xref: /openbmc/linux/net/tipc/bearer.c (revision feac8c8b)
1 /*
2  * net/tipc/bearer.c: TIPC bearer code
3  *
4  * Copyright (c) 1996-2006, 2013-2016, Ericsson AB
5  * Copyright (c) 2004-2006, 2010-2013, 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 <net/sock.h>
38 #include "core.h"
39 #include "bearer.h"
40 #include "link.h"
41 #include "discover.h"
42 #include "monitor.h"
43 #include "bcast.h"
44 #include "netlink.h"
45 #include "udp_media.h"
46 
47 #define MAX_ADDR_STR 60
48 
49 static struct tipc_media * const media_info_array[] = {
50 	&eth_media_info,
51 #ifdef CONFIG_TIPC_MEDIA_IB
52 	&ib_media_info,
53 #endif
54 #ifdef CONFIG_TIPC_MEDIA_UDP
55 	&udp_media_info,
56 #endif
57 	NULL
58 };
59 
60 static struct tipc_bearer *bearer_get(struct net *net, int bearer_id)
61 {
62 	struct tipc_net *tn = tipc_net(net);
63 
64 	return rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
65 }
66 
67 static void bearer_disable(struct net *net, struct tipc_bearer *b);
68 static int tipc_l2_rcv_msg(struct sk_buff *skb, struct net_device *dev,
69 			   struct packet_type *pt, struct net_device *orig_dev);
70 
71 /**
72  * tipc_media_find - locates specified media object by name
73  */
74 struct tipc_media *tipc_media_find(const char *name)
75 {
76 	u32 i;
77 
78 	for (i = 0; media_info_array[i] != NULL; i++) {
79 		if (!strcmp(media_info_array[i]->name, name))
80 			break;
81 	}
82 	return media_info_array[i];
83 }
84 
85 /**
86  * media_find_id - locates specified media object by type identifier
87  */
88 static struct tipc_media *media_find_id(u8 type)
89 {
90 	u32 i;
91 
92 	for (i = 0; media_info_array[i] != NULL; i++) {
93 		if (media_info_array[i]->type_id == type)
94 			break;
95 	}
96 	return media_info_array[i];
97 }
98 
99 /**
100  * tipc_media_addr_printf - record media address in print buffer
101  */
102 void tipc_media_addr_printf(char *buf, int len, struct tipc_media_addr *a)
103 {
104 	char addr_str[MAX_ADDR_STR];
105 	struct tipc_media *m;
106 	int ret;
107 
108 	m = media_find_id(a->media_id);
109 
110 	if (m && !m->addr2str(a, addr_str, sizeof(addr_str)))
111 		ret = scnprintf(buf, len, "%s(%s)", m->name, addr_str);
112 	else {
113 		u32 i;
114 
115 		ret = scnprintf(buf, len, "UNKNOWN(%u)", a->media_id);
116 		for (i = 0; i < sizeof(a->value); i++)
117 			ret += scnprintf(buf - ret, len + ret,
118 					    "-%02x", a->value[i]);
119 	}
120 }
121 
122 /**
123  * bearer_name_validate - validate & (optionally) deconstruct bearer name
124  * @name: ptr to bearer name string
125  * @name_parts: ptr to area for bearer name components (or NULL if not needed)
126  *
127  * Returns 1 if bearer name is valid, otherwise 0.
128  */
129 static int bearer_name_validate(const char *name,
130 				struct tipc_bearer_names *name_parts)
131 {
132 	char name_copy[TIPC_MAX_BEARER_NAME];
133 	char *media_name;
134 	char *if_name;
135 	u32 media_len;
136 	u32 if_len;
137 
138 	/* copy bearer name & ensure length is OK */
139 	name_copy[TIPC_MAX_BEARER_NAME - 1] = 0;
140 	/* need above in case non-Posix strncpy() doesn't pad with nulls */
141 	strncpy(name_copy, name, TIPC_MAX_BEARER_NAME);
142 	if (name_copy[TIPC_MAX_BEARER_NAME - 1] != 0)
143 		return 0;
144 
145 	/* ensure all component parts of bearer name are present */
146 	media_name = name_copy;
147 	if_name = strchr(media_name, ':');
148 	if (if_name == NULL)
149 		return 0;
150 	*(if_name++) = 0;
151 	media_len = if_name - media_name;
152 	if_len = strlen(if_name) + 1;
153 
154 	/* validate component parts of bearer name */
155 	if ((media_len <= 1) || (media_len > TIPC_MAX_MEDIA_NAME) ||
156 	    (if_len <= 1) || (if_len > TIPC_MAX_IF_NAME))
157 		return 0;
158 
159 	/* return bearer name components, if necessary */
160 	if (name_parts) {
161 		strcpy(name_parts->media_name, media_name);
162 		strcpy(name_parts->if_name, if_name);
163 	}
164 	return 1;
165 }
166 
167 /**
168  * tipc_bearer_find - locates bearer object with matching bearer name
169  */
170 struct tipc_bearer *tipc_bearer_find(struct net *net, const char *name)
171 {
172 	struct tipc_net *tn = net_generic(net, tipc_net_id);
173 	struct tipc_bearer *b;
174 	u32 i;
175 
176 	for (i = 0; i < MAX_BEARERS; i++) {
177 		b = rtnl_dereference(tn->bearer_list[i]);
178 		if (b && (!strcmp(b->name, name)))
179 			return b;
180 	}
181 	return NULL;
182 }
183 
184 /*     tipc_bearer_get_name - get the bearer name from its id.
185  *     @net: network namespace
186  *     @name: a pointer to the buffer where the name will be stored.
187  *     @bearer_id: the id to get the name from.
188  */
189 int tipc_bearer_get_name(struct net *net, char *name, u32 bearer_id)
190 {
191 	struct tipc_net *tn = tipc_net(net);
192 	struct tipc_bearer *b;
193 
194 	if (bearer_id >= MAX_BEARERS)
195 		return -EINVAL;
196 
197 	b = rtnl_dereference(tn->bearer_list[bearer_id]);
198 	if (!b)
199 		return -EINVAL;
200 
201 	strcpy(name, b->name);
202 	return 0;
203 }
204 
205 void tipc_bearer_add_dest(struct net *net, u32 bearer_id, u32 dest)
206 {
207 	struct tipc_net *tn = net_generic(net, tipc_net_id);
208 	struct tipc_bearer *b;
209 
210 	rcu_read_lock();
211 	b = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
212 	if (b)
213 		tipc_disc_add_dest(b->link_req);
214 	rcu_read_unlock();
215 }
216 
217 void tipc_bearer_remove_dest(struct net *net, u32 bearer_id, u32 dest)
218 {
219 	struct tipc_net *tn = net_generic(net, tipc_net_id);
220 	struct tipc_bearer *b;
221 
222 	rcu_read_lock();
223 	b = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
224 	if (b)
225 		tipc_disc_remove_dest(b->link_req);
226 	rcu_read_unlock();
227 }
228 
229 /**
230  * tipc_enable_bearer - enable bearer with the given name
231  */
232 static int tipc_enable_bearer(struct net *net, const char *name,
233 			      u32 disc_domain, u32 priority,
234 			      struct nlattr *attr[])
235 {
236 	struct tipc_net *tn = net_generic(net, tipc_net_id);
237 	struct tipc_bearer *b;
238 	struct tipc_media *m;
239 	struct tipc_bearer_names b_names;
240 	struct sk_buff *skb;
241 	char addr_string[16];
242 	u32 bearer_id;
243 	u32 with_this_prio;
244 	u32 i;
245 	int res = -EINVAL;
246 
247 	if (!tn->own_addr) {
248 		pr_warn("Bearer <%s> rejected, not supported in standalone mode\n",
249 			name);
250 		return -ENOPROTOOPT;
251 	}
252 	if (!bearer_name_validate(name, &b_names)) {
253 		pr_warn("Bearer <%s> rejected, illegal name\n", name);
254 		return -EINVAL;
255 	}
256 	if (tipc_addr_domain_valid(disc_domain) &&
257 	    (disc_domain != tn->own_addr)) {
258 		if (tipc_in_scope(disc_domain, tn->own_addr)) {
259 			disc_domain = tn->own_addr & TIPC_ZONE_CLUSTER_MASK;
260 			res = 0;   /* accept any node in own cluster */
261 		} else if (in_own_cluster_exact(net, disc_domain))
262 			res = 0;   /* accept specified node in own cluster */
263 	}
264 	if (res) {
265 		pr_warn("Bearer <%s> rejected, illegal discovery domain\n",
266 			name);
267 		return -EINVAL;
268 	}
269 	if ((priority > TIPC_MAX_LINK_PRI) &&
270 	    (priority != TIPC_MEDIA_LINK_PRI)) {
271 		pr_warn("Bearer <%s> rejected, illegal priority\n", name);
272 		return -EINVAL;
273 	}
274 
275 	m = tipc_media_find(b_names.media_name);
276 	if (!m) {
277 		pr_warn("Bearer <%s> rejected, media <%s> not registered\n",
278 			name, b_names.media_name);
279 		return -EINVAL;
280 	}
281 
282 	if (priority == TIPC_MEDIA_LINK_PRI)
283 		priority = m->priority;
284 
285 restart:
286 	bearer_id = MAX_BEARERS;
287 	with_this_prio = 1;
288 	for (i = MAX_BEARERS; i-- != 0; ) {
289 		b = rtnl_dereference(tn->bearer_list[i]);
290 		if (!b) {
291 			bearer_id = i;
292 			continue;
293 		}
294 		if (!strcmp(name, b->name)) {
295 			pr_warn("Bearer <%s> rejected, already enabled\n",
296 				name);
297 			return -EINVAL;
298 		}
299 		if ((b->priority == priority) &&
300 		    (++with_this_prio > 2)) {
301 			if (priority-- == 0) {
302 				pr_warn("Bearer <%s> rejected, duplicate priority\n",
303 					name);
304 				return -EINVAL;
305 			}
306 			pr_warn("Bearer <%s> priority adjustment required %u->%u\n",
307 				name, priority + 1, priority);
308 			goto restart;
309 		}
310 	}
311 	if (bearer_id >= MAX_BEARERS) {
312 		pr_warn("Bearer <%s> rejected, bearer limit reached (%u)\n",
313 			name, MAX_BEARERS);
314 		return -EINVAL;
315 	}
316 
317 	b = kzalloc(sizeof(*b), GFP_ATOMIC);
318 	if (!b)
319 		return -ENOMEM;
320 
321 	strcpy(b->name, name);
322 	b->media = m;
323 	res = m->enable_media(net, b, attr);
324 	if (res) {
325 		pr_warn("Bearer <%s> rejected, enable failure (%d)\n",
326 			name, -res);
327 		kfree(b);
328 		return -EINVAL;
329 	}
330 
331 	b->identity = bearer_id;
332 	b->tolerance = m->tolerance;
333 	b->window = m->window;
334 	b->domain = disc_domain;
335 	b->net_plane = bearer_id + 'A';
336 	b->priority = priority;
337 	test_and_set_bit_lock(0, &b->up);
338 
339 	res = tipc_disc_create(net, b, &b->bcast_addr, &skb);
340 	if (res) {
341 		bearer_disable(net, b);
342 		pr_warn("Bearer <%s> rejected, discovery object creation failed\n",
343 			name);
344 		return -EINVAL;
345 	}
346 
347 	rcu_assign_pointer(tn->bearer_list[bearer_id], b);
348 	if (skb)
349 		tipc_bearer_xmit_skb(net, bearer_id, skb, &b->bcast_addr);
350 
351 	if (tipc_mon_create(net, bearer_id)) {
352 		bearer_disable(net, b);
353 		return -ENOMEM;
354 	}
355 
356 	pr_info("Enabled bearer <%s>, discovery domain %s, priority %u\n",
357 		name,
358 		tipc_addr_string_fill(addr_string, disc_domain), priority);
359 	return res;
360 }
361 
362 /**
363  * tipc_reset_bearer - Reset all links established over this bearer
364  */
365 static int tipc_reset_bearer(struct net *net, struct tipc_bearer *b)
366 {
367 	pr_info("Resetting bearer <%s>\n", b->name);
368 	tipc_node_delete_links(net, b->identity);
369 	tipc_disc_reset(net, b);
370 	return 0;
371 }
372 
373 /**
374  * bearer_disable
375  *
376  * Note: This routine assumes caller holds RTNL lock.
377  */
378 static void bearer_disable(struct net *net, struct tipc_bearer *b)
379 {
380 	struct tipc_net *tn = tipc_net(net);
381 	int bearer_id = b->identity;
382 
383 	pr_info("Disabling bearer <%s>\n", b->name);
384 	clear_bit_unlock(0, &b->up);
385 	tipc_node_delete_links(net, bearer_id);
386 	b->media->disable_media(b);
387 	RCU_INIT_POINTER(b->media_ptr, NULL);
388 	if (b->link_req)
389 		tipc_disc_delete(b->link_req);
390 	RCU_INIT_POINTER(tn->bearer_list[bearer_id], NULL);
391 	kfree_rcu(b, rcu);
392 	tipc_mon_delete(net, bearer_id);
393 }
394 
395 int tipc_enable_l2_media(struct net *net, struct tipc_bearer *b,
396 			 struct nlattr *attr[])
397 {
398 	struct net_device *dev;
399 	char *driver_name = strchr((const char *)b->name, ':') + 1;
400 
401 	/* Find device with specified name */
402 	dev = dev_get_by_name(net, driver_name);
403 	if (!dev)
404 		return -ENODEV;
405 	if (tipc_mtu_bad(dev, 0)) {
406 		dev_put(dev);
407 		return -EINVAL;
408 	}
409 
410 	/* Associate TIPC bearer with L2 bearer */
411 	rcu_assign_pointer(b->media_ptr, dev);
412 	b->pt.dev = dev;
413 	b->pt.type = htons(ETH_P_TIPC);
414 	b->pt.func = tipc_l2_rcv_msg;
415 	dev_add_pack(&b->pt);
416 	memset(&b->bcast_addr, 0, sizeof(b->bcast_addr));
417 	memcpy(b->bcast_addr.value, dev->broadcast, b->media->hwaddr_len);
418 	b->bcast_addr.media_id = b->media->type_id;
419 	b->bcast_addr.broadcast = TIPC_BROADCAST_SUPPORT;
420 	b->mtu = dev->mtu;
421 	b->media->raw2addr(b, &b->addr, (char *)dev->dev_addr);
422 	rcu_assign_pointer(dev->tipc_ptr, b);
423 	return 0;
424 }
425 
426 /* tipc_disable_l2_media - detach TIPC bearer from an L2 interface
427  *
428  * Mark L2 bearer as inactive so that incoming buffers are thrown away
429  */
430 void tipc_disable_l2_media(struct tipc_bearer *b)
431 {
432 	struct net_device *dev;
433 
434 	dev = (struct net_device *)rtnl_dereference(b->media_ptr);
435 	dev_remove_pack(&b->pt);
436 	RCU_INIT_POINTER(dev->tipc_ptr, NULL);
437 	synchronize_net();
438 	dev_put(dev);
439 }
440 
441 /**
442  * tipc_l2_send_msg - send a TIPC packet out over an L2 interface
443  * @skb: the packet to be sent
444  * @b: the bearer through which the packet is to be sent
445  * @dest: peer destination address
446  */
447 int tipc_l2_send_msg(struct net *net, struct sk_buff *skb,
448 		     struct tipc_bearer *b, struct tipc_media_addr *dest)
449 {
450 	struct net_device *dev;
451 	int delta;
452 
453 	dev = (struct net_device *)rcu_dereference_rtnl(b->media_ptr);
454 	if (!dev)
455 		return 0;
456 
457 	delta = SKB_DATA_ALIGN(dev->hard_header_len - skb_headroom(skb));
458 	if ((delta > 0) && pskb_expand_head(skb, delta, 0, GFP_ATOMIC)) {
459 		kfree_skb(skb);
460 		return 0;
461 	}
462 	skb_reset_network_header(skb);
463 	skb->dev = dev;
464 	skb->protocol = htons(ETH_P_TIPC);
465 	dev_hard_header(skb, dev, ETH_P_TIPC, dest->value,
466 			dev->dev_addr, skb->len);
467 	dev_queue_xmit(skb);
468 	return 0;
469 }
470 
471 bool tipc_bearer_bcast_support(struct net *net, u32 bearer_id)
472 {
473 	bool supp = false;
474 	struct tipc_bearer *b;
475 
476 	rcu_read_lock();
477 	b = bearer_get(net, bearer_id);
478 	if (b)
479 		supp = (b->bcast_addr.broadcast == TIPC_BROADCAST_SUPPORT);
480 	rcu_read_unlock();
481 	return supp;
482 }
483 
484 int tipc_bearer_mtu(struct net *net, u32 bearer_id)
485 {
486 	int mtu = 0;
487 	struct tipc_bearer *b;
488 
489 	rcu_read_lock();
490 	b = rcu_dereference_rtnl(tipc_net(net)->bearer_list[bearer_id]);
491 	if (b)
492 		mtu = b->mtu;
493 	rcu_read_unlock();
494 	return mtu;
495 }
496 
497 /* tipc_bearer_xmit_skb - sends buffer to destination over bearer
498  */
499 void tipc_bearer_xmit_skb(struct net *net, u32 bearer_id,
500 			  struct sk_buff *skb,
501 			  struct tipc_media_addr *dest)
502 {
503 	struct tipc_msg *hdr = buf_msg(skb);
504 	struct tipc_bearer *b;
505 
506 	rcu_read_lock();
507 	b = bearer_get(net, bearer_id);
508 	if (likely(b && (test_bit(0, &b->up) || msg_is_reset(hdr))))
509 		b->media->send_msg(net, skb, b, dest);
510 	else
511 		kfree_skb(skb);
512 	rcu_read_unlock();
513 }
514 
515 /* tipc_bearer_xmit() -send buffer to destination over bearer
516  */
517 void tipc_bearer_xmit(struct net *net, u32 bearer_id,
518 		      struct sk_buff_head *xmitq,
519 		      struct tipc_media_addr *dst)
520 {
521 	struct tipc_bearer *b;
522 	struct sk_buff *skb, *tmp;
523 
524 	if (skb_queue_empty(xmitq))
525 		return;
526 
527 	rcu_read_lock();
528 	b = bearer_get(net, bearer_id);
529 	if (unlikely(!b))
530 		__skb_queue_purge(xmitq);
531 	skb_queue_walk_safe(xmitq, skb, tmp) {
532 		__skb_dequeue(xmitq);
533 		if (likely(test_bit(0, &b->up) || msg_is_reset(buf_msg(skb))))
534 			b->media->send_msg(net, skb, b, dst);
535 		else
536 			kfree_skb(skb);
537 	}
538 	rcu_read_unlock();
539 }
540 
541 /* tipc_bearer_bc_xmit() - broadcast buffers to all destinations
542  */
543 void tipc_bearer_bc_xmit(struct net *net, u32 bearer_id,
544 			 struct sk_buff_head *xmitq)
545 {
546 	struct tipc_net *tn = tipc_net(net);
547 	int net_id = tn->net_id;
548 	struct tipc_bearer *b;
549 	struct sk_buff *skb, *tmp;
550 	struct tipc_msg *hdr;
551 
552 	rcu_read_lock();
553 	b = bearer_get(net, bearer_id);
554 	if (unlikely(!b || !test_bit(0, &b->up)))
555 		__skb_queue_purge(xmitq);
556 	skb_queue_walk_safe(xmitq, skb, tmp) {
557 		hdr = buf_msg(skb);
558 		msg_set_non_seq(hdr, 1);
559 		msg_set_mc_netid(hdr, net_id);
560 		__skb_dequeue(xmitq);
561 		b->media->send_msg(net, skb, b, &b->bcast_addr);
562 	}
563 	rcu_read_unlock();
564 }
565 
566 /**
567  * tipc_l2_rcv_msg - handle incoming TIPC message from an interface
568  * @buf: the received packet
569  * @dev: the net device that the packet was received on
570  * @pt: the packet_type structure which was used to register this handler
571  * @orig_dev: the original receive net device in case the device is a bond
572  *
573  * Accept only packets explicitly sent to this node, or broadcast packets;
574  * ignores packets sent using interface multicast, and traffic sent to other
575  * nodes (which can happen if interface is running in promiscuous mode).
576  */
577 static int tipc_l2_rcv_msg(struct sk_buff *skb, struct net_device *dev,
578 			   struct packet_type *pt, struct net_device *orig_dev)
579 {
580 	struct tipc_bearer *b;
581 
582 	rcu_read_lock();
583 	b = rcu_dereference_rtnl(dev->tipc_ptr) ?:
584 		rcu_dereference_rtnl(orig_dev->tipc_ptr);
585 	if (likely(b && test_bit(0, &b->up) &&
586 		   (skb->pkt_type <= PACKET_MULTICAST))) {
587 		skb->next = NULL;
588 		tipc_rcv(dev_net(b->pt.dev), skb, b);
589 		rcu_read_unlock();
590 		return NET_RX_SUCCESS;
591 	}
592 	rcu_read_unlock();
593 	kfree_skb(skb);
594 	return NET_RX_DROP;
595 }
596 
597 /**
598  * tipc_l2_device_event - handle device events from network device
599  * @nb: the context of the notification
600  * @evt: the type of event
601  * @ptr: the net device that the event was on
602  *
603  * This function is called by the Ethernet driver in case of link
604  * change event.
605  */
606 static int tipc_l2_device_event(struct notifier_block *nb, unsigned long evt,
607 				void *ptr)
608 {
609 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
610 	struct net *net = dev_net(dev);
611 	struct tipc_bearer *b;
612 
613 	b = rtnl_dereference(dev->tipc_ptr);
614 	if (!b)
615 		return NOTIFY_DONE;
616 
617 	switch (evt) {
618 	case NETDEV_CHANGE:
619 		if (netif_carrier_ok(dev))
620 			break;
621 	case NETDEV_UP:
622 		test_and_set_bit_lock(0, &b->up);
623 		break;
624 	case NETDEV_GOING_DOWN:
625 		clear_bit_unlock(0, &b->up);
626 		tipc_reset_bearer(net, b);
627 		break;
628 	case NETDEV_CHANGEMTU:
629 		if (tipc_mtu_bad(dev, 0)) {
630 			bearer_disable(net, b);
631 			break;
632 		}
633 		b->mtu = dev->mtu;
634 		tipc_reset_bearer(net, b);
635 		break;
636 	case NETDEV_CHANGEADDR:
637 		b->media->raw2addr(b, &b->addr,
638 				   (char *)dev->dev_addr);
639 		tipc_reset_bearer(net, b);
640 		break;
641 	case NETDEV_UNREGISTER:
642 	case NETDEV_CHANGENAME:
643 		bearer_disable(net, b);
644 		break;
645 	}
646 	return NOTIFY_OK;
647 }
648 
649 static struct notifier_block notifier = {
650 	.notifier_call  = tipc_l2_device_event,
651 	.priority	= 0,
652 };
653 
654 int tipc_bearer_setup(void)
655 {
656 	return register_netdevice_notifier(&notifier);
657 }
658 
659 void tipc_bearer_cleanup(void)
660 {
661 	unregister_netdevice_notifier(&notifier);
662 }
663 
664 void tipc_bearer_stop(struct net *net)
665 {
666 	struct tipc_net *tn = net_generic(net, tipc_net_id);
667 	struct tipc_bearer *b;
668 	u32 i;
669 
670 	for (i = 0; i < MAX_BEARERS; i++) {
671 		b = rtnl_dereference(tn->bearer_list[i]);
672 		if (b) {
673 			bearer_disable(net, b);
674 			tn->bearer_list[i] = NULL;
675 		}
676 	}
677 }
678 
679 /* Caller should hold rtnl_lock to protect the bearer */
680 static int __tipc_nl_add_bearer(struct tipc_nl_msg *msg,
681 				struct tipc_bearer *bearer, int nlflags)
682 {
683 	void *hdr;
684 	struct nlattr *attrs;
685 	struct nlattr *prop;
686 
687 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
688 			  nlflags, TIPC_NL_BEARER_GET);
689 	if (!hdr)
690 		return -EMSGSIZE;
691 
692 	attrs = nla_nest_start(msg->skb, TIPC_NLA_BEARER);
693 	if (!attrs)
694 		goto msg_full;
695 
696 	if (nla_put_string(msg->skb, TIPC_NLA_BEARER_NAME, bearer->name))
697 		goto attr_msg_full;
698 
699 	prop = nla_nest_start(msg->skb, TIPC_NLA_BEARER_PROP);
700 	if (!prop)
701 		goto prop_msg_full;
702 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, bearer->priority))
703 		goto prop_msg_full;
704 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, bearer->tolerance))
705 		goto prop_msg_full;
706 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bearer->window))
707 		goto prop_msg_full;
708 
709 	nla_nest_end(msg->skb, prop);
710 
711 #ifdef CONFIG_TIPC_MEDIA_UDP
712 	if (bearer->media->type_id == TIPC_MEDIA_TYPE_UDP) {
713 		if (tipc_udp_nl_add_bearer_data(msg, bearer))
714 			goto attr_msg_full;
715 	}
716 #endif
717 
718 	nla_nest_end(msg->skb, attrs);
719 	genlmsg_end(msg->skb, hdr);
720 
721 	return 0;
722 
723 prop_msg_full:
724 	nla_nest_cancel(msg->skb, prop);
725 attr_msg_full:
726 	nla_nest_cancel(msg->skb, attrs);
727 msg_full:
728 	genlmsg_cancel(msg->skb, hdr);
729 
730 	return -EMSGSIZE;
731 }
732 
733 int tipc_nl_bearer_dump(struct sk_buff *skb, struct netlink_callback *cb)
734 {
735 	int err;
736 	int i = cb->args[0];
737 	struct tipc_bearer *bearer;
738 	struct tipc_nl_msg msg;
739 	struct net *net = sock_net(skb->sk);
740 	struct tipc_net *tn = net_generic(net, tipc_net_id);
741 
742 	if (i == MAX_BEARERS)
743 		return 0;
744 
745 	msg.skb = skb;
746 	msg.portid = NETLINK_CB(cb->skb).portid;
747 	msg.seq = cb->nlh->nlmsg_seq;
748 
749 	rtnl_lock();
750 	for (i = 0; i < MAX_BEARERS; i++) {
751 		bearer = rtnl_dereference(tn->bearer_list[i]);
752 		if (!bearer)
753 			continue;
754 
755 		err = __tipc_nl_add_bearer(&msg, bearer, NLM_F_MULTI);
756 		if (err)
757 			break;
758 	}
759 	rtnl_unlock();
760 
761 	cb->args[0] = i;
762 	return skb->len;
763 }
764 
765 int tipc_nl_bearer_get(struct sk_buff *skb, struct genl_info *info)
766 {
767 	int err;
768 	char *name;
769 	struct sk_buff *rep;
770 	struct tipc_bearer *bearer;
771 	struct tipc_nl_msg msg;
772 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
773 	struct net *net = genl_info_net(info);
774 
775 	if (!info->attrs[TIPC_NLA_BEARER])
776 		return -EINVAL;
777 
778 	err = nla_parse_nested(attrs, TIPC_NLA_BEARER_MAX,
779 			       info->attrs[TIPC_NLA_BEARER],
780 			       tipc_nl_bearer_policy, info->extack);
781 	if (err)
782 		return err;
783 
784 	if (!attrs[TIPC_NLA_BEARER_NAME])
785 		return -EINVAL;
786 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
787 
788 	rep = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
789 	if (!rep)
790 		return -ENOMEM;
791 
792 	msg.skb = rep;
793 	msg.portid = info->snd_portid;
794 	msg.seq = info->snd_seq;
795 
796 	rtnl_lock();
797 	bearer = tipc_bearer_find(net, name);
798 	if (!bearer) {
799 		err = -EINVAL;
800 		goto err_out;
801 	}
802 
803 	err = __tipc_nl_add_bearer(&msg, bearer, 0);
804 	if (err)
805 		goto err_out;
806 	rtnl_unlock();
807 
808 	return genlmsg_reply(rep, info);
809 err_out:
810 	rtnl_unlock();
811 	nlmsg_free(rep);
812 
813 	return err;
814 }
815 
816 int __tipc_nl_bearer_disable(struct sk_buff *skb, struct genl_info *info)
817 {
818 	int err;
819 	char *name;
820 	struct tipc_bearer *bearer;
821 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
822 	struct net *net = sock_net(skb->sk);
823 
824 	if (!info->attrs[TIPC_NLA_BEARER])
825 		return -EINVAL;
826 
827 	err = nla_parse_nested(attrs, TIPC_NLA_BEARER_MAX,
828 			       info->attrs[TIPC_NLA_BEARER],
829 			       tipc_nl_bearer_policy, info->extack);
830 	if (err)
831 		return err;
832 
833 	if (!attrs[TIPC_NLA_BEARER_NAME])
834 		return -EINVAL;
835 
836 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
837 
838 	bearer = tipc_bearer_find(net, name);
839 	if (!bearer)
840 		return -EINVAL;
841 
842 	bearer_disable(net, bearer);
843 
844 	return 0;
845 }
846 
847 int tipc_nl_bearer_disable(struct sk_buff *skb, struct genl_info *info)
848 {
849 	int err;
850 
851 	rtnl_lock();
852 	err = __tipc_nl_bearer_disable(skb, info);
853 	rtnl_unlock();
854 
855 	return err;
856 }
857 
858 int __tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info)
859 {
860 	int err;
861 	char *bearer;
862 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
863 	struct net *net = sock_net(skb->sk);
864 	struct tipc_net *tn = net_generic(net, tipc_net_id);
865 	u32 domain;
866 	u32 prio;
867 
868 	prio = TIPC_MEDIA_LINK_PRI;
869 	domain = tn->own_addr & TIPC_ZONE_CLUSTER_MASK;
870 
871 	if (!info->attrs[TIPC_NLA_BEARER])
872 		return -EINVAL;
873 
874 	err = nla_parse_nested(attrs, TIPC_NLA_BEARER_MAX,
875 			       info->attrs[TIPC_NLA_BEARER],
876 			       tipc_nl_bearer_policy, info->extack);
877 	if (err)
878 		return err;
879 
880 	if (!attrs[TIPC_NLA_BEARER_NAME])
881 		return -EINVAL;
882 
883 	bearer = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
884 
885 	if (attrs[TIPC_NLA_BEARER_DOMAIN])
886 		domain = nla_get_u32(attrs[TIPC_NLA_BEARER_DOMAIN]);
887 
888 	if (attrs[TIPC_NLA_BEARER_PROP]) {
889 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
890 
891 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_BEARER_PROP],
892 					      props);
893 		if (err)
894 			return err;
895 
896 		if (props[TIPC_NLA_PROP_PRIO])
897 			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
898 	}
899 
900 	return tipc_enable_bearer(net, bearer, domain, prio, attrs);
901 }
902 
903 int tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info)
904 {
905 	int err;
906 
907 	rtnl_lock();
908 	err = __tipc_nl_bearer_enable(skb, info);
909 	rtnl_unlock();
910 
911 	return err;
912 }
913 
914 int tipc_nl_bearer_add(struct sk_buff *skb, struct genl_info *info)
915 {
916 	int err;
917 	char *name;
918 	struct tipc_bearer *b;
919 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
920 	struct net *net = sock_net(skb->sk);
921 
922 	if (!info->attrs[TIPC_NLA_BEARER])
923 		return -EINVAL;
924 
925 	err = nla_parse_nested(attrs, TIPC_NLA_BEARER_MAX,
926 			       info->attrs[TIPC_NLA_BEARER],
927 			       tipc_nl_bearer_policy, info->extack);
928 	if (err)
929 		return err;
930 
931 	if (!attrs[TIPC_NLA_BEARER_NAME])
932 		return -EINVAL;
933 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
934 
935 	rtnl_lock();
936 	b = tipc_bearer_find(net, name);
937 	if (!b) {
938 		rtnl_unlock();
939 		return -EINVAL;
940 	}
941 
942 #ifdef CONFIG_TIPC_MEDIA_UDP
943 	if (attrs[TIPC_NLA_BEARER_UDP_OPTS]) {
944 		err = tipc_udp_nl_bearer_add(b,
945 					     attrs[TIPC_NLA_BEARER_UDP_OPTS]);
946 		if (err) {
947 			rtnl_unlock();
948 			return err;
949 		}
950 	}
951 #endif
952 	rtnl_unlock();
953 
954 	return 0;
955 }
956 
957 int __tipc_nl_bearer_set(struct sk_buff *skb, struct genl_info *info)
958 {
959 	int err;
960 	char *name;
961 	struct tipc_bearer *b;
962 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
963 	struct net *net = sock_net(skb->sk);
964 
965 	if (!info->attrs[TIPC_NLA_BEARER])
966 		return -EINVAL;
967 
968 	err = nla_parse_nested(attrs, TIPC_NLA_BEARER_MAX,
969 			       info->attrs[TIPC_NLA_BEARER],
970 			       tipc_nl_bearer_policy, info->extack);
971 	if (err)
972 		return err;
973 
974 	if (!attrs[TIPC_NLA_BEARER_NAME])
975 		return -EINVAL;
976 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
977 
978 	b = tipc_bearer_find(net, name);
979 	if (!b)
980 		return -EINVAL;
981 
982 	if (attrs[TIPC_NLA_BEARER_PROP]) {
983 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
984 
985 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_BEARER_PROP],
986 					      props);
987 		if (err)
988 			return err;
989 
990 		if (props[TIPC_NLA_PROP_TOL])
991 			b->tolerance = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
992 		if (props[TIPC_NLA_PROP_PRIO])
993 			b->priority = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
994 		if (props[TIPC_NLA_PROP_WIN])
995 			b->window = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
996 	}
997 
998 	return 0;
999 }
1000 
1001 int tipc_nl_bearer_set(struct sk_buff *skb, struct genl_info *info)
1002 {
1003 	int err;
1004 
1005 	rtnl_lock();
1006 	err = __tipc_nl_bearer_set(skb, info);
1007 	rtnl_unlock();
1008 
1009 	return err;
1010 }
1011 
1012 static int __tipc_nl_add_media(struct tipc_nl_msg *msg,
1013 			       struct tipc_media *media, int nlflags)
1014 {
1015 	void *hdr;
1016 	struct nlattr *attrs;
1017 	struct nlattr *prop;
1018 
1019 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1020 			  nlflags, TIPC_NL_MEDIA_GET);
1021 	if (!hdr)
1022 		return -EMSGSIZE;
1023 
1024 	attrs = nla_nest_start(msg->skb, TIPC_NLA_MEDIA);
1025 	if (!attrs)
1026 		goto msg_full;
1027 
1028 	if (nla_put_string(msg->skb, TIPC_NLA_MEDIA_NAME, media->name))
1029 		goto attr_msg_full;
1030 
1031 	prop = nla_nest_start(msg->skb, TIPC_NLA_MEDIA_PROP);
1032 	if (!prop)
1033 		goto prop_msg_full;
1034 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, media->priority))
1035 		goto prop_msg_full;
1036 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, media->tolerance))
1037 		goto prop_msg_full;
1038 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, media->window))
1039 		goto prop_msg_full;
1040 
1041 	nla_nest_end(msg->skb, prop);
1042 	nla_nest_end(msg->skb, attrs);
1043 	genlmsg_end(msg->skb, hdr);
1044 
1045 	return 0;
1046 
1047 prop_msg_full:
1048 	nla_nest_cancel(msg->skb, prop);
1049 attr_msg_full:
1050 	nla_nest_cancel(msg->skb, attrs);
1051 msg_full:
1052 	genlmsg_cancel(msg->skb, hdr);
1053 
1054 	return -EMSGSIZE;
1055 }
1056 
1057 int tipc_nl_media_dump(struct sk_buff *skb, struct netlink_callback *cb)
1058 {
1059 	int err;
1060 	int i = cb->args[0];
1061 	struct tipc_nl_msg msg;
1062 
1063 	if (i == MAX_MEDIA)
1064 		return 0;
1065 
1066 	msg.skb = skb;
1067 	msg.portid = NETLINK_CB(cb->skb).portid;
1068 	msg.seq = cb->nlh->nlmsg_seq;
1069 
1070 	rtnl_lock();
1071 	for (; media_info_array[i] != NULL; i++) {
1072 		err = __tipc_nl_add_media(&msg, media_info_array[i],
1073 					  NLM_F_MULTI);
1074 		if (err)
1075 			break;
1076 	}
1077 	rtnl_unlock();
1078 
1079 	cb->args[0] = i;
1080 	return skb->len;
1081 }
1082 
1083 int tipc_nl_media_get(struct sk_buff *skb, struct genl_info *info)
1084 {
1085 	int err;
1086 	char *name;
1087 	struct tipc_nl_msg msg;
1088 	struct tipc_media *media;
1089 	struct sk_buff *rep;
1090 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
1091 
1092 	if (!info->attrs[TIPC_NLA_MEDIA])
1093 		return -EINVAL;
1094 
1095 	err = nla_parse_nested(attrs, TIPC_NLA_MEDIA_MAX,
1096 			       info->attrs[TIPC_NLA_MEDIA],
1097 			       tipc_nl_media_policy, info->extack);
1098 	if (err)
1099 		return err;
1100 
1101 	if (!attrs[TIPC_NLA_MEDIA_NAME])
1102 		return -EINVAL;
1103 	name = nla_data(attrs[TIPC_NLA_MEDIA_NAME]);
1104 
1105 	rep = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
1106 	if (!rep)
1107 		return -ENOMEM;
1108 
1109 	msg.skb = rep;
1110 	msg.portid = info->snd_portid;
1111 	msg.seq = info->snd_seq;
1112 
1113 	rtnl_lock();
1114 	media = tipc_media_find(name);
1115 	if (!media) {
1116 		err = -EINVAL;
1117 		goto err_out;
1118 	}
1119 
1120 	err = __tipc_nl_add_media(&msg, media, 0);
1121 	if (err)
1122 		goto err_out;
1123 	rtnl_unlock();
1124 
1125 	return genlmsg_reply(rep, info);
1126 err_out:
1127 	rtnl_unlock();
1128 	nlmsg_free(rep);
1129 
1130 	return err;
1131 }
1132 
1133 int __tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info)
1134 {
1135 	int err;
1136 	char *name;
1137 	struct tipc_media *m;
1138 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
1139 
1140 	if (!info->attrs[TIPC_NLA_MEDIA])
1141 		return -EINVAL;
1142 
1143 	err = nla_parse_nested(attrs, TIPC_NLA_MEDIA_MAX,
1144 			       info->attrs[TIPC_NLA_MEDIA],
1145 			       tipc_nl_media_policy, info->extack);
1146 
1147 	if (!attrs[TIPC_NLA_MEDIA_NAME])
1148 		return -EINVAL;
1149 	name = nla_data(attrs[TIPC_NLA_MEDIA_NAME]);
1150 
1151 	m = tipc_media_find(name);
1152 	if (!m)
1153 		return -EINVAL;
1154 
1155 	if (attrs[TIPC_NLA_MEDIA_PROP]) {
1156 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
1157 
1158 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_MEDIA_PROP],
1159 					      props);
1160 		if (err)
1161 			return err;
1162 
1163 		if (props[TIPC_NLA_PROP_TOL])
1164 			m->tolerance = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1165 		if (props[TIPC_NLA_PROP_PRIO])
1166 			m->priority = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1167 		if (props[TIPC_NLA_PROP_WIN])
1168 			m->window = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1169 	}
1170 
1171 	return 0;
1172 }
1173 
1174 int tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info)
1175 {
1176 	int err;
1177 
1178 	rtnl_lock();
1179 	err = __tipc_nl_media_set(skb, info);
1180 	rtnl_unlock();
1181 
1182 	return err;
1183 }
1184