xref: /openbmc/linux/net/tipc/node.c (revision 2cf1c348)
1 /*
2  * net/tipc/node.c: TIPC node management routines
3  *
4  * Copyright (c) 2000-2006, 2012-2016, Ericsson AB
5  * Copyright (c) 2005-2006, 2010-2014, Wind River Systems
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the names of the copyright holders nor the names of its
17  *    contributors may be used to endorse or promote products derived from
18  *    this software without specific prior written permission.
19  *
20  * Alternatively, this software may be distributed under the terms of the
21  * GNU General Public License ("GPL") version 2 as published by the Free
22  * Software Foundation.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34  * POSSIBILITY OF SUCH DAMAGE.
35  */
36 
37 #include "core.h"
38 #include "link.h"
39 #include "node.h"
40 #include "name_distr.h"
41 #include "socket.h"
42 #include "bcast.h"
43 #include "monitor.h"
44 #include "discover.h"
45 #include "netlink.h"
46 #include "trace.h"
47 #include "crypto.h"
48 
49 #define INVALID_NODE_SIG	0x10000
50 #define NODE_CLEANUP_AFTER	300000
51 
52 /* Flags used to take different actions according to flag type
53  * TIPC_NOTIFY_NODE_DOWN: notify node is down
54  * TIPC_NOTIFY_NODE_UP: notify node is up
55  * TIPC_DISTRIBUTE_NAME: publish or withdraw link state name type
56  */
57 enum {
58 	TIPC_NOTIFY_NODE_DOWN		= (1 << 3),
59 	TIPC_NOTIFY_NODE_UP		= (1 << 4),
60 	TIPC_NOTIFY_LINK_UP		= (1 << 6),
61 	TIPC_NOTIFY_LINK_DOWN		= (1 << 7)
62 };
63 
64 struct tipc_link_entry {
65 	struct tipc_link *link;
66 	spinlock_t lock; /* per link */
67 	u32 mtu;
68 	struct sk_buff_head inputq;
69 	struct tipc_media_addr maddr;
70 };
71 
72 struct tipc_bclink_entry {
73 	struct tipc_link *link;
74 	struct sk_buff_head inputq1;
75 	struct sk_buff_head arrvq;
76 	struct sk_buff_head inputq2;
77 	struct sk_buff_head namedq;
78 	u16 named_rcv_nxt;
79 	bool named_open;
80 };
81 
82 /**
83  * struct tipc_node - TIPC node structure
84  * @addr: network address of node
85  * @kref: reference counter to node object
86  * @lock: rwlock governing access to structure
87  * @net: the applicable net namespace
88  * @hash: links to adjacent nodes in unsorted hash chain
89  * @inputq: pointer to input queue containing messages for msg event
90  * @namedq: pointer to name table input queue with name table messages
91  * @active_links: bearer ids of active links, used as index into links[] array
92  * @links: array containing references to all links to node
93  * @bc_entry: broadcast link entry
94  * @action_flags: bit mask of different types of node actions
95  * @state: connectivity state vs peer node
96  * @preliminary: a preliminary node or not
97  * @failover_sent: failover sent or not
98  * @sync_point: sequence number where synch/failover is finished
99  * @list: links to adjacent nodes in sorted list of cluster's nodes
100  * @working_links: number of working links to node (both active and standby)
101  * @link_cnt: number of links to node
102  * @capabilities: bitmap, indicating peer node's functional capabilities
103  * @signature: node instance identifier
104  * @link_id: local and remote bearer ids of changing link, if any
105  * @peer_id: 128-bit ID of peer
106  * @peer_id_string: ID string of peer
107  * @publ_list: list of publications
108  * @conn_sks: list of connections (FIXME)
109  * @timer: node's keepalive timer
110  * @keepalive_intv: keepalive interval in milliseconds
111  * @rcu: rcu struct for tipc_node
112  * @delete_at: indicates the time for deleting a down node
113  * @peer_net: peer's net namespace
114  * @peer_hash_mix: hash for this peer (FIXME)
115  * @crypto_rx: RX crypto handler
116  */
117 struct tipc_node {
118 	u32 addr;
119 	struct kref kref;
120 	rwlock_t lock;
121 	struct net *net;
122 	struct hlist_node hash;
123 	int active_links[2];
124 	struct tipc_link_entry links[MAX_BEARERS];
125 	struct tipc_bclink_entry bc_entry;
126 	int action_flags;
127 	struct list_head list;
128 	int state;
129 	bool preliminary;
130 	bool failover_sent;
131 	u16 sync_point;
132 	int link_cnt;
133 	u16 working_links;
134 	u16 capabilities;
135 	u32 signature;
136 	u32 link_id;
137 	u8 peer_id[16];
138 	char peer_id_string[NODE_ID_STR_LEN];
139 	struct list_head publ_list;
140 	struct list_head conn_sks;
141 	unsigned long keepalive_intv;
142 	struct timer_list timer;
143 	struct rcu_head rcu;
144 	unsigned long delete_at;
145 	struct net *peer_net;
146 	u32 peer_hash_mix;
147 #ifdef CONFIG_TIPC_CRYPTO
148 	struct tipc_crypto *crypto_rx;
149 #endif
150 };
151 
152 /* Node FSM states and events:
153  */
154 enum {
155 	SELF_DOWN_PEER_DOWN    = 0xdd,
156 	SELF_UP_PEER_UP        = 0xaa,
157 	SELF_DOWN_PEER_LEAVING = 0xd1,
158 	SELF_UP_PEER_COMING    = 0xac,
159 	SELF_COMING_PEER_UP    = 0xca,
160 	SELF_LEAVING_PEER_DOWN = 0x1d,
161 	NODE_FAILINGOVER       = 0xf0,
162 	NODE_SYNCHING          = 0xcc
163 };
164 
165 enum {
166 	SELF_ESTABL_CONTACT_EVT = 0xece,
167 	SELF_LOST_CONTACT_EVT   = 0x1ce,
168 	PEER_ESTABL_CONTACT_EVT = 0x9ece,
169 	PEER_LOST_CONTACT_EVT   = 0x91ce,
170 	NODE_FAILOVER_BEGIN_EVT = 0xfbe,
171 	NODE_FAILOVER_END_EVT   = 0xfee,
172 	NODE_SYNCH_BEGIN_EVT    = 0xcbe,
173 	NODE_SYNCH_END_EVT      = 0xcee
174 };
175 
176 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
177 				  struct sk_buff_head *xmitq,
178 				  struct tipc_media_addr **maddr);
179 static void tipc_node_link_down(struct tipc_node *n, int bearer_id,
180 				bool delete);
181 static void node_lost_contact(struct tipc_node *n, struct sk_buff_head *inputq);
182 static void tipc_node_delete(struct tipc_node *node);
183 static void tipc_node_timeout(struct timer_list *t);
184 static void tipc_node_fsm_evt(struct tipc_node *n, int evt);
185 static struct tipc_node *tipc_node_find(struct net *net, u32 addr);
186 static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id);
187 static bool node_is_up(struct tipc_node *n);
188 static void tipc_node_delete_from_list(struct tipc_node *node);
189 
190 struct tipc_sock_conn {
191 	u32 port;
192 	u32 peer_port;
193 	u32 peer_node;
194 	struct list_head list;
195 };
196 
197 static struct tipc_link *node_active_link(struct tipc_node *n, int sel)
198 {
199 	int bearer_id = n->active_links[sel & 1];
200 
201 	if (unlikely(bearer_id == INVALID_BEARER_ID))
202 		return NULL;
203 
204 	return n->links[bearer_id].link;
205 }
206 
207 int tipc_node_get_mtu(struct net *net, u32 addr, u32 sel, bool connected)
208 {
209 	struct tipc_node *n;
210 	int bearer_id;
211 	unsigned int mtu = MAX_MSG_SIZE;
212 
213 	n = tipc_node_find(net, addr);
214 	if (unlikely(!n))
215 		return mtu;
216 
217 	/* Allow MAX_MSG_SIZE when building connection oriented message
218 	 * if they are in the same core network
219 	 */
220 	if (n->peer_net && connected) {
221 		tipc_node_put(n);
222 		return mtu;
223 	}
224 
225 	bearer_id = n->active_links[sel & 1];
226 	if (likely(bearer_id != INVALID_BEARER_ID))
227 		mtu = n->links[bearer_id].mtu;
228 	tipc_node_put(n);
229 	return mtu;
230 }
231 
232 bool tipc_node_get_id(struct net *net, u32 addr, u8 *id)
233 {
234 	u8 *own_id = tipc_own_id(net);
235 	struct tipc_node *n;
236 
237 	if (!own_id)
238 		return true;
239 
240 	if (addr == tipc_own_addr(net)) {
241 		memcpy(id, own_id, TIPC_NODEID_LEN);
242 		return true;
243 	}
244 	n = tipc_node_find(net, addr);
245 	if (!n)
246 		return false;
247 
248 	memcpy(id, &n->peer_id, TIPC_NODEID_LEN);
249 	tipc_node_put(n);
250 	return true;
251 }
252 
253 u16 tipc_node_get_capabilities(struct net *net, u32 addr)
254 {
255 	struct tipc_node *n;
256 	u16 caps;
257 
258 	n = tipc_node_find(net, addr);
259 	if (unlikely(!n))
260 		return TIPC_NODE_CAPABILITIES;
261 	caps = n->capabilities;
262 	tipc_node_put(n);
263 	return caps;
264 }
265 
266 u32 tipc_node_get_addr(struct tipc_node *node)
267 {
268 	return (node) ? node->addr : 0;
269 }
270 
271 char *tipc_node_get_id_str(struct tipc_node *node)
272 {
273 	return node->peer_id_string;
274 }
275 
276 #ifdef CONFIG_TIPC_CRYPTO
277 /**
278  * tipc_node_crypto_rx - Retrieve crypto RX handle from node
279  * @__n: target tipc_node
280  * Note: node ref counter must be held first!
281  */
282 struct tipc_crypto *tipc_node_crypto_rx(struct tipc_node *__n)
283 {
284 	return (__n) ? __n->crypto_rx : NULL;
285 }
286 
287 struct tipc_crypto *tipc_node_crypto_rx_by_list(struct list_head *pos)
288 {
289 	return container_of(pos, struct tipc_node, list)->crypto_rx;
290 }
291 
292 struct tipc_crypto *tipc_node_crypto_rx_by_addr(struct net *net, u32 addr)
293 {
294 	struct tipc_node *n;
295 
296 	n = tipc_node_find(net, addr);
297 	return (n) ? n->crypto_rx : NULL;
298 }
299 #endif
300 
301 static void tipc_node_free(struct rcu_head *rp)
302 {
303 	struct tipc_node *n = container_of(rp, struct tipc_node, rcu);
304 
305 #ifdef CONFIG_TIPC_CRYPTO
306 	tipc_crypto_stop(&n->crypto_rx);
307 #endif
308 	kfree(n);
309 }
310 
311 static void tipc_node_kref_release(struct kref *kref)
312 {
313 	struct tipc_node *n = container_of(kref, struct tipc_node, kref);
314 
315 	kfree(n->bc_entry.link);
316 	call_rcu(&n->rcu, tipc_node_free);
317 }
318 
319 void tipc_node_put(struct tipc_node *node)
320 {
321 	kref_put(&node->kref, tipc_node_kref_release);
322 }
323 
324 void tipc_node_get(struct tipc_node *node)
325 {
326 	kref_get(&node->kref);
327 }
328 
329 /*
330  * tipc_node_find - locate specified node object, if it exists
331  */
332 static struct tipc_node *tipc_node_find(struct net *net, u32 addr)
333 {
334 	struct tipc_net *tn = tipc_net(net);
335 	struct tipc_node *node;
336 	unsigned int thash = tipc_hashfn(addr);
337 
338 	rcu_read_lock();
339 	hlist_for_each_entry_rcu(node, &tn->node_htable[thash], hash) {
340 		if (node->addr != addr || node->preliminary)
341 			continue;
342 		if (!kref_get_unless_zero(&node->kref))
343 			node = NULL;
344 		break;
345 	}
346 	rcu_read_unlock();
347 	return node;
348 }
349 
350 /* tipc_node_find_by_id - locate specified node object by its 128-bit id
351  * Note: this function is called only when a discovery request failed
352  * to find the node by its 32-bit id, and is not time critical
353  */
354 static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id)
355 {
356 	struct tipc_net *tn = tipc_net(net);
357 	struct tipc_node *n;
358 	bool found = false;
359 
360 	rcu_read_lock();
361 	list_for_each_entry_rcu(n, &tn->node_list, list) {
362 		read_lock_bh(&n->lock);
363 		if (!memcmp(id, n->peer_id, 16) &&
364 		    kref_get_unless_zero(&n->kref))
365 			found = true;
366 		read_unlock_bh(&n->lock);
367 		if (found)
368 			break;
369 	}
370 	rcu_read_unlock();
371 	return found ? n : NULL;
372 }
373 
374 static void tipc_node_read_lock(struct tipc_node *n)
375 	__acquires(n->lock)
376 {
377 	read_lock_bh(&n->lock);
378 }
379 
380 static void tipc_node_read_unlock(struct tipc_node *n)
381 	__releases(n->lock)
382 {
383 	read_unlock_bh(&n->lock);
384 }
385 
386 static void tipc_node_write_lock(struct tipc_node *n)
387 	__acquires(n->lock)
388 {
389 	write_lock_bh(&n->lock);
390 }
391 
392 static void tipc_node_write_unlock_fast(struct tipc_node *n)
393 	__releases(n->lock)
394 {
395 	write_unlock_bh(&n->lock);
396 }
397 
398 static void tipc_node_write_unlock(struct tipc_node *n)
399 	__releases(n->lock)
400 {
401 	struct tipc_socket_addr sk;
402 	struct net *net = n->net;
403 	u32 flags = n->action_flags;
404 	struct list_head *publ_list;
405 	struct tipc_uaddr ua;
406 	u32 bearer_id;
407 
408 	if (likely(!flags)) {
409 		write_unlock_bh(&n->lock);
410 		return;
411 	}
412 
413 	tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_NODE_SCOPE,
414 		   TIPC_LINK_STATE, n->addr, n->addr);
415 	sk.ref = n->link_id;
416 	sk.node = n->addr;
417 	bearer_id = n->link_id & 0xffff;
418 	publ_list = &n->publ_list;
419 
420 	n->action_flags &= ~(TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP |
421 			     TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP);
422 
423 	write_unlock_bh(&n->lock);
424 
425 	if (flags & TIPC_NOTIFY_NODE_DOWN)
426 		tipc_publ_notify(net, publ_list, sk.node, n->capabilities);
427 
428 	if (flags & TIPC_NOTIFY_NODE_UP)
429 		tipc_named_node_up(net, sk.node, n->capabilities);
430 
431 	if (flags & TIPC_NOTIFY_LINK_UP) {
432 		tipc_mon_peer_up(net, sk.node, bearer_id);
433 		tipc_nametbl_publish(net, &ua, &sk, sk.ref);
434 	}
435 	if (flags & TIPC_NOTIFY_LINK_DOWN) {
436 		tipc_mon_peer_down(net, sk.node, bearer_id);
437 		tipc_nametbl_withdraw(net, &ua, &sk, sk.ref);
438 	}
439 }
440 
441 static void tipc_node_assign_peer_net(struct tipc_node *n, u32 hash_mixes)
442 {
443 	int net_id = tipc_netid(n->net);
444 	struct tipc_net *tn_peer;
445 	struct net *tmp;
446 	u32 hash_chk;
447 
448 	if (n->peer_net)
449 		return;
450 
451 	for_each_net_rcu(tmp) {
452 		tn_peer = tipc_net(tmp);
453 		if (!tn_peer)
454 			continue;
455 		/* Integrity checking whether node exists in namespace or not */
456 		if (tn_peer->net_id != net_id)
457 			continue;
458 		if (memcmp(n->peer_id, tn_peer->node_id, NODE_ID_LEN))
459 			continue;
460 		hash_chk = tipc_net_hash_mixes(tmp, tn_peer->random);
461 		if (hash_mixes ^ hash_chk)
462 			continue;
463 		n->peer_net = tmp;
464 		n->peer_hash_mix = hash_mixes;
465 		break;
466 	}
467 }
468 
469 struct tipc_node *tipc_node_create(struct net *net, u32 addr, u8 *peer_id,
470 				   u16 capabilities, u32 hash_mixes,
471 				   bool preliminary)
472 {
473 	struct tipc_net *tn = net_generic(net, tipc_net_id);
474 	struct tipc_node *n, *temp_node;
475 	struct tipc_link *l;
476 	unsigned long intv;
477 	int bearer_id;
478 	int i;
479 
480 	spin_lock_bh(&tn->node_list_lock);
481 	n = tipc_node_find(net, addr) ?:
482 		tipc_node_find_by_id(net, peer_id);
483 	if (n) {
484 		if (!n->preliminary)
485 			goto update;
486 		if (preliminary)
487 			goto exit;
488 		/* A preliminary node becomes "real" now, refresh its data */
489 		tipc_node_write_lock(n);
490 		n->preliminary = false;
491 		n->addr = addr;
492 		hlist_del_rcu(&n->hash);
493 		hlist_add_head_rcu(&n->hash,
494 				   &tn->node_htable[tipc_hashfn(addr)]);
495 		list_del_rcu(&n->list);
496 		list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
497 			if (n->addr < temp_node->addr)
498 				break;
499 		}
500 		list_add_tail_rcu(&n->list, &temp_node->list);
501 		tipc_node_write_unlock_fast(n);
502 
503 update:
504 		if (n->peer_hash_mix ^ hash_mixes)
505 			tipc_node_assign_peer_net(n, hash_mixes);
506 		if (n->capabilities == capabilities)
507 			goto exit;
508 		/* Same node may come back with new capabilities */
509 		tipc_node_write_lock(n);
510 		n->capabilities = capabilities;
511 		for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
512 			l = n->links[bearer_id].link;
513 			if (l)
514 				tipc_link_update_caps(l, capabilities);
515 		}
516 		tipc_node_write_unlock_fast(n);
517 
518 		/* Calculate cluster capabilities */
519 		tn->capabilities = TIPC_NODE_CAPABILITIES;
520 		list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
521 			tn->capabilities &= temp_node->capabilities;
522 		}
523 
524 		tipc_bcast_toggle_rcast(net,
525 					(tn->capabilities & TIPC_BCAST_RCAST));
526 
527 		goto exit;
528 	}
529 	n = kzalloc(sizeof(*n), GFP_ATOMIC);
530 	if (!n) {
531 		pr_warn("Node creation failed, no memory\n");
532 		goto exit;
533 	}
534 	tipc_nodeid2string(n->peer_id_string, peer_id);
535 #ifdef CONFIG_TIPC_CRYPTO
536 	if (unlikely(tipc_crypto_start(&n->crypto_rx, net, n))) {
537 		pr_warn("Failed to start crypto RX(%s)!\n", n->peer_id_string);
538 		kfree(n);
539 		n = NULL;
540 		goto exit;
541 	}
542 #endif
543 	n->addr = addr;
544 	n->preliminary = preliminary;
545 	memcpy(&n->peer_id, peer_id, 16);
546 	n->net = net;
547 	n->peer_net = NULL;
548 	n->peer_hash_mix = 0;
549 	/* Assign kernel local namespace if exists */
550 	tipc_node_assign_peer_net(n, hash_mixes);
551 	n->capabilities = capabilities;
552 	kref_init(&n->kref);
553 	rwlock_init(&n->lock);
554 	INIT_HLIST_NODE(&n->hash);
555 	INIT_LIST_HEAD(&n->list);
556 	INIT_LIST_HEAD(&n->publ_list);
557 	INIT_LIST_HEAD(&n->conn_sks);
558 	skb_queue_head_init(&n->bc_entry.namedq);
559 	skb_queue_head_init(&n->bc_entry.inputq1);
560 	__skb_queue_head_init(&n->bc_entry.arrvq);
561 	skb_queue_head_init(&n->bc_entry.inputq2);
562 	for (i = 0; i < MAX_BEARERS; i++)
563 		spin_lock_init(&n->links[i].lock);
564 	n->state = SELF_DOWN_PEER_LEAVING;
565 	n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
566 	n->signature = INVALID_NODE_SIG;
567 	n->active_links[0] = INVALID_BEARER_ID;
568 	n->active_links[1] = INVALID_BEARER_ID;
569 	n->bc_entry.link = NULL;
570 	tipc_node_get(n);
571 	timer_setup(&n->timer, tipc_node_timeout, 0);
572 	/* Start a slow timer anyway, crypto needs it */
573 	n->keepalive_intv = 10000;
574 	intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
575 	if (!mod_timer(&n->timer, intv))
576 		tipc_node_get(n);
577 	hlist_add_head_rcu(&n->hash, &tn->node_htable[tipc_hashfn(addr)]);
578 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
579 		if (n->addr < temp_node->addr)
580 			break;
581 	}
582 	list_add_tail_rcu(&n->list, &temp_node->list);
583 	/* Calculate cluster capabilities */
584 	tn->capabilities = TIPC_NODE_CAPABILITIES;
585 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
586 		tn->capabilities &= temp_node->capabilities;
587 	}
588 	tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
589 	trace_tipc_node_create(n, true, " ");
590 exit:
591 	spin_unlock_bh(&tn->node_list_lock);
592 	return n;
593 }
594 
595 static void tipc_node_calculate_timer(struct tipc_node *n, struct tipc_link *l)
596 {
597 	unsigned long tol = tipc_link_tolerance(l);
598 	unsigned long intv = ((tol / 4) > 500) ? 500 : tol / 4;
599 
600 	/* Link with lowest tolerance determines timer interval */
601 	if (intv < n->keepalive_intv)
602 		n->keepalive_intv = intv;
603 
604 	/* Ensure link's abort limit corresponds to current tolerance */
605 	tipc_link_set_abort_limit(l, tol / n->keepalive_intv);
606 }
607 
608 static void tipc_node_delete_from_list(struct tipc_node *node)
609 {
610 #ifdef CONFIG_TIPC_CRYPTO
611 	tipc_crypto_key_flush(node->crypto_rx);
612 #endif
613 	list_del_rcu(&node->list);
614 	hlist_del_rcu(&node->hash);
615 	tipc_node_put(node);
616 }
617 
618 static void tipc_node_delete(struct tipc_node *node)
619 {
620 	trace_tipc_node_delete(node, true, " ");
621 	tipc_node_delete_from_list(node);
622 
623 	del_timer_sync(&node->timer);
624 	tipc_node_put(node);
625 }
626 
627 void tipc_node_stop(struct net *net)
628 {
629 	struct tipc_net *tn = tipc_net(net);
630 	struct tipc_node *node, *t_node;
631 
632 	spin_lock_bh(&tn->node_list_lock);
633 	list_for_each_entry_safe(node, t_node, &tn->node_list, list)
634 		tipc_node_delete(node);
635 	spin_unlock_bh(&tn->node_list_lock);
636 }
637 
638 void tipc_node_subscribe(struct net *net, struct list_head *subscr, u32 addr)
639 {
640 	struct tipc_node *n;
641 
642 	if (in_own_node(net, addr))
643 		return;
644 
645 	n = tipc_node_find(net, addr);
646 	if (!n) {
647 		pr_warn("Node subscribe rejected, unknown node 0x%x\n", addr);
648 		return;
649 	}
650 	tipc_node_write_lock(n);
651 	list_add_tail(subscr, &n->publ_list);
652 	tipc_node_write_unlock_fast(n);
653 	tipc_node_put(n);
654 }
655 
656 void tipc_node_unsubscribe(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 unsubscribe rejected, unknown node 0x%x\n", addr);
666 		return;
667 	}
668 	tipc_node_write_lock(n);
669 	list_del_init(subscr);
670 	tipc_node_write_unlock_fast(n);
671 	tipc_node_put(n);
672 }
673 
674 int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port)
675 {
676 	struct tipc_node *node;
677 	struct tipc_sock_conn *conn;
678 	int err = 0;
679 
680 	if (in_own_node(net, dnode))
681 		return 0;
682 
683 	node = tipc_node_find(net, dnode);
684 	if (!node) {
685 		pr_warn("Connecting sock to node 0x%x failed\n", dnode);
686 		return -EHOSTUNREACH;
687 	}
688 	conn = kmalloc(sizeof(*conn), GFP_ATOMIC);
689 	if (!conn) {
690 		err = -EHOSTUNREACH;
691 		goto exit;
692 	}
693 	conn->peer_node = dnode;
694 	conn->port = port;
695 	conn->peer_port = peer_port;
696 
697 	tipc_node_write_lock(node);
698 	list_add_tail(&conn->list, &node->conn_sks);
699 	tipc_node_write_unlock(node);
700 exit:
701 	tipc_node_put(node);
702 	return err;
703 }
704 
705 void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port)
706 {
707 	struct tipc_node *node;
708 	struct tipc_sock_conn *conn, *safe;
709 
710 	if (in_own_node(net, dnode))
711 		return;
712 
713 	node = tipc_node_find(net, dnode);
714 	if (!node)
715 		return;
716 
717 	tipc_node_write_lock(node);
718 	list_for_each_entry_safe(conn, safe, &node->conn_sks, list) {
719 		if (port != conn->port)
720 			continue;
721 		list_del(&conn->list);
722 		kfree(conn);
723 	}
724 	tipc_node_write_unlock(node);
725 	tipc_node_put(node);
726 }
727 
728 static void  tipc_node_clear_links(struct tipc_node *node)
729 {
730 	int i;
731 
732 	for (i = 0; i < MAX_BEARERS; i++) {
733 		struct tipc_link_entry *le = &node->links[i];
734 
735 		if (le->link) {
736 			kfree(le->link);
737 			le->link = NULL;
738 			node->link_cnt--;
739 		}
740 	}
741 }
742 
743 /* tipc_node_cleanup - delete nodes that does not
744  * have active links for NODE_CLEANUP_AFTER time
745  */
746 static bool tipc_node_cleanup(struct tipc_node *peer)
747 {
748 	struct tipc_node *temp_node;
749 	struct tipc_net *tn = tipc_net(peer->net);
750 	bool deleted = false;
751 
752 	/* If lock held by tipc_node_stop() the node will be deleted anyway */
753 	if (!spin_trylock_bh(&tn->node_list_lock))
754 		return false;
755 
756 	tipc_node_write_lock(peer);
757 
758 	if (!node_is_up(peer) && time_after(jiffies, peer->delete_at)) {
759 		tipc_node_clear_links(peer);
760 		tipc_node_delete_from_list(peer);
761 		deleted = true;
762 	}
763 	tipc_node_write_unlock(peer);
764 
765 	if (!deleted) {
766 		spin_unlock_bh(&tn->node_list_lock);
767 		return deleted;
768 	}
769 
770 	/* Calculate cluster capabilities */
771 	tn->capabilities = TIPC_NODE_CAPABILITIES;
772 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
773 		tn->capabilities &= temp_node->capabilities;
774 	}
775 	tipc_bcast_toggle_rcast(peer->net,
776 				(tn->capabilities & TIPC_BCAST_RCAST));
777 	spin_unlock_bh(&tn->node_list_lock);
778 	return deleted;
779 }
780 
781 /* tipc_node_timeout - handle expiration of node timer
782  */
783 static void tipc_node_timeout(struct timer_list *t)
784 {
785 	struct tipc_node *n = from_timer(n, t, timer);
786 	struct tipc_link_entry *le;
787 	struct sk_buff_head xmitq;
788 	int remains = n->link_cnt;
789 	int bearer_id;
790 	int rc = 0;
791 
792 	trace_tipc_node_timeout(n, false, " ");
793 	if (!node_is_up(n) && tipc_node_cleanup(n)) {
794 		/*Removing the reference of Timer*/
795 		tipc_node_put(n);
796 		return;
797 	}
798 
799 #ifdef CONFIG_TIPC_CRYPTO
800 	/* Take any crypto key related actions first */
801 	tipc_crypto_timeout(n->crypto_rx);
802 #endif
803 	__skb_queue_head_init(&xmitq);
804 
805 	/* Initial node interval to value larger (10 seconds), then it will be
806 	 * recalculated with link lowest tolerance
807 	 */
808 	tipc_node_read_lock(n);
809 	n->keepalive_intv = 10000;
810 	tipc_node_read_unlock(n);
811 	for (bearer_id = 0; remains && (bearer_id < MAX_BEARERS); bearer_id++) {
812 		tipc_node_read_lock(n);
813 		le = &n->links[bearer_id];
814 		if (le->link) {
815 			spin_lock_bh(&le->lock);
816 			/* Link tolerance may change asynchronously: */
817 			tipc_node_calculate_timer(n, le->link);
818 			rc = tipc_link_timeout(le->link, &xmitq);
819 			spin_unlock_bh(&le->lock);
820 			remains--;
821 		}
822 		tipc_node_read_unlock(n);
823 		tipc_bearer_xmit(n->net, bearer_id, &xmitq, &le->maddr, n);
824 		if (rc & TIPC_LINK_DOWN_EVT)
825 			tipc_node_link_down(n, bearer_id, false);
826 	}
827 	mod_timer(&n->timer, jiffies + msecs_to_jiffies(n->keepalive_intv));
828 }
829 
830 /**
831  * __tipc_node_link_up - handle addition of link
832  * @n: target tipc_node
833  * @bearer_id: id of the bearer
834  * @xmitq: queue for messages to be xmited on
835  * Node lock must be held by caller
836  * Link becomes active (alone or shared) or standby, depending on its priority.
837  */
838 static void __tipc_node_link_up(struct tipc_node *n, int bearer_id,
839 				struct sk_buff_head *xmitq)
840 {
841 	int *slot0 = &n->active_links[0];
842 	int *slot1 = &n->active_links[1];
843 	struct tipc_link *ol = node_active_link(n, 0);
844 	struct tipc_link *nl = n->links[bearer_id].link;
845 
846 	if (!nl || tipc_link_is_up(nl))
847 		return;
848 
849 	tipc_link_fsm_evt(nl, LINK_ESTABLISH_EVT);
850 	if (!tipc_link_is_up(nl))
851 		return;
852 
853 	n->working_links++;
854 	n->action_flags |= TIPC_NOTIFY_LINK_UP;
855 	n->link_id = tipc_link_id(nl);
856 
857 	/* Leave room for tunnel header when returning 'mtu' to users: */
858 	n->links[bearer_id].mtu = tipc_link_mss(nl);
859 
860 	tipc_bearer_add_dest(n->net, bearer_id, n->addr);
861 	tipc_bcast_inc_bearer_dst_cnt(n->net, bearer_id);
862 
863 	pr_debug("Established link <%s> on network plane %c\n",
864 		 tipc_link_name(nl), tipc_link_plane(nl));
865 	trace_tipc_node_link_up(n, true, " ");
866 
867 	/* Ensure that a STATE message goes first */
868 	tipc_link_build_state_msg(nl, xmitq);
869 
870 	/* First link? => give it both slots */
871 	if (!ol) {
872 		*slot0 = bearer_id;
873 		*slot1 = bearer_id;
874 		tipc_node_fsm_evt(n, SELF_ESTABL_CONTACT_EVT);
875 		n->action_flags |= TIPC_NOTIFY_NODE_UP;
876 		tipc_link_set_active(nl, true);
877 		tipc_bcast_add_peer(n->net, nl, xmitq);
878 		return;
879 	}
880 
881 	/* Second link => redistribute slots */
882 	if (tipc_link_prio(nl) > tipc_link_prio(ol)) {
883 		pr_debug("Old link <%s> becomes standby\n", tipc_link_name(ol));
884 		*slot0 = bearer_id;
885 		*slot1 = bearer_id;
886 		tipc_link_set_active(nl, true);
887 		tipc_link_set_active(ol, false);
888 	} else if (tipc_link_prio(nl) == tipc_link_prio(ol)) {
889 		tipc_link_set_active(nl, true);
890 		*slot1 = bearer_id;
891 	} else {
892 		pr_debug("New link <%s> is standby\n", tipc_link_name(nl));
893 	}
894 
895 	/* Prepare synchronization with first link */
896 	tipc_link_tnl_prepare(ol, nl, SYNCH_MSG, xmitq);
897 }
898 
899 /**
900  * tipc_node_link_up - handle addition of link
901  * @n: target tipc_node
902  * @bearer_id: id of the bearer
903  * @xmitq: queue for messages to be xmited on
904  *
905  * Link becomes active (alone or shared) or standby, depending on its priority.
906  */
907 static void tipc_node_link_up(struct tipc_node *n, int bearer_id,
908 			      struct sk_buff_head *xmitq)
909 {
910 	struct tipc_media_addr *maddr;
911 
912 	tipc_node_write_lock(n);
913 	__tipc_node_link_up(n, bearer_id, xmitq);
914 	maddr = &n->links[bearer_id].maddr;
915 	tipc_bearer_xmit(n->net, bearer_id, xmitq, maddr, n);
916 	tipc_node_write_unlock(n);
917 }
918 
919 /**
920  * tipc_node_link_failover() - start failover in case "half-failover"
921  *
922  * This function is only called in a very special situation where link
923  * failover can be already started on peer node but not on this node.
924  * This can happen when e.g.::
925  *
926  *	1. Both links <1A-2A>, <1B-2B> down
927  *	2. Link endpoint 2A up, but 1A still down (e.g. due to network
928  *	disturbance, wrong session, etc.)
929  *	3. Link <1B-2B> up
930  *	4. Link endpoint 2A down (e.g. due to link tolerance timeout)
931  *	5. Node 2 starts failover onto link <1B-2B>
932  *
933  *	==> Node 1 does never start link/node failover!
934  *
935  * @n: tipc node structure
936  * @l: link peer endpoint failingover (- can be NULL)
937  * @tnl: tunnel link
938  * @xmitq: queue for messages to be xmited on tnl link later
939  */
940 static void tipc_node_link_failover(struct tipc_node *n, struct tipc_link *l,
941 				    struct tipc_link *tnl,
942 				    struct sk_buff_head *xmitq)
943 {
944 	/* Avoid to be "self-failover" that can never end */
945 	if (!tipc_link_is_up(tnl))
946 		return;
947 
948 	/* Don't rush, failure link may be in the process of resetting */
949 	if (l && !tipc_link_is_reset(l))
950 		return;
951 
952 	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
953 	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
954 
955 	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
956 	tipc_link_failover_prepare(l, tnl, xmitq);
957 
958 	if (l)
959 		tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
960 	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
961 }
962 
963 /**
964  * __tipc_node_link_down - handle loss of link
965  * @n: target tipc_node
966  * @bearer_id: id of the bearer
967  * @xmitq: queue for messages to be xmited on
968  * @maddr: output media address of the bearer
969  */
970 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
971 				  struct sk_buff_head *xmitq,
972 				  struct tipc_media_addr **maddr)
973 {
974 	struct tipc_link_entry *le = &n->links[*bearer_id];
975 	int *slot0 = &n->active_links[0];
976 	int *slot1 = &n->active_links[1];
977 	int i, highest = 0, prio;
978 	struct tipc_link *l, *_l, *tnl;
979 
980 	l = n->links[*bearer_id].link;
981 	if (!l || tipc_link_is_reset(l))
982 		return;
983 
984 	n->working_links--;
985 	n->action_flags |= TIPC_NOTIFY_LINK_DOWN;
986 	n->link_id = tipc_link_id(l);
987 
988 	tipc_bearer_remove_dest(n->net, *bearer_id, n->addr);
989 
990 	pr_debug("Lost link <%s> on network plane %c\n",
991 		 tipc_link_name(l), tipc_link_plane(l));
992 
993 	/* Select new active link if any available */
994 	*slot0 = INVALID_BEARER_ID;
995 	*slot1 = INVALID_BEARER_ID;
996 	for (i = 0; i < MAX_BEARERS; i++) {
997 		_l = n->links[i].link;
998 		if (!_l || !tipc_link_is_up(_l))
999 			continue;
1000 		if (_l == l)
1001 			continue;
1002 		prio = tipc_link_prio(_l);
1003 		if (prio < highest)
1004 			continue;
1005 		if (prio > highest) {
1006 			highest = prio;
1007 			*slot0 = i;
1008 			*slot1 = i;
1009 			continue;
1010 		}
1011 		*slot1 = i;
1012 	}
1013 
1014 	if (!node_is_up(n)) {
1015 		if (tipc_link_peer_is_down(l))
1016 			tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
1017 		tipc_node_fsm_evt(n, SELF_LOST_CONTACT_EVT);
1018 		trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down!");
1019 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1020 		tipc_link_reset(l);
1021 		tipc_link_build_reset_msg(l, xmitq);
1022 		*maddr = &n->links[*bearer_id].maddr;
1023 		node_lost_contact(n, &le->inputq);
1024 		tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
1025 		return;
1026 	}
1027 	tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
1028 
1029 	/* There is still a working link => initiate failover */
1030 	*bearer_id = n->active_links[0];
1031 	tnl = n->links[*bearer_id].link;
1032 	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
1033 	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
1034 	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
1035 	tipc_link_tnl_prepare(l, tnl, FAILOVER_MSG, xmitq);
1036 	trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down -> failover!");
1037 	tipc_link_reset(l);
1038 	tipc_link_fsm_evt(l, LINK_RESET_EVT);
1039 	tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
1040 	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
1041 	*maddr = &n->links[*bearer_id].maddr;
1042 }
1043 
1044 static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete)
1045 {
1046 	struct tipc_link_entry *le = &n->links[bearer_id];
1047 	struct tipc_media_addr *maddr = NULL;
1048 	struct tipc_link *l = le->link;
1049 	int old_bearer_id = bearer_id;
1050 	struct sk_buff_head xmitq;
1051 
1052 	if (!l)
1053 		return;
1054 
1055 	__skb_queue_head_init(&xmitq);
1056 
1057 	tipc_node_write_lock(n);
1058 	if (!tipc_link_is_establishing(l)) {
1059 		__tipc_node_link_down(n, &bearer_id, &xmitq, &maddr);
1060 	} else {
1061 		/* Defuse pending tipc_node_link_up() */
1062 		tipc_link_reset(l);
1063 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1064 	}
1065 	if (delete) {
1066 		kfree(l);
1067 		le->link = NULL;
1068 		n->link_cnt--;
1069 	}
1070 	trace_tipc_node_link_down(n, true, "node link down or deleted!");
1071 	tipc_node_write_unlock(n);
1072 	if (delete)
1073 		tipc_mon_remove_peer(n->net, n->addr, old_bearer_id);
1074 	if (!skb_queue_empty(&xmitq))
1075 		tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr, n);
1076 	tipc_sk_rcv(n->net, &le->inputq);
1077 }
1078 
1079 static bool node_is_up(struct tipc_node *n)
1080 {
1081 	return n->active_links[0] != INVALID_BEARER_ID;
1082 }
1083 
1084 bool tipc_node_is_up(struct net *net, u32 addr)
1085 {
1086 	struct tipc_node *n;
1087 	bool retval = false;
1088 
1089 	if (in_own_node(net, addr))
1090 		return true;
1091 
1092 	n = tipc_node_find(net, addr);
1093 	if (!n)
1094 		return false;
1095 	retval = node_is_up(n);
1096 	tipc_node_put(n);
1097 	return retval;
1098 }
1099 
1100 static u32 tipc_node_suggest_addr(struct net *net, u32 addr)
1101 {
1102 	struct tipc_node *n;
1103 
1104 	addr ^= tipc_net(net)->random;
1105 	while ((n = tipc_node_find(net, addr))) {
1106 		tipc_node_put(n);
1107 		addr++;
1108 	}
1109 	return addr;
1110 }
1111 
1112 /* tipc_node_try_addr(): Check if addr can be used by peer, suggest other if not
1113  * Returns suggested address if any, otherwise 0
1114  */
1115 u32 tipc_node_try_addr(struct net *net, u8 *id, u32 addr)
1116 {
1117 	struct tipc_net *tn = tipc_net(net);
1118 	struct tipc_node *n;
1119 	bool preliminary;
1120 	u32 sugg_addr;
1121 
1122 	/* Suggest new address if some other peer is using this one */
1123 	n = tipc_node_find(net, addr);
1124 	if (n) {
1125 		if (!memcmp(n->peer_id, id, NODE_ID_LEN))
1126 			addr = 0;
1127 		tipc_node_put(n);
1128 		if (!addr)
1129 			return 0;
1130 		return tipc_node_suggest_addr(net, addr);
1131 	}
1132 
1133 	/* Suggest previously used address if peer is known */
1134 	n = tipc_node_find_by_id(net, id);
1135 	if (n) {
1136 		sugg_addr = n->addr;
1137 		preliminary = n->preliminary;
1138 		tipc_node_put(n);
1139 		if (!preliminary)
1140 			return sugg_addr;
1141 	}
1142 
1143 	/* Even this node may be in conflict */
1144 	if (tn->trial_addr == addr)
1145 		return tipc_node_suggest_addr(net, addr);
1146 
1147 	return 0;
1148 }
1149 
1150 void tipc_node_check_dest(struct net *net, u32 addr,
1151 			  u8 *peer_id, struct tipc_bearer *b,
1152 			  u16 capabilities, u32 signature, u32 hash_mixes,
1153 			  struct tipc_media_addr *maddr,
1154 			  bool *respond, bool *dupl_addr)
1155 {
1156 	struct tipc_node *n;
1157 	struct tipc_link *l, *snd_l;
1158 	struct tipc_link_entry *le;
1159 	bool addr_match = false;
1160 	bool sign_match = false;
1161 	bool link_up = false;
1162 	bool accept_addr = false;
1163 	bool reset = true;
1164 	char *if_name;
1165 	unsigned long intv;
1166 	u16 session;
1167 
1168 	*dupl_addr = false;
1169 	*respond = false;
1170 
1171 	n = tipc_node_create(net, addr, peer_id, capabilities, hash_mixes,
1172 			     false);
1173 	if (!n)
1174 		return;
1175 
1176 	tipc_node_write_lock(n);
1177 	if (unlikely(!n->bc_entry.link)) {
1178 		snd_l = tipc_bc_sndlink(net);
1179 		if (!tipc_link_bc_create(net, tipc_own_addr(net),
1180 					 addr, peer_id, U16_MAX,
1181 					 tipc_link_min_win(snd_l),
1182 					 tipc_link_max_win(snd_l),
1183 					 n->capabilities,
1184 					 &n->bc_entry.inputq1,
1185 					 &n->bc_entry.namedq, snd_l,
1186 					 &n->bc_entry.link)) {
1187 			pr_warn("Broadcast rcv link creation failed, no mem\n");
1188 			tipc_node_write_unlock_fast(n);
1189 			tipc_node_put(n);
1190 			return;
1191 		}
1192 	}
1193 
1194 	le = &n->links[b->identity];
1195 
1196 	/* Prepare to validate requesting node's signature and media address */
1197 	l = le->link;
1198 	link_up = l && tipc_link_is_up(l);
1199 	addr_match = l && !memcmp(&le->maddr, maddr, sizeof(*maddr));
1200 	sign_match = (signature == n->signature);
1201 
1202 	/* These three flags give us eight permutations: */
1203 
1204 	if (sign_match && addr_match && link_up) {
1205 		/* All is fine. Do nothing. */
1206 		reset = false;
1207 		/* Peer node is not a container/local namespace */
1208 		if (!n->peer_hash_mix)
1209 			n->peer_hash_mix = hash_mixes;
1210 	} else if (sign_match && addr_match && !link_up) {
1211 		/* Respond. The link will come up in due time */
1212 		*respond = true;
1213 	} else if (sign_match && !addr_match && link_up) {
1214 		/* Peer has changed i/f address without rebooting.
1215 		 * If so, the link will reset soon, and the next
1216 		 * discovery will be accepted. So we can ignore it.
1217 		 * It may also be a cloned or malicious peer having
1218 		 * chosen the same node address and signature as an
1219 		 * existing one.
1220 		 * Ignore requests until the link goes down, if ever.
1221 		 */
1222 		*dupl_addr = true;
1223 	} else if (sign_match && !addr_match && !link_up) {
1224 		/* Peer link has changed i/f address without rebooting.
1225 		 * It may also be a cloned or malicious peer; we can't
1226 		 * distinguish between the two.
1227 		 * The signature is correct, so we must accept.
1228 		 */
1229 		accept_addr = true;
1230 		*respond = true;
1231 	} else if (!sign_match && addr_match && link_up) {
1232 		/* Peer node rebooted. Two possibilities:
1233 		 *  - Delayed re-discovery; this link endpoint has already
1234 		 *    reset and re-established contact with the peer, before
1235 		 *    receiving a discovery message from that node.
1236 		 *    (The peer happened to receive one from this node first).
1237 		 *  - The peer came back so fast that our side has not
1238 		 *    discovered it yet. Probing from this side will soon
1239 		 *    reset the link, since there can be no working link
1240 		 *    endpoint at the peer end, and the link will re-establish.
1241 		 *  Accept the signature, since it comes from a known peer.
1242 		 */
1243 		n->signature = signature;
1244 	} else if (!sign_match && addr_match && !link_up) {
1245 		/*  The peer node has rebooted.
1246 		 *  Accept signature, since it is a known peer.
1247 		 */
1248 		n->signature = signature;
1249 		*respond = true;
1250 	} else if (!sign_match && !addr_match && link_up) {
1251 		/* Peer rebooted with new address, or a new/duplicate peer.
1252 		 * Ignore until the link goes down, if ever.
1253 		 */
1254 		*dupl_addr = true;
1255 	} else if (!sign_match && !addr_match && !link_up) {
1256 		/* Peer rebooted with new address, or it is a new peer.
1257 		 * Accept signature and address.
1258 		 */
1259 		n->signature = signature;
1260 		accept_addr = true;
1261 		*respond = true;
1262 	}
1263 
1264 	if (!accept_addr)
1265 		goto exit;
1266 
1267 	/* Now create new link if not already existing */
1268 	if (!l) {
1269 		if (n->link_cnt == 2)
1270 			goto exit;
1271 
1272 		if_name = strchr(b->name, ':') + 1;
1273 		get_random_bytes(&session, sizeof(u16));
1274 		if (!tipc_link_create(net, if_name, b->identity, b->tolerance,
1275 				      b->net_plane, b->mtu, b->priority,
1276 				      b->min_win, b->max_win, session,
1277 				      tipc_own_addr(net), addr, peer_id,
1278 				      n->capabilities,
1279 				      tipc_bc_sndlink(n->net), n->bc_entry.link,
1280 				      &le->inputq,
1281 				      &n->bc_entry.namedq, &l)) {
1282 			*respond = false;
1283 			goto exit;
1284 		}
1285 		trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link created!");
1286 		tipc_link_reset(l);
1287 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1288 		if (n->state == NODE_FAILINGOVER)
1289 			tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
1290 		le->link = l;
1291 		n->link_cnt++;
1292 		tipc_node_calculate_timer(n, l);
1293 		if (n->link_cnt == 1) {
1294 			intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
1295 			if (!mod_timer(&n->timer, intv))
1296 				tipc_node_get(n);
1297 		}
1298 	}
1299 	memcpy(&le->maddr, maddr, sizeof(*maddr));
1300 exit:
1301 	tipc_node_write_unlock(n);
1302 	if (reset && l && !tipc_link_is_reset(l))
1303 		tipc_node_link_down(n, b->identity, false);
1304 	tipc_node_put(n);
1305 }
1306 
1307 void tipc_node_delete_links(struct net *net, int bearer_id)
1308 {
1309 	struct tipc_net *tn = net_generic(net, tipc_net_id);
1310 	struct tipc_node *n;
1311 
1312 	rcu_read_lock();
1313 	list_for_each_entry_rcu(n, &tn->node_list, list) {
1314 		tipc_node_link_down(n, bearer_id, true);
1315 	}
1316 	rcu_read_unlock();
1317 }
1318 
1319 static void tipc_node_reset_links(struct tipc_node *n)
1320 {
1321 	int i;
1322 
1323 	pr_warn("Resetting all links to %x\n", n->addr);
1324 
1325 	trace_tipc_node_reset_links(n, true, " ");
1326 	for (i = 0; i < MAX_BEARERS; i++) {
1327 		tipc_node_link_down(n, i, false);
1328 	}
1329 }
1330 
1331 /* tipc_node_fsm_evt - node finite state machine
1332  * Determines when contact is allowed with peer node
1333  */
1334 static void tipc_node_fsm_evt(struct tipc_node *n, int evt)
1335 {
1336 	int state = n->state;
1337 
1338 	switch (state) {
1339 	case SELF_DOWN_PEER_DOWN:
1340 		switch (evt) {
1341 		case SELF_ESTABL_CONTACT_EVT:
1342 			state = SELF_UP_PEER_COMING;
1343 			break;
1344 		case PEER_ESTABL_CONTACT_EVT:
1345 			state = SELF_COMING_PEER_UP;
1346 			break;
1347 		case SELF_LOST_CONTACT_EVT:
1348 		case PEER_LOST_CONTACT_EVT:
1349 			break;
1350 		case NODE_SYNCH_END_EVT:
1351 		case NODE_SYNCH_BEGIN_EVT:
1352 		case NODE_FAILOVER_BEGIN_EVT:
1353 		case NODE_FAILOVER_END_EVT:
1354 		default:
1355 			goto illegal_evt;
1356 		}
1357 		break;
1358 	case SELF_UP_PEER_UP:
1359 		switch (evt) {
1360 		case SELF_LOST_CONTACT_EVT:
1361 			state = SELF_DOWN_PEER_LEAVING;
1362 			break;
1363 		case PEER_LOST_CONTACT_EVT:
1364 			state = SELF_LEAVING_PEER_DOWN;
1365 			break;
1366 		case NODE_SYNCH_BEGIN_EVT:
1367 			state = NODE_SYNCHING;
1368 			break;
1369 		case NODE_FAILOVER_BEGIN_EVT:
1370 			state = NODE_FAILINGOVER;
1371 			break;
1372 		case SELF_ESTABL_CONTACT_EVT:
1373 		case PEER_ESTABL_CONTACT_EVT:
1374 		case NODE_SYNCH_END_EVT:
1375 		case NODE_FAILOVER_END_EVT:
1376 			break;
1377 		default:
1378 			goto illegal_evt;
1379 		}
1380 		break;
1381 	case SELF_DOWN_PEER_LEAVING:
1382 		switch (evt) {
1383 		case PEER_LOST_CONTACT_EVT:
1384 			state = SELF_DOWN_PEER_DOWN;
1385 			break;
1386 		case SELF_ESTABL_CONTACT_EVT:
1387 		case PEER_ESTABL_CONTACT_EVT:
1388 		case SELF_LOST_CONTACT_EVT:
1389 			break;
1390 		case NODE_SYNCH_END_EVT:
1391 		case NODE_SYNCH_BEGIN_EVT:
1392 		case NODE_FAILOVER_BEGIN_EVT:
1393 		case NODE_FAILOVER_END_EVT:
1394 		default:
1395 			goto illegal_evt;
1396 		}
1397 		break;
1398 	case SELF_UP_PEER_COMING:
1399 		switch (evt) {
1400 		case PEER_ESTABL_CONTACT_EVT:
1401 			state = SELF_UP_PEER_UP;
1402 			break;
1403 		case SELF_LOST_CONTACT_EVT:
1404 			state = SELF_DOWN_PEER_DOWN;
1405 			break;
1406 		case SELF_ESTABL_CONTACT_EVT:
1407 		case PEER_LOST_CONTACT_EVT:
1408 		case NODE_SYNCH_END_EVT:
1409 		case NODE_FAILOVER_BEGIN_EVT:
1410 			break;
1411 		case NODE_SYNCH_BEGIN_EVT:
1412 		case NODE_FAILOVER_END_EVT:
1413 		default:
1414 			goto illegal_evt;
1415 		}
1416 		break;
1417 	case SELF_COMING_PEER_UP:
1418 		switch (evt) {
1419 		case SELF_ESTABL_CONTACT_EVT:
1420 			state = SELF_UP_PEER_UP;
1421 			break;
1422 		case PEER_LOST_CONTACT_EVT:
1423 			state = SELF_DOWN_PEER_DOWN;
1424 			break;
1425 		case SELF_LOST_CONTACT_EVT:
1426 		case PEER_ESTABL_CONTACT_EVT:
1427 			break;
1428 		case NODE_SYNCH_END_EVT:
1429 		case NODE_SYNCH_BEGIN_EVT:
1430 		case NODE_FAILOVER_BEGIN_EVT:
1431 		case NODE_FAILOVER_END_EVT:
1432 		default:
1433 			goto illegal_evt;
1434 		}
1435 		break;
1436 	case SELF_LEAVING_PEER_DOWN:
1437 		switch (evt) {
1438 		case SELF_LOST_CONTACT_EVT:
1439 			state = SELF_DOWN_PEER_DOWN;
1440 			break;
1441 		case SELF_ESTABL_CONTACT_EVT:
1442 		case PEER_ESTABL_CONTACT_EVT:
1443 		case PEER_LOST_CONTACT_EVT:
1444 			break;
1445 		case NODE_SYNCH_END_EVT:
1446 		case NODE_SYNCH_BEGIN_EVT:
1447 		case NODE_FAILOVER_BEGIN_EVT:
1448 		case NODE_FAILOVER_END_EVT:
1449 		default:
1450 			goto illegal_evt;
1451 		}
1452 		break;
1453 	case NODE_FAILINGOVER:
1454 		switch (evt) {
1455 		case SELF_LOST_CONTACT_EVT:
1456 			state = SELF_DOWN_PEER_LEAVING;
1457 			break;
1458 		case PEER_LOST_CONTACT_EVT:
1459 			state = SELF_LEAVING_PEER_DOWN;
1460 			break;
1461 		case NODE_FAILOVER_END_EVT:
1462 			state = SELF_UP_PEER_UP;
1463 			break;
1464 		case NODE_FAILOVER_BEGIN_EVT:
1465 		case SELF_ESTABL_CONTACT_EVT:
1466 		case PEER_ESTABL_CONTACT_EVT:
1467 			break;
1468 		case NODE_SYNCH_BEGIN_EVT:
1469 		case NODE_SYNCH_END_EVT:
1470 		default:
1471 			goto illegal_evt;
1472 		}
1473 		break;
1474 	case NODE_SYNCHING:
1475 		switch (evt) {
1476 		case SELF_LOST_CONTACT_EVT:
1477 			state = SELF_DOWN_PEER_LEAVING;
1478 			break;
1479 		case PEER_LOST_CONTACT_EVT:
1480 			state = SELF_LEAVING_PEER_DOWN;
1481 			break;
1482 		case NODE_SYNCH_END_EVT:
1483 			state = SELF_UP_PEER_UP;
1484 			break;
1485 		case NODE_FAILOVER_BEGIN_EVT:
1486 			state = NODE_FAILINGOVER;
1487 			break;
1488 		case NODE_SYNCH_BEGIN_EVT:
1489 		case SELF_ESTABL_CONTACT_EVT:
1490 		case PEER_ESTABL_CONTACT_EVT:
1491 			break;
1492 		case NODE_FAILOVER_END_EVT:
1493 		default:
1494 			goto illegal_evt;
1495 		}
1496 		break;
1497 	default:
1498 		pr_err("Unknown node fsm state %x\n", state);
1499 		break;
1500 	}
1501 	trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
1502 	n->state = state;
1503 	return;
1504 
1505 illegal_evt:
1506 	pr_err("Illegal node fsm evt %x in state %x\n", evt, state);
1507 	trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
1508 }
1509 
1510 static void node_lost_contact(struct tipc_node *n,
1511 			      struct sk_buff_head *inputq)
1512 {
1513 	struct tipc_sock_conn *conn, *safe;
1514 	struct tipc_link *l;
1515 	struct list_head *conns = &n->conn_sks;
1516 	struct sk_buff *skb;
1517 	uint i;
1518 
1519 	pr_debug("Lost contact with %x\n", n->addr);
1520 	n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
1521 	trace_tipc_node_lost_contact(n, true, " ");
1522 
1523 	/* Clean up broadcast state */
1524 	tipc_bcast_remove_peer(n->net, n->bc_entry.link);
1525 	skb_queue_purge(&n->bc_entry.namedq);
1526 
1527 	/* Abort any ongoing link failover */
1528 	for (i = 0; i < MAX_BEARERS; i++) {
1529 		l = n->links[i].link;
1530 		if (l)
1531 			tipc_link_fsm_evt(l, LINK_FAILOVER_END_EVT);
1532 	}
1533 
1534 	/* Notify publications from this node */
1535 	n->action_flags |= TIPC_NOTIFY_NODE_DOWN;
1536 	n->peer_net = NULL;
1537 	n->peer_hash_mix = 0;
1538 	/* Notify sockets connected to node */
1539 	list_for_each_entry_safe(conn, safe, conns, list) {
1540 		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_CONN_MSG,
1541 				      SHORT_H_SIZE, 0, tipc_own_addr(n->net),
1542 				      conn->peer_node, conn->port,
1543 				      conn->peer_port, TIPC_ERR_NO_NODE);
1544 		if (likely(skb))
1545 			skb_queue_tail(inputq, skb);
1546 		list_del(&conn->list);
1547 		kfree(conn);
1548 	}
1549 }
1550 
1551 /**
1552  * tipc_node_get_linkname - get the name of a link
1553  *
1554  * @net: the applicable net namespace
1555  * @bearer_id: id of the bearer
1556  * @addr: peer node address
1557  * @linkname: link name output buffer
1558  * @len: size of @linkname output buffer
1559  *
1560  * Return: 0 on success
1561  */
1562 int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 addr,
1563 			   char *linkname, size_t len)
1564 {
1565 	struct tipc_link *link;
1566 	int err = -EINVAL;
1567 	struct tipc_node *node = tipc_node_find(net, addr);
1568 
1569 	if (!node)
1570 		return err;
1571 
1572 	if (bearer_id >= MAX_BEARERS)
1573 		goto exit;
1574 
1575 	tipc_node_read_lock(node);
1576 	link = node->links[bearer_id].link;
1577 	if (link) {
1578 		strncpy(linkname, tipc_link_name(link), len);
1579 		err = 0;
1580 	}
1581 	tipc_node_read_unlock(node);
1582 exit:
1583 	tipc_node_put(node);
1584 	return err;
1585 }
1586 
1587 /* Caller should hold node lock for the passed node */
1588 static int __tipc_nl_add_node(struct tipc_nl_msg *msg, struct tipc_node *node)
1589 {
1590 	void *hdr;
1591 	struct nlattr *attrs;
1592 
1593 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1594 			  NLM_F_MULTI, TIPC_NL_NODE_GET);
1595 	if (!hdr)
1596 		return -EMSGSIZE;
1597 
1598 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NODE);
1599 	if (!attrs)
1600 		goto msg_full;
1601 
1602 	if (nla_put_u32(msg->skb, TIPC_NLA_NODE_ADDR, node->addr))
1603 		goto attr_msg_full;
1604 	if (node_is_up(node))
1605 		if (nla_put_flag(msg->skb, TIPC_NLA_NODE_UP))
1606 			goto attr_msg_full;
1607 
1608 	nla_nest_end(msg->skb, attrs);
1609 	genlmsg_end(msg->skb, hdr);
1610 
1611 	return 0;
1612 
1613 attr_msg_full:
1614 	nla_nest_cancel(msg->skb, attrs);
1615 msg_full:
1616 	genlmsg_cancel(msg->skb, hdr);
1617 
1618 	return -EMSGSIZE;
1619 }
1620 
1621 static void tipc_lxc_xmit(struct net *peer_net, struct sk_buff_head *list)
1622 {
1623 	struct tipc_msg *hdr = buf_msg(skb_peek(list));
1624 	struct sk_buff_head inputq;
1625 
1626 	switch (msg_user(hdr)) {
1627 	case TIPC_LOW_IMPORTANCE:
1628 	case TIPC_MEDIUM_IMPORTANCE:
1629 	case TIPC_HIGH_IMPORTANCE:
1630 	case TIPC_CRITICAL_IMPORTANCE:
1631 		if (msg_connected(hdr) || msg_named(hdr) ||
1632 		    msg_direct(hdr)) {
1633 			tipc_loopback_trace(peer_net, list);
1634 			spin_lock_init(&list->lock);
1635 			tipc_sk_rcv(peer_net, list);
1636 			return;
1637 		}
1638 		if (msg_mcast(hdr)) {
1639 			tipc_loopback_trace(peer_net, list);
1640 			skb_queue_head_init(&inputq);
1641 			tipc_sk_mcast_rcv(peer_net, list, &inputq);
1642 			__skb_queue_purge(list);
1643 			skb_queue_purge(&inputq);
1644 			return;
1645 		}
1646 		return;
1647 	case MSG_FRAGMENTER:
1648 		if (tipc_msg_assemble(list)) {
1649 			tipc_loopback_trace(peer_net, list);
1650 			skb_queue_head_init(&inputq);
1651 			tipc_sk_mcast_rcv(peer_net, list, &inputq);
1652 			__skb_queue_purge(list);
1653 			skb_queue_purge(&inputq);
1654 		}
1655 		return;
1656 	case GROUP_PROTOCOL:
1657 	case CONN_MANAGER:
1658 		tipc_loopback_trace(peer_net, list);
1659 		spin_lock_init(&list->lock);
1660 		tipc_sk_rcv(peer_net, list);
1661 		return;
1662 	case LINK_PROTOCOL:
1663 	case NAME_DISTRIBUTOR:
1664 	case TUNNEL_PROTOCOL:
1665 	case BCAST_PROTOCOL:
1666 		return;
1667 	default:
1668 		return;
1669 	}
1670 }
1671 
1672 /**
1673  * tipc_node_xmit() - general link level function for message sending
1674  * @net: the applicable net namespace
1675  * @list: chain of buffers containing message
1676  * @dnode: address of destination node
1677  * @selector: a number used for deterministic link selection
1678  * Consumes the buffer chain.
1679  * Return: 0 if success, otherwise: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE,-ENOBUF
1680  */
1681 int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
1682 		   u32 dnode, int selector)
1683 {
1684 	struct tipc_link_entry *le = NULL;
1685 	struct tipc_node *n;
1686 	struct sk_buff_head xmitq;
1687 	bool node_up = false;
1688 	int bearer_id;
1689 	int rc;
1690 
1691 	if (in_own_node(net, dnode)) {
1692 		tipc_loopback_trace(net, list);
1693 		spin_lock_init(&list->lock);
1694 		tipc_sk_rcv(net, list);
1695 		return 0;
1696 	}
1697 
1698 	n = tipc_node_find(net, dnode);
1699 	if (unlikely(!n)) {
1700 		__skb_queue_purge(list);
1701 		return -EHOSTUNREACH;
1702 	}
1703 
1704 	tipc_node_read_lock(n);
1705 	node_up = node_is_up(n);
1706 	if (node_up && n->peer_net && check_net(n->peer_net)) {
1707 		/* xmit inner linux container */
1708 		tipc_lxc_xmit(n->peer_net, list);
1709 		if (likely(skb_queue_empty(list))) {
1710 			tipc_node_read_unlock(n);
1711 			tipc_node_put(n);
1712 			return 0;
1713 		}
1714 	}
1715 
1716 	bearer_id = n->active_links[selector & 1];
1717 	if (unlikely(bearer_id == INVALID_BEARER_ID)) {
1718 		tipc_node_read_unlock(n);
1719 		tipc_node_put(n);
1720 		__skb_queue_purge(list);
1721 		return -EHOSTUNREACH;
1722 	}
1723 
1724 	__skb_queue_head_init(&xmitq);
1725 	le = &n->links[bearer_id];
1726 	spin_lock_bh(&le->lock);
1727 	rc = tipc_link_xmit(le->link, list, &xmitq);
1728 	spin_unlock_bh(&le->lock);
1729 	tipc_node_read_unlock(n);
1730 
1731 	if (unlikely(rc == -ENOBUFS))
1732 		tipc_node_link_down(n, bearer_id, false);
1733 	else
1734 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
1735 
1736 	tipc_node_put(n);
1737 
1738 	return rc;
1739 }
1740 
1741 /* tipc_node_xmit_skb(): send single buffer to destination
1742  * Buffers sent via this function are generally TIPC_SYSTEM_IMPORTANCE
1743  * messages, which will not be rejected
1744  * The only exception is datagram messages rerouted after secondary
1745  * lookup, which are rare and safe to dispose of anyway.
1746  */
1747 int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode,
1748 		       u32 selector)
1749 {
1750 	struct sk_buff_head head;
1751 
1752 	__skb_queue_head_init(&head);
1753 	__skb_queue_tail(&head, skb);
1754 	tipc_node_xmit(net, &head, dnode, selector);
1755 	return 0;
1756 }
1757 
1758 /* tipc_node_distr_xmit(): send single buffer msgs to individual destinations
1759  * Note: this is only for SYSTEM_IMPORTANCE messages, which cannot be rejected
1760  */
1761 int tipc_node_distr_xmit(struct net *net, struct sk_buff_head *xmitq)
1762 {
1763 	struct sk_buff *skb;
1764 	u32 selector, dnode;
1765 
1766 	while ((skb = __skb_dequeue(xmitq))) {
1767 		selector = msg_origport(buf_msg(skb));
1768 		dnode = msg_destnode(buf_msg(skb));
1769 		tipc_node_xmit_skb(net, skb, dnode, selector);
1770 	}
1771 	return 0;
1772 }
1773 
1774 void tipc_node_broadcast(struct net *net, struct sk_buff *skb, int rc_dests)
1775 {
1776 	struct sk_buff_head xmitq;
1777 	struct sk_buff *txskb;
1778 	struct tipc_node *n;
1779 	u16 dummy;
1780 	u32 dst;
1781 
1782 	/* Use broadcast if all nodes support it */
1783 	if (!rc_dests && tipc_bcast_get_mode(net) != BCLINK_MODE_RCAST) {
1784 		__skb_queue_head_init(&xmitq);
1785 		__skb_queue_tail(&xmitq, skb);
1786 		tipc_bcast_xmit(net, &xmitq, &dummy);
1787 		return;
1788 	}
1789 
1790 	/* Otherwise use legacy replicast method */
1791 	rcu_read_lock();
1792 	list_for_each_entry_rcu(n, tipc_nodes(net), list) {
1793 		dst = n->addr;
1794 		if (in_own_node(net, dst))
1795 			continue;
1796 		if (!node_is_up(n))
1797 			continue;
1798 		txskb = pskb_copy(skb, GFP_ATOMIC);
1799 		if (!txskb)
1800 			break;
1801 		msg_set_destnode(buf_msg(txskb), dst);
1802 		tipc_node_xmit_skb(net, txskb, dst, 0);
1803 	}
1804 	rcu_read_unlock();
1805 	kfree_skb(skb);
1806 }
1807 
1808 static void tipc_node_mcast_rcv(struct tipc_node *n)
1809 {
1810 	struct tipc_bclink_entry *be = &n->bc_entry;
1811 
1812 	/* 'arrvq' is under inputq2's lock protection */
1813 	spin_lock_bh(&be->inputq2.lock);
1814 	spin_lock_bh(&be->inputq1.lock);
1815 	skb_queue_splice_tail_init(&be->inputq1, &be->arrvq);
1816 	spin_unlock_bh(&be->inputq1.lock);
1817 	spin_unlock_bh(&be->inputq2.lock);
1818 	tipc_sk_mcast_rcv(n->net, &be->arrvq, &be->inputq2);
1819 }
1820 
1821 static void tipc_node_bc_sync_rcv(struct tipc_node *n, struct tipc_msg *hdr,
1822 				  int bearer_id, struct sk_buff_head *xmitq)
1823 {
1824 	struct tipc_link *ucl;
1825 	int rc;
1826 
1827 	rc = tipc_bcast_sync_rcv(n->net, n->bc_entry.link, hdr, xmitq);
1828 
1829 	if (rc & TIPC_LINK_DOWN_EVT) {
1830 		tipc_node_reset_links(n);
1831 		return;
1832 	}
1833 
1834 	if (!(rc & TIPC_LINK_SND_STATE))
1835 		return;
1836 
1837 	/* If probe message, a STATE response will be sent anyway */
1838 	if (msg_probe(hdr))
1839 		return;
1840 
1841 	/* Produce a STATE message carrying broadcast NACK */
1842 	tipc_node_read_lock(n);
1843 	ucl = n->links[bearer_id].link;
1844 	if (ucl)
1845 		tipc_link_build_state_msg(ucl, xmitq);
1846 	tipc_node_read_unlock(n);
1847 }
1848 
1849 /**
1850  * tipc_node_bc_rcv - process TIPC broadcast packet arriving from off-node
1851  * @net: the applicable net namespace
1852  * @skb: TIPC packet
1853  * @bearer_id: id of bearer message arrived on
1854  *
1855  * Invoked with no locks held.
1856  */
1857 static void tipc_node_bc_rcv(struct net *net, struct sk_buff *skb, int bearer_id)
1858 {
1859 	int rc;
1860 	struct sk_buff_head xmitq;
1861 	struct tipc_bclink_entry *be;
1862 	struct tipc_link_entry *le;
1863 	struct tipc_msg *hdr = buf_msg(skb);
1864 	int usr = msg_user(hdr);
1865 	u32 dnode = msg_destnode(hdr);
1866 	struct tipc_node *n;
1867 
1868 	__skb_queue_head_init(&xmitq);
1869 
1870 	/* If NACK for other node, let rcv link for that node peek into it */
1871 	if ((usr == BCAST_PROTOCOL) && (dnode != tipc_own_addr(net)))
1872 		n = tipc_node_find(net, dnode);
1873 	else
1874 		n = tipc_node_find(net, msg_prevnode(hdr));
1875 	if (!n) {
1876 		kfree_skb(skb);
1877 		return;
1878 	}
1879 	be = &n->bc_entry;
1880 	le = &n->links[bearer_id];
1881 
1882 	rc = tipc_bcast_rcv(net, be->link, skb);
1883 
1884 	/* Broadcast ACKs are sent on a unicast link */
1885 	if (rc & TIPC_LINK_SND_STATE) {
1886 		tipc_node_read_lock(n);
1887 		tipc_link_build_state_msg(le->link, &xmitq);
1888 		tipc_node_read_unlock(n);
1889 	}
1890 
1891 	if (!skb_queue_empty(&xmitq))
1892 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
1893 
1894 	if (!skb_queue_empty(&be->inputq1))
1895 		tipc_node_mcast_rcv(n);
1896 
1897 	/* Handle NAME_DISTRIBUTOR messages sent from 1.7 nodes */
1898 	if (!skb_queue_empty(&n->bc_entry.namedq))
1899 		tipc_named_rcv(net, &n->bc_entry.namedq,
1900 			       &n->bc_entry.named_rcv_nxt,
1901 			       &n->bc_entry.named_open);
1902 
1903 	/* If reassembly or retransmission failure => reset all links to peer */
1904 	if (rc & TIPC_LINK_DOWN_EVT)
1905 		tipc_node_reset_links(n);
1906 
1907 	tipc_node_put(n);
1908 }
1909 
1910 /**
1911  * tipc_node_check_state - check and if necessary update node state
1912  * @n: target tipc_node
1913  * @skb: TIPC packet
1914  * @bearer_id: identity of bearer delivering the packet
1915  * @xmitq: queue for messages to be xmited on
1916  * Return: true if state and msg are ok, otherwise false
1917  */
1918 static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
1919 				  int bearer_id, struct sk_buff_head *xmitq)
1920 {
1921 	struct tipc_msg *hdr = buf_msg(skb);
1922 	int usr = msg_user(hdr);
1923 	int mtyp = msg_type(hdr);
1924 	u16 oseqno = msg_seqno(hdr);
1925 	u16 exp_pkts = msg_msgcnt(hdr);
1926 	u16 rcv_nxt, syncpt, dlv_nxt, inputq_len;
1927 	int state = n->state;
1928 	struct tipc_link *l, *tnl, *pl = NULL;
1929 	struct tipc_media_addr *maddr;
1930 	int pb_id;
1931 
1932 	if (trace_tipc_node_check_state_enabled()) {
1933 		trace_tipc_skb_dump(skb, false, "skb for node state check");
1934 		trace_tipc_node_check_state(n, true, " ");
1935 	}
1936 	l = n->links[bearer_id].link;
1937 	if (!l)
1938 		return false;
1939 	rcv_nxt = tipc_link_rcv_nxt(l);
1940 
1941 
1942 	if (likely((state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL)))
1943 		return true;
1944 
1945 	/* Find parallel link, if any */
1946 	for (pb_id = 0; pb_id < MAX_BEARERS; pb_id++) {
1947 		if ((pb_id != bearer_id) && n->links[pb_id].link) {
1948 			pl = n->links[pb_id].link;
1949 			break;
1950 		}
1951 	}
1952 
1953 	if (!tipc_link_validate_msg(l, hdr)) {
1954 		trace_tipc_skb_dump(skb, false, "PROTO invalid (2)!");
1955 		trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (2)!");
1956 		return false;
1957 	}
1958 
1959 	/* Check and update node accesibility if applicable */
1960 	if (state == SELF_UP_PEER_COMING) {
1961 		if (!tipc_link_is_up(l))
1962 			return true;
1963 		if (!msg_peer_link_is_up(hdr))
1964 			return true;
1965 		tipc_node_fsm_evt(n, PEER_ESTABL_CONTACT_EVT);
1966 	}
1967 
1968 	if (state == SELF_DOWN_PEER_LEAVING) {
1969 		if (msg_peer_node_is_up(hdr))
1970 			return false;
1971 		tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
1972 		return true;
1973 	}
1974 
1975 	if (state == SELF_LEAVING_PEER_DOWN)
1976 		return false;
1977 
1978 	/* Ignore duplicate packets */
1979 	if ((usr != LINK_PROTOCOL) && less(oseqno, rcv_nxt))
1980 		return true;
1981 
1982 	/* Initiate or update failover mode if applicable */
1983 	if ((usr == TUNNEL_PROTOCOL) && (mtyp == FAILOVER_MSG)) {
1984 		syncpt = oseqno + exp_pkts - 1;
1985 		if (pl && !tipc_link_is_reset(pl)) {
1986 			__tipc_node_link_down(n, &pb_id, xmitq, &maddr);
1987 			trace_tipc_node_link_down(n, true,
1988 						  "node link down <- failover!");
1989 			tipc_skb_queue_splice_tail_init(tipc_link_inputq(pl),
1990 							tipc_link_inputq(l));
1991 		}
1992 
1993 		/* If parallel link was already down, and this happened before
1994 		 * the tunnel link came up, node failover was never started.
1995 		 * Ensure that a FAILOVER_MSG is sent to get peer out of
1996 		 * NODE_FAILINGOVER state, also this node must accept
1997 		 * TUNNEL_MSGs from peer.
1998 		 */
1999 		if (n->state != NODE_FAILINGOVER)
2000 			tipc_node_link_failover(n, pl, l, xmitq);
2001 
2002 		/* If pkts arrive out of order, use lowest calculated syncpt */
2003 		if (less(syncpt, n->sync_point))
2004 			n->sync_point = syncpt;
2005 	}
2006 
2007 	/* Open parallel link when tunnel link reaches synch point */
2008 	if ((n->state == NODE_FAILINGOVER) && tipc_link_is_up(l)) {
2009 		if (!more(rcv_nxt, n->sync_point))
2010 			return true;
2011 		tipc_node_fsm_evt(n, NODE_FAILOVER_END_EVT);
2012 		if (pl)
2013 			tipc_link_fsm_evt(pl, LINK_FAILOVER_END_EVT);
2014 		return true;
2015 	}
2016 
2017 	/* No syncing needed if only one link */
2018 	if (!pl || !tipc_link_is_up(pl))
2019 		return true;
2020 
2021 	/* Initiate synch mode if applicable */
2022 	if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG) && (oseqno == 1)) {
2023 		if (n->capabilities & TIPC_TUNNEL_ENHANCED)
2024 			syncpt = msg_syncpt(hdr);
2025 		else
2026 			syncpt = msg_seqno(msg_inner_hdr(hdr)) + exp_pkts - 1;
2027 		if (!tipc_link_is_up(l))
2028 			__tipc_node_link_up(n, bearer_id, xmitq);
2029 		if (n->state == SELF_UP_PEER_UP) {
2030 			n->sync_point = syncpt;
2031 			tipc_link_fsm_evt(l, LINK_SYNCH_BEGIN_EVT);
2032 			tipc_node_fsm_evt(n, NODE_SYNCH_BEGIN_EVT);
2033 		}
2034 	}
2035 
2036 	/* Open tunnel link when parallel link reaches synch point */
2037 	if (n->state == NODE_SYNCHING) {
2038 		if (tipc_link_is_synching(l)) {
2039 			tnl = l;
2040 		} else {
2041 			tnl = pl;
2042 			pl = l;
2043 		}
2044 		inputq_len = skb_queue_len(tipc_link_inputq(pl));
2045 		dlv_nxt = tipc_link_rcv_nxt(pl) - inputq_len;
2046 		if (more(dlv_nxt, n->sync_point)) {
2047 			tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
2048 			tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
2049 			return true;
2050 		}
2051 		if (l == pl)
2052 			return true;
2053 		if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG))
2054 			return true;
2055 		if (usr == LINK_PROTOCOL)
2056 			return true;
2057 		return false;
2058 	}
2059 	return true;
2060 }
2061 
2062 /**
2063  * tipc_rcv - process TIPC packets/messages arriving from off-node
2064  * @net: the applicable net namespace
2065  * @skb: TIPC packet
2066  * @b: pointer to bearer message arrived on
2067  *
2068  * Invoked with no locks held. Bearer pointer must point to a valid bearer
2069  * structure (i.e. cannot be NULL), but bearer can be inactive.
2070  */
2071 void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
2072 {
2073 	struct sk_buff_head xmitq;
2074 	struct tipc_link_entry *le;
2075 	struct tipc_msg *hdr;
2076 	struct tipc_node *n;
2077 	int bearer_id = b->identity;
2078 	u32 self = tipc_own_addr(net);
2079 	int usr, rc = 0;
2080 	u16 bc_ack;
2081 #ifdef CONFIG_TIPC_CRYPTO
2082 	struct tipc_ehdr *ehdr;
2083 
2084 	/* Check if message must be decrypted first */
2085 	if (TIPC_SKB_CB(skb)->decrypted || !tipc_ehdr_validate(skb))
2086 		goto rcv;
2087 
2088 	ehdr = (struct tipc_ehdr *)skb->data;
2089 	if (likely(ehdr->user != LINK_CONFIG)) {
2090 		n = tipc_node_find(net, ntohl(ehdr->addr));
2091 		if (unlikely(!n))
2092 			goto discard;
2093 	} else {
2094 		n = tipc_node_find_by_id(net, ehdr->id);
2095 	}
2096 	tipc_crypto_rcv(net, (n) ? n->crypto_rx : NULL, &skb, b);
2097 	if (!skb)
2098 		return;
2099 
2100 rcv:
2101 #endif
2102 	/* Ensure message is well-formed before touching the header */
2103 	if (unlikely(!tipc_msg_validate(&skb)))
2104 		goto discard;
2105 	__skb_queue_head_init(&xmitq);
2106 	hdr = buf_msg(skb);
2107 	usr = msg_user(hdr);
2108 	bc_ack = msg_bcast_ack(hdr);
2109 
2110 	/* Handle arrival of discovery or broadcast packet */
2111 	if (unlikely(msg_non_seq(hdr))) {
2112 		if (unlikely(usr == LINK_CONFIG))
2113 			return tipc_disc_rcv(net, skb, b);
2114 		else
2115 			return tipc_node_bc_rcv(net, skb, bearer_id);
2116 	}
2117 
2118 	/* Discard unicast link messages destined for another node */
2119 	if (unlikely(!msg_short(hdr) && (msg_destnode(hdr) != self)))
2120 		goto discard;
2121 
2122 	/* Locate neighboring node that sent packet */
2123 	n = tipc_node_find(net, msg_prevnode(hdr));
2124 	if (unlikely(!n))
2125 		goto discard;
2126 	le = &n->links[bearer_id];
2127 
2128 	/* Ensure broadcast reception is in synch with peer's send state */
2129 	if (unlikely(usr == LINK_PROTOCOL)) {
2130 		if (unlikely(skb_linearize(skb))) {
2131 			tipc_node_put(n);
2132 			goto discard;
2133 		}
2134 		hdr = buf_msg(skb);
2135 		tipc_node_bc_sync_rcv(n, hdr, bearer_id, &xmitq);
2136 	} else if (unlikely(tipc_link_acked(n->bc_entry.link) != bc_ack)) {
2137 		tipc_bcast_ack_rcv(net, n->bc_entry.link, hdr);
2138 	}
2139 
2140 	/* Receive packet directly if conditions permit */
2141 	tipc_node_read_lock(n);
2142 	if (likely((n->state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL))) {
2143 		spin_lock_bh(&le->lock);
2144 		if (le->link) {
2145 			rc = tipc_link_rcv(le->link, skb, &xmitq);
2146 			skb = NULL;
2147 		}
2148 		spin_unlock_bh(&le->lock);
2149 	}
2150 	tipc_node_read_unlock(n);
2151 
2152 	/* Check/update node state before receiving */
2153 	if (unlikely(skb)) {
2154 		if (unlikely(skb_linearize(skb)))
2155 			goto out_node_put;
2156 		tipc_node_write_lock(n);
2157 		if (tipc_node_check_state(n, skb, bearer_id, &xmitq)) {
2158 			if (le->link) {
2159 				rc = tipc_link_rcv(le->link, skb, &xmitq);
2160 				skb = NULL;
2161 			}
2162 		}
2163 		tipc_node_write_unlock(n);
2164 	}
2165 
2166 	if (unlikely(rc & TIPC_LINK_UP_EVT))
2167 		tipc_node_link_up(n, bearer_id, &xmitq);
2168 
2169 	if (unlikely(rc & TIPC_LINK_DOWN_EVT))
2170 		tipc_node_link_down(n, bearer_id, false);
2171 
2172 	if (unlikely(!skb_queue_empty(&n->bc_entry.namedq)))
2173 		tipc_named_rcv(net, &n->bc_entry.namedq,
2174 			       &n->bc_entry.named_rcv_nxt,
2175 			       &n->bc_entry.named_open);
2176 
2177 	if (unlikely(!skb_queue_empty(&n->bc_entry.inputq1)))
2178 		tipc_node_mcast_rcv(n);
2179 
2180 	if (!skb_queue_empty(&le->inputq))
2181 		tipc_sk_rcv(net, &le->inputq);
2182 
2183 	if (!skb_queue_empty(&xmitq))
2184 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
2185 
2186 out_node_put:
2187 	tipc_node_put(n);
2188 discard:
2189 	kfree_skb(skb);
2190 }
2191 
2192 void tipc_node_apply_property(struct net *net, struct tipc_bearer *b,
2193 			      int prop)
2194 {
2195 	struct tipc_net *tn = tipc_net(net);
2196 	int bearer_id = b->identity;
2197 	struct sk_buff_head xmitq;
2198 	struct tipc_link_entry *e;
2199 	struct tipc_node *n;
2200 
2201 	__skb_queue_head_init(&xmitq);
2202 
2203 	rcu_read_lock();
2204 
2205 	list_for_each_entry_rcu(n, &tn->node_list, list) {
2206 		tipc_node_write_lock(n);
2207 		e = &n->links[bearer_id];
2208 		if (e->link) {
2209 			if (prop == TIPC_NLA_PROP_TOL)
2210 				tipc_link_set_tolerance(e->link, b->tolerance,
2211 							&xmitq);
2212 			else if (prop == TIPC_NLA_PROP_MTU)
2213 				tipc_link_set_mtu(e->link, b->mtu);
2214 
2215 			/* Update MTU for node link entry */
2216 			e->mtu = tipc_link_mss(e->link);
2217 		}
2218 
2219 		tipc_node_write_unlock(n);
2220 		tipc_bearer_xmit(net, bearer_id, &xmitq, &e->maddr, NULL);
2221 	}
2222 
2223 	rcu_read_unlock();
2224 }
2225 
2226 int tipc_nl_peer_rm(struct sk_buff *skb, struct genl_info *info)
2227 {
2228 	struct net *net = sock_net(skb->sk);
2229 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2230 	struct nlattr *attrs[TIPC_NLA_NET_MAX + 1];
2231 	struct tipc_node *peer, *temp_node;
2232 	u8 node_id[NODE_ID_LEN];
2233 	u64 *w0 = (u64 *)&node_id[0];
2234 	u64 *w1 = (u64 *)&node_id[8];
2235 	u32 addr;
2236 	int err;
2237 
2238 	/* We identify the peer by its net */
2239 	if (!info->attrs[TIPC_NLA_NET])
2240 		return -EINVAL;
2241 
2242 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_NET_MAX,
2243 					  info->attrs[TIPC_NLA_NET],
2244 					  tipc_nl_net_policy, info->extack);
2245 	if (err)
2246 		return err;
2247 
2248 	/* attrs[TIPC_NLA_NET_NODEID] and attrs[TIPC_NLA_NET_ADDR] are
2249 	 * mutually exclusive cases
2250 	 */
2251 	if (attrs[TIPC_NLA_NET_ADDR]) {
2252 		addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]);
2253 		if (!addr)
2254 			return -EINVAL;
2255 	}
2256 
2257 	if (attrs[TIPC_NLA_NET_NODEID]) {
2258 		if (!attrs[TIPC_NLA_NET_NODEID_W1])
2259 			return -EINVAL;
2260 		*w0 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID]);
2261 		*w1 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID_W1]);
2262 		addr = hash128to32(node_id);
2263 	}
2264 
2265 	if (in_own_node(net, addr))
2266 		return -ENOTSUPP;
2267 
2268 	spin_lock_bh(&tn->node_list_lock);
2269 	peer = tipc_node_find(net, addr);
2270 	if (!peer) {
2271 		spin_unlock_bh(&tn->node_list_lock);
2272 		return -ENXIO;
2273 	}
2274 
2275 	tipc_node_write_lock(peer);
2276 	if (peer->state != SELF_DOWN_PEER_DOWN &&
2277 	    peer->state != SELF_DOWN_PEER_LEAVING) {
2278 		tipc_node_write_unlock(peer);
2279 		err = -EBUSY;
2280 		goto err_out;
2281 	}
2282 
2283 	tipc_node_clear_links(peer);
2284 	tipc_node_write_unlock(peer);
2285 	tipc_node_delete(peer);
2286 
2287 	/* Calculate cluster capabilities */
2288 	tn->capabilities = TIPC_NODE_CAPABILITIES;
2289 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
2290 		tn->capabilities &= temp_node->capabilities;
2291 	}
2292 	tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
2293 	err = 0;
2294 err_out:
2295 	tipc_node_put(peer);
2296 	spin_unlock_bh(&tn->node_list_lock);
2297 
2298 	return err;
2299 }
2300 
2301 int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb)
2302 {
2303 	int err;
2304 	struct net *net = sock_net(skb->sk);
2305 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2306 	int done = cb->args[0];
2307 	int last_addr = cb->args[1];
2308 	struct tipc_node *node;
2309 	struct tipc_nl_msg msg;
2310 
2311 	if (done)
2312 		return 0;
2313 
2314 	msg.skb = skb;
2315 	msg.portid = NETLINK_CB(cb->skb).portid;
2316 	msg.seq = cb->nlh->nlmsg_seq;
2317 
2318 	rcu_read_lock();
2319 	if (last_addr) {
2320 		node = tipc_node_find(net, last_addr);
2321 		if (!node) {
2322 			rcu_read_unlock();
2323 			/* We never set seq or call nl_dump_check_consistent()
2324 			 * this means that setting prev_seq here will cause the
2325 			 * consistence check to fail in the netlink callback
2326 			 * handler. Resulting in the NLMSG_DONE message having
2327 			 * the NLM_F_DUMP_INTR flag set if the node state
2328 			 * changed while we released the lock.
2329 			 */
2330 			cb->prev_seq = 1;
2331 			return -EPIPE;
2332 		}
2333 		tipc_node_put(node);
2334 	}
2335 
2336 	list_for_each_entry_rcu(node, &tn->node_list, list) {
2337 		if (node->preliminary)
2338 			continue;
2339 		if (last_addr) {
2340 			if (node->addr == last_addr)
2341 				last_addr = 0;
2342 			else
2343 				continue;
2344 		}
2345 
2346 		tipc_node_read_lock(node);
2347 		err = __tipc_nl_add_node(&msg, node);
2348 		if (err) {
2349 			last_addr = node->addr;
2350 			tipc_node_read_unlock(node);
2351 			goto out;
2352 		}
2353 
2354 		tipc_node_read_unlock(node);
2355 	}
2356 	done = 1;
2357 out:
2358 	cb->args[0] = done;
2359 	cb->args[1] = last_addr;
2360 	rcu_read_unlock();
2361 
2362 	return skb->len;
2363 }
2364 
2365 /* tipc_node_find_by_name - locate owner node of link by link's name
2366  * @net: the applicable net namespace
2367  * @name: pointer to link name string
2368  * @bearer_id: pointer to index in 'node->links' array where the link was found.
2369  *
2370  * Returns pointer to node owning the link, or 0 if no matching link is found.
2371  */
2372 static struct tipc_node *tipc_node_find_by_name(struct net *net,
2373 						const char *link_name,
2374 						unsigned int *bearer_id)
2375 {
2376 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2377 	struct tipc_link *l;
2378 	struct tipc_node *n;
2379 	struct tipc_node *found_node = NULL;
2380 	int i;
2381 
2382 	*bearer_id = 0;
2383 	rcu_read_lock();
2384 	list_for_each_entry_rcu(n, &tn->node_list, list) {
2385 		tipc_node_read_lock(n);
2386 		for (i = 0; i < MAX_BEARERS; i++) {
2387 			l = n->links[i].link;
2388 			if (l && !strcmp(tipc_link_name(l), link_name)) {
2389 				*bearer_id = i;
2390 				found_node = n;
2391 				break;
2392 			}
2393 		}
2394 		tipc_node_read_unlock(n);
2395 		if (found_node)
2396 			break;
2397 	}
2398 	rcu_read_unlock();
2399 
2400 	return found_node;
2401 }
2402 
2403 int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info)
2404 {
2405 	int err;
2406 	int res = 0;
2407 	int bearer_id;
2408 	char *name;
2409 	struct tipc_link *link;
2410 	struct tipc_node *node;
2411 	struct sk_buff_head xmitq;
2412 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2413 	struct net *net = sock_net(skb->sk);
2414 
2415 	__skb_queue_head_init(&xmitq);
2416 
2417 	if (!info->attrs[TIPC_NLA_LINK])
2418 		return -EINVAL;
2419 
2420 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2421 					  info->attrs[TIPC_NLA_LINK],
2422 					  tipc_nl_link_policy, info->extack);
2423 	if (err)
2424 		return err;
2425 
2426 	if (!attrs[TIPC_NLA_LINK_NAME])
2427 		return -EINVAL;
2428 
2429 	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2430 
2431 	if (strcmp(name, tipc_bclink_name) == 0)
2432 		return tipc_nl_bc_link_set(net, attrs);
2433 
2434 	node = tipc_node_find_by_name(net, name, &bearer_id);
2435 	if (!node)
2436 		return -EINVAL;
2437 
2438 	tipc_node_read_lock(node);
2439 
2440 	link = node->links[bearer_id].link;
2441 	if (!link) {
2442 		res = -EINVAL;
2443 		goto out;
2444 	}
2445 
2446 	if (attrs[TIPC_NLA_LINK_PROP]) {
2447 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
2448 
2449 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP], props);
2450 		if (err) {
2451 			res = err;
2452 			goto out;
2453 		}
2454 
2455 		if (props[TIPC_NLA_PROP_TOL]) {
2456 			u32 tol;
2457 
2458 			tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2459 			tipc_link_set_tolerance(link, tol, &xmitq);
2460 		}
2461 		if (props[TIPC_NLA_PROP_PRIO]) {
2462 			u32 prio;
2463 
2464 			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2465 			tipc_link_set_prio(link, prio, &xmitq);
2466 		}
2467 		if (props[TIPC_NLA_PROP_WIN]) {
2468 			u32 max_win;
2469 
2470 			max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2471 			tipc_link_set_queue_limits(link,
2472 						   tipc_link_min_win(link),
2473 						   max_win);
2474 		}
2475 	}
2476 
2477 out:
2478 	tipc_node_read_unlock(node);
2479 	tipc_bearer_xmit(net, bearer_id, &xmitq, &node->links[bearer_id].maddr,
2480 			 NULL);
2481 	return res;
2482 }
2483 
2484 int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info)
2485 {
2486 	struct net *net = genl_info_net(info);
2487 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2488 	struct tipc_nl_msg msg;
2489 	char *name;
2490 	int err;
2491 
2492 	msg.portid = info->snd_portid;
2493 	msg.seq = info->snd_seq;
2494 
2495 	if (!info->attrs[TIPC_NLA_LINK])
2496 		return -EINVAL;
2497 
2498 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2499 					  info->attrs[TIPC_NLA_LINK],
2500 					  tipc_nl_link_policy, info->extack);
2501 	if (err)
2502 		return err;
2503 
2504 	if (!attrs[TIPC_NLA_LINK_NAME])
2505 		return -EINVAL;
2506 
2507 	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2508 
2509 	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2510 	if (!msg.skb)
2511 		return -ENOMEM;
2512 
2513 	if (strcmp(name, tipc_bclink_name) == 0) {
2514 		err = tipc_nl_add_bc_link(net, &msg, tipc_net(net)->bcl);
2515 		if (err)
2516 			goto err_free;
2517 	} else {
2518 		int bearer_id;
2519 		struct tipc_node *node;
2520 		struct tipc_link *link;
2521 
2522 		node = tipc_node_find_by_name(net, name, &bearer_id);
2523 		if (!node) {
2524 			err = -EINVAL;
2525 			goto err_free;
2526 		}
2527 
2528 		tipc_node_read_lock(node);
2529 		link = node->links[bearer_id].link;
2530 		if (!link) {
2531 			tipc_node_read_unlock(node);
2532 			err = -EINVAL;
2533 			goto err_free;
2534 		}
2535 
2536 		err = __tipc_nl_add_link(net, &msg, link, 0);
2537 		tipc_node_read_unlock(node);
2538 		if (err)
2539 			goto err_free;
2540 	}
2541 
2542 	return genlmsg_reply(msg.skb, info);
2543 
2544 err_free:
2545 	nlmsg_free(msg.skb);
2546 	return err;
2547 }
2548 
2549 int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info)
2550 {
2551 	int err;
2552 	char *link_name;
2553 	unsigned int bearer_id;
2554 	struct tipc_link *link;
2555 	struct tipc_node *node;
2556 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2557 	struct net *net = sock_net(skb->sk);
2558 	struct tipc_net *tn = tipc_net(net);
2559 	struct tipc_link_entry *le;
2560 
2561 	if (!info->attrs[TIPC_NLA_LINK])
2562 		return -EINVAL;
2563 
2564 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2565 					  info->attrs[TIPC_NLA_LINK],
2566 					  tipc_nl_link_policy, info->extack);
2567 	if (err)
2568 		return err;
2569 
2570 	if (!attrs[TIPC_NLA_LINK_NAME])
2571 		return -EINVAL;
2572 
2573 	link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2574 
2575 	err = -EINVAL;
2576 	if (!strcmp(link_name, tipc_bclink_name)) {
2577 		err = tipc_bclink_reset_stats(net, tipc_bc_sndlink(net));
2578 		if (err)
2579 			return err;
2580 		return 0;
2581 	} else if (strstr(link_name, tipc_bclink_name)) {
2582 		rcu_read_lock();
2583 		list_for_each_entry_rcu(node, &tn->node_list, list) {
2584 			tipc_node_read_lock(node);
2585 			link = node->bc_entry.link;
2586 			if (link && !strcmp(link_name, tipc_link_name(link))) {
2587 				err = tipc_bclink_reset_stats(net, link);
2588 				tipc_node_read_unlock(node);
2589 				break;
2590 			}
2591 			tipc_node_read_unlock(node);
2592 		}
2593 		rcu_read_unlock();
2594 		return err;
2595 	}
2596 
2597 	node = tipc_node_find_by_name(net, link_name, &bearer_id);
2598 	if (!node)
2599 		return -EINVAL;
2600 
2601 	le = &node->links[bearer_id];
2602 	tipc_node_read_lock(node);
2603 	spin_lock_bh(&le->lock);
2604 	link = node->links[bearer_id].link;
2605 	if (!link) {
2606 		spin_unlock_bh(&le->lock);
2607 		tipc_node_read_unlock(node);
2608 		return -EINVAL;
2609 	}
2610 	tipc_link_reset_stats(link);
2611 	spin_unlock_bh(&le->lock);
2612 	tipc_node_read_unlock(node);
2613 	return 0;
2614 }
2615 
2616 /* Caller should hold node lock  */
2617 static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
2618 				    struct tipc_node *node, u32 *prev_link,
2619 				    bool bc_link)
2620 {
2621 	u32 i;
2622 	int err;
2623 
2624 	for (i = *prev_link; i < MAX_BEARERS; i++) {
2625 		*prev_link = i;
2626 
2627 		if (!node->links[i].link)
2628 			continue;
2629 
2630 		err = __tipc_nl_add_link(net, msg,
2631 					 node->links[i].link, NLM_F_MULTI);
2632 		if (err)
2633 			return err;
2634 	}
2635 
2636 	if (bc_link) {
2637 		*prev_link = i;
2638 		err = tipc_nl_add_bc_link(net, msg, node->bc_entry.link);
2639 		if (err)
2640 			return err;
2641 	}
2642 
2643 	*prev_link = 0;
2644 
2645 	return 0;
2646 }
2647 
2648 int tipc_nl_node_dump_link(struct sk_buff *skb, struct netlink_callback *cb)
2649 {
2650 	struct net *net = sock_net(skb->sk);
2651 	struct nlattr **attrs = genl_dumpit_info(cb)->attrs;
2652 	struct nlattr *link[TIPC_NLA_LINK_MAX + 1];
2653 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2654 	struct tipc_node *node;
2655 	struct tipc_nl_msg msg;
2656 	u32 prev_node = cb->args[0];
2657 	u32 prev_link = cb->args[1];
2658 	int done = cb->args[2];
2659 	bool bc_link = cb->args[3];
2660 	int err;
2661 
2662 	if (done)
2663 		return 0;
2664 
2665 	if (!prev_node) {
2666 		/* Check if broadcast-receiver links dumping is needed */
2667 		if (attrs && attrs[TIPC_NLA_LINK]) {
2668 			err = nla_parse_nested_deprecated(link,
2669 							  TIPC_NLA_LINK_MAX,
2670 							  attrs[TIPC_NLA_LINK],
2671 							  tipc_nl_link_policy,
2672 							  NULL);
2673 			if (unlikely(err))
2674 				return err;
2675 			if (unlikely(!link[TIPC_NLA_LINK_BROADCAST]))
2676 				return -EINVAL;
2677 			bc_link = true;
2678 		}
2679 	}
2680 
2681 	msg.skb = skb;
2682 	msg.portid = NETLINK_CB(cb->skb).portid;
2683 	msg.seq = cb->nlh->nlmsg_seq;
2684 
2685 	rcu_read_lock();
2686 	if (prev_node) {
2687 		node = tipc_node_find(net, prev_node);
2688 		if (!node) {
2689 			/* We never set seq or call nl_dump_check_consistent()
2690 			 * this means that setting prev_seq here will cause the
2691 			 * consistence check to fail in the netlink callback
2692 			 * handler. Resulting in the last NLMSG_DONE message
2693 			 * having the NLM_F_DUMP_INTR flag set.
2694 			 */
2695 			cb->prev_seq = 1;
2696 			goto out;
2697 		}
2698 		tipc_node_put(node);
2699 
2700 		list_for_each_entry_continue_rcu(node, &tn->node_list,
2701 						 list) {
2702 			tipc_node_read_lock(node);
2703 			err = __tipc_nl_add_node_links(net, &msg, node,
2704 						       &prev_link, bc_link);
2705 			tipc_node_read_unlock(node);
2706 			if (err)
2707 				goto out;
2708 
2709 			prev_node = node->addr;
2710 		}
2711 	} else {
2712 		err = tipc_nl_add_bc_link(net, &msg, tn->bcl);
2713 		if (err)
2714 			goto out;
2715 
2716 		list_for_each_entry_rcu(node, &tn->node_list, list) {
2717 			tipc_node_read_lock(node);
2718 			err = __tipc_nl_add_node_links(net, &msg, node,
2719 						       &prev_link, bc_link);
2720 			tipc_node_read_unlock(node);
2721 			if (err)
2722 				goto out;
2723 
2724 			prev_node = node->addr;
2725 		}
2726 	}
2727 	done = 1;
2728 out:
2729 	rcu_read_unlock();
2730 
2731 	cb->args[0] = prev_node;
2732 	cb->args[1] = prev_link;
2733 	cb->args[2] = done;
2734 	cb->args[3] = bc_link;
2735 
2736 	return skb->len;
2737 }
2738 
2739 int tipc_nl_node_set_monitor(struct sk_buff *skb, struct genl_info *info)
2740 {
2741 	struct nlattr *attrs[TIPC_NLA_MON_MAX + 1];
2742 	struct net *net = sock_net(skb->sk);
2743 	int err;
2744 
2745 	if (!info->attrs[TIPC_NLA_MON])
2746 		return -EINVAL;
2747 
2748 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_MON_MAX,
2749 					  info->attrs[TIPC_NLA_MON],
2750 					  tipc_nl_monitor_policy,
2751 					  info->extack);
2752 	if (err)
2753 		return err;
2754 
2755 	if (attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]) {
2756 		u32 val;
2757 
2758 		val = nla_get_u32(attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]);
2759 		err = tipc_nl_monitor_set_threshold(net, val);
2760 		if (err)
2761 			return err;
2762 	}
2763 
2764 	return 0;
2765 }
2766 
2767 static int __tipc_nl_add_monitor_prop(struct net *net, struct tipc_nl_msg *msg)
2768 {
2769 	struct nlattr *attrs;
2770 	void *hdr;
2771 	u32 val;
2772 
2773 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2774 			  0, TIPC_NL_MON_GET);
2775 	if (!hdr)
2776 		return -EMSGSIZE;
2777 
2778 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_MON);
2779 	if (!attrs)
2780 		goto msg_full;
2781 
2782 	val = tipc_nl_monitor_get_threshold(net);
2783 
2784 	if (nla_put_u32(msg->skb, TIPC_NLA_MON_ACTIVATION_THRESHOLD, val))
2785 		goto attr_msg_full;
2786 
2787 	nla_nest_end(msg->skb, attrs);
2788 	genlmsg_end(msg->skb, hdr);
2789 
2790 	return 0;
2791 
2792 attr_msg_full:
2793 	nla_nest_cancel(msg->skb, attrs);
2794 msg_full:
2795 	genlmsg_cancel(msg->skb, hdr);
2796 
2797 	return -EMSGSIZE;
2798 }
2799 
2800 int tipc_nl_node_get_monitor(struct sk_buff *skb, struct genl_info *info)
2801 {
2802 	struct net *net = sock_net(skb->sk);
2803 	struct tipc_nl_msg msg;
2804 	int err;
2805 
2806 	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2807 	if (!msg.skb)
2808 		return -ENOMEM;
2809 	msg.portid = info->snd_portid;
2810 	msg.seq = info->snd_seq;
2811 
2812 	err = __tipc_nl_add_monitor_prop(net, &msg);
2813 	if (err) {
2814 		nlmsg_free(msg.skb);
2815 		return err;
2816 	}
2817 
2818 	return genlmsg_reply(msg.skb, info);
2819 }
2820 
2821 int tipc_nl_node_dump_monitor(struct sk_buff *skb, struct netlink_callback *cb)
2822 {
2823 	struct net *net = sock_net(skb->sk);
2824 	u32 prev_bearer = cb->args[0];
2825 	struct tipc_nl_msg msg;
2826 	int bearer_id;
2827 	int err;
2828 
2829 	if (prev_bearer == MAX_BEARERS)
2830 		return 0;
2831 
2832 	msg.skb = skb;
2833 	msg.portid = NETLINK_CB(cb->skb).portid;
2834 	msg.seq = cb->nlh->nlmsg_seq;
2835 
2836 	rtnl_lock();
2837 	for (bearer_id = prev_bearer; bearer_id < MAX_BEARERS; bearer_id++) {
2838 		err = __tipc_nl_add_monitor(net, &msg, bearer_id);
2839 		if (err)
2840 			break;
2841 	}
2842 	rtnl_unlock();
2843 	cb->args[0] = bearer_id;
2844 
2845 	return skb->len;
2846 }
2847 
2848 int tipc_nl_node_dump_monitor_peer(struct sk_buff *skb,
2849 				   struct netlink_callback *cb)
2850 {
2851 	struct net *net = sock_net(skb->sk);
2852 	u32 prev_node = cb->args[1];
2853 	u32 bearer_id = cb->args[2];
2854 	int done = cb->args[0];
2855 	struct tipc_nl_msg msg;
2856 	int err;
2857 
2858 	if (!prev_node) {
2859 		struct nlattr **attrs = genl_dumpit_info(cb)->attrs;
2860 		struct nlattr *mon[TIPC_NLA_MON_MAX + 1];
2861 
2862 		if (!attrs[TIPC_NLA_MON])
2863 			return -EINVAL;
2864 
2865 		err = nla_parse_nested_deprecated(mon, TIPC_NLA_MON_MAX,
2866 						  attrs[TIPC_NLA_MON],
2867 						  tipc_nl_monitor_policy,
2868 						  NULL);
2869 		if (err)
2870 			return err;
2871 
2872 		if (!mon[TIPC_NLA_MON_REF])
2873 			return -EINVAL;
2874 
2875 		bearer_id = nla_get_u32(mon[TIPC_NLA_MON_REF]);
2876 
2877 		if (bearer_id >= MAX_BEARERS)
2878 			return -EINVAL;
2879 	}
2880 
2881 	if (done)
2882 		return 0;
2883 
2884 	msg.skb = skb;
2885 	msg.portid = NETLINK_CB(cb->skb).portid;
2886 	msg.seq = cb->nlh->nlmsg_seq;
2887 
2888 	rtnl_lock();
2889 	err = tipc_nl_add_monitor_peer(net, &msg, bearer_id, &prev_node);
2890 	if (!err)
2891 		done = 1;
2892 
2893 	rtnl_unlock();
2894 	cb->args[0] = done;
2895 	cb->args[1] = prev_node;
2896 	cb->args[2] = bearer_id;
2897 
2898 	return skb->len;
2899 }
2900 
2901 #ifdef CONFIG_TIPC_CRYPTO
2902 static int tipc_nl_retrieve_key(struct nlattr **attrs,
2903 				struct tipc_aead_key **pkey)
2904 {
2905 	struct nlattr *attr = attrs[TIPC_NLA_NODE_KEY];
2906 	struct tipc_aead_key *key;
2907 
2908 	if (!attr)
2909 		return -ENODATA;
2910 
2911 	if (nla_len(attr) < sizeof(*key))
2912 		return -EINVAL;
2913 	key = (struct tipc_aead_key *)nla_data(attr);
2914 	if (key->keylen > TIPC_AEAD_KEYLEN_MAX ||
2915 	    nla_len(attr) < tipc_aead_key_size(key))
2916 		return -EINVAL;
2917 
2918 	*pkey = key;
2919 	return 0;
2920 }
2921 
2922 static int tipc_nl_retrieve_nodeid(struct nlattr **attrs, u8 **node_id)
2923 {
2924 	struct nlattr *attr = attrs[TIPC_NLA_NODE_ID];
2925 
2926 	if (!attr)
2927 		return -ENODATA;
2928 
2929 	if (nla_len(attr) < TIPC_NODEID_LEN)
2930 		return -EINVAL;
2931 
2932 	*node_id = (u8 *)nla_data(attr);
2933 	return 0;
2934 }
2935 
2936 static int tipc_nl_retrieve_rekeying(struct nlattr **attrs, u32 *intv)
2937 {
2938 	struct nlattr *attr = attrs[TIPC_NLA_NODE_REKEYING];
2939 
2940 	if (!attr)
2941 		return -ENODATA;
2942 
2943 	*intv = nla_get_u32(attr);
2944 	return 0;
2945 }
2946 
2947 static int __tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
2948 {
2949 	struct nlattr *attrs[TIPC_NLA_NODE_MAX + 1];
2950 	struct net *net = sock_net(skb->sk);
2951 	struct tipc_crypto *tx = tipc_net(net)->crypto_tx, *c = tx;
2952 	struct tipc_node *n = NULL;
2953 	struct tipc_aead_key *ukey;
2954 	bool rekeying = true, master_key = false;
2955 	u8 *id, *own_id, mode;
2956 	u32 intv = 0;
2957 	int rc = 0;
2958 
2959 	if (!info->attrs[TIPC_NLA_NODE])
2960 		return -EINVAL;
2961 
2962 	rc = nla_parse_nested(attrs, TIPC_NLA_NODE_MAX,
2963 			      info->attrs[TIPC_NLA_NODE],
2964 			      tipc_nl_node_policy, info->extack);
2965 	if (rc)
2966 		return rc;
2967 
2968 	own_id = tipc_own_id(net);
2969 	if (!own_id) {
2970 		GENL_SET_ERR_MSG(info, "not found own node identity (set id?)");
2971 		return -EPERM;
2972 	}
2973 
2974 	rc = tipc_nl_retrieve_rekeying(attrs, &intv);
2975 	if (rc == -ENODATA)
2976 		rekeying = false;
2977 
2978 	rc = tipc_nl_retrieve_key(attrs, &ukey);
2979 	if (rc == -ENODATA && rekeying)
2980 		goto rekeying;
2981 	else if (rc)
2982 		return rc;
2983 
2984 	rc = tipc_aead_key_validate(ukey, info);
2985 	if (rc)
2986 		return rc;
2987 
2988 	rc = tipc_nl_retrieve_nodeid(attrs, &id);
2989 	switch (rc) {
2990 	case -ENODATA:
2991 		mode = CLUSTER_KEY;
2992 		master_key = !!(attrs[TIPC_NLA_NODE_KEY_MASTER]);
2993 		break;
2994 	case 0:
2995 		mode = PER_NODE_KEY;
2996 		if (memcmp(id, own_id, NODE_ID_LEN)) {
2997 			n = tipc_node_find_by_id(net, id) ?:
2998 				tipc_node_create(net, 0, id, 0xffffu, 0, true);
2999 			if (unlikely(!n))
3000 				return -ENOMEM;
3001 			c = n->crypto_rx;
3002 		}
3003 		break;
3004 	default:
3005 		return rc;
3006 	}
3007 
3008 	/* Initiate the TX/RX key */
3009 	rc = tipc_crypto_key_init(c, ukey, mode, master_key);
3010 	if (n)
3011 		tipc_node_put(n);
3012 
3013 	if (unlikely(rc < 0)) {
3014 		GENL_SET_ERR_MSG(info, "unable to initiate or attach new key");
3015 		return rc;
3016 	} else if (c == tx) {
3017 		/* Distribute TX key but not master one */
3018 		if (!master_key && tipc_crypto_key_distr(tx, rc, NULL))
3019 			GENL_SET_ERR_MSG(info, "failed to replicate new key");
3020 rekeying:
3021 		/* Schedule TX rekeying if needed */
3022 		tipc_crypto_rekeying_sched(tx, rekeying, intv);
3023 	}
3024 
3025 	return 0;
3026 }
3027 
3028 int tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
3029 {
3030 	int err;
3031 
3032 	rtnl_lock();
3033 	err = __tipc_nl_node_set_key(skb, info);
3034 	rtnl_unlock();
3035 
3036 	return err;
3037 }
3038 
3039 static int __tipc_nl_node_flush_key(struct sk_buff *skb,
3040 				    struct genl_info *info)
3041 {
3042 	struct net *net = sock_net(skb->sk);
3043 	struct tipc_net *tn = tipc_net(net);
3044 	struct tipc_node *n;
3045 
3046 	tipc_crypto_key_flush(tn->crypto_tx);
3047 	rcu_read_lock();
3048 	list_for_each_entry_rcu(n, &tn->node_list, list)
3049 		tipc_crypto_key_flush(n->crypto_rx);
3050 	rcu_read_unlock();
3051 
3052 	return 0;
3053 }
3054 
3055 int tipc_nl_node_flush_key(struct sk_buff *skb, struct genl_info *info)
3056 {
3057 	int err;
3058 
3059 	rtnl_lock();
3060 	err = __tipc_nl_node_flush_key(skb, info);
3061 	rtnl_unlock();
3062 
3063 	return err;
3064 }
3065 #endif
3066 
3067 /**
3068  * tipc_node_dump - dump TIPC node data
3069  * @n: tipc node to be dumped
3070  * @more: dump more?
3071  *        - false: dump only tipc node data
3072  *        - true: dump node link data as well
3073  * @buf: returned buffer of dump data in format
3074  */
3075 int tipc_node_dump(struct tipc_node *n, bool more, char *buf)
3076 {
3077 	int i = 0;
3078 	size_t sz = (more) ? NODE_LMAX : NODE_LMIN;
3079 
3080 	if (!n) {
3081 		i += scnprintf(buf, sz, "node data: (null)\n");
3082 		return i;
3083 	}
3084 
3085 	i += scnprintf(buf, sz, "node data: %x", n->addr);
3086 	i += scnprintf(buf + i, sz - i, " %x", n->state);
3087 	i += scnprintf(buf + i, sz - i, " %d", n->active_links[0]);
3088 	i += scnprintf(buf + i, sz - i, " %d", n->active_links[1]);
3089 	i += scnprintf(buf + i, sz - i, " %x", n->action_flags);
3090 	i += scnprintf(buf + i, sz - i, " %u", n->failover_sent);
3091 	i += scnprintf(buf + i, sz - i, " %u", n->sync_point);
3092 	i += scnprintf(buf + i, sz - i, " %d", n->link_cnt);
3093 	i += scnprintf(buf + i, sz - i, " %u", n->working_links);
3094 	i += scnprintf(buf + i, sz - i, " %x", n->capabilities);
3095 	i += scnprintf(buf + i, sz - i, " %lu\n", n->keepalive_intv);
3096 
3097 	if (!more)
3098 		return i;
3099 
3100 	i += scnprintf(buf + i, sz - i, "link_entry[0]:\n");
3101 	i += scnprintf(buf + i, sz - i, " mtu: %u\n", n->links[0].mtu);
3102 	i += scnprintf(buf + i, sz - i, " media: ");
3103 	i += tipc_media_addr_printf(buf + i, sz - i, &n->links[0].maddr);
3104 	i += scnprintf(buf + i, sz - i, "\n");
3105 	i += tipc_link_dump(n->links[0].link, TIPC_DUMP_NONE, buf + i);
3106 	i += scnprintf(buf + i, sz - i, " inputq: ");
3107 	i += tipc_list_dump(&n->links[0].inputq, false, buf + i);
3108 
3109 	i += scnprintf(buf + i, sz - i, "link_entry[1]:\n");
3110 	i += scnprintf(buf + i, sz - i, " mtu: %u\n", n->links[1].mtu);
3111 	i += scnprintf(buf + i, sz - i, " media: ");
3112 	i += tipc_media_addr_printf(buf + i, sz - i, &n->links[1].maddr);
3113 	i += scnprintf(buf + i, sz - i, "\n");
3114 	i += tipc_link_dump(n->links[1].link, TIPC_DUMP_NONE, buf + i);
3115 	i += scnprintf(buf + i, sz - i, " inputq: ");
3116 	i += tipc_list_dump(&n->links[1].inputq, false, buf + i);
3117 
3118 	i += scnprintf(buf + i, sz - i, "bclink:\n ");
3119 	i += tipc_link_dump(n->bc_entry.link, TIPC_DUMP_NONE, buf + i);
3120 
3121 	return i;
3122 }
3123 
3124 void tipc_node_pre_cleanup_net(struct net *exit_net)
3125 {
3126 	struct tipc_node *n;
3127 	struct tipc_net *tn;
3128 	struct net *tmp;
3129 
3130 	rcu_read_lock();
3131 	for_each_net_rcu(tmp) {
3132 		if (tmp == exit_net)
3133 			continue;
3134 		tn = tipc_net(tmp);
3135 		if (!tn)
3136 			continue;
3137 		spin_lock_bh(&tn->node_list_lock);
3138 		list_for_each_entry_rcu(n, &tn->node_list, list) {
3139 			if (!n->peer_net)
3140 				continue;
3141 			if (n->peer_net != exit_net)
3142 				continue;
3143 			tipc_node_write_lock(n);
3144 			n->peer_net = NULL;
3145 			n->peer_hash_mix = 0;
3146 			tipc_node_write_unlock_fast(n);
3147 			break;
3148 		}
3149 		spin_unlock_bh(&tn->node_list_lock);
3150 	}
3151 	rcu_read_unlock();
3152 }
3153