xref: /openbmc/linux/net/tipc/bearer.c (revision 3dc4b6fb)
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(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(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(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 	if (dev == net->loopback_dev) {
393 		dev_put(dev);
394 		pr_info("Enabling <%s> not permitted\n", b->name);
395 		return -EINVAL;
396 	}
397 
398 	/* Autoconfigure own node identity if needed */
399 	if (!tipc_own_id(net) && hwaddr_len <= NODE_ID_LEN) {
400 		memcpy(node_id, dev->dev_addr, hwaddr_len);
401 		tipc_net_init(net, node_id, 0);
402 	}
403 	if (!tipc_own_id(net)) {
404 		dev_put(dev);
405 		pr_warn("Failed to obtain node identity\n");
406 		return -EINVAL;
407 	}
408 
409 	/* Associate TIPC bearer with L2 bearer */
410 	rcu_assign_pointer(b->media_ptr, dev);
411 	b->pt.dev = dev;
412 	b->pt.type = htons(ETH_P_TIPC);
413 	b->pt.func = tipc_l2_rcv_msg;
414 	dev_add_pack(&b->pt);
415 	memset(&b->bcast_addr, 0, sizeof(b->bcast_addr));
416 	memcpy(b->bcast_addr.value, dev->broadcast, hwaddr_len);
417 	b->bcast_addr.media_id = b->media->type_id;
418 	b->bcast_addr.broadcast = TIPC_BROADCAST_SUPPORT;
419 	b->mtu = dev->mtu;
420 	b->media->raw2addr(b, &b->addr, (char *)dev->dev_addr);
421 	rcu_assign_pointer(dev->tipc_ptr, b);
422 	return 0;
423 }
424 
425 /* tipc_disable_l2_media - detach TIPC bearer from an L2 interface
426  *
427  * Mark L2 bearer as inactive so that incoming buffers are thrown away
428  */
429 void tipc_disable_l2_media(struct tipc_bearer *b)
430 {
431 	struct net_device *dev;
432 
433 	dev = (struct net_device *)rtnl_dereference(b->media_ptr);
434 	dev_remove_pack(&b->pt);
435 	RCU_INIT_POINTER(dev->tipc_ptr, NULL);
436 	synchronize_net();
437 	dev_put(dev);
438 }
439 
440 /**
441  * tipc_l2_send_msg - send a TIPC packet out over an L2 interface
442  * @skb: the packet to be sent
443  * @b: the bearer through which the packet is to be sent
444  * @dest: peer destination address
445  */
446 int tipc_l2_send_msg(struct net *net, struct sk_buff *skb,
447 		     struct tipc_bearer *b, struct tipc_media_addr *dest)
448 {
449 	struct net_device *dev;
450 	int delta;
451 
452 	dev = (struct net_device *)rcu_dereference(b->media_ptr);
453 	if (!dev)
454 		return 0;
455 
456 	delta = SKB_DATA_ALIGN(dev->hard_header_len - skb_headroom(skb));
457 	if ((delta > 0) && pskb_expand_head(skb, delta, 0, GFP_ATOMIC)) {
458 		kfree_skb(skb);
459 		return 0;
460 	}
461 	skb_reset_network_header(skb);
462 	skb->dev = dev;
463 	skb->protocol = htons(ETH_P_TIPC);
464 	dev_hard_header(skb, dev, ETH_P_TIPC, dest->value,
465 			dev->dev_addr, skb->len);
466 	dev_queue_xmit(skb);
467 	return 0;
468 }
469 
470 bool tipc_bearer_bcast_support(struct net *net, u32 bearer_id)
471 {
472 	bool supp = false;
473 	struct tipc_bearer *b;
474 
475 	rcu_read_lock();
476 	b = bearer_get(net, bearer_id);
477 	if (b)
478 		supp = (b->bcast_addr.broadcast == TIPC_BROADCAST_SUPPORT);
479 	rcu_read_unlock();
480 	return supp;
481 }
482 
483 int tipc_bearer_mtu(struct net *net, u32 bearer_id)
484 {
485 	int mtu = 0;
486 	struct tipc_bearer *b;
487 
488 	rcu_read_lock();
489 	b = rcu_dereference(tipc_net(net)->bearer_list[bearer_id]);
490 	if (b)
491 		mtu = b->mtu;
492 	rcu_read_unlock();
493 	return mtu;
494 }
495 
496 /* tipc_bearer_xmit_skb - sends buffer to destination over bearer
497  */
498 void tipc_bearer_xmit_skb(struct net *net, u32 bearer_id,
499 			  struct sk_buff *skb,
500 			  struct tipc_media_addr *dest)
501 {
502 	struct tipc_msg *hdr = buf_msg(skb);
503 	struct tipc_bearer *b;
504 
505 	rcu_read_lock();
506 	b = bearer_get(net, bearer_id);
507 	if (likely(b && (test_bit(0, &b->up) || msg_is_reset(hdr))))
508 		b->media->send_msg(net, skb, b, dest);
509 	else
510 		kfree_skb(skb);
511 	rcu_read_unlock();
512 }
513 
514 /* tipc_bearer_xmit() -send buffer to destination over bearer
515  */
516 void tipc_bearer_xmit(struct net *net, u32 bearer_id,
517 		      struct sk_buff_head *xmitq,
518 		      struct tipc_media_addr *dst)
519 {
520 	struct tipc_bearer *b;
521 	struct sk_buff *skb, *tmp;
522 
523 	if (skb_queue_empty(xmitq))
524 		return;
525 
526 	rcu_read_lock();
527 	b = bearer_get(net, bearer_id);
528 	if (unlikely(!b))
529 		__skb_queue_purge(xmitq);
530 	skb_queue_walk_safe(xmitq, skb, tmp) {
531 		__skb_dequeue(xmitq);
532 		if (likely(test_bit(0, &b->up) || msg_is_reset(buf_msg(skb))))
533 			b->media->send_msg(net, skb, b, dst);
534 		else
535 			kfree_skb(skb);
536 	}
537 	rcu_read_unlock();
538 }
539 
540 /* tipc_bearer_bc_xmit() - broadcast buffers to all destinations
541  */
542 void tipc_bearer_bc_xmit(struct net *net, u32 bearer_id,
543 			 struct sk_buff_head *xmitq)
544 {
545 	struct tipc_net *tn = tipc_net(net);
546 	int net_id = tn->net_id;
547 	struct tipc_bearer *b;
548 	struct sk_buff *skb, *tmp;
549 	struct tipc_msg *hdr;
550 
551 	rcu_read_lock();
552 	b = bearer_get(net, bearer_id);
553 	if (unlikely(!b || !test_bit(0, &b->up)))
554 		__skb_queue_purge(xmitq);
555 	skb_queue_walk_safe(xmitq, skb, tmp) {
556 		hdr = buf_msg(skb);
557 		msg_set_non_seq(hdr, 1);
558 		msg_set_mc_netid(hdr, net_id);
559 		__skb_dequeue(xmitq);
560 		b->media->send_msg(net, skb, b, &b->bcast_addr);
561 	}
562 	rcu_read_unlock();
563 }
564 
565 /**
566  * tipc_l2_rcv_msg - handle incoming TIPC message from an interface
567  * @buf: the received packet
568  * @dev: the net device that the packet was received on
569  * @pt: the packet_type structure which was used to register this handler
570  * @orig_dev: the original receive net device in case the device is a bond
571  *
572  * Accept only packets explicitly sent to this node, or broadcast packets;
573  * ignores packets sent using interface multicast, and traffic sent to other
574  * nodes (which can happen if interface is running in promiscuous mode).
575  */
576 static int tipc_l2_rcv_msg(struct sk_buff *skb, struct net_device *dev,
577 			   struct packet_type *pt, struct net_device *orig_dev)
578 {
579 	struct tipc_bearer *b;
580 
581 	rcu_read_lock();
582 	b = rcu_dereference(dev->tipc_ptr) ?:
583 		rcu_dereference(orig_dev->tipc_ptr);
584 	if (likely(b && test_bit(0, &b->up) &&
585 		   (skb->pkt_type <= PACKET_MULTICAST))) {
586 		skb_mark_not_on_list(skb);
587 		tipc_rcv(dev_net(b->pt.dev), skb, b);
588 		rcu_read_unlock();
589 		return NET_RX_SUCCESS;
590 	}
591 	rcu_read_unlock();
592 	kfree_skb(skb);
593 	return NET_RX_DROP;
594 }
595 
596 /**
597  * tipc_l2_device_event - handle device events from network device
598  * @nb: the context of the notification
599  * @evt: the type of event
600  * @ptr: the net device that the event was on
601  *
602  * This function is called by the Ethernet driver in case of link
603  * change event.
604  */
605 static int tipc_l2_device_event(struct notifier_block *nb, unsigned long evt,
606 				void *ptr)
607 {
608 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
609 	struct net *net = dev_net(dev);
610 	struct tipc_bearer *b;
611 
612 	b = rtnl_dereference(dev->tipc_ptr);
613 	if (!b)
614 		return NOTIFY_DONE;
615 
616 	trace_tipc_l2_device_event(dev, b, evt);
617 	switch (evt) {
618 	case NETDEV_CHANGE:
619 		if (netif_carrier_ok(dev) && netif_oper_up(dev)) {
620 			test_and_set_bit_lock(0, &b->up);
621 			break;
622 		}
623 		/* fall through */
624 	case NETDEV_GOING_DOWN:
625 		clear_bit_unlock(0, &b->up);
626 		tipc_reset_bearer(net, b);
627 		break;
628 	case NETDEV_UP:
629 		test_and_set_bit_lock(0, &b->up);
630 		break;
631 	case NETDEV_CHANGEMTU:
632 		if (tipc_mtu_bad(dev, 0)) {
633 			bearer_disable(net, b);
634 			break;
635 		}
636 		b->mtu = dev->mtu;
637 		tipc_reset_bearer(net, b);
638 		break;
639 	case NETDEV_CHANGEADDR:
640 		b->media->raw2addr(b, &b->addr,
641 				   (char *)dev->dev_addr);
642 		tipc_reset_bearer(net, b);
643 		break;
644 	case NETDEV_UNREGISTER:
645 	case NETDEV_CHANGENAME:
646 		bearer_disable(net, b);
647 		break;
648 	}
649 	return NOTIFY_OK;
650 }
651 
652 static struct notifier_block notifier = {
653 	.notifier_call  = tipc_l2_device_event,
654 	.priority	= 0,
655 };
656 
657 int tipc_bearer_setup(void)
658 {
659 	return register_netdevice_notifier(&notifier);
660 }
661 
662 void tipc_bearer_cleanup(void)
663 {
664 	unregister_netdevice_notifier(&notifier);
665 }
666 
667 void tipc_bearer_stop(struct net *net)
668 {
669 	struct tipc_net *tn = net_generic(net, tipc_net_id);
670 	struct tipc_bearer *b;
671 	u32 i;
672 
673 	for (i = 0; i < MAX_BEARERS; i++) {
674 		b = rtnl_dereference(tn->bearer_list[i]);
675 		if (b) {
676 			bearer_disable(net, b);
677 			tn->bearer_list[i] = NULL;
678 		}
679 	}
680 }
681 
682 void tipc_clone_to_loopback(struct net *net, struct sk_buff_head *pkts)
683 {
684 	struct net_device *dev = net->loopback_dev;
685 	struct sk_buff *skb, *_skb;
686 	int exp;
687 
688 	skb_queue_walk(pkts, _skb) {
689 		skb = pskb_copy(_skb, GFP_ATOMIC);
690 		if (!skb)
691 			continue;
692 
693 		exp = SKB_DATA_ALIGN(dev->hard_header_len - skb_headroom(skb));
694 		if (exp > 0 && pskb_expand_head(skb, exp, 0, GFP_ATOMIC)) {
695 			kfree_skb(skb);
696 			continue;
697 		}
698 
699 		skb_reset_network_header(skb);
700 		dev_hard_header(skb, dev, ETH_P_TIPC, dev->dev_addr,
701 				dev->dev_addr, skb->len);
702 		skb->dev = dev;
703 		skb->pkt_type = PACKET_HOST;
704 		skb->ip_summed = CHECKSUM_UNNECESSARY;
705 		skb->protocol = eth_type_trans(skb, dev);
706 		netif_rx_ni(skb);
707 	}
708 }
709 
710 static int tipc_loopback_rcv_pkt(struct sk_buff *skb, struct net_device *dev,
711 				 struct packet_type *pt, struct net_device *od)
712 {
713 	consume_skb(skb);
714 	return NET_RX_SUCCESS;
715 }
716 
717 int tipc_attach_loopback(struct net *net)
718 {
719 	struct net_device *dev = net->loopback_dev;
720 	struct tipc_net *tn = tipc_net(net);
721 
722 	if (!dev)
723 		return -ENODEV;
724 
725 	dev_hold(dev);
726 	tn->loopback_pt.dev = dev;
727 	tn->loopback_pt.type = htons(ETH_P_TIPC);
728 	tn->loopback_pt.func = tipc_loopback_rcv_pkt;
729 	dev_add_pack(&tn->loopback_pt);
730 	return 0;
731 }
732 
733 void tipc_detach_loopback(struct net *net)
734 {
735 	struct tipc_net *tn = tipc_net(net);
736 
737 	dev_remove_pack(&tn->loopback_pt);
738 	dev_put(net->loopback_dev);
739 }
740 
741 /* Caller should hold rtnl_lock to protect the bearer */
742 static int __tipc_nl_add_bearer(struct tipc_nl_msg *msg,
743 				struct tipc_bearer *bearer, int nlflags)
744 {
745 	void *hdr;
746 	struct nlattr *attrs;
747 	struct nlattr *prop;
748 
749 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
750 			  nlflags, TIPC_NL_BEARER_GET);
751 	if (!hdr)
752 		return -EMSGSIZE;
753 
754 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_BEARER);
755 	if (!attrs)
756 		goto msg_full;
757 
758 	if (nla_put_string(msg->skb, TIPC_NLA_BEARER_NAME, bearer->name))
759 		goto attr_msg_full;
760 
761 	prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_BEARER_PROP);
762 	if (!prop)
763 		goto prop_msg_full;
764 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, bearer->priority))
765 		goto prop_msg_full;
766 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, bearer->tolerance))
767 		goto prop_msg_full;
768 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bearer->window))
769 		goto prop_msg_full;
770 	if (bearer->media->type_id == TIPC_MEDIA_TYPE_UDP)
771 		if (nla_put_u32(msg->skb, TIPC_NLA_PROP_MTU, bearer->mtu))
772 			goto prop_msg_full;
773 
774 	nla_nest_end(msg->skb, prop);
775 
776 #ifdef CONFIG_TIPC_MEDIA_UDP
777 	if (bearer->media->type_id == TIPC_MEDIA_TYPE_UDP) {
778 		if (tipc_udp_nl_add_bearer_data(msg, bearer))
779 			goto attr_msg_full;
780 	}
781 #endif
782 
783 	nla_nest_end(msg->skb, attrs);
784 	genlmsg_end(msg->skb, hdr);
785 
786 	return 0;
787 
788 prop_msg_full:
789 	nla_nest_cancel(msg->skb, prop);
790 attr_msg_full:
791 	nla_nest_cancel(msg->skb, attrs);
792 msg_full:
793 	genlmsg_cancel(msg->skb, hdr);
794 
795 	return -EMSGSIZE;
796 }
797 
798 int tipc_nl_bearer_dump(struct sk_buff *skb, struct netlink_callback *cb)
799 {
800 	int err;
801 	int i = cb->args[0];
802 	struct tipc_bearer *bearer;
803 	struct tipc_nl_msg msg;
804 	struct net *net = sock_net(skb->sk);
805 	struct tipc_net *tn = net_generic(net, tipc_net_id);
806 
807 	if (i == MAX_BEARERS)
808 		return 0;
809 
810 	msg.skb = skb;
811 	msg.portid = NETLINK_CB(cb->skb).portid;
812 	msg.seq = cb->nlh->nlmsg_seq;
813 
814 	rtnl_lock();
815 	for (i = 0; i < MAX_BEARERS; i++) {
816 		bearer = rtnl_dereference(tn->bearer_list[i]);
817 		if (!bearer)
818 			continue;
819 
820 		err = __tipc_nl_add_bearer(&msg, bearer, NLM_F_MULTI);
821 		if (err)
822 			break;
823 	}
824 	rtnl_unlock();
825 
826 	cb->args[0] = i;
827 	return skb->len;
828 }
829 
830 int tipc_nl_bearer_get(struct sk_buff *skb, struct genl_info *info)
831 {
832 	int err;
833 	char *name;
834 	struct sk_buff *rep;
835 	struct tipc_bearer *bearer;
836 	struct tipc_nl_msg msg;
837 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
838 	struct net *net = genl_info_net(info);
839 
840 	if (!info->attrs[TIPC_NLA_BEARER])
841 		return -EINVAL;
842 
843 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
844 					  info->attrs[TIPC_NLA_BEARER],
845 					  tipc_nl_bearer_policy, info->extack);
846 	if (err)
847 		return err;
848 
849 	if (!attrs[TIPC_NLA_BEARER_NAME])
850 		return -EINVAL;
851 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
852 
853 	rep = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
854 	if (!rep)
855 		return -ENOMEM;
856 
857 	msg.skb = rep;
858 	msg.portid = info->snd_portid;
859 	msg.seq = info->snd_seq;
860 
861 	rtnl_lock();
862 	bearer = tipc_bearer_find(net, name);
863 	if (!bearer) {
864 		err = -EINVAL;
865 		goto err_out;
866 	}
867 
868 	err = __tipc_nl_add_bearer(&msg, bearer, 0);
869 	if (err)
870 		goto err_out;
871 	rtnl_unlock();
872 
873 	return genlmsg_reply(rep, info);
874 err_out:
875 	rtnl_unlock();
876 	nlmsg_free(rep);
877 
878 	return err;
879 }
880 
881 int __tipc_nl_bearer_disable(struct sk_buff *skb, struct genl_info *info)
882 {
883 	int err;
884 	char *name;
885 	struct tipc_bearer *bearer;
886 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
887 	struct net *net = sock_net(skb->sk);
888 
889 	if (!info->attrs[TIPC_NLA_BEARER])
890 		return -EINVAL;
891 
892 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
893 					  info->attrs[TIPC_NLA_BEARER],
894 					  tipc_nl_bearer_policy, info->extack);
895 	if (err)
896 		return err;
897 
898 	if (!attrs[TIPC_NLA_BEARER_NAME])
899 		return -EINVAL;
900 
901 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
902 
903 	bearer = tipc_bearer_find(net, name);
904 	if (!bearer)
905 		return -EINVAL;
906 
907 	bearer_disable(net, bearer);
908 
909 	return 0;
910 }
911 
912 int tipc_nl_bearer_disable(struct sk_buff *skb, struct genl_info *info)
913 {
914 	int err;
915 
916 	rtnl_lock();
917 	err = __tipc_nl_bearer_disable(skb, info);
918 	rtnl_unlock();
919 
920 	return err;
921 }
922 
923 int __tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info)
924 {
925 	int err;
926 	char *bearer;
927 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
928 	struct net *net = sock_net(skb->sk);
929 	u32 domain = 0;
930 	u32 prio;
931 
932 	prio = TIPC_MEDIA_LINK_PRI;
933 
934 	if (!info->attrs[TIPC_NLA_BEARER])
935 		return -EINVAL;
936 
937 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
938 					  info->attrs[TIPC_NLA_BEARER],
939 					  tipc_nl_bearer_policy, info->extack);
940 	if (err)
941 		return err;
942 
943 	if (!attrs[TIPC_NLA_BEARER_NAME])
944 		return -EINVAL;
945 
946 	bearer = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
947 
948 	if (attrs[TIPC_NLA_BEARER_DOMAIN])
949 		domain = nla_get_u32(attrs[TIPC_NLA_BEARER_DOMAIN]);
950 
951 	if (attrs[TIPC_NLA_BEARER_PROP]) {
952 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
953 
954 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_BEARER_PROP],
955 					      props);
956 		if (err)
957 			return err;
958 
959 		if (props[TIPC_NLA_PROP_PRIO])
960 			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
961 	}
962 
963 	return tipc_enable_bearer(net, bearer, domain, prio, attrs);
964 }
965 
966 int tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info)
967 {
968 	int err;
969 
970 	rtnl_lock();
971 	err = __tipc_nl_bearer_enable(skb, info);
972 	rtnl_unlock();
973 
974 	return err;
975 }
976 
977 int tipc_nl_bearer_add(struct sk_buff *skb, struct genl_info *info)
978 {
979 	int err;
980 	char *name;
981 	struct tipc_bearer *b;
982 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
983 	struct net *net = sock_net(skb->sk);
984 
985 	if (!info->attrs[TIPC_NLA_BEARER])
986 		return -EINVAL;
987 
988 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
989 					  info->attrs[TIPC_NLA_BEARER],
990 					  tipc_nl_bearer_policy, info->extack);
991 	if (err)
992 		return err;
993 
994 	if (!attrs[TIPC_NLA_BEARER_NAME])
995 		return -EINVAL;
996 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
997 
998 	rtnl_lock();
999 	b = tipc_bearer_find(net, name);
1000 	if (!b) {
1001 		rtnl_unlock();
1002 		return -EINVAL;
1003 	}
1004 
1005 #ifdef CONFIG_TIPC_MEDIA_UDP
1006 	if (attrs[TIPC_NLA_BEARER_UDP_OPTS]) {
1007 		err = tipc_udp_nl_bearer_add(b,
1008 					     attrs[TIPC_NLA_BEARER_UDP_OPTS]);
1009 		if (err) {
1010 			rtnl_unlock();
1011 			return err;
1012 		}
1013 	}
1014 #endif
1015 	rtnl_unlock();
1016 
1017 	return 0;
1018 }
1019 
1020 int __tipc_nl_bearer_set(struct sk_buff *skb, struct genl_info *info)
1021 {
1022 	struct tipc_bearer *b;
1023 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
1024 	struct net *net = sock_net(skb->sk);
1025 	char *name;
1026 	int err;
1027 
1028 	if (!info->attrs[TIPC_NLA_BEARER])
1029 		return -EINVAL;
1030 
1031 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
1032 					  info->attrs[TIPC_NLA_BEARER],
1033 					  tipc_nl_bearer_policy, info->extack);
1034 	if (err)
1035 		return err;
1036 
1037 	if (!attrs[TIPC_NLA_BEARER_NAME])
1038 		return -EINVAL;
1039 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
1040 
1041 	b = tipc_bearer_find(net, name);
1042 	if (!b)
1043 		return -EINVAL;
1044 
1045 	if (attrs[TIPC_NLA_BEARER_PROP]) {
1046 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
1047 
1048 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_BEARER_PROP],
1049 					      props);
1050 		if (err)
1051 			return err;
1052 
1053 		if (props[TIPC_NLA_PROP_TOL]) {
1054 			b->tolerance = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1055 			tipc_node_apply_property(net, b, TIPC_NLA_PROP_TOL);
1056 		}
1057 		if (props[TIPC_NLA_PROP_PRIO])
1058 			b->priority = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1059 		if (props[TIPC_NLA_PROP_WIN])
1060 			b->window = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1061 		if (props[TIPC_NLA_PROP_MTU]) {
1062 			if (b->media->type_id != TIPC_MEDIA_TYPE_UDP)
1063 				return -EINVAL;
1064 #ifdef CONFIG_TIPC_MEDIA_UDP
1065 			if (tipc_udp_mtu_bad(nla_get_u32
1066 					     (props[TIPC_NLA_PROP_MTU])))
1067 				return -EINVAL;
1068 			b->mtu = nla_get_u32(props[TIPC_NLA_PROP_MTU]);
1069 			tipc_node_apply_property(net, b, TIPC_NLA_PROP_MTU);
1070 #endif
1071 		}
1072 	}
1073 
1074 	return 0;
1075 }
1076 
1077 int tipc_nl_bearer_set(struct sk_buff *skb, struct genl_info *info)
1078 {
1079 	int err;
1080 
1081 	rtnl_lock();
1082 	err = __tipc_nl_bearer_set(skb, info);
1083 	rtnl_unlock();
1084 
1085 	return err;
1086 }
1087 
1088 static int __tipc_nl_add_media(struct tipc_nl_msg *msg,
1089 			       struct tipc_media *media, int nlflags)
1090 {
1091 	void *hdr;
1092 	struct nlattr *attrs;
1093 	struct nlattr *prop;
1094 
1095 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1096 			  nlflags, TIPC_NL_MEDIA_GET);
1097 	if (!hdr)
1098 		return -EMSGSIZE;
1099 
1100 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_MEDIA);
1101 	if (!attrs)
1102 		goto msg_full;
1103 
1104 	if (nla_put_string(msg->skb, TIPC_NLA_MEDIA_NAME, media->name))
1105 		goto attr_msg_full;
1106 
1107 	prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_MEDIA_PROP);
1108 	if (!prop)
1109 		goto prop_msg_full;
1110 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, media->priority))
1111 		goto prop_msg_full;
1112 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, media->tolerance))
1113 		goto prop_msg_full;
1114 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, media->window))
1115 		goto prop_msg_full;
1116 	if (media->type_id == TIPC_MEDIA_TYPE_UDP)
1117 		if (nla_put_u32(msg->skb, TIPC_NLA_PROP_MTU, media->mtu))
1118 			goto prop_msg_full;
1119 
1120 	nla_nest_end(msg->skb, prop);
1121 	nla_nest_end(msg->skb, attrs);
1122 	genlmsg_end(msg->skb, hdr);
1123 
1124 	return 0;
1125 
1126 prop_msg_full:
1127 	nla_nest_cancel(msg->skb, prop);
1128 attr_msg_full:
1129 	nla_nest_cancel(msg->skb, attrs);
1130 msg_full:
1131 	genlmsg_cancel(msg->skb, hdr);
1132 
1133 	return -EMSGSIZE;
1134 }
1135 
1136 int tipc_nl_media_dump(struct sk_buff *skb, struct netlink_callback *cb)
1137 {
1138 	int err;
1139 	int i = cb->args[0];
1140 	struct tipc_nl_msg msg;
1141 
1142 	if (i == MAX_MEDIA)
1143 		return 0;
1144 
1145 	msg.skb = skb;
1146 	msg.portid = NETLINK_CB(cb->skb).portid;
1147 	msg.seq = cb->nlh->nlmsg_seq;
1148 
1149 	rtnl_lock();
1150 	for (; media_info_array[i] != NULL; i++) {
1151 		err = __tipc_nl_add_media(&msg, media_info_array[i],
1152 					  NLM_F_MULTI);
1153 		if (err)
1154 			break;
1155 	}
1156 	rtnl_unlock();
1157 
1158 	cb->args[0] = i;
1159 	return skb->len;
1160 }
1161 
1162 int tipc_nl_media_get(struct sk_buff *skb, struct genl_info *info)
1163 {
1164 	int err;
1165 	char *name;
1166 	struct tipc_nl_msg msg;
1167 	struct tipc_media *media;
1168 	struct sk_buff *rep;
1169 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
1170 
1171 	if (!info->attrs[TIPC_NLA_MEDIA])
1172 		return -EINVAL;
1173 
1174 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_MEDIA_MAX,
1175 					  info->attrs[TIPC_NLA_MEDIA],
1176 					  tipc_nl_media_policy, info->extack);
1177 	if (err)
1178 		return err;
1179 
1180 	if (!attrs[TIPC_NLA_MEDIA_NAME])
1181 		return -EINVAL;
1182 	name = nla_data(attrs[TIPC_NLA_MEDIA_NAME]);
1183 
1184 	rep = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
1185 	if (!rep)
1186 		return -ENOMEM;
1187 
1188 	msg.skb = rep;
1189 	msg.portid = info->snd_portid;
1190 	msg.seq = info->snd_seq;
1191 
1192 	rtnl_lock();
1193 	media = tipc_media_find(name);
1194 	if (!media) {
1195 		err = -EINVAL;
1196 		goto err_out;
1197 	}
1198 
1199 	err = __tipc_nl_add_media(&msg, media, 0);
1200 	if (err)
1201 		goto err_out;
1202 	rtnl_unlock();
1203 
1204 	return genlmsg_reply(rep, info);
1205 err_out:
1206 	rtnl_unlock();
1207 	nlmsg_free(rep);
1208 
1209 	return err;
1210 }
1211 
1212 int __tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info)
1213 {
1214 	int err;
1215 	char *name;
1216 	struct tipc_media *m;
1217 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
1218 
1219 	if (!info->attrs[TIPC_NLA_MEDIA])
1220 		return -EINVAL;
1221 
1222 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_MEDIA_MAX,
1223 					  info->attrs[TIPC_NLA_MEDIA],
1224 					  tipc_nl_media_policy, info->extack);
1225 
1226 	if (!attrs[TIPC_NLA_MEDIA_NAME])
1227 		return -EINVAL;
1228 	name = nla_data(attrs[TIPC_NLA_MEDIA_NAME]);
1229 
1230 	m = tipc_media_find(name);
1231 	if (!m)
1232 		return -EINVAL;
1233 
1234 	if (attrs[TIPC_NLA_MEDIA_PROP]) {
1235 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
1236 
1237 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_MEDIA_PROP],
1238 					      props);
1239 		if (err)
1240 			return err;
1241 
1242 		if (props[TIPC_NLA_PROP_TOL])
1243 			m->tolerance = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1244 		if (props[TIPC_NLA_PROP_PRIO])
1245 			m->priority = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1246 		if (props[TIPC_NLA_PROP_WIN])
1247 			m->window = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1248 		if (props[TIPC_NLA_PROP_MTU]) {
1249 			if (m->type_id != TIPC_MEDIA_TYPE_UDP)
1250 				return -EINVAL;
1251 #ifdef CONFIG_TIPC_MEDIA_UDP
1252 			if (tipc_udp_mtu_bad(nla_get_u32
1253 					     (props[TIPC_NLA_PROP_MTU])))
1254 				return -EINVAL;
1255 			m->mtu = nla_get_u32(props[TIPC_NLA_PROP_MTU]);
1256 #endif
1257 		}
1258 	}
1259 
1260 	return 0;
1261 }
1262 
1263 int tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info)
1264 {
1265 	int err;
1266 
1267 	rtnl_lock();
1268 	err = __tipc_nl_media_set(skb, info);
1269 	rtnl_unlock();
1270 
1271 	return err;
1272 }
1273