol / n->keepalive_intv);
626 }
627 
628 static void tipc_node_delete_from_list(struct tipc_node *node)
629 {
630 #ifdef CONFIG_TIPC_CRYPTO
631 	tipc_crypto_key_flush(node->crypto_rx);
632 #endif
633 	list_del_rcu(&node->list);
634 	hlist_del_rcu(&node->hash);
635 	tipc_node_put(node);
636 }
637 
638 static void tipc_node_delete(struct tipc_node *node)
639 {
640 	trace_tipc_node_delete(node, true, " ");
641 	tipc_node_delete_from_list(node);
642 
643 	del_timer_sync(&node->timer);
644 	tipc_node_put(node);
645 }
646 
647 void tipc_node_stop(struct net *net)
648 {
649 	struct tipc_net *tn = tipc_net(net);
650 	struct tipc_node *node, *t_node;
651 
652 	spin_lock_bh(&tn->node_list_lock);
653 	list_for_each_entry_safe(node, t_node, &tn->node_list, list)
654 		tipc_node_delete(node);
655 	spin_unlock_bh(&tn->node_list_lock);
656 }
657 
658 void tipc_node_subscribe(struct net *net, struct list_head *subscr, u32 addr)
659 {
660 	struct tipc_node *n;
661 
662 	if (in_own_node(net, addr))
663 		return;
664 
665 	n = tipc_node_find(net, addr);
666 	if (!n) {
667 		pr_warn("Node subscribe rejected, unknown node 0x%x\n", addr);
668 		return;
669 	}
670 	tipc_node_write_lock(n);
671 	list_add_tail(subscr, &n->publ_list);
672 	tipc_node_write_unlock_fast(n);
673 	tipc_node_put(n);
674 }
675 
676 void tipc_node_unsubscribe(struct net *net, struct list_head *subscr, u32 addr)
677 {
678 	struct tipc_node *n;
679 
680 	if (in_own_node(net, addr))
681 		return;
682 
683 	n = tipc_node_find(net, addr);
684 	if (!n) {
685 		pr_warn("Node unsubscribe rejected, unknown node 0x%x\n", addr);
686 		return;
687 	}
688 	tipc_node_write_lock(n);
689 	list_del_init(subscr);
690 	tipc_node_write_unlock_fast(n);
691 	tipc_node_put(n);
692 }
693 
694 int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port)
695 {
696 	struct tipc_node *node;
697 	struct tipc_sock_conn *conn;
698 	int err = 0;
699 
700 	if (in_own_node(net, dnode))
701 		return 0;
702 
703 	node = tipc_node_find(net, dnode);
704 	if (!node) {
705 		pr_warn("Connecting sock to node 0x%x failed\n", dnode);
706 		return -EHOSTUNREACH;
707 	}
708 	conn = kmalloc(sizeof(*conn), GFP_ATOMIC);
709 	if (!conn) {
710 		err = -EHOSTUNREACH;
711 		goto exit;
712 	}
713 	conn->peer_node = dnode;
714 	conn->port = port;
715 	conn->peer_port = peer_port;
716 
717 	tipc_node_write_lock(node);
718 	list_add_tail(&conn->list, &node->conn_sks);
719 	tipc_node_write_unlock(node);
720 exit:
721 	tipc_node_put(node);
722 	return err;
723 }
724 
725 void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port)
726 {
727 	struct tipc_node *node;
728 	struct tipc_sock_conn *conn, *safe;
729 
730 	if (in_own_node(net, dnode))
731 		return;
732 
733 	node = tipc_node_find(net, dnode);
734 	if (!node)
735 		return;
736 
737 	tipc_node_write_lock(node);
738 	list_for_each_entry_safe(conn, safe, &node->conn_sks, list) {
739 		if (port != conn->port)
740 			continue;
741 		list_del(&conn->list);
742 		kfree(conn);
743 	}
744 	tipc_node_write_unlock(node);
745 	tipc_node_put(node);
746 }
747 
748 static void  tipc_node_clear_links(struct tipc_node *node)
749 {
750 	int i;
751 
752 	for (i = 0; i < MAX_BEARERS; i++) {
753 		struct tipc_link_entry *le = &node->links[i];
754 
755 		if (le->link) {
756 			kfree(le->link);
757 			le->link = NULL;
758 			node->link_cnt--;
759 		}
760 	}
761 }
762 
763 /* tipc_node_cleanup - delete nodes that does not
764  * have active links for NODE_CLEANUP_AFTER time
765  */
766 static bool tipc_node_cleanup(struct tipc_node *peer)
767 {
768 	struct tipc_node *temp_node;
769 	struct tipc_net *tn = tipc_net(peer->net);
770 	bool deleted = false;
771 
772 	/* If lock held by tipc_node_stop() the node will be deleted anyway */
773 	if (!spin_trylock_bh(&tn->node_list_lock))
774 		return false;
775 
776 	tipc_node_write_lock(peer);
777 
778 	if (!node_is_up(peer) && time_after(jiffies, peer->delete_at)) {
779 		tipc_node_clear_links(peer);
780 		tipc_node_delete_from_list(peer);
781 		deleted = true;
782 	}
783 	tipc_node_write_unlock(peer);
784 
785 	if (!deleted) {
786 		spin_unlock_bh(&tn->node_list_lock);
787 		return deleted;
788 	}
789 
790 	/* Calculate cluster capabilities */
791 	tn->capabilities = TIPC_NODE_CAPABILITIES;
792 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
793 		tn->capabilities &= temp_node->capabilities;
794 	}
795 	tipc_bcast_toggle_rcast(peer->net,
796 				(tn->capabilities & TIPC_BCAST_RCAST));
797 	spin_unlock_bh(&tn->node_list_lock);
798 	return deleted;
799 }
800 
801 /* tipc_node_timeout - handle expiration of node timer
802  */
803 static void tipc_node_timeout(struct timer_list *t)
804 {
805 	struct tipc_node *n = from_timer(n, t, timer);
806 	struct tipc_link_entry *le;
807 	struct sk_buff_head xmitq;
808 	int remains = n->link_cnt;
809 	int bearer_id;
810 	int rc = 0;
811 
812 	trace_tipc_node_timeout(n, false, " ");
813 	if (!node_is_up(n) && tipc_node_cleanup(n)) {
814 		/*Removing the reference of Timer*/
815 		tipc_node_put(n);
816 		return;
817 	}
818 
819 #ifdef CONFIG_TIPC_CRYPTO
820 	/* Take any crypto key related actions first */
821 	tipc_crypto_timeout(n->crypto_rx);
822 #endif
823 	__skb_queue_head_init(&xmitq);
824 
825 	/* Initial node interval to value larger (10 seconds), then it will be
826 	 * recalculated with link lowest tolerance
827 	 */
828 	tipc_node_read_lock(n);
829 	n->keepalive_intv = 10000;
830 	tipc_node_read_unlock(n);
831 	for (bearer_id = 0; remains && (bearer_id < MAX_BEARERS); bearer_id++) {
832 		tipc_node_read_lock(n);
833 		le = &n->links[bearer_id];
834 		if (le->link) {
835 			spin_lock_bh(&le->lock);
836 			/* Link tolerance may change asynchronously: */
837 			tipc_node_calculate_timer(n, le->link);
838 			rc = tipc_link_timeout(le->link, &xmitq);
839 			spin_unlock_bh(&le->lock);
840 			remains--;
841 		}
842 		tipc_node_read_unlock(n);
843 		tipc_bearer_xmit(n->net, bearer_id, &xmitq, &le->maddr, n);
844 		if (rc & TIPC_LINK_DOWN_EVT)
845 			tipc_node_link_down(n, bearer_id, false);
846 	}
847 	mod_timer(&n->timer, jiffies + msecs_to_jiffies(n->keepalive_intv));
848 }
849 
850 /**
851  * __tipc_node_link_up - handle addition of link
852  * @n: target tipc_node
853  * @bearer_id: id of the bearer
854  * @xmitq: queue for messages to be xmited on
855  * Node lock must be held by caller
856  * Link becomes active (alone or shared) or standby, depending on its priority.
857  */
858 static void __tipc_node_link_up(struct tipc_node *n, int bearer_id,
859 				struct sk_buff_head *xmitq)
860 {
861 	int *slot0 = &n->active_links[0];
862 	int *slot1 = &n->active_links[1];
863 	struct tipc_link *ol = node_active_link(n, 0);
864 	struct tipc_link *nl = n->links[bearer_id].link;
865 
866 	if (!nl || tipc_link_is_up(nl))
867 		return;
868 
869 	tipc_link_fsm_evt(nl, LINK_ESTABLISH_EVT);
870 	if (!tipc_link_is_up(nl))
871 		return;
872 
873 	n->working_links++;
874 	n->action_flags |= TIPC_NOTIFY_LINK_UP;
875 	n->link_id = tipc_link_id(nl);
876 
877 	/* Leave room for tunnel header when returning 'mtu' to users: */
878 	n->links[bearer_id].mtu = tipc_link_mss(nl);
879 
880 	tipc_bearer_add_dest(n->net, bearer_id, n->addr);
881 	tipc_bcast_inc_bearer_dst_cnt(n->net, bearer_id);
882 
883 	pr_debug("Established link <%s> on network plane %c\n",
884 		 tipc_link_name(nl), tipc_link_plane(nl));
885 	trace_tipc_node_link_up(n, true, " ");
886 
887 	/* Ensure that a STATE message goes first */
888 	tipc_link_build_state_msg(nl, xmitq);
889 
890 	/* First link? => give it both slots */
891 	if (!ol) {
892 		*slot0 = bearer_id;
893 		*slot1 = bearer_id;
894 		tipc_node_fsm_evt(n, SELF_ESTABL_CONTACT_EVT);
895 		n->action_flags |= TIPC_NOTIFY_NODE_UP;
896 		tipc_link_set_active(nl, true);
897 		tipc_bcast_add_peer(n->net, nl, xmitq);
898 		return;
899 	}
900 
901 	/* Second link => redistribute slots */
902 	if (tipc_link_prio(nl) > tipc_link_prio(ol)) {
903 		pr_debug("Old link <%s> becomes standby\n", tipc_link_name(ol));
904 		*slot0 = bearer_id;
905 		*slot1 = bearer_id;
906 		tipc_link_set_active(nl, true);
907 		tipc_link_set_active(ol, false);
908 	} else if (tipc_link_prio(nl) == tipc_link_prio(ol)) {
909 		tipc_link_set_active(nl, true);
910 		*slot1 = bearer_id;
911 	} else {
912 		pr_debug("New link <%s> is standby\n", tipc_link_name(nl));
913 	}
914 
915 	/* Prepare synchronization with first link */
916 	tipc_link_tnl_prepare(ol, nl, SYNCH_MSG, xmitq);
917 }
918 
919 /**
920  * tipc_node_link_up - handle addition of link
921  * @n: target tipc_node
922  * @bearer_id: id of the bearer
923  * @xmitq: queue for messages to be xmited on
924  *
925  * Link becomes active (alone or shared) or standby, depending on its priority.
926  */
927 static void tipc_node_link_up(struct tipc_node *n, int bearer_id,
928 			      struct sk_buff_head *xmitq)
929 {
930 	struct tipc_media_addr *maddr;
931 
932 	tipc_node_write_lock(n);
933 	__tipc_node_link_up(n, bearer_id, xmitq);
934 	maddr = &n->links[bearer_id].maddr;
935 	tipc_bearer_xmit(n->net, bearer_id, xmitq, maddr, n);
936 	tipc_node_write_unlock(n);
937 }
938 
939 /**
940  * tipc_node_link_failover() - start failover in case "half-failover"
941  *
942  * This function is only called in a very special situation where link
943  * failover can be already started on peer node but not on this node.
944  * This can happen when e.g.::
945  *
946  *	1. Both links <1A-2A>, <1B-2B> down
947  *	2. Link endpoint 2A up, but 1A still down (e.g. due to network
948  *	disturbance, wrong session, etc.)
949  *	3. Link <1B-2B> up
950  *	4. Link endpoint 2A down (e.g. due to link tolerance timeout)
951  *	5. Node 2 starts failover onto link <1B-2B>
952  *
953  *	==> Node 1 does never start link/node failover!
954  *
955  * @n: tipc node structure
956  * @l: link peer endpoint failingover (- can be NULL)
957  * @tnl: tunnel link
958  * @xmitq: queue for messages to be xmited on tnl link later
959  */
960 static void tipc_node_link_failover(struct tipc_node *n, struct tipc_link *l,
961 				    struct tipc_link *tnl,
962 				    struct sk_buff_head *xmitq)
963 {
964 	/* Avoid to be "self-failover" that can never end */
965 	if (!tipc_link_is_up(tnl))
966 		return;
967 
968 	/* Don't rush, failure link may be in the process of resetting */
969 	if (l && !tipc_link_is_reset(l))
970 		return;
971 
972 	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
973 	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
974 
975 	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
976 	tipc_link_failover_prepare(l, tnl, xmitq);
977 
978 	if (l)
979 		tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
980 	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
981 }
982 
983 /**
984  * __tipc_node_link_down - handle loss of link
985  * @n: target tipc_node
986  * @bearer_id: id of the bearer
987  * @xmitq: queue for messages to be xmited on
988  * @maddr: output media address of the bearer
989  */
990 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
991 				  struct sk_buff_head *xmitq,
992 				  struct tipc_media_addr **maddr)
993 {
994 	struct tipc_link_entry *le = &n->links[*bearer_id];
995 	int *slot0 = &n->active_links[0];
996 	int *slot1 = &n->active_links[1];
997 	int i, highest = 0, prio;
998 	struct tipc_link *l, *_l, *tnl;
999 
1000 	l = n->links[*bearer_id].link;
1001 	if (!l || tipc_link_is_reset(l))
1002 		return;
1003 
1004 	n->working_links--;
1005 	n->action_flags |= TIPC_NOTIFY_LINK_DOWN;
1006 	n->link_id = tipc_link_id(l);
1007 
1008 	tipc_bearer_remove_dest(n->net, *bearer_id, n->addr);
1009 
1010 	pr_debug("Lost link <%s> on network plane %c\n",
1011 		 tipc_link_name(l), tipc_link_plane(l));
1012 
1013 	/* Select new active link if any available */
1014 	*slot0 = INVALID_BEARER_ID;
1015 	*slot1 = INVALID_BEARER_ID;
1016 	for (i = 0; i < MAX_BEARERS; i++) {
1017 		_l = n->links[i].link;
1018 		if (!_l || !tipc_link_is_up(_l))
1019 			continue;
1020 		if (_l == l)
1021 			continue;
1022 		prio = tipc_link_prio(_l);
1023 		if (prio < highest)
1024 			continue;
1025 		if (prio > highest) {
1026 			highest = prio;
1027 			*slot0 = i;
1028 			*slot1 = i;
1029 			continue;
1030 		}
1031 		*slot1 = i;
1032 	}
1033 
1034 	if (!node_is_up(n)) {
1035 		if (tipc_link_peer_is_down(l))
1036 			tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
1037 		tipc_node_fsm_evt(n, SELF_LOST_CONTACT_EVT);
1038 		trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down!");
1039 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1040 		tipc_link_reset(l);
1041 		tipc_link_build_reset_msg(l, xmitq);
1042 		*maddr = &n->links[*bearer_id].maddr;
1043 		node_lost_contact(n, &le->inputq);
1044 		tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
1045 		return;
1046 	}
1047 	tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
1048 
1049 	/* There is still a working link => initiate failover */
1050 	*bearer_id = n->active_links[0];
1051 	tnl = n->links[*bearer_id].link;
1052 	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
1053 	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
1054 	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
1055 	tipc_link_tnl_prepare(l, tnl, FAILOVER_MSG, xmitq);
1056 	trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down -> failover!");
1057 	tipc_link_reset(l);
1058 	tipc_link_fsm_evt(l, LINK_RESET_EVT);
1059 	tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
1060 	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
1061 	*maddr = &n->links[*bearer_id].maddr;
1062 }
1063 
1064 static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete)
1065 {
1066 	struct tipc_link_entry *le = &n->links[bearer_id];
1067 	struct tipc_media_addr *maddr = NULL;
1068 	struct tipc_link *l = le->link;
1069 	int old_bearer_id = bearer_id;
1070 	struct sk_buff_head xmitq;
1071 
1072 	if (!l)
1073 		return;
1074 
1075 	__skb_queue_head_init(&xmitq);
1076 
1077 	tipc_node_write_lock(n);
1078 	if (!tipc_link_is_establishing(l)) {
1079 		__tipc_node_link_down(n, &bearer_id, &xmitq, &maddr);
1080 	} else {
1081 		/* Defuse pending tipc_node_link_up() */
1082 		tipc_link_reset(l);
1083 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1084 	}
1085 	if (delete) {
1086 		kfree(l);
1087 		le->link = NULL;
1088 		n->link_cnt--;
1089 	}
1090 	trace_tipc_node_link_down(n, true, "node link down or deleted!");
1091 	tipc_node_write_unlock(n);
1092 	if (delete)
1093 		tipc_mon_remove_peer(n->net, n->addr, old_bearer_id);
1094 	if (!skb_queue_empty(&xmitq))
1095 		tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr, n);
1096 	tipc_sk_rcv(n->net, &le->inputq);
1097 }
1098 
1099 static bool node_is_up(struct tipc_node *n)
1100 {
1101 	return n->active_links[0] != INVALID_BEARER_ID;
1102 }
1103 
1104 bool tipc_node_is_up(struct net *net, u32 addr)
1105 {
1106 	struct tipc_node *n;
1107 	bool retval = false;
1108 
1109 	if (in_own_node(net, addr))
1110 		return true;
1111 
1112 	n = tipc_node_find(net, addr);
1113 	if (!n)
1114 		return false;
1115 	retval = node_is_up(n);
1116 	tipc_node_put(n);
1117 	return retval;
1118 }
1119 
1120 static u32 tipc_node_suggest_addr(struct net *net, u32 addr)
1121 {
1122 	struct tipc_node *n;
1123 
1124 	addr ^= tipc_net(net)->random;
1125 	while ((n = tipc_node_find(net, addr))) {
1126 		tipc_node_put(n);
1127 		addr++;
1128 	}
1129 	return addr;
1130 }
1131 
1132 /* tipc_node_try_addr(): Check if addr can be used by peer, suggest other if not
1133  * Returns suggested address if any, otherwise 0
1134  */
1135 u32 tipc_node_try_addr(struct net *net, u8 *id, u32 addr)
1136 {
1137 	struct tipc_net *tn = tipc_net(net);
1138 	struct tipc_node *n;
1139 	bool preliminary;
1140 	u32 sugg_addr;
1141 
1142 	/* Suggest new address if some other peer is using this one */
1143 	n = tipc_node_find(net, addr);
1144 	if (n) {
1145 		if (!memcmp(n->peer_id, id, NODE_ID_LEN))
1146 			addr = 0;
1147 		tipc_node_put(n);
1148 		if (!addr)
1149 			return 0;
1150 		return tipc_node_suggest_addr(net, addr);
1151 	}
1152 
1153 	/* Suggest previously used address if peer is known */
1154 	n = tipc_node_find_by_id(net, id);
1155 	if (n) {
1156 		sugg_addr = n->addr;
1157 		preliminary = n->preliminary;
1158 		tipc_node_put(n);
1159 		if (!preliminary)
1160 			return sugg_addr;
1161 	}
1162 
1163 	/* Even this node may be in conflict */
1164 	if (tn->trial_addr == addr)
1165 		return tipc_node_suggest_addr(net, addr);
1166 
1167 	return 0;
1168 }
1169 
1170 void tipc_node_check_dest(struct net *net, u32 addr,
1171 			  u8 *peer_id, struct tipc_bearer *b,
1172 			  u16 capabilities, u32 signature, u32 hash_mixes,
1173 			  struct tipc_media_addr *maddr,
1174 			  bool *respond, bool *dupl_addr)
1175 {
1176 	struct tipc_node *n;
1177 	struct tipc_link *l;
1178 	struct tipc_link_entry *le;
1179 	bool addr_match = false;
1180 	bool sign_match = false;
1181 	bool link_up = false;
1182 	bool link_is_reset = false;
1183 	bool accept_addr = false;
1184 	bool reset = false;
1185 	char *if_name;
1186 	unsigned long intv;
1187 	u16 session;
1188 
1189 	*dupl_addr = false;
1190 	*respond = false;
1191 
1192 	n = tipc_node_create(net, addr, peer_id, capabilities, hash_mixes,
1193 			     false);
1194 	if (!n)
1195 		return;
1196 
1197 	tipc_node_write_lock(n);
1198 
1199 	le = &n->links[b->identity];
1200 
1201 	/* Prepare to validate requesting node's signature and media address */
1202 	l = le->link;
1203 	link_up = l && tipc_link_is_up(l);
1204 	link_is_reset = l && tipc_link_is_reset(l);
1205 	addr_match = l && !memcmp(&le->maddr, maddr, sizeof(*maddr));
1206 	sign_match = (signature == n->signature);
1207 
1208 	/* These three flags give us eight permutations: */
1209 
1210 	if (sign_match && addr_match && link_up) {
1211 		/* All is fine. Ignore requests. */
1212 		/* Peer node is not a container/local namespace */
1213 		if (!n->peer_hash_mix)
1214 			n->peer_hash_mix = hash_mixes;
1215 	} else if (sign_match && addr_match && !link_up) {
1216 		/* Respond. The link will come up in due time */
1217 		*respond = true;
1218 	} else if (sign_match && !addr_match && link_up) {
1219 		/* Peer has changed i/f address without rebooting.
1220 		 * If so, the link will reset soon, and the next
1221 		 * discovery will be accepted. So we can ignore it.
1222 		 * It may also be a cloned or malicious peer having
1223 		 * chosen the same node address and signature as an
1224 		 * existing one.
1225 		 * Ignore requests until the link goes down, if ever.
1226 		 */
1227 		*dupl_addr = true;
1228 	} else if (sign_match && !addr_match && !link_up) {
1229 		/* Peer link has changed i/f address without rebooting.
1230 		 * It may also be a cloned or malicious peer; we can't
1231 		 * distinguish between the two.
1232 		 * The signature is correct, so we must accept.
1233 		 */
1234 		accept_addr = true;
1235 		*respond = true;
1236 		reset = true;
1237 	} else if (!sign_match && addr_match && link_up) {
1238 		/* Peer node rebooted. Two possibilities:
1239 		 *  - Delayed re-discovery; this link endpoint has already
1240 		 *    reset and re-established contact with the peer, before
1241 		 *    receiving a discovery message from that node.
1242 		 *    (The peer happened to receive one from this node first).
1243 		 *  - The peer came back so fast that our side has not
1244 		 *    discovered it yet. Probing from this side will soon
1245 		 *    reset the link, since there can be no working link
1246 		 *    endpoint at the peer end, and the link will re-establish.
1247 		 *  Accept the signature, since it comes from a known peer.
1248 		 */
1249 		n->signature = signature;
1250 	} else if (!sign_match && addr_match && !link_up) {
1251 		/*  The peer node has rebooted.
1252 		 *  Accept signature, since it is a known peer.
1253 		 */
1254 		n->signature = signature;
1255 		*respond = true;
1256 	} else if (!sign_match && !addr_match && link_up) {
1257 		/* Peer rebooted with new address, or a new/duplicate peer.
1258 		 * Ignore until the link goes down, if ever.
1259 		 */
1260 		*dupl_addr = true;
1261 	} else if (!sign_match && !addr_match && !link_up) {
1262 		/* Peer rebooted with new address, or it is a new peer.
1263 		 * Accept signature and address.
1264 		 */
1265 		n->signature = signature;
1266 		accept_addr = true;
1267 		*respond = true;
1268 		reset = true;
1269 	}
1270 
1271 	if (!accept_addr)
1272 		goto exit;
1273 
1274 	/* Now create new link if not already existing */
1275 	if (!l) {
1276 		if (n->link_cnt == 2)
1277 			goto exit;
1278 
1279 		if_name = strchr(b->name, ':') + 1;
1280 		get_random_bytes(&session, sizeof(u16));
1281 		if (!tipc_link_create(net, if_name, b->identity, b->tolerance,
1282 				      b->net_plane, b->mtu, b->priority,
1283 				      b->min_win, b->max_win, session,
1284 				      tipc_own_addr(net), addr, peer_id,
1285 				      n->capabilities,
1286 				      tipc_bc_sndlink(n->net), n->bc_entry.link,
1287 				      &le->inputq,
1288 				      &n->bc_entry.namedq, &l)) {
1289 			*respond = false;
1290 			goto exit;
1291 		}
1292 		trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link created!");
1293 		tipc_link_reset(l);
1294 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1295 		if (n->state == NODE_FAILINGOVER)
1296 			tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
1297 		link_is_reset = tipc_link_is_reset(l);
1298 		le->link = l;
1299 		n->link_cnt++;
1300 		tipc_node_calculate_timer(n, l);
1301 		if (n->link_cnt == 1) {
1302 			intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
1303 			if (!mod_timer(&n->timer, intv))
1304 				tipc_node_get(n);
1305 		}
1306 	}
1307 	memcpy(&le->maddr, maddr, sizeof(*maddr));
1308 exit:
1309 	tipc_node_write_unlock(n);
1310 	if (reset && !link_is_reset)
1311 		tipc_node_link_down(n, b->identity, false);
1312 	tipc_node_put(n);
1313 }
1314 
1315 void tipc_node_delete_links(struct net *net, int bearer_id)
1316 {
1317 	struct tipc_net *tn = net_generic(net, tipc_net_id);
1318 	struct tipc_node *n;
1319 
1320 	rcu_read_lock();
1321 	list_for_each_entry_rcu(n, &tn->node_list, list) {
1322 		tipc_node_link_down(n, bearer_id, true);
1323 	}
1324 	rcu_read_unlock();
1325 }
1326 
1327 static void tipc_node_reset_links(struct tipc_node *n)
1328 {
1329 	int i;
1330 
1331 	pr_warn("Resetting all links to %x\n", n->addr);
1332 
1333 	trace_tipc_node_reset_links(n, true, " ");
1334 	for (i = 0; i < MAX_BEARERS; i++) {
1335 		tipc_node_link_down(n, i, false);
1336 	}
1337 }
1338 
1339 /* tipc_node_fsm_evt - node finite state machine
1340  * Determines when contact is allowed with peer node
1341  */
1342 static void tipc_node_fsm_evt(struct tipc_node *n, int evt)
1343 {
1344 	int state = n->state;
1345 
1346 	switch (state) {
1347 	case SELF_DOWN_PEER_DOWN:
1348 		switch (evt) {
1349 		case SELF_ESTABL_CONTACT_EVT:
1350 			state = SELF_UP_PEER_COMING;
1351 			break;
1352 		case PEER_ESTABL_CONTACT_EVT:
1353 			state = SELF_COMING_PEER_UP;
1354 			break;
1355 		case SELF_LOST_CONTACT_EVT:
1356 		case PEER_LOST_CONTACT_EVT:
1357 			break;
1358 		case NODE_SYNCH_END_EVT:
1359 		case NODE_SYNCH_BEGIN_EVT:
1360 		case NODE_FAILOVER_BEGIN_EVT:
1361 		case NODE_FAILOVER_END_EVT:
1362 		default:
1363 			goto illegal_evt;
1364 		}
1365 		break;
1366 	case SELF_UP_PEER_UP:
1367 		switch (evt) {
1368 		case SELF_LOST_CONTACT_EVT:
1369 			state = SELF_DOWN_PEER_LEAVING;
1370 			break;
1371 		case PEER_LOST_CONTACT_EVT:
1372 			state = SELF_LEAVING_PEER_DOWN;
1373 			break;
1374 		case NODE_SYNCH_BEGIN_EVT:
1375 			state = NODE_SYNCHING;
1376 			break;
1377 		case NODE_FAILOVER_BEGIN_EVT:
1378 			state = NODE_FAILINGOVER;
1379 			break;
1380 		case SELF_ESTABL_CONTACT_EVT:
1381 		case PEER_ESTABL_CONTACT_EVT:
1382 		case NODE_SYNCH_END_EVT:
1383 		case NODE_FAILOVER_END_EVT:
1384 			break;
1385 		default:
1386 			goto illegal_evt;
1387 		}
1388 		break;
1389 	case SELF_DOWN_PEER_LEAVING:
1390 		switch (evt) {
1391 		case PEER_LOST_CONTACT_EVT:
1392 			state = SELF_DOWN_PEER_DOWN;
1393 			break;
1394 		case SELF_ESTABL_CONTACT_EVT:
1395 		case PEER_ESTABL_CONTACT_EVT:
1396 		case SELF_LOST_CONTACT_EVT:
1397 			break;
1398 		case NODE_SYNCH_END_EVT:
1399 		case NODE_SYNCH_BEGIN_EVT:
1400 		case NODE_FAILOVER_BEGIN_EVT:
1401 		case NODE_FAILOVER_END_EVT:
1402 		default:
1403 			goto illegal_evt;
1404 		}
1405 		break;
1406 	case SELF_UP_PEER_COMING:
1407 		switch (evt) {
1408 		case PEER_ESTABL_CONTACT_EVT:
1409 			state = SELF_UP_PEER_UP;
1410 			break;
1411 		case SELF_LOST_CONTACT_EVT:
1412 			state = SELF_DOWN_PEER_DOWN;
1413 			break;
1414 		case SELF_ESTABL_CONTACT_EVT:
1415 		case PEER_LOST_CONTACT_EVT:
1416 		case NODE_SYNCH_END_EVT:
1417 		case NODE_FAILOVER_BEGIN_EVT:
1418 			break;
1419 		case NODE_SYNCH_BEGIN_EVT:
1420 		case NODE_FAILOVER_END_EVT:
1421 		default:
1422 			goto illegal_evt;
1423 		}
1424 		break;
1425 	case SELF_COMING_PEER_UP:
1426 		switch (evt) {
1427 		case SELF_ESTABL_CONTACT_EVT:
1428 			state = SELF_UP_PEER_UP;
1429 			break;
1430 		case PEER_LOST_CONTACT_EVT:
1431 			state = SELF_DOWN_PEER_DOWN;
1432 			break;
1433 		case SELF_LOST_CONTACT_EVT:
1434 		case PEER_ESTABL_CONTACT_EVT:
1435 			break;
1436 		case NODE_SYNCH_END_EVT:
1437 		case NODE_SYNCH_BEGIN_EVT:
1438 		case NODE_FAILOVER_BEGIN_EVT:
1439 		case NODE_FAILOVER_END_EVT:
1440 		default:
1441 			goto illegal_evt;
1442 		}
1443 		break;
1444 	case SELF_LEAVING_PEER_DOWN:
1445 		switch (evt) {
1446 		case SELF_LOST_CONTACT_EVT:
1447 			state = SELF_DOWN_PEER_DOWN;
1448 			break;
1449 		case SELF_ESTABL_CONTACT_EVT:
1450 		case PEER_ESTABL_CONTACT_EVT:
1451 		case PEER_LOST_CONTACT_EVT:
1452 			break;
1453 		case NODE_SYNCH_END_EVT:
1454 		case NODE_SYNCH_BEGIN_EVT:
1455 		case NODE_FAILOVER_BEGIN_EVT:
1456 		case NODE_FAILOVER_END_EVT:
1457 		default:
1458 			goto illegal_evt;
1459 		}
1460 		break;
1461 	case NODE_FAILINGOVER:
1462 		switch (evt) {
1463 		case SELF_LOST_CONTACT_EVT:
1464 			state = SELF_DOWN_PEER_LEAVING;
1465 			break;
1466 		case PEER_LOST_CONTACT_EVT:
1467 			state = SELF_LEAVING_PEER_DOWN;
1468 			break;
1469 		case NODE_FAILOVER_END_EVT:
1470 			state = SELF_UP_PEER_UP;
1471 			break;
1472 		case NODE_FAILOVER_BEGIN_EVT:
1473 		case SELF_ESTABL_CONTACT_EVT:
1474 		case PEER_ESTABL_CONTACT_EVT:
1475 			break;
1476 		case NODE_SYNCH_BEGIN_EVT:
1477 		case NODE_SYNCH_END_EVT:
1478 		default:
1479 			goto illegal_evt;
1480 		}
1481 		break;
1482 	case NODE_SYNCHING:
1483 		switch (evt) {
1484 		case SELF_LOST_CONTACT_EVT:
1485 			state = SELF_DOWN_PEER_LEAVING;
1486 			break;
1487 		case PEER_LOST_CONTACT_EVT:
1488 			state = SELF_LEAVING_PEER_DOWN;
1489 			break;
1490 		case NODE_SYNCH_END_EVT:
1491 			state = SELF_UP_PEER_UP;
1492 			break;
1493 		case NODE_FAILOVER_BEGIN_EVT:
1494 			state = NODE_FAILINGOVER;
1495 			break;
1496 		case NODE_SYNCH_BEGIN_EVT:
1497 		case SELF_ESTABL_CONTACT_EVT:
1498 		case PEER_ESTABL_CONTACT_EVT:
1499 			break;
1500 		case NODE_FAILOVER_END_EVT:
1501 		default:
1502 			goto illegal_evt;
1503 		}
1504 		break;
1505 	default:
1506 		pr_err("Unknown node fsm state %x\n", state);
1507 		break;
1508 	}
1509 	trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
1510 	n->state = state;
1511 	return;
1512 
1513 illegal_evt:
1514 	pr_err("Illegal node fsm evt %x in state %x\n", evt, state);
1515 	trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
1516 }
1517 
1518 static void node_lost_contact(struct tipc_node *n,
1519 			      struct sk_buff_head *inputq)
1520 {
1521 	struct tipc_sock_conn *conn, *safe;
1522 	struct tipc_link *l;
1523 	struct list_head *conns = &n->conn_sks;
1524 	struct sk_buff *skb;
1525 	uint i;
1526 
1527 	pr_debug("Lost contact with %x\n", n->addr);
1528 	n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
1529 	trace_tipc_node_lost_contact(n, true, " ");
1530 
1531 	/* Clean up broadcast state */
1532 	tipc_bcast_remove_peer(n->net, n->bc_entry.link);
1533 	skb_queue_purge(&n->bc_entry.namedq);
1534 
1535 	/* Abort any ongoing link failover */
1536 	for (i = 0; i < MAX_BEARERS; i++) {
1537 		l = n->links[i].link;
1538 		if (l)
1539 			tipc_link_fsm_evt(l, LINK_FAILOVER_END_EVT);
1540 	}
1541 
1542 	/* Notify publications from this node */
1543 	n->action_flags |= TIPC_NOTIFY_NODE_DOWN;
1544 	n->peer_net = NULL;
1545 	n->peer_hash_mix = 0;
1546 	/* Notify sockets connected to node */
1547 	list_for_each_entry_safe(conn, safe, conns, list) {
1548 		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_CONN_MSG,
1549 				      SHORT_H_SIZE, 0, tipc_own_addr(n->net),
1550 				      conn->peer_node, conn->port,
1551 				      conn->peer_port, TIPC_ERR_NO_NODE);
1552 		if (likely(skb))
1553 			skb_queue_tail(inputq, skb);
1554 		list_del(&conn->list);
1555 		kfree(conn);
1556 	}
1557 }
1558 
1559 /**
1560  * tipc_node_get_linkname - get the name of a link
1561  *
1562  * @net: the applicable net namespace
1563  * @bearer_id: id of the bearer
1564  * @addr: peer node address
1565  * @linkname: link name output buffer
1566  * @len: size of @linkname output buffer
1567  *
1568  * Return: 0 on success
1569  */
1570 int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 addr,
1571 			   char *linkname, size_t len)
1572 {
1573 	struct tipc_link *link;
1574 	int err = -EINVAL;
1575 	struct tipc_node *node = tipc_node_find(net, addr);
1576 
1577 	if (!node)
1578 		return err;
1579 
1580 	if (bearer_id >= MAX_BEARERS)
1581 		goto exit;
1582 
1583 	tipc_node_read_lock(node);
1584 	link = node->links[bearer_id].link;
1585 	if (link) {
1586 		strncpy(linkname, tipc_link_name(link), len);
1587 		err = 0;
1588 	}
1589 	tipc_node_read_unlock(node);
1590 exit:
1591 	tipc_node_put(node);
1592 	return err;
1593 }
1594 
1595 /* Caller should hold node lock for the passed node */
1596 static int __tipc_nl_add_node(struct tipc_nl_msg *msg, struct tipc_node *node)
1597 {
1598 	void *hdr;
1599 	struct nlattr *attrs;
1600 
1601 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1602 			  NLM_F_MULTI, TIPC_NL_NODE_GET);
1603 	if (!hdr)
1604 		return -EMSGSIZE;
1605 
1606 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NODE);
1607 	if (!attrs)
1608 		goto msg_full;
1609 
1610 	if (nla_put_u32(msg->skb, TIPC_NLA_NODE_ADDR, node->addr))
1611 		goto attr_msg_full;
1612 	if (node_is_up(node))
1613 		if (nla_put_flag(msg->skb, TIPC_NLA_NODE_UP))
1614 			goto attr_msg_full;
1615 
1616 	nla_nest_end(msg->skb, attrs);
1617 	genlmsg_end(msg->skb, hdr);
1618 
1619 	return 0;
1620 
1621 attr_msg_full:
1622 	nla_nest_cancel(msg->skb, attrs);
1623 msg_full:
1624 	genlmsg_cancel(msg->skb, hdr);
1625 
1626 	return -EMSGSIZE;
1627 }
1628 
1629 static void tipc_lxc_xmit(struct net *peer_net, struct sk_buff_head *list)
1630 {
1631 	struct tipc_msg *hdr = buf_msg(skb_peek(list));
1632 	struct sk_buff_head inputq;
1633 
1634 	switch (msg_user(hdr)) {
1635 	case TIPC_LOW_IMPORTANCE:
1636 	case TIPC_MEDIUM_IMPORTANCE:
1637 	case TIPC_HIGH_IMPORTANCE:
1638 	case TIPC_CRITICAL_IMPORTANCE:
1639 		if (msg_connected(hdr) || msg_named(hdr) ||
1640 		    msg_direct(hdr)) {
1641 			tipc_loopback_trace(peer_net, list);
1642 			spin_lock_init(&list->lock);
1643 			tipc_sk_rcv(peer_net, list);
1644 			return;
1645 		}
1646 		if (msg_mcast(hdr)) {
1647 			tipc_loopback_trace(peer_net, list);
1648 			skb_queue_head_init(&inputq);
1649 			tipc_sk_mcast_rcv(peer_net, list, &inputq);
1650 			__skb_queue_purge(list);
1651 			skb_queue_purge(&inputq);
1652 			return;
1653 		}
1654 		return;
1655 	case MSG_FRAGMENTER:
1656 		if (tipc_msg_assemble(list)) {
1657 			tipc_loopback_trace(peer_net, list);
1658 			skb_queue_head_init(&inputq);
1659 			tipc_sk_mcast_rcv(peer_net, list, &inputq);
1660 			__skb_queue_purge(list);
1661 			skb_queue_purge(&inputq);
1662 		}
1663 		return;
1664 	case GROUP_PROTOCOL:
1665 	case CONN_MANAGER:
1666 		tipc_loopback_trace(peer_net, list);
1667 		spin_lock_init(&list->lock);
1668 		tipc_sk_rcv(peer_net, list);
1669 		return;
1670 	case LINK_PROTOCOL:
1671 	case NAME_DISTRIBUTOR:
1672 	case TUNNEL_PROTOCOL:
1673 	case BCAST_PROTOCOL:
1674 		return;
1675 	default:
1676 		return;
1677 	}
1678 }
1679 
1680 /**
1681  * tipc_node_xmit() - general link level function for message sending
1682  * @net: the applicable net namespace
1683  * @list: chain of buffers containing message
1684  * @dnode: address of destination node
1685  * @selector: a number used for deterministic link selection
1686  * Consumes the buffer chain.
1687  * Return: 0 if success, otherwise: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE,-ENOBUF
1688  */
1689 int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
1690 		   u32 dnode, int selector)
1691 {
1692 	struct tipc_link_entry *le = NULL;
1693 	struct tipc_node *n;
1694 	struct sk_buff_head xmitq;
1695 	bool node_up = false;
1696 	struct net *peer_net;
1697 	int bearer_id;
1698 	int rc;
1699 
1700 	if (in_own_node(net, dnode)) {
1701 		tipc_loopback_trace(net, list);
1702 		spin_lock_init(&list->lock);
1703 		tipc_sk_rcv(net, list);
1704 		return 0;
1705 	}
1706 
1707 	n = tipc_node_find(net, dnode);
1708 	if (unlikely(!n)) {
1709 		__skb_queue_purge(list);
1710 		return -EHOSTUNREACH;
1711 	}
1712 
1713 	rcu_read_lock();
1714 	tipc_node_read_lock(n);
1715 	node_up = node_is_up(n);
1716 	peer_net = n->peer_net;
1717 	tipc_node_read_unlock(n);
1718 	if (node_up && peer_net && check_net(peer_net)) {
1719 		/* xmit inner linux container */
1720 		tipc_lxc_xmit(peer_net, list);
1721 		if (likely(skb_queue_empty(list))) {
1722 			rcu_read_unlock();
1723 			tipc_node_put(n);
1724 			return 0;
1725 		}
1726 	}
1727 	rcu_read_unlock();
1728 
1729 	tipc_node_read_lock(n);
1730 	bearer_id = n->active_links[selector & 1];
1731 	if (unlikely(bearer_id == INVALID_BEARER_ID)) {
1732 		tipc_node_read_unlock(n);
1733 		tipc_node_put(n);
1734 		__skb_queue_purge(list);
1735 		return -EHOSTUNREACH;
1736 	}
1737 
1738 	__skb_queue_head_init(&xmitq);
1739 	le = &n->links[bearer_id];
1740 	spin_lock_bh(&le->lock);
1741 	rc = tipc_link_xmit(le->link, list, &xmitq);
1742 	spin_unlock_bh(&le->lock);
1743 	tipc_node_read_unlock(n);
1744 
1745 	if (unlikely(rc == -ENOBUFS))
1746 		tipc_node_link_down(n, bearer_id, false);
1747 	else
1748 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
1749 
1750 	tipc_node_put(n);
1751 
1752 	return rc;
1753 }
1754 
1755 /* tipc_node_xmit_skb(): send single buffer to destination
1756  * Buffers sent via this function are generally TIPC_SYSTEM_IMPORTANCE
1757  * messages, which will not be rejected
1758  * The only exception is datagram messages rerouted after secondary
1759  * lookup, which are rare and safe to dispose of anyway.
1760  */
1761 int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode,
1762 		       u32 selector)
1763 {
1764 	struct sk_buff_head head;
1765 
1766 	__skb_queue_head_init(&head);
1767 	__skb_queue_tail(&head, skb);
1768 	tipc_node_xmit(net, &head, dnode, selector);
1769 	return 0;
1770 }
1771 
1772 /* tipc_node_distr_xmit(): send single buffer msgs to individual destinations
1773  * Note: this is only for SYSTEM_IMPORTANCE messages, which cannot be rejected
1774  */
1775 int tipc_node_distr_xmit(struct net *net, struct sk_buff_head *xmitq)
1776 {
1777 	struct sk_buff *skb;
1778 	u32 selector, dnode;
1779 
1780 	while ((skb = __skb_dequeue(xmitq))) {
1781 		selector = msg_origport(buf_msg(skb));
1782 		dnode = msg_destnode(buf_msg(skb));
1783 		tipc_node_xmit_skb(net, skb, dnode, selector);
1784 	}
1785 	return 0;
1786 }
1787 
1788 void tipc_node_broadcast(struct net *net, struct sk_buff *skb, int rc_dests)
1789 {
1790 	struct sk_buff_head xmitq;
1791 	struct sk_buff *txskb;
1792 	struct tipc_node *n;
1793 	u16 dummy;
1794 	u32 dst;
1795 
1796 	/* Use broadcast if all nodes support it */
1797 	if (!rc_dests && tipc_bcast_get_mode(net) != BCLINK_MODE_RCAST) {
1798 		__skb_queue_head_init(&xmitq);
1799 		__skb_queue_tail(&xmitq, skb);
1800 		tipc_bcast_xmit(net, &xmitq, &dummy);
1801 		return;
1802 	}
1803 
1804 	/* Otherwise use legacy replicast method */
1805 	rcu_read_lock();
1806 	list_for_each_entry_rcu(n, tipc_nodes(net), list) {
1807 		dst = n->addr;
1808 		if (in_own_node(net, dst))
1809 			continue;
1810 		if (!node_is_up(n))
1811 			continue;
1812 		txskb = pskb_copy(skb, GFP_ATOMIC);
1813 		if (!txskb)
1814 			break;
1815 		msg_set_destnode(buf_msg(txskb), dst);
1816 		tipc_node_xmit_skb(net, txskb, dst, 0);
1817 	}
1818 	rcu_read_unlock();
1819 	kfree_skb(skb);
1820 }
1821 
1822 static void tipc_node_mcast_rcv(struct tipc_node *n)
1823 {
1824 	struct tipc_bclink_entry *be = &n->bc_entry;
1825 
1826 	/* 'arrvq' is under inputq2's lock protection */
1827 	spin_lock_bh(&be->inputq2.lock);
1828 	spin_lock_bh(&be->inputq1.lock);
1829 	skb_queue_splice_tail_init(&be->inputq1, &be->arrvq);
1830 	spin_unlock_bh(&be->inputq1.lock);
1831 	spin_unlock_bh(&be->inputq2.lock);
1832 	tipc_sk_mcast_rcv(n->net, &be->arrvq, &be->inputq2);
1833 }
1834 
1835 static void tipc_node_bc_sync_rcv(struct tipc_node *n, struct tipc_msg *hdr,
1836 				  int bearer_id, struct sk_buff_head *xmitq)
1837 {
1838 	struct tipc_link *ucl;
1839 	int rc;
1840 
1841 	rc = tipc_bcast_sync_rcv(n->net, n->bc_entry.link, hdr, xmitq);
1842 
1843 	if (rc & TIPC_LINK_DOWN_EVT) {
1844 		tipc_node_reset_links(n);
1845 		return;
1846 	}
1847 
1848 	if (!(rc & TIPC_LINK_SND_STATE))
1849 		return;
1850 
1851 	/* If probe message, a STATE response will be sent anyway */
1852 	if (msg_probe(hdr))
1853 		return;
1854 
1855 	/* Produce a STATE message carrying broadcast NACK */
1856 	tipc_node_read_lock(n);
1857 	ucl = n->links[bearer_id].link;
1858 	if (ucl)
1859 		tipc_link_build_state_msg(ucl, xmitq);
1860 	tipc_node_read_unlock(n);
1861 }
1862 
1863 /**
1864  * tipc_node_bc_rcv - process TIPC broadcast packet arriving from off-node
1865  * @net: the applicable net namespace
1866  * @skb: TIPC packet
1867  * @bearer_id: id of bearer message arrived on
1868  *
1869  * Invoked with no locks held.
1870  */
1871 static void tipc_node_bc_rcv(struct net *net, struct sk_buff *skb, int bearer_id)
1872 {
1873 	int rc;
1874 	struct sk_buff_head xmitq;
1875 	struct tipc_bclink_entry *be;
1876 	struct tipc_link_entry *le;
1877 	struct tipc_msg *hdr = buf_msg(skb);
1878 	int usr = msg_user(hdr);
1879 	u32 dnode = msg_destnode(hdr);
1880 	struct tipc_node *n;
1881 
1882 	__skb_queue_head_init(&xmitq);
1883 
1884 	/* If NACK for other node, let rcv link for that node peek into it */
1885 	if ((usr == BCAST_PROTOCOL) && (dnode != tipc_own_addr(net)))
1886 		n = tipc_node_find(net, dnode);
1887 	else
1888 		n = tipc_node_find(net, msg_prevnode(hdr));
1889 	if (!n) {
1890 		kfree_skb(skb);
1891 		return;
1892 	}
1893 	be = &n->bc_entry;
1894 	le = &n->links[bearer_id];
1895 
1896 	rc = tipc_bcast_rcv(net, be->link, skb);
1897 
1898 	/* Broadcast ACKs are sent on a unicast link */
1899 	if (rc & TIPC_LINK_SND_STATE) {
1900 		tipc_node_read_lock(n);
1901 		tipc_link_build_state_msg(le->link, &xmitq);
1902 		tipc_node_read_unlock(n);
1903 	}
1904 
1905 	if (!skb_queue_empty(&xmitq))
1906 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
1907 
1908 	if (!skb_queue_empty(&be->inputq1))
1909 		tipc_node_mcast_rcv(n);
1910 
1911 	/* Handle NAME_DISTRIBUTOR messages sent from 1.7 nodes */
1912 	if (!skb_queue_empty(&n->bc_entry.namedq))
1913 		tipc_named_rcv(net, &n->bc_entry.namedq,
1914 			       &n->bc_entry.named_rcv_nxt,
1915 			       &n->bc_entry.named_open);
1916 
1917 	/* If reassembly or retransmission failure => reset all links to peer */
1918 	if (rc & TIPC_LINK_DOWN_EVT)
1919 		tipc_node_reset_links(n);
1920 
1921 	tipc_node_put(n);
1922 }
1923 
1924 /**
1925  * tipc_node_check_state - check and if necessary update node state
1926  * @n: target tipc_node
1927  * @skb: TIPC packet
1928  * @bearer_id: identity of bearer delivering the packet
1929  * @xmitq: queue for messages to be xmited on
1930  * Return: true if state and msg are ok, otherwise false
1931  */
1932 static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
1933 				  int bearer_id, struct sk_buff_head *xmitq)
1934 {
1935 	struct tipc_msg *hdr = buf_msg(skb);
1936 	int usr = msg_user(hdr);
1937 	int mtyp = msg_type(hdr);
1938 	u16 oseqno = msg_seqno(hdr);
1939 	u16 exp_pkts = msg_msgcnt(hdr);
1940 	u16 rcv_nxt, syncpt, dlv_nxt, inputq_len;
1941 	int state = n->state;
1942 	struct tipc_link *l, *tnl, *pl = NULL;
1943 	struct tipc_media_addr *maddr;
1944 	int pb_id;
1945 
1946 	if (trace_tipc_node_check_state_enabled()) {
1947 		trace_tipc_skb_dump(skb, false, "skb for node state check");
1948 		trace_tipc_node_check_state(n, true, " ");
1949 	}
1950 	l = n->links[bearer_id].link;
1951 	if (!l)
1952 		return false;
1953 	rcv_nxt = tipc_link_rcv_nxt(l);
1954 
1955 
1956 	if (likely((state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL)))
1957 		return true;
1958 
1959 	/* Find parallel link, if any */
1960 	for (pb_id = 0; pb_id < MAX_BEARERS; pb_id++) {
1961 		if ((pb_id != bearer_id) && n->links[pb_id].link) {
1962 			pl = n->links[pb_id].link;
1963 			break;
1964 		}
1965 	}
1966 
1967 	if (!tipc_link_validate_msg(l, hdr)) {
1968 		trace_tipc_skb_dump(skb, false, "PROTO invalid (2)!");
1969 		trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (2)!");
1970 		return false;
1971 	}
1972 
1973 	/* Check and update node accesibility if applicable */
1974 	if (state == SELF_UP_PEER_COMING) {
1975 		if (!tipc_link_is_up(l))
1976 			return true;
1977 		if (!msg_peer_link_is_up(hdr))
1978 			return true;
1979 		tipc_node_fsm_evt(n, PEER_ESTABL_CONTACT_EVT);
1980 	}
1981 
1982 	if (state == SELF_DOWN_PEER_LEAVING) {
1983 		if (msg_peer_node_is_up(hdr))
1984 			return false;
1985 		tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
1986 		return true;
1987 	}
1988 
1989 	if (state == SELF_LEAVING_PEER_DOWN)
1990 		return false;
1991 
1992 	/* Ignore duplicate packets */
1993 	if ((usr != LINK_PROTOCOL) && less(oseqno, rcv_nxt))
1994 		return true;
1995 
1996 	/* Initiate or update failover mode if applicable */
1997 	if ((usr == TUNNEL_PROTOCOL) && (mtyp == FAILOVER_MSG)) {
1998 		syncpt = oseqno + exp_pkts - 1;
1999 		if (pl && !tipc_link_is_reset(pl)) {
2000 			__tipc_node_link_down(n, &pb_id, xmitq, &maddr);
2001 			trace_tipc_node_link_down(n, true,
2002 						  "node link down <- failover!");
2003 			tipc_skb_queue_splice_tail_init(tipc_link_inputq(pl),
2004 							tipc_link_inputq(l));
2005 		}
2006 
2007 		/* If parallel link was already down, and this happened before
2008 		 * the tunnel link came up, node failover was never started.
2009 		 * Ensure that a FAILOVER_MSG is sent to get peer out of
2010 		 * NODE_FAILINGOVER state, also this node must accept
2011 		 * TUNNEL_MSGs from peer.
2012 		 */
2013 		if (n->state != NODE_FAILINGOVER)
2014 			tipc_node_link_failover(n, pl, l, xmitq);
2015 
2016 		/* If pkts arrive out of order, use lowest calculated syncpt */
2017 		if (less(syncpt, n->sync_point))
2018 			n->sync_point = syncpt;
2019 	}
2020 
2021 	/* Open parallel link when tunnel link reaches synch point */
2022 	if ((n->state == NODE_FAILINGOVER) && tipc_link_is_up(l)) {
2023 		if (!more(rcv_nxt, n->sync_point))
2024 			return true;
2025 		tipc_node_fsm_evt(n, NODE_FAILOVER_END_EVT);
2026 		if (pl)
2027 			tipc_link_fsm_evt(pl, LINK_FAILOVER_END_EVT);
2028 		return true;
2029 	}
2030 
2031 	/* No syncing needed if only one link */
2032 	if (!pl || !tipc_link_is_up(pl))
2033 		return true;
2034 
2035 	/* Initiate synch mode if applicable */
2036 	if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG) && (oseqno == 1)) {
2037 		if (n->capabilities & TIPC_TUNNEL_ENHANCED)
2038 			syncpt = msg_syncpt(hdr);
2039 		else
2040 			syncpt = msg_seqno(msg_inner_hdr(hdr)) + exp_pkts - 1;
2041 		if (!tipc_link_is_up(l))
2042 			__tipc_node_link_up(n, bearer_id, xmitq);
2043 		if (n->state == SELF_UP_PEER_UP) {
2044 			n->sync_point = syncpt;
2045 			tipc_link_fsm_evt(l, LINK_SYNCH_BEGIN_EVT);
2046 			tipc_node_fsm_evt(n, NODE_SYNCH_BEGIN_EVT);
2047 		}
2048 	}
2049 
2050 	/* Open tunnel link when parallel link reaches synch point */
2051 	if (n->state == NODE_SYNCHING) {
2052 		if (tipc_link_is_synching(l)) {
2053 			tnl = l;
2054 		} else {
2055 			tnl = pl;
2056 			pl = l;
2057 		}
2058 		inputq_len = skb_queue_len(tipc_link_inputq(pl));
2059 		dlv_nxt = tipc_link_rcv_nxt(pl) - inputq_len;
2060 		if (more(dlv_nxt, n->sync_point)) {
2061 			tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
2062 			tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
2063 			return true;
2064 		}
2065 		if (l == pl)
2066 			return true;
2067 		if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG))
2068 			return true;
2069 		if (usr == LINK_PROTOCOL)
2070 			return true;
2071 		return false;
2072 	}
2073 	return true;
2074 }
2075 
2076 /**
2077  * tipc_rcv - process TIPC packets/messages arriving from off-node
2078  * @net: the applicable net namespace
2079  * @skb: TIPC packet
2080  * @b: pointer to bearer message arrived on
2081  *
2082  * Invoked with no locks held. Bearer pointer must point to a valid bearer
2083  * structure (i.e. cannot be NULL), but bearer can be inactive.
2084  */
2085 void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
2086 {
2087 	struct sk_buff_head xmitq;
2088 	struct tipc_link_entry *le;
2089 	struct tipc_msg *hdr;
2090 	struct tipc_node *n;
2091 	int bearer_id = b->identity;
2092 	u32 self = tipc_own_addr(net);
2093 	int usr, rc = 0;
2094 	u16 bc_ack;
2095 #ifdef CONFIG_TIPC_CRYPTO
2096 	struct tipc_ehdr *ehdr;
2097 
2098 	/* Check if message must be decrypted first */
2099 	if (TIPC_SKB_CB(skb)->decrypted || !tipc_ehdr_validate(skb))
2100 		goto rcv;
2101 
2102 	ehdr = (struct tipc_ehdr *)skb->data;
2103 	if (likely(ehdr->user != LINK_CONFIG)) {
2104 		n = tipc_node_find(net, ntohl(ehdr->addr));
2105 		if (unlikely(!n))
2106 			goto discard;
2107 	} else {
2108 		n = tipc_node_find_by_id(net, ehdr->id);
2109 	}
2110 	tipc_crypto_rcv(net, (n) ? n->crypto_rx : NULL, &skb, b);
2111 	if (!skb)
2112 		return;
2113 
2114 rcv:
2115 #endif
2116 	/* Ensure message is well-formed before touching the header */
2117 	if (unlikely(!tipc_msg_validate(&skb)))
2118 		goto discard;
2119 	__skb_queue_head_init(&xmitq);
2120 	hdr = buf_msg(skb);
2121 	usr = msg_user(hdr);
2122 	bc_ack = msg_bcast_ack(hdr);
2123 
2124 	/* Handle arrival of discovery or broadcast packet */
2125 	if (unlikely(msg_non_seq(hdr))) {
2126 		if (unlikely(usr == LINK_CONFIG))
2127 			return tipc_disc_rcv(net, skb, b);
2128 		else
2129 			return tipc_node_bc_rcv(net, skb, bearer_id);
2130 	}
2131 
2132 	/* Discard unicast link messages destined for another node */
2133 	if (unlikely(!msg_short(hdr) && (msg_destnode(hdr) != self)))
2134 		goto discard;
2135 
2136 	/* Locate neighboring node that sent packet */
2137 	n = tipc_node_find(net, msg_prevnode(hdr));
2138 	if (unlikely(!n))
2139 		goto discard;
2140 	le = &n->links[bearer_id];
2141 
2142 	/* Ensure broadcast reception is in synch with peer's send state */
2143 	if (unlikely(usr == LINK_PROTOCOL)) {
2144 		if (unlikely(skb_linearize(skb))) {
2145 			tipc_node_put(n);
2146 			goto discard;
2147 		}
2148 		hdr = buf_msg(skb);
2149 		tipc_node_bc_sync_rcv(n, hdr, bearer_id, &xmitq);
2150 	} else if (unlikely(tipc_link_acked(n->bc_entry.link) != bc_ack)) {
2151 		tipc_bcast_ack_rcv(net, n->bc_entry.link, hdr);
2152 	}
2153 
2154 	/* Receive packet directly if conditions permit */
2155 	tipc_node_read_lock(n);
2156 	if (likely((n->state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL))) {
2157 		spin_lock_bh(&le->lock);
2158 		if (le->link) {
2159 			rc = tipc_link_rcv(le->link, skb, &xmitq);
2160 			skb = NULL;
2161 		}
2162 		spin_unlock_bh(&le->lock);
2163 	}
2164 	tipc_node_read_unlock(n);
2165 
2166 	/* Check/update node state before receiving */
2167 	if (unlikely(skb)) {
2168 		if (unlikely(skb_linearize(skb)))
2169 			goto out_node_put;
2170 		tipc_node_write_lock(n);
2171 		if (tipc_node_check_state(n, skb, bearer_id, &xmitq)) {
2172 			if (le->link) {
2173 				rc = tipc_link_rcv(le->link, skb, &xmitq);
2174 				skb = NULL;
2175 			}
2176 		}
2177 		tipc_node_write_unlock(n);
2178 	}
2179 
2180 	if (unlikely(rc & TIPC_LINK_UP_EVT))
2181 		tipc_node_link_up(n, bearer_id, &xmitq);
2182 
2183 	if (unlikely(rc & TIPC_LINK_DOWN_EVT))
2184 		tipc_node_link_down(n, bearer_id, false);
2185 
2186 	if (unlikely(!skb_queue_empty(&n->bc_entry.namedq)))
2187 		tipc_named_rcv(net, &n->bc_entry.namedq,
2188 			       &n->bc_entry.named_rcv_nxt,
2189 			       &n->bc_entry.named_open);
2190 
2191 	if (unlikely(!skb_queue_empty(&n->bc_entry.inputq1)))
2192 		tipc_node_mcast_rcv(n);
2193 
2194 	if (!skb_queue_empty(&le->inputq))
2195 		tipc_sk_rcv(net, &le->inputq);
2196 
2197 	if (!skb_queue_empty(&xmitq))
2198 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
2199 
2200 out_node_put:
2201 	tipc_node_put(n);
2202 discard:
2203 	kfree_skb(skb);
2204 }
2205 
2206 void tipc_node_apply_property(struct net *net, struct tipc_bearer *b,
2207 			      int prop)
2208 {
2209 	struct tipc_net *tn = tipc_net(net);
2210 	int bearer_id = b->identity;
2211 	struct sk_buff_head xmitq;
2212 	struct tipc_link_entry *e;
2213 	struct tipc_node *n;
2214 
2215 	__skb_queue_head_init(&xmitq);
2216 
2217 	rcu_read_lock();
2218 
2219 	list_for_each_entry_rcu(n, &tn->node_list, list) {
2220 		tipc_node_write_lock(n);
2221 		e = &n->links[bearer_id];
2222 		if (e->link) {
2223 			if (prop == TIPC_NLA_PROP_TOL)
2224 				tipc_link_set_tolerance(e->link, b->tolerance,
2225 							&xmitq);
2226 			else if (prop == TIPC_NLA_PROP_MTU)
2227 				tipc_link_set_mtu(e->link, b->mtu);
2228 
2229 			/* Update MTU for node link entry */
2230 			e->mtu = tipc_link_mss(e->link);
2231 		}
2232 
2233 		tipc_node_write_unlock(n);
2234 		tipc_bearer_xmit(net, bearer_id, &xmitq, &e->maddr, NULL);
2235 	}
2236 
2237 	rcu_read_unlock();
2238 }
2239 
2240 int tipc_nl_peer_rm(struct sk_buff *skb, struct genl_info *info)
2241 {
2242 	struct net *net = sock_net(skb->sk);
2243 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2244 	struct nlattr *attrs[TIPC_NLA_NET_MAX + 1];
2245 	struct tipc_node *peer, *temp_node;
2246 	u8 node_id[NODE_ID_LEN];
2247 	u64 *w0 = (u64 *)&node_id[0];
2248 	u64 *w1 = (u64 *)&node_id[8];
2249 	u32 addr;
2250 	int err;
2251 
2252 	/* We identify the peer by its net */
2253 	if (!info->attrs[TIPC_NLA_NET])
2254 		return -EINVAL;
2255 
2256 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_NET_MAX,
2257 					  info->attrs[TIPC_NLA_NET],
2258 					  tipc_nl_net_policy, info->extack);
2259 	if (err)
2260 		return err;
2261 
2262 	/* attrs[TIPC_NLA_NET_NODEID] and attrs[TIPC_NLA_NET_ADDR] are
2263 	 * mutually exclusive cases
2264 	 */
2265 	if (attrs[TIPC_NLA_NET_ADDR]) {
2266 		addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]);
2267 		if (!addr)
2268 			return -EINVAL;
2269 	}
2270 
2271 	if (attrs[TIPC_NLA_NET_NODEID]) {
2272 		if (!attrs[TIPC_NLA_NET_NODEID_W1])
2273 			return -EINVAL;
2274 		*w0 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID]);
2275 		*w1 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID_W1]);
2276 		addr = hash128to32(node_id);
2277 	}
2278 
2279 	if (in_own_node(net, addr))
2280 		return -ENOTSUPP;
2281 
2282 	spin_lock_bh(&tn->node_list_lock);
2283 	peer = tipc_node_find(net, addr);
2284 	if (!peer) {
2285 		spin_unlock_bh(&tn->node_list_lock);
2286 		return -ENXIO;
2287 	}
2288 
2289 	tipc_node_write_lock(peer);
2290 	if (peer->state != SELF_DOWN_PEER_DOWN &&
2291 	    peer->state != SELF_DOWN_PEER_LEAVING) {
2292 		tipc_node_write_unlock(peer);
2293 		err = -EBUSY;
2294 		goto err_out;
2295 	}
2296 
2297 	tipc_node_clear_links(peer);
2298 	tipc_node_write_unlock(peer);
2299 	tipc_node_delete(peer);
2300 
2301 	/* Calculate cluster capabilities */
2302 	tn->capabilities = TIPC_NODE_CAPABILITIES;
2303 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
2304 		tn->capabilities &= temp_node->capabilities;
2305 	}
2306 	tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
2307 	err = 0;
2308 err_out:
2309 	tipc_node_put(peer);
2310 	spin_unlock_bh(&tn->node_list_lock);
2311 
2312 	return err;
2313 }
2314 
2315 int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb)
2316 {
2317 	int err;
2318 	struct net *net = sock_net(skb->sk);
2319 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2320 	int done = cb->args[0];
2321 	int last_addr = cb->args[1];
2322 	struct tipc_node *node;
2323 	struct tipc_nl_msg msg;
2324 
2325 	if (done)
2326 		return 0;
2327 
2328 	msg.skb = skb;
2329 	msg.portid = NETLINK_CB(cb->skb).portid;
2330 	msg.seq = cb->nlh->nlmsg_seq;
2331 
2332 	rcu_read_lock();
2333 	if (last_addr) {
2334 		node = tipc_node_find(net, last_addr);
2335 		if (!node) {
2336 			rcu_read_unlock();
2337 			/* We never set seq or call nl_dump_check_consistent()
2338 			 * this means that setting prev_seq here will cause the
2339 			 * consistence check to fail in the netlink callback
2340 			 * handler. Resulting in the NLMSG_DONE message having
2341 			 * the NLM_F_DUMP_INTR flag set if the node state
2342 			 * changed while we released the lock.
2343 			 */
2344 			cb->prev_seq = 1;
2345 			return -EPIPE;
2346 		}
2347 		tipc_node_put(node);
2348 	}
2349 
2350 	list_for_each_entry_rcu(node, &tn->node_list, list) {
2351 		if (node->preliminary)
2352 			continue;
2353 		if (last_addr) {
2354 			if (node->addr == last_addr)
2355 				last_addr = 0;
2356 			else
2357 				continue;
2358 		}
2359 
2360 		tipc_node_read_lock(node);
2361 		err = __tipc_nl_add_node(&msg, node);
2362 		if (err) {
2363 			last_addr = node->addr;
2364 			tipc_node_read_unlock(node);
2365 			goto out;
2366 		}
2367 
2368 		tipc_node_read_unlock(node);
2369 	}
2370 	done = 1;
2371 out:
2372 	cb->args[0] = done;
2373 	cb->args[1] = last_addr;
2374 	rcu_read_unlock();
2375 
2376 	return skb->len;
2377 }
2378 
2379 /* tipc_node_find_by_name - locate owner node of link by link's name
2380  * @net: the applicable net namespace
2381  * @name: pointer to link name string
2382  * @bearer_id: pointer to index in 'node->links' array where the link was found.
2383  *
2384  * Returns pointer to node owning the link, or 0 if no matching link is found.
2385  */
2386 static struct tipc_node *tipc_node_find_by_name(struct net *net,
2387 						const char *link_name,
2388 						unsigned int *bearer_id)
2389 {
2390 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2391 	struct tipc_link *l;
2392 	struct tipc_node *n;
2393 	struct tipc_node *found_node = NULL;
2394 	int i;
2395 
2396 	*bearer_id = 0;
2397 	rcu_read_lock();
2398 	list_for_each_entry_rcu(n, &tn->node_list, list) {
2399 		tipc_node_read_lock(n);
2400 		for (i = 0; i < MAX_BEARERS; i++) {
2401 			l = n->links[i].link;
2402 			if (l && !strcmp(tipc_link_name(l), link_name)) {
2403 				*bearer_id = i;
2404 				found_node = n;
2405 				break;
2406 			}
2407 		}
2408 		tipc_node_read_unlock(n);
2409 		if (found_node)
2410 			break;
2411 	}
2412 	rcu_read_unlock();
2413 
2414 	return found_node;
2415 }
2416 
2417 int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info)
2418 {
2419 	int err;
2420 	int res = 0;
2421 	int bearer_id;
2422 	char *name;
2423 	struct tipc_link *link;
2424 	struct tipc_node *node;
2425 	struct sk_buff_head xmitq;
2426 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2427 	struct net *net = sock_net(skb->sk);
2428 
2429 	__skb_queue_head_init(&xmitq);
2430 
2431 	if (!info->attrs[TIPC_NLA_LINK])
2432 		return -EINVAL;
2433 
2434 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2435 					  info->attrs[TIPC_NLA_LINK],
2436 					  tipc_nl_link_policy, info->extack);
2437 	if (err)
2438 		return err;
2439 
2440 	if (!attrs[TIPC_NLA_LINK_NAME])
2441 		return -EINVAL;
2442 
2443 	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2444 
2445 	if (strcmp(name, tipc_bclink_name) == 0)
2446 		return tipc_nl_bc_link_set(net, attrs);
2447 
2448 	node = tipc_node_find_by_name(net, name, &bearer_id);
2449 	if (!node)
2450 		return -EINVAL;
2451 
2452 	tipc_node_read_lock(node);
2453 
2454 	link = node->links[bearer_id].link;
2455 	if (!link) {
2456 		res = -EINVAL;
2457 		goto out;
2458 	}
2459 
2460 	if (attrs[TIPC_NLA_LINK_PROP]) {
2461 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
2462 
2463 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP], props);
2464 		if (err) {
2465 			res = err;
2466 			goto out;
2467 		}
2468 
2469 		if (props[TIPC_NLA_PROP_TOL]) {
2470 			u32 tol;
2471 
2472 			tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2473 			tipc_link_set_tolerance(link, tol, &xmitq);
2474 		}
2475 		if (props[TIPC_NLA_PROP_PRIO]) {
2476 			u32 prio;
2477 
2478 			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2479 			tipc_link_set_prio(link, prio, &xmitq);
2480 		}
2481 		if (props[TIPC_NLA_PROP_WIN]) {
2482 			u32 max_win;
2483 
2484 			max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2485 			tipc_link_set_queue_limits(link,
2486 						   tipc_link_min_win(link),
2487 						   max_win);
2488 		}
2489 	}
2490 
2491 out:
2492 	tipc_node_read_unlock(node);
2493 	tipc_bearer_xmit(net, bearer_id, &xmitq, &node->links[bearer_id].maddr,
2494 			 NULL);
2495 	return res;
2496 }
2497 
2498 int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info)
2499 {
2500 	struct net *net = genl_info_net(info);
2501 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2502 	struct tipc_nl_msg msg;
2503 	char *name;
2504 	int err;
2505 
2506 	msg.portid = info->snd_portid;
2507 	msg.seq = info->snd_seq;
2508 
2509 	if (!info->attrs[TIPC_NLA_LINK])
2510 		return -EINVAL;
2511 
2512 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2513 					  info->attrs[TIPC_NLA_LINK],
2514 					  tipc_nl_link_policy, info->extack);
2515 	if (err)
2516 		return err;
2517 
2518 	if (!attrs[TIPC_NLA_LINK_NAME])
2519 		return -EINVAL;
2520 
2521 	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2522 
2523 	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2524 	if (!msg.skb)
2525 		return -ENOMEM;
2526 
2527 	if (strcmp(name, tipc_bclink_name) == 0) {
2528 		err = tipc_nl_add_bc_link(net, &msg, tipc_net(net)->bcl);
2529 		if (err)
2530 			goto err_free;
2531 	} else {
2532 		int bearer_id;
2533 		struct tipc_node *node;
2534 		struct tipc_link *link;
2535 
2536 		node = tipc_node_find_by_name(net, name, &bearer_id);
2537 		if (!node) {
2538 			err = -EINVAL;
2539 			goto err_free;
2540 		}
2541 
2542 		tipc_node_read_lock(node);
2543 		link = node->links[bearer_id].link;
2544 		if (!link) {
2545 			tipc_node_read_unlock(node);
2546 			err = -EINVAL;
2547 			goto err_free;
2548 		}
2549 
2550 		err = __tipc_nl_add_link(net, &msg, link, 0);
2551 		tipc_node_read_unlock(node);
2552 		if (err)
2553 			goto err_free;
2554 	}
2555 
2556 	return genlmsg_reply(msg.skb, info);
2557 
2558 err_free:
2559 	nlmsg_free(msg.skb);
2560 	return err;
2561 }
2562 
2563 int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info)
2564 {
2565 	int err;
2566 	char *link_name;
2567 	unsigned int bearer_id;
2568 	struct tipc_link *link;
2569 	struct tipc_node *node;
2570 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2571 	struct net *net = sock_net(skb->sk);
2572 	struct tipc_net *tn = tipc_net(net);
2573 	struct tipc_link_entry *le;
2574 
2575 	if (!info->attrs[TIPC_NLA_LINK])
2576 		return -EINVAL;
2577 
2578 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2579 					  info->attrs[TIPC_NLA_LINK],
2580 					  tipc_nl_link_policy, info->extack);
2581 	if (err)
2582 		return err;
2583 
2584 	if (!attrs[TIPC_NLA_LINK_NAME])
2585 		return -EINVAL;
2586 
2587 	link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2588 
2589 	err = -EINVAL;
2590 	if (!strcmp(link_name, tipc_bclink_name)) {
2591 		err = tipc_bclink_reset_stats(net, tipc_bc_sndlink(net));
2592 		if (err)
2593 			return err;
2594 		return 0;
2595 	} else if (strstr(link_name, tipc_bclink_name)) {
2596 		rcu_read_lock();
2597 		list_for_each_entry_rcu(node, &tn->node_list, list) {
2598 			tipc_node_read_lock(node);
2599 			link = node->bc_entry.link;
2600 			if (link && !strcmp(link_name, tipc_link_name(link))) {
2601 				err = tipc_bclink_reset_stats(net, link);
2602 				tipc_node_read_unlock(node);
2603 				break;
2604 			}
2605 			tipc_node_read_unlock(node);
2606 		}
2607 		rcu_read_unlock();
2608 		return err;
2609 	}
2610 
2611 	node = tipc_node_find_by_name(net, link_name, &bearer_id);
2612 	if (!node)
2613 		return -EINVAL;
2614 
2615 	le = &node->links[bearer_id];
2616 	tipc_node_read_lock(node);
2617 	spin_lock_bh(&le->lock);
2618 	link = node->links[bearer_id].link;
2619 	if (!link) {
2620 		spin_unlock_bh(&le->lock);
2621 		tipc_node_read_unlock(node);
2622 		return -EINVAL;
2623 	}
2624 	tipc_link_reset_stats(link);
2625 	spin_unlock_bh(&le->lock);
2626 	tipc_node_read_unlock(node);
2627 	return 0;
2628 }
2629 
2630 /* Caller should hold node lock  */
2631 static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
2632 				    struct tipc_node *node, u32 *prev_link,
2633 				    bool bc_link)
2634 {
2635 	u32 i;
2636 	int err;
2637 
2638 	for (i = *prev_link; i < MAX_BEARERS; i++) {
2639 		*prev_link = i;
2640 
2641 		if (!node->links[i].link)
2642 			continue;
2643 
2644 		err = __tipc_nl_add_link(net, msg,
2645 					 node->links[i].link, NLM_F_MULTI);
2646 		if (err)
2647 			return err;
2648 	}
2649 
2650 	if (bc_link) {
2651 		*prev_link = i;
2652 		err = tipc_nl_add_bc_link(net, msg, node->bc_entry.link);
2653 		if (err)
2654 			return err;
2655 	}
2656 
2657 	*prev_link = 0;
2658 
2659 	return 0;
2660 }
2661 
2662 int tipc_nl_node_dump_link(struct sk_buff *skb, struct netlink_callback *cb)
2663 {
2664 	struct net *net = sock_net(skb->sk);
2665 	struct nlattr **attrs = genl_dumpit_info(cb)->attrs;
2666 	struct nlattr *link[TIPC_NLA_LINK_MAX + 1];
2667 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2668 	struct tipc_node *node;
2669 	struct tipc_nl_msg msg;
2670 	u32 prev_node = cb->args[0];
2671 	u32 prev_link = cb->args[1];
2672 	int done = cb->args[2];
2673 	bool bc_link = cb->args[3];
2674 	int err;
2675 
2676 	if (done)
2677 		return 0;
2678 
2679 	if (!prev_node) {
2680 		/* Check if broadcast-receiver links dumping is needed */
2681 		if (attrs && attrs[TIPC_NLA_LINK]) {
2682 			err = nla_parse_nested_deprecated(link,
2683 							  TIPC_NLA_LINK_MAX,
2684 							  attrs[TIPC_NLA_LINK],
2685 							  tipc_nl_link_policy,
2686 							  NULL);
2687 			if (unlikely(err))
2688 				return err;
2689 			if (unlikely(!link[TIPC_NLA_LINK_BROADCAST]))
2690 				return -EINVAL;
2691 			bc_link = true;
2692 		}
2693 	}
2694 
2695 	msg.skb = skb;
2696 	msg.portid = NETLINK_CB(cb->skb).portid;
2697 	msg.seq = cb->nlh->nlmsg_seq;
2698 
2699 	rcu_read_lock();
2700 	if (prev_node) {
2701 		node = tipc_node_find(net, prev_node);
2702 		if (!node) {
2703 			/* We never set seq or call nl_dump_check_consistent()
2704 			 * this means that setting prev_seq here will cause the
2705 			 * consistence check to fail in the netlink callback
2706 			 * handler. Resulting in the last NLMSG_DONE message
2707 			 * having the NLM_F_DUMP_INTR flag set.
2708 			 */
2709 			cb->prev_seq = 1;
2710 			goto out;
2711 		}
2712 		tipc_node_put(node);
2713 
2714 		list_for_each_entry_continue_rcu(node, &tn->node_list,
2715 						 list) {
2716 			tipc_node_read_lock(node);
2717 			err = __tipc_nl_add_node_links(net, &msg, node,
2718 						       &prev_link, bc_link);
2719 			tipc_node_read_unlock(node);
2720 			if (err)
2721 				goto out;
2722 
2723 			prev_node = node->addr;
2724 		}
2725 	} else {
2726 		err = tipc_nl_add_bc_link(net, &msg, tn->bcl);
2727 		if (err)
2728 			goto out;
2729 
2730 		list_for_each_entry_rcu(node, &tn->node_list, list) {
2731 			tipc_node_read_lock(node);
2732 			err = __tipc_nl_add_node_links(net, &msg, node,
2733 						       &prev_link, bc_link);
2734 			tipc_node_read_unlock(node);
2735 			if (err)
2736 				goto out;
2737 
2738 			prev_node = node->addr;
2739 		}
2740 	}
2741 	done = 1;
2742 out:
2743 	rcu_read_unlock();
2744 
2745 	cb->args[0] = prev_node;
2746 	cb->args[1] = prev_link;
2747 	cb->args[2] = done;
2748 	cb->args[3] = bc_link;
2749 
2750 	return skb->len;
2751 }
2752 
2753 int tipc_nl_node_set_monitor(struct sk_buff *skb, struct genl_info *info)
2754 {
2755 	struct nlattr *attrs[TIPC_NLA_MON_MAX + 1];
2756 	struct net *net = sock_net(skb->sk);
2757 	int err;
2758 
2759 	if (!info->attrs[TIPC_NLA_MON])
2760 		return -EINVAL;
2761 
2762 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_MON_MAX,
2763 					  info->attrs[TIPC_NLA_MON],
2764 					  tipc_nl_monitor_policy,
2765 					  info->extack);
2766 	if (err)
2767 		return err;
2768 
2769 	if (attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]) {
2770 		u32 val;
2771 
2772 		val = nla_get_u32(attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]);
2773 		err = tipc_nl_monitor_set_threshold(net, val);
2774 		if (err)
2775 			return err;
2776 	}
2777 
2778 	return 0;
2779 }
2780 
2781 static int __tipc_nl_add_monitor_prop(struct net *net, struct tipc_nl_msg *msg)
2782 {
2783 	struct nlattr *attrs;
2784 	void *hdr;
2785 	u32 val;
2786 
2787 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2788 			  0, TIPC_NL_MON_GET);
2789 	if (!hdr)
2790 		return -EMSGSIZE;
2791 
2792 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_MON);
2793 	if (!attrs)
2794 		goto msg_full;
2795 
2796 	val = tipc_nl_monitor_get_threshold(net);
2797 
2798 	if (nla_put_u32(msg->skb, TIPC_NLA_MON_ACTIVATION_THRESHOLD, val))
2799 		goto attr_msg_full;
2800 
2801 	nla_nest_end(msg->skb, attrs);
2802 	genlmsg_end(msg->skb, hdr);
2803 
2804 	return 0;
2805 
2806 attr_msg_full:
2807 	nla_nest_cancel(msg->skb, attrs);
2808 msg_full:
2809 	genlmsg_cancel(msg->skb, hdr);
2810 
2811 	return -EMSGSIZE;
2812 }
2813 
2814 int tipc_nl_node_get_monitor(struct sk_buff *skb, struct genl_info *info)
2815 {
2816 	struct net *net = sock_net(skb->sk);
2817 	struct tipc_nl_msg msg;
2818 	int err;
2819 
2820 	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2821 	if (!msg.skb)
2822 		return -ENOMEM;
2823 	msg.portid = info->snd_portid;
2824 	msg.seq = info->snd_seq;
2825 
2826 	err = __tipc_nl_add_monitor_prop(net, &msg);
2827 	if (err) {
2828 		nlmsg_free(msg.skb);
2829 		return err;
2830 	}
2831 
2832 	return genlmsg_reply(msg.skb, info);
2833 }
2834 
2835 int tipc_nl_node_dump_monitor(struct sk_buff *skb, struct netlink_callback *cb)
2836 {
2837 	struct net *net = sock_net(skb->sk);
2838 	u32 prev_bearer = cb->args[0];
2839 	struct tipc_nl_msg msg;
2840 	int bearer_id;
2841 	int err;
2842 
2843 	if (prev_bearer == MAX_BEARERS)
2844 		return 0;
2845 
2846 	msg.skb = skb;
2847 	msg.portid = NETLINK_CB(cb->skb).portid;
2848 	msg.seq = cb->nlh->nlmsg_seq;
2849 
2850 	rtnl_lock();
2851 	for (bearer_id = prev_bearer; bearer_id < MAX_BEARERS; bearer_id++) {
2852 		err = __tipc_nl_add_monitor(net, &msg, bearer_id);
2853 		if (err)
2854 			break;
2855 	}
2856 	rtnl_unlock();
2857 	cb->args[0] = bearer_id;
2858 
2859 	return skb->len;
2860 }
2861 
2862 int tipc_nl_node_dump_monitor_peer(struct sk_buff *skb,
2863 				   struct netlink_callback *cb)
2864 {
2865 	struct net *net = sock_net(skb->sk);
2866 	u32 prev_node = cb->args[1];
2867 	u32 bearer_id = cb->args[2];
2868 	int done = cb->args[0];
2869 	struct tipc_nl_msg msg;
2870 	int err;
2871 
2872 	if (!prev_node) {
2873 		struct nlattr **attrs = genl_dumpit_info(cb)->attrs;
2874 		struct nlattr *mon[TIPC_NLA_MON_MAX + 1];
2875 
2876 		if (!attrs[TIPC_NLA_MON])
2877 			return -EINVAL;
2878 
2879 		err = nla_parse_nested_deprecated(mon, TIPC_NLA_MON_MAX,
2880 						  attrs[TIPC_NLA_MON],
2881 						  tipc_nl_monitor_policy,
2882 						  NULL);
2883 		if (err)
2884 			return err;
2885 
2886 		if (!mon[TIPC_NLA_MON_REF])
2887 			return -EINVAL;
2888 
2889 		bearer_id = nla_get_u32(mon[TIPC_NLA_MON_REF]);
2890 
2891 		if (bearer_id >= MAX_BEARERS)
2892 			return -EINVAL;
2893 	}
2894 
2895 	if (done)
2896 		return 0;
2897 
2898 	msg.skb = skb;
2899 	msg.portid = NETLINK_CB(cb->skb).portid;
2900 	msg.seq = cb->nlh->nlmsg_seq;
2901 
2902 	rtnl_lock();
2903 	err = tipc_nl_add_monitor_peer(net, &msg, bearer_id, &prev_node);
2904 	if (!err)
2905 		done = 1;
2906 
2907 	rtnl_unlock();
2908 	cb->args[0] = done;
2909 	cb->args[1] = prev_node;
2910 	cb->args[2] = bearer_id;
2911 
2912 	return skb->len;
2913 }
2914 
2915 #ifdef CONFIG_TIPC_CRYPTO
2916 static int tipc_nl_retrieve_key(struct nlattr **attrs,
2917 				struct tipc_aead_key **pkey)
2918 {
2919 	struct nlattr *attr = attrs[TIPC_NLA_NODE_KEY];
2920 	struct tipc_aead_key *key;
2921 
2922 	if (!attr)
2923 		return -ENODATA;
2924 
2925 	if (nla_len(attr) < sizeof(*key))
2926 		return -EINVAL;
2927 	key = (struct tipc_aead_key *)nla_data(attr);
2928 	if (key->keylen > TIPC_AEAD_KEYLEN_MAX ||
2929 	    nla_len(attr) < tipc_aead_key_size(key))
2930 		return -EINVAL;
2931 
2932 	*pkey = key;
2933 	return 0;
2934 }
2935 
2936 static int tipc_nl_retrieve_nodeid(struct nlattr **attrs, u8 **node_id)
2937 {
2938 	struct nlattr *attr = attrs[TIPC_NLA_NODE_ID];
2939 
2940 	if (!attr)
2941 		return -ENODATA;
2942 
2943 	if (nla_len(attr) < TIPC_NODEID_LEN)
2944 		return -EINVAL;
2945 
2946 	*node_id = (u8 *)nla_data(attr);
2947 	return 0;
2948 }
2949 
2950 static int tipc_nl_retrieve_rekeying(struct nlattr **attrs, u32 *intv)
2951 {
2952 	struct nlattr *attr = attrs[TIPC_NLA_NODE_REKEYING];
2953 
2954 	if (!attr)
2955 		return -ENODATA;
2956 
2957 	*intv = nla_get_u32(attr);
2958 	return 0;
2959 }
2960 
2961 static int __tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
2962 {
2963 	struct nlattr *attrs[TIPC_NLA_NODE_MAX + 1];
2964 	struct net *net = sock_net(skb->sk);
2965 	struct tipc_crypto *tx = tipc_net(net)->crypto_tx, *c = tx;
2966 	struct tipc_node *n = NULL;
2967 	struct tipc_aead_key *ukey;
2968 	bool rekeying = true, master_key = false;
2969 	u8 *id, *own_id, mode;
2970 	u32 intv = 0;
2971 	int rc = 0;
2972 
2973 	if (!info->attrs[TIPC_NLA_NODE])
2974 		return -EINVAL;
2975 
2976 	rc = nla_parse_nested(attrs, TIPC_NLA_NODE_MAX,
2977 			      info->attrs[TIPC_NLA_NODE],
2978 			      tipc_nl_node_policy, info->extack);
2979 	if (rc)
2980 		return rc;
2981 
2982 	own_id = tipc_own_id(net);
2983 	if (!own_id) {
2984 		GENL_SET_ERR_MSG(info, "not found own node identity (set id?)");
2985 		return -EPERM;
2986 	}
2987 
2988 	rc = tipc_nl_retrieve_rekeying(attrs, &intv);
2989 	if (rc == -ENODATA)
2990 		rekeying = false;
2991 
2992 	rc = tipc_nl_retrieve_key(attrs, &ukey);
2993 	if (rc == -ENODATA && rekeying)
2994 		goto rekeying;
2995 	else if (rc)
2996 		return rc;
2997 
2998 	rc = tipc_aead_key_validate(ukey, info);
2999 	if (rc)
3000 		return rc;
3001 
3002 	rc = tipc_nl_retrieve_nodeid(attrs, &id);
3003 	switch (rc) {
3004 	case -ENODATA:
3005 		mode = CLUSTER_KEY;
3006 		master_key = !!(attrs[TIPC_NLA_NODE_KEY_MASTER]);
3007 		break;
3008 	case 0:
3009 		mode = PER_NODE_KEY;
3010 		if (memcmp(id, own_id, NODE_ID_LEN)) {
3011 			n = tipc_node_find_by_id(net, id) ?:
3012 				tipc_node_create(net, 0, id, 0xffffu, 0, true);
3013 			if (unlikely(!n))
3014 				return -ENOMEM;
3015 			c = n->crypto_rx;
3016 		}
3017 		break;
3018 	default:
3019 		return rc;
3020 	}
3021 
3022 	/* Initiate the TX/RX key */
3023 	rc = tipc_crypto_key_init(c, ukey, mode, master_key);
3024 	if (n)
3025 		tipc_node_put(n);
3026 
3027 	if (unlikely(rc < 0)) {
3028 		GENL_SET_ERR_MSG(info, "unable to initiate or attach new key");
3029 		return rc;
3030 	} else if (c == tx) {
3031 		/* Distribute TX key but not master one */
3032 		if (!master_key && tipc_crypto_key_distr(tx, rc, NULL))
3033 			GENL_SET_ERR_MSG(info, "failed to replicate new key");
3034 rekeying:
3035 		/* Schedule TX rekeying if needed */
3036 		tipc_crypto_rekeying_sched(tx, rekeying, intv);
3037 	}
3038 
3039 	return 0;
3040 }
3041 
3042 int tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
3043 {
3044 	int err;
3045 
3046 	rtnl_lock();
3047 	err = __tipc_nl_node_set_key(skb, info);
3048 	rtnl_unlock();
3049 
3050 	return err;
3051 }
3052 
3053 static int __tipc_nl_node_flush_key(struct sk_buff *skb,
3054 				    struct genl_info *info)
3055 {
3056 	struct net *net = sock_net(skb->sk);
3057 	struct tipc_net *tn = tipc_net(net);
3058 	struct tipc_node *n;
3059 
3060 	tipc_crypto_key_flush(tn->crypto_tx);
3061 	rcu_read_lock();
3062 	list_for_each_entry_rcu(n, &tn->node_list, list)
3063 		tipc_crypto_key_flush(n->crypto_rx);
3064 	rcu_read_unlock();
3065 
3066 	return 0;
3067 }
3068 
3069 int tipc_nl_node_flush_key(struct sk_buff *skb, struct genl_info *info)
3070 {
3071 	int err;
3072 
3073 	rtnl_lock();
3074 	err = __tipc_nl_node_flush_key(skb, info);
3075 	rtnl_unlock();
3076 
3077 	return err;
3078 }
3079 #endif
3080 
3081 /**
3082  * tipc_node_dump - dump TIPC node data
3083  * @n: tipc node to be dumped
3084  * @more: dump more?
3085  *        - false: dump only tipc node data
3086  *        - true: dump node link data as well
3087  * @buf: returned buffer of dump data in format
3088  */
3089 int tipc_node_dump(struct tipc_node *n, bool more, char *buf)
3090 {
3091 	int i = 0;
3092 	size_t sz = (more) ? NODE_LMAX : NODE_LMIN;
3093 
3094 	if (!n) {
3095 		i += scnprintf(buf, sz, "node data: (null)\n");
3096 		return i;
3097 	}
3098 
3099 	i += scnprintf(buf, sz, "node data: %x", n->addr);
3100 	i += scnprintf(buf + i, sz - i, " %x", n->state);
3101 	i += scnprintf(buf + i, sz - i, " %d", n->active_links[0]);
3102 	i += scnprintf(buf + i, sz - i, " %d", n->active_links[1]);
3103 	i += scnprintf(buf + i, sz - i, " %x", n->action_flags);
3104 	i += scnprintf(buf + i, sz - i, " %u", n->failover_sent);
3105 	i += scnprintf(buf + i, sz - i, " %u", n->sync_point);
3106 	i += scnprintf(buf + i, sz - i, " %d", n->link_cnt);
3107 	i += scnprintf(buf + i, sz - i, " %u", n->working_links);
3108 	i += scnprintf(buf + i, sz - i, " %x", n->capabilities);
3109 	i += scnprintf(buf + i, sz - i, " %lu\n", n->keepalive_intv);
3110 
3111 	if (!more)
3112 		return i;
3113 
3114 	i += scnprintf(buf + i, sz - i, "link_entry[0]:\n");
3115 	i += scnprintf(buf + i, sz - i, " mtu: %u\n", n->links[0].mtu);
3116 	i += scnprintf(buf + i, sz - i, " media: ");
3117 	i += tipc_media_addr_printf(buf + i, sz - i, &n->links[0].maddr);
3118 	i += scnprintf(buf + i, sz - i, "\n");
3119 	i += tipc_link_dump(n->links[0].link, TIPC_DUMP_NONE, buf + i);
3120 	i += scnprintf(buf + i, sz - i, " inputq: ");
3121 	i += tipc_list_dump(&n->links[0].inputq, false, buf + i);
3122 
3123 	i += scnprintf(buf + i, sz - i, "link_entry[1]:\n");
3124 	i += scnprintf(buf + i, sz - i, " mtu: %u\n", n->links[1].mtu);
3125 	i += scnprintf(buf + i, sz - i, " media: ");
3126 	i += tipc_media_addr_printf(buf + i, sz - i, &n->links[1].maddr);
3127 	i += scnprintf(buf + i, sz - i, "\n");
3128 	i += tipc_link_dump(n->links[1].link, TIPC_DUMP_NONE, buf + i);
3129 	i += scnprintf(buf + i, sz - i, " inputq: ");
3130 	i += tipc_list_dump(&n->links[1].inputq, false, buf + i);
3131 
3132 	i += scnprintf(buf + i, sz - i, "bclink:\n ");
3133 	i += tipc_link_dump(n->bc_entry.link, TIPC_DUMP_NONE, buf + i);
3134 
3135 	return i;
3136 }
3137 
3138 void tipc_node_pre_cleanup_net(struct net *exit_net)
3139 {
3140 	struct tipc_node *n;
3141 	struct tipc_net *tn;
3142 	struct net *tmp;
3143 
3144 	rcu_read_lock();
3145 	for_each_net_rcu(tmp) {
3146 		if (tmp == exit_net)
3147 			continue;
3148 		tn = tipc_net(tmp);
3149 		if (!tn)
3150 			continue;
3151 		spin_lock_bh(&tn->node_list_lock);
3152 		list_for_each_entry_rcu(n, &tn->node_list, list) {
3153 			if (!n->peer_net)
3154 				continue;
3155 			if (n->peer_net != exit_net)
3156 				continue;
3157 			tipc_node_write_lock(n);
3158 			n->peer_net = NULL;
3159 			n->peer_hash_mix = 0;
3160 			tipc_node_write_unlock_fast(n);
3161 			break;
3162 		}
3163 		spin_unlock_bh(&tn->node_list_lock);
3164 	}
3165 	rcu_read_unlock();
3166 }
3167