xref: /linux/net/tipc/bearer.c (revision 0d240e7811c4ec1965760ee4643b5bbc9cfacbb3)
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 
46 #define MAX_ADDR_STR 60
47 
48 static struct tipc_media * const media_info_array[] = {
49 	&eth_media_info,
50 #ifdef CONFIG_TIPC_MEDIA_IB
51 	&ib_media_info,
52 #endif
53 #ifdef CONFIG_TIPC_MEDIA_UDP
54 	&udp_media_info,
55 #endif
56 	NULL
57 };
58 
59 static void bearer_disable(struct net *net, struct tipc_bearer *b);
60 
61 /**
62  * tipc_media_find - locates specified media object by name
63  */
64 struct tipc_media *tipc_media_find(const char *name)
65 {
66 	u32 i;
67 
68 	for (i = 0; media_info_array[i] != NULL; i++) {
69 		if (!strcmp(media_info_array[i]->name, name))
70 			break;
71 	}
72 	return media_info_array[i];
73 }
74 
75 /**
76  * media_find_id - locates specified media object by type identifier
77  */
78 static struct tipc_media *media_find_id(u8 type)
79 {
80 	u32 i;
81 
82 	for (i = 0; media_info_array[i] != NULL; i++) {
83 		if (media_info_array[i]->type_id == type)
84 			break;
85 	}
86 	return media_info_array[i];
87 }
88 
89 /**
90  * tipc_media_addr_printf - record media address in print buffer
91  */
92 void tipc_media_addr_printf(char *buf, int len, struct tipc_media_addr *a)
93 {
94 	char addr_str[MAX_ADDR_STR];
95 	struct tipc_media *m;
96 	int ret;
97 
98 	m = media_find_id(a->media_id);
99 
100 	if (m && !m->addr2str(a, addr_str, sizeof(addr_str)))
101 		ret = scnprintf(buf, len, "%s(%s)", m->name, addr_str);
102 	else {
103 		u32 i;
104 
105 		ret = scnprintf(buf, len, "UNKNOWN(%u)", a->media_id);
106 		for (i = 0; i < sizeof(a->value); i++)
107 			ret += scnprintf(buf - ret, len + ret,
108 					    "-%02x", a->value[i]);
109 	}
110 }
111 
112 /**
113  * bearer_name_validate - validate & (optionally) deconstruct bearer name
114  * @name: ptr to bearer name string
115  * @name_parts: ptr to area for bearer name components (or NULL if not needed)
116  *
117  * Returns 1 if bearer name is valid, otherwise 0.
118  */
119 static int bearer_name_validate(const char *name,
120 				struct tipc_bearer_names *name_parts)
121 {
122 	char name_copy[TIPC_MAX_BEARER_NAME];
123 	char *media_name;
124 	char *if_name;
125 	u32 media_len;
126 	u32 if_len;
127 
128 	/* copy bearer name & ensure length is OK */
129 	name_copy[TIPC_MAX_BEARER_NAME - 1] = 0;
130 	/* need above in case non-Posix strncpy() doesn't pad with nulls */
131 	strncpy(name_copy, name, TIPC_MAX_BEARER_NAME);
132 	if (name_copy[TIPC_MAX_BEARER_NAME - 1] != 0)
133 		return 0;
134 
135 	/* ensure all component parts of bearer name are present */
136 	media_name = name_copy;
137 	if_name = strchr(media_name, ':');
138 	if (if_name == NULL)
139 		return 0;
140 	*(if_name++) = 0;
141 	media_len = if_name - media_name;
142 	if_len = strlen(if_name) + 1;
143 
144 	/* validate component parts of bearer name */
145 	if ((media_len <= 1) || (media_len > TIPC_MAX_MEDIA_NAME) ||
146 	    (if_len <= 1) || (if_len > TIPC_MAX_IF_NAME))
147 		return 0;
148 
149 	/* return bearer name components, if necessary */
150 	if (name_parts) {
151 		strcpy(name_parts->media_name, media_name);
152 		strcpy(name_parts->if_name, if_name);
153 	}
154 	return 1;
155 }
156 
157 /**
158  * tipc_bearer_find - locates bearer object with matching bearer name
159  */
160 struct tipc_bearer *tipc_bearer_find(struct net *net, const char *name)
161 {
162 	struct tipc_net *tn = net_generic(net, tipc_net_id);
163 	struct tipc_bearer *b;
164 	u32 i;
165 
166 	for (i = 0; i < MAX_BEARERS; i++) {
167 		b = rtnl_dereference(tn->bearer_list[i]);
168 		if (b && (!strcmp(b->name, name)))
169 			return b;
170 	}
171 	return NULL;
172 }
173 
174 void tipc_bearer_add_dest(struct net *net, u32 bearer_id, u32 dest)
175 {
176 	struct tipc_net *tn = net_generic(net, tipc_net_id);
177 	struct tipc_bearer *b;
178 
179 	rcu_read_lock();
180 	b = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
181 	if (b)
182 		tipc_disc_add_dest(b->link_req);
183 	rcu_read_unlock();
184 }
185 
186 void tipc_bearer_remove_dest(struct net *net, u32 bearer_id, u32 dest)
187 {
188 	struct tipc_net *tn = net_generic(net, tipc_net_id);
189 	struct tipc_bearer *b;
190 
191 	rcu_read_lock();
192 	b = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
193 	if (b)
194 		tipc_disc_remove_dest(b->link_req);
195 	rcu_read_unlock();
196 }
197 
198 /**
199  * tipc_enable_bearer - enable bearer with the given name
200  */
201 static int tipc_enable_bearer(struct net *net, const char *name,
202 			      u32 disc_domain, u32 priority,
203 			      struct nlattr *attr[])
204 {
205 	struct tipc_net *tn = net_generic(net, tipc_net_id);
206 	struct tipc_bearer *b;
207 	struct tipc_media *m;
208 	struct tipc_bearer_names b_names;
209 	struct sk_buff *skb;
210 	char addr_string[16];
211 	u32 bearer_id;
212 	u32 with_this_prio;
213 	u32 i;
214 	int res = -EINVAL;
215 
216 	if (!tn->own_addr) {
217 		pr_warn("Bearer <%s> rejected, not supported in standalone mode\n",
218 			name);
219 		return -ENOPROTOOPT;
220 	}
221 	if (!bearer_name_validate(name, &b_names)) {
222 		pr_warn("Bearer <%s> rejected, illegal name\n", name);
223 		return -EINVAL;
224 	}
225 	if (tipc_addr_domain_valid(disc_domain) &&
226 	    (disc_domain != tn->own_addr)) {
227 		if (tipc_in_scope(disc_domain, tn->own_addr)) {
228 			disc_domain = tn->own_addr & TIPC_CLUSTER_MASK;
229 			res = 0;   /* accept any node in own cluster */
230 		} else if (in_own_cluster_exact(net, disc_domain))
231 			res = 0;   /* accept specified node in own cluster */
232 	}
233 	if (res) {
234 		pr_warn("Bearer <%s> rejected, illegal discovery domain\n",
235 			name);
236 		return -EINVAL;
237 	}
238 	if ((priority > TIPC_MAX_LINK_PRI) &&
239 	    (priority != TIPC_MEDIA_LINK_PRI)) {
240 		pr_warn("Bearer <%s> rejected, illegal priority\n", name);
241 		return -EINVAL;
242 	}
243 
244 	m = tipc_media_find(b_names.media_name);
245 	if (!m) {
246 		pr_warn("Bearer <%s> rejected, media <%s> not registered\n",
247 			name, b_names.media_name);
248 		return -EINVAL;
249 	}
250 
251 	if (priority == TIPC_MEDIA_LINK_PRI)
252 		priority = m->priority;
253 
254 restart:
255 	bearer_id = MAX_BEARERS;
256 	with_this_prio = 1;
257 	for (i = MAX_BEARERS; i-- != 0; ) {
258 		b = rtnl_dereference(tn->bearer_list[i]);
259 		if (!b) {
260 			bearer_id = i;
261 			continue;
262 		}
263 		if (!strcmp(name, b->name)) {
264 			pr_warn("Bearer <%s> rejected, already enabled\n",
265 				name);
266 			return -EINVAL;
267 		}
268 		if ((b->priority == priority) &&
269 		    (++with_this_prio > 2)) {
270 			if (priority-- == 0) {
271 				pr_warn("Bearer <%s> rejected, duplicate priority\n",
272 					name);
273 				return -EINVAL;
274 			}
275 			pr_warn("Bearer <%s> priority adjustment required %u->%u\n",
276 				name, priority + 1, priority);
277 			goto restart;
278 		}
279 	}
280 	if (bearer_id >= MAX_BEARERS) {
281 		pr_warn("Bearer <%s> rejected, bearer limit reached (%u)\n",
282 			name, MAX_BEARERS);
283 		return -EINVAL;
284 	}
285 
286 	b = kzalloc(sizeof(*b), GFP_ATOMIC);
287 	if (!b)
288 		return -ENOMEM;
289 
290 	strcpy(b->name, name);
291 	b->media = m;
292 	res = m->enable_media(net, b, attr);
293 	if (res) {
294 		pr_warn("Bearer <%s> rejected, enable failure (%d)\n",
295 			name, -res);
296 		return -EINVAL;
297 	}
298 
299 	b->identity = bearer_id;
300 	b->tolerance = m->tolerance;
301 	b->window = m->window;
302 	b->domain = disc_domain;
303 	b->net_plane = bearer_id + 'A';
304 	b->priority = priority;
305 
306 	res = tipc_disc_create(net, b, &b->bcast_addr, &skb);
307 	if (res) {
308 		bearer_disable(net, b);
309 		pr_warn("Bearer <%s> rejected, discovery object creation failed\n",
310 			name);
311 		return -EINVAL;
312 	}
313 
314 	rcu_assign_pointer(tn->bearer_list[bearer_id], b);
315 	if (skb)
316 		tipc_bearer_xmit_skb(net, bearer_id, skb, &b->bcast_addr);
317 
318 	if (tipc_mon_create(net, bearer_id))
319 		return -ENOMEM;
320 
321 	pr_info("Enabled bearer <%s>, discovery domain %s, priority %u\n",
322 		name,
323 		tipc_addr_string_fill(addr_string, disc_domain), priority);
324 	return res;
325 }
326 
327 /**
328  * tipc_reset_bearer - Reset all links established over this bearer
329  */
330 static int tipc_reset_bearer(struct net *net, struct tipc_bearer *b)
331 {
332 	pr_info("Resetting bearer <%s>\n", b->name);
333 	tipc_node_delete_links(net, b->identity);
334 	tipc_disc_reset(net, b);
335 	return 0;
336 }
337 
338 /**
339  * bearer_disable
340  *
341  * Note: This routine assumes caller holds RTNL lock.
342  */
343 static void bearer_disable(struct net *net, struct tipc_bearer *b)
344 {
345 	struct tipc_net *tn = tipc_net(net);
346 	int bearer_id = b->identity;
347 
348 	pr_info("Disabling bearer <%s>\n", b->name);
349 	b->media->disable_media(b);
350 	tipc_node_delete_links(net, bearer_id);
351 	RCU_INIT_POINTER(b->media_ptr, NULL);
352 	if (b->link_req)
353 		tipc_disc_delete(b->link_req);
354 	RCU_INIT_POINTER(tn->bearer_list[bearer_id], NULL);
355 	kfree_rcu(b, rcu);
356 	tipc_mon_delete(net, bearer_id);
357 }
358 
359 int tipc_enable_l2_media(struct net *net, struct tipc_bearer *b,
360 			 struct nlattr *attr[])
361 {
362 	struct net_device *dev;
363 	char *driver_name = strchr((const char *)b->name, ':') + 1;
364 
365 	/* Find device with specified name */
366 	dev = dev_get_by_name(net, driver_name);
367 	if (!dev)
368 		return -ENODEV;
369 
370 	/* Associate TIPC bearer with L2 bearer */
371 	rcu_assign_pointer(b->media_ptr, dev);
372 	memset(&b->bcast_addr, 0, sizeof(b->bcast_addr));
373 	memcpy(b->bcast_addr.value, dev->broadcast, b->media->hwaddr_len);
374 	b->bcast_addr.media_id = b->media->type_id;
375 	b->bcast_addr.broadcast = 1;
376 	b->mtu = dev->mtu;
377 	b->media->raw2addr(b, &b->addr, (char *)dev->dev_addr);
378 	rcu_assign_pointer(dev->tipc_ptr, b);
379 	return 0;
380 }
381 
382 /* tipc_disable_l2_media - detach TIPC bearer from an L2 interface
383  *
384  * Mark L2 bearer as inactive so that incoming buffers are thrown away
385  */
386 void tipc_disable_l2_media(struct tipc_bearer *b)
387 {
388 	struct net_device *dev;
389 
390 	dev = (struct net_device *)rtnl_dereference(b->media_ptr);
391 	RCU_INIT_POINTER(dev->tipc_ptr, NULL);
392 	synchronize_net();
393 	dev_put(dev);
394 }
395 
396 /**
397  * tipc_l2_send_msg - send a TIPC packet out over an L2 interface
398  * @skb: the packet to be sent
399  * @b: the bearer through which the packet is to be sent
400  * @dest: peer destination address
401  */
402 int tipc_l2_send_msg(struct net *net, struct sk_buff *skb,
403 		     struct tipc_bearer *b, struct tipc_media_addr *dest)
404 {
405 	struct net_device *dev;
406 	int delta;
407 	void *tipc_ptr;
408 
409 	dev = (struct net_device *)rcu_dereference_rtnl(b->media_ptr);
410 	if (!dev)
411 		return 0;
412 
413 	/* Send RESET message even if bearer is detached from device */
414 	tipc_ptr = rtnl_dereference(dev->tipc_ptr);
415 	if (unlikely(!tipc_ptr && !msg_is_reset(buf_msg(skb))))
416 		goto drop;
417 
418 	delta = dev->hard_header_len - skb_headroom(skb);
419 	if ((delta > 0) &&
420 	    pskb_expand_head(skb, SKB_DATA_ALIGN(delta), 0, GFP_ATOMIC))
421 		goto drop;
422 
423 	skb_reset_network_header(skb);
424 	skb->dev = dev;
425 	skb->protocol = htons(ETH_P_TIPC);
426 	dev_hard_header(skb, dev, ETH_P_TIPC, dest->value,
427 			dev->dev_addr, skb->len);
428 	dev_queue_xmit(skb);
429 	return 0;
430 drop:
431 	kfree_skb(skb);
432 	return 0;
433 }
434 
435 int tipc_bearer_mtu(struct net *net, u32 bearer_id)
436 {
437 	int mtu = 0;
438 	struct tipc_bearer *b;
439 
440 	rcu_read_lock();
441 	b = rcu_dereference_rtnl(tipc_net(net)->bearer_list[bearer_id]);
442 	if (b)
443 		mtu = b->mtu;
444 	rcu_read_unlock();
445 	return mtu;
446 }
447 
448 /* tipc_bearer_xmit_skb - sends buffer to destination over bearer
449  */
450 void tipc_bearer_xmit_skb(struct net *net, u32 bearer_id,
451 			  struct sk_buff *skb,
452 			  struct tipc_media_addr *dest)
453 {
454 	struct tipc_net *tn = tipc_net(net);
455 	struct tipc_bearer *b;
456 
457 	rcu_read_lock();
458 	b = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
459 	if (likely(b))
460 		b->media->send_msg(net, skb, b, dest);
461 	else
462 		kfree_skb(skb);
463 	rcu_read_unlock();
464 }
465 
466 /* tipc_bearer_xmit() -send buffer to destination over bearer
467  */
468 void tipc_bearer_xmit(struct net *net, u32 bearer_id,
469 		      struct sk_buff_head *xmitq,
470 		      struct tipc_media_addr *dst)
471 {
472 	struct tipc_net *tn = net_generic(net, tipc_net_id);
473 	struct tipc_bearer *b;
474 	struct sk_buff *skb, *tmp;
475 
476 	if (skb_queue_empty(xmitq))
477 		return;
478 
479 	rcu_read_lock();
480 	b = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
481 	if (unlikely(!b))
482 		__skb_queue_purge(xmitq);
483 	skb_queue_walk_safe(xmitq, skb, tmp) {
484 		__skb_dequeue(xmitq);
485 		b->media->send_msg(net, skb, b, dst);
486 	}
487 	rcu_read_unlock();
488 }
489 
490 /* tipc_bearer_bc_xmit() - broadcast buffers to all destinations
491  */
492 void tipc_bearer_bc_xmit(struct net *net, u32 bearer_id,
493 			 struct sk_buff_head *xmitq)
494 {
495 	struct tipc_net *tn = tipc_net(net);
496 	int net_id = tn->net_id;
497 	struct tipc_bearer *b;
498 	struct sk_buff *skb, *tmp;
499 	struct tipc_msg *hdr;
500 
501 	rcu_read_lock();
502 	b = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
503 	if (unlikely(!b))
504 		__skb_queue_purge(xmitq);
505 	skb_queue_walk_safe(xmitq, skb, tmp) {
506 		hdr = buf_msg(skb);
507 		msg_set_non_seq(hdr, 1);
508 		msg_set_mc_netid(hdr, net_id);
509 		__skb_dequeue(xmitq);
510 		b->media->send_msg(net, skb, b, &b->bcast_addr);
511 	}
512 	rcu_read_unlock();
513 }
514 
515 /**
516  * tipc_l2_rcv_msg - handle incoming TIPC message from an interface
517  * @buf: the received packet
518  * @dev: the net device that the packet was received on
519  * @pt: the packet_type structure which was used to register this handler
520  * @orig_dev: the original receive net device in case the device is a bond
521  *
522  * Accept only packets explicitly sent to this node, or broadcast packets;
523  * ignores packets sent using interface multicast, and traffic sent to other
524  * nodes (which can happen if interface is running in promiscuous mode).
525  */
526 static int tipc_l2_rcv_msg(struct sk_buff *skb, struct net_device *dev,
527 			   struct packet_type *pt, struct net_device *orig_dev)
528 {
529 	struct tipc_bearer *b;
530 
531 	rcu_read_lock();
532 	b = rcu_dereference_rtnl(dev->tipc_ptr);
533 	if (likely(b && (skb->pkt_type <= PACKET_BROADCAST))) {
534 		skb->next = NULL;
535 		tipc_rcv(dev_net(dev), skb, b);
536 		rcu_read_unlock();
537 		return NET_RX_SUCCESS;
538 	}
539 	rcu_read_unlock();
540 	kfree_skb(skb);
541 	return NET_RX_DROP;
542 }
543 
544 /**
545  * tipc_l2_device_event - handle device events from network device
546  * @nb: the context of the notification
547  * @evt: the type of event
548  * @ptr: the net device that the event was on
549  *
550  * This function is called by the Ethernet driver in case of link
551  * change event.
552  */
553 static int tipc_l2_device_event(struct notifier_block *nb, unsigned long evt,
554 				void *ptr)
555 {
556 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
557 	struct net *net = dev_net(dev);
558 	struct tipc_net *tn = tipc_net(net);
559 	struct tipc_bearer *b;
560 	int i;
561 
562 	b = rtnl_dereference(dev->tipc_ptr);
563 	if (!b) {
564 		for (i = 0; i < MAX_BEARERS; b = NULL, i++) {
565 			b = rtnl_dereference(tn->bearer_list[i]);
566 			if (b && (b->media_ptr == dev))
567 				break;
568 		}
569 	}
570 	if (!b)
571 		return NOTIFY_DONE;
572 
573 	b->mtu = dev->mtu;
574 
575 	switch (evt) {
576 	case NETDEV_CHANGE:
577 		if (netif_carrier_ok(dev))
578 			break;
579 	case NETDEV_UP:
580 		rcu_assign_pointer(dev->tipc_ptr, b);
581 		break;
582 	case NETDEV_GOING_DOWN:
583 		RCU_INIT_POINTER(dev->tipc_ptr, NULL);
584 		synchronize_net();
585 		tipc_reset_bearer(net, b);
586 		break;
587 	case NETDEV_CHANGEMTU:
588 		tipc_reset_bearer(net, b);
589 		break;
590 	case NETDEV_CHANGEADDR:
591 		b->media->raw2addr(b, &b->addr,
592 				   (char *)dev->dev_addr);
593 		tipc_reset_bearer(net, b);
594 		break;
595 	case NETDEV_UNREGISTER:
596 	case NETDEV_CHANGENAME:
597 		bearer_disable(dev_net(dev), b);
598 		break;
599 	}
600 	return NOTIFY_OK;
601 }
602 
603 static struct packet_type tipc_packet_type __read_mostly = {
604 	.type = htons(ETH_P_TIPC),
605 	.func = tipc_l2_rcv_msg,
606 };
607 
608 static struct notifier_block notifier = {
609 	.notifier_call  = tipc_l2_device_event,
610 	.priority	= 0,
611 };
612 
613 int tipc_bearer_setup(void)
614 {
615 	int err;
616 
617 	err = register_netdevice_notifier(&notifier);
618 	if (err)
619 		return err;
620 	dev_add_pack(&tipc_packet_type);
621 	return 0;
622 }
623 
624 void tipc_bearer_cleanup(void)
625 {
626 	unregister_netdevice_notifier(&notifier);
627 	dev_remove_pack(&tipc_packet_type);
628 }
629 
630 void tipc_bearer_stop(struct net *net)
631 {
632 	struct tipc_net *tn = net_generic(net, tipc_net_id);
633 	struct tipc_bearer *b;
634 	u32 i;
635 
636 	for (i = 0; i < MAX_BEARERS; i++) {
637 		b = rtnl_dereference(tn->bearer_list[i]);
638 		if (b) {
639 			bearer_disable(net, b);
640 			tn->bearer_list[i] = NULL;
641 		}
642 	}
643 }
644 
645 /* Caller should hold rtnl_lock to protect the bearer */
646 static int __tipc_nl_add_bearer(struct tipc_nl_msg *msg,
647 				struct tipc_bearer *bearer, int nlflags)
648 {
649 	void *hdr;
650 	struct nlattr *attrs;
651 	struct nlattr *prop;
652 
653 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
654 			  nlflags, TIPC_NL_BEARER_GET);
655 	if (!hdr)
656 		return -EMSGSIZE;
657 
658 	attrs = nla_nest_start(msg->skb, TIPC_NLA_BEARER);
659 	if (!attrs)
660 		goto msg_full;
661 
662 	if (nla_put_string(msg->skb, TIPC_NLA_BEARER_NAME, bearer->name))
663 		goto attr_msg_full;
664 
665 	prop = nla_nest_start(msg->skb, TIPC_NLA_BEARER_PROP);
666 	if (!prop)
667 		goto prop_msg_full;
668 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, bearer->priority))
669 		goto prop_msg_full;
670 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, bearer->tolerance))
671 		goto prop_msg_full;
672 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bearer->window))
673 		goto prop_msg_full;
674 
675 	nla_nest_end(msg->skb, prop);
676 	nla_nest_end(msg->skb, attrs);
677 	genlmsg_end(msg->skb, hdr);
678 
679 	return 0;
680 
681 prop_msg_full:
682 	nla_nest_cancel(msg->skb, prop);
683 attr_msg_full:
684 	nla_nest_cancel(msg->skb, attrs);
685 msg_full:
686 	genlmsg_cancel(msg->skb, hdr);
687 
688 	return -EMSGSIZE;
689 }
690 
691 int tipc_nl_bearer_dump(struct sk_buff *skb, struct netlink_callback *cb)
692 {
693 	int err;
694 	int i = cb->args[0];
695 	struct tipc_bearer *bearer;
696 	struct tipc_nl_msg msg;
697 	struct net *net = sock_net(skb->sk);
698 	struct tipc_net *tn = net_generic(net, tipc_net_id);
699 
700 	if (i == MAX_BEARERS)
701 		return 0;
702 
703 	msg.skb = skb;
704 	msg.portid = NETLINK_CB(cb->skb).portid;
705 	msg.seq = cb->nlh->nlmsg_seq;
706 
707 	rtnl_lock();
708 	for (i = 0; i < MAX_BEARERS; i++) {
709 		bearer = rtnl_dereference(tn->bearer_list[i]);
710 		if (!bearer)
711 			continue;
712 
713 		err = __tipc_nl_add_bearer(&msg, bearer, NLM_F_MULTI);
714 		if (err)
715 			break;
716 	}
717 	rtnl_unlock();
718 
719 	cb->args[0] = i;
720 	return skb->len;
721 }
722 
723 int tipc_nl_bearer_get(struct sk_buff *skb, struct genl_info *info)
724 {
725 	int err;
726 	char *name;
727 	struct sk_buff *rep;
728 	struct tipc_bearer *bearer;
729 	struct tipc_nl_msg msg;
730 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
731 	struct net *net = genl_info_net(info);
732 
733 	if (!info->attrs[TIPC_NLA_BEARER])
734 		return -EINVAL;
735 
736 	err = nla_parse_nested(attrs, TIPC_NLA_BEARER_MAX,
737 			       info->attrs[TIPC_NLA_BEARER],
738 			       tipc_nl_bearer_policy);
739 	if (err)
740 		return err;
741 
742 	if (!attrs[TIPC_NLA_BEARER_NAME])
743 		return -EINVAL;
744 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
745 
746 	rep = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
747 	if (!rep)
748 		return -ENOMEM;
749 
750 	msg.skb = rep;
751 	msg.portid = info->snd_portid;
752 	msg.seq = info->snd_seq;
753 
754 	rtnl_lock();
755 	bearer = tipc_bearer_find(net, name);
756 	if (!bearer) {
757 		err = -EINVAL;
758 		goto err_out;
759 	}
760 
761 	err = __tipc_nl_add_bearer(&msg, bearer, 0);
762 	if (err)
763 		goto err_out;
764 	rtnl_unlock();
765 
766 	return genlmsg_reply(rep, info);
767 err_out:
768 	rtnl_unlock();
769 	nlmsg_free(rep);
770 
771 	return err;
772 }
773 
774 int tipc_nl_bearer_disable(struct sk_buff *skb, struct genl_info *info)
775 {
776 	int err;
777 	char *name;
778 	struct tipc_bearer *bearer;
779 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
780 	struct net *net = sock_net(skb->sk);
781 
782 	if (!info->attrs[TIPC_NLA_BEARER])
783 		return -EINVAL;
784 
785 	err = nla_parse_nested(attrs, TIPC_NLA_BEARER_MAX,
786 			       info->attrs[TIPC_NLA_BEARER],
787 			       tipc_nl_bearer_policy);
788 	if (err)
789 		return err;
790 
791 	if (!attrs[TIPC_NLA_BEARER_NAME])
792 		return -EINVAL;
793 
794 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
795 
796 	rtnl_lock();
797 	bearer = tipc_bearer_find(net, name);
798 	if (!bearer) {
799 		rtnl_unlock();
800 		return -EINVAL;
801 	}
802 
803 	bearer_disable(net, bearer);
804 	rtnl_unlock();
805 
806 	return 0;
807 }
808 
809 int tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info)
810 {
811 	int err;
812 	char *bearer;
813 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
814 	struct net *net = sock_net(skb->sk);
815 	struct tipc_net *tn = net_generic(net, tipc_net_id);
816 	u32 domain;
817 	u32 prio;
818 
819 	prio = TIPC_MEDIA_LINK_PRI;
820 	domain = tn->own_addr & TIPC_CLUSTER_MASK;
821 
822 	if (!info->attrs[TIPC_NLA_BEARER])
823 		return -EINVAL;
824 
825 	err = nla_parse_nested(attrs, TIPC_NLA_BEARER_MAX,
826 			       info->attrs[TIPC_NLA_BEARER],
827 			       tipc_nl_bearer_policy);
828 	if (err)
829 		return err;
830 
831 	if (!attrs[TIPC_NLA_BEARER_NAME])
832 		return -EINVAL;
833 
834 	bearer = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
835 
836 	if (attrs[TIPC_NLA_BEARER_DOMAIN])
837 		domain = nla_get_u32(attrs[TIPC_NLA_BEARER_DOMAIN]);
838 
839 	if (attrs[TIPC_NLA_BEARER_PROP]) {
840 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
841 
842 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_BEARER_PROP],
843 					      props);
844 		if (err)
845 			return err;
846 
847 		if (props[TIPC_NLA_PROP_PRIO])
848 			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
849 	}
850 
851 	rtnl_lock();
852 	err = tipc_enable_bearer(net, bearer, domain, prio, attrs);
853 	if (err) {
854 		rtnl_unlock();
855 		return err;
856 	}
857 	rtnl_unlock();
858 
859 	return 0;
860 }
861 
862 int tipc_nl_bearer_set(struct sk_buff *skb, struct genl_info *info)
863 {
864 	int err;
865 	char *name;
866 	struct tipc_bearer *b;
867 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
868 	struct net *net = sock_net(skb->sk);
869 
870 	if (!info->attrs[TIPC_NLA_BEARER])
871 		return -EINVAL;
872 
873 	err = nla_parse_nested(attrs, TIPC_NLA_BEARER_MAX,
874 			       info->attrs[TIPC_NLA_BEARER],
875 			       tipc_nl_bearer_policy);
876 	if (err)
877 		return err;
878 
879 	if (!attrs[TIPC_NLA_BEARER_NAME])
880 		return -EINVAL;
881 	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);
882 
883 	rtnl_lock();
884 	b = tipc_bearer_find(net, name);
885 	if (!b) {
886 		rtnl_unlock();
887 		return -EINVAL;
888 	}
889 
890 	if (attrs[TIPC_NLA_BEARER_PROP]) {
891 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
892 
893 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_BEARER_PROP],
894 					      props);
895 		if (err) {
896 			rtnl_unlock();
897 			return err;
898 		}
899 
900 		if (props[TIPC_NLA_PROP_TOL])
901 			b->tolerance = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
902 		if (props[TIPC_NLA_PROP_PRIO])
903 			b->priority = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
904 		if (props[TIPC_NLA_PROP_WIN])
905 			b->window = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
906 	}
907 	rtnl_unlock();
908 
909 	return 0;
910 }
911 
912 static int __tipc_nl_add_media(struct tipc_nl_msg *msg,
913 			       struct tipc_media *media, int nlflags)
914 {
915 	void *hdr;
916 	struct nlattr *attrs;
917 	struct nlattr *prop;
918 
919 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
920 			  nlflags, TIPC_NL_MEDIA_GET);
921 	if (!hdr)
922 		return -EMSGSIZE;
923 
924 	attrs = nla_nest_start(msg->skb, TIPC_NLA_MEDIA);
925 	if (!attrs)
926 		goto msg_full;
927 
928 	if (nla_put_string(msg->skb, TIPC_NLA_MEDIA_NAME, media->name))
929 		goto attr_msg_full;
930 
931 	prop = nla_nest_start(msg->skb, TIPC_NLA_MEDIA_PROP);
932 	if (!prop)
933 		goto prop_msg_full;
934 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, media->priority))
935 		goto prop_msg_full;
936 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, media->tolerance))
937 		goto prop_msg_full;
938 	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, media->window))
939 		goto prop_msg_full;
940 
941 	nla_nest_end(msg->skb, prop);
942 	nla_nest_end(msg->skb, attrs);
943 	genlmsg_end(msg->skb, hdr);
944 
945 	return 0;
946 
947 prop_msg_full:
948 	nla_nest_cancel(msg->skb, prop);
949 attr_msg_full:
950 	nla_nest_cancel(msg->skb, attrs);
951 msg_full:
952 	genlmsg_cancel(msg->skb, hdr);
953 
954 	return -EMSGSIZE;
955 }
956 
957 int tipc_nl_media_dump(struct sk_buff *skb, struct netlink_callback *cb)
958 {
959 	int err;
960 	int i = cb->args[0];
961 	struct tipc_nl_msg msg;
962 
963 	if (i == MAX_MEDIA)
964 		return 0;
965 
966 	msg.skb = skb;
967 	msg.portid = NETLINK_CB(cb->skb).portid;
968 	msg.seq = cb->nlh->nlmsg_seq;
969 
970 	rtnl_lock();
971 	for (; media_info_array[i] != NULL; i++) {
972 		err = __tipc_nl_add_media(&msg, media_info_array[i],
973 					  NLM_F_MULTI);
974 		if (err)
975 			break;
976 	}
977 	rtnl_unlock();
978 
979 	cb->args[0] = i;
980 	return skb->len;
981 }
982 
983 int tipc_nl_media_get(struct sk_buff *skb, struct genl_info *info)
984 {
985 	int err;
986 	char *name;
987 	struct tipc_nl_msg msg;
988 	struct tipc_media *media;
989 	struct sk_buff *rep;
990 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
991 
992 	if (!info->attrs[TIPC_NLA_MEDIA])
993 		return -EINVAL;
994 
995 	err = nla_parse_nested(attrs, TIPC_NLA_MEDIA_MAX,
996 			       info->attrs[TIPC_NLA_MEDIA],
997 			       tipc_nl_media_policy);
998 	if (err)
999 		return err;
1000 
1001 	if (!attrs[TIPC_NLA_MEDIA_NAME])
1002 		return -EINVAL;
1003 	name = nla_data(attrs[TIPC_NLA_MEDIA_NAME]);
1004 
1005 	rep = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
1006 	if (!rep)
1007 		return -ENOMEM;
1008 
1009 	msg.skb = rep;
1010 	msg.portid = info->snd_portid;
1011 	msg.seq = info->snd_seq;
1012 
1013 	rtnl_lock();
1014 	media = tipc_media_find(name);
1015 	if (!media) {
1016 		err = -EINVAL;
1017 		goto err_out;
1018 	}
1019 
1020 	err = __tipc_nl_add_media(&msg, media, 0);
1021 	if (err)
1022 		goto err_out;
1023 	rtnl_unlock();
1024 
1025 	return genlmsg_reply(rep, info);
1026 err_out:
1027 	rtnl_unlock();
1028 	nlmsg_free(rep);
1029 
1030 	return err;
1031 }
1032 
1033 int tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info)
1034 {
1035 	int err;
1036 	char *name;
1037 	struct tipc_media *m;
1038 	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
1039 
1040 	if (!info->attrs[TIPC_NLA_MEDIA])
1041 		return -EINVAL;
1042 
1043 	err = nla_parse_nested(attrs, TIPC_NLA_MEDIA_MAX,
1044 			       info->attrs[TIPC_NLA_MEDIA],
1045 			       tipc_nl_media_policy);
1046 
1047 	if (!attrs[TIPC_NLA_MEDIA_NAME])
1048 		return -EINVAL;
1049 	name = nla_data(attrs[TIPC_NLA_MEDIA_NAME]);
1050 
1051 	rtnl_lock();
1052 	m = tipc_media_find(name);
1053 	if (!m) {
1054 		rtnl_unlock();
1055 		return -EINVAL;
1056 	}
1057 
1058 	if (attrs[TIPC_NLA_MEDIA_PROP]) {
1059 		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
1060 
1061 		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_MEDIA_PROP],
1062 					      props);
1063 		if (err) {
1064 			rtnl_unlock();
1065 			return err;
1066 		}
1067 
1068 		if (props[TIPC_NLA_PROP_TOL])
1069 			m->tolerance = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1070 		if (props[TIPC_NLA_PROP_PRIO])
1071 			m->priority = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1072 		if (props[TIPC_NLA_PROP_WIN])
1073 			m->window = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1074 	}
1075 	rtnl_unlock();
1076 
1077 	return 0;
1078 }
1079