xref: /openbmc/linux/net/tipc/node.c (revision 3213486f)
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 
48 #define INVALID_NODE_SIG	0x10000
49 #define NODE_CLEANUP_AFTER	300000
50 
51 /* Flags used to take different actions according to flag type
52  * TIPC_NOTIFY_NODE_DOWN: notify node is down
53  * TIPC_NOTIFY_NODE_UP: notify node is up
54  * TIPC_DISTRIBUTE_NAME: publish or withdraw link state name type
55  */
56 enum {
57 	TIPC_NOTIFY_NODE_DOWN		= (1 << 3),
58 	TIPC_NOTIFY_NODE_UP		= (1 << 4),
59 	TIPC_NOTIFY_LINK_UP		= (1 << 6),
60 	TIPC_NOTIFY_LINK_DOWN		= (1 << 7)
61 };
62 
63 struct tipc_link_entry {
64 	struct tipc_link *link;
65 	spinlock_t lock; /* per link */
66 	u32 mtu;
67 	struct sk_buff_head inputq;
68 	struct tipc_media_addr maddr;
69 };
70 
71 struct tipc_bclink_entry {
72 	struct tipc_link *link;
73 	struct sk_buff_head inputq1;
74 	struct sk_buff_head arrvq;
75 	struct sk_buff_head inputq2;
76 	struct sk_buff_head namedq;
77 };
78 
79 /**
80  * struct tipc_node - TIPC node structure
81  * @addr: network address of node
82  * @ref: reference counter to node object
83  * @lock: rwlock governing access to structure
84  * @net: the applicable net namespace
85  * @hash: links to adjacent nodes in unsorted hash chain
86  * @inputq: pointer to input queue containing messages for msg event
87  * @namedq: pointer to name table input queue with name table messages
88  * @active_links: bearer ids of active links, used as index into links[] array
89  * @links: array containing references to all links to node
90  * @action_flags: bit mask of different types of node actions
91  * @state: connectivity state vs peer node
92  * @sync_point: sequence number where synch/failover is finished
93  * @list: links to adjacent nodes in sorted list of cluster's nodes
94  * @working_links: number of working links to node (both active and standby)
95  * @link_cnt: number of links to node
96  * @capabilities: bitmap, indicating peer node's functional capabilities
97  * @signature: node instance identifier
98  * @link_id: local and remote bearer ids of changing link, if any
99  * @publ_list: list of publications
100  * @rcu: rcu struct for tipc_node
101  * @delete_at: indicates the time for deleting a down node
102  */
103 struct tipc_node {
104 	u32 addr;
105 	struct kref kref;
106 	rwlock_t lock;
107 	struct net *net;
108 	struct hlist_node hash;
109 	int active_links[2];
110 	struct tipc_link_entry links[MAX_BEARERS];
111 	struct tipc_bclink_entry bc_entry;
112 	int action_flags;
113 	struct list_head list;
114 	int state;
115 	bool failover_sent;
116 	u16 sync_point;
117 	int link_cnt;
118 	u16 working_links;
119 	u16 capabilities;
120 	u32 signature;
121 	u32 link_id;
122 	u8 peer_id[16];
123 	struct list_head publ_list;
124 	struct list_head conn_sks;
125 	unsigned long keepalive_intv;
126 	struct timer_list timer;
127 	struct rcu_head rcu;
128 	unsigned long delete_at;
129 };
130 
131 /* Node FSM states and events:
132  */
133 enum {
134 	SELF_DOWN_PEER_DOWN    = 0xdd,
135 	SELF_UP_PEER_UP        = 0xaa,
136 	SELF_DOWN_PEER_LEAVING = 0xd1,
137 	SELF_UP_PEER_COMING    = 0xac,
138 	SELF_COMING_PEER_UP    = 0xca,
139 	SELF_LEAVING_PEER_DOWN = 0x1d,
140 	NODE_FAILINGOVER       = 0xf0,
141 	NODE_SYNCHING          = 0xcc
142 };
143 
144 enum {
145 	SELF_ESTABL_CONTACT_EVT = 0xece,
146 	SELF_LOST_CONTACT_EVT   = 0x1ce,
147 	PEER_ESTABL_CONTACT_EVT = 0x9ece,
148 	PEER_LOST_CONTACT_EVT   = 0x91ce,
149 	NODE_FAILOVER_BEGIN_EVT = 0xfbe,
150 	NODE_FAILOVER_END_EVT   = 0xfee,
151 	NODE_SYNCH_BEGIN_EVT    = 0xcbe,
152 	NODE_SYNCH_END_EVT      = 0xcee
153 };
154 
155 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
156 				  struct sk_buff_head *xmitq,
157 				  struct tipc_media_addr **maddr);
158 static void tipc_node_link_down(struct tipc_node *n, int bearer_id,
159 				bool delete);
160 static void node_lost_contact(struct tipc_node *n, struct sk_buff_head *inputq);
161 static void tipc_node_delete(struct tipc_node *node);
162 static void tipc_node_timeout(struct timer_list *t);
163 static void tipc_node_fsm_evt(struct tipc_node *n, int evt);
164 static struct tipc_node *tipc_node_find(struct net *net, u32 addr);
165 static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id);
166 static void tipc_node_put(struct tipc_node *node);
167 static bool node_is_up(struct tipc_node *n);
168 static void tipc_node_delete_from_list(struct tipc_node *node);
169 
170 struct tipc_sock_conn {
171 	u32 port;
172 	u32 peer_port;
173 	u32 peer_node;
174 	struct list_head list;
175 };
176 
177 static struct tipc_link *node_active_link(struct tipc_node *n, int sel)
178 {
179 	int bearer_id = n->active_links[sel & 1];
180 
181 	if (unlikely(bearer_id == INVALID_BEARER_ID))
182 		return NULL;
183 
184 	return n->links[bearer_id].link;
185 }
186 
187 int tipc_node_get_mtu(struct net *net, u32 addr, u32 sel)
188 {
189 	struct tipc_node *n;
190 	int bearer_id;
191 	unsigned int mtu = MAX_MSG_SIZE;
192 
193 	n = tipc_node_find(net, addr);
194 	if (unlikely(!n))
195 		return mtu;
196 
197 	bearer_id = n->active_links[sel & 1];
198 	if (likely(bearer_id != INVALID_BEARER_ID))
199 		mtu = n->links[bearer_id].mtu;
200 	tipc_node_put(n);
201 	return mtu;
202 }
203 
204 bool tipc_node_get_id(struct net *net, u32 addr, u8 *id)
205 {
206 	u8 *own_id = tipc_own_id(net);
207 	struct tipc_node *n;
208 
209 	if (!own_id)
210 		return true;
211 
212 	if (addr == tipc_own_addr(net)) {
213 		memcpy(id, own_id, TIPC_NODEID_LEN);
214 		return true;
215 	}
216 	n = tipc_node_find(net, addr);
217 	if (!n)
218 		return false;
219 
220 	memcpy(id, &n->peer_id, TIPC_NODEID_LEN);
221 	tipc_node_put(n);
222 	return true;
223 }
224 
225 u16 tipc_node_get_capabilities(struct net *net, u32 addr)
226 {
227 	struct tipc_node *n;
228 	u16 caps;
229 
230 	n = tipc_node_find(net, addr);
231 	if (unlikely(!n))
232 		return TIPC_NODE_CAPABILITIES;
233 	caps = n->capabilities;
234 	tipc_node_put(n);
235 	return caps;
236 }
237 
238 static void tipc_node_kref_release(struct kref *kref)
239 {
240 	struct tipc_node *n = container_of(kref, struct tipc_node, kref);
241 
242 	kfree(n->bc_entry.link);
243 	kfree_rcu(n, rcu);
244 }
245 
246 static void tipc_node_put(struct tipc_node *node)
247 {
248 	kref_put(&node->kref, tipc_node_kref_release);
249 }
250 
251 static void tipc_node_get(struct tipc_node *node)
252 {
253 	kref_get(&node->kref);
254 }
255 
256 /*
257  * tipc_node_find - locate specified node object, if it exists
258  */
259 static struct tipc_node *tipc_node_find(struct net *net, u32 addr)
260 {
261 	struct tipc_net *tn = tipc_net(net);
262 	struct tipc_node *node;
263 	unsigned int thash = tipc_hashfn(addr);
264 
265 	rcu_read_lock();
266 	hlist_for_each_entry_rcu(node, &tn->node_htable[thash], hash) {
267 		if (node->addr != addr)
268 			continue;
269 		if (!kref_get_unless_zero(&node->kref))
270 			node = NULL;
271 		break;
272 	}
273 	rcu_read_unlock();
274 	return node;
275 }
276 
277 /* tipc_node_find_by_id - locate specified node object by its 128-bit id
278  * Note: this function is called only when a discovery request failed
279  * to find the node by its 32-bit id, and is not time critical
280  */
281 static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id)
282 {
283 	struct tipc_net *tn = tipc_net(net);
284 	struct tipc_node *n;
285 	bool found = false;
286 
287 	rcu_read_lock();
288 	list_for_each_entry_rcu(n, &tn->node_list, list) {
289 		read_lock_bh(&n->lock);
290 		if (!memcmp(id, n->peer_id, 16) &&
291 		    kref_get_unless_zero(&n->kref))
292 			found = true;
293 		read_unlock_bh(&n->lock);
294 		if (found)
295 			break;
296 	}
297 	rcu_read_unlock();
298 	return found ? n : NULL;
299 }
300 
301 static void tipc_node_read_lock(struct tipc_node *n)
302 {
303 	read_lock_bh(&n->lock);
304 }
305 
306 static void tipc_node_read_unlock(struct tipc_node *n)
307 {
308 	read_unlock_bh(&n->lock);
309 }
310 
311 static void tipc_node_write_lock(struct tipc_node *n)
312 {
313 	write_lock_bh(&n->lock);
314 }
315 
316 static void tipc_node_write_unlock_fast(struct tipc_node *n)
317 {
318 	write_unlock_bh(&n->lock);
319 }
320 
321 static void tipc_node_write_unlock(struct tipc_node *n)
322 {
323 	struct net *net = n->net;
324 	u32 addr = 0;
325 	u32 flags = n->action_flags;
326 	u32 link_id = 0;
327 	u32 bearer_id;
328 	struct list_head *publ_list;
329 
330 	if (likely(!flags)) {
331 		write_unlock_bh(&n->lock);
332 		return;
333 	}
334 
335 	addr = n->addr;
336 	link_id = n->link_id;
337 	bearer_id = link_id & 0xffff;
338 	publ_list = &n->publ_list;
339 
340 	n->action_flags &= ~(TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP |
341 			     TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP);
342 
343 	write_unlock_bh(&n->lock);
344 
345 	if (flags & TIPC_NOTIFY_NODE_DOWN)
346 		tipc_publ_notify(net, publ_list, addr);
347 
348 	if (flags & TIPC_NOTIFY_NODE_UP)
349 		tipc_named_node_up(net, addr);
350 
351 	if (flags & TIPC_NOTIFY_LINK_UP) {
352 		tipc_mon_peer_up(net, addr, bearer_id);
353 		tipc_nametbl_publish(net, TIPC_LINK_STATE, addr, addr,
354 				     TIPC_NODE_SCOPE, link_id, link_id);
355 	}
356 	if (flags & TIPC_NOTIFY_LINK_DOWN) {
357 		tipc_mon_peer_down(net, addr, bearer_id);
358 		tipc_nametbl_withdraw(net, TIPC_LINK_STATE, addr,
359 				      addr, link_id);
360 	}
361 }
362 
363 static struct tipc_node *tipc_node_create(struct net *net, u32 addr,
364 					  u8 *peer_id, u16 capabilities)
365 {
366 	struct tipc_net *tn = net_generic(net, tipc_net_id);
367 	struct tipc_node *n, *temp_node;
368 	struct tipc_link *l;
369 	int bearer_id;
370 	int i;
371 
372 	spin_lock_bh(&tn->node_list_lock);
373 	n = tipc_node_find(net, addr);
374 	if (n) {
375 		if (n->capabilities == capabilities)
376 			goto exit;
377 		/* Same node may come back with new capabilities */
378 		write_lock_bh(&n->lock);
379 		n->capabilities = capabilities;
380 		for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
381 			l = n->links[bearer_id].link;
382 			if (l)
383 				tipc_link_update_caps(l, capabilities);
384 		}
385 		write_unlock_bh(&n->lock);
386 		goto exit;
387 	}
388 	n = kzalloc(sizeof(*n), GFP_ATOMIC);
389 	if (!n) {
390 		pr_warn("Node creation failed, no memory\n");
391 		goto exit;
392 	}
393 	n->addr = addr;
394 	memcpy(&n->peer_id, peer_id, 16);
395 	n->net = net;
396 	n->capabilities = capabilities;
397 	kref_init(&n->kref);
398 	rwlock_init(&n->lock);
399 	INIT_HLIST_NODE(&n->hash);
400 	INIT_LIST_HEAD(&n->list);
401 	INIT_LIST_HEAD(&n->publ_list);
402 	INIT_LIST_HEAD(&n->conn_sks);
403 	skb_queue_head_init(&n->bc_entry.namedq);
404 	skb_queue_head_init(&n->bc_entry.inputq1);
405 	__skb_queue_head_init(&n->bc_entry.arrvq);
406 	skb_queue_head_init(&n->bc_entry.inputq2);
407 	for (i = 0; i < MAX_BEARERS; i++)
408 		spin_lock_init(&n->links[i].lock);
409 	n->state = SELF_DOWN_PEER_LEAVING;
410 	n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
411 	n->signature = INVALID_NODE_SIG;
412 	n->active_links[0] = INVALID_BEARER_ID;
413 	n->active_links[1] = INVALID_BEARER_ID;
414 	if (!tipc_link_bc_create(net, tipc_own_addr(net),
415 				 addr, U16_MAX,
416 				 tipc_link_window(tipc_bc_sndlink(net)),
417 				 n->capabilities,
418 				 &n->bc_entry.inputq1,
419 				 &n->bc_entry.namedq,
420 				 tipc_bc_sndlink(net),
421 				 &n->bc_entry.link)) {
422 		pr_warn("Broadcast rcv link creation failed, no memory\n");
423 		kfree(n);
424 		n = NULL;
425 		goto exit;
426 	}
427 	tipc_node_get(n);
428 	timer_setup(&n->timer, tipc_node_timeout, 0);
429 	n->keepalive_intv = U32_MAX;
430 	hlist_add_head_rcu(&n->hash, &tn->node_htable[tipc_hashfn(addr)]);
431 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
432 		if (n->addr < temp_node->addr)
433 			break;
434 	}
435 	list_add_tail_rcu(&n->list, &temp_node->list);
436 	trace_tipc_node_create(n, true, " ");
437 exit:
438 	spin_unlock_bh(&tn->node_list_lock);
439 	return n;
440 }
441 
442 static void tipc_node_calculate_timer(struct tipc_node *n, struct tipc_link *l)
443 {
444 	unsigned long tol = tipc_link_tolerance(l);
445 	unsigned long intv = ((tol / 4) > 500) ? 500 : tol / 4;
446 
447 	/* Link with lowest tolerance determines timer interval */
448 	if (intv < n->keepalive_intv)
449 		n->keepalive_intv = intv;
450 
451 	/* Ensure link's abort limit corresponds to current tolerance */
452 	tipc_link_set_abort_limit(l, tol / n->keepalive_intv);
453 }
454 
455 static void tipc_node_delete_from_list(struct tipc_node *node)
456 {
457 	list_del_rcu(&node->list);
458 	hlist_del_rcu(&node->hash);
459 	tipc_node_put(node);
460 }
461 
462 static void tipc_node_delete(struct tipc_node *node)
463 {
464 	trace_tipc_node_delete(node, true, " ");
465 	tipc_node_delete_from_list(node);
466 
467 	del_timer_sync(&node->timer);
468 	tipc_node_put(node);
469 }
470 
471 void tipc_node_stop(struct net *net)
472 {
473 	struct tipc_net *tn = tipc_net(net);
474 	struct tipc_node *node, *t_node;
475 
476 	spin_lock_bh(&tn->node_list_lock);
477 	list_for_each_entry_safe(node, t_node, &tn->node_list, list)
478 		tipc_node_delete(node);
479 	spin_unlock_bh(&tn->node_list_lock);
480 }
481 
482 void tipc_node_subscribe(struct net *net, struct list_head *subscr, u32 addr)
483 {
484 	struct tipc_node *n;
485 
486 	if (in_own_node(net, addr))
487 		return;
488 
489 	n = tipc_node_find(net, addr);
490 	if (!n) {
491 		pr_warn("Node subscribe rejected, unknown node 0x%x\n", addr);
492 		return;
493 	}
494 	tipc_node_write_lock(n);
495 	list_add_tail(subscr, &n->publ_list);
496 	tipc_node_write_unlock_fast(n);
497 	tipc_node_put(n);
498 }
499 
500 void tipc_node_unsubscribe(struct net *net, struct list_head *subscr, u32 addr)
501 {
502 	struct tipc_node *n;
503 
504 	if (in_own_node(net, addr))
505 		return;
506 
507 	n = tipc_node_find(net, addr);
508 	if (!n) {
509 		pr_warn("Node unsubscribe rejected, unknown node 0x%x\n", addr);
510 		return;
511 	}
512 	tipc_node_write_lock(n);
513 	list_del_init(subscr);
514 	tipc_node_write_unlock_fast(n);
515 	tipc_node_put(n);
516 }
517 
518 int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port)
519 {
520 	struct tipc_node *node;
521 	struct tipc_sock_conn *conn;
522 	int err = 0;
523 
524 	if (in_own_node(net, dnode))
525 		return 0;
526 
527 	node = tipc_node_find(net, dnode);
528 	if (!node) {
529 		pr_warn("Connecting sock to node 0x%x failed\n", dnode);
530 		return -EHOSTUNREACH;
531 	}
532 	conn = kmalloc(sizeof(*conn), GFP_ATOMIC);
533 	if (!conn) {
534 		err = -EHOSTUNREACH;
535 		goto exit;
536 	}
537 	conn->peer_node = dnode;
538 	conn->port = port;
539 	conn->peer_port = peer_port;
540 
541 	tipc_node_write_lock(node);
542 	list_add_tail(&conn->list, &node->conn_sks);
543 	tipc_node_write_unlock(node);
544 exit:
545 	tipc_node_put(node);
546 	return err;
547 }
548 
549 void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port)
550 {
551 	struct tipc_node *node;
552 	struct tipc_sock_conn *conn, *safe;
553 
554 	if (in_own_node(net, dnode))
555 		return;
556 
557 	node = tipc_node_find(net, dnode);
558 	if (!node)
559 		return;
560 
561 	tipc_node_write_lock(node);
562 	list_for_each_entry_safe(conn, safe, &node->conn_sks, list) {
563 		if (port != conn->port)
564 			continue;
565 		list_del(&conn->list);
566 		kfree(conn);
567 	}
568 	tipc_node_write_unlock(node);
569 	tipc_node_put(node);
570 }
571 
572 static void  tipc_node_clear_links(struct tipc_node *node)
573 {
574 	int i;
575 
576 	for (i = 0; i < MAX_BEARERS; i++) {
577 		struct tipc_link_entry *le = &node->links[i];
578 
579 		if (le->link) {
580 			kfree(le->link);
581 			le->link = NULL;
582 			node->link_cnt--;
583 		}
584 	}
585 }
586 
587 /* tipc_node_cleanup - delete nodes that does not
588  * have active links for NODE_CLEANUP_AFTER time
589  */
590 static bool tipc_node_cleanup(struct tipc_node *peer)
591 {
592 	struct tipc_net *tn = tipc_net(peer->net);
593 	bool deleted = false;
594 
595 	/* If lock held by tipc_node_stop() the node will be deleted anyway */
596 	if (!spin_trylock_bh(&tn->node_list_lock))
597 		return false;
598 
599 	tipc_node_write_lock(peer);
600 
601 	if (!node_is_up(peer) && time_after(jiffies, peer->delete_at)) {
602 		tipc_node_clear_links(peer);
603 		tipc_node_delete_from_list(peer);
604 		deleted = true;
605 	}
606 	tipc_node_write_unlock(peer);
607 	spin_unlock_bh(&tn->node_list_lock);
608 	return deleted;
609 }
610 
611 /* tipc_node_timeout - handle expiration of node timer
612  */
613 static void tipc_node_timeout(struct timer_list *t)
614 {
615 	struct tipc_node *n = from_timer(n, t, timer);
616 	struct tipc_link_entry *le;
617 	struct sk_buff_head xmitq;
618 	int remains = n->link_cnt;
619 	int bearer_id;
620 	int rc = 0;
621 
622 	trace_tipc_node_timeout(n, false, " ");
623 	if (!node_is_up(n) && tipc_node_cleanup(n)) {
624 		/*Removing the reference of Timer*/
625 		tipc_node_put(n);
626 		return;
627 	}
628 
629 	__skb_queue_head_init(&xmitq);
630 
631 	/* Initial node interval to value larger (10 seconds), then it will be
632 	 * recalculated with link lowest tolerance
633 	 */
634 	tipc_node_read_lock(n);
635 	n->keepalive_intv = 10000;
636 	tipc_node_read_unlock(n);
637 	for (bearer_id = 0; remains && (bearer_id < MAX_BEARERS); bearer_id++) {
638 		tipc_node_read_lock(n);
639 		le = &n->links[bearer_id];
640 		if (le->link) {
641 			spin_lock_bh(&le->lock);
642 			/* Link tolerance may change asynchronously: */
643 			tipc_node_calculate_timer(n, le->link);
644 			rc = tipc_link_timeout(le->link, &xmitq);
645 			spin_unlock_bh(&le->lock);
646 			remains--;
647 		}
648 		tipc_node_read_unlock(n);
649 		tipc_bearer_xmit(n->net, bearer_id, &xmitq, &le->maddr);
650 		if (rc & TIPC_LINK_DOWN_EVT)
651 			tipc_node_link_down(n, bearer_id, false);
652 	}
653 	mod_timer(&n->timer, jiffies + msecs_to_jiffies(n->keepalive_intv));
654 }
655 
656 /**
657  * __tipc_node_link_up - handle addition of link
658  * Node lock must be held by caller
659  * Link becomes active (alone or shared) or standby, depending on its priority.
660  */
661 static void __tipc_node_link_up(struct tipc_node *n, int bearer_id,
662 				struct sk_buff_head *xmitq)
663 {
664 	int *slot0 = &n->active_links[0];
665 	int *slot1 = &n->active_links[1];
666 	struct tipc_link *ol = node_active_link(n, 0);
667 	struct tipc_link *nl = n->links[bearer_id].link;
668 
669 	if (!nl || tipc_link_is_up(nl))
670 		return;
671 
672 	tipc_link_fsm_evt(nl, LINK_ESTABLISH_EVT);
673 	if (!tipc_link_is_up(nl))
674 		return;
675 
676 	n->working_links++;
677 	n->action_flags |= TIPC_NOTIFY_LINK_UP;
678 	n->link_id = tipc_link_id(nl);
679 
680 	/* Leave room for tunnel header when returning 'mtu' to users: */
681 	n->links[bearer_id].mtu = tipc_link_mtu(nl) - INT_H_SIZE;
682 
683 	tipc_bearer_add_dest(n->net, bearer_id, n->addr);
684 	tipc_bcast_inc_bearer_dst_cnt(n->net, bearer_id);
685 
686 	pr_debug("Established link <%s> on network plane %c\n",
687 		 tipc_link_name(nl), tipc_link_plane(nl));
688 	trace_tipc_node_link_up(n, true, " ");
689 
690 	/* Ensure that a STATE message goes first */
691 	tipc_link_build_state_msg(nl, xmitq);
692 
693 	/* First link? => give it both slots */
694 	if (!ol) {
695 		*slot0 = bearer_id;
696 		*slot1 = bearer_id;
697 		tipc_node_fsm_evt(n, SELF_ESTABL_CONTACT_EVT);
698 		n->failover_sent = false;
699 		n->action_flags |= TIPC_NOTIFY_NODE_UP;
700 		tipc_link_set_active(nl, true);
701 		tipc_bcast_add_peer(n->net, nl, xmitq);
702 		return;
703 	}
704 
705 	/* Second link => redistribute slots */
706 	if (tipc_link_prio(nl) > tipc_link_prio(ol)) {
707 		pr_debug("Old link <%s> becomes standby\n", tipc_link_name(ol));
708 		*slot0 = bearer_id;
709 		*slot1 = bearer_id;
710 		tipc_link_set_active(nl, true);
711 		tipc_link_set_active(ol, false);
712 	} else if (tipc_link_prio(nl) == tipc_link_prio(ol)) {
713 		tipc_link_set_active(nl, true);
714 		*slot1 = bearer_id;
715 	} else {
716 		pr_debug("New link <%s> is standby\n", tipc_link_name(nl));
717 	}
718 
719 	/* Prepare synchronization with first link */
720 	tipc_link_tnl_prepare(ol, nl, SYNCH_MSG, xmitq);
721 }
722 
723 /**
724  * tipc_node_link_up - handle addition of link
725  *
726  * Link becomes active (alone or shared) or standby, depending on its priority.
727  */
728 static void tipc_node_link_up(struct tipc_node *n, int bearer_id,
729 			      struct sk_buff_head *xmitq)
730 {
731 	struct tipc_media_addr *maddr;
732 
733 	tipc_node_write_lock(n);
734 	__tipc_node_link_up(n, bearer_id, xmitq);
735 	maddr = &n->links[bearer_id].maddr;
736 	tipc_bearer_xmit(n->net, bearer_id, xmitq, maddr);
737 	tipc_node_write_unlock(n);
738 }
739 
740 /**
741  * __tipc_node_link_down - handle loss of link
742  */
743 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
744 				  struct sk_buff_head *xmitq,
745 				  struct tipc_media_addr **maddr)
746 {
747 	struct tipc_link_entry *le = &n->links[*bearer_id];
748 	int *slot0 = &n->active_links[0];
749 	int *slot1 = &n->active_links[1];
750 	int i, highest = 0, prio;
751 	struct tipc_link *l, *_l, *tnl;
752 
753 	l = n->links[*bearer_id].link;
754 	if (!l || tipc_link_is_reset(l))
755 		return;
756 
757 	n->working_links--;
758 	n->action_flags |= TIPC_NOTIFY_LINK_DOWN;
759 	n->link_id = tipc_link_id(l);
760 
761 	tipc_bearer_remove_dest(n->net, *bearer_id, n->addr);
762 
763 	pr_debug("Lost link <%s> on network plane %c\n",
764 		 tipc_link_name(l), tipc_link_plane(l));
765 
766 	/* Select new active link if any available */
767 	*slot0 = INVALID_BEARER_ID;
768 	*slot1 = INVALID_BEARER_ID;
769 	for (i = 0; i < MAX_BEARERS; i++) {
770 		_l = n->links[i].link;
771 		if (!_l || !tipc_link_is_up(_l))
772 			continue;
773 		if (_l == l)
774 			continue;
775 		prio = tipc_link_prio(_l);
776 		if (prio < highest)
777 			continue;
778 		if (prio > highest) {
779 			highest = prio;
780 			*slot0 = i;
781 			*slot1 = i;
782 			continue;
783 		}
784 		*slot1 = i;
785 	}
786 
787 	if (!node_is_up(n)) {
788 		if (tipc_link_peer_is_down(l))
789 			tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
790 		tipc_node_fsm_evt(n, SELF_LOST_CONTACT_EVT);
791 		trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down!");
792 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
793 		tipc_link_reset(l);
794 		tipc_link_build_reset_msg(l, xmitq);
795 		*maddr = &n->links[*bearer_id].maddr;
796 		node_lost_contact(n, &le->inputq);
797 		tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
798 		return;
799 	}
800 	tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
801 
802 	/* There is still a working link => initiate failover */
803 	*bearer_id = n->active_links[0];
804 	tnl = n->links[*bearer_id].link;
805 	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
806 	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
807 	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
808 	tipc_link_tnl_prepare(l, tnl, FAILOVER_MSG, xmitq);
809 	trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down -> failover!");
810 	tipc_link_reset(l);
811 	tipc_link_fsm_evt(l, LINK_RESET_EVT);
812 	tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
813 	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
814 	*maddr = &n->links[*bearer_id].maddr;
815 }
816 
817 static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete)
818 {
819 	struct tipc_link_entry *le = &n->links[bearer_id];
820 	struct tipc_media_addr *maddr = NULL;
821 	struct tipc_link *l = le->link;
822 	int old_bearer_id = bearer_id;
823 	struct sk_buff_head xmitq;
824 
825 	if (!l)
826 		return;
827 
828 	__skb_queue_head_init(&xmitq);
829 
830 	tipc_node_write_lock(n);
831 	if (!tipc_link_is_establishing(l)) {
832 		__tipc_node_link_down(n, &bearer_id, &xmitq, &maddr);
833 	} else {
834 		/* Defuse pending tipc_node_link_up() */
835 		tipc_link_reset(l);
836 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
837 	}
838 	if (delete) {
839 		kfree(l);
840 		le->link = NULL;
841 		n->link_cnt--;
842 	}
843 	trace_tipc_node_link_down(n, true, "node link down or deleted!");
844 	tipc_node_write_unlock(n);
845 	if (delete)
846 		tipc_mon_remove_peer(n->net, n->addr, old_bearer_id);
847 	if (!skb_queue_empty(&xmitq))
848 		tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr);
849 	tipc_sk_rcv(n->net, &le->inputq);
850 }
851 
852 static bool node_is_up(struct tipc_node *n)
853 {
854 	return n->active_links[0] != INVALID_BEARER_ID;
855 }
856 
857 bool tipc_node_is_up(struct net *net, u32 addr)
858 {
859 	struct tipc_node *n;
860 	bool retval = false;
861 
862 	if (in_own_node(net, addr))
863 		return true;
864 
865 	n = tipc_node_find(net, addr);
866 	if (!n)
867 		return false;
868 	retval = node_is_up(n);
869 	tipc_node_put(n);
870 	return retval;
871 }
872 
873 static u32 tipc_node_suggest_addr(struct net *net, u32 addr)
874 {
875 	struct tipc_node *n;
876 
877 	addr ^= tipc_net(net)->random;
878 	while ((n = tipc_node_find(net, addr))) {
879 		tipc_node_put(n);
880 		addr++;
881 	}
882 	return addr;
883 }
884 
885 /* tipc_node_try_addr(): Check if addr can be used by peer, suggest other if not
886  * Returns suggested address if any, otherwise 0
887  */
888 u32 tipc_node_try_addr(struct net *net, u8 *id, u32 addr)
889 {
890 	struct tipc_net *tn = tipc_net(net);
891 	struct tipc_node *n;
892 
893 	/* Suggest new address if some other peer is using this one */
894 	n = tipc_node_find(net, addr);
895 	if (n) {
896 		if (!memcmp(n->peer_id, id, NODE_ID_LEN))
897 			addr = 0;
898 		tipc_node_put(n);
899 		if (!addr)
900 			return 0;
901 		return tipc_node_suggest_addr(net, addr);
902 	}
903 
904 	/* Suggest previously used address if peer is known */
905 	n = tipc_node_find_by_id(net, id);
906 	if (n) {
907 		addr = n->addr;
908 		tipc_node_put(n);
909 		return addr;
910 	}
911 
912 	/* Even this node may be in conflict */
913 	if (tn->trial_addr == addr)
914 		return tipc_node_suggest_addr(net, addr);
915 
916 	return 0;
917 }
918 
919 void tipc_node_check_dest(struct net *net, u32 addr,
920 			  u8 *peer_id, struct tipc_bearer *b,
921 			  u16 capabilities, u32 signature,
922 			  struct tipc_media_addr *maddr,
923 			  bool *respond, bool *dupl_addr)
924 {
925 	struct tipc_node *n;
926 	struct tipc_link *l;
927 	struct tipc_link_entry *le;
928 	bool addr_match = false;
929 	bool sign_match = false;
930 	bool link_up = false;
931 	bool accept_addr = false;
932 	bool reset = true;
933 	char *if_name;
934 	unsigned long intv;
935 	u16 session;
936 
937 	*dupl_addr = false;
938 	*respond = false;
939 
940 	n = tipc_node_create(net, addr, peer_id, capabilities);
941 	if (!n)
942 		return;
943 
944 	tipc_node_write_lock(n);
945 
946 	le = &n->links[b->identity];
947 
948 	/* Prepare to validate requesting node's signature and media address */
949 	l = le->link;
950 	link_up = l && tipc_link_is_up(l);
951 	addr_match = l && !memcmp(&le->maddr, maddr, sizeof(*maddr));
952 	sign_match = (signature == n->signature);
953 
954 	/* These three flags give us eight permutations: */
955 
956 	if (sign_match && addr_match && link_up) {
957 		/* All is fine. Do nothing. */
958 		reset = false;
959 	} else if (sign_match && addr_match && !link_up) {
960 		/* Respond. The link will come up in due time */
961 		*respond = true;
962 	} else if (sign_match && !addr_match && link_up) {
963 		/* Peer has changed i/f address without rebooting.
964 		 * If so, the link will reset soon, and the next
965 		 * discovery will be accepted. So we can ignore it.
966 		 * It may also be an cloned or malicious peer having
967 		 * chosen the same node address and signature as an
968 		 * existing one.
969 		 * Ignore requests until the link goes down, if ever.
970 		 */
971 		*dupl_addr = true;
972 	} else if (sign_match && !addr_match && !link_up) {
973 		/* Peer link has changed i/f address without rebooting.
974 		 * It may also be a cloned or malicious peer; we can't
975 		 * distinguish between the two.
976 		 * The signature is correct, so we must accept.
977 		 */
978 		accept_addr = true;
979 		*respond = true;
980 	} else if (!sign_match && addr_match && link_up) {
981 		/* Peer node rebooted. Two possibilities:
982 		 *  - Delayed re-discovery; this link endpoint has already
983 		 *    reset and re-established contact with the peer, before
984 		 *    receiving a discovery message from that node.
985 		 *    (The peer happened to receive one from this node first).
986 		 *  - The peer came back so fast that our side has not
987 		 *    discovered it yet. Probing from this side will soon
988 		 *    reset the link, since there can be no working link
989 		 *    endpoint at the peer end, and the link will re-establish.
990 		 *  Accept the signature, since it comes from a known peer.
991 		 */
992 		n->signature = signature;
993 	} else if (!sign_match && addr_match && !link_up) {
994 		/*  The peer node has rebooted.
995 		 *  Accept signature, since it is a known peer.
996 		 */
997 		n->signature = signature;
998 		*respond = true;
999 	} else if (!sign_match && !addr_match && link_up) {
1000 		/* Peer rebooted with new address, or a new/duplicate peer.
1001 		 * Ignore until the link goes down, if ever.
1002 		 */
1003 		*dupl_addr = true;
1004 	} else if (!sign_match && !addr_match && !link_up) {
1005 		/* Peer rebooted with new address, or it is a new peer.
1006 		 * Accept signature and address.
1007 		 */
1008 		n->signature = signature;
1009 		accept_addr = true;
1010 		*respond = true;
1011 	}
1012 
1013 	if (!accept_addr)
1014 		goto exit;
1015 
1016 	/* Now create new link if not already existing */
1017 	if (!l) {
1018 		if (n->link_cnt == 2)
1019 			goto exit;
1020 
1021 		if_name = strchr(b->name, ':') + 1;
1022 		get_random_bytes(&session, sizeof(u16));
1023 		if (!tipc_link_create(net, if_name, b->identity, b->tolerance,
1024 				      b->net_plane, b->mtu, b->priority,
1025 				      b->window, session,
1026 				      tipc_own_addr(net), addr, peer_id,
1027 				      n->capabilities,
1028 				      tipc_bc_sndlink(n->net), n->bc_entry.link,
1029 				      &le->inputq,
1030 				      &n->bc_entry.namedq, &l)) {
1031 			*respond = false;
1032 			goto exit;
1033 		}
1034 		trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link created!");
1035 		tipc_link_reset(l);
1036 		tipc_link_fsm_evt(l, LINK_RESET_EVT);
1037 		if (n->state == NODE_FAILINGOVER)
1038 			tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
1039 		le->link = l;
1040 		n->link_cnt++;
1041 		tipc_node_calculate_timer(n, l);
1042 		if (n->link_cnt == 1) {
1043 			intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
1044 			if (!mod_timer(&n->timer, intv))
1045 				tipc_node_get(n);
1046 		}
1047 	}
1048 	memcpy(&le->maddr, maddr, sizeof(*maddr));
1049 exit:
1050 	tipc_node_write_unlock(n);
1051 	if (reset && l && !tipc_link_is_reset(l))
1052 		tipc_node_link_down(n, b->identity, false);
1053 	tipc_node_put(n);
1054 }
1055 
1056 void tipc_node_delete_links(struct net *net, int bearer_id)
1057 {
1058 	struct tipc_net *tn = net_generic(net, tipc_net_id);
1059 	struct tipc_node *n;
1060 
1061 	rcu_read_lock();
1062 	list_for_each_entry_rcu(n, &tn->node_list, list) {
1063 		tipc_node_link_down(n, bearer_id, true);
1064 	}
1065 	rcu_read_unlock();
1066 }
1067 
1068 static void tipc_node_reset_links(struct tipc_node *n)
1069 {
1070 	int i;
1071 
1072 	pr_warn("Resetting all links to %x\n", n->addr);
1073 
1074 	trace_tipc_node_reset_links(n, true, " ");
1075 	for (i = 0; i < MAX_BEARERS; i++) {
1076 		tipc_node_link_down(n, i, false);
1077 	}
1078 }
1079 
1080 /* tipc_node_fsm_evt - node finite state machine
1081  * Determines when contact is allowed with peer node
1082  */
1083 static void tipc_node_fsm_evt(struct tipc_node *n, int evt)
1084 {
1085 	int state = n->state;
1086 
1087 	switch (state) {
1088 	case SELF_DOWN_PEER_DOWN:
1089 		switch (evt) {
1090 		case SELF_ESTABL_CONTACT_EVT:
1091 			state = SELF_UP_PEER_COMING;
1092 			break;
1093 		case PEER_ESTABL_CONTACT_EVT:
1094 			state = SELF_COMING_PEER_UP;
1095 			break;
1096 		case SELF_LOST_CONTACT_EVT:
1097 		case PEER_LOST_CONTACT_EVT:
1098 			break;
1099 		case NODE_SYNCH_END_EVT:
1100 		case NODE_SYNCH_BEGIN_EVT:
1101 		case NODE_FAILOVER_BEGIN_EVT:
1102 		case NODE_FAILOVER_END_EVT:
1103 		default:
1104 			goto illegal_evt;
1105 		}
1106 		break;
1107 	case SELF_UP_PEER_UP:
1108 		switch (evt) {
1109 		case SELF_LOST_CONTACT_EVT:
1110 			state = SELF_DOWN_PEER_LEAVING;
1111 			break;
1112 		case PEER_LOST_CONTACT_EVT:
1113 			state = SELF_LEAVING_PEER_DOWN;
1114 			break;
1115 		case NODE_SYNCH_BEGIN_EVT:
1116 			state = NODE_SYNCHING;
1117 			break;
1118 		case NODE_FAILOVER_BEGIN_EVT:
1119 			state = NODE_FAILINGOVER;
1120 			break;
1121 		case SELF_ESTABL_CONTACT_EVT:
1122 		case PEER_ESTABL_CONTACT_EVT:
1123 		case NODE_SYNCH_END_EVT:
1124 		case NODE_FAILOVER_END_EVT:
1125 			break;
1126 		default:
1127 			goto illegal_evt;
1128 		}
1129 		break;
1130 	case SELF_DOWN_PEER_LEAVING:
1131 		switch (evt) {
1132 		case PEER_LOST_CONTACT_EVT:
1133 			state = SELF_DOWN_PEER_DOWN;
1134 			break;
1135 		case SELF_ESTABL_CONTACT_EVT:
1136 		case PEER_ESTABL_CONTACT_EVT:
1137 		case SELF_LOST_CONTACT_EVT:
1138 			break;
1139 		case NODE_SYNCH_END_EVT:
1140 		case NODE_SYNCH_BEGIN_EVT:
1141 		case NODE_FAILOVER_BEGIN_EVT:
1142 		case NODE_FAILOVER_END_EVT:
1143 		default:
1144 			goto illegal_evt;
1145 		}
1146 		break;
1147 	case SELF_UP_PEER_COMING:
1148 		switch (evt) {
1149 		case PEER_ESTABL_CONTACT_EVT:
1150 			state = SELF_UP_PEER_UP;
1151 			break;
1152 		case SELF_LOST_CONTACT_EVT:
1153 			state = SELF_DOWN_PEER_DOWN;
1154 			break;
1155 		case SELF_ESTABL_CONTACT_EVT:
1156 		case PEER_LOST_CONTACT_EVT:
1157 		case NODE_SYNCH_END_EVT:
1158 		case NODE_FAILOVER_BEGIN_EVT:
1159 			break;
1160 		case NODE_SYNCH_BEGIN_EVT:
1161 		case NODE_FAILOVER_END_EVT:
1162 		default:
1163 			goto illegal_evt;
1164 		}
1165 		break;
1166 	case SELF_COMING_PEER_UP:
1167 		switch (evt) {
1168 		case SELF_ESTABL_CONTACT_EVT:
1169 			state = SELF_UP_PEER_UP;
1170 			break;
1171 		case PEER_LOST_CONTACT_EVT:
1172 			state = SELF_DOWN_PEER_DOWN;
1173 			break;
1174 		case SELF_LOST_CONTACT_EVT:
1175 		case PEER_ESTABL_CONTACT_EVT:
1176 			break;
1177 		case NODE_SYNCH_END_EVT:
1178 		case NODE_SYNCH_BEGIN_EVT:
1179 		case NODE_FAILOVER_BEGIN_EVT:
1180 		case NODE_FAILOVER_END_EVT:
1181 		default:
1182 			goto illegal_evt;
1183 		}
1184 		break;
1185 	case SELF_LEAVING_PEER_DOWN:
1186 		switch (evt) {
1187 		case SELF_LOST_CONTACT_EVT:
1188 			state = SELF_DOWN_PEER_DOWN;
1189 			break;
1190 		case SELF_ESTABL_CONTACT_EVT:
1191 		case PEER_ESTABL_CONTACT_EVT:
1192 		case PEER_LOST_CONTACT_EVT:
1193 			break;
1194 		case NODE_SYNCH_END_EVT:
1195 		case NODE_SYNCH_BEGIN_EVT:
1196 		case NODE_FAILOVER_BEGIN_EVT:
1197 		case NODE_FAILOVER_END_EVT:
1198 		default:
1199 			goto illegal_evt;
1200 		}
1201 		break;
1202 	case NODE_FAILINGOVER:
1203 		switch (evt) {
1204 		case SELF_LOST_CONTACT_EVT:
1205 			state = SELF_DOWN_PEER_LEAVING;
1206 			break;
1207 		case PEER_LOST_CONTACT_EVT:
1208 			state = SELF_LEAVING_PEER_DOWN;
1209 			break;
1210 		case NODE_FAILOVER_END_EVT:
1211 			state = SELF_UP_PEER_UP;
1212 			break;
1213 		case NODE_FAILOVER_BEGIN_EVT:
1214 		case SELF_ESTABL_CONTACT_EVT:
1215 		case PEER_ESTABL_CONTACT_EVT:
1216 			break;
1217 		case NODE_SYNCH_BEGIN_EVT:
1218 		case NODE_SYNCH_END_EVT:
1219 		default:
1220 			goto illegal_evt;
1221 		}
1222 		break;
1223 	case NODE_SYNCHING:
1224 		switch (evt) {
1225 		case SELF_LOST_CONTACT_EVT:
1226 			state = SELF_DOWN_PEER_LEAVING;
1227 			break;
1228 		case PEER_LOST_CONTACT_EVT:
1229 			state = SELF_LEAVING_PEER_DOWN;
1230 			break;
1231 		case NODE_SYNCH_END_EVT:
1232 			state = SELF_UP_PEER_UP;
1233 			break;
1234 		case NODE_FAILOVER_BEGIN_EVT:
1235 			state = NODE_FAILINGOVER;
1236 			break;
1237 		case NODE_SYNCH_BEGIN_EVT:
1238 		case SELF_ESTABL_CONTACT_EVT:
1239 		case PEER_ESTABL_CONTACT_EVT:
1240 			break;
1241 		case NODE_FAILOVER_END_EVT:
1242 		default:
1243 			goto illegal_evt;
1244 		}
1245 		break;
1246 	default:
1247 		pr_err("Unknown node fsm state %x\n", state);
1248 		break;
1249 	}
1250 	trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
1251 	n->state = state;
1252 	return;
1253 
1254 illegal_evt:
1255 	pr_err("Illegal node fsm evt %x in state %x\n", evt, state);
1256 	trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
1257 }
1258 
1259 static void node_lost_contact(struct tipc_node *n,
1260 			      struct sk_buff_head *inputq)
1261 {
1262 	struct tipc_sock_conn *conn, *safe;
1263 	struct tipc_link *l;
1264 	struct list_head *conns = &n->conn_sks;
1265 	struct sk_buff *skb;
1266 	uint i;
1267 
1268 	pr_debug("Lost contact with %x\n", n->addr);
1269 	n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
1270 	trace_tipc_node_lost_contact(n, true, " ");
1271 
1272 	/* Clean up broadcast state */
1273 	tipc_bcast_remove_peer(n->net, n->bc_entry.link);
1274 
1275 	/* Abort any ongoing link failover */
1276 	for (i = 0; i < MAX_BEARERS; i++) {
1277 		l = n->links[i].link;
1278 		if (l)
1279 			tipc_link_fsm_evt(l, LINK_FAILOVER_END_EVT);
1280 	}
1281 
1282 	/* Notify publications from this node */
1283 	n->action_flags |= TIPC_NOTIFY_NODE_DOWN;
1284 
1285 	/* Notify sockets connected to node */
1286 	list_for_each_entry_safe(conn, safe, conns, list) {
1287 		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_CONN_MSG,
1288 				      SHORT_H_SIZE, 0, tipc_own_addr(n->net),
1289 				      conn->peer_node, conn->port,
1290 				      conn->peer_port, TIPC_ERR_NO_NODE);
1291 		if (likely(skb))
1292 			skb_queue_tail(inputq, skb);
1293 		list_del(&conn->list);
1294 		kfree(conn);
1295 	}
1296 }
1297 
1298 /**
1299  * tipc_node_get_linkname - get the name of a link
1300  *
1301  * @bearer_id: id of the bearer
1302  * @node: peer node address
1303  * @linkname: link name output buffer
1304  *
1305  * Returns 0 on success
1306  */
1307 int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 addr,
1308 			   char *linkname, size_t len)
1309 {
1310 	struct tipc_link *link;
1311 	int err = -EINVAL;
1312 	struct tipc_node *node = tipc_node_find(net, addr);
1313 
1314 	if (!node)
1315 		return err;
1316 
1317 	if (bearer_id >= MAX_BEARERS)
1318 		goto exit;
1319 
1320 	tipc_node_read_lock(node);
1321 	link = node->links[bearer_id].link;
1322 	if (link) {
1323 		strncpy(linkname, tipc_link_name(link), len);
1324 		err = 0;
1325 	}
1326 	tipc_node_read_unlock(node);
1327 exit:
1328 	tipc_node_put(node);
1329 	return err;
1330 }
1331 
1332 /* Caller should hold node lock for the passed node */
1333 static int __tipc_nl_add_node(struct tipc_nl_msg *msg, struct tipc_node *node)
1334 {
1335 	void *hdr;
1336 	struct nlattr *attrs;
1337 
1338 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1339 			  NLM_F_MULTI, TIPC_NL_NODE_GET);
1340 	if (!hdr)
1341 		return -EMSGSIZE;
1342 
1343 	attrs = nla_nest_start(msg->skb, TIPC_NLA_NODE);
1344 	if (!attrs)
1345 		goto msg_full;
1346 
1347 	if (nla_put_u32(msg->skb, TIPC_NLA_NODE_ADDR, node->addr))
1348 		goto attr_msg_full;
1349 	if (node_is_up(node))
1350 		if (nla_put_flag(msg->skb, TIPC_NLA_NODE_UP))
1351 			goto attr_msg_full;
1352 
1353 	nla_nest_end(msg->skb, attrs);
1354 	genlmsg_end(msg->skb, hdr);
1355 
1356 	return 0;
1357 
1358 attr_msg_full:
1359 	nla_nest_cancel(msg->skb, attrs);
1360 msg_full:
1361 	genlmsg_cancel(msg->skb, hdr);
1362 
1363 	return -EMSGSIZE;
1364 }
1365 
1366 /**
1367  * tipc_node_xmit() is the general link level function for message sending
1368  * @net: the applicable net namespace
1369  * @list: chain of buffers containing message
1370  * @dnode: address of destination node
1371  * @selector: a number used for deterministic link selection
1372  * Consumes the buffer chain.
1373  * Returns 0 if success, otherwise: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE,-ENOBUF
1374  */
1375 int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
1376 		   u32 dnode, int selector)
1377 {
1378 	struct tipc_link_entry *le = NULL;
1379 	struct tipc_node *n;
1380 	struct sk_buff_head xmitq;
1381 	int bearer_id;
1382 	int rc;
1383 
1384 	if (in_own_node(net, dnode)) {
1385 		tipc_sk_rcv(net, list);
1386 		return 0;
1387 	}
1388 
1389 	n = tipc_node_find(net, dnode);
1390 	if (unlikely(!n)) {
1391 		skb_queue_purge(list);
1392 		return -EHOSTUNREACH;
1393 	}
1394 
1395 	tipc_node_read_lock(n);
1396 	bearer_id = n->active_links[selector & 1];
1397 	if (unlikely(bearer_id == INVALID_BEARER_ID)) {
1398 		tipc_node_read_unlock(n);
1399 		tipc_node_put(n);
1400 		skb_queue_purge(list);
1401 		return -EHOSTUNREACH;
1402 	}
1403 
1404 	__skb_queue_head_init(&xmitq);
1405 	le = &n->links[bearer_id];
1406 	spin_lock_bh(&le->lock);
1407 	rc = tipc_link_xmit(le->link, list, &xmitq);
1408 	spin_unlock_bh(&le->lock);
1409 	tipc_node_read_unlock(n);
1410 
1411 	if (unlikely(rc == -ENOBUFS))
1412 		tipc_node_link_down(n, bearer_id, false);
1413 	else
1414 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr);
1415 
1416 	tipc_node_put(n);
1417 
1418 	return rc;
1419 }
1420 
1421 /* tipc_node_xmit_skb(): send single buffer to destination
1422  * Buffers sent via this functon are generally TIPC_SYSTEM_IMPORTANCE
1423  * messages, which will not be rejected
1424  * The only exception is datagram messages rerouted after secondary
1425  * lookup, which are rare and safe to dispose of anyway.
1426  */
1427 int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode,
1428 		       u32 selector)
1429 {
1430 	struct sk_buff_head head;
1431 
1432 	skb_queue_head_init(&head);
1433 	__skb_queue_tail(&head, skb);
1434 	tipc_node_xmit(net, &head, dnode, selector);
1435 	return 0;
1436 }
1437 
1438 /* tipc_node_distr_xmit(): send single buffer msgs to individual destinations
1439  * Note: this is only for SYSTEM_IMPORTANCE messages, which cannot be rejected
1440  */
1441 int tipc_node_distr_xmit(struct net *net, struct sk_buff_head *xmitq)
1442 {
1443 	struct sk_buff *skb;
1444 	u32 selector, dnode;
1445 
1446 	while ((skb = __skb_dequeue(xmitq))) {
1447 		selector = msg_origport(buf_msg(skb));
1448 		dnode = msg_destnode(buf_msg(skb));
1449 		tipc_node_xmit_skb(net, skb, dnode, selector);
1450 	}
1451 	return 0;
1452 }
1453 
1454 void tipc_node_broadcast(struct net *net, struct sk_buff *skb)
1455 {
1456 	struct sk_buff *txskb;
1457 	struct tipc_node *n;
1458 	u32 dst;
1459 
1460 	rcu_read_lock();
1461 	list_for_each_entry_rcu(n, tipc_nodes(net), list) {
1462 		dst = n->addr;
1463 		if (in_own_node(net, dst))
1464 			continue;
1465 		if (!node_is_up(n))
1466 			continue;
1467 		txskb = pskb_copy(skb, GFP_ATOMIC);
1468 		if (!txskb)
1469 			break;
1470 		msg_set_destnode(buf_msg(txskb), dst);
1471 		tipc_node_xmit_skb(net, txskb, dst, 0);
1472 	}
1473 	rcu_read_unlock();
1474 
1475 	kfree_skb(skb);
1476 }
1477 
1478 static void tipc_node_mcast_rcv(struct tipc_node *n)
1479 {
1480 	struct tipc_bclink_entry *be = &n->bc_entry;
1481 
1482 	/* 'arrvq' is under inputq2's lock protection */
1483 	spin_lock_bh(&be->inputq2.lock);
1484 	spin_lock_bh(&be->inputq1.lock);
1485 	skb_queue_splice_tail_init(&be->inputq1, &be->arrvq);
1486 	spin_unlock_bh(&be->inputq1.lock);
1487 	spin_unlock_bh(&be->inputq2.lock);
1488 	tipc_sk_mcast_rcv(n->net, &be->arrvq, &be->inputq2);
1489 }
1490 
1491 static void tipc_node_bc_sync_rcv(struct tipc_node *n, struct tipc_msg *hdr,
1492 				  int bearer_id, struct sk_buff_head *xmitq)
1493 {
1494 	struct tipc_link *ucl;
1495 	int rc;
1496 
1497 	rc = tipc_bcast_sync_rcv(n->net, n->bc_entry.link, hdr);
1498 
1499 	if (rc & TIPC_LINK_DOWN_EVT) {
1500 		tipc_node_reset_links(n);
1501 		return;
1502 	}
1503 
1504 	if (!(rc & TIPC_LINK_SND_STATE))
1505 		return;
1506 
1507 	/* If probe message, a STATE response will be sent anyway */
1508 	if (msg_probe(hdr))
1509 		return;
1510 
1511 	/* Produce a STATE message carrying broadcast NACK */
1512 	tipc_node_read_lock(n);
1513 	ucl = n->links[bearer_id].link;
1514 	if (ucl)
1515 		tipc_link_build_state_msg(ucl, xmitq);
1516 	tipc_node_read_unlock(n);
1517 }
1518 
1519 /**
1520  * tipc_node_bc_rcv - process TIPC broadcast packet arriving from off-node
1521  * @net: the applicable net namespace
1522  * @skb: TIPC packet
1523  * @bearer_id: id of bearer message arrived on
1524  *
1525  * Invoked with no locks held.
1526  */
1527 static void tipc_node_bc_rcv(struct net *net, struct sk_buff *skb, int bearer_id)
1528 {
1529 	int rc;
1530 	struct sk_buff_head xmitq;
1531 	struct tipc_bclink_entry *be;
1532 	struct tipc_link_entry *le;
1533 	struct tipc_msg *hdr = buf_msg(skb);
1534 	int usr = msg_user(hdr);
1535 	u32 dnode = msg_destnode(hdr);
1536 	struct tipc_node *n;
1537 
1538 	__skb_queue_head_init(&xmitq);
1539 
1540 	/* If NACK for other node, let rcv link for that node peek into it */
1541 	if ((usr == BCAST_PROTOCOL) && (dnode != tipc_own_addr(net)))
1542 		n = tipc_node_find(net, dnode);
1543 	else
1544 		n = tipc_node_find(net, msg_prevnode(hdr));
1545 	if (!n) {
1546 		kfree_skb(skb);
1547 		return;
1548 	}
1549 	be = &n->bc_entry;
1550 	le = &n->links[bearer_id];
1551 
1552 	rc = tipc_bcast_rcv(net, be->link, skb);
1553 
1554 	/* Broadcast ACKs are sent on a unicast link */
1555 	if (rc & TIPC_LINK_SND_STATE) {
1556 		tipc_node_read_lock(n);
1557 		tipc_link_build_state_msg(le->link, &xmitq);
1558 		tipc_node_read_unlock(n);
1559 	}
1560 
1561 	if (!skb_queue_empty(&xmitq))
1562 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr);
1563 
1564 	if (!skb_queue_empty(&be->inputq1))
1565 		tipc_node_mcast_rcv(n);
1566 
1567 	/* Handle NAME_DISTRIBUTOR messages sent from 1.7 nodes */
1568 	if (!skb_queue_empty(&n->bc_entry.namedq))
1569 		tipc_named_rcv(net, &n->bc_entry.namedq);
1570 
1571 	/* If reassembly or retransmission failure => reset all links to peer */
1572 	if (rc & TIPC_LINK_DOWN_EVT)
1573 		tipc_node_reset_links(n);
1574 
1575 	tipc_node_put(n);
1576 }
1577 
1578 /**
1579  * tipc_node_check_state - check and if necessary update node state
1580  * @skb: TIPC packet
1581  * @bearer_id: identity of bearer delivering the packet
1582  * Returns true if state and msg are ok, otherwise false
1583  */
1584 static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
1585 				  int bearer_id, struct sk_buff_head *xmitq)
1586 {
1587 	struct tipc_msg *hdr = buf_msg(skb);
1588 	int usr = msg_user(hdr);
1589 	int mtyp = msg_type(hdr);
1590 	u16 oseqno = msg_seqno(hdr);
1591 	u16 iseqno = msg_seqno(msg_get_wrapped(hdr));
1592 	u16 exp_pkts = msg_msgcnt(hdr);
1593 	u16 rcv_nxt, syncpt, dlv_nxt, inputq_len;
1594 	int state = n->state;
1595 	struct tipc_link *l, *tnl, *pl = NULL;
1596 	struct tipc_media_addr *maddr;
1597 	int pb_id;
1598 
1599 	if (trace_tipc_node_check_state_enabled()) {
1600 		trace_tipc_skb_dump(skb, false, "skb for node state check");
1601 		trace_tipc_node_check_state(n, true, " ");
1602 	}
1603 	l = n->links[bearer_id].link;
1604 	if (!l)
1605 		return false;
1606 	rcv_nxt = tipc_link_rcv_nxt(l);
1607 
1608 
1609 	if (likely((state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL)))
1610 		return true;
1611 
1612 	/* Find parallel link, if any */
1613 	for (pb_id = 0; pb_id < MAX_BEARERS; pb_id++) {
1614 		if ((pb_id != bearer_id) && n->links[pb_id].link) {
1615 			pl = n->links[pb_id].link;
1616 			break;
1617 		}
1618 	}
1619 
1620 	if (!tipc_link_validate_msg(l, hdr)) {
1621 		trace_tipc_skb_dump(skb, false, "PROTO invalid (2)!");
1622 		trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (2)!");
1623 		return false;
1624 	}
1625 
1626 	/* Check and update node accesibility if applicable */
1627 	if (state == SELF_UP_PEER_COMING) {
1628 		if (!tipc_link_is_up(l))
1629 			return true;
1630 		if (!msg_peer_link_is_up(hdr))
1631 			return true;
1632 		tipc_node_fsm_evt(n, PEER_ESTABL_CONTACT_EVT);
1633 	}
1634 
1635 	if (state == SELF_DOWN_PEER_LEAVING) {
1636 		if (msg_peer_node_is_up(hdr))
1637 			return false;
1638 		tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
1639 		return true;
1640 	}
1641 
1642 	if (state == SELF_LEAVING_PEER_DOWN)
1643 		return false;
1644 
1645 	/* Ignore duplicate packets */
1646 	if ((usr != LINK_PROTOCOL) && less(oseqno, rcv_nxt))
1647 		return true;
1648 
1649 	/* Initiate or update failover mode if applicable */
1650 	if ((usr == TUNNEL_PROTOCOL) && (mtyp == FAILOVER_MSG)) {
1651 		syncpt = oseqno + exp_pkts - 1;
1652 		if (pl && tipc_link_is_up(pl)) {
1653 			__tipc_node_link_down(n, &pb_id, xmitq, &maddr);
1654 			trace_tipc_node_link_down(n, true,
1655 						  "node link down <- failover!");
1656 			tipc_skb_queue_splice_tail_init(tipc_link_inputq(pl),
1657 							tipc_link_inputq(l));
1658 		}
1659 		/* If parallel link was already down, and this happened before
1660 		 * the tunnel link came up, FAILOVER was never sent. Ensure that
1661 		 * FAILOVER is sent to get peer out of NODE_FAILINGOVER state.
1662 		 */
1663 		if (n->state != NODE_FAILINGOVER && !n->failover_sent) {
1664 			tipc_link_create_dummy_tnl_msg(l, xmitq);
1665 			n->failover_sent = true;
1666 		}
1667 		/* If pkts arrive out of order, use lowest calculated syncpt */
1668 		if (less(syncpt, n->sync_point))
1669 			n->sync_point = syncpt;
1670 	}
1671 
1672 	/* Open parallel link when tunnel link reaches synch point */
1673 	if ((n->state == NODE_FAILINGOVER) && tipc_link_is_up(l)) {
1674 		if (!more(rcv_nxt, n->sync_point))
1675 			return true;
1676 		tipc_node_fsm_evt(n, NODE_FAILOVER_END_EVT);
1677 		if (pl)
1678 			tipc_link_fsm_evt(pl, LINK_FAILOVER_END_EVT);
1679 		return true;
1680 	}
1681 
1682 	/* No synching needed if only one link */
1683 	if (!pl || !tipc_link_is_up(pl))
1684 		return true;
1685 
1686 	/* Initiate synch mode if applicable */
1687 	if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG) && (oseqno == 1)) {
1688 		syncpt = iseqno + exp_pkts - 1;
1689 		if (!tipc_link_is_up(l))
1690 			__tipc_node_link_up(n, bearer_id, xmitq);
1691 		if (n->state == SELF_UP_PEER_UP) {
1692 			n->sync_point = syncpt;
1693 			tipc_link_fsm_evt(l, LINK_SYNCH_BEGIN_EVT);
1694 			tipc_node_fsm_evt(n, NODE_SYNCH_BEGIN_EVT);
1695 		}
1696 	}
1697 
1698 	/* Open tunnel link when parallel link reaches synch point */
1699 	if (n->state == NODE_SYNCHING) {
1700 		if (tipc_link_is_synching(l)) {
1701 			tnl = l;
1702 		} else {
1703 			tnl = pl;
1704 			pl = l;
1705 		}
1706 		inputq_len = skb_queue_len(tipc_link_inputq(pl));
1707 		dlv_nxt = tipc_link_rcv_nxt(pl) - inputq_len;
1708 		if (more(dlv_nxt, n->sync_point)) {
1709 			tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
1710 			tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
1711 			return true;
1712 		}
1713 		if (l == pl)
1714 			return true;
1715 		if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG))
1716 			return true;
1717 		if (usr == LINK_PROTOCOL)
1718 			return true;
1719 		return false;
1720 	}
1721 	return true;
1722 }
1723 
1724 /**
1725  * tipc_rcv - process TIPC packets/messages arriving from off-node
1726  * @net: the applicable net namespace
1727  * @skb: TIPC packet
1728  * @bearer: pointer to bearer message arrived on
1729  *
1730  * Invoked with no locks held. Bearer pointer must point to a valid bearer
1731  * structure (i.e. cannot be NULL), but bearer can be inactive.
1732  */
1733 void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
1734 {
1735 	struct sk_buff_head xmitq;
1736 	struct tipc_node *n;
1737 	struct tipc_msg *hdr;
1738 	int bearer_id = b->identity;
1739 	struct tipc_link_entry *le;
1740 	u32 self = tipc_own_addr(net);
1741 	int usr, rc = 0;
1742 	u16 bc_ack;
1743 
1744 	__skb_queue_head_init(&xmitq);
1745 
1746 	/* Ensure message is well-formed before touching the header */
1747 	if (unlikely(!tipc_msg_validate(&skb)))
1748 		goto discard;
1749 	hdr = buf_msg(skb);
1750 	usr = msg_user(hdr);
1751 	bc_ack = msg_bcast_ack(hdr);
1752 
1753 	/* Handle arrival of discovery or broadcast packet */
1754 	if (unlikely(msg_non_seq(hdr))) {
1755 		if (unlikely(usr == LINK_CONFIG))
1756 			return tipc_disc_rcv(net, skb, b);
1757 		else
1758 			return tipc_node_bc_rcv(net, skb, bearer_id);
1759 	}
1760 
1761 	/* Discard unicast link messages destined for another node */
1762 	if (unlikely(!msg_short(hdr) && (msg_destnode(hdr) != self)))
1763 		goto discard;
1764 
1765 	/* Locate neighboring node that sent packet */
1766 	n = tipc_node_find(net, msg_prevnode(hdr));
1767 	if (unlikely(!n))
1768 		goto discard;
1769 	le = &n->links[bearer_id];
1770 
1771 	/* Ensure broadcast reception is in synch with peer's send state */
1772 	if (unlikely(usr == LINK_PROTOCOL))
1773 		tipc_node_bc_sync_rcv(n, hdr, bearer_id, &xmitq);
1774 	else if (unlikely(tipc_link_acked(n->bc_entry.link) != bc_ack))
1775 		tipc_bcast_ack_rcv(net, n->bc_entry.link, hdr);
1776 
1777 	/* Receive packet directly if conditions permit */
1778 	tipc_node_read_lock(n);
1779 	if (likely((n->state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL))) {
1780 		spin_lock_bh(&le->lock);
1781 		if (le->link) {
1782 			rc = tipc_link_rcv(le->link, skb, &xmitq);
1783 			skb = NULL;
1784 		}
1785 		spin_unlock_bh(&le->lock);
1786 	}
1787 	tipc_node_read_unlock(n);
1788 
1789 	/* Check/update node state before receiving */
1790 	if (unlikely(skb)) {
1791 		if (unlikely(skb_linearize(skb)))
1792 			goto discard;
1793 		tipc_node_write_lock(n);
1794 		if (tipc_node_check_state(n, skb, bearer_id, &xmitq)) {
1795 			if (le->link) {
1796 				rc = tipc_link_rcv(le->link, skb, &xmitq);
1797 				skb = NULL;
1798 			}
1799 		}
1800 		tipc_node_write_unlock(n);
1801 	}
1802 
1803 	if (unlikely(rc & TIPC_LINK_UP_EVT))
1804 		tipc_node_link_up(n, bearer_id, &xmitq);
1805 
1806 	if (unlikely(rc & TIPC_LINK_DOWN_EVT))
1807 		tipc_node_link_down(n, bearer_id, false);
1808 
1809 	if (unlikely(!skb_queue_empty(&n->bc_entry.namedq)))
1810 		tipc_named_rcv(net, &n->bc_entry.namedq);
1811 
1812 	if (unlikely(!skb_queue_empty(&n->bc_entry.inputq1)))
1813 		tipc_node_mcast_rcv(n);
1814 
1815 	if (!skb_queue_empty(&le->inputq))
1816 		tipc_sk_rcv(net, &le->inputq);
1817 
1818 	if (!skb_queue_empty(&xmitq))
1819 		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr);
1820 
1821 	tipc_node_put(n);
1822 discard:
1823 	kfree_skb(skb);
1824 }
1825 
1826 void tipc_node_apply_property(struct net *net, struct tipc_bearer *b,
1827 			      int prop)
1828 {
1829 	struct tipc_net *tn = tipc_net(net);
1830 	int bearer_id = b->identity;
1831 	struct sk_buff_head xmitq;
1832 	struct tipc_link_entry *e;
1833 	struct tipc_node *n;
1834 
1835 	__skb_queue_head_init(&xmitq);
1836 
1837 	rcu_read_lock();
1838 
1839 	list_for_each_entry_rcu(n, &tn->node_list, list) {
1840 		tipc_node_write_lock(n);
1841 		e = &n->links[bearer_id];
1842 		if (e->link) {
1843 			if (prop == TIPC_NLA_PROP_TOL)
1844 				tipc_link_set_tolerance(e->link, b->tolerance,
1845 							&xmitq);
1846 			else if (prop == TIPC_NLA_PROP_MTU)
1847 				tipc_link_set_mtu(e->link, b->mtu);
1848 		}
1849 		tipc_node_write_unlock(n);
1850 		tipc_bearer_xmit(net, bearer_id, &xmitq, &e->maddr);
1851 	}
1852 
1853 	rcu_read_unlock();
1854 }
1855 
1856 int tipc_nl_peer_rm(struct sk_buff *skb, struct genl_info *info)
1857 {
1858 	struct net *net = sock_net(skb->sk);
1859 	struct tipc_net *tn = net_generic(net, tipc_net_id);
1860 	struct nlattr *attrs[TIPC_NLA_NET_MAX + 1];
1861 	struct tipc_node *peer;
1862 	u32 addr;
1863 	int err;
1864 
1865 	/* We identify the peer by its net */
1866 	if (!info->attrs[TIPC_NLA_NET])
1867 		return -EINVAL;
1868 
1869 	err = nla_parse_nested(attrs, TIPC_NLA_NET_MAX,
1870 			       info->attrs[TIPC_NLA_NET], tipc_nl_net_policy,
1871 			       info->extack);
1872 	if (err)
1873 		return err;
1874 
1875 	if (!attrs[TIPC_NLA_NET_ADDR])
1876 		return -EINVAL;
1877 
1878 	addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]);
1879 
1880 	if (in_own_node(net, addr))
1881 		return -ENOTSUPP;
1882 
1883 	spin_lock_bh(&tn->node_list_lock);
1884 	peer = tipc_node_find(net, addr);
1885 	if (!peer) {
1886 		spin_unlock_bh(&tn->node_list_lock);
1887 		return -ENXIO;
1888 	}
1889 
1890 	tipc_node_write_lock(peer);
1891 	if (peer->state != SELF_DOWN_PEER_DOWN &&
1892 	    peer->state != SELF_DOWN_PEER_LEAVING) {
1893 		tipc_node_write_unlock(peer);
1894 		err = -EBUSY;
1895 		goto err_out;
1896 	}
1897 
1898 	tipc_node_clear_links(peer);
1899 	tipc_node_write_unlock(peer);
1900 	tipc_node_delete(peer);
1901 
1902 	err = 0;
1903 err_out:
1904 	tipc_node_put(peer);
1905 	spin_unlock_bh(&tn->node_list_lock);
1906 
1907 	return err;
1908 }
1909 
1910 int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb)
1911 {
1912 	int err;
1913 	struct net *net = sock_net(skb->sk);
1914 	struct tipc_net *tn = net_generic(net, tipc_net_id);
1915 	int done = cb->args[0];
1916 	int last_addr = cb->args[1];
1917 	struct tipc_node *node;
1918 	struct tipc_nl_msg msg;
1919 
1920 	if (done)
1921 		return 0;
1922 
1923 	msg.skb = skb;
1924 	msg.portid = NETLINK_CB(cb->skb).portid;
1925 	msg.seq = cb->nlh->nlmsg_seq;
1926 
1927 	rcu_read_lock();
1928 	if (last_addr) {
1929 		node = tipc_node_find(net, last_addr);
1930 		if (!node) {
1931 			rcu_read_unlock();
1932 			/* We never set seq or call nl_dump_check_consistent()
1933 			 * this means that setting prev_seq here will cause the
1934 			 * consistence check to fail in the netlink callback
1935 			 * handler. Resulting in the NLMSG_DONE message having
1936 			 * the NLM_F_DUMP_INTR flag set if the node state
1937 			 * changed while we released the lock.
1938 			 */
1939 			cb->prev_seq = 1;
1940 			return -EPIPE;
1941 		}
1942 		tipc_node_put(node);
1943 	}
1944 
1945 	list_for_each_entry_rcu(node, &tn->node_list, list) {
1946 		if (last_addr) {
1947 			if (node->addr == last_addr)
1948 				last_addr = 0;
1949 			else
1950 				continue;
1951 		}
1952 
1953 		tipc_node_read_lock(node);
1954 		err = __tipc_nl_add_node(&msg, node);
1955 		if (err) {
1956 			last_addr = node->addr;
1957 			tipc_node_read_unlock(node);
1958 			goto out;
1959 		}
1960 
1961 		tipc_node_read_unlock(node);
1962 	}
1963 	done = 1;
1964 out:
1965 	cb->args[0] = done;
1966 	cb->args[1] = last_addr;
1967 	rcu_read_unlock();
1968 
1969 	return skb->len;
1970 }
1971 
1972 /* tipc_node_find_by_name - locate owner node of link by link's name
1973  * @net: the applicable net namespace
1974  * @name: pointer to link name string
1975  * @bearer_id: pointer to index in 'node->links' array where the link was found.
1976  *
1977  * Returns pointer to node owning the link, or 0 if no matching link is found.
1978  */
1979 static struct tipc_node *tipc_node_find_by_name(struct net *net,
1980 						const char *link_name,
1981 						unsigned int *bearer_id)
1982 {
1983 	struct tipc_net *tn = net_generic(net, tipc_net_id);
1984 	struct tipc_link *l;
1985 	struct tipc_node *n;
1986 	struct tipc_node *found_node = NULL;
1987 	int i;
1988 
1989 	*bearer_id = 0;
1990 	rcu_read_lock();
1991 	list_for_each_entry_rcu(n, &tn->node_list, list) {
1992 		tipc_node_read_lock(n);
1993 		for (i = 0; i < MAX_BEARERS; i++) {
1994 			l = n->links[i].link;
1995 			if (l && !strcmp(tipc_link_name(l), link_name)) {
1996 				*bearer_id = i;
1997 				found_node = n;
1998 				break;
1999 			}
2000 		}
2001 		tipc_node_read_unlock(n);
2002 		if (found_node)
2003 			break;
2004 	}
2005 	rcu_read_unlock();
2006 
2007 	return found_node;
2008 }
2009 
2010 int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info)
2011 {
2012 	int err;
2013 	int res = 0;
2014 	int bearer_id;
2015 	char *name;
2016 	struct tipc_link *link;
2017 	struct tipc_node *node;
2018 	struct sk_buff_head xmitq;
2019 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2020 	struct net *net = sock_net(skb->sk);
2021 
2022 	__skb_queue_head_init(&xmitq);
2023 
2024 	if (!info->attrs[TIPC_NLA_LINK])
2025 		return -EINVAL;
2026 
2027 	err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
2028 			       info->attrs[TIPC_NLA_LINK],
2029 			       tipc_nl_link_policy, info->extack);
2030 	if (err)
2031 		return err;
2032 
2033 	if (!attrs[TIPC_NLA_LINK_NAME])
2034 		return -EINVAL;
2035 
2036 	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2037 
2038 	if (strcmp(name, tipc_bclink_name) == 0)
2039 		return tipc_nl_bc_link_set(net, attrs);
2040 
2041 	node = tipc_node_find_by_name(net, name, &bearer_id);
2042 	if (!node)
2043 		return -EINVAL;
2044 
2045 	tipc_node_read_lock(node);
2046 
2047 	link = node->links[bearer_id].link;
2048 	if (!link) {
2049 		res = -EINVAL;
2050 		goto out;
2051 	}
2052 
2053 	if (attrs[TIPC_NLA_LINK_PROP]) {
2054 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
2055 
2056 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP],
2057 					      props);
2058 		if (err) {
2059 			res = err;
2060 			goto out;
2061 		}
2062 
2063 		if (props[TIPC_NLA_PROP_TOL]) {
2064 			u32 tol;
2065 
2066 			tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2067 			tipc_link_set_tolerance(link, tol, &xmitq);
2068 		}
2069 		if (props[TIPC_NLA_PROP_PRIO]) {
2070 			u32 prio;
2071 
2072 			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2073 			tipc_link_set_prio(link, prio, &xmitq);
2074 		}
2075 		if (props[TIPC_NLA_PROP_WIN]) {
2076 			u32 win;
2077 
2078 			win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2079 			tipc_link_set_queue_limits(link, win);
2080 		}
2081 	}
2082 
2083 out:
2084 	tipc_node_read_unlock(node);
2085 	tipc_bearer_xmit(net, bearer_id, &xmitq, &node->links[bearer_id].maddr);
2086 	return res;
2087 }
2088 
2089 int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info)
2090 {
2091 	struct net *net = genl_info_net(info);
2092 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2093 	struct tipc_nl_msg msg;
2094 	char *name;
2095 	int err;
2096 
2097 	msg.portid = info->snd_portid;
2098 	msg.seq = info->snd_seq;
2099 
2100 	if (!info->attrs[TIPC_NLA_LINK])
2101 		return -EINVAL;
2102 
2103 	err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
2104 			       info->attrs[TIPC_NLA_LINK],
2105 			       tipc_nl_link_policy, info->extack);
2106 	if (err)
2107 		return err;
2108 
2109 	if (!attrs[TIPC_NLA_LINK_NAME])
2110 		return -EINVAL;
2111 
2112 	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2113 
2114 	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2115 	if (!msg.skb)
2116 		return -ENOMEM;
2117 
2118 	if (strcmp(name, tipc_bclink_name) == 0) {
2119 		err = tipc_nl_add_bc_link(net, &msg);
2120 		if (err)
2121 			goto err_free;
2122 	} else {
2123 		int bearer_id;
2124 		struct tipc_node *node;
2125 		struct tipc_link *link;
2126 
2127 		node = tipc_node_find_by_name(net, name, &bearer_id);
2128 		if (!node) {
2129 			err = -EINVAL;
2130 			goto err_free;
2131 		}
2132 
2133 		tipc_node_read_lock(node);
2134 		link = node->links[bearer_id].link;
2135 		if (!link) {
2136 			tipc_node_read_unlock(node);
2137 			err = -EINVAL;
2138 			goto err_free;
2139 		}
2140 
2141 		err = __tipc_nl_add_link(net, &msg, link, 0);
2142 		tipc_node_read_unlock(node);
2143 		if (err)
2144 			goto err_free;
2145 	}
2146 
2147 	return genlmsg_reply(msg.skb, info);
2148 
2149 err_free:
2150 	nlmsg_free(msg.skb);
2151 	return err;
2152 }
2153 
2154 int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info)
2155 {
2156 	int err;
2157 	char *link_name;
2158 	unsigned int bearer_id;
2159 	struct tipc_link *link;
2160 	struct tipc_node *node;
2161 	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2162 	struct net *net = sock_net(skb->sk);
2163 	struct tipc_link_entry *le;
2164 
2165 	if (!info->attrs[TIPC_NLA_LINK])
2166 		return -EINVAL;
2167 
2168 	err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
2169 			       info->attrs[TIPC_NLA_LINK],
2170 			       tipc_nl_link_policy, info->extack);
2171 	if (err)
2172 		return err;
2173 
2174 	if (!attrs[TIPC_NLA_LINK_NAME])
2175 		return -EINVAL;
2176 
2177 	link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2178 
2179 	if (strcmp(link_name, tipc_bclink_name) == 0) {
2180 		err = tipc_bclink_reset_stats(net);
2181 		if (err)
2182 			return err;
2183 		return 0;
2184 	}
2185 
2186 	node = tipc_node_find_by_name(net, link_name, &bearer_id);
2187 	if (!node)
2188 		return -EINVAL;
2189 
2190 	le = &node->links[bearer_id];
2191 	tipc_node_read_lock(node);
2192 	spin_lock_bh(&le->lock);
2193 	link = node->links[bearer_id].link;
2194 	if (!link) {
2195 		spin_unlock_bh(&le->lock);
2196 		tipc_node_read_unlock(node);
2197 		return -EINVAL;
2198 	}
2199 	tipc_link_reset_stats(link);
2200 	spin_unlock_bh(&le->lock);
2201 	tipc_node_read_unlock(node);
2202 	return 0;
2203 }
2204 
2205 /* Caller should hold node lock  */
2206 static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
2207 				    struct tipc_node *node, u32 *prev_link)
2208 {
2209 	u32 i;
2210 	int err;
2211 
2212 	for (i = *prev_link; i < MAX_BEARERS; i++) {
2213 		*prev_link = i;
2214 
2215 		if (!node->links[i].link)
2216 			continue;
2217 
2218 		err = __tipc_nl_add_link(net, msg,
2219 					 node->links[i].link, NLM_F_MULTI);
2220 		if (err)
2221 			return err;
2222 	}
2223 	*prev_link = 0;
2224 
2225 	return 0;
2226 }
2227 
2228 int tipc_nl_node_dump_link(struct sk_buff *skb, struct netlink_callback *cb)
2229 {
2230 	struct net *net = sock_net(skb->sk);
2231 	struct tipc_net *tn = net_generic(net, tipc_net_id);
2232 	struct tipc_node *node;
2233 	struct tipc_nl_msg msg;
2234 	u32 prev_node = cb->args[0];
2235 	u32 prev_link = cb->args[1];
2236 	int done = cb->args[2];
2237 	int err;
2238 
2239 	if (done)
2240 		return 0;
2241 
2242 	msg.skb = skb;
2243 	msg.portid = NETLINK_CB(cb->skb).portid;
2244 	msg.seq = cb->nlh->nlmsg_seq;
2245 
2246 	rcu_read_lock();
2247 	if (prev_node) {
2248 		node = tipc_node_find(net, prev_node);
2249 		if (!node) {
2250 			/* We never set seq or call nl_dump_check_consistent()
2251 			 * this means that setting prev_seq here will cause the
2252 			 * consistence check to fail in the netlink callback
2253 			 * handler. Resulting in the last NLMSG_DONE message
2254 			 * having the NLM_F_DUMP_INTR flag set.
2255 			 */
2256 			cb->prev_seq = 1;
2257 			goto out;
2258 		}
2259 		tipc_node_put(node);
2260 
2261 		list_for_each_entry_continue_rcu(node, &tn->node_list,
2262 						 list) {
2263 			tipc_node_read_lock(node);
2264 			err = __tipc_nl_add_node_links(net, &msg, node,
2265 						       &prev_link);
2266 			tipc_node_read_unlock(node);
2267 			if (err)
2268 				goto out;
2269 
2270 			prev_node = node->addr;
2271 		}
2272 	} else {
2273 		err = tipc_nl_add_bc_link(net, &msg);
2274 		if (err)
2275 			goto out;
2276 
2277 		list_for_each_entry_rcu(node, &tn->node_list, list) {
2278 			tipc_node_read_lock(node);
2279 			err = __tipc_nl_add_node_links(net, &msg, node,
2280 						       &prev_link);
2281 			tipc_node_read_unlock(node);
2282 			if (err)
2283 				goto out;
2284 
2285 			prev_node = node->addr;
2286 		}
2287 	}
2288 	done = 1;
2289 out:
2290 	rcu_read_unlock();
2291 
2292 	cb->args[0] = prev_node;
2293 	cb->args[1] = prev_link;
2294 	cb->args[2] = done;
2295 
2296 	return skb->len;
2297 }
2298 
2299 int tipc_nl_node_set_monitor(struct sk_buff *skb, struct genl_info *info)
2300 {
2301 	struct nlattr *attrs[TIPC_NLA_MON_MAX + 1];
2302 	struct net *net = sock_net(skb->sk);
2303 	int err;
2304 
2305 	if (!info->attrs[TIPC_NLA_MON])
2306 		return -EINVAL;
2307 
2308 	err = nla_parse_nested(attrs, TIPC_NLA_MON_MAX,
2309 			       info->attrs[TIPC_NLA_MON],
2310 			       tipc_nl_monitor_policy, info->extack);
2311 	if (err)
2312 		return err;
2313 
2314 	if (attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]) {
2315 		u32 val;
2316 
2317 		val = nla_get_u32(attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]);
2318 		err = tipc_nl_monitor_set_threshold(net, val);
2319 		if (err)
2320 			return err;
2321 	}
2322 
2323 	return 0;
2324 }
2325 
2326 static int __tipc_nl_add_monitor_prop(struct net *net, struct tipc_nl_msg *msg)
2327 {
2328 	struct nlattr *attrs;
2329 	void *hdr;
2330 	u32 val;
2331 
2332 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2333 			  0, TIPC_NL_MON_GET);
2334 	if (!hdr)
2335 		return -EMSGSIZE;
2336 
2337 	attrs = nla_nest_start(msg->skb, TIPC_NLA_MON);
2338 	if (!attrs)
2339 		goto msg_full;
2340 
2341 	val = tipc_nl_monitor_get_threshold(net);
2342 
2343 	if (nla_put_u32(msg->skb, TIPC_NLA_MON_ACTIVATION_THRESHOLD, val))
2344 		goto attr_msg_full;
2345 
2346 	nla_nest_end(msg->skb, attrs);
2347 	genlmsg_end(msg->skb, hdr);
2348 
2349 	return 0;
2350 
2351 attr_msg_full:
2352 	nla_nest_cancel(msg->skb, attrs);
2353 msg_full:
2354 	genlmsg_cancel(msg->skb, hdr);
2355 
2356 	return -EMSGSIZE;
2357 }
2358 
2359 int tipc_nl_node_get_monitor(struct sk_buff *skb, struct genl_info *info)
2360 {
2361 	struct net *net = sock_net(skb->sk);
2362 	struct tipc_nl_msg msg;
2363 	int err;
2364 
2365 	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2366 	if (!msg.skb)
2367 		return -ENOMEM;
2368 	msg.portid = info->snd_portid;
2369 	msg.seq = info->snd_seq;
2370 
2371 	err = __tipc_nl_add_monitor_prop(net, &msg);
2372 	if (err) {
2373 		nlmsg_free(msg.skb);
2374 		return err;
2375 	}
2376 
2377 	return genlmsg_reply(msg.skb, info);
2378 }
2379 
2380 int tipc_nl_node_dump_monitor(struct sk_buff *skb, struct netlink_callback *cb)
2381 {
2382 	struct net *net = sock_net(skb->sk);
2383 	u32 prev_bearer = cb->args[0];
2384 	struct tipc_nl_msg msg;
2385 	int bearer_id;
2386 	int err;
2387 
2388 	if (prev_bearer == MAX_BEARERS)
2389 		return 0;
2390 
2391 	msg.skb = skb;
2392 	msg.portid = NETLINK_CB(cb->skb).portid;
2393 	msg.seq = cb->nlh->nlmsg_seq;
2394 
2395 	rtnl_lock();
2396 	for (bearer_id = prev_bearer; bearer_id < MAX_BEARERS; bearer_id++) {
2397 		err = __tipc_nl_add_monitor(net, &msg, bearer_id);
2398 		if (err)
2399 			break;
2400 	}
2401 	rtnl_unlock();
2402 	cb->args[0] = bearer_id;
2403 
2404 	return skb->len;
2405 }
2406 
2407 int tipc_nl_node_dump_monitor_peer(struct sk_buff *skb,
2408 				   struct netlink_callback *cb)
2409 {
2410 	struct net *net = sock_net(skb->sk);
2411 	u32 prev_node = cb->args[1];
2412 	u32 bearer_id = cb->args[2];
2413 	int done = cb->args[0];
2414 	struct tipc_nl_msg msg;
2415 	int err;
2416 
2417 	if (!prev_node) {
2418 		struct nlattr **attrs;
2419 		struct nlattr *mon[TIPC_NLA_MON_MAX + 1];
2420 
2421 		err = tipc_nlmsg_parse(cb->nlh, &attrs);
2422 		if (err)
2423 			return err;
2424 
2425 		if (!attrs[TIPC_NLA_MON])
2426 			return -EINVAL;
2427 
2428 		err = nla_parse_nested(mon, TIPC_NLA_MON_MAX,
2429 				       attrs[TIPC_NLA_MON],
2430 				       tipc_nl_monitor_policy, NULL);
2431 		if (err)
2432 			return err;
2433 
2434 		if (!mon[TIPC_NLA_MON_REF])
2435 			return -EINVAL;
2436 
2437 		bearer_id = nla_get_u32(mon[TIPC_NLA_MON_REF]);
2438 
2439 		if (bearer_id >= MAX_BEARERS)
2440 			return -EINVAL;
2441 	}
2442 
2443 	if (done)
2444 		return 0;
2445 
2446 	msg.skb = skb;
2447 	msg.portid = NETLINK_CB(cb->skb).portid;
2448 	msg.seq = cb->nlh->nlmsg_seq;
2449 
2450 	rtnl_lock();
2451 	err = tipc_nl_add_monitor_peer(net, &msg, bearer_id, &prev_node);
2452 	if (!err)
2453 		done = 1;
2454 
2455 	rtnl_unlock();
2456 	cb->args[0] = done;
2457 	cb->args[1] = prev_node;
2458 	cb->args[2] = bearer_id;
2459 
2460 	return skb->len;
2461 }
2462 
2463 u32 tipc_node_get_addr(struct tipc_node *node)
2464 {
2465 	return (node) ? node->addr : 0;
2466 }
2467 
2468 /**
2469  * tipc_node_dump - dump TIPC node data
2470  * @n: tipc node to be dumped
2471  * @more: dump more?
2472  *        - false: dump only tipc node data
2473  *        - true: dump node link data as well
2474  * @buf: returned buffer of dump data in format
2475  */
2476 int tipc_node_dump(struct tipc_node *n, bool more, char *buf)
2477 {
2478 	int i = 0;
2479 	size_t sz = (more) ? NODE_LMAX : NODE_LMIN;
2480 
2481 	if (!n) {
2482 		i += scnprintf(buf, sz, "node data: (null)\n");
2483 		return i;
2484 	}
2485 
2486 	i += scnprintf(buf, sz, "node data: %x", n->addr);
2487 	i += scnprintf(buf + i, sz - i, " %x", n->state);
2488 	i += scnprintf(buf + i, sz - i, " %d", n->active_links[0]);
2489 	i += scnprintf(buf + i, sz - i, " %d", n->active_links[1]);
2490 	i += scnprintf(buf + i, sz - i, " %x", n->action_flags);
2491 	i += scnprintf(buf + i, sz - i, " %u", n->failover_sent);
2492 	i += scnprintf(buf + i, sz - i, " %u", n->sync_point);
2493 	i += scnprintf(buf + i, sz - i, " %d", n->link_cnt);
2494 	i += scnprintf(buf + i, sz - i, " %u", n->working_links);
2495 	i += scnprintf(buf + i, sz - i, " %x", n->capabilities);
2496 	i += scnprintf(buf + i, sz - i, " %lu\n", n->keepalive_intv);
2497 
2498 	if (!more)
2499 		return i;
2500 
2501 	i += scnprintf(buf + i, sz - i, "link_entry[0]:\n");
2502 	i += scnprintf(buf + i, sz - i, " mtu: %u\n", n->links[0].mtu);
2503 	i += scnprintf(buf + i, sz - i, " media: ");
2504 	i += tipc_media_addr_printf(buf + i, sz - i, &n->links[0].maddr);
2505 	i += scnprintf(buf + i, sz - i, "\n");
2506 	i += tipc_link_dump(n->links[0].link, TIPC_DUMP_NONE, buf + i);
2507 	i += scnprintf(buf + i, sz - i, " inputq: ");
2508 	i += tipc_list_dump(&n->links[0].inputq, false, buf + i);
2509 
2510 	i += scnprintf(buf + i, sz - i, "link_entry[1]:\n");
2511 	i += scnprintf(buf + i, sz - i, " mtu: %u\n", n->links[1].mtu);
2512 	i += scnprintf(buf + i, sz - i, " media: ");
2513 	i += tipc_media_addr_printf(buf + i, sz - i, &n->links[1].maddr);
2514 	i += scnprintf(buf + i, sz - i, "\n");
2515 	i += tipc_link_dump(n->links[1].link, TIPC_DUMP_NONE, buf + i);
2516 	i += scnprintf(buf + i, sz - i, " inputq: ");
2517 	i += tipc_list_dump(&n->links[1].inputq, false, buf + i);
2518 
2519 	i += scnprintf(buf + i, sz - i, "bclink:\n ");
2520 	i += tipc_link_dump(n->bc_entry.link, TIPC_DUMP_NONE, buf + i);
2521 
2522 	return i;
2523 }
2524