xref: /linux/net/tipc/node.c (revision dddf197f29ba5e47a476dde82bf542ca2e0d5e5e)
1 /*
2  * net/tipc/node.c: TIPC node management routines
3  *
4  * Copyright (c) 2000-2006, 2012-2016, Ericsson AB
5  * Copyright (c) 2005-2006, 2010-2014, Wind River Systems
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the names of the copyright holders nor the names of its
17  *    contributors may be used to endorse or promote products derived from
18  *    this software without specific prior written permission.
19  *
20  * Alternatively, this software may be distributed under the terms of the
21  * GNU General Public License ("GPL") version 2 as published by the Free
22  * Software Foundation.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34  * POSSIBILITY OF SUCH DAMAGE.
35  */
36 
37 #include "core.h"
38 #include "link.h"
39 #include "node.h"
40 #include "name_distr.h"
41 #include "socket.h"
42 #include "bcast.h"
43 #include "monitor.h"
44 #include "discover.h"
45 #include "netlink.h"
46 #include "trace.h"
47 #include "crypto.h"
48 
49 #define INVALID_NODE_SIG	0x10000
50 #define NODE_CLEANUP_AFTER	300000
51 
52 /* Flags used to take different actions according to flag type
53  * TIPC_NOTIFY_NODE_DOWN: notify node is down
54  * TIPC_NOTIFY_NODE_UP: notify node is up
55  * TIPC_DISTRIBUTE_NAME: publish or withdraw link state name type
56  */
57 enum {
58 	TIPC_NOTIFY_NODE_DOWN		= (1 << 3),
59 	TIPC_NOTIFY_NODE_UP		= (1 << 4),
60 	TIPC_NOTIFY_LINK_UP		= (1 << 6),
61 	TIPC_NOTIFY_LINK_DOWN		= (1 << 7)
62 };
63 
64 struct tipc_link_entry {
65 	struct tipc_link *link;
66 	spinlock_t lock; /* per link */
67 	u32 mtu;
68 	struct sk_buff_head inputq;
69 	struct tipc_media_addr maddr;
70 };
71 
72 struct tipc_bclink_entry {
73 	struct tipc_link *link;
74 	struct sk_buff_head inputq1;
75 	struct sk_buff_head arrvq;
76 	struct sk_buff_head inputq2;
77 	struct sk_buff_head namedq;
78 	u16 named_rcv_nxt;
79 	bool named_open;
80 };
81 
82 /**
83  * struct tipc_node - TIPC node structure
84  * @addr: network address of node
85  * @kref: reference counter to node object
86  * @lock: rwlock governing access to structure
87  * @net: the applicable net namespace
88  * @hash: links to adjacent nodes in unsorted hash chain
89  * @active_links: bearer ids of active links, used as index into links[] array
90  * @links: array containing references to all links to node
91  * @bc_entry: broadcast link entry
92  * @action_flags: bit mask of different types of node actions
93  * @state: connectivity state vs peer node
94  * @preliminary: a preliminary node or not
95  * @failover_sent: failover sent or not
96  * @sync_point: sequence number where synch/failover is finished
97  * @list: links to adjacent nodes in sorted list of cluster's nodes
98  * @working_links: number of working links to node (both active and standby)
99  * @link_cnt: number of links to node
100  * @capabilities: bitmap, indicating peer node's functional capabilities
101  * @signature: node instance identifier
102  * @link_id: local and remote bearer ids of changing link, if any
103  * @peer_id: 128-bit ID of peer
104  * @peer_id_string: ID string of peer
105  * @publ_list: list of publications
106  * @conn_sks: list of connections (FIXME)
107  * @timer: node's keepalive timer
108  * @keepalive_intv: keepalive interval in milliseconds
109  * @rcu: rcu struct for tipc_node
110  * @delete_at: indicates the time for deleting a down node
111  * @peer_net: peer's net namespace
112  * @peer_hash_mix: hash for this peer (FIXME)
113  * @crypto_rx: RX crypto handler
114  */
115 struct tipc_node {
116 	u32 addr;
117 	struct kref kref;
118 	rwlock_t lock;
119 	struct net *net;
120 	struct hlist_node hash;
121 	int active_links[2];
122 	struct tipc_link_entry links[MAX_BEARERS];
123 	struct tipc_bclink_entry bc_entry;
124 	int action_flags;
125 	struct list_head list;
126 	int state;
127 	bool preliminary;
128 	bool failover_sent;
129 	u16 sync_point;
130 	int link_cnt;
131 	u16 working_links;
132 	u16 capabilities;
133 	u32 signature;
134 	u32 link_id;
135 	u8 peer_id[16];
136 	char peer_id_string[NODE_ID_STR_LEN];
137 	struct list_head publ_list;
138 	struct list_head conn_sks;
139 	unsigned long keepalive_intv;
140 	struct timer_list timer;
141 	struct rcu_head rcu;
142 	unsigned long delete_at;
143 	struct net *peer_net;
144 	u32 peer_hash_mix;
145 #ifdef CONFIG_TIPC_CRYPTO
146 	struct tipc_crypto *crypto_rx;
147 #endif
148 };
149 
150 /* Node FSM states and events:
151  */
152 enum {
153 	SELF_DOWN_PEER_DOWN    = 0xdd,
154 	SELF_UP_PEER_UP        = 0xaa,
155 	SELF_DOWN_PEER_LEAVING = 0xd1,
156 	SELF_UP_PEER_COMING    = 0xac,
157 	SELF_COMING_PEER_UP    = 0xca,
158 	SELF_LEAVING_PEER_DOWN = 0x1d,
159 	NODE_FAILINGOVER       = 0xf0,
160 	NODE_SYNCHING          = 0xcc
161 };
162 
163 enum {
164 	SELF_ESTABL_CONTACT_EVT = 0xece,
165 	SELF_LOST_CONTACT_EVT   = 0x1ce,
166 	PEER_ESTABL_CONTACT_EVT = 0x9ece,
167 	PEER_LOST_CONTACT_EVT   = 0x91ce,
168 	NODE_FAILOVER_BEGIN_EVT = 0xfbe,
169 	NODE_FAILOVER_END_EVT   = 0xfee,
170 	NODE_SYNCH_BEGIN_EVT    = 0xcbe,
171 	NODE_SYNCH_END_EVT      = 0xcee
172 };
173 
174 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
175 				  struct sk_buff_head *xmitq,
176 				  struct tipc_media_addr **maddr);
177 static void tipc_node_link_down(struct tipc_node *n, int bearer_id,
178 				bool delete);
179 static void node_lost_contact(struct tipc_node *n, struct sk_buff_head *inputq);
180 static void tipc_node_delete(struct tipc_node *node);
181 static void tipc_node_timeout(struct timer_list *t);
182 static void tipc_node_fsm_evt(struct tipc_node *n, int evt);
183 static struct tipc_node *tipc_node_find(struct net *net, u32 addr);
184 static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id);
185 static bool node_is_up(struct tipc_node *n);
186 static void tipc_node_delete_from_list(struct tipc_node *node);
187 
188 struct tipc_sock_conn {
189 	u32 port;
190 	u32 peer_port;
191 	u32 peer_node;
192 	struct list_head list;
193 };
194 
195 static struct tipc_link *node_active_link(struct tipc_node *n, int sel)
196 {
197 	int bearer_id = n->active_links[sel & 1];
198 
199 	if (unlikely(bearer_id == INVALID_BEARER_ID))
200 		return NULL;
201 
202 	return n->links[bearer_id].link;
203 }
204 
205 int tipc_node_get_mtu(struct net *net, u32 addr, u32 sel, bool connected)
206 {
207 	struct tipc_node *n;
208 	int bearer_id;
209 	unsigned int mtu = MAX_MSG_SIZE;
210 
211 	n = tipc_node_find(net, addr);
212 	if (unlikely(!n))
213 		return mtu;
214 
215 	/* Allow MAX_MSG_SIZE when building connection oriented message
216 	 * if they are in the same core network
217 	 */
218 	if (n->peer_net && connected) {
219 		tipc_node_put(n);
220 		return mtu;
221 	}
222 
223 	bearer_id = n->active_links[sel & 1];
224 	if (likely(bearer_id != INVALID_BEARER_ID))
225 		mtu = n->links[bearer_id].mtu;
226 	tipc_node_put(n);
227 	return mtu;
228 }
229 
230 bool tipc_node_get_id(struct net *net, u32 addr, u8 *id)
231 {
232 	u8 *own_id = tipc_own_id(net);
233 	struct tipc_node *n;
234 
235 	if (!own_id)
236 		return true;
237 
238 	if (addr == tipc_own_addr(net)) {
239 		memcpy(id, own_id, TIPC_NODEID_LEN);
240 		return true;
241 	}
242 	n = tipc_node_find(net, addr);
243 	if (!n)
244 		return false;
245 
246 	memcpy(id, &n->peer_id, TIPC_NODEID_LEN);
247 	tipc_node_put(n);
248 	return true;
249 }
250 
251 u16 tipc_node_get_capabilities(struct net *net, u32 addr)
252 {
253 	struct tipc_node *n;
254 	u16 caps;
255 
256 	n = tipc_node_find(net, addr);
257 	if (unlikely(!n))
258 		return TIPC_NODE_CAPABILITIES;
259 	caps = n->capabilities;
260 	tipc_node_put(n);
261 	return caps;
262 }
263 
264 u32 tipc_node_get_addr(struct tipc_node *node)
265 {
266 	return (node) ? node->addr : 0;
267 }
268 
269 char *tipc_node_get_id_str(struct tipc_node *node)
270 {
271 	return node->peer_id_string;
272 }
273 
274 #ifdef CONFIG_TIPC_CRYPTO
275 /**
276  * tipc_node_crypto_rx - Retrieve crypto RX handle from node
277  * @__n: target tipc_node
278  * Note: node ref counter must be held first!
279  */
280 struct tipc_crypto *tipc_node_crypto_rx(struct tipc_node *__n)
281 {
282 	return (__n) ? __n->crypto_rx : NULL;
283 }
284 
285 struct tipc_crypto *tipc_node_crypto_rx_by_list(struct list_head *pos)
286 {
287 	return container_of(pos, struct tipc_node, list)->crypto_rx;
288 }
289 
290 struct tipc_crypto *tipc_node_crypto_rx_by_addr(struct net *net, u32 addr)
291 {
292 	struct tipc_node *n;
293 
294 	n = tipc_node_find(net, addr);
295 	return (n) ? n->crypto_rx : NULL;
296 }
297 #endif
298 
299 static void tipc_node_free(struct rcu_head *rp)
300 {
301 	struct tipc_node *n = container_of(rp, struct tipc_node, rcu);
302 
303 #ifdef CONFIG_TIPC_CRYPTO
304 	tipc_crypto_stop(&n->crypto_rx);
305 #endif
306 	kfree(n);
307 }
308 
309 static void tipc_node_kref_release(struct kref *kref)
310 {
311 	struct tipc_node *n = container_of(kref, struct tipc_node, kref);
312 
313 	kfree(n->bc_entry.link);
314 	call_rcu(&n->rcu, tipc_node_free);
315 }
316 
317 void tipc_node_put(struct tipc_node *node)
318 {
319 	kref_put(&node->kref, tipc_node_kref_release);
320 }
321 
322 void tipc_node_get(struct tipc_node *node)
323 {
324 	kref_get(&node->kref);
325 }
326 
327 /*
328  * tipc_node_find - locate specified node object, if it exists
329  */
330 static struct tipc_node *tipc_node_find(struct net *net, u32 addr)
331 {
332 	struct tipc_net *tn = tipc_net(net);
333 	struct tipc_node *node;
334 	unsigned int thash = tipc_hashfn(addr);
335 
336 	rcu_read_lock();
337 	hlist_for_each_entry_rcu(node, &tn->node_htable[thash], hash) {
338 		if (node->addr != addr || node->preliminary)
339 			continue;
340 		if (!kref_get_unless_zero(&node->kref))
341 			node = NULL;
342 		break;
343 	}
344 	rcu_read_unlock();
345 	return node;
346 }
347 
348 /* tipc_node_find_by_id - locate specified node object by its 128-bit id
349  * Note: this function is called only when a discovery request failed
350  * to find the node by its 32-bit id, and is not time critical
351  */
352 static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id)
353 {
354 	struct tipc_net *tn = tipc_net(net);
355 	struct tipc_node *n;
356 	bool found = false;
357 
358 	rcu_read_lock();
359 	list_for_each_entry_rcu(n, &tn->node_list, list) {
360 		read_lock_bh(&n->lock);
361 		if (!memcmp(id, n->peer_id, 16) &&
362 		    kref_get_unless_zero(&n->kref))
363 			found = true;
364 		read_unlock_bh(&n->lock);
365 		if (found)
366 			break;
367 	}
368 	rcu_read_unlock();
369 	return found ? n : NULL;
370 }
371 
372 static void tipc_node_read_lock(struct tipc_node *n)
373 	__acquires(n->lock)
374 {
375 	read_lock_bh(&n->lock);
376 }
377 
378 static void tipc_node_read_unlock(struct tipc_node *n)
379 	__releases(n->lock)
380 {
381 	read_unlock_bh(&n->lock);
382 }
383 
384 static void tipc_node_write_lock(struct tipc_node *n)
385 	__acquires(n->lock)
386 {
387 	write_lock_bh(&n->lock);
388 }
389 
390 static void tipc_node_write_unlock_fast(struct tipc_node *n)
391 	__releases(n->lock)
392 {
393 	write_unlock_bh(&n->lock);
394 }
395 
396 static void tipc_node_write_unlock(struct tipc_node *n)
397 	__releases(n->lock)
398 {
399 	struct tipc_socket_addr sk;
400 	struct net *net = n->net;
401 	u32 flags = n->action_flags;
402 	struct list_head *publ_list;
403 	struct tipc_uaddr ua;
404 	u32 bearer_id, node;
405 
406 	if (likely(!flags)) {
407 		write_unlock_bh(&n->lock);
408 		return;
409 	}
410 
411 	tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_NODE_SCOPE,
412 		   TIPC_LINK_STATE, n->addr, n->addr);
413 	sk.ref = n->link_id;
414 	sk.node = tipc_own_addr(net);
415 	node = n->addr;
416 	bearer_id = n->link_id & 0xffff;
417 	publ_list = &n->publ_list;
418 
419 	n->action_flags &= ~(TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP |
420 			     TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP);
421 
422 	write_unlock_bh(&n->lock);
423 
424 	if (flags & TIPC_NOTIFY_NODE_DOWN)
425 		tipc_publ_notify(net, publ_list, node, n->capabilities);
426 
427 	if (flags & TIPC_NOTIFY_NODE_UP)
428 		tipc_named_node_up(net, node, n->capabilities);
429 
430 	if (flags & TIPC_NOTIFY_LINK_UP) {
431 		tipc_mon_peer_up(net, node, bearer_id);
432 		tipc_nametbl_publish(net, &ua, &sk, sk.ref);
433 	}
434 	if (flags & TIPC_NOTIFY_LINK_DOWN) {
435 		tipc_mon_peer_down(net, node, bearer_id);
436 		tipc_nametbl_withdraw(net, &ua, &sk, sk.ref);
437 	}
438 }
439 
440 static void tipc_node_assign_peer_net(struct tipc_node *n, u32 hash_mixes)
441 {
442 	int net_id = tipc_netid(n->net);
443 	struct tipc_net *tn_peer;
444 	struct net *tmp;
445 	u32 hash_chk;
446 
447 	if (n->peer_net)
448 		return;
449 
450 	for_each_net_rcu(tmp) {
451 		tn_peer = tipc_net(tmp);
452 		if (!tn_peer)
453 			continue;
454 		/* Integrity checking whether node exists in namespace or not */
455 		if (tn_peer->net_id != net_id)
456 			continue;
457 		if (memcmp(n->peer_id, tn_peer->node_id, NODE_ID_LEN))
458 			continue;
459 		hash_chk = tipc_net_hash_mixes(tmp, tn_peer->random);
460 		if (hash_mixes ^ hash_chk)
461 			continue;
462 		n->peer_net = tmp;
463 		n->peer_hash_mix = hash_mixes;
464 		break;
465 	}
466 }
467 
468 struct tipc_node *tipc_node_create(struct net *net, u32 addr, u8 *peer_id,
469 				   u16 capabilities, u32 hash_mixes,
470 				   bool preliminary)
471 {
472 	struct tipc_net *tn = net_generic(net, tipc_net_id);
473 	struct tipc_link *l, *snd_l = tipc_bc_sndlink(net);
474 	struct tipc_node *n, *temp_node;
475 	unsigned long intv;
476 	int bearer_id;
477 	int i;
478 
479 	spin_lock_bh(&tn->node_list_lock);
480 	n = tipc_node_find(net, addr) ?:
481 		tipc_node_find_by_id(net, peer_id);
482 	if (n) {
483 		if (!n->preliminary)
484 			goto update;
485 		if (preliminary)
486 			goto exit;
487 		/* A preliminary node becomes "real" now, refresh its data */
488 		tipc_node_write_lock(n);
489 		if (!tipc_link_bc_create(net, tipc_own_addr(net), addr, peer_id, U16_MAX,
490 					 tipc_link_min_win(snd_l), tipc_link_max_win(snd_l),
491 					 n->capabilities, &n->bc_entry.inputq1,
492 					 &n->bc_entry.namedq, snd_l, &n->bc_entry.link)) {
493 			pr_warn("Broadcast rcv link refresh failed, no memory\n");
494 			tipc_node_write_unlock_fast(n);
495 			tipc_node_put(n);
496 			n = NULL;
497 			goto exit;
498 		}
499 		n->preliminary = false;
500 		n->addr = addr;
501 		hlist_del_rcu(&n->hash);
502 		hlist_add_head_rcu(&n->hash,
503 				   &tn->node_htable[tipc_hashfn(addr)]);
504 		list_del_rcu(&n->list);
505 		list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
506 			if (n->addr < temp_node->addr)
507 				break;
508 		}
509 		list_add_tail_rcu(&n->list, &temp_node->list);
510 		tipc_node_write_unlock_fast(n);
511 
512 update:
513 		if (n->peer_hash_mix ^ hash_mixes)
514 			tipc_node_assign_peer_net(n, hash_mixes);
515 		if (n->capabilities == capabilities)
516 			goto exit;
517 		/* Same node may come back with new capabilities */
518 		tipc_node_write_lock(n);
519 		n->capabilities = capabilities;
520 		for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
521 			l = n->links[bearer_id].link;
522 			if (l)
523 				tipc_link_update_caps(l, capabilities);
524 		}
525 		tipc_node_write_unlock_fast(n);
526 
527 		/* Calculate cluster capabilities */
528 		tn->capabilities = TIPC_NODE_CAPABILITIES;
529 		list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
530 			tn->capabilities &= temp_node->capabilities;
531 		}
532 
533 		tipc_bcast_toggle_rcast(net,
534 					(tn->capabilities & TIPC_BCAST_RCAST));
535 
536 		goto exit;
537 	}
538 	n = kzalloc_obj(*n, GFP_ATOMIC);
539 	if (!n) {
540 		pr_warn("Node creation failed, no memory\n");
541 		goto exit;
542 	}
543 	tipc_nodeid2string(n->peer_id_string, peer_id);
544 #ifdef CONFIG_TIPC_CRYPTO
545 	if (unlikely(tipc_crypto_start(&n->crypto_rx, net, n))) {
546 		pr_warn("Failed to start crypto RX(%s)!\n", n->peer_id_string);
547 		kfree(n);
548 		n = NULL;
549 		goto exit;
550 	}
551 #endif
552 	n->addr = addr;
553 	n->preliminary = preliminary;
554 	memcpy(&n->peer_id, peer_id, 16);
555 	n->net = net;
556 	n->peer_net = NULL;
557 	n->peer_hash_mix = 0;
558 	/* Assign kernel local namespace if exists */
559 	tipc_node_assign_peer_net(n, hash_mixes);
560 	n->capabilities = capabilities;
561 	kref_init(&n->kref);
562 	rwlock_init(&n->lock);
563 	INIT_HLIST_NODE(&n->hash);
564 	INIT_LIST_HEAD(&n->list);
565 	INIT_LIST_HEAD(&n->publ_list);
566 	INIT_LIST_HEAD(&n->conn_sks);
567 	skb_queue_head_init(&n->bc_entry.namedq);
568 	skb_queue_head_init(&n->bc_entry.inputq1);
569 	__skb_queue_head_init(&n->bc_entry.arrvq);
570 	skb_queue_head_init(&n->bc_entry.inputq2);
571 	for (i = 0; i < MAX_BEARERS; i++)
572 		spin_lock_init(&n->links[i].lock);
573 	n->state = SELF_DOWN_PEER_LEAVING;
574 	n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
575 	n->signature = INVALID_NODE_SIG;
576 	n->active_links[0] = INVALID_BEARER_ID;
577 	n->active_links[1] = INVALID_BEARER_ID;
578 	if (!preliminary &&
579 	    !tipc_link_bc_create(net, tipc_own_addr(net), addr, peer_id, U16_MAX,
580 				 tipc_link_min_win(snd_l), tipc_link_max_win(snd_l),
581 				 n->capabilities, &n->bc_entry.inputq1,
582 				 &n->bc_entry.namedq, snd_l, &n->bc_entry.link)) {
583 		pr_warn("Broadcast rcv link creation failed, no memory\n");
584 		tipc_node_put(n);
585 		n = NULL;
586 		goto exit;
587 	}
588 	tipc_node_get(n);
589 	timer_setup(&n->timer, tipc_node_timeout, 0);
590 	/* Start a slow timer anyway, crypto needs it */
591 	n->keepalive_intv = 10000;
592 	intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
593 	if (!mod_timer(&n->timer, intv))
594 		tipc_node_get(n);
595 	hlist_add_head_rcu(&n->hash, &tn->node_htable[tipc_hashfn(addr)]);
596 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
597 		if (n->addr < temp_node->addr)
598 			break;
599 	}
600 	list_add_tail_rcu(&n->list, &temp_node->list);
601 	/* Calculate cluster capabilities */
602 	tn->capabilities = TIPC_NODE_CAPABILITIES;
603 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
604 		tn->capabilities &= temp_node->capabilities;
605 	}
606 	tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
607 	trace_tipc_node_create(n, true, " ");
608 exit:
609 	spin_unlock_bh(&tn->node_list_lock);
610 	return n;
611 }
612 
613 static void tipc_node_calculate_timer(struct tipc_node *n, struct tipc_link *l)
614 {
615 	unsigned long tol = tipc_link_tolerance(l);
616 	unsigned long intv = ((tol / 4) > 500) ? 500 : tol / 4;
617 
618 	/* Link with lowest tolerance determines timer interval */
619 	if (intv < n->keepalive_intv)
620 		n->keepalive_intv = intv;
621 
622 	/* Ensure link's abort limit corresponds to current tolerance */
623 	tipc_link_set_abort_limit(l, tol / n->keepalive_intv);
624 }
625 
626 static void tipc_node_delete_from_list(struct tipc_node *node)
627 {
628 #ifdef CONFIG_TIPC_CRYPTO
629 	tipc_crypto_key_flush(node->crypto_rx);
630 #endif
631 	list_del_rcu(&node->list);
632 	hlist_del_rcu(&node->hash);
633 	tipc_node_put(node);
634 }
635 
636 static void tipc_node_delete(struct tipc_node *node)
637 {
638 	trace_tipc_node_delete(node, true, " ");
639 	tipc_node_delete_from_list(node);
640 
641 	timer_delete_sync(&node->timer);
642 	tipc_node_put(node);
643 }
644 
645 void tipc_node_stop(struct net *net)
646 {
647 	struct tipc_net *tn = tipc_net(net);
648 	struct tipc_node *node, *t_node;
649 
650 	spin_lock_bh(&tn->node_list_lock);
651 	list_for_each_entry_safe(node, t_node, &tn->node_list, list)
652 		tipc_node_delete(node);
653 	spin_unlock_bh(&tn->node_list_lock);
654 }
655 
656 void tipc_node_subscribe(struct net *net, struct list_head *subscr, u32 addr)
657 {
658 	struct tipc_node *n;
659 
660 	if (in_own_node(net, addr))
661 		return;
662 
663 	n = tipc_node_find(net, addr);
664 	if (!n) {
665 		pr_warn("Node subscribe rejected, unknown node 0x%x\n", addr);
666 		return;
667 	}
668 	tipc_node_write_lock(n);
669 	list_add_tail(subscr, &n->publ_list);
670 	tipc_node_write_unlock_fast(n);
671 	tipc_node_put(n);
672 }
673 
674 void tipc_node_unsubscribe(struct net *net, struct list_head *subscr, u32 addr)
675 {
676 	struct tipc_node *n;
677 
678 	if (in_own_node(net, addr))
679 		return;
680 
681 	n = tipc_node_find(net, addr);
682 	if (!n) {
683 		pr_warn("Node unsubscribe rejected, unknown node 0x%x\n", addr);
684 		return;
685 	}
686 	tipc_node_write_lock(n);
687 	list_del_init(subscr);
688 	tipc_node_write_unlock_fast(n);
689 	tipc_node_put(n);
690 }
691 
692 int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port)
693 {
694 	struct tipc_node *node;
695 	struct tipc_sock_conn *conn;
696 	int err = 0;
697 
698 	if (in_own_node(net, dnode))
699 		return 0;
700 
701 	node = tipc_node_find(net, dnode);
702 	if (!node) {
703 		pr_warn("Connecting sock to node 0x%x failed\n", dnode);
704 		return -EHOSTUNREACH;
705 	}
706 	conn = kmalloc_obj(*conn, GFP_ATOMIC);
707 	if (!conn) {
708 		err = -EHOSTUNREACH;
709 		goto exit;
710 	}
711 	conn->peer_node = dnode;
712 	conn->port = port;
713 	conn->peer_port = peer_port;
714 
715 	tipc_node_write_lock(node);
716 	list_add_tail(&conn->list, &node->conn_sks);
717 	tipc_node_write_unlock(node);
718 exit:
719 	tipc_node_put(node);
720 	return err;
721 }
722 
723 void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port)
724 {
725 	struct tipc_node *node;
726 	struct tipc_sock_conn *conn, *safe;
727 
728 	if (in_own_node(net, dnode))
729 		return;
730 
731 	node = tipc_node_find(net, dnode);
732 	if (!node)
733 		return;
734 
735 	tipc_node_write_lock(node);
736 	list_for_each_entry_safe(conn, safe, &node->conn_sks, list) {
737 		if (port != conn->port)
738 			continue;
739 		list_del(&conn->list);
740 		kfree(conn);
741 	}
742 	tipc_node_write_unlock(node);
743 	tipc_node_put(node);
744 }
745 
746 static void  tipc_node_clear_links(struct tipc_node *node)
747 {
748 	int i;
749 
750 	for (i = 0; i < MAX_BEARERS; i++) {
751 		struct tipc_link_entry *le = &node->links[i];
752 
753 		if (le->link) {
754 			kfree(le->link);
755 			le->link = NULL;
756 			node->link_cnt--;
757 		}
758 	}
759 }
760 
761 /* tipc_node_cleanup - delete nodes that does not
762  * have active links for NODE_CLEANUP_AFTER time
763  */
764 static bool tipc_node_cleanup(struct tipc_node *peer)
765 {
766 	struct tipc_node *temp_node;
767 	struct tipc_net *tn = tipc_net(peer->net);
768 	bool deleted = false;
769 
770 	/* If lock held by tipc_node_stop() the node will be deleted anyway */
771 	if (!spin_trylock_bh(&tn->node_list_lock))
772 		return false;
773 
774 	tipc_node_write_lock(peer);
775 
776 	if (!node_is_up(peer) && time_after(jiffies, peer->delete_at)) {
777 		tipc_node_clear_links(peer);
778 		tipc_node_delete_from_list(peer);
779 		deleted = true;
780 	}
781 	tipc_node_write_unlock(peer);
782 
783 	if (!deleted) {
784 		spin_unlock_bh(&tn->node_list_lock);
785 		return deleted;
786 	}
787 
788 	/* Calculate cluster capabilities */
789 	tn->capabilities = TIPC_NODE_CAPABILITIES;
790 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
791 		tn->capabilities &= temp_node->capabilities;
792 	}
793 	tipc_bcast_toggle_rcast(peer->net,
794 				(tn->capabilities & TIPC_BCAST_RCAST));
795 	spin_unlock_bh(&tn->node_list_lock);
796 	return deleted;
797 }
798 
799 /* tipc_node_timeout - handle expiration of node timer
800  */
801 static void tipc_node_timeout(struct timer_list *t)
802 {
803 	struct tipc_node *n = timer_container_of(n, t, timer);
804 	struct tipc_link_entry *le;
805 	struct sk_buff_head xmitq;
806 	int remains = n->link_cnt;
807 	int bearer_id;
808 	int rc = 0;
809 
810 	trace_tipc_node_timeout(n, false, " ");
811 	if (!node_is_up(n) && tipc_node_cleanup(n)) {
812 		/*Removing the reference of Timer*/
813 		tipc_node_put(n);
814 		return;
815 	}
816 
817 #ifdef CONFIG_TIPC_CRYPTO
818 	/* Take any crypto key related actions first */
819 	tipc_crypto_timeout(n->crypto_rx);
820 #endif
821 	__skb_queue_head_init(&xmitq);
822 
823 	/* Initial node interval to value larger (10 seconds), then it will be
824 	 * recalculated with link lowest tolerance
825 	 */
826 	tipc_node_read_lock(n);
827 	n->keepalive_intv = 10000;
828 	tipc_node_read_unlock(n);
829 	for (bearer_id = 0; remains && (bearer_id < MAX_BEARERS); bearer_id++) {
830 		tipc_node_read_lock(n);
831 		le = &n->links[bearer_id];
832 		if (le->link) {
833 			spin_lock_bh(&le->lock);
834 			/* Link tolerance may change asynchronously: */
835 			tipc_node_calculate_timer(n, le->link);
836 			rc = tipc_link_timeout(le->link, &xmitq);
837 			spin_unlock_bh(&le->lock);
838 			remains--;
839 		}
840 		tipc_node_read_unlock(n);
841 		tipc_bearer_xmit(n->net, bearer_id, &xmitq, &le->maddr, n);
842 		if (rc & TIPC_LINK_DOWN_EVT)
843 			tipc_node_link_down(n, bearer_id, false);
844 	}
845 	mod_timer(&n->timer, jiffies + msecs_to_jiffies(n->keepalive_intv));
846 }
847 
848 /**
849  * __tipc_node_link_up - handle addition of link
850  * @n: target tipc_node
851  * @bearer_id: id of the bearer
852  * @xmitq: queue for messages to be xmited on
853  * Node lock must be held by caller
854  * Link becomes active (alone or shared) or standby, depending on its priority.
855  */
856 static void __tipc_node_link_up(struct tipc_node *n, int bearer_id,
857 				struct sk_buff_head *xmitq)
858 {
859 	int *slot0 = &n->active_links[0];
860 	int *slot1 = &n->active_links[1];
861 	struct tipc_link *ol = node_active_link(n, 0);
862 	struct tipc_link *nl = n->links[bearer_id].link;
863 
864 	if (!nl || tipc_link_is_up(nl))
865 		return;
866 
867 	tipc_link_fsm_evt(nl, LINK_ESTABLISH_EVT);
868 	if (!tipc_link_is_up(nl))
869 		return;
870 
871 	n->working_links++;
872 	n->action_flags |= TIPC_NOTIFY_LINK_UP;
873 	n->link_id = tipc_link_id(nl);
874 
875 	/* Leave room for tunnel header when returning 'mtu' to users: */
876 	n->links[bearer_id].mtu = tipc_link_mss(nl);
877 
878 	tipc_bearer_add_dest(n->net, bearer_id, n->addr);
879 	tipc_bcast_inc_bearer_dst_cnt(n->net, bearer_id);
880 
881 	pr_debug("Established link <%s> on network plane %c\n",
882 		 tipc_link_name(nl), tipc_link_plane(nl));
883 	trace_tipc_node_link_up(n, true, " ");
884 
885 	/* Ensure that a STATE message goes first */
886 	tipc_link_build_state_msg(nl, xmitq);
887 
888 	/* First link? => give it both slots */
889 	if (!ol) {
890 		*slot0 = bearer_id;
891 		*slot1 = bearer_id;
892 		tipc_node_fsm_evt(n, SELF_ESTABL_CONTACT_EVT);
893 		n->action_flags |= TIPC_NOTIFY_NODE_UP;
894 		tipc_link_set_active(nl, true);
895 		tipc_bcast_add_peer(n->net, nl, xmitq);
896 		return;
897 	}
898 
899 	/* Second link => redistribute slots */
900 	if (tipc_link_prio(nl) > tipc_link_prio(ol)) {
901 		pr_debug("Old link <%s> becomes standby\n", tipc_link_name(ol));
902 		*slot0 = bearer_id;
903 		*slot1 = bearer_id;
904 		tipc_link_set_active(nl, true);
905 		tipc_link_set_active(ol, false);
906 	} else if (tipc_link_prio(nl) == tipc_link_prio(ol)) {
907 		tipc_link_set_active(nl, true);
908 		*slot1 = bearer_id;
909 	} else {
910 		pr_debug("New link <%s> is standby\n", tipc_link_name(nl));
911 	}
912 
913 	/* Prepare synchronization with first link */
914 	tipc_link_tnl_prepare(ol, nl, SYNCH_MSG, xmitq);
915 }
916 
917 /**
918  * tipc_node_link_up - handle addition of link
919  * @n: target tipc_node
920  * @bearer_id: id of the bearer
921  * @xmitq: queue for messages to be xmited on
922  *
923  * Link becomes active (alone or shared) or standby, depending on its priority.
924  */
925 static void tipc_node_link_up(struct tipc_node *n, int bearer_id,
926 			      struct sk_buff_head *xmitq)
927 {
928 	struct tipc_media_addr *maddr;
929 
930 	tipc_node_write_lock(n);
931 	__tipc_node_link_up(n, bearer_id, xmitq);
932 	maddr = &n->links[bearer_id].maddr;
933 	tipc_bearer_xmit(n->net, bearer_id, xmitq, maddr, n);
934 	tipc_node_write_unlock(n);
935 }
936 
937 /**
938  * tipc_node_link_failover() - start failover in case "half-failover"
939  *
940  * This function is only called in a very special situation where link
941  * failover can be already started on peer node but not on this node.
942  * This can happen when e.g.::
943  *
944  *	1. Both links <1A-2A>, <1B-2B> down
945  *	2. Link endpoint 2A up, but 1A still down (e.g. due to network
946  *	disturbance, wrong session, etc.)
947  *	3. Link <1B-2B> up
948  *	4. Link endpoint 2A down (e.g. due to link tolerance timeout)
949  *	5. Node 2 starts failover onto link <1B-2B>
950  *
951  *	==> Node 1 does never start link/node failover!
952  *
953  * @n: tipc node structure
954  * @l: link peer endpoint failingover (- can be NULL)
955  * @tnl: tunnel link
956  * @xmitq: queue for messages to be xmited on tnl link later
957  */
958 static void tipc_node_link_failover(struct tipc_node *n, struct tipc_link *l,
959 				    struct tipc_link *tnl,
960 				    struct sk_buff_head *xmitq)
961 {
962 	/* Avoid to be "self-failover" that can never end */
963 	if (!tipc_link_is_up(tnl))
964 		return;
965 
966 	/* Don't rush, failure link may be in the process of resetting */
967 	if (l && !tipc_link_is_reset(l))
968 		return;
969 
970 	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
971 	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
972 
973 	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
974 	tipc_link_failover_prepare(l, tnl, xmitq);
975 
976 	if (l)
977 		tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
978 	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
979 }
980 
981 /**
982  * __tipc_node_link_down - handle loss of link
983  * @n: target tipc_node
984  * @bearer_id: id of the bearer
985  * @xmitq: queue for messages to be xmited on
986  * @maddr: output media address of the bearer
987  */
988 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
989 				  struct sk_buff_head *xmitq,
990 				  struct tipc_media_addr **maddr)
991 {
992 	struct tipc_link_entry *le = &n->links[*bearer_id];
993 	int *slot0 = &n->active_links[0];
994 	int *slot1 = &n->active_links[1];
995 	int i, highest = 0, prio;
996 	struct tipc_link *l, *_l, *tnl;
997 
998 	l = n->links[*bearer_id].link;
999 	if (!l || tipc_link_is_reset(l))
1000 		return;
1001 
1002 	n->working_links--;
1003 	n->action_flags |= TIPC_NOTIFY_LINK_DOWN;
1004 	n->link_id = tipc_link_id(l);
1005 
1006 	tipc_bearer_remove_dest(n->net, *bearer_id, n->addr);
1007 
1008 	pr_debug("Lost link <%s> on network plane %c\n",
1009 		 tipc_link_name(l), tipc_link_plane(l));
1010 
1011 	/* Select new active link if any available */
1012 	*slot0 = INVALID_BEARER_ID;
1013 	*slot1 = INVALID_BEARER_ID;
1014 	for (i = 0; i < MAX_BEARERS; i++) {
1015 		_l = n->links[i].link;
1016 		if (!_l || !tipc_link_is_up(_l))
1017 			continue;
1018 		if (_l == l)
1019 			continue;
1020 		prio = tipc_link_prio(_l);
1021 		if (prio < highest)
1022 			continue;
1023 		if (prio > highest) {
1024 			highest = prio;
1025 			*slot0 = i;
1026 			*slot1 = i;
1027 			continue;
1028 		}
1029 		*slot1 = i;
1030 	}
1031 
1032 	if (!node_is_up(n)) {
1033 		if (tipc_link_peer_is_down(l))
1034 			tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
1035 		tipc_node_fsm_evt(n, SELF_LOST_CONTACT_EVT);
1036 		trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down!");
1037 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1038 		tipc_link_reset(l);
1039 		tipc_link_build_reset_msg(l, xmitq);
1040 		*maddr = &n->links[*bearer_id].maddr;
1041 		node_lost_contact(n, &le->inputq);
1042 		tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
1043 		return;
1044 	}
1045 	tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
1046 
1047 	/* There is still a working link => initiate failover */
1048 	*bearer_id = n->active_links[0];
1049 	tnl = n->links[*bearer_id].link;
1050 	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
1051 	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
1052 	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
1053 	tipc_link_tnl_prepare(l, tnl, FAILOVER_MSG, xmitq);
1054 	trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down -> failover!");
1055 	tipc_link_reset(l);
1056 	tipc_link_fsm_evt(l, LINK_RESET_EVT);
1057 	tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
1058 	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
1059 	*maddr = &n->links[*bearer_id].maddr;
1060 }
1061 
1062 static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete)
1063 {
1064 	struct tipc_media_addr *maddr = NULL;
1065 	int old_bearer_id = bearer_id;
1066 	struct tipc_link_entry *le;
1067 	struct sk_buff_head xmitq;
1068 	struct tipc_link *l;
1069 
1070 	__skb_queue_head_init(&xmitq);
1071 
1072 	/* Synchronize the link lookup with bearer teardown. */
1073 	tipc_node_write_lock(n);
1074 	le = &n->links[bearer_id];
1075 	l = le->link;
1076 	if (!l) {
1077 		tipc_node_write_unlock_fast(n);
1078 		return;
1079 	}
1080 
1081 	if (!tipc_link_is_establishing(l)) {
1082 		__tipc_node_link_down(n, &bearer_id, &xmitq, &maddr);
1083 	} else {
1084 		/* Defuse pending tipc_node_link_up() */
1085 		tipc_link_reset(l);
1086 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1087 	}
1088 	if (delete) {
1089 		kfree(l);
1090 		le->link = NULL;
1091 		n->link_cnt--;
1092 	}
1093 	trace_tipc_node_link_down(n, true, "node link down or deleted!");
1094 	tipc_node_write_unlock(n);
1095 	if (delete)
1096 		tipc_mon_remove_peer(n->net, n->addr, old_bearer_id);
1097 	if (!skb_queue_empty(&xmitq))
1098 		tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr, n);
1099 	tipc_sk_rcv(n->net, &le->inputq);
1100 }
1101 
1102 static bool node_is_up(struct tipc_node *n)
1103 {
1104 	return n->active_links[0] != INVALID_BEARER_ID;
1105 }
1106 
1107 bool tipc_node_is_up(struct net *net, u32 addr)
1108 {
1109 	struct tipc_node *n;
1110 	bool retval = false;
1111 
1112 	if (in_own_node(net, addr))
1113 		return true;
1114 
1115 	n = tipc_node_find(net, addr);
1116 	if (!n)
1117 		return false;
1118 	retval = node_is_up(n);
1119 	tipc_node_put(n);
1120 	return retval;
1121 }
1122 
1123 static u32 tipc_node_suggest_addr(struct net *net, u32 addr)
1124 {
1125 	struct tipc_node *n;
1126 
1127 	addr ^= tipc_net(net)->random;
1128 	while ((n = tipc_node_find(net, addr))) {
1129 		tipc_node_put(n);
1130 		addr++;
1131 	}
1132 	return addr;
1133 }
1134 
1135 /* tipc_node_try_addr(): Check if addr can be used by peer, suggest other if not
1136  * Returns suggested address if any, otherwise 0
1137  */
1138 u32 tipc_node_try_addr(struct net *net, u8 *id, u32 addr)
1139 {
1140 	struct tipc_net *tn = tipc_net(net);
1141 	struct tipc_node *n;
1142 	bool preliminary;
1143 	u32 sugg_addr;
1144 
1145 	/* Suggest new address if some other peer is using this one */
1146 	n = tipc_node_find(net, addr);
1147 	if (n) {
1148 		if (!memcmp(n->peer_id, id, NODE_ID_LEN))
1149 			addr = 0;
1150 		tipc_node_put(n);
1151 		if (!addr)
1152 			return 0;
1153 		return tipc_node_suggest_addr(net, addr);
1154 	}
1155 
1156 	/* Suggest previously used address if peer is known */
1157 	n = tipc_node_find_by_id(net, id);
1158 	if (n) {
1159 		sugg_addr = n->addr;
1160 		preliminary = n->preliminary;
1161 		tipc_node_put(n);
1162 		if (!preliminary)
1163 			return sugg_addr;
1164 	}
1165 
1166 	/* Even this node may be in conflict */
1167 	if (tn->trial_addr == addr)
1168 		return tipc_node_suggest_addr(net, addr);
1169 
1170 	return 0;
1171 }
1172 
1173 void tipc_node_check_dest(struct net *net, u32 addr,
1174 			  u8 *peer_id, struct tipc_bearer *b,
1175 			  u16 capabilities, u32 signature, u32 hash_mixes,
1176 			  struct tipc_media_addr *maddr,
1177 			  bool *respond, bool *dupl_addr)
1178 {
1179 	struct tipc_node *n;
1180 	struct tipc_link *l;
1181 	struct tipc_link_entry *le;
1182 	bool addr_match = false;
1183 	bool sign_match = false;
1184 	bool link_up = false;
1185 	bool link_is_reset = false;
1186 	bool accept_addr = false;
1187 	bool reset = false;
1188 	char *if_name;
1189 	unsigned long intv;
1190 	u16 session;
1191 
1192 	*dupl_addr = false;
1193 	*respond = false;
1194 
1195 	n = tipc_node_create(net, addr, peer_id, capabilities, hash_mixes,
1196 			     false);
1197 	if (!n)
1198 		return;
1199 
1200 	tipc_node_write_lock(n);
1201 
1202 	le = &n->links[b->identity];
1203 
1204 	/* Prepare to validate requesting node's signature and media address */
1205 	l = le->link;
1206 	link_up = l && tipc_link_is_up(l);
1207 	link_is_reset = l && tipc_link_is_reset(l);
1208 	addr_match = l && !memcmp(&le->maddr, maddr, sizeof(*maddr));
1209 	sign_match = (signature == n->signature);
1210 
1211 	/* These three flags give us eight permutations: */
1212 
1213 	if (sign_match && addr_match && link_up) {
1214 		/* All is fine. Ignore requests. */
1215 		/* Peer node is not a container/local namespace */
1216 		if (!n->peer_hash_mix)
1217 			n->peer_hash_mix = hash_mixes;
1218 	} else if (sign_match && addr_match && !link_up) {
1219 		/* Respond. The link will come up in due time */
1220 		*respond = true;
1221 	} else if (sign_match && !addr_match && link_up) {
1222 		/* Peer has changed i/f address without rebooting.
1223 		 * If so, the link will reset soon, and the next
1224 		 * discovery will be accepted. So we can ignore it.
1225 		 * It may also be a cloned or malicious peer having
1226 		 * chosen the same node address and signature as an
1227 		 * existing one.
1228 		 * Ignore requests until the link goes down, if ever.
1229 		 */
1230 		*dupl_addr = true;
1231 	} else if (sign_match && !addr_match && !link_up) {
1232 		/* Peer link has changed i/f address without rebooting.
1233 		 * It may also be a cloned or malicious peer; we can't
1234 		 * distinguish between the two.
1235 		 * The signature is correct, so we must accept.
1236 		 */
1237 		accept_addr = true;
1238 		*respond = true;
1239 		reset = true;
1240 	} else if (!sign_match && addr_match && link_up) {
1241 		/* Peer node rebooted. Two possibilities:
1242 		 *  - Delayed re-discovery; this link endpoint has already
1243 		 *    reset and re-established contact with the peer, before
1244 		 *    receiving a discovery message from that node.
1245 		 *    (The peer happened to receive one from this node first).
1246 		 *  - The peer came back so fast that our side has not
1247 		 *    discovered it yet. Probing from this side will soon
1248 		 *    reset the link, since there can be no working link
1249 		 *    endpoint at the peer end, and the link will re-establish.
1250 		 *  Accept the signature, since it comes from a known peer.
1251 		 */
1252 		n->signature = signature;
1253 	} else if (!sign_match && addr_match && !link_up) {
1254 		/*  The peer node has rebooted.
1255 		 *  Accept signature, since it is a known peer.
1256 		 */
1257 		n->signature = signature;
1258 		*respond = true;
1259 	} else if (!sign_match && !addr_match && link_up) {
1260 		/* Peer rebooted with new address, or a new/duplicate peer.
1261 		 * Ignore until the link goes down, if ever.
1262 		 */
1263 		*dupl_addr = true;
1264 	} else if (!sign_match && !addr_match && !link_up) {
1265 		/* Peer rebooted with new address, or it is a new peer.
1266 		 * Accept signature and address.
1267 		 */
1268 		n->signature = signature;
1269 		accept_addr = true;
1270 		*respond = true;
1271 		reset = true;
1272 	}
1273 
1274 	if (!accept_addr)
1275 		goto exit;
1276 
1277 	/* Now create new link if not already existing */
1278 	if (!l) {
1279 		if (n->link_cnt == 2)
1280 			goto exit;
1281 
1282 		if_name = strchr(b->name, ':') + 1;
1283 		session = get_random_u16();
1284 		if (!tipc_link_create(net, if_name, b->identity, b->tolerance,
1285 				      b->net_plane, b->mtu, b->priority,
1286 				      b->min_win, b->max_win, session,
1287 				      tipc_own_addr(net), addr, peer_id,
1288 				      n->capabilities,
1289 				      tipc_bc_sndlink(n->net), n->bc_entry.link,
1290 				      &le->inputq,
1291 				      &n->bc_entry.namedq, &l)) {
1292 			*respond = false;
1293 			goto exit;
1294 		}
1295 		trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link created!");
1296 		tipc_link_reset(l);
1297 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1298 		if (n->state == NODE_FAILINGOVER)
1299 			tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
1300 		link_is_reset = tipc_link_is_reset(l);
1301 		le->link = l;
1302 		n->link_cnt++;
1303 		tipc_node_calculate_timer(n, l);
1304 		if (n->link_cnt == 1) {
1305 			intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
1306 			if (!mod_timer(&n->timer, intv))
1307 				tipc_node_get(n);
1308 		}
1309 	}
1310 	memcpy(&le->maddr, maddr, sizeof(*maddr));
1311 exit:
1312 	tipc_node_write_unlock(n);
1313 	if (reset && !link_is_reset)
1314 		tipc_node_link_down(n, b->identity, false);
1315 	tipc_node_put(n);
1316 }
1317 
1318 void tipc_node_delete_links(struct net *net, int bearer_id)
1319 {
1320 	struct tipc_net *tn = net_generic(net, tipc_net_id);
1321 	struct tipc_node *n;
1322 
1323 	rcu_read_lock();
1324 	list_for_each_entry_rcu(n, &tn->node_list, list) {
1325 		tipc_node_link_down(n, bearer_id, true);
1326 	}
1327 	rcu_read_unlock();
1328 }
1329 
1330 static void tipc_node_reset_links(struct tipc_node *n)
1331 {
1332 	int i;
1333 
1334 	pr_warn("Resetting all links to %x\n", n->addr);
1335 
1336 	tipc_node_write_lock(n);
1337 	trace_tipc_node_reset_links(n, true, " ");
1338 	tipc_node_write_unlock_fast(n);
1339 	for (i = 0; i < MAX_BEARERS; i++) {
1340 		tipc_node_link_down(n, i, false);
1341 	}
1342 }
1343 
1344 /* tipc_node_fsm_evt - node finite state machine
1345  * Determines when contact is allowed with peer node
1346  */
1347 static void tipc_node_fsm_evt(struct tipc_node *n, int evt)
1348 {
1349 	int state = n->state;
1350 
1351 	switch (state) {
1352 	case SELF_DOWN_PEER_DOWN:
1353 		switch (evt) {
1354 		case SELF_ESTABL_CONTACT_EVT:
1355 			state = SELF_UP_PEER_COMING;
1356 			break;
1357 		case PEER_ESTABL_CONTACT_EVT:
1358 			state = SELF_COMING_PEER_UP;
1359 			break;
1360 		case SELF_LOST_CONTACT_EVT:
1361 		case PEER_LOST_CONTACT_EVT:
1362 			break;
1363 		case NODE_SYNCH_END_EVT:
1364 		case NODE_SYNCH_BEGIN_EVT:
1365 		case NODE_FAILOVER_BEGIN_EVT:
1366 		case NODE_FAILOVER_END_EVT:
1367 		default:
1368 			goto illegal_evt;
1369 		}
1370 		break;
1371 	case SELF_UP_PEER_UP:
1372 		switch (evt) {
1373 		case SELF_LOST_CONTACT_EVT:
1374 			state = SELF_DOWN_PEER_LEAVING;
1375 			break;
1376 		case PEER_LOST_CONTACT_EVT:
1377 			state = SELF_LEAVING_PEER_DOWN;
1378 			break;
1379 		case NODE_SYNCH_BEGIN_EVT:
1380 			state = NODE_SYNCHING;
1381 			break;
1382 		case NODE_FAILOVER_BEGIN_EVT:
1383 			state = NODE_FAILINGOVER;
1384 			break;
1385 		case SELF_ESTABL_CONTACT_EVT:
1386 		case PEER_ESTABL_CONTACT_EVT:
1387 		case NODE_SYNCH_END_EVT:
1388 		case NODE_FAILOVER_END_EVT:
1389 			break;
1390 		default:
1391 			goto illegal_evt;
1392 		}
1393 		break;
1394 	case SELF_DOWN_PEER_LEAVING:
1395 		switch (evt) {
1396 		case PEER_LOST_CONTACT_EVT:
1397 			state = SELF_DOWN_PEER_DOWN;
1398 			break;
1399 		case SELF_ESTABL_CONTACT_EVT:
1400 		case PEER_ESTABL_CONTACT_EVT:
1401 		case SELF_LOST_CONTACT_EVT:
1402 			break;
1403 		case NODE_SYNCH_END_EVT:
1404 		case NODE_SYNCH_BEGIN_EVT:
1405 		case NODE_FAILOVER_BEGIN_EVT:
1406 		case NODE_FAILOVER_END_EVT:
1407 		default:
1408 			goto illegal_evt;
1409 		}
1410 		break;
1411 	case SELF_UP_PEER_COMING:
1412 		switch (evt) {
1413 		case PEER_ESTABL_CONTACT_EVT:
1414 			state = SELF_UP_PEER_UP;
1415 			break;
1416 		case SELF_LOST_CONTACT_EVT:
1417 			state = SELF_DOWN_PEER_DOWN;
1418 			break;
1419 		case SELF_ESTABL_CONTACT_EVT:
1420 		case PEER_LOST_CONTACT_EVT:
1421 		case NODE_SYNCH_END_EVT:
1422 		case NODE_FAILOVER_BEGIN_EVT:
1423 			break;
1424 		case NODE_SYNCH_BEGIN_EVT:
1425 		case NODE_FAILOVER_END_EVT:
1426 		default:
1427 			goto illegal_evt;
1428 		}
1429 		break;
1430 	case SELF_COMING_PEER_UP:
1431 		switch (evt) {
1432 		case SELF_ESTABL_CONTACT_EVT:
1433 			state = SELF_UP_PEER_UP;
1434 			break;
1435 		case PEER_LOST_CONTACT_EVT:
1436 			state = SELF_DOWN_PEER_DOWN;
1437 			break;
1438 		case SELF_LOST_CONTACT_EVT:
1439 		case PEER_ESTABL_CONTACT_EVT:
1440 			break;
1441 		case NODE_SYNCH_END_EVT:
1442 		case NODE_SYNCH_BEGIN_EVT:
1443 		case NODE_FAILOVER_BEGIN_EVT:
1444 		case NODE_FAILOVER_END_EVT:
1445 		default:
1446 			goto illegal_evt;
1447 		}
1448 		break;
1449 	case SELF_LEAVING_PEER_DOWN:
1450 		switch (evt) {
1451 		case SELF_LOST_CONTACT_EVT:
1452 			state = SELF_DOWN_PEER_DOWN;
1453 			break;
1454 		case SELF_ESTABL_CONTACT_EVT:
1455 		case PEER_ESTABL_CONTACT_EVT:
1456 		case PEER_LOST_CONTACT_EVT:
1457 			break;
1458 		case NODE_SYNCH_END_EVT:
1459 		case NODE_SYNCH_BEGIN_EVT:
1460 		case NODE_FAILOVER_BEGIN_EVT:
1461 		case NODE_FAILOVER_END_EVT:
1462 		default:
1463 			goto illegal_evt;
1464 		}
1465 		break;
1466 	case NODE_FAILINGOVER:
1467 		switch (evt) {
1468 		case SELF_LOST_CONTACT_EVT:
1469 			state = SELF_DOWN_PEER_LEAVING;
1470 			break;
1471 		case PEER_LOST_CONTACT_EVT:
1472 			state = SELF_LEAVING_PEER_DOWN;
1473 			break;
1474 		case NODE_FAILOVER_END_EVT:
1475 			state = SELF_UP_PEER_UP;
1476 			break;
1477 		case NODE_FAILOVER_BEGIN_EVT:
1478 		case SELF_ESTABL_CONTACT_EVT:
1479 		case PEER_ESTABL_CONTACT_EVT:
1480 			break;
1481 		case NODE_SYNCH_BEGIN_EVT:
1482 		case NODE_SYNCH_END_EVT:
1483 		default:
1484 			goto illegal_evt;
1485 		}
1486 		break;
1487 	case NODE_SYNCHING:
1488 		switch (evt) {
1489 		case SELF_LOST_CONTACT_EVT:
1490 			state = SELF_DOWN_PEER_LEAVING;
1491 			break;
1492 		case PEER_LOST_CONTACT_EVT:
1493 			state = SELF_LEAVING_PEER_DOWN;
1494 			break;
1495 		case NODE_SYNCH_END_EVT:
1496 			state = SELF_UP_PEER_UP;
1497 			break;
1498 		case NODE_FAILOVER_BEGIN_EVT:
1499 			state = NODE_FAILINGOVER;
1500 			break;
1501 		case NODE_SYNCH_BEGIN_EVT:
1502 		case SELF_ESTABL_CONTACT_EVT:
1503 		case PEER_ESTABL_CONTACT_EVT:
1504 			break;
1505 		case NODE_FAILOVER_END_EVT:
1506 		default:
1507 			goto illegal_evt;
1508 		}
1509 		break;
1510 	default:
1511 		pr_err("Unknown node fsm state %x\n", state);
1512 		break;
1513 	}
1514 	trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
1515 	n->state = state;
1516 	return;
1517 
1518 illegal_evt:
1519 	pr_err("Illegal node fsm evt %x in state %x\n", evt, state);
1520 	trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
1521 }
1522 
1523 static void node_lost_contact(struct tipc_node *n,
1524 			      struct sk_buff_head *inputq)
1525 {
1526 	struct tipc_sock_conn *conn, *safe;
1527 	struct tipc_link *l;
1528 	struct list_head *conns = &n->conn_sks;
1529 	struct sk_buff *skb;
1530 	uint i;
1531 
1532 	pr_debug("Lost contact with %x\n", n->addr);
1533 	n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
1534 	trace_tipc_node_lost_contact(n, true, " ");
1535 
1536 	/* Clean up broadcast state */
1537 	tipc_bcast_remove_peer(n->net, n->bc_entry.link);
1538 	skb_queue_purge(&n->bc_entry.namedq);
1539 
1540 	/* Abort any ongoing link failover */
1541 	for (i = 0; i < MAX_BEARERS; i++) {
1542 		l = n->links[i].link;
1543 		if (l)
1544 			tipc_link_fsm_evt(l, LINK_FAILOVER_END_EVT);
1545 	}
1546 
1547 	/* Notify publications from this node */
1548 	n->action_flags |= TIPC_NOTIFY_NODE_DOWN;
1549 	n->peer_net = NULL;
1550 	n->peer_hash_mix = 0;
1551 	/* Notify sockets connected to node */
1552 	list_for_each_entry_safe(conn, safe, conns, list) {
1553 		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_CONN_MSG,
1554 				      SHORT_H_SIZE, 0, tipc_own_addr(n->net),
1555 				      conn->peer_node, conn->port,
1556 				      conn->peer_port, TIPC_ERR_NO_NODE);
1557 		if (likely(skb))
1558 			skb_queue_tail(inputq, skb);
1559 		list_del(&conn->list);
1560 		kfree(conn);
1561 	}
1562 }
1563 
1564 /**
1565  * tipc_node_get_linkname - get the name of a link
1566  *
1567  * @net: the applicable net namespace
1568  * @bearer_id: id of the bearer
1569  * @addr: peer node address
1570  * @linkname: link name output buffer
1571  * @len: size of @linkname output buffer
1572  *
1573  * Return: 0 on success
1574  */
1575 int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 addr,
1576 			   char *linkname, size_t len)
1577 {
1578 	struct tipc_link *link;
1579 	int err = -EINVAL;
1580 	struct tipc_node *node = tipc_node_find(net, addr);
1581 
1582 	if (!node)
1583 		return err;
1584 
1585 	if (bearer_id >= MAX_BEARERS)
1586 		goto exit;
1587 
1588 	tipc_node_read_lock(node);
1589 	link = node->links[bearer_id].link;
1590 	if (link) {
1591 		strscpy(linkname, tipc_link_name(link), len);
1592 		err = 0;
1593 	}
1594 	tipc_node_read_unlock(node);
1595 exit:
1596 	tipc_node_put(node);
1597 	return err;
1598 }
1599 
1600 /* Caller should hold node lock for the passed node */
1601 static int __tipc_nl_add_node(struct tipc_nl_msg *msg, struct tipc_node *node)
1602 {
1603 	void *hdr;
1604 	struct nlattr *attrs;
1605 
1606 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1607 			  NLM_F_MULTI, TIPC_NL_NODE_GET);
1608 	if (!hdr)
1609 		return -EMSGSIZE;
1610 
1611 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NODE);
1612 	if (!attrs)
1613 		goto msg_full;
1614 
1615 	if (nla_put_u32(msg->skb, TIPC_NLA_NODE_ADDR, node->addr))
1616 		goto attr_msg_full;
1617 	if (node_is_up(node))
1618 		if (nla_put_flag(msg->skb, TIPC_NLA_NODE_UP))
1619 			goto attr_msg_full;
1620 
1621 	nla_nest_end(msg->skb, attrs);
1622 	genlmsg_end(msg->skb, hdr);
1623 
1624 	return 0;
1625 
1626 attr_msg_full:
1627 	nla_nest_cancel(msg->skb, attrs);
1628 msg_full:
1629 	genlmsg_cancel(msg->skb, hdr);
1630 
1631 	return -EMSGSIZE;
1632 }
1633 
1634 static void tipc_lxc_xmit(struct net *peer_net, struct sk_buff_head *list)
1635 {
1636 	struct tipc_msg *hdr = buf_msg(skb_peek(list));
1637 	struct sk_buff_head inputq;
1638 
1639 	switch (msg_user(hdr)) {
1640 	case TIPC_LOW_IMPORTANCE:
1641 	case TIPC_MEDIUM_IMPORTANCE:
1642 	case TIPC_HIGH_IMPORTANCE:
1643 	case TIPC_CRITICAL_IMPORTANCE:
1644 		if (msg_connected(hdr) || msg_named(hdr) ||
1645 		    msg_direct(hdr)) {
1646 			tipc_loopback_trace(peer_net, list);
1647 			spin_lock_init(&list->lock);
1648 			tipc_sk_rcv(peer_net, list);
1649 			return;
1650 		}
1651 		if (msg_mcast(hdr)) {
1652 			tipc_loopback_trace(peer_net, list);
1653 			skb_queue_head_init(&inputq);
1654 			tipc_sk_mcast_rcv(peer_net, list, &inputq);
1655 			__skb_queue_purge(list);
1656 			skb_queue_purge(&inputq);
1657 			return;
1658 		}
1659 		return;
1660 	case MSG_FRAGMENTER:
1661 		if (tipc_msg_assemble(list)) {
1662 			tipc_loopback_trace(peer_net, list);
1663 			skb_queue_head_init(&inputq);
1664 			tipc_sk_mcast_rcv(peer_net, list, &inputq);
1665 			__skb_queue_purge(list);
1666 			skb_queue_purge(&inputq);
1667 		}
1668 		return;
1669 	case GROUP_PROTOCOL:
1670 	case CONN_MANAGER:
1671 		tipc_loopback_trace(peer_net, list);
1672 		spin_lock_init(&list->lock);
1673 		tipc_sk_rcv(peer_net, list);
1674 		return;
1675 	case LINK_PROTOCOL:
1676 	case NAME_DISTRIBUTOR:
1677 	case TUNNEL_PROTOCOL:
1678 	case BCAST_PROTOCOL:
1679 		return;
1680 	default:
1681 		return;
1682 	}
1683 }
1684 
1685 /**
1686  * tipc_node_xmit() - general link level function for message sending
1687  * @net: the applicable net namespace
1688  * @list: chain of buffers containing message
1689  * @dnode: address of destination node
1690  * @selector: a number used for deterministic link selection
1691  * Consumes the buffer chain.
1692  * Return: 0 if success, otherwise: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE,-ENOBUF
1693  */
1694 int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
1695 		   u32 dnode, int selector)
1696 {
1697 	struct tipc_link_entry *le = NULL;
1698 	struct tipc_node *n;
1699 	struct sk_buff_head xmitq;
1700 	bool node_up = false;
1701 	struct net *peer_net;
1702 	int bearer_id;
1703 	int rc;
1704 
1705 	if (in_own_node(net, dnode)) {
1706 		tipc_loopback_trace(net, list);
1707 		spin_lock_init(&list->lock);
1708 		tipc_sk_rcv(net, list);
1709 		return 0;
1710 	}
1711 
1712 	n = tipc_node_find(net, dnode);
1713 	if (unlikely(!n)) {
1714 		__skb_queue_purge(list);
1715 		return -EHOSTUNREACH;
1716 	}
1717 
1718 	rcu_read_lock();
1719 	tipc_node_read_lock(n);
1720 	node_up = node_is_up(n);
1721 	peer_net = n->peer_net;
1722 	tipc_node_read_unlock(n);
1723 	if (node_up && peer_net && check_net(peer_net)) {
1724 		/* xmit inner linux container */
1725 		tipc_lxc_xmit(peer_net, list);
1726 		if (likely(skb_queue_empty(list))) {
1727 			rcu_read_unlock();
1728 			tipc_node_put(n);
1729 			return 0;
1730 		}
1731 	}
1732 	rcu_read_unlock();
1733 
1734 	tipc_node_read_lock(n);
1735 	bearer_id = n->active_links[selector & 1];
1736 	if (unlikely(bearer_id == INVALID_BEARER_ID)) {
1737 		tipc_node_read_unlock(n);
1738 		tipc_node_put(n);
1739 		__skb_queue_purge(list);
1740 		return -EHOSTUNREACH;
1741 	}
1742 
1743 	__skb_queue_head_init(&xmitq);
1744 	le = &n->links[bearer_id];
1745 	spin_lock_bh(&le->lock);
1746 	rc = tipc_link_xmit(le->link, list, &xmitq);
1747 	spin_unlock_bh(&le->lock);
1748 	tipc_node_read_unlock(n);
1749 
1750 	if (unlikely(rc == -ENOBUFS))
1751 		tipc_node_link_down(n, bearer_id, false);
1752 	else
1753 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
1754 
1755 	tipc_node_put(n);
1756 
1757 	return rc;
1758 }
1759 
1760 /* tipc_node_xmit_skb(): send single buffer to destination
1761  * Buffers sent via this function are generally TIPC_SYSTEM_IMPORTANCE
1762  * messages, which will not be rejected
1763  * The only exception is datagram messages rerouted after secondary
1764  * lookup, which are rare and safe to dispose of anyway.
1765  */
1766 int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode,
1767 		       u32 selector)
1768 {
1769 	struct sk_buff_head head;
1770 
1771 	__skb_queue_head_init(&head);
1772 	__skb_queue_tail(&head, skb);
1773 	tipc_node_xmit(net, &head, dnode, selector);
1774 	return 0;
1775 }
1776 
1777 /* tipc_node_distr_xmit(): send single buffer msgs to individual destinations
1778  * Note: this is only for SYSTEM_IMPORTANCE messages, which cannot be rejected
1779  */
1780 int tipc_node_distr_xmit(struct net *net, struct sk_buff_head *xmitq)
1781 {
1782 	struct sk_buff *skb;
1783 	u32 selector, dnode;
1784 
1785 	while ((skb = __skb_dequeue(xmitq))) {
1786 		selector = msg_origport(buf_msg(skb));
1787 		dnode = msg_destnode(buf_msg(skb));
1788 		tipc_node_xmit_skb(net, skb, dnode, selector);
1789 	}
1790 	return 0;
1791 }
1792 
1793 void tipc_node_broadcast(struct net *net, struct sk_buff *skb, int rc_dests)
1794 {
1795 	struct sk_buff_head xmitq;
1796 	struct sk_buff *txskb;
1797 	struct tipc_node *n;
1798 	u16 dummy;
1799 	u32 dst;
1800 
1801 	/* Use broadcast if all nodes support it */
1802 	if (!rc_dests && tipc_bcast_get_mode(net) != BCLINK_MODE_RCAST) {
1803 		__skb_queue_head_init(&xmitq);
1804 		__skb_queue_tail(&xmitq, skb);
1805 		tipc_bcast_xmit(net, &xmitq, &dummy);
1806 		return;
1807 	}
1808 
1809 	/* Otherwise use legacy replicast method */
1810 	rcu_read_lock();
1811 	list_for_each_entry_rcu(n, tipc_nodes(net), list) {
1812 		dst = n->addr;
1813 		if (in_own_node(net, dst))
1814 			continue;
1815 		if (!node_is_up(n))
1816 			continue;
1817 		txskb = pskb_copy(skb, GFP_ATOMIC);
1818 		if (!txskb)
1819 			break;
1820 		msg_set_destnode(buf_msg(txskb), dst);
1821 		tipc_node_xmit_skb(net, txskb, dst, 0);
1822 	}
1823 	rcu_read_unlock();
1824 	kfree_skb(skb);
1825 }
1826 
1827 static void tipc_node_mcast_rcv(struct tipc_node *n)
1828 {
1829 	struct tipc_bclink_entry *be = &n->bc_entry;
1830 
1831 	/* 'arrvq' is under inputq2's lock protection */
1832 	spin_lock_bh(&be->inputq2.lock);
1833 	spin_lock_bh(&be->inputq1.lock);
1834 	skb_queue_splice_tail_init(&be->inputq1, &be->arrvq);
1835 	spin_unlock_bh(&be->inputq1.lock);
1836 	spin_unlock_bh(&be->inputq2.lock);
1837 	tipc_sk_mcast_rcv(n->net, &be->arrvq, &be->inputq2);
1838 }
1839 
1840 static void tipc_node_bc_sync_rcv(struct tipc_node *n, struct tipc_msg *hdr,
1841 				  int bearer_id, struct sk_buff_head *xmitq,
1842 				  bool *valid)
1843 {
1844 	struct tipc_link *ucl;
1845 	int rc;
1846 
1847 	rc = tipc_bcast_sync_rcv(n->net, n->bc_entry.link, hdr, xmitq, valid);
1848 	if (!*valid)
1849 		return;
1850 
1851 	if (rc & TIPC_LINK_DOWN_EVT) {
1852 		tipc_node_reset_links(n);
1853 		return;
1854 	}
1855 
1856 	if (!(rc & TIPC_LINK_SND_STATE))
1857 		return;
1858 
1859 	/* If probe message, a STATE response will be sent anyway */
1860 	if (msg_probe(hdr))
1861 		return;
1862 
1863 	/* Produce a STATE message carrying broadcast NACK */
1864 	tipc_node_read_lock(n);
1865 	ucl = n->links[bearer_id].link;
1866 	if (ucl)
1867 		tipc_link_build_state_msg(ucl, xmitq);
1868 	tipc_node_read_unlock(n);
1869 }
1870 
1871 /**
1872  * tipc_node_bc_rcv - process TIPC broadcast packet arriving from off-node
1873  * @net: the applicable net namespace
1874  * @skb: TIPC packet
1875  * @bearer_id: id of bearer message arrived on
1876  *
1877  * Invoked with no locks held.
1878  */
1879 static void tipc_node_bc_rcv(struct net *net, struct sk_buff *skb, int bearer_id)
1880 {
1881 	int rc;
1882 	struct sk_buff_head xmitq;
1883 	struct tipc_bclink_entry *be;
1884 	struct tipc_link_entry *le;
1885 	struct tipc_msg *hdr = buf_msg(skb);
1886 	int usr = msg_user(hdr);
1887 	u32 dnode = msg_destnode(hdr);
1888 	struct tipc_node *n;
1889 
1890 	__skb_queue_head_init(&xmitq);
1891 
1892 	/* If NACK for other node, let rcv link for that node peek into it */
1893 	if ((usr == BCAST_PROTOCOL) && (dnode != tipc_own_addr(net)))
1894 		n = tipc_node_find(net, dnode);
1895 	else
1896 		n = tipc_node_find(net, msg_prevnode(hdr));
1897 	if (!n) {
1898 		kfree_skb(skb);
1899 		return;
1900 	}
1901 	be = &n->bc_entry;
1902 	le = &n->links[bearer_id];
1903 
1904 	rc = tipc_bcast_rcv(net, be->link, skb);
1905 
1906 	/* Broadcast ACKs are sent on a unicast link */
1907 	if (rc & TIPC_LINK_SND_STATE) {
1908 		tipc_node_read_lock(n);
1909 		tipc_link_build_state_msg(le->link, &xmitq);
1910 		tipc_node_read_unlock(n);
1911 	}
1912 
1913 	if (!skb_queue_empty(&xmitq))
1914 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
1915 
1916 	if (!skb_queue_empty(&be->inputq1))
1917 		tipc_node_mcast_rcv(n);
1918 
1919 	/* Handle NAME_DISTRIBUTOR messages sent from 1.7 nodes */
1920 	if (!skb_queue_empty(&n->bc_entry.namedq))
1921 		tipc_named_rcv(net, &n->bc_entry.namedq,
1922 			       &n->bc_entry.named_rcv_nxt,
1923 			       &n->bc_entry.named_open);
1924 
1925 	/* If reassembly or retransmission failure => reset all links to peer */
1926 	if (rc & TIPC_LINK_DOWN_EVT)
1927 		tipc_node_reset_links(n);
1928 
1929 	tipc_node_put(n);
1930 }
1931 
1932 /**
1933  * tipc_node_check_state - check and if necessary update node state
1934  * @n: target tipc_node
1935  * @skb: TIPC packet
1936  * @bearer_id: identity of bearer delivering the packet
1937  * @xmitq: queue for messages to be xmited on
1938  * Return: true if state and msg are ok, otherwise false
1939  */
1940 static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
1941 				  int bearer_id, struct sk_buff_head *xmitq)
1942 {
1943 	struct tipc_msg *hdr = buf_msg(skb);
1944 	int usr = msg_user(hdr);
1945 	int mtyp = msg_type(hdr);
1946 	u16 oseqno = msg_seqno(hdr);
1947 	u16 exp_pkts = msg_msgcnt(hdr);
1948 	u16 rcv_nxt, syncpt, dlv_nxt, inputq_len;
1949 	int state = n->state;
1950 	struct tipc_link *l, *tnl, *pl = NULL;
1951 	struct tipc_media_addr *maddr;
1952 	int pb_id;
1953 
1954 	if (trace_tipc_node_check_state_enabled()) {
1955 		trace_tipc_skb_dump(skb, false, "skb for node state check");
1956 		trace_tipc_node_check_state(n, true, " ");
1957 	}
1958 	l = n->links[bearer_id].link;
1959 	if (!l)
1960 		return false;
1961 	rcv_nxt = tipc_link_rcv_nxt(l);
1962 
1963 
1964 	if (likely((state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL)))
1965 		return true;
1966 
1967 	/* Find parallel link, if any */
1968 	for (pb_id = 0; pb_id < MAX_BEARERS; pb_id++) {
1969 		if ((pb_id != bearer_id) && n->links[pb_id].link) {
1970 			pl = n->links[pb_id].link;
1971 			break;
1972 		}
1973 	}
1974 
1975 	if (!tipc_link_validate_msg(l, hdr)) {
1976 		trace_tipc_skb_dump(skb, false, "PROTO invalid (2)!");
1977 		trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (2)!");
1978 		return false;
1979 	}
1980 
1981 	/* Check and update node accesibility if applicable */
1982 	if (state == SELF_UP_PEER_COMING) {
1983 		if (!tipc_link_is_up(l))
1984 			return true;
1985 		if (!msg_peer_link_is_up(hdr))
1986 			return true;
1987 		tipc_node_fsm_evt(n, PEER_ESTABL_CONTACT_EVT);
1988 	}
1989 
1990 	if (state == SELF_DOWN_PEER_LEAVING) {
1991 		if (msg_peer_node_is_up(hdr))
1992 			return false;
1993 		tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
1994 		return true;
1995 	}
1996 
1997 	if (state == SELF_LEAVING_PEER_DOWN)
1998 		return false;
1999 
2000 	/* Ignore duplicate packets */
2001 	if ((usr != LINK_PROTOCOL) && less(oseqno, rcv_nxt))
2002 		return true;
2003 
2004 	/* Initiate or update failover mode if applicable */
2005 	if ((usr == TUNNEL_PROTOCOL) && (mtyp == FAILOVER_MSG)) {
2006 		syncpt = oseqno + exp_pkts - 1;
2007 		if (pl && !tipc_link_is_reset(pl)) {
2008 			__tipc_node_link_down(n, &pb_id, xmitq, &maddr);
2009 			trace_tipc_node_link_down(n, true,
2010 						  "node link down <- failover!");
2011 			tipc_skb_queue_splice_tail_init(tipc_link_inputq(pl),
2012 							tipc_link_inputq(l));
2013 		}
2014 
2015 		/* If parallel link was already down, and this happened before
2016 		 * the tunnel link came up, node failover was never started.
2017 		 * Ensure that a FAILOVER_MSG is sent to get peer out of
2018 		 * NODE_FAILINGOVER state, also this node must accept
2019 		 * TUNNEL_MSGs from peer.
2020 		 */
2021 		if (n->state != NODE_FAILINGOVER)
2022 			tipc_node_link_failover(n, pl, l, xmitq);
2023 
2024 		/* If pkts arrive out of order, use lowest calculated syncpt */
2025 		if (less(syncpt, n->sync_point))
2026 			n->sync_point = syncpt;
2027 	}
2028 
2029 	/* Open parallel link when tunnel link reaches synch point */
2030 	if ((n->state == NODE_FAILINGOVER) && tipc_link_is_up(l)) {
2031 		if (!more(rcv_nxt, n->sync_point))
2032 			return true;
2033 		tipc_node_fsm_evt(n, NODE_FAILOVER_END_EVT);
2034 		if (pl)
2035 			tipc_link_fsm_evt(pl, LINK_FAILOVER_END_EVT);
2036 		return true;
2037 	}
2038 
2039 	/* No syncing needed if only one link */
2040 	if (!pl || !tipc_link_is_up(pl))
2041 		return true;
2042 
2043 	/* Initiate synch mode if applicable */
2044 	if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG) && (oseqno == 1)) {
2045 		if (n->capabilities & TIPC_TUNNEL_ENHANCED)
2046 			syncpt = msg_syncpt(hdr);
2047 		else
2048 			syncpt = msg_seqno(msg_inner_hdr(hdr)) + exp_pkts - 1;
2049 		if (!tipc_link_is_up(l))
2050 			__tipc_node_link_up(n, bearer_id, xmitq);
2051 		if (n->state == SELF_UP_PEER_UP) {
2052 			n->sync_point = syncpt;
2053 			tipc_link_fsm_evt(l, LINK_SYNCH_BEGIN_EVT);
2054 			tipc_node_fsm_evt(n, NODE_SYNCH_BEGIN_EVT);
2055 		}
2056 	}
2057 
2058 	/* Open tunnel link when parallel link reaches synch point */
2059 	if (n->state == NODE_SYNCHING) {
2060 		if (tipc_link_is_synching(l)) {
2061 			tnl = l;
2062 		} else {
2063 			tnl = pl;
2064 			pl = l;
2065 		}
2066 		inputq_len = skb_queue_len(tipc_link_inputq(pl));
2067 		dlv_nxt = tipc_link_rcv_nxt(pl) - inputq_len;
2068 		if (more(dlv_nxt, n->sync_point)) {
2069 			tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
2070 			tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
2071 			return true;
2072 		}
2073 		if (l == pl)
2074 			return true;
2075 		if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG))
2076 			return true;
2077 		if (usr == LINK_PROTOCOL)
2078 			return true;
2079 		return false;
2080 	}
2081 	return true;
2082 }
2083 
2084 /**
2085  * tipc_rcv - process TIPC packets/messages arriving from off-node
2086  * @net: the applicable net namespace
2087  * @skb: TIPC packet
2088  * @b: pointer to bearer message arrived on
2089  *
2090  * Invoked with no locks held. Bearer pointer must point to a valid bearer
2091  * structure (i.e. cannot be NULL), but bearer can be inactive.
2092  */
2093 void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
2094 {
2095 	struct sk_buff_head xmitq;
2096 	struct tipc_link_entry *le;
2097 	struct tipc_msg *hdr;
2098 	struct tipc_node *n;
2099 	int bearer_id = b->identity;
2100 	u32 self = tipc_own_addr(net);
2101 	int usr, rc = 0;
2102 	u16 bc_ack;
2103 #ifdef CONFIG_TIPC_CRYPTO
2104 	struct tipc_ehdr *ehdr;
2105 
2106 	/* Check if message must be decrypted first */
2107 	if (TIPC_SKB_CB(skb)->decrypted || !tipc_ehdr_validate(skb))
2108 		goto rcv;
2109 
2110 	ehdr = (struct tipc_ehdr *)skb->data;
2111 	if (likely(ehdr->user != LINK_CONFIG)) {
2112 		n = tipc_node_find(net, ntohl(ehdr->addr));
2113 		if (unlikely(!n))
2114 			goto discard;
2115 	} else {
2116 		n = tipc_node_find_by_id(net, ehdr->id);
2117 	}
2118 	skb_dst_force(skb);
2119 	tipc_crypto_rcv(net, (n) ? n->crypto_rx : NULL, &skb, b);
2120 	if (!skb)
2121 		return;
2122 
2123 rcv:
2124 #endif
2125 	/* Ensure message is well-formed before touching the header */
2126 	if (unlikely(!tipc_msg_validate(&skb)))
2127 		goto discard;
2128 	__skb_queue_head_init(&xmitq);
2129 	hdr = buf_msg(skb);
2130 	usr = msg_user(hdr);
2131 	bc_ack = msg_bcast_ack(hdr);
2132 
2133 	/* Handle arrival of discovery or broadcast packet */
2134 	if (unlikely(msg_non_seq(hdr))) {
2135 		if (unlikely(usr == LINK_CONFIG))
2136 			return tipc_disc_rcv(net, skb, b);
2137 		else
2138 			return tipc_node_bc_rcv(net, skb, bearer_id);
2139 	}
2140 
2141 	/* Discard unicast link messages destined for another node */
2142 	if (unlikely(!msg_short(hdr) && (msg_destnode(hdr) != self)))
2143 		goto discard;
2144 
2145 	/* Locate neighboring node that sent packet */
2146 	n = tipc_node_find(net, msg_prevnode(hdr));
2147 	if (unlikely(!n))
2148 		goto discard;
2149 	le = &n->links[bearer_id];
2150 
2151 	/* Ensure broadcast reception is in synch with peer's send state */
2152 	if (unlikely(usr == LINK_PROTOCOL)) {
2153 		bool valid = true;
2154 
2155 		if (unlikely(skb_linearize(skb))) {
2156 			tipc_node_put(n);
2157 			goto discard;
2158 		}
2159 		hdr = buf_msg(skb);
2160 		tipc_node_bc_sync_rcv(n, hdr, bearer_id, &xmitq, &valid);
2161 		if (!valid) {
2162 			tipc_node_put(n);
2163 			goto discard;
2164 		}
2165 	} else if (unlikely(tipc_link_acked(n->bc_entry.link) != bc_ack)) {
2166 		tipc_bcast_ack_rcv(net, n->bc_entry.link, hdr);
2167 	}
2168 
2169 	/* Receive packet directly if conditions permit */
2170 	tipc_node_read_lock(n);
2171 	if (likely((n->state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL))) {
2172 		spin_lock_bh(&le->lock);
2173 		if (le->link) {
2174 			rc = tipc_link_rcv(le->link, skb, &xmitq);
2175 			skb = NULL;
2176 		}
2177 		spin_unlock_bh(&le->lock);
2178 	}
2179 	tipc_node_read_unlock(n);
2180 
2181 	/* Check/update node state before receiving */
2182 	if (unlikely(skb)) {
2183 		if (unlikely(skb_linearize(skb)))
2184 			goto out_node_put;
2185 		tipc_node_write_lock(n);
2186 		if (tipc_node_check_state(n, skb, bearer_id, &xmitq)) {
2187 			if (le->link) {
2188 				rc = tipc_link_rcv(le->link, skb, &xmitq);
2189 				skb = NULL;
2190 			}
2191 		}
2192 		tipc_node_write_unlock(n);
2193 	}
2194 
2195 	if (unlikely(rc & TIPC_LINK_UP_EVT))
2196 		tipc_node_link_up(n, bearer_id, &xmitq);
2197 
2198 	if (unlikely(rc & TIPC_LINK_DOWN_EVT))
2199 		tipc_node_link_down(n, bearer_id, false);
2200 
2201 	if (unlikely(!skb_queue_empty(&n->bc_entry.namedq)))
2202 		tipc_named_rcv(net, &n->bc_entry.namedq,
2203 			       &n->bc_entry.named_rcv_nxt,
2204 			       &n->bc_entry.named_open);
2205 
2206 	if (unlikely(!skb_queue_empty(&n->bc_entry.inputq1)))
2207 		tipc_node_mcast_rcv(n);
2208 
2209 	if (!skb_queue_empty(&le->inputq))
2210 		tipc_sk_rcv(net, &le->inputq);
2211 
2212 	if (!skb_queue_empty(&xmitq))
2213 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
2214 
2215 out_node_put:
2216 	tipc_node_put(n);
2217 discard:
2218 	kfree_skb(skb);
2219 }
2220 
2221 void tipc_node_apply_property(struct net *net, struct tipc_bearer *b,
2222 			      int prop)
2223 {
2224 	struct tipc_net *tn = tipc_net(net);
2225 	int bearer_id = b->identity;
2226 	struct sk_buff_head xmitq;
2227 	struct tipc_link_entry *e;
2228 	struct tipc_node *n;
2229 
2230 	__skb_queue_head_init(&xmitq);
2231 
2232 	rcu_read_lock();
2233 
2234 	list_for_each_entry_rcu(n, &tn->node_list, list) {
2235 		tipc_node_write_lock(n);
2236 		e = &n->links[bearer_id];
2237 		if (e->link) {
2238 			if (prop == TIPC_NLA_PROP_TOL)
2239 				tipc_link_set_tolerance(e->link, b->tolerance,
2240 							&xmitq);
2241 			else if (prop == TIPC_NLA_PROP_MTU)
2242 				tipc_link_set_mtu(e->link, b->mtu);
2243 
2244 			/* Update MTU for node link entry */
2245 			e->mtu = tipc_link_mss(e->link);
2246 		}
2247 
2248 		tipc_node_write_unlock(n);
2249 		tipc_bearer_xmit(net, bearer_id, &xmitq, &e->maddr, NULL);
2250 	}
2251 
2252 	rcu_read_unlock();
2253 }
2254 
2255 int tipc_nl_peer_rm(struct sk_buff *skb, struct genl_info *info)
2256 {
2257 	struct net *net = sock_net(skb->sk);
2258 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2259 	struct nlattr *attrs[TIPC_NLA_NET_MAX + 1];
2260 	struct tipc_node *peer, *temp_node;
2261 	u8 node_id[NODE_ID_LEN];
2262 	u64 *w0 = (u64 *)&node_id[0];
2263 	u64 *w1 = (u64 *)&node_id[8];
2264 	u32 addr;
2265 	int err;
2266 
2267 	/* We identify the peer by its net */
2268 	if (!info->attrs[TIPC_NLA_NET])
2269 		return -EINVAL;
2270 
2271 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_NET_MAX,
2272 					  info->attrs[TIPC_NLA_NET],
2273 					  tipc_nl_net_policy, info->extack);
2274 	if (err)
2275 		return err;
2276 
2277 	/* attrs[TIPC_NLA_NET_NODEID] and attrs[TIPC_NLA_NET_ADDR] are
2278 	 * mutually exclusive cases
2279 	 */
2280 	if (attrs[TIPC_NLA_NET_ADDR]) {
2281 		addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]);
2282 		if (!addr)
2283 			return -EINVAL;
2284 	}
2285 
2286 	if (attrs[TIPC_NLA_NET_NODEID]) {
2287 		if (!attrs[TIPC_NLA_NET_NODEID_W1])
2288 			return -EINVAL;
2289 		*w0 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID]);
2290 		*w1 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID_W1]);
2291 		addr = hash128to32(node_id);
2292 	}
2293 
2294 	if (in_own_node(net, addr))
2295 		return -ENOTSUPP;
2296 
2297 	spin_lock_bh(&tn->node_list_lock);
2298 	peer = tipc_node_find(net, addr);
2299 	if (!peer) {
2300 		spin_unlock_bh(&tn->node_list_lock);
2301 		return -ENXIO;
2302 	}
2303 
2304 	tipc_node_write_lock(peer);
2305 	if (peer->state != SELF_DOWN_PEER_DOWN &&
2306 	    peer->state != SELF_DOWN_PEER_LEAVING) {
2307 		tipc_node_write_unlock(peer);
2308 		err = -EBUSY;
2309 		goto err_out;
2310 	}
2311 
2312 	tipc_node_clear_links(peer);
2313 	tipc_node_write_unlock(peer);
2314 	tipc_node_delete(peer);
2315 
2316 	/* Calculate cluster capabilities */
2317 	tn->capabilities = TIPC_NODE_CAPABILITIES;
2318 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
2319 		tn->capabilities &= temp_node->capabilities;
2320 	}
2321 	tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
2322 	err = 0;
2323 err_out:
2324 	tipc_node_put(peer);
2325 	spin_unlock_bh(&tn->node_list_lock);
2326 
2327 	return err;
2328 }
2329 
2330 int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb)
2331 {
2332 	int err;
2333 	struct net *net = sock_net(skb->sk);
2334 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2335 	int done = cb->args[0];
2336 	int last_addr = cb->args[1];
2337 	struct tipc_node *node;
2338 	struct tipc_nl_msg msg;
2339 
2340 	if (done)
2341 		return 0;
2342 
2343 	msg.skb = skb;
2344 	msg.portid = NETLINK_CB(cb->skb).portid;
2345 	msg.seq = cb->nlh->nlmsg_seq;
2346 
2347 	rcu_read_lock();
2348 	if (last_addr) {
2349 		node = tipc_node_find(net, last_addr);
2350 		if (!node) {
2351 			rcu_read_unlock();
2352 			/* We never set seq or call nl_dump_check_consistent()
2353 			 * this means that setting prev_seq here will cause the
2354 			 * consistence check to fail in the netlink callback
2355 			 * handler. Resulting in the NLMSG_DONE message having
2356 			 * the NLM_F_DUMP_INTR flag set if the node state
2357 			 * changed while we released the lock.
2358 			 */
2359 			cb->prev_seq = 1;
2360 			return -EPIPE;
2361 		}
2362 		tipc_node_put(node);
2363 	}
2364 
2365 	list_for_each_entry_rcu(node, &tn->node_list, list) {
2366 		if (node->preliminary)
2367 			continue;
2368 		if (last_addr) {
2369 			if (node->addr == last_addr)
2370 				last_addr = 0;
2371 			else
2372 				continue;
2373 		}
2374 
2375 		tipc_node_read_lock(node);
2376 		err = __tipc_nl_add_node(&msg, node);
2377 		if (err) {
2378 			last_addr = node->addr;
2379 			tipc_node_read_unlock(node);
2380 			goto out;
2381 		}
2382 
2383 		tipc_node_read_unlock(node);
2384 	}
2385 	done = 1;
2386 out:
2387 	cb->args[0] = done;
2388 	cb->args[1] = last_addr;
2389 	rcu_read_unlock();
2390 
2391 	return skb->len;
2392 }
2393 
2394 /* tipc_node_find_by_name - locate owner node of link by link's name
2395  * @net: the applicable net namespace
2396  * @name: pointer to link name string
2397  * @bearer_id: pointer to index in 'node->links' array where the link was found.
2398  *
2399  * Returns pointer to node owning the link, or 0 if no matching link is found.
2400  */
2401 static struct tipc_node *tipc_node_find_by_name(struct net *net,
2402 						const char *link_name,
2403 						unsigned int *bearer_id)
2404 {
2405 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2406 	struct tipc_link *l;
2407 	struct tipc_node *n;
2408 	struct tipc_node *found_node = NULL;
2409 	int i;
2410 
2411 	*bearer_id = 0;
2412 	rcu_read_lock();
2413 	list_for_each_entry_rcu(n, &tn->node_list, list) {
2414 		tipc_node_read_lock(n);
2415 		for (i = 0; i < MAX_BEARERS; i++) {
2416 			l = n->links[i].link;
2417 			if (l && !strcmp(tipc_link_name(l), link_name)) {
2418 				*bearer_id = i;
2419 				found_node = n;
2420 				break;
2421 			}
2422 		}
2423 		tipc_node_read_unlock(n);
2424 		if (found_node)
2425 			break;
2426 	}
2427 	rcu_read_unlock();
2428 
2429 	return found_node;
2430 }
2431 
2432 int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info)
2433 {
2434 	int err;
2435 	int res = 0;
2436 	int bearer_id;
2437 	char *name;
2438 	struct tipc_link *link;
2439 	struct tipc_node *node;
2440 	struct sk_buff_head xmitq;
2441 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2442 	struct net *net = sock_net(skb->sk);
2443 
2444 	__skb_queue_head_init(&xmitq);
2445 
2446 	if (!info->attrs[TIPC_NLA_LINK])
2447 		return -EINVAL;
2448 
2449 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2450 					  info->attrs[TIPC_NLA_LINK],
2451 					  tipc_nl_link_policy, info->extack);
2452 	if (err)
2453 		return err;
2454 
2455 	if (!attrs[TIPC_NLA_LINK_NAME])
2456 		return -EINVAL;
2457 
2458 	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2459 
2460 	if (strcmp(name, tipc_bclink_name) == 0)
2461 		return tipc_nl_bc_link_set(net, attrs);
2462 
2463 	node = tipc_node_find_by_name(net, name, &bearer_id);
2464 	if (!node)
2465 		return -EINVAL;
2466 
2467 	tipc_node_read_lock(node);
2468 
2469 	link = node->links[bearer_id].link;
2470 	if (!link) {
2471 		res = -EINVAL;
2472 		goto out;
2473 	}
2474 
2475 	if (attrs[TIPC_NLA_LINK_PROP]) {
2476 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
2477 
2478 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP], props);
2479 		if (err) {
2480 			res = err;
2481 			goto out;
2482 		}
2483 
2484 		if (props[TIPC_NLA_PROP_TOL]) {
2485 			u32 tol;
2486 
2487 			tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2488 			tipc_link_set_tolerance(link, tol, &xmitq);
2489 		}
2490 		if (props[TIPC_NLA_PROP_PRIO]) {
2491 			u32 prio;
2492 
2493 			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2494 			tipc_link_set_prio(link, prio, &xmitq);
2495 		}
2496 		if (props[TIPC_NLA_PROP_WIN]) {
2497 			u32 max_win;
2498 
2499 			max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2500 			tipc_link_set_queue_limits(link,
2501 						   tipc_link_min_win(link),
2502 						   max_win);
2503 		}
2504 	}
2505 
2506 out:
2507 	tipc_node_read_unlock(node);
2508 	tipc_bearer_xmit(net, bearer_id, &xmitq, &node->links[bearer_id].maddr,
2509 			 NULL);
2510 	return res;
2511 }
2512 
2513 int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info)
2514 {
2515 	struct net *net = genl_info_net(info);
2516 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2517 	struct tipc_nl_msg msg;
2518 	char *name;
2519 	int err;
2520 
2521 	msg.portid = info->snd_portid;
2522 	msg.seq = info->snd_seq;
2523 
2524 	if (!info->attrs[TIPC_NLA_LINK])
2525 		return -EINVAL;
2526 
2527 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2528 					  info->attrs[TIPC_NLA_LINK],
2529 					  tipc_nl_link_policy, info->extack);
2530 	if (err)
2531 		return err;
2532 
2533 	if (!attrs[TIPC_NLA_LINK_NAME])
2534 		return -EINVAL;
2535 
2536 	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2537 
2538 	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2539 	if (!msg.skb)
2540 		return -ENOMEM;
2541 
2542 	if (strcmp(name, tipc_bclink_name) == 0) {
2543 		err = tipc_nl_add_bc_link(net, &msg, tipc_net(net)->bcl);
2544 		if (err)
2545 			goto err_free;
2546 	} else {
2547 		int bearer_id;
2548 		struct tipc_node *node;
2549 		struct tipc_link *link;
2550 
2551 		node = tipc_node_find_by_name(net, name, &bearer_id);
2552 		if (!node) {
2553 			err = -EINVAL;
2554 			goto err_free;
2555 		}
2556 
2557 		tipc_node_read_lock(node);
2558 		link = node->links[bearer_id].link;
2559 		if (!link) {
2560 			tipc_node_read_unlock(node);
2561 			err = -EINVAL;
2562 			goto err_free;
2563 		}
2564 
2565 		err = __tipc_nl_add_link(net, &msg, link, 0);
2566 		tipc_node_read_unlock(node);
2567 		if (err)
2568 			goto err_free;
2569 	}
2570 
2571 	return genlmsg_reply(msg.skb, info);
2572 
2573 err_free:
2574 	nlmsg_free(msg.skb);
2575 	return err;
2576 }
2577 
2578 int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info)
2579 {
2580 	int err;
2581 	char *link_name;
2582 	unsigned int bearer_id;
2583 	struct tipc_link *link;
2584 	struct tipc_node *node;
2585 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2586 	struct net *net = sock_net(skb->sk);
2587 	struct tipc_net *tn = tipc_net(net);
2588 	struct tipc_link_entry *le;
2589 
2590 	if (!info->attrs[TIPC_NLA_LINK])
2591 		return -EINVAL;
2592 
2593 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2594 					  info->attrs[TIPC_NLA_LINK],
2595 					  tipc_nl_link_policy, info->extack);
2596 	if (err)
2597 		return err;
2598 
2599 	if (!attrs[TIPC_NLA_LINK_NAME])
2600 		return -EINVAL;
2601 
2602 	link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2603 
2604 	err = -EINVAL;
2605 	if (!strcmp(link_name, tipc_bclink_name)) {
2606 		err = tipc_bclink_reset_stats(net, tipc_bc_sndlink(net));
2607 		if (err)
2608 			return err;
2609 		return 0;
2610 	} else if (strstr(link_name, tipc_bclink_name)) {
2611 		rcu_read_lock();
2612 		list_for_each_entry_rcu(node, &tn->node_list, list) {
2613 			tipc_node_read_lock(node);
2614 			link = node->bc_entry.link;
2615 			if (link && !strcmp(link_name, tipc_link_name(link))) {
2616 				err = tipc_bclink_reset_stats(net, link);
2617 				tipc_node_read_unlock(node);
2618 				break;
2619 			}
2620 			tipc_node_read_unlock(node);
2621 		}
2622 		rcu_read_unlock();
2623 		return err;
2624 	}
2625 
2626 	node = tipc_node_find_by_name(net, link_name, &bearer_id);
2627 	if (!node)
2628 		return -EINVAL;
2629 
2630 	le = &node->links[bearer_id];
2631 	tipc_node_read_lock(node);
2632 	spin_lock_bh(&le->lock);
2633 	link = node->links[bearer_id].link;
2634 	if (!link) {
2635 		spin_unlock_bh(&le->lock);
2636 		tipc_node_read_unlock(node);
2637 		return -EINVAL;
2638 	}
2639 	tipc_link_reset_stats(link);
2640 	spin_unlock_bh(&le->lock);
2641 	tipc_node_read_unlock(node);
2642 	return 0;
2643 }
2644 
2645 /* Caller should hold node lock  */
2646 static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
2647 				    struct tipc_node *node, u32 *prev_link,
2648 				    bool bc_link)
2649 {
2650 	u32 i;
2651 	int err;
2652 
2653 	for (i = *prev_link; i < MAX_BEARERS; i++) {
2654 		*prev_link = i;
2655 
2656 		if (!node->links[i].link)
2657 			continue;
2658 
2659 		err = __tipc_nl_add_link(net, msg,
2660 					 node->links[i].link, NLM_F_MULTI);
2661 		if (err)
2662 			return err;
2663 	}
2664 
2665 	if (bc_link) {
2666 		*prev_link = i;
2667 		err = tipc_nl_add_bc_link(net, msg, node->bc_entry.link);
2668 		if (err)
2669 			return err;
2670 	}
2671 
2672 	*prev_link = 0;
2673 
2674 	return 0;
2675 }
2676 
2677 int tipc_nl_node_dump_link(struct sk_buff *skb, struct netlink_callback *cb)
2678 {
2679 	struct net *net = sock_net(skb->sk);
2680 	struct nlattr **attrs = genl_dumpit_info(cb)->info.attrs;
2681 	struct nlattr *link[TIPC_NLA_LINK_MAX + 1];
2682 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2683 	struct tipc_node *node;
2684 	struct tipc_nl_msg msg;
2685 	u32 prev_node = cb->args[0];
2686 	u32 prev_link = cb->args[1];
2687 	int done = cb->args[2];
2688 	bool bc_link = cb->args[3];
2689 	int err;
2690 
2691 	if (done)
2692 		return 0;
2693 
2694 	if (!prev_node) {
2695 		/* Check if broadcast-receiver links dumping is needed */
2696 		if (attrs && attrs[TIPC_NLA_LINK]) {
2697 			err = nla_parse_nested_deprecated(link,
2698 							  TIPC_NLA_LINK_MAX,
2699 							  attrs[TIPC_NLA_LINK],
2700 							  tipc_nl_link_policy,
2701 							  NULL);
2702 			if (unlikely(err))
2703 				return err;
2704 			if (unlikely(!link[TIPC_NLA_LINK_BROADCAST]))
2705 				return -EINVAL;
2706 			bc_link = true;
2707 		}
2708 	}
2709 
2710 	msg.skb = skb;
2711 	msg.portid = NETLINK_CB(cb->skb).portid;
2712 	msg.seq = cb->nlh->nlmsg_seq;
2713 
2714 	rcu_read_lock();
2715 	if (prev_node) {
2716 		node = tipc_node_find(net, prev_node);
2717 		if (!node) {
2718 			/* We never set seq or call nl_dump_check_consistent()
2719 			 * this means that setting prev_seq here will cause the
2720 			 * consistence check to fail in the netlink callback
2721 			 * handler. Resulting in the last NLMSG_DONE message
2722 			 * having the NLM_F_DUMP_INTR flag set.
2723 			 */
2724 			cb->prev_seq = 1;
2725 			goto out;
2726 		}
2727 		tipc_node_put(node);
2728 
2729 		list_for_each_entry_continue_rcu(node, &tn->node_list,
2730 						 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 	} else {
2741 		err = tipc_nl_add_bc_link(net, &msg, tn->bcl);
2742 		if (err)
2743 			goto out;
2744 
2745 		list_for_each_entry_rcu(node, &tn->node_list, list) {
2746 			tipc_node_read_lock(node);
2747 			err = __tipc_nl_add_node_links(net, &msg, node,
2748 						       &prev_link, bc_link);
2749 			tipc_node_read_unlock(node);
2750 			if (err)
2751 				goto out;
2752 
2753 			prev_node = node->addr;
2754 		}
2755 	}
2756 	done = 1;
2757 out:
2758 	rcu_read_unlock();
2759 
2760 	cb->args[0] = prev_node;
2761 	cb->args[1] = prev_link;
2762 	cb->args[2] = done;
2763 	cb->args[3] = bc_link;
2764 
2765 	return skb->len;
2766 }
2767 
2768 int tipc_nl_node_set_monitor(struct sk_buff *skb, struct genl_info *info)
2769 {
2770 	struct nlattr *attrs[TIPC_NLA_MON_MAX + 1];
2771 	struct net *net = sock_net(skb->sk);
2772 	int err;
2773 
2774 	if (!info->attrs[TIPC_NLA_MON])
2775 		return -EINVAL;
2776 
2777 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_MON_MAX,
2778 					  info->attrs[TIPC_NLA_MON],
2779 					  tipc_nl_monitor_policy,
2780 					  info->extack);
2781 	if (err)
2782 		return err;
2783 
2784 	if (attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]) {
2785 		u32 val;
2786 
2787 		val = nla_get_u32(attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]);
2788 		err = tipc_nl_monitor_set_threshold(net, val);
2789 		if (err)
2790 			return err;
2791 	}
2792 
2793 	return 0;
2794 }
2795 
2796 static int __tipc_nl_add_monitor_prop(struct net *net, struct tipc_nl_msg *msg)
2797 {
2798 	struct nlattr *attrs;
2799 	void *hdr;
2800 	u32 val;
2801 
2802 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2803 			  0, TIPC_NL_MON_GET);
2804 	if (!hdr)
2805 		return -EMSGSIZE;
2806 
2807 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_MON);
2808 	if (!attrs)
2809 		goto msg_full;
2810 
2811 	val = tipc_nl_monitor_get_threshold(net);
2812 
2813 	if (nla_put_u32(msg->skb, TIPC_NLA_MON_ACTIVATION_THRESHOLD, val))
2814 		goto attr_msg_full;
2815 
2816 	nla_nest_end(msg->skb, attrs);
2817 	genlmsg_end(msg->skb, hdr);
2818 
2819 	return 0;
2820 
2821 attr_msg_full:
2822 	nla_nest_cancel(msg->skb, attrs);
2823 msg_full:
2824 	genlmsg_cancel(msg->skb, hdr);
2825 
2826 	return -EMSGSIZE;
2827 }
2828 
2829 int tipc_nl_node_get_monitor(struct sk_buff *skb, struct genl_info *info)
2830 {
2831 	struct net *net = sock_net(skb->sk);
2832 	struct tipc_nl_msg msg;
2833 	int err;
2834 
2835 	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2836 	if (!msg.skb)
2837 		return -ENOMEM;
2838 	msg.portid = info->snd_portid;
2839 	msg.seq = info->snd_seq;
2840 
2841 	err = __tipc_nl_add_monitor_prop(net, &msg);
2842 	if (err) {
2843 		nlmsg_free(msg.skb);
2844 		return err;
2845 	}
2846 
2847 	return genlmsg_reply(msg.skb, info);
2848 }
2849 
2850 int tipc_nl_node_dump_monitor(struct sk_buff *skb, struct netlink_callback *cb)
2851 {
2852 	struct net *net = sock_net(skb->sk);
2853 	u32 prev_bearer = cb->args[0];
2854 	struct tipc_nl_msg msg;
2855 	int bearer_id;
2856 	int err;
2857 
2858 	if (prev_bearer == MAX_BEARERS)
2859 		return 0;
2860 
2861 	msg.skb = skb;
2862 	msg.portid = NETLINK_CB(cb->skb).portid;
2863 	msg.seq = cb->nlh->nlmsg_seq;
2864 
2865 	rtnl_lock();
2866 	for (bearer_id = prev_bearer; bearer_id < MAX_BEARERS; bearer_id++) {
2867 		err = __tipc_nl_add_monitor(net, &msg, bearer_id);
2868 		if (err)
2869 			break;
2870 	}
2871 	rtnl_unlock();
2872 	cb->args[0] = bearer_id;
2873 
2874 	return skb->len;
2875 }
2876 
2877 int tipc_nl_node_dump_monitor_peer(struct sk_buff *skb,
2878 				   struct netlink_callback *cb)
2879 {
2880 	struct net *net = sock_net(skb->sk);
2881 	u32 prev_node = cb->args[1];
2882 	u32 bearer_id = cb->args[2];
2883 	int done = cb->args[0];
2884 	struct tipc_nl_msg msg;
2885 	int err;
2886 
2887 	if (!prev_node) {
2888 		struct nlattr **attrs = genl_dumpit_info(cb)->info.attrs;
2889 		struct nlattr *mon[TIPC_NLA_MON_MAX + 1];
2890 
2891 		if (!attrs[TIPC_NLA_MON])
2892 			return -EINVAL;
2893 
2894 		err = nla_parse_nested_deprecated(mon, TIPC_NLA_MON_MAX,
2895 						  attrs[TIPC_NLA_MON],
2896 						  tipc_nl_monitor_policy,
2897 						  NULL);
2898 		if (err)
2899 			return err;
2900 
2901 		if (!mon[TIPC_NLA_MON_REF])
2902 			return -EINVAL;
2903 
2904 		bearer_id = nla_get_u32(mon[TIPC_NLA_MON_REF]);
2905 
2906 		if (bearer_id >= MAX_BEARERS)
2907 			return -EINVAL;
2908 	}
2909 
2910 	if (done)
2911 		return 0;
2912 
2913 	msg.skb = skb;
2914 	msg.portid = NETLINK_CB(cb->skb).portid;
2915 	msg.seq = cb->nlh->nlmsg_seq;
2916 
2917 	rtnl_lock();
2918 	err = tipc_nl_add_monitor_peer(net, &msg, bearer_id, &prev_node);
2919 	if (!err)
2920 		done = 1;
2921 
2922 	rtnl_unlock();
2923 	cb->args[0] = done;
2924 	cb->args[1] = prev_node;
2925 	cb->args[2] = bearer_id;
2926 
2927 	return skb->len;
2928 }
2929 
2930 #ifdef CONFIG_TIPC_CRYPTO
2931 static int tipc_nl_retrieve_key(struct nlattr **attrs,
2932 				struct tipc_aead_key **pkey)
2933 {
2934 	struct nlattr *attr = attrs[TIPC_NLA_NODE_KEY];
2935 	struct tipc_aead_key *key;
2936 
2937 	if (!attr)
2938 		return -ENODATA;
2939 
2940 	if (nla_len(attr) < sizeof(*key))
2941 		return -EINVAL;
2942 	key = (struct tipc_aead_key *)nla_data(attr);
2943 	if (key->keylen > TIPC_AEAD_KEYLEN_MAX ||
2944 	    nla_len(attr) < tipc_aead_key_size(key))
2945 		return -EINVAL;
2946 
2947 	*pkey = key;
2948 	return 0;
2949 }
2950 
2951 static int tipc_nl_retrieve_nodeid(struct nlattr **attrs, u8 **node_id)
2952 {
2953 	struct nlattr *attr = attrs[TIPC_NLA_NODE_ID];
2954 
2955 	if (!attr)
2956 		return -ENODATA;
2957 
2958 	if (nla_len(attr) < TIPC_NODEID_LEN)
2959 		return -EINVAL;
2960 
2961 	*node_id = (u8 *)nla_data(attr);
2962 	return 0;
2963 }
2964 
2965 static int tipc_nl_retrieve_rekeying(struct nlattr **attrs, u32 *intv)
2966 {
2967 	struct nlattr *attr = attrs[TIPC_NLA_NODE_REKEYING];
2968 
2969 	if (!attr)
2970 		return -ENODATA;
2971 
2972 	*intv = nla_get_u32(attr);
2973 	return 0;
2974 }
2975 
2976 static int __tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
2977 {
2978 	struct nlattr *attrs[TIPC_NLA_NODE_MAX + 1];
2979 	struct net *net = sock_net(skb->sk);
2980 	struct tipc_crypto *tx = tipc_net(net)->crypto_tx, *c = tx;
2981 	struct tipc_node *n = NULL;
2982 	struct tipc_aead_key *ukey;
2983 	bool rekeying = true, master_key = false;
2984 	u8 *id, *own_id, mode;
2985 	u32 intv = 0;
2986 	int rc = 0;
2987 
2988 	if (!info->attrs[TIPC_NLA_NODE])
2989 		return -EINVAL;
2990 
2991 	rc = nla_parse_nested(attrs, TIPC_NLA_NODE_MAX,
2992 			      info->attrs[TIPC_NLA_NODE],
2993 			      tipc_nl_node_policy, info->extack);
2994 	if (rc)
2995 		return rc;
2996 
2997 	own_id = tipc_own_id(net);
2998 	if (!own_id) {
2999 		GENL_SET_ERR_MSG(info, "not found own node identity (set id?)");
3000 		return -EPERM;
3001 	}
3002 
3003 	rc = tipc_nl_retrieve_rekeying(attrs, &intv);
3004 	if (rc == -ENODATA)
3005 		rekeying = false;
3006 
3007 	rc = tipc_nl_retrieve_key(attrs, &ukey);
3008 	if (rc == -ENODATA && rekeying)
3009 		goto rekeying;
3010 	else if (rc)
3011 		return rc;
3012 
3013 	rc = tipc_aead_key_validate(ukey, info);
3014 	if (rc)
3015 		return rc;
3016 
3017 	rc = tipc_nl_retrieve_nodeid(attrs, &id);
3018 	switch (rc) {
3019 	case -ENODATA:
3020 		mode = CLUSTER_KEY;
3021 		master_key = !!(attrs[TIPC_NLA_NODE_KEY_MASTER]);
3022 		break;
3023 	case 0:
3024 		mode = PER_NODE_KEY;
3025 		if (memcmp(id, own_id, NODE_ID_LEN)) {
3026 			n = tipc_node_find_by_id(net, id) ?:
3027 				tipc_node_create(net, 0, id, 0xffffu, 0, true);
3028 			if (unlikely(!n))
3029 				return -ENOMEM;
3030 			c = n->crypto_rx;
3031 		}
3032 		break;
3033 	default:
3034 		return rc;
3035 	}
3036 
3037 	/* Initiate the TX/RX key */
3038 	rc = tipc_crypto_key_init(c, ukey, mode, master_key);
3039 	if (n)
3040 		tipc_node_put(n);
3041 
3042 	if (unlikely(rc < 0)) {
3043 		GENL_SET_ERR_MSG(info, "unable to initiate or attach new key");
3044 		return rc;
3045 	} else if (c == tx) {
3046 		/* Distribute TX key but not master one */
3047 		if (!master_key && tipc_crypto_key_distr(tx, rc, NULL))
3048 			GENL_SET_ERR_MSG(info, "failed to replicate new key");
3049 rekeying:
3050 		/* Schedule TX rekeying if needed */
3051 		tipc_crypto_rekeying_sched(tx, rekeying, intv);
3052 	}
3053 
3054 	return 0;
3055 }
3056 
3057 int tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
3058 {
3059 	int err;
3060 
3061 	rtnl_lock();
3062 	err = __tipc_nl_node_set_key(skb, info);
3063 	rtnl_unlock();
3064 
3065 	return err;
3066 }
3067 
3068 static int __tipc_nl_node_flush_key(struct sk_buff *skb,
3069 				    struct genl_info *info)
3070 {
3071 	struct net *net = sock_net(skb->sk);
3072 	struct tipc_net *tn = tipc_net(net);
3073 	struct tipc_node *n;
3074 
3075 	tipc_crypto_key_flush(tn->crypto_tx);
3076 	rcu_read_lock();
3077 	list_for_each_entry_rcu(n, &tn->node_list, list)
3078 		tipc_crypto_key_flush(n->crypto_rx);
3079 	rcu_read_unlock();
3080 
3081 	return 0;
3082 }
3083 
3084 int tipc_nl_node_flush_key(struct sk_buff *skb, struct genl_info *info)
3085 {
3086 	int err;
3087 
3088 	rtnl_lock();
3089 	err = __tipc_nl_node_flush_key(skb, info);
3090 	rtnl_unlock();
3091 
3092 	return err;
3093 }
3094 #endif
3095 
3096 /**
3097  * tipc_node_dump - dump TIPC node data
3098  * @n: tipc node to be dumped
3099  * @more: dump more?
3100  *        - false: dump only tipc node data
3101  *        - true: dump node link data as well
3102  * @buf: returned buffer of dump data in format
3103  */
3104 int tipc_node_dump(struct tipc_node *n, bool more, char *buf)
3105 {
3106 	int i = 0;
3107 	size_t sz = (more) ? NODE_LMAX : NODE_LMIN;
3108 
3109 	if (!n) {
3110 		i += scnprintf(buf, sz, "node data: (null)\n");
3111 		return i;
3112 	}
3113 
3114 	i += scnprintf(buf, sz, "node data: %x", n->addr);
3115 	i += scnprintf(buf + i, sz - i, " %x", n->state);
3116 	i += scnprintf(buf + i, sz - i, " %d", n->active_links[0]);
3117 	i += scnprintf(buf + i, sz - i, " %d", n->active_links[1]);
3118 	i += scnprintf(buf + i, sz - i, " %x", n->action_flags);
3119 	i += scnprintf(buf + i, sz - i, " %u", n->failover_sent);
3120 	i += scnprintf(buf + i, sz - i, " %u", n->sync_point);
3121 	i += scnprintf(buf + i, sz - i, " %d", n->link_cnt);
3122 	i += scnprintf(buf + i, sz - i, " %u", n->working_links);
3123 	i += scnprintf(buf + i, sz - i, " %x", n->capabilities);
3124 	i += scnprintf(buf + i, sz - i, " %lu\n", n->keepalive_intv);
3125 
3126 	if (!more)
3127 		return i;
3128 
3129 	i += scnprintf(buf + i, sz - i, "link_entry[0]:\n");
3130 	i += scnprintf(buf + i, sz - i, " mtu: %u\n", n->links[0].mtu);
3131 	i += scnprintf(buf + i, sz - i, " media: ");
3132 	i += tipc_media_addr_printf(buf + i, sz - i, &n->links[0].maddr);
3133 	i += scnprintf(buf + i, sz - i, "\n");
3134 	i += tipc_link_dump(n->links[0].link, TIPC_DUMP_NONE, buf + i);
3135 	i += scnprintf(buf + i, sz - i, " inputq: ");
3136 	i += tipc_list_dump(&n->links[0].inputq, false, buf + i);
3137 
3138 	i += scnprintf(buf + i, sz - i, "link_entry[1]:\n");
3139 	i += scnprintf(buf + i, sz - i, " mtu: %u\n", n->links[1].mtu);
3140 	i += scnprintf(buf + i, sz - i, " media: ");
3141 	i += tipc_media_addr_printf(buf + i, sz - i, &n->links[1].maddr);
3142 	i += scnprintf(buf + i, sz - i, "\n");
3143 	i += tipc_link_dump(n->links[1].link, TIPC_DUMP_NONE, buf + i);
3144 	i += scnprintf(buf + i, sz - i, " inputq: ");
3145 	i += tipc_list_dump(&n->links[1].inputq, false, buf + i);
3146 
3147 	i += scnprintf(buf + i, sz - i, "bclink:\n ");
3148 	i += tipc_link_dump(n->bc_entry.link, TIPC_DUMP_NONE, buf + i);
3149 
3150 	return i;
3151 }
3152 
3153 void tipc_node_pre_cleanup_net(struct net *exit_net)
3154 {
3155 	struct tipc_node *n;
3156 	struct tipc_net *tn;
3157 	struct net *tmp;
3158 
3159 	rcu_read_lock();
3160 	for_each_net_rcu(tmp) {
3161 		if (tmp == exit_net)
3162 			continue;
3163 		tn = tipc_net(tmp);
3164 		if (!tn)
3165 			continue;
3166 		spin_lock_bh(&tn->node_list_lock);
3167 		list_for_each_entry_rcu(n, &tn->node_list, list) {
3168 			if (!n->peer_net)
3169 				continue;
3170 			if (n->peer_net != exit_net)
3171 				continue;
3172 			tipc_node_write_lock(n);
3173 			n->peer_net = NULL;
3174 			n->peer_hash_mix = 0;
3175 			tipc_node_write_unlock_fast(n);
3176 			break;
3177 		}
3178 		spin_unlock_bh(&tn->node_list_lock);
3179 	}
3180 	rcu_read_unlock();
3181 }
3182