xref: /linux/net/tipc/bearer.c (revision 4c630f307455c06f99bdeca7f7a1ab5318604fe0)
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 #include "crypto.h"
48 
49 #define MAX_ADDR_STR 60
50 
51 static struct tipc_media * const media_info_array[] = {
52 	&eth_media_info,
53 #ifdef CONFIG_TIPC_MEDIA_IB
54 	&ib_media_info,
55 #endif
56 #ifdef CONFIG_TIPC_MEDIA_UDP
57 	&udp_media_info,
58 #endif
59 	NULL
60 };
61 
62 static struct tipc_bearer *bearer_get(struct net *net, int bearer_id)
63 {
64 	struct tipc_net *tn = tipc_net(net);
65 
66 	return rcu_dereference(tn->bearer_list[bearer_id]);
67 }
68 
69 static void bearer_disable(struct net *net, struct tipc_bearer *b);
70 static int tipc_l2_rcv_msg(struct sk_buff *skb, struct net_device *dev,
71 			   struct packet_type *pt, struct net_device *orig_dev);
72 
73 /**
74  * tipc_media_find - locates specified media object by name
75  * @name: name to locate
76  */
77 struct tipc_media *tipc_media_find(const char *name)
78 {
79 	u32 i;
80 
81 	for (i = 0; media_info_array[i] != NULL; i++) {
82 		if (!strcmp(media_info_array[i]->name, name))
83 			break;
84 	}
85 	return media_info_array[i];
86 }
87 
88 /**
89  * media_find_id - locates specified media object by type identifier
90  * @type: type identifier to locate
91  */
92 static struct tipc_media *media_find_id(u8 type)
93 {
94 	u32 i;
95 
96 	for (i = 0; media_info_array[i] != NULL; i++) {
97 		if (media_info_array[i]->type_id == type)
98 			break;
99 	}
100 	return media_info_array[i];
101 }
102 
103 /**
104  * tipc_media_addr_printf - record media address in print buffer
105  * @buf: output buffer
106  * @len: output buffer size remaining
107  * @a: input media address
108  */
109 int tipc_media_addr_printf(char *buf, int len, struct tipc_media_addr *a)
110 {
111 	char addr_str[MAX_ADDR_STR];
112 	struct tipc_media *m;
113 	int ret;
114 
115 	m = media_find_id(a->media_id);
116 
117 	if (m && !m->addr2str(a, addr_str, sizeof(addr_str)))
118 		ret = scnprintf(buf, len, "%s(%s)", m->name, addr_str);
119 	else {
120 		u32 i;
121 
122 		ret = scnprintf(buf, len, "UNKNOWN(%u)", a->media_id);
123 		for (i = 0; i < sizeof(a->value); i++)
124 			ret += scnprintf(buf + ret, len - ret,
125 					    "-%x", a->value[i]);
126 	}
127 	return ret;
128 }
129 
130 /**
131  * bearer_name_validate - validate & (optionally) deconstruct bearer name
132  * @name: ptr to bearer name string
133  * @name_parts: ptr to area for bearer name components (or NULL if not needed)
134  *
135  * Return: 1 if bearer name is valid, otherwise 0.
136  */
137 static int bearer_name_validate(const char *name,
138 				struct tipc_bearer_names *name_parts)
139 {
140 	char name_copy[TIPC_MAX_BEARER_NAME];
141 	char *media_name;
142 	char *if_name;
143 	u32 media_len;
144 	u32 if_len;
145 
146 	/* copy bearer name & ensure length is OK */
147 	if (strscpy(name_copy, name, TIPC_MAX_BEARER_NAME) < 0)
148 		return 0;
149 
150 	/* ensure all component parts of bearer name are present */
151 	media_name = name_copy;
152 	if_name = strchr(media_name, ':');
153 	if (if_name == NULL)
154 		return 0;
155 	*(if_name++) = 0;
156 	media_len = if_name - media_name;
157 	if_len = strlen(if_name) + 1;
158 
159 	/* validate component parts of bearer name */
160 	if ((media_len <= 1) || (media_len > TIPC_MAX_MEDIA_NAME) ||
161 	    (if_len <= 1) || (if_len > TIPC_MAX_IF_NAME))
162 		return 0;
163 
164 	/* return bearer name components, if necessary */
165 	if (name_parts) {
166 		strcpy(name_parts->media_name, media_name);
167 		strcpy(name_parts->if_name, if_name);
168 	}
169 	return 1;
170 }
171 
172 /**
173  * tipc_bearer_find - locates bearer object with matching bearer name
174  * @net: the applicable net namespace
175  * @name: bearer name to locate
176  */
177 struct tipc_bearer *tipc_bearer_find(struct net *net, const char *name)
178 {
179 	struct tipc_net *tn = net_generic(net, tipc_net_id);
180 	struct tipc_bearer *b;
181 	u32 i;
182 
183 	for (i = 0; i < MAX_BEARERS; i++) {
184 		b = rtnl_dereference(tn->bearer_list[i]);
185 		if (b && (!strcmp(b->name, name)))
186 			return b;
187 	}
188 	return NULL;
189 }
190 
191 /*     tipc_bearer_get_name - get the bearer name from its id.
192  *     @net: network namespace
193  *     @name: a pointer to the buffer where the name will be stored.
194  *     @bearer_id: the id to get the name from.
195  */
196 int tipc_bearer_get_name(struct net *net, char *name, u32 bearer_id)
197 {
198 	struct tipc_net *tn = tipc_net(net);
199 	struct tipc_bearer *b;
200 
201 	if (bearer_id >= MAX_BEARERS)
202 		return -EINVAL;
203 
204 	b = rtnl_dereference(tn->bearer_list[bearer_id]);
205 	if (!b)
206 		return -EINVAL;
207 
208 	strcpy(name, b->name);
209 	return 0;
210 }
211 
212 void tipc_bearer_add_dest(struct net *net, u32 bearer_id, u32 dest)
213 {
214 	struct tipc_net *tn = net_generic(net, tipc_net_id);
215 	struct tipc_bearer *b;
216 
217 	rcu_read_lock();
218 	b = rcu_dereference(tn->bearer_list[bearer_id]);
219 	if (b)
220 		tipc_disc_add_dest(b->disc);
221 	rcu_read_unlock();
222 }
223 
224 void tipc_bearer_remove_dest(struct net *net, u32 bearer_id, u32 dest)
225 {
226 	struct tipc_net *tn = net_generic(net, tipc_net_id);
227 	struct tipc_bearer *b;
228 
229 	rcu_read_lock();
230 	b = rcu_dereference(tn->bearer_list[bearer_id]);
231 	if (b)
232 		tipc_disc_remove_dest(b->disc);
233 	rcu_read_unlock();
234 }
235 
236 /**
237  * tipc_enable_bearer - enable bearer with the given name
238  * @net: the applicable net namespace
239  * @name: bearer name to enable
240  * @disc_domain: bearer domain
241  * @prio: bearer priority
242  * @attr: nlattr array
243  * @extack: netlink extended ack
244  */
245 static int tipc_enable_bearer(struct net *net, const char *name,
246 			      u32 disc_domain, u32 prio,
247 			      struct nlattr *attr[],
248 			      struct netlink_ext_ack *extack)
249 {
250 	struct tipc_net *tn = tipc_net(net);
251 	struct tipc_bearer_names b_names;
252 	int with_this_prio = 1;
253 	struct tipc_bearer *b;
254 	struct tipc_media *m;
255 	struct sk_buff *skb;
256 	int bearer_id = 0;
257 	int res = -EINVAL;
258 	char *errstr = "";
259 	u32 i;
260 
261 	if (!bearer_name_validate(name, &b_names)) {
262 		NL_SET_ERR_MSG(extack, "Illegal name");
263 		return res;
264 	}
265 
266 	if (prio > TIPC_MAX_LINK_PRI && prio != TIPC_MEDIA_LINK_PRI) {
267 		errstr = "illegal priority";
268 		NL_SET_ERR_MSG(extack, "Illegal priority");
269 		goto rejected;
270 	}
271 
272 	m = tipc_media_find(b_names.media_name);
273 	if (!m) {
274 		errstr = "media not registered";
275 		NL_SET_ERR_MSG(extack, "Media not registered");
276 		goto rejected;
277 	}
278 
279 	if (prio == TIPC_MEDIA_LINK_PRI)
280 		prio = m->priority;
281 
282 	/* Check new bearer vs existing ones and find free bearer id if any */
283 	bearer_id = MAX_BEARERS;
284 	i = MAX_BEARERS;
285 	while (i-- != 0) {
286 		b = rtnl_dereference(tn->bearer_list[i]);
287 		if (!b) {
288 			bearer_id = i;
289 			continue;
290 		}
291 		if (!strcmp(name, b->name)) {
292 			errstr = "already enabled";
293 			NL_SET_ERR_MSG(extack, "Already enabled");
294 			goto rejected;
295 		}
296 
297 		if (b->priority == prio &&
298 		    (++with_this_prio > 2)) {
299 			pr_warn("Bearer <%s>: already 2 bearers with priority %u\n",
300 				name, prio);
301 
302 			if (prio == TIPC_MIN_LINK_PRI) {
303 				errstr = "cannot adjust to lower";
304 				NL_SET_ERR_MSG(extack, "Cannot adjust to lower");
305 				goto rejected;
306 			}
307 
308 			pr_warn("Bearer <%s>: trying with adjusted priority\n",
309 				name);
310 			prio--;
311 			bearer_id = MAX_BEARERS;
312 			i = MAX_BEARERS;
313 			with_this_prio = 1;
314 		}
315 	}
316 
317 	if (bearer_id >= MAX_BEARERS) {
318 		errstr = "max 3 bearers permitted";
319 		NL_SET_ERR_MSG(extack, "Max 3 bearers permitted");
320 		goto rejected;
321 	}
322 
323 	b = kzalloc(sizeof(*b), GFP_ATOMIC);
324 	if (!b)
325 		return -ENOMEM;
326 
327 	strcpy(b->name, name);
328 	b->media = m;
329 	res = m->enable_media(net, b, attr);
330 	if (res) {
331 		kfree(b);
332 		errstr = "failed to enable media";
333 		NL_SET_ERR_MSG(extack, "Failed to enable media");
334 		goto rejected;
335 	}
336 
337 	b->identity = bearer_id;
338 	b->tolerance = m->tolerance;
339 	b->min_win = m->min_win;
340 	b->max_win = m->max_win;
341 	b->domain = disc_domain;
342 	b->net_plane = bearer_id + 'A';
343 	b->priority = prio;
344 	refcount_set(&b->refcnt, 1);
345 
346 	res = tipc_disc_create(net, b, &b->bcast_addr, &skb);
347 	if (res) {
348 		bearer_disable(net, b);
349 		errstr = "failed to create discoverer";
350 		NL_SET_ERR_MSG(extack, "Failed to create discoverer");
351 		goto rejected;
352 	}
353 
354 	/* Create monitoring data before accepting activate messages */
355 	if (tipc_mon_create(net, bearer_id)) {
356 		bearer_disable(net, b);
357 		kfree_skb(skb);
358 		return -ENOMEM;
359 	}
360 
361 	test_and_set_bit_lock(0, &b->up);
362 	rcu_assign_pointer(tn->bearer_list[bearer_id], b);
363 	if (skb)
364 		tipc_bearer_xmit_skb(net, bearer_id, skb, &b->bcast_addr);
365 
366 	pr_info("Enabled bearer <%s>, priority %u\n", name, prio);
367 
368 	return res;
369 rejected:
370 	pr_warn("Enabling of bearer <%s> rejected, %s\n", name, errstr);
371 	return res;
372 }
373 
374 /**
375  * tipc_reset_bearer - Reset all links established over this bearer
376  * @net: the applicable net namespace
377  * @b: the target bearer
378  */
379 static int tipc_reset_bearer(struct net *net, struct tipc_bearer *b)
380 {
381 	pr_info("Resetting bearer <%s>\n", b->name);
382 	tipc_node_delete_links(net, b->identity);
383 	tipc_disc_reset(net, b);
384 	return 0;
385 }
386 
387 bool tipc_bearer_hold(struct tipc_bearer *b)
388 {
389 	return (b && refcount_inc_not_zero(&b->refcnt));
390 }
391 
392 void tipc_bearer_put(struct tipc_bearer *b)
393 {
394 	if (b && refcount_dec_and_test(&b->refcnt))
395 		kfree_rcu(b, rcu);
396 }
397 
398 /**
399  * bearer_disable - disable this bearer
400  * @net: the applicable net namespace
401  * @b: the bearer to disable
402  *
403  * Note: This routine assumes caller holds RTNL lock.
404  */
405 static void bearer_disable(struct net *net, struct tipc_bearer *b)
406 {
407 	struct tipc_net *tn = tipc_net(net);
408 	int bearer_id = b->identity;
409 
410 	pr_info("Disabling bearer <%s>\n", b->name);
411 	clear_bit_unlock(0, &b->up);
412 	tipc_node_delete_links(net, bearer_id);
413 	b->media->disable_media(b);
414 	RCU_INIT_POINTER(b->media_ptr, NULL);
415 	if (b->disc)
416 		tipc_disc_delete(b->disc);
417 	RCU_INIT_POINTER(tn->bearer_list[bearer_id], NULL);
418 	tipc_bearer_put(b);
419 	tipc_mon_delete(net, bearer_id);
420 }
421 
422 int tipc_enable_l2_media(struct net *net, struct tipc_bearer *b,
423 			 struct nlattr *attr[])
424 {
425 	char *dev_name = strchr((const char *)b->name, ':') + 1;
426 	int hwaddr_len = b->media->hwaddr_len;
427 	u8 node_id[NODE_ID_LEN] = {0,};
428 	struct net_device *dev;
429 
430 	/* Find device with specified name */
431 	dev = dev_get_by_name(net, dev_name);
432 	if (!dev)
433 		return -ENODEV;
434 	if (tipc_mtu_bad(dev, 0)) {
435 		dev_put(dev);
436 		return -EINVAL;
437 	}
438 	if (dev == net->loopback_dev) {
439 		dev_put(dev);
440 		pr_info("Enabling <%s> not permitted\n", b->name);
441 		return -EINVAL;
442 	}
443 
444 	/* Autoconfigure own node identity if needed */
445 	if (!tipc_own_id(net) && hwaddr_len <= NODE_ID_LEN) {
446 		memcpy(node_id, dev->dev_addr, hwaddr_len);
447 		tipc_net_init(net, node_id, 0);
448 	}
449 	if (!tipc_own_id(net)) {
450 		dev_put(dev);
451 		pr_warn("Failed to obtain node identity\n");
452 		return -EINVAL;
453 	}
454 
455 	/* Associate TIPC bearer with L2 bearer */
456 	rcu_assign_pointer(b->media_ptr, dev);
457 	b->pt.dev = dev;
458 	b->pt.type = htons(ETH_P_TIPC);
459 	b->pt.func = tipc_l2_rcv_msg;
460 	dev_add_pack(&b->pt);
461 	memset(&b->bcast_addr, 0, sizeof(b->bcast_addr));
462 	memcpy(b->bcast_addr.value, dev->broadcast, hwaddr_len);
463 	b->bcast_addr.media_id = b->media->type_id;
464 	b->bcast_addr.broadcast = TIPC_BROADCAST_SUPPORT;
465 	b->mtu = dev->mtu;
466 	b->media->raw2addr(b, &b->addr, (const char *)dev->dev_addr);
467 	rcu_assign_pointer(dev->tipc_ptr, b);
468 	return 0;
469 }
470 
471 /* tipc_disable_l2_media - detach TIPC bearer from an L2 interface
472  * @b: the target bearer
473  *
474  * Mark L2 bearer as inactive so that incoming buffers are thrown away
475  */
476 void tipc_disable_l2_media(struct tipc_bearer *b)
477 {
478 	struct net_device *dev;
479 
480 	dev = (struct net_device *)rtnl_dereference(b->media_ptr);
481 	dev_remove_pack(&b->pt);
482 	RCU_INIT_POINTER(dev->tipc_ptr, NULL);
483 	synchronize_net();
484 	dev_put(dev);
485 }
486 
487 /**
488  * tipc_l2_send_msg - send a TIPC packet out over an L2 interface
489  * @net: the associated network namespace
490  * @skb: the packet to be sent
491  * @b: the bearer through which the packet is to be sent
492  * @dest: peer destination address
493  */
494 int tipc_l2_send_msg(struct net *net, struct sk_buff *skb,
495 		     struct tipc_bearer *b, struct tipc_media_addr *dest)
496 {
497 	struct net_device *dev;
498 	int delta;
499 
500 	dev = (struct net_device *)rcu_dereference(b->media_ptr);
501 	if (!dev)
502 		return 0;
503 
504 	delta = SKB_DATA_ALIGN(dev->hard_header_len - skb_headroom(skb));
505 	if ((delta > 0) && pskb_expand_head(skb, delta, 0, GFP_ATOMIC)) {
506 		kfree_skb(skb);
507 		return 0;
508 	}
509 	skb_reset_network_header(skb);
510 	skb->dev = dev;
511 	skb->protocol = htons(ETH_P_TIPC);
512 	dev_hard_header(skb, dev, ETH_P_TIPC, dest->value,
513 			dev->dev_addr, skb->len);
514 	dev_queue_xmit(skb);
515 	return 0;
516 }
517 
518 bool tipc_bearer_bcast_support(struct net *net, u32 bearer_id)
519 {
520 	bool supp = false;
521 	struct tipc_bearer *b;
522 
523 	rcu_read_lock();
524 	b = bearer_get(net, bearer_id);
525 	if (b)
526 		supp = (b->bcast_addr.broadcast == TIPC_BROADCAST_SUPPORT);
527 	rcu_read_unlock();
528 	return supp;
529 }
530 
531 int tipc_bearer_mtu(struct net *net, u32 bearer_id)
532 {
533 	int mtu = 0;
534 	struct tipc_bearer *b;
535 
536 	rcu_read_lock();
537 	b = rcu_dereference(tipc_net(net)->bearer_list[bearer_id]);
538 	if (b)
539 		mtu = b->mtu;
540 	rcu_read_unlock();
541 	return mtu;
542 }
543 
544 int tipc_bearer_min_mtu(struct net *net, u32 bearer_id)
545 {
546 	int mtu = TIPC_MIN_BEARER_MTU;
547 	struct tipc_bearer *b;
548 
549 	rcu_read_lock();
550 	b = bearer_get(net, bearer_id);
551 	if (b)
552 		mtu += b->encap_hlen;
553 	rcu_read_unlock();
554 	return mtu;
555 }
556 
557 /* tipc_bearer_xmit_skb - sends buffer to destination over bearer
558  */
559 void tipc_bearer_xmit_skb(struct net *net, u32 bearer_id,
560 			  struct sk_buff *skb,
561 			  struct tipc_media_addr *dest)
562 {
563 	struct tipc_msg *hdr = buf_msg(skb);
564 	struct tipc_bearer *b;
565 
566 	rcu_read_lock();
567 	b = bearer_get(net, bearer_id);
568 	if (likely(b && (test_bit(0, &b->up) || msg_is_reset(hdr)))) {
569 #ifdef CONFIG_TIPC_CRYPTO
570 		tipc_crypto_xmit(net, &skb, b, dest, NULL);
571 		if (skb)
572 #endif
573 			b->media->send_msg(net, skb, b, dest);
574 	} else {
575 		kfree_skb(skb);
576 	}
577 	rcu_read_unlock();
578 }
579 
580 /* tipc_bearer_xmit() -send buffer to destination over bearer
581  */
582 void tipc_bearer_xmit(struct net *net, u32 bearer_id,
583 		      struct sk_buff_head *xmitq,
584 		      struct tipc_media_addr *dst,
585 		      struct tipc_node *__dnode)
586 {
587 	struct tipc_bearer *b;
588 	struct sk_buff *skb, *tmp;
589 
590 	if (skb_queue_empty(xmitq))
591 		return;
592 
593 	rcu_read_lock();
594 	b = bearer_get(net, bearer_id);
595 	if (unlikely(!b))
596 		__skb_queue_purge(xmitq);
597 	skb_queue_walk_safe(xmitq, skb, tmp) {
598 		__skb_dequeue(xmitq);
599 		if (likely(test_bit(0, &b->up) || msg_is_reset(buf_msg(skb)))) {
600 #ifdef CONFIG_TIPC_CRYPTO
601 			tipc_crypto_xmit(net, &skb, b, dst, __dnode);
602 			if (skb)
603 #endif
604 				b->media->send_msg(net, skb, b, dst);
605 		} else {
606 			kfree_skb(skb);
607 		}
608 	}
609 	rcu_read_unlock();
610 }
611 
612 /* tipc_bearer_bc_xmit() - broadcast buffers to all destinations
613  */
614 void tipc_bearer_bc_xmit(struct net *net, u32 bearer_id,
615 			 struct sk_buff_head *xmitq)
616 {
617 	struct tipc_net *tn = tipc_net(net);
618 	struct tipc_media_addr *dst;
619 	int net_id = tn->net_id;
620 	struct tipc_bearer *b;
621 	struct sk_buff *skb, *tmp;
622 	struct tipc_msg *hdr;
623 
624 	rcu_read_lock();
625 	b = bearer_get(net, bearer_id);
626 	if (unlikely(!b || !test_bit(0, &b->up)))
627 		__skb_queue_purge(xmitq);
628 	skb_queue_walk_safe(xmitq, skb, tmp) {
629 		hdr = buf_msg(skb);
630 		msg_set_non_seq(hdr, 1);
631 		msg_set_mc_netid(hdr, net_id);
632 		__skb_dequeue(xmitq);
633 		dst = &b->bcast_addr;
634 #ifdef CONFIG_TIPC_CRYPTO
635 		tipc_crypto_xmit(net, &skb, b, dst, NULL);
636 		if (skb)
637 #endif
638 			b->media->send_msg(net, skb, b, dst);
639 	}
640 	rcu_read_unlock();
641 }
642 
643 /**
644  * tipc_l2_rcv_msg - handle incoming TIPC message from an interface
645  * @skb: the received message
646  * @dev: the net device that the packet was received on
647  * @pt: the packet_type structure which was used to register this handler
648  * @orig_dev: the original receive net device in case the device is a bond
649  *
650  * Accept only packets explicitly sent to this node, or broadcast packets;
651  * ignores packets sent using interface multicast, and traffic sent to other
652  * nodes (which can happen if interface is running in promiscuous mode).
653  */
654 static int tipc_l2_rcv_msg(struct sk_buff *skb, struct net_device *dev,
655 			   struct packet_type *pt, struct net_device *orig_dev)
656 {
657 	struct tipc_bearer *b;
658 
659 	rcu_read_lock();
660 	b = rcu_dereference(dev->tipc_ptr) ?:
661 		rcu_dereference(orig_dev->tipc_ptr);
662 	if (likely(b && test_bit(0, &b->up) &&
663 		   (skb->pkt_type <= PACKET_MULTICAST))) {
664 		skb_mark_not_on_list(skb);
665 		TIPC_SKB_CB(skb)->flags = 0;
666 		tipc_rcv(dev_net(b->pt.dev), skb, b);
667 		rcu_read_unlock();
668 		return NET_RX_SUCCESS;
669 	}
670 	rcu_read_unlock();
671 	kfree_skb(skb);
672 	return NET_RX_DROP;
673 }
674 
675 /**
676  * tipc_l2_device_event - handle device events from network device
677  * @nb: the context of the notification
678  * @evt: the type of event
679  * @ptr: the net device that the event was on
680  *
681  * This function is called by the Ethernet driver in case of link
682  * change event.
683  */
684 static int tipc_l2_device_event(struct notifier_block *nb, unsigned long evt,
685 				void *ptr)
686 {
687 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
688 	struct net *net = dev_net(dev);
689 	struct tipc_bearer *b;
690 
691 	b = rtnl_dereference(dev->tipc_ptr);
692 	if (!b)
693 		return NOTIFY_DONE;
694 
695 	trace_tipc_l2_device_event(dev, b, evt);
696 	switch (evt) {
697 	case NETDEV_CHANGE:
698 		if (netif_carrier_ok(dev) && netif_oper_up(dev)) {
699 			test_and_set_bit_lock(0, &b->up);
700 			break;
701 		}
702 		fallthrough;
703 	case NETDEV_GOING_DOWN:
704 		clear_bit_unlock(0, &b->up);
705 		tipc_reset_bearer(net, b);
706 		break;
707 	case NETDEV_UP:
708 		test_and_set_bit_lock(0, &b->up);
709 		break;
710 	case NETDEV_CHANGEMTU:
711 		if (tipc_mtu_bad(dev, 0)) {
712 			bearer_disable(net, b);
713 			break;
714 		}
715 		b->mtu = dev->mtu;
716 		tipc_reset_bearer(net, b);
717 		break;
718 	case NETDEV_CHANGEADDR:
719 		b->media->raw2addr(b, &b->addr,
720 				   (const char *)dev->dev_addr);
721 		tipc_reset_bearer(net, b);
722 		break;
723 	case NETDEV_UNREGISTER:
724 	case NETDEV_CHANGENAME:
725 		bearer_disable(net, b);
726 		break;
727 	}
728 	return NOTIFY_OK;
729 }
730 
731 static struct notifier_block notifier = {
732 	.notifier_call  = tipc_l2_device_event,
733 	.priority	= 0,
734 };
735 
736 int tipc_bearer_setup(void)
737 {
738 	return register_netdevice_notifier(&notifier);
739 }
740 
741 void tipc_bearer_cleanup(void)
742 {
743 	unregister_netdevice_notifier(&notifier);
744 }
745 
746 void tipc_bearer_stop(struct net *net)
747 {
748 	struct tipc_net *tn = net_generic(net, tipc_net_id);
749 	struct tipc_bearer *b;
750 	u32 i;
751 
752 	for (i = 0; i < MAX_BEARERS; i++) {
753 		b = rtnl_dereference(tn->bearer_list[i]);
754 		if (b) {
755 			bearer_disable(net, b);
756 			tn->bearer_list[i] = NULL;
757 		}
758 	}
759 }
760 
761 void tipc_clone_to_loopback(struct net *net, struct sk_buff_head *pkts)
762 {
763 	struct net_device *dev = net->loopback_dev;
764 	struct sk_buff *skb, *_skb;
765 	int exp;
766 
767 	skb_queue_walk(pkts, _skb) {
768 		skb = pskb_copy(_skb, GFP_ATOMIC);
769 		if (!skb)
770 			continue;
771 
772 		exp = SKB_DATA_ALIGN(dev->hard_header_len - skb_headroom(skb));
773 		if (exp > 0 && pskb_expand_head(skb, exp, 0, GFP_ATOMIC)) {
774 			kfree_skb(skb);
775 			continue;
776 		}
777 
778 		skb_reset_network_header(skb);
779 		dev_hard_header(skb, dev, ETH_P_TIPC, dev->dev_addr,
780 				dev->dev_addr, skb->len);
781 		skb->dev = dev;
782 		skb->pkt_type = PACKET_HOST;
783 		skb->ip_summed = CHECKSUM_UNNECESSARY;
784 		skb->protocol = eth_type_trans(skb, dev);
785 		netif_rx(skb);
786 	}
787 }
788 
789 static int tipc_loopback_rcv_pkt(struct sk_buff *skb, struct net_device *dev,
790 				 struct packet_type *pt, struct net_device *od)
791 {
792 	consume_skb(skb);
793 	return NET_RX_SUCCESS;
794 }
795 
796 int tipc_attach_loopback(struct net *net)
797 {
798 	struct net_device *dev = net->loopback_dev;
799 	struct tipc_net *tn = tipc_net(net);
800 
801 	if (!dev)
802 		return -ENODEV;
803 
804 	netdev_hold(dev, &tn->loopback_pt.dev_tracker, GFP_KERNEL);
805 	tn->loopback_pt.dev = dev;
806 	tn->loopback_pt.type = htons(ETH_P_TIPC);
807 	tn->loopback_pt.func = tipc_loopback_rcv_pkt;
808 	dev_add_pack(&tn->loopback_pt);
809 	return 0;
810 }
811 
812 void tipc_detach_loopback(struct net *net)
813 {
814 	struct tipc_net *tn = tipc_net(net);
815 
816 	dev_remove_pack(&tn->loopback_pt);
817 	netdev_put(net->loopback_dev, &tn->loopback_pt.dev_tracker);
818 }
819 
820 /* Caller should hold rtnl_lock to protect the bearer */
821 static int __tipc_nl_add_bearer(struct tipc_nl_msg *msg,
822 				struct tipc_bearer *bearer, int nlflags)
823 {
824 	void *hdr;
825 	struct nlattr *attrs;
826 	struct nlattr *prop;
827 
828 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
829 			  nlflags, TIPC_NL_BEARER_GET);
830 	if (!hdr)
831 		return -EMSGSIZE;
832 
833 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_BEARER);
834 	if (!attrs)
835 		goto msg_full;
836 
837 	if (nla_put_string(msg->skb, TIPC_NLA_BEARER_NAME, bearer->name))
838 		goto attr_msg_full;
839 
840 	prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_BEARER_PROP);
841 	if (!prop)
842 		goto prop_msg_full;
843 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, bearer->priority))
844 		goto prop_msg_full;
845 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, bearer->tolerance))
846 		goto prop_msg_full;
847 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bearer->max_win))
848 		goto prop_msg_full;
849 	if (bearer->media->type_id == TIPC_MEDIA_TYPE_UDP)
850 		if (nla_put_u32(msg->skb, TIPC_NLA_PROP_MTU, bearer->mtu))
851 			goto prop_msg_full;
852 
853 	nla_nest_end(msg->skb, prop);
854 
855 #ifdef CONFIG_TIPC_MEDIA_UDP
856 	if (bearer->media->type_id == TIPC_MEDIA_TYPE_UDP) {
857 		if (tipc_udp_nl_add_bearer_data(msg, bearer))
858 			goto attr_msg_full;
859 	}
860 #endif
861 
862 	nla_nest_end(msg->skb, attrs);
863 	genlmsg_end(msg->skb, hdr);
864 
865 	return 0;
866 
867 prop_msg_full:
868 	nla_nest_cancel(msg->skb, prop);
869 attr_msg_full:
870 	nla_nest_cancel(msg->skb, attrs);
871 msg_full:
872 	genlmsg_cancel(msg->skb, hdr);
873 
874 	return -EMSGSIZE;
875 }
876 
877 int tipc_nl_bearer_dump(struct sk_buff *skb, struct netlink_callback *cb)
878 {
879 	int err;
880 	int i = cb->args[0];
881 	struct tipc_bearer *bearer;
882 	struct tipc_nl_msg msg;
883 	struct net *net = sock_net(skb->sk);
884 	struct tipc_net *tn = net_generic(net, tipc_net_id);
885 
886 	if (i == MAX_BEARERS)
887 		return 0;
888 
889 	msg.skb = skb;
890 	msg.portid = NETLINK_CB(cb->skb).portid;
891 	msg.seq = cb->nlh->nlmsg_seq;
892 
893 	rtnl_lock();
894 	for (i = 0; i < MAX_BEARERS; i++) {
895 		bearer = rtnl_dereference(tn->bearer_list[i]);
896 		if (!bearer)
897 			continue;
898 
899 		err = __tipc_nl_add_bearer(&msg, bearer, NLM_F_MULTI);
900 		if (err)
901 			break;
902 	}
903 	rtnl_unlock();
904 
905 	cb->args[0] = i;
906 	return skb->len;
907 }
908 
909 int tipc_nl_bearer_get(struct sk_buff *skb, struct genl_info *info)
910 {
911 	int err;
912 	char *name;
913 	struct sk_buff *rep;
914 	struct tipc_bearer *bearer;
915 	struct tipc_nl_msg msg;
916 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
917 	struct net *net = genl_info_net(info);
918 
919 	if (!info->attrs[TIPC_NLA_BEARER])
920 		return -EINVAL;
921 
922 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
923 					  info->attrs[TIPC_NLA_BEARER],
924 					  tipc_nl_bearer_policy, info->extack);
925 	if (err)
926 		return err;
927 
928 	if (!attrs[TIPC_NLA_BEARER_NAME])
929 		return -EINVAL;
930 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
931 
932 	rep = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
933 	if (!rep)
934 		return -ENOMEM;
935 
936 	msg.skb = rep;
937 	msg.portid = info->snd_portid;
938 	msg.seq = info->snd_seq;
939 
940 	rtnl_lock();
941 	bearer = tipc_bearer_find(net, name);
942 	if (!bearer) {
943 		err = -EINVAL;
944 		NL_SET_ERR_MSG(info->extack, "Bearer not found");
945 		goto err_out;
946 	}
947 
948 	err = __tipc_nl_add_bearer(&msg, bearer, 0);
949 	if (err)
950 		goto err_out;
951 	rtnl_unlock();
952 
953 	return genlmsg_reply(rep, info);
954 err_out:
955 	rtnl_unlock();
956 	nlmsg_free(rep);
957 
958 	return err;
959 }
960 
961 int __tipc_nl_bearer_disable(struct sk_buff *skb, struct genl_info *info)
962 {
963 	int err;
964 	char *name;
965 	struct tipc_bearer *bearer;
966 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
967 	struct net *net = sock_net(skb->sk);
968 
969 	if (!info->attrs[TIPC_NLA_BEARER])
970 		return -EINVAL;
971 
972 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
973 					  info->attrs[TIPC_NLA_BEARER],
974 					  tipc_nl_bearer_policy, info->extack);
975 	if (err)
976 		return err;
977 
978 	if (!attrs[TIPC_NLA_BEARER_NAME])
979 		return -EINVAL;
980 
981 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
982 
983 	bearer = tipc_bearer_find(net, name);
984 	if (!bearer) {
985 		NL_SET_ERR_MSG(info->extack, "Bearer not found");
986 		return -EINVAL;
987 	}
988 
989 	bearer_disable(net, bearer);
990 
991 	return 0;
992 }
993 
994 int tipc_nl_bearer_disable(struct sk_buff *skb, struct genl_info *info)
995 {
996 	int err;
997 
998 	rtnl_lock();
999 	err = __tipc_nl_bearer_disable(skb, info);
1000 	rtnl_unlock();
1001 
1002 	return err;
1003 }
1004 
1005 int __tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info)
1006 {
1007 	int err;
1008 	char *bearer;
1009 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
1010 	struct net *net = sock_net(skb->sk);
1011 	u32 domain = 0;
1012 	u32 prio;
1013 
1014 	prio = TIPC_MEDIA_LINK_PRI;
1015 
1016 	if (!info->attrs[TIPC_NLA_BEARER])
1017 		return -EINVAL;
1018 
1019 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
1020 					  info->attrs[TIPC_NLA_BEARER],
1021 					  tipc_nl_bearer_policy, info->extack);
1022 	if (err)
1023 		return err;
1024 
1025 	if (!attrs[TIPC_NLA_BEARER_NAME])
1026 		return -EINVAL;
1027 
1028 	bearer = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
1029 
1030 	if (attrs[TIPC_NLA_BEARER_DOMAIN])
1031 		domain = nla_get_u32(attrs[TIPC_NLA_BEARER_DOMAIN]);
1032 
1033 	if (attrs[TIPC_NLA_BEARER_PROP]) {
1034 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
1035 
1036 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_BEARER_PROP],
1037 					      props);
1038 		if (err)
1039 			return err;
1040 
1041 		if (props[TIPC_NLA_PROP_PRIO])
1042 			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1043 	}
1044 
1045 	return tipc_enable_bearer(net, bearer, domain, prio, attrs,
1046 				  info->extack);
1047 }
1048 
1049 int tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info)
1050 {
1051 	int err;
1052 
1053 	rtnl_lock();
1054 	err = __tipc_nl_bearer_enable(skb, info);
1055 	rtnl_unlock();
1056 
1057 	return err;
1058 }
1059 
1060 int tipc_nl_bearer_add(struct sk_buff *skb, struct genl_info *info)
1061 {
1062 	int err;
1063 	char *name;
1064 	struct tipc_bearer *b;
1065 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
1066 	struct net *net = sock_net(skb->sk);
1067 
1068 	if (!info->attrs[TIPC_NLA_BEARER])
1069 		return -EINVAL;
1070 
1071 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
1072 					  info->attrs[TIPC_NLA_BEARER],
1073 					  tipc_nl_bearer_policy, info->extack);
1074 	if (err)
1075 		return err;
1076 
1077 	if (!attrs[TIPC_NLA_BEARER_NAME])
1078 		return -EINVAL;
1079 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
1080 
1081 	rtnl_lock();
1082 	b = tipc_bearer_find(net, name);
1083 	if (!b) {
1084 		rtnl_unlock();
1085 		NL_SET_ERR_MSG(info->extack, "Bearer not found");
1086 		return -EINVAL;
1087 	}
1088 
1089 #ifdef CONFIG_TIPC_MEDIA_UDP
1090 	if (attrs[TIPC_NLA_BEARER_UDP_OPTS]) {
1091 		err = tipc_udp_nl_bearer_add(b,
1092 					     attrs[TIPC_NLA_BEARER_UDP_OPTS]);
1093 		if (err) {
1094 			rtnl_unlock();
1095 			return err;
1096 		}
1097 	}
1098 #endif
1099 	rtnl_unlock();
1100 
1101 	return 0;
1102 }
1103 
1104 int __tipc_nl_bearer_set(struct sk_buff *skb, struct genl_info *info)
1105 {
1106 	struct tipc_bearer *b;
1107 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
1108 	struct net *net = sock_net(skb->sk);
1109 	char *name;
1110 	int err;
1111 
1112 	if (!info->attrs[TIPC_NLA_BEARER])
1113 		return -EINVAL;
1114 
1115 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
1116 					  info->attrs[TIPC_NLA_BEARER],
1117 					  tipc_nl_bearer_policy, info->extack);
1118 	if (err)
1119 		return err;
1120 
1121 	if (!attrs[TIPC_NLA_BEARER_NAME])
1122 		return -EINVAL;
1123 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
1124 
1125 	b = tipc_bearer_find(net, name);
1126 	if (!b) {
1127 		NL_SET_ERR_MSG(info->extack, "Bearer not found");
1128 		return -EINVAL;
1129 	}
1130 
1131 	if (attrs[TIPC_NLA_BEARER_PROP]) {
1132 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
1133 
1134 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_BEARER_PROP],
1135 					      props);
1136 		if (err)
1137 			return err;
1138 
1139 		if (props[TIPC_NLA_PROP_TOL]) {
1140 			b->tolerance = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1141 			tipc_node_apply_property(net, b, TIPC_NLA_PROP_TOL);
1142 		}
1143 		if (props[TIPC_NLA_PROP_PRIO])
1144 			b->priority = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1145 		if (props[TIPC_NLA_PROP_WIN])
1146 			b->max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1147 		if (props[TIPC_NLA_PROP_MTU]) {
1148 			if (b->media->type_id != TIPC_MEDIA_TYPE_UDP) {
1149 				NL_SET_ERR_MSG(info->extack,
1150 					       "MTU property is unsupported");
1151 				return -EINVAL;
1152 			}
1153 #ifdef CONFIG_TIPC_MEDIA_UDP
1154 			if (nla_get_u32(props[TIPC_NLA_PROP_MTU]) <
1155 			    b->encap_hlen + TIPC_MIN_BEARER_MTU) {
1156 				NL_SET_ERR_MSG(info->extack,
1157 					       "MTU value is out-of-range");
1158 				return -EINVAL;
1159 			}
1160 			b->mtu = nla_get_u32(props[TIPC_NLA_PROP_MTU]);
1161 			tipc_node_apply_property(net, b, TIPC_NLA_PROP_MTU);
1162 #endif
1163 		}
1164 	}
1165 
1166 	return 0;
1167 }
1168 
1169 int tipc_nl_bearer_set(struct sk_buff *skb, struct genl_info *info)
1170 {
1171 	int err;
1172 
1173 	rtnl_lock();
1174 	err = __tipc_nl_bearer_set(skb, info);
1175 	rtnl_unlock();
1176 
1177 	return err;
1178 }
1179 
1180 static int __tipc_nl_add_media(struct tipc_nl_msg *msg,
1181 			       struct tipc_media *media, int nlflags)
1182 {
1183 	void *hdr;
1184 	struct nlattr *attrs;
1185 	struct nlattr *prop;
1186 
1187 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1188 			  nlflags, TIPC_NL_MEDIA_GET);
1189 	if (!hdr)
1190 		return -EMSGSIZE;
1191 
1192 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_MEDIA);
1193 	if (!attrs)
1194 		goto msg_full;
1195 
1196 	if (nla_put_string(msg->skb, TIPC_NLA_MEDIA_NAME, media->name))
1197 		goto attr_msg_full;
1198 
1199 	prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_MEDIA_PROP);
1200 	if (!prop)
1201 		goto prop_msg_full;
1202 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, media->priority))
1203 		goto prop_msg_full;
1204 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, media->tolerance))
1205 		goto prop_msg_full;
1206 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, media->max_win))
1207 		goto prop_msg_full;
1208 	if (media->type_id == TIPC_MEDIA_TYPE_UDP)
1209 		if (nla_put_u32(msg->skb, TIPC_NLA_PROP_MTU, media->mtu))
1210 			goto prop_msg_full;
1211 
1212 	nla_nest_end(msg->skb, prop);
1213 	nla_nest_end(msg->skb, attrs);
1214 	genlmsg_end(msg->skb, hdr);
1215 
1216 	return 0;
1217 
1218 prop_msg_full:
1219 	nla_nest_cancel(msg->skb, prop);
1220 attr_msg_full:
1221 	nla_nest_cancel(msg->skb, attrs);
1222 msg_full:
1223 	genlmsg_cancel(msg->skb, hdr);
1224 
1225 	return -EMSGSIZE;
1226 }
1227 
1228 int tipc_nl_media_dump(struct sk_buff *skb, struct netlink_callback *cb)
1229 {
1230 	int err;
1231 	int i = cb->args[0];
1232 	struct tipc_nl_msg msg;
1233 
1234 	if (i == MAX_MEDIA)
1235 		return 0;
1236 
1237 	msg.skb = skb;
1238 	msg.portid = NETLINK_CB(cb->skb).portid;
1239 	msg.seq = cb->nlh->nlmsg_seq;
1240 
1241 	rtnl_lock();
1242 	for (; media_info_array[i] != NULL; i++) {
1243 		err = __tipc_nl_add_media(&msg, media_info_array[i],
1244 					  NLM_F_MULTI);
1245 		if (err)
1246 			break;
1247 	}
1248 	rtnl_unlock();
1249 
1250 	cb->args[0] = i;
1251 	return skb->len;
1252 }
1253 
1254 int tipc_nl_media_get(struct sk_buff *skb, struct genl_info *info)
1255 {
1256 	int err;
1257 	char *name;
1258 	struct tipc_nl_msg msg;
1259 	struct tipc_media *media;
1260 	struct sk_buff *rep;
1261 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
1262 
1263 	if (!info->attrs[TIPC_NLA_MEDIA])
1264 		return -EINVAL;
1265 
1266 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_MEDIA_MAX,
1267 					  info->attrs[TIPC_NLA_MEDIA],
1268 					  tipc_nl_media_policy, info->extack);
1269 	if (err)
1270 		return err;
1271 
1272 	if (!attrs[TIPC_NLA_MEDIA_NAME])
1273 		return -EINVAL;
1274 	name = nla_data(attrs[TIPC_NLA_MEDIA_NAME]);
1275 
1276 	rep = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
1277 	if (!rep)
1278 		return -ENOMEM;
1279 
1280 	msg.skb = rep;
1281 	msg.portid = info->snd_portid;
1282 	msg.seq = info->snd_seq;
1283 
1284 	rtnl_lock();
1285 	media = tipc_media_find(name);
1286 	if (!media) {
1287 		NL_SET_ERR_MSG(info->extack, "Media not found");
1288 		err = -EINVAL;
1289 		goto err_out;
1290 	}
1291 
1292 	err = __tipc_nl_add_media(&msg, media, 0);
1293 	if (err)
1294 		goto err_out;
1295 	rtnl_unlock();
1296 
1297 	return genlmsg_reply(rep, info);
1298 err_out:
1299 	rtnl_unlock();
1300 	nlmsg_free(rep);
1301 
1302 	return err;
1303 }
1304 
1305 int __tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info)
1306 {
1307 	int err;
1308 	char *name;
1309 	struct tipc_media *m;
1310 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
1311 
1312 	if (!info->attrs[TIPC_NLA_MEDIA])
1313 		return -EINVAL;
1314 
1315 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_MEDIA_MAX,
1316 					  info->attrs[TIPC_NLA_MEDIA],
1317 					  tipc_nl_media_policy, info->extack);
1318 
1319 	if (!attrs[TIPC_NLA_MEDIA_NAME])
1320 		return -EINVAL;
1321 	name = nla_data(attrs[TIPC_NLA_MEDIA_NAME]);
1322 
1323 	m = tipc_media_find(name);
1324 	if (!m) {
1325 		NL_SET_ERR_MSG(info->extack, "Media not found");
1326 		return -EINVAL;
1327 	}
1328 	if (attrs[TIPC_NLA_MEDIA_PROP]) {
1329 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
1330 
1331 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_MEDIA_PROP],
1332 					      props);
1333 		if (err)
1334 			return err;
1335 
1336 		if (props[TIPC_NLA_PROP_TOL])
1337 			m->tolerance = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1338 		if (props[TIPC_NLA_PROP_PRIO])
1339 			m->priority = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1340 		if (props[TIPC_NLA_PROP_WIN])
1341 			m->max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1342 		if (props[TIPC_NLA_PROP_MTU]) {
1343 			if (m->type_id != TIPC_MEDIA_TYPE_UDP) {
1344 				NL_SET_ERR_MSG(info->extack,
1345 					       "MTU property is unsupported");
1346 				return -EINVAL;
1347 			}
1348 #ifdef CONFIG_TIPC_MEDIA_UDP
1349 			if (tipc_udp_mtu_bad(nla_get_u32
1350 					     (props[TIPC_NLA_PROP_MTU]))) {
1351 				NL_SET_ERR_MSG(info->extack,
1352 					       "MTU value is out-of-range");
1353 				return -EINVAL;
1354 			}
1355 			m->mtu = nla_get_u32(props[TIPC_NLA_PROP_MTU]);
1356 #endif
1357 		}
1358 	}
1359 
1360 	return 0;
1361 }
1362 
1363 int tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info)
1364 {
1365 	int err;
1366 
1367 	rtnl_lock();
1368 	err = __tipc_nl_media_set(skb, info);
1369 	rtnl_unlock();
1370 
1371 	return err;
1372 }
1373