xref: /linux/net/tipc/bearer.c (revision d2912cb15bdda8ba4a5dd73396ad62641af2f520)
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 #include "trace.h"
47 
48 #define MAX_ADDR_STR 60
49 
50 static struct tipc_media * const media_info_array[] = {
51 	&eth_media_info,
52 #ifdef CONFIG_TIPC_MEDIA_IB
53 	&ib_media_info,
54 #endif
55 #ifdef CONFIG_TIPC_MEDIA_UDP
56 	&udp_media_info,
57 #endif
58 	NULL
59 };
60 
61 static struct tipc_bearer *bearer_get(struct net *net, int bearer_id)
62 {
63 	struct tipc_net *tn = tipc_net(net);
64 
65 	return rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
66 }
67 
68 static void bearer_disable(struct net *net, struct tipc_bearer *b);
69 static int tipc_l2_rcv_msg(struct sk_buff *skb, struct net_device *dev,
70 			   struct packet_type *pt, struct net_device *orig_dev);
71 
72 /**
73  * tipc_media_find - locates specified media object by name
74  */
75 struct tipc_media *tipc_media_find(const char *name)
76 {
77 	u32 i;
78 
79 	for (i = 0; media_info_array[i] != NULL; i++) {
80 		if (!strcmp(media_info_array[i]->name, name))
81 			break;
82 	}
83 	return media_info_array[i];
84 }
85 
86 /**
87  * media_find_id - locates specified media object by type identifier
88  */
89 static struct tipc_media *media_find_id(u8 type)
90 {
91 	u32 i;
92 
93 	for (i = 0; media_info_array[i] != NULL; i++) {
94 		if (media_info_array[i]->type_id == type)
95 			break;
96 	}
97 	return media_info_array[i];
98 }
99 
100 /**
101  * tipc_media_addr_printf - record media address in print buffer
102  */
103 int tipc_media_addr_printf(char *buf, int len, struct tipc_media_addr *a)
104 {
105 	char addr_str[MAX_ADDR_STR];
106 	struct tipc_media *m;
107 	int ret;
108 
109 	m = media_find_id(a->media_id);
110 
111 	if (m && !m->addr2str(a, addr_str, sizeof(addr_str)))
112 		ret = scnprintf(buf, len, "%s(%s)", m->name, addr_str);
113 	else {
114 		u32 i;
115 
116 		ret = scnprintf(buf, len, "UNKNOWN(%u)", a->media_id);
117 		for (i = 0; i < sizeof(a->value); i++)
118 			ret += scnprintf(buf + ret, len - ret,
119 					    "-%x", a->value[i]);
120 	}
121 	return ret;
122 }
123 
124 /**
125  * bearer_name_validate - validate & (optionally) deconstruct bearer name
126  * @name: ptr to bearer name string
127  * @name_parts: ptr to area for bearer name components (or NULL if not needed)
128  *
129  * Returns 1 if bearer name is valid, otherwise 0.
130  */
131 static int bearer_name_validate(const char *name,
132 				struct tipc_bearer_names *name_parts)
133 {
134 	char name_copy[TIPC_MAX_BEARER_NAME];
135 	char *media_name;
136 	char *if_name;
137 	u32 media_len;
138 	u32 if_len;
139 
140 	/* copy bearer name & ensure length is OK */
141 	name_copy[TIPC_MAX_BEARER_NAME - 1] = 0;
142 	/* need above in case non-Posix strncpy() doesn't pad with nulls */
143 	strncpy(name_copy, name, TIPC_MAX_BEARER_NAME);
144 	if (name_copy[TIPC_MAX_BEARER_NAME - 1] != 0)
145 		return 0;
146 
147 	/* ensure all component parts of bearer name are present */
148 	media_name = name_copy;
149 	if_name = strchr(media_name, ':');
150 	if (if_name == NULL)
151 		return 0;
152 	*(if_name++) = 0;
153 	media_len = if_name - media_name;
154 	if_len = strlen(if_name) + 1;
155 
156 	/* validate component parts of bearer name */
157 	if ((media_len <= 1) || (media_len > TIPC_MAX_MEDIA_NAME) ||
158 	    (if_len <= 1) || (if_len > TIPC_MAX_IF_NAME))
159 		return 0;
160 
161 	/* return bearer name components, if necessary */
162 	if (name_parts) {
163 		strcpy(name_parts->media_name, media_name);
164 		strcpy(name_parts->if_name, if_name);
165 	}
166 	return 1;
167 }
168 
169 /**
170  * tipc_bearer_find - locates bearer object with matching bearer name
171  */
172 struct tipc_bearer *tipc_bearer_find(struct net *net, const char *name)
173 {
174 	struct tipc_net *tn = net_generic(net, tipc_net_id);
175 	struct tipc_bearer *b;
176 	u32 i;
177 
178 	for (i = 0; i < MAX_BEARERS; i++) {
179 		b = rtnl_dereference(tn->bearer_list[i]);
180 		if (b && (!strcmp(b->name, name)))
181 			return b;
182 	}
183 	return NULL;
184 }
185 
186 /*     tipc_bearer_get_name - get the bearer name from its id.
187  *     @net: network namespace
188  *     @name: a pointer to the buffer where the name will be stored.
189  *     @bearer_id: the id to get the name from.
190  */
191 int tipc_bearer_get_name(struct net *net, char *name, u32 bearer_id)
192 {
193 	struct tipc_net *tn = tipc_net(net);
194 	struct tipc_bearer *b;
195 
196 	if (bearer_id >= MAX_BEARERS)
197 		return -EINVAL;
198 
199 	b = rtnl_dereference(tn->bearer_list[bearer_id]);
200 	if (!b)
201 		return -EINVAL;
202 
203 	strcpy(name, b->name);
204 	return 0;
205 }
206 
207 void tipc_bearer_add_dest(struct net *net, u32 bearer_id, u32 dest)
208 {
209 	struct tipc_net *tn = net_generic(net, tipc_net_id);
210 	struct tipc_bearer *b;
211 
212 	rcu_read_lock();
213 	b = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
214 	if (b)
215 		tipc_disc_add_dest(b->disc);
216 	rcu_read_unlock();
217 }
218 
219 void tipc_bearer_remove_dest(struct net *net, u32 bearer_id, u32 dest)
220 {
221 	struct tipc_net *tn = net_generic(net, tipc_net_id);
222 	struct tipc_bearer *b;
223 
224 	rcu_read_lock();
225 	b = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
226 	if (b)
227 		tipc_disc_remove_dest(b->disc);
228 	rcu_read_unlock();
229 }
230 
231 /**
232  * tipc_enable_bearer - enable bearer with the given name
233  */
234 static int tipc_enable_bearer(struct net *net, const char *name,
235 			      u32 disc_domain, u32 prio,
236 			      struct nlattr *attr[])
237 {
238 	struct tipc_net *tn = tipc_net(net);
239 	struct tipc_bearer_names b_names;
240 	int with_this_prio = 1;
241 	struct tipc_bearer *b;
242 	struct tipc_media *m;
243 	struct sk_buff *skb;
244 	int bearer_id = 0;
245 	int res = -EINVAL;
246 	char *errstr = "";
247 
248 	if (!bearer_name_validate(name, &b_names)) {
249 		errstr = "illegal name";
250 		goto rejected;
251 	}
252 
253 	if (prio > TIPC_MAX_LINK_PRI && prio != TIPC_MEDIA_LINK_PRI) {
254 		errstr = "illegal priority";
255 		goto rejected;
256 	}
257 
258 	m = tipc_media_find(b_names.media_name);
259 	if (!m) {
260 		errstr = "media not registered";
261 		goto rejected;
262 	}
263 
264 	if (prio == TIPC_MEDIA_LINK_PRI)
265 		prio = m->priority;
266 
267 	/* Check new bearer vs existing ones and find free bearer id if any */
268 	while (bearer_id < MAX_BEARERS) {
269 		b = rtnl_dereference(tn->bearer_list[bearer_id]);
270 		if (!b)
271 			break;
272 		if (!strcmp(name, b->name)) {
273 			errstr = "already enabled";
274 			goto rejected;
275 		}
276 		bearer_id++;
277 		if (b->priority != prio)
278 			continue;
279 		if (++with_this_prio <= 2)
280 			continue;
281 		pr_warn("Bearer <%s>: already 2 bearers with priority %u\n",
282 			name, prio);
283 		if (prio == TIPC_MIN_LINK_PRI) {
284 			errstr = "cannot adjust to lower";
285 			goto rejected;
286 		}
287 		pr_warn("Bearer <%s>: trying with adjusted priority\n", name);
288 		prio--;
289 		bearer_id = 0;
290 		with_this_prio = 1;
291 	}
292 
293 	if (bearer_id >= MAX_BEARERS) {
294 		errstr = "max 3 bearers permitted";
295 		goto rejected;
296 	}
297 
298 	b = kzalloc(sizeof(*b), GFP_ATOMIC);
299 	if (!b)
300 		return -ENOMEM;
301 
302 	strcpy(b->name, name);
303 	b->media = m;
304 	res = m->enable_media(net, b, attr);
305 	if (res) {
306 		kfree(b);
307 		errstr = "failed to enable media";
308 		goto rejected;
309 	}
310 
311 	b->identity = bearer_id;
312 	b->tolerance = m->tolerance;
313 	b->window = m->window;
314 	b->domain = disc_domain;
315 	b->net_plane = bearer_id + 'A';
316 	b->priority = prio;
317 	test_and_set_bit_lock(0, &b->up);
318 
319 	res = tipc_disc_create(net, b, &b->bcast_addr, &skb);
320 	if (res) {
321 		bearer_disable(net, b);
322 		errstr = "failed to create discoverer";
323 		goto rejected;
324 	}
325 
326 	rcu_assign_pointer(tn->bearer_list[bearer_id], b);
327 	if (skb)
328 		tipc_bearer_xmit_skb(net, bearer_id, skb, &b->bcast_addr);
329 
330 	if (tipc_mon_create(net, bearer_id)) {
331 		bearer_disable(net, b);
332 		return -ENOMEM;
333 	}
334 
335 	pr_info("Enabled bearer <%s>, priority %u\n", name, prio);
336 
337 	return res;
338 rejected:
339 	pr_warn("Enabling of bearer <%s> rejected, %s\n", name, errstr);
340 	return res;
341 }
342 
343 /**
344  * tipc_reset_bearer - Reset all links established over this bearer
345  */
346 static int tipc_reset_bearer(struct net *net, struct tipc_bearer *b)
347 {
348 	pr_info("Resetting bearer <%s>\n", b->name);
349 	tipc_node_delete_links(net, b->identity);
350 	tipc_disc_reset(net, b);
351 	return 0;
352 }
353 
354 /**
355  * bearer_disable
356  *
357  * Note: This routine assumes caller holds RTNL lock.
358  */
359 static void bearer_disable(struct net *net, struct tipc_bearer *b)
360 {
361 	struct tipc_net *tn = tipc_net(net);
362 	int bearer_id = b->identity;
363 
364 	pr_info("Disabling bearer <%s>\n", b->name);
365 	clear_bit_unlock(0, &b->up);
366 	tipc_node_delete_links(net, bearer_id);
367 	b->media->disable_media(b);
368 	RCU_INIT_POINTER(b->media_ptr, NULL);
369 	if (b->disc)
370 		tipc_disc_delete(b->disc);
371 	RCU_INIT_POINTER(tn->bearer_list[bearer_id], NULL);
372 	kfree_rcu(b, rcu);
373 	tipc_mon_delete(net, bearer_id);
374 }
375 
376 int tipc_enable_l2_media(struct net *net, struct tipc_bearer *b,
377 			 struct nlattr *attr[])
378 {
379 	char *dev_name = strchr((const char *)b->name, ':') + 1;
380 	int hwaddr_len = b->media->hwaddr_len;
381 	u8 node_id[NODE_ID_LEN] = {0,};
382 	struct net_device *dev;
383 
384 	/* Find device with specified name */
385 	dev = dev_get_by_name(net, dev_name);
386 	if (!dev)
387 		return -ENODEV;
388 	if (tipc_mtu_bad(dev, 0)) {
389 		dev_put(dev);
390 		return -EINVAL;
391 	}
392 
393 	/* Autoconfigure own node identity if needed */
394 	if (!tipc_own_id(net) && hwaddr_len <= NODE_ID_LEN) {
395 		memcpy(node_id, dev->dev_addr, hwaddr_len);
396 		tipc_net_init(net, node_id, 0);
397 	}
398 	if (!tipc_own_id(net)) {
399 		dev_put(dev);
400 		pr_warn("Failed to obtain node identity\n");
401 		return -EINVAL;
402 	}
403 
404 	/* Associate TIPC bearer with L2 bearer */
405 	rcu_assign_pointer(b->media_ptr, dev);
406 	b->pt.dev = dev;
407 	b->pt.type = htons(ETH_P_TIPC);
408 	b->pt.func = tipc_l2_rcv_msg;
409 	dev_add_pack(&b->pt);
410 	memset(&b->bcast_addr, 0, sizeof(b->bcast_addr));
411 	memcpy(b->bcast_addr.value, dev->broadcast, hwaddr_len);
412 	b->bcast_addr.media_id = b->media->type_id;
413 	b->bcast_addr.broadcast = TIPC_BROADCAST_SUPPORT;
414 	b->mtu = dev->mtu;
415 	b->media->raw2addr(b, &b->addr, (char *)dev->dev_addr);
416 	rcu_assign_pointer(dev->tipc_ptr, b);
417 	return 0;
418 }
419 
420 /* tipc_disable_l2_media - detach TIPC bearer from an L2 interface
421  *
422  * Mark L2 bearer as inactive so that incoming buffers are thrown away
423  */
424 void tipc_disable_l2_media(struct tipc_bearer *b)
425 {
426 	struct net_device *dev;
427 
428 	dev = (struct net_device *)rtnl_dereference(b->media_ptr);
429 	dev_remove_pack(&b->pt);
430 	RCU_INIT_POINTER(dev->tipc_ptr, NULL);
431 	synchronize_net();
432 	dev_put(dev);
433 }
434 
435 /**
436  * tipc_l2_send_msg - send a TIPC packet out over an L2 interface
437  * @skb: the packet to be sent
438  * @b: the bearer through which the packet is to be sent
439  * @dest: peer destination address
440  */
441 int tipc_l2_send_msg(struct net *net, struct sk_buff *skb,
442 		     struct tipc_bearer *b, struct tipc_media_addr *dest)
443 {
444 	struct net_device *dev;
445 	int delta;
446 
447 	dev = (struct net_device *)rcu_dereference_rtnl(b->media_ptr);
448 	if (!dev)
449 		return 0;
450 
451 	delta = SKB_DATA_ALIGN(dev->hard_header_len - skb_headroom(skb));
452 	if ((delta > 0) && pskb_expand_head(skb, delta, 0, GFP_ATOMIC)) {
453 		kfree_skb(skb);
454 		return 0;
455 	}
456 	skb_reset_network_header(skb);
457 	skb->dev = dev;
458 	skb->protocol = htons(ETH_P_TIPC);
459 	dev_hard_header(skb, dev, ETH_P_TIPC, dest->value,
460 			dev->dev_addr, skb->len);
461 	dev_queue_xmit(skb);
462 	return 0;
463 }
464 
465 bool tipc_bearer_bcast_support(struct net *net, u32 bearer_id)
466 {
467 	bool supp = false;
468 	struct tipc_bearer *b;
469 
470 	rcu_read_lock();
471 	b = bearer_get(net, bearer_id);
472 	if (b)
473 		supp = (b->bcast_addr.broadcast == TIPC_BROADCAST_SUPPORT);
474 	rcu_read_unlock();
475 	return supp;
476 }
477 
478 int tipc_bearer_mtu(struct net *net, u32 bearer_id)
479 {
480 	int mtu = 0;
481 	struct tipc_bearer *b;
482 
483 	rcu_read_lock();
484 	b = rcu_dereference_rtnl(tipc_net(net)->bearer_list[bearer_id]);
485 	if (b)
486 		mtu = b->mtu;
487 	rcu_read_unlock();
488 	return mtu;
489 }
490 
491 /* tipc_bearer_xmit_skb - sends buffer to destination over bearer
492  */
493 void tipc_bearer_xmit_skb(struct net *net, u32 bearer_id,
494 			  struct sk_buff *skb,
495 			  struct tipc_media_addr *dest)
496 {
497 	struct tipc_msg *hdr = buf_msg(skb);
498 	struct tipc_bearer *b;
499 
500 	rcu_read_lock();
501 	b = bearer_get(net, bearer_id);
502 	if (likely(b && (test_bit(0, &b->up) || msg_is_reset(hdr))))
503 		b->media->send_msg(net, skb, b, dest);
504 	else
505 		kfree_skb(skb);
506 	rcu_read_unlock();
507 }
508 
509 /* tipc_bearer_xmit() -send buffer to destination over bearer
510  */
511 void tipc_bearer_xmit(struct net *net, u32 bearer_id,
512 		      struct sk_buff_head *xmitq,
513 		      struct tipc_media_addr *dst)
514 {
515 	struct tipc_bearer *b;
516 	struct sk_buff *skb, *tmp;
517 
518 	if (skb_queue_empty(xmitq))
519 		return;
520 
521 	rcu_read_lock();
522 	b = bearer_get(net, bearer_id);
523 	if (unlikely(!b))
524 		__skb_queue_purge(xmitq);
525 	skb_queue_walk_safe(xmitq, skb, tmp) {
526 		__skb_dequeue(xmitq);
527 		if (likely(test_bit(0, &b->up) || msg_is_reset(buf_msg(skb))))
528 			b->media->send_msg(net, skb, b, dst);
529 		else
530 			kfree_skb(skb);
531 	}
532 	rcu_read_unlock();
533 }
534 
535 /* tipc_bearer_bc_xmit() - broadcast buffers to all destinations
536  */
537 void tipc_bearer_bc_xmit(struct net *net, u32 bearer_id,
538 			 struct sk_buff_head *xmitq)
539 {
540 	struct tipc_net *tn = tipc_net(net);
541 	int net_id = tn->net_id;
542 	struct tipc_bearer *b;
543 	struct sk_buff *skb, *tmp;
544 	struct tipc_msg *hdr;
545 
546 	rcu_read_lock();
547 	b = bearer_get(net, bearer_id);
548 	if (unlikely(!b || !test_bit(0, &b->up)))
549 		__skb_queue_purge(xmitq);
550 	skb_queue_walk_safe(xmitq, skb, tmp) {
551 		hdr = buf_msg(skb);
552 		msg_set_non_seq(hdr, 1);
553 		msg_set_mc_netid(hdr, net_id);
554 		__skb_dequeue(xmitq);
555 		b->media->send_msg(net, skb, b, &b->bcast_addr);
556 	}
557 	rcu_read_unlock();
558 }
559 
560 /**
561  * tipc_l2_rcv_msg - handle incoming TIPC message from an interface
562  * @buf: the received packet
563  * @dev: the net device that the packet was received on
564  * @pt: the packet_type structure which was used to register this handler
565  * @orig_dev: the original receive net device in case the device is a bond
566  *
567  * Accept only packets explicitly sent to this node, or broadcast packets;
568  * ignores packets sent using interface multicast, and traffic sent to other
569  * nodes (which can happen if interface is running in promiscuous mode).
570  */
571 static int tipc_l2_rcv_msg(struct sk_buff *skb, struct net_device *dev,
572 			   struct packet_type *pt, struct net_device *orig_dev)
573 {
574 	struct tipc_bearer *b;
575 
576 	rcu_read_lock();
577 	b = rcu_dereference_rtnl(dev->tipc_ptr) ?:
578 		rcu_dereference_rtnl(orig_dev->tipc_ptr);
579 	if (likely(b && test_bit(0, &b->up) &&
580 		   (skb->pkt_type <= PACKET_MULTICAST))) {
581 		skb_mark_not_on_list(skb);
582 		tipc_rcv(dev_net(b->pt.dev), skb, b);
583 		rcu_read_unlock();
584 		return NET_RX_SUCCESS;
585 	}
586 	rcu_read_unlock();
587 	kfree_skb(skb);
588 	return NET_RX_DROP;
589 }
590 
591 /**
592  * tipc_l2_device_event - handle device events from network device
593  * @nb: the context of the notification
594  * @evt: the type of event
595  * @ptr: the net device that the event was on
596  *
597  * This function is called by the Ethernet driver in case of link
598  * change event.
599  */
600 static int tipc_l2_device_event(struct notifier_block *nb, unsigned long evt,
601 				void *ptr)
602 {
603 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
604 	struct net *net = dev_net(dev);
605 	struct tipc_bearer *b;
606 
607 	b = rtnl_dereference(dev->tipc_ptr);
608 	if (!b)
609 		return NOTIFY_DONE;
610 
611 	trace_tipc_l2_device_event(dev, b, evt);
612 	switch (evt) {
613 	case NETDEV_CHANGE:
614 		if (netif_carrier_ok(dev) && netif_oper_up(dev)) {
615 			test_and_set_bit_lock(0, &b->up);
616 			break;
617 		}
618 		/* fall through */
619 	case NETDEV_GOING_DOWN:
620 		clear_bit_unlock(0, &b->up);
621 		tipc_reset_bearer(net, b);
622 		break;
623 	case NETDEV_UP:
624 		test_and_set_bit_lock(0, &b->up);
625 		break;
626 	case NETDEV_CHANGEMTU:
627 		if (tipc_mtu_bad(dev, 0)) {
628 			bearer_disable(net, b);
629 			break;
630 		}
631 		b->mtu = dev->mtu;
632 		tipc_reset_bearer(net, b);
633 		break;
634 	case NETDEV_CHANGEADDR:
635 		b->media->raw2addr(b, &b->addr,
636 				   (char *)dev->dev_addr);
637 		tipc_reset_bearer(net, b);
638 		break;
639 	case NETDEV_UNREGISTER:
640 	case NETDEV_CHANGENAME:
641 		bearer_disable(net, b);
642 		break;
643 	}
644 	return NOTIFY_OK;
645 }
646 
647 static struct notifier_block notifier = {
648 	.notifier_call  = tipc_l2_device_event,
649 	.priority	= 0,
650 };
651 
652 int tipc_bearer_setup(void)
653 {
654 	return register_netdevice_notifier(&notifier);
655 }
656 
657 void tipc_bearer_cleanup(void)
658 {
659 	unregister_netdevice_notifier(&notifier);
660 }
661 
662 void tipc_bearer_stop(struct net *net)
663 {
664 	struct tipc_net *tn = net_generic(net, tipc_net_id);
665 	struct tipc_bearer *b;
666 	u32 i;
667 
668 	for (i = 0; i < MAX_BEARERS; i++) {
669 		b = rtnl_dereference(tn->bearer_list[i]);
670 		if (b) {
671 			bearer_disable(net, b);
672 			tn->bearer_list[i] = NULL;
673 		}
674 	}
675 }
676 
677 /* Caller should hold rtnl_lock to protect the bearer */
678 static int __tipc_nl_add_bearer(struct tipc_nl_msg *msg,
679 				struct tipc_bearer *bearer, int nlflags)
680 {
681 	void *hdr;
682 	struct nlattr *attrs;
683 	struct nlattr *prop;
684 
685 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
686 			  nlflags, TIPC_NL_BEARER_GET);
687 	if (!hdr)
688 		return -EMSGSIZE;
689 
690 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_BEARER);
691 	if (!attrs)
692 		goto msg_full;
693 
694 	if (nla_put_string(msg->skb, TIPC_NLA_BEARER_NAME, bearer->name))
695 		goto attr_msg_full;
696 
697 	prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_BEARER_PROP);
698 	if (!prop)
699 		goto prop_msg_full;
700 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, bearer->priority))
701 		goto prop_msg_full;
702 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, bearer->tolerance))
703 		goto prop_msg_full;
704 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bearer->window))
705 		goto prop_msg_full;
706 	if (bearer->media->type_id == TIPC_MEDIA_TYPE_UDP)
707 		if (nla_put_u32(msg->skb, TIPC_NLA_PROP_MTU, bearer->mtu))
708 			goto prop_msg_full;
709 
710 	nla_nest_end(msg->skb, prop);
711 
712 #ifdef CONFIG_TIPC_MEDIA_UDP
713 	if (bearer->media->type_id == TIPC_MEDIA_TYPE_UDP) {
714 		if (tipc_udp_nl_add_bearer_data(msg, bearer))
715 			goto attr_msg_full;
716 	}
717 #endif
718 
719 	nla_nest_end(msg->skb, attrs);
720 	genlmsg_end(msg->skb, hdr);
721 
722 	return 0;
723 
724 prop_msg_full:
725 	nla_nest_cancel(msg->skb, prop);
726 attr_msg_full:
727 	nla_nest_cancel(msg->skb, attrs);
728 msg_full:
729 	genlmsg_cancel(msg->skb, hdr);
730 
731 	return -EMSGSIZE;
732 }
733 
734 int tipc_nl_bearer_dump(struct sk_buff *skb, struct netlink_callback *cb)
735 {
736 	int err;
737 	int i = cb->args[0];
738 	struct tipc_bearer *bearer;
739 	struct tipc_nl_msg msg;
740 	struct net *net = sock_net(skb->sk);
741 	struct tipc_net *tn = net_generic(net, tipc_net_id);
742 
743 	if (i == MAX_BEARERS)
744 		return 0;
745 
746 	msg.skb = skb;
747 	msg.portid = NETLINK_CB(cb->skb).portid;
748 	msg.seq = cb->nlh->nlmsg_seq;
749 
750 	rtnl_lock();
751 	for (i = 0; i < MAX_BEARERS; i++) {
752 		bearer = rtnl_dereference(tn->bearer_list[i]);
753 		if (!bearer)
754 			continue;
755 
756 		err = __tipc_nl_add_bearer(&msg, bearer, NLM_F_MULTI);
757 		if (err)
758 			break;
759 	}
760 	rtnl_unlock();
761 
762 	cb->args[0] = i;
763 	return skb->len;
764 }
765 
766 int tipc_nl_bearer_get(struct sk_buff *skb, struct genl_info *info)
767 {
768 	int err;
769 	char *name;
770 	struct sk_buff *rep;
771 	struct tipc_bearer *bearer;
772 	struct tipc_nl_msg msg;
773 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
774 	struct net *net = genl_info_net(info);
775 
776 	if (!info->attrs[TIPC_NLA_BEARER])
777 		return -EINVAL;
778 
779 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
780 					  info->attrs[TIPC_NLA_BEARER],
781 					  tipc_nl_bearer_policy, info->extack);
782 	if (err)
783 		return err;
784 
785 	if (!attrs[TIPC_NLA_BEARER_NAME])
786 		return -EINVAL;
787 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
788 
789 	rep = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
790 	if (!rep)
791 		return -ENOMEM;
792 
793 	msg.skb = rep;
794 	msg.portid = info->snd_portid;
795 	msg.seq = info->snd_seq;
796 
797 	rtnl_lock();
798 	bearer = tipc_bearer_find(net, name);
799 	if (!bearer) {
800 		err = -EINVAL;
801 		goto err_out;
802 	}
803 
804 	err = __tipc_nl_add_bearer(&msg, bearer, 0);
805 	if (err)
806 		goto err_out;
807 	rtnl_unlock();
808 
809 	return genlmsg_reply(rep, info);
810 err_out:
811 	rtnl_unlock();
812 	nlmsg_free(rep);
813 
814 	return err;
815 }
816 
817 int __tipc_nl_bearer_disable(struct sk_buff *skb, struct genl_info *info)
818 {
819 	int err;
820 	char *name;
821 	struct tipc_bearer *bearer;
822 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
823 	struct net *net = sock_net(skb->sk);
824 
825 	if (!info->attrs[TIPC_NLA_BEARER])
826 		return -EINVAL;
827 
828 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
829 					  info->attrs[TIPC_NLA_BEARER],
830 					  tipc_nl_bearer_policy, info->extack);
831 	if (err)
832 		return err;
833 
834 	if (!attrs[TIPC_NLA_BEARER_NAME])
835 		return -EINVAL;
836 
837 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
838 
839 	bearer = tipc_bearer_find(net, name);
840 	if (!bearer)
841 		return -EINVAL;
842 
843 	bearer_disable(net, bearer);
844 
845 	return 0;
846 }
847 
848 int tipc_nl_bearer_disable(struct sk_buff *skb, struct genl_info *info)
849 {
850 	int err;
851 
852 	rtnl_lock();
853 	err = __tipc_nl_bearer_disable(skb, info);
854 	rtnl_unlock();
855 
856 	return err;
857 }
858 
859 int __tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info)
860 {
861 	int err;
862 	char *bearer;
863 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
864 	struct net *net = sock_net(skb->sk);
865 	u32 domain = 0;
866 	u32 prio;
867 
868 	prio = TIPC_MEDIA_LINK_PRI;
869 
870 	if (!info->attrs[TIPC_NLA_BEARER])
871 		return -EINVAL;
872 
873 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
874 					  info->attrs[TIPC_NLA_BEARER],
875 					  tipc_nl_bearer_policy, info->extack);
876 	if (err)
877 		return err;
878 
879 	if (!attrs[TIPC_NLA_BEARER_NAME])
880 		return -EINVAL;
881 
882 	bearer = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
883 
884 	if (attrs[TIPC_NLA_BEARER_DOMAIN])
885 		domain = nla_get_u32(attrs[TIPC_NLA_BEARER_DOMAIN]);
886 
887 	if (attrs[TIPC_NLA_BEARER_PROP]) {
888 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
889 
890 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_BEARER_PROP],
891 					      props);
892 		if (err)
893 			return err;
894 
895 		if (props[TIPC_NLA_PROP_PRIO])
896 			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
897 	}
898 
899 	return tipc_enable_bearer(net, bearer, domain, prio, attrs);
900 }
901 
902 int tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info)
903 {
904 	int err;
905 
906 	rtnl_lock();
907 	err = __tipc_nl_bearer_enable(skb, info);
908 	rtnl_unlock();
909 
910 	return err;
911 }
912 
913 int tipc_nl_bearer_add(struct sk_buff *skb, struct genl_info *info)
914 {
915 	int err;
916 	char *name;
917 	struct tipc_bearer *b;
918 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
919 	struct net *net = sock_net(skb->sk);
920 
921 	if (!info->attrs[TIPC_NLA_BEARER])
922 		return -EINVAL;
923 
924 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
925 					  info->attrs[TIPC_NLA_BEARER],
926 					  tipc_nl_bearer_policy, info->extack);
927 	if (err)
928 		return err;
929 
930 	if (!attrs[TIPC_NLA_BEARER_NAME])
931 		return -EINVAL;
932 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
933 
934 	rtnl_lock();
935 	b = tipc_bearer_find(net, name);
936 	if (!b) {
937 		rtnl_unlock();
938 		return -EINVAL;
939 	}
940 
941 #ifdef CONFIG_TIPC_MEDIA_UDP
942 	if (attrs[TIPC_NLA_BEARER_UDP_OPTS]) {
943 		err = tipc_udp_nl_bearer_add(b,
944 					     attrs[TIPC_NLA_BEARER_UDP_OPTS]);
945 		if (err) {
946 			rtnl_unlock();
947 			return err;
948 		}
949 	}
950 #endif
951 	rtnl_unlock();
952 
953 	return 0;
954 }
955 
956 int __tipc_nl_bearer_set(struct sk_buff *skb, struct genl_info *info)
957 {
958 	struct tipc_bearer *b;
959 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
960 	struct net *net = sock_net(skb->sk);
961 	char *name;
962 	int err;
963 
964 	if (!info->attrs[TIPC_NLA_BEARER])
965 		return -EINVAL;
966 
967 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
968 					  info->attrs[TIPC_NLA_BEARER],
969 					  tipc_nl_bearer_policy, info->extack);
970 	if (err)
971 		return err;
972 
973 	if (!attrs[TIPC_NLA_BEARER_NAME])
974 		return -EINVAL;
975 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
976 
977 	b = tipc_bearer_find(net, name);
978 	if (!b)
979 		return -EINVAL;
980 
981 	if (attrs[TIPC_NLA_BEARER_PROP]) {
982 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
983 
984 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_BEARER_PROP],
985 					      props);
986 		if (err)
987 			return err;
988 
989 		if (props[TIPC_NLA_PROP_TOL]) {
990 			b->tolerance = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
991 			tipc_node_apply_property(net, b, TIPC_NLA_PROP_TOL);
992 		}
993 		if (props[TIPC_NLA_PROP_PRIO])
994 			b->priority = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
995 		if (props[TIPC_NLA_PROP_WIN])
996 			b->window = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
997 		if (props[TIPC_NLA_PROP_MTU]) {
998 			if (b->media->type_id != TIPC_MEDIA_TYPE_UDP)
999 				return -EINVAL;
1000 #ifdef CONFIG_TIPC_MEDIA_UDP
1001 			if (tipc_udp_mtu_bad(nla_get_u32
1002 					     (props[TIPC_NLA_PROP_MTU])))
1003 				return -EINVAL;
1004 			b->mtu = nla_get_u32(props[TIPC_NLA_PROP_MTU]);
1005 			tipc_node_apply_property(net, b, TIPC_NLA_PROP_MTU);
1006 #endif
1007 		}
1008 	}
1009 
1010 	return 0;
1011 }
1012 
1013 int tipc_nl_bearer_set(struct sk_buff *skb, struct genl_info *info)
1014 {
1015 	int err;
1016 
1017 	rtnl_lock();
1018 	err = __tipc_nl_bearer_set(skb, info);
1019 	rtnl_unlock();
1020 
1021 	return err;
1022 }
1023 
1024 static int __tipc_nl_add_media(struct tipc_nl_msg *msg,
1025 			       struct tipc_media *media, int nlflags)
1026 {
1027 	void *hdr;
1028 	struct nlattr *attrs;
1029 	struct nlattr *prop;
1030 
1031 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1032 			  nlflags, TIPC_NL_MEDIA_GET);
1033 	if (!hdr)
1034 		return -EMSGSIZE;
1035 
1036 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_MEDIA);
1037 	if (!attrs)
1038 		goto msg_full;
1039 
1040 	if (nla_put_string(msg->skb, TIPC_NLA_MEDIA_NAME, media->name))
1041 		goto attr_msg_full;
1042 
1043 	prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_MEDIA_PROP);
1044 	if (!prop)
1045 		goto prop_msg_full;
1046 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, media->priority))
1047 		goto prop_msg_full;
1048 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, media->tolerance))
1049 		goto prop_msg_full;
1050 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, media->window))
1051 		goto prop_msg_full;
1052 	if (media->type_id == TIPC_MEDIA_TYPE_UDP)
1053 		if (nla_put_u32(msg->skb, TIPC_NLA_PROP_MTU, media->mtu))
1054 			goto prop_msg_full;
1055 
1056 	nla_nest_end(msg->skb, prop);
1057 	nla_nest_end(msg->skb, attrs);
1058 	genlmsg_end(msg->skb, hdr);
1059 
1060 	return 0;
1061 
1062 prop_msg_full:
1063 	nla_nest_cancel(msg->skb, prop);
1064 attr_msg_full:
1065 	nla_nest_cancel(msg->skb, attrs);
1066 msg_full:
1067 	genlmsg_cancel(msg->skb, hdr);
1068 
1069 	return -EMSGSIZE;
1070 }
1071 
1072 int tipc_nl_media_dump(struct sk_buff *skb, struct netlink_callback *cb)
1073 {
1074 	int err;
1075 	int i = cb->args[0];
1076 	struct tipc_nl_msg msg;
1077 
1078 	if (i == MAX_MEDIA)
1079 		return 0;
1080 
1081 	msg.skb = skb;
1082 	msg.portid = NETLINK_CB(cb->skb).portid;
1083 	msg.seq = cb->nlh->nlmsg_seq;
1084 
1085 	rtnl_lock();
1086 	for (; media_info_array[i] != NULL; i++) {
1087 		err = __tipc_nl_add_media(&msg, media_info_array[i],
1088 					  NLM_F_MULTI);
1089 		if (err)
1090 			break;
1091 	}
1092 	rtnl_unlock();
1093 
1094 	cb->args[0] = i;
1095 	return skb->len;
1096 }
1097 
1098 int tipc_nl_media_get(struct sk_buff *skb, struct genl_info *info)
1099 {
1100 	int err;
1101 	char *name;
1102 	struct tipc_nl_msg msg;
1103 	struct tipc_media *media;
1104 	struct sk_buff *rep;
1105 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
1106 
1107 	if (!info->attrs[TIPC_NLA_MEDIA])
1108 		return -EINVAL;
1109 
1110 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_MEDIA_MAX,
1111 					  info->attrs[TIPC_NLA_MEDIA],
1112 					  tipc_nl_media_policy, info->extack);
1113 	if (err)
1114 		return err;
1115 
1116 	if (!attrs[TIPC_NLA_MEDIA_NAME])
1117 		return -EINVAL;
1118 	name = nla_data(attrs[TIPC_NLA_MEDIA_NAME]);
1119 
1120 	rep = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
1121 	if (!rep)
1122 		return -ENOMEM;
1123 
1124 	msg.skb = rep;
1125 	msg.portid = info->snd_portid;
1126 	msg.seq = info->snd_seq;
1127 
1128 	rtnl_lock();
1129 	media = tipc_media_find(name);
1130 	if (!media) {
1131 		err = -EINVAL;
1132 		goto err_out;
1133 	}
1134 
1135 	err = __tipc_nl_add_media(&msg, media, 0);
1136 	if (err)
1137 		goto err_out;
1138 	rtnl_unlock();
1139 
1140 	return genlmsg_reply(rep, info);
1141 err_out:
1142 	rtnl_unlock();
1143 	nlmsg_free(rep);
1144 
1145 	return err;
1146 }
1147 
1148 int __tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info)
1149 {
1150 	int err;
1151 	char *name;
1152 	struct tipc_media *m;
1153 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
1154 
1155 	if (!info->attrs[TIPC_NLA_MEDIA])
1156 		return -EINVAL;
1157 
1158 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_MEDIA_MAX,
1159 					  info->attrs[TIPC_NLA_MEDIA],
1160 					  tipc_nl_media_policy, info->extack);
1161 
1162 	if (!attrs[TIPC_NLA_MEDIA_NAME])
1163 		return -EINVAL;
1164 	name = nla_data(attrs[TIPC_NLA_MEDIA_NAME]);
1165 
1166 	m = tipc_media_find(name);
1167 	if (!m)
1168 		return -EINVAL;
1169 
1170 	if (attrs[TIPC_NLA_MEDIA_PROP]) {
1171 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
1172 
1173 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_MEDIA_PROP],
1174 					      props);
1175 		if (err)
1176 			return err;
1177 
1178 		if (props[TIPC_NLA_PROP_TOL])
1179 			m->tolerance = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1180 		if (props[TIPC_NLA_PROP_PRIO])
1181 			m->priority = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1182 		if (props[TIPC_NLA_PROP_WIN])
1183 			m->window = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1184 		if (props[TIPC_NLA_PROP_MTU]) {
1185 			if (m->type_id != TIPC_MEDIA_TYPE_UDP)
1186 				return -EINVAL;
1187 #ifdef CONFIG_TIPC_MEDIA_UDP
1188 			if (tipc_udp_mtu_bad(nla_get_u32
1189 					     (props[TIPC_NLA_PROP_MTU])))
1190 				return -EINVAL;
1191 			m->mtu = nla_get_u32(props[TIPC_NLA_PROP_MTU]);
1192 #endif
1193 		}
1194 	}
1195 
1196 	return 0;
1197 }
1198 
1199 int tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info)
1200 {
1201 	int err;
1202 
1203 	rtnl_lock();
1204 	err = __tipc_nl_media_set(skb, info);
1205 	rtnl_unlock();
1206 
1207 	return err;
1208 }
1209