1 /* Copyright (C) 2007-2014 B.A.T.M.A.N. contributors:
2  *
3  * Marek Lindner, Simon Wunderlich
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of version 2 of the GNU General Public
7  * License as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, see <http://www.gnu.org/licenses/>.
16  */
17 
18 #include "main.h"
19 #include "distributed-arp-table.h"
20 #include "hard-interface.h"
21 #include "soft-interface.h"
22 #include "send.h"
23 #include "translation-table.h"
24 #include "routing.h"
25 #include "sysfs.h"
26 #include "debugfs.h"
27 #include "originator.h"
28 #include "hash.h"
29 #include "bridge_loop_avoidance.h"
30 #include "gateway_client.h"
31 
32 #include <linux/if_arp.h>
33 #include <linux/if_ether.h>
34 
35 void batadv_hardif_free_rcu(struct rcu_head *rcu)
36 {
37 	struct batadv_hard_iface *hard_iface;
38 
39 	hard_iface = container_of(rcu, struct batadv_hard_iface, rcu);
40 	dev_put(hard_iface->net_dev);
41 	kfree(hard_iface);
42 }
43 
44 struct batadv_hard_iface *
45 batadv_hardif_get_by_netdev(const struct net_device *net_dev)
46 {
47 	struct batadv_hard_iface *hard_iface;
48 
49 	rcu_read_lock();
50 	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
51 		if (hard_iface->net_dev == net_dev &&
52 		    atomic_inc_not_zero(&hard_iface->refcount))
53 			goto out;
54 	}
55 
56 	hard_iface = NULL;
57 
58 out:
59 	rcu_read_unlock();
60 	return hard_iface;
61 }
62 
63 /**
64  * batadv_is_on_batman_iface - check if a device is a batman iface descendant
65  * @net_dev: the device to check
66  *
67  * If the user creates any virtual device on top of a batman-adv interface, it
68  * is important to prevent this new interface to be used to create a new mesh
69  * network (this behaviour would lead to a batman-over-batman configuration).
70  * This function recursively checks all the fathers of the device passed as
71  * argument looking for a batman-adv soft interface.
72  *
73  * Returns true if the device is descendant of a batman-adv mesh interface (or
74  * if it is a batman-adv interface itself), false otherwise
75  */
76 static bool batadv_is_on_batman_iface(const struct net_device *net_dev)
77 {
78 	struct net_device *parent_dev;
79 	bool ret;
80 
81 	/* check if this is a batman-adv mesh interface */
82 	if (batadv_softif_is_valid(net_dev))
83 		return true;
84 
85 	/* no more parents..stop recursion */
86 	if (net_dev->iflink == net_dev->ifindex)
87 		return false;
88 
89 	/* recurse over the parent device */
90 	parent_dev = __dev_get_by_index(&init_net, net_dev->iflink);
91 	/* if we got a NULL parent_dev there is something broken.. */
92 	if (WARN(!parent_dev, "Cannot find parent device"))
93 		return false;
94 
95 	ret = batadv_is_on_batman_iface(parent_dev);
96 
97 	return ret;
98 }
99 
100 static int batadv_is_valid_iface(const struct net_device *net_dev)
101 {
102 	if (net_dev->flags & IFF_LOOPBACK)
103 		return 0;
104 
105 	if (net_dev->type != ARPHRD_ETHER)
106 		return 0;
107 
108 	if (net_dev->addr_len != ETH_ALEN)
109 		return 0;
110 
111 	/* no batman over batman */
112 	if (batadv_is_on_batman_iface(net_dev))
113 		return 0;
114 
115 	return 1;
116 }
117 
118 /**
119  * batadv_is_wifi_netdev - check if the given net_device struct is a wifi
120  *  interface
121  * @net_device: the device to check
122  *
123  * Returns true if the net device is a 802.11 wireless device, false otherwise.
124  */
125 bool batadv_is_wifi_netdev(struct net_device *net_device)
126 {
127 	if (!net_device)
128 		return false;
129 
130 #ifdef CONFIG_WIRELESS_EXT
131 	/* pre-cfg80211 drivers have to implement WEXT, so it is possible to
132 	 * check for wireless_handlers != NULL
133 	 */
134 	if (net_device->wireless_handlers)
135 		return true;
136 #endif
137 
138 	/* cfg80211 drivers have to set ieee80211_ptr */
139 	if (net_device->ieee80211_ptr)
140 		return true;
141 
142 	return false;
143 }
144 
145 static struct batadv_hard_iface *
146 batadv_hardif_get_active(const struct net_device *soft_iface)
147 {
148 	struct batadv_hard_iface *hard_iface;
149 
150 	rcu_read_lock();
151 	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
152 		if (hard_iface->soft_iface != soft_iface)
153 			continue;
154 
155 		if (hard_iface->if_status == BATADV_IF_ACTIVE &&
156 		    atomic_inc_not_zero(&hard_iface->refcount))
157 			goto out;
158 	}
159 
160 	hard_iface = NULL;
161 
162 out:
163 	rcu_read_unlock();
164 	return hard_iface;
165 }
166 
167 static void batadv_primary_if_update_addr(struct batadv_priv *bat_priv,
168 					  struct batadv_hard_iface *oldif)
169 {
170 	struct batadv_hard_iface *primary_if;
171 
172 	primary_if = batadv_primary_if_get_selected(bat_priv);
173 	if (!primary_if)
174 		goto out;
175 
176 	batadv_dat_init_own_addr(bat_priv, primary_if);
177 	batadv_bla_update_orig_address(bat_priv, primary_if, oldif);
178 out:
179 	if (primary_if)
180 		batadv_hardif_free_ref(primary_if);
181 }
182 
183 static void batadv_primary_if_select(struct batadv_priv *bat_priv,
184 				     struct batadv_hard_iface *new_hard_iface)
185 {
186 	struct batadv_hard_iface *curr_hard_iface;
187 
188 	ASSERT_RTNL();
189 
190 	if (new_hard_iface && !atomic_inc_not_zero(&new_hard_iface->refcount))
191 		new_hard_iface = NULL;
192 
193 	curr_hard_iface = rcu_dereference_protected(bat_priv->primary_if, 1);
194 	rcu_assign_pointer(bat_priv->primary_if, new_hard_iface);
195 
196 	if (!new_hard_iface)
197 		goto out;
198 
199 	bat_priv->bat_algo_ops->bat_primary_iface_set(new_hard_iface);
200 	batadv_primary_if_update_addr(bat_priv, curr_hard_iface);
201 
202 out:
203 	if (curr_hard_iface)
204 		batadv_hardif_free_ref(curr_hard_iface);
205 }
206 
207 static bool
208 batadv_hardif_is_iface_up(const struct batadv_hard_iface *hard_iface)
209 {
210 	if (hard_iface->net_dev->flags & IFF_UP)
211 		return true;
212 
213 	return false;
214 }
215 
216 static void batadv_check_known_mac_addr(const struct net_device *net_dev)
217 {
218 	const struct batadv_hard_iface *hard_iface;
219 
220 	rcu_read_lock();
221 	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
222 		if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
223 		    (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
224 			continue;
225 
226 		if (hard_iface->net_dev == net_dev)
227 			continue;
228 
229 		if (!batadv_compare_eth(hard_iface->net_dev->dev_addr,
230 					net_dev->dev_addr))
231 			continue;
232 
233 		pr_warn("The newly added mac address (%pM) already exists on: %s\n",
234 			net_dev->dev_addr, hard_iface->net_dev->name);
235 		pr_warn("It is strongly recommended to keep mac addresses unique to avoid problems!\n");
236 	}
237 	rcu_read_unlock();
238 }
239 
240 int batadv_hardif_min_mtu(struct net_device *soft_iface)
241 {
242 	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
243 	const struct batadv_hard_iface *hard_iface;
244 	int min_mtu = INT_MAX;
245 
246 	rcu_read_lock();
247 	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
248 		if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
249 		    (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
250 			continue;
251 
252 		if (hard_iface->soft_iface != soft_iface)
253 			continue;
254 
255 		min_mtu = min_t(int, hard_iface->net_dev->mtu, min_mtu);
256 	}
257 	rcu_read_unlock();
258 
259 	if (atomic_read(&bat_priv->fragmentation) == 0)
260 		goto out;
261 
262 	/* with fragmentation enabled the maximum size of internally generated
263 	 * packets such as translation table exchanges or tvlv containers, etc
264 	 * has to be calculated
265 	 */
266 	min_mtu = min_t(int, min_mtu, BATADV_FRAG_MAX_FRAG_SIZE);
267 	min_mtu -= sizeof(struct batadv_frag_packet);
268 	min_mtu *= BATADV_FRAG_MAX_FRAGMENTS;
269 
270 out:
271 	/* report to the other components the maximum amount of bytes that
272 	 * batman-adv can send over the wire (without considering the payload
273 	 * overhead). For example, this value is used by TT to compute the
274 	 * maximum local table table size
275 	 */
276 	atomic_set(&bat_priv->packet_size_max, min_mtu);
277 
278 	/* the real soft-interface MTU is computed by removing the payload
279 	 * overhead from the maximum amount of bytes that was just computed.
280 	 *
281 	 * However batman-adv does not support MTUs bigger than ETH_DATA_LEN
282 	 */
283 	return min_t(int, min_mtu - batadv_max_header_len(), ETH_DATA_LEN);
284 }
285 
286 /* adjusts the MTU if a new interface with a smaller MTU appeared. */
287 void batadv_update_min_mtu(struct net_device *soft_iface)
288 {
289 	soft_iface->mtu = batadv_hardif_min_mtu(soft_iface);
290 
291 	/* Check if the local translate table should be cleaned up to match a
292 	 * new (and smaller) MTU.
293 	 */
294 	batadv_tt_local_resize_to_mtu(soft_iface);
295 }
296 
297 static void
298 batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface)
299 {
300 	struct batadv_priv *bat_priv;
301 	struct batadv_hard_iface *primary_if = NULL;
302 
303 	if (hard_iface->if_status != BATADV_IF_INACTIVE)
304 		goto out;
305 
306 	bat_priv = netdev_priv(hard_iface->soft_iface);
307 
308 	bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
309 	hard_iface->if_status = BATADV_IF_TO_BE_ACTIVATED;
310 
311 	/* the first active interface becomes our primary interface or
312 	 * the next active interface after the old primary interface was removed
313 	 */
314 	primary_if = batadv_primary_if_get_selected(bat_priv);
315 	if (!primary_if)
316 		batadv_primary_if_select(bat_priv, hard_iface);
317 
318 	batadv_info(hard_iface->soft_iface, "Interface activated: %s\n",
319 		    hard_iface->net_dev->name);
320 
321 	batadv_update_min_mtu(hard_iface->soft_iface);
322 
323 out:
324 	if (primary_if)
325 		batadv_hardif_free_ref(primary_if);
326 }
327 
328 static void
329 batadv_hardif_deactivate_interface(struct batadv_hard_iface *hard_iface)
330 {
331 	if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
332 	    (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
333 		return;
334 
335 	hard_iface->if_status = BATADV_IF_INACTIVE;
336 
337 	batadv_info(hard_iface->soft_iface, "Interface deactivated: %s\n",
338 		    hard_iface->net_dev->name);
339 
340 	batadv_update_min_mtu(hard_iface->soft_iface);
341 }
342 
343 /**
344  * batadv_master_del_slave - remove hard_iface from the current master interface
345  * @slave: the interface enslaved in another master
346  * @master: the master from which slave has to be removed
347  *
348  * Invoke ndo_del_slave on master passing slave as argument. In this way slave
349  * is free'd and master can correctly change its internal state.
350  * Return 0 on success, a negative value representing the error otherwise
351  */
352 static int batadv_master_del_slave(struct batadv_hard_iface *slave,
353 				   struct net_device *master)
354 {
355 	int ret;
356 
357 	if (!master)
358 		return 0;
359 
360 	ret = -EBUSY;
361 	if (master->netdev_ops->ndo_del_slave)
362 		ret = master->netdev_ops->ndo_del_slave(master, slave->net_dev);
363 
364 	return ret;
365 }
366 
367 int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
368 				   const char *iface_name)
369 {
370 	struct batadv_priv *bat_priv;
371 	struct net_device *soft_iface, *master;
372 	__be16 ethertype = htons(ETH_P_BATMAN);
373 	int max_header_len = batadv_max_header_len();
374 	int ret;
375 
376 	if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
377 		goto out;
378 
379 	if (!atomic_inc_not_zero(&hard_iface->refcount))
380 		goto out;
381 
382 	soft_iface = dev_get_by_name(&init_net, iface_name);
383 
384 	if (!soft_iface) {
385 		soft_iface = batadv_softif_create(iface_name);
386 
387 		if (!soft_iface) {
388 			ret = -ENOMEM;
389 			goto err;
390 		}
391 
392 		/* dev_get_by_name() increases the reference counter for us */
393 		dev_hold(soft_iface);
394 	}
395 
396 	if (!batadv_softif_is_valid(soft_iface)) {
397 		pr_err("Can't create batman mesh interface %s: already exists as regular interface\n",
398 		       soft_iface->name);
399 		ret = -EINVAL;
400 		goto err_dev;
401 	}
402 
403 	/* check if the interface is enslaved in another virtual one and
404 	 * in that case unlink it first
405 	 */
406 	master = netdev_master_upper_dev_get(hard_iface->net_dev);
407 	ret = batadv_master_del_slave(hard_iface, master);
408 	if (ret)
409 		goto err_dev;
410 
411 	hard_iface->soft_iface = soft_iface;
412 	bat_priv = netdev_priv(hard_iface->soft_iface);
413 
414 	ret = netdev_master_upper_dev_link(hard_iface->net_dev, soft_iface);
415 	if (ret)
416 		goto err_dev;
417 
418 	ret = bat_priv->bat_algo_ops->bat_iface_enable(hard_iface);
419 	if (ret < 0)
420 		goto err_upper;
421 
422 	hard_iface->if_num = bat_priv->num_ifaces;
423 	bat_priv->num_ifaces++;
424 	hard_iface->if_status = BATADV_IF_INACTIVE;
425 	ret = batadv_orig_hash_add_if(hard_iface, bat_priv->num_ifaces);
426 	if (ret < 0) {
427 		bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
428 		bat_priv->num_ifaces--;
429 		hard_iface->if_status = BATADV_IF_NOT_IN_USE;
430 		goto err_upper;
431 	}
432 
433 	hard_iface->batman_adv_ptype.type = ethertype;
434 	hard_iface->batman_adv_ptype.func = batadv_batman_skb_recv;
435 	hard_iface->batman_adv_ptype.dev = hard_iface->net_dev;
436 	dev_add_pack(&hard_iface->batman_adv_ptype);
437 
438 	batadv_info(hard_iface->soft_iface, "Adding interface: %s\n",
439 		    hard_iface->net_dev->name);
440 
441 	if (atomic_read(&bat_priv->fragmentation) &&
442 	    hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
443 		batadv_info(hard_iface->soft_iface,
444 			    "The MTU of interface %s is too small (%i) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to %i would solve the problem.\n",
445 			    hard_iface->net_dev->name, hard_iface->net_dev->mtu,
446 			    ETH_DATA_LEN + max_header_len);
447 
448 	if (!atomic_read(&bat_priv->fragmentation) &&
449 	    hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
450 		batadv_info(hard_iface->soft_iface,
451 			    "The MTU of interface %s is too small (%i) to handle the transport of batman-adv packets. If you experience problems getting traffic through try increasing the MTU to %i.\n",
452 			    hard_iface->net_dev->name, hard_iface->net_dev->mtu,
453 			    ETH_DATA_LEN + max_header_len);
454 
455 	if (batadv_hardif_is_iface_up(hard_iface))
456 		batadv_hardif_activate_interface(hard_iface);
457 	else
458 		batadv_err(hard_iface->soft_iface,
459 			   "Not using interface %s (retrying later): interface not active\n",
460 			   hard_iface->net_dev->name);
461 
462 	/* begin scheduling originator messages on that interface */
463 	batadv_schedule_bat_ogm(hard_iface);
464 
465 out:
466 	return 0;
467 
468 err_upper:
469 	netdev_upper_dev_unlink(hard_iface->net_dev, soft_iface);
470 err_dev:
471 	hard_iface->soft_iface = NULL;
472 	dev_put(soft_iface);
473 err:
474 	batadv_hardif_free_ref(hard_iface);
475 	return ret;
476 }
477 
478 void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
479 				     enum batadv_hard_if_cleanup autodel)
480 {
481 	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
482 	struct batadv_hard_iface *primary_if = NULL;
483 
484 	if (hard_iface->if_status == BATADV_IF_ACTIVE)
485 		batadv_hardif_deactivate_interface(hard_iface);
486 
487 	if (hard_iface->if_status != BATADV_IF_INACTIVE)
488 		goto out;
489 
490 	batadv_info(hard_iface->soft_iface, "Removing interface: %s\n",
491 		    hard_iface->net_dev->name);
492 	dev_remove_pack(&hard_iface->batman_adv_ptype);
493 
494 	bat_priv->num_ifaces--;
495 	batadv_orig_hash_del_if(hard_iface, bat_priv->num_ifaces);
496 
497 	primary_if = batadv_primary_if_get_selected(bat_priv);
498 	if (hard_iface == primary_if) {
499 		struct batadv_hard_iface *new_if;
500 
501 		new_if = batadv_hardif_get_active(hard_iface->soft_iface);
502 		batadv_primary_if_select(bat_priv, new_if);
503 
504 		if (new_if)
505 			batadv_hardif_free_ref(new_if);
506 	}
507 
508 	bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
509 	hard_iface->if_status = BATADV_IF_NOT_IN_USE;
510 
511 	/* delete all references to this hard_iface */
512 	batadv_purge_orig_ref(bat_priv);
513 	batadv_purge_outstanding_packets(bat_priv, hard_iface);
514 	dev_put(hard_iface->soft_iface);
515 
516 	/* nobody uses this interface anymore */
517 	if (!bat_priv->num_ifaces) {
518 		batadv_gw_check_client_stop(bat_priv);
519 
520 		if (autodel == BATADV_IF_CLEANUP_AUTO)
521 			batadv_softif_destroy_sysfs(hard_iface->soft_iface);
522 	}
523 
524 	netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);
525 	hard_iface->soft_iface = NULL;
526 	batadv_hardif_free_ref(hard_iface);
527 
528 out:
529 	if (primary_if)
530 		batadv_hardif_free_ref(primary_if);
531 }
532 
533 /**
534  * batadv_hardif_remove_interface_finish - cleans up the remains of a hardif
535  * @work: work queue item
536  *
537  * Free the parts of the hard interface which can not be removed under
538  * rtnl lock (to prevent deadlock situations).
539  */
540 static void batadv_hardif_remove_interface_finish(struct work_struct *work)
541 {
542 	struct batadv_hard_iface *hard_iface;
543 
544 	hard_iface = container_of(work, struct batadv_hard_iface,
545 				  cleanup_work);
546 
547 	batadv_debugfs_del_hardif(hard_iface);
548 	batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
549 	batadv_hardif_free_ref(hard_iface);
550 }
551 
552 static struct batadv_hard_iface *
553 batadv_hardif_add_interface(struct net_device *net_dev)
554 {
555 	struct batadv_hard_iface *hard_iface;
556 	int ret;
557 
558 	ASSERT_RTNL();
559 
560 	ret = batadv_is_valid_iface(net_dev);
561 	if (ret != 1)
562 		goto out;
563 
564 	dev_hold(net_dev);
565 
566 	hard_iface = kzalloc(sizeof(*hard_iface), GFP_ATOMIC);
567 	if (!hard_iface)
568 		goto release_dev;
569 
570 	ret = batadv_sysfs_add_hardif(&hard_iface->hardif_obj, net_dev);
571 	if (ret)
572 		goto free_if;
573 
574 	hard_iface->if_num = -1;
575 	hard_iface->net_dev = net_dev;
576 	hard_iface->soft_iface = NULL;
577 	hard_iface->if_status = BATADV_IF_NOT_IN_USE;
578 
579 	ret = batadv_debugfs_add_hardif(hard_iface);
580 	if (ret)
581 		goto free_sysfs;
582 
583 	INIT_LIST_HEAD(&hard_iface->list);
584 	INIT_WORK(&hard_iface->cleanup_work,
585 		  batadv_hardif_remove_interface_finish);
586 
587 	hard_iface->num_bcasts = BATADV_NUM_BCASTS_DEFAULT;
588 	if (batadv_is_wifi_netdev(net_dev))
589 		hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS;
590 
591 	/* extra reference for return */
592 	atomic_set(&hard_iface->refcount, 2);
593 
594 	batadv_check_known_mac_addr(hard_iface->net_dev);
595 	list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);
596 
597 	return hard_iface;
598 
599 free_sysfs:
600 	batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
601 free_if:
602 	kfree(hard_iface);
603 release_dev:
604 	dev_put(net_dev);
605 out:
606 	return NULL;
607 }
608 
609 static void batadv_hardif_remove_interface(struct batadv_hard_iface *hard_iface)
610 {
611 	ASSERT_RTNL();
612 
613 	/* first deactivate interface */
614 	if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
615 		batadv_hardif_disable_interface(hard_iface,
616 						BATADV_IF_CLEANUP_AUTO);
617 
618 	if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
619 		return;
620 
621 	hard_iface->if_status = BATADV_IF_TO_BE_REMOVED;
622 	queue_work(batadv_event_workqueue, &hard_iface->cleanup_work);
623 }
624 
625 void batadv_hardif_remove_interfaces(void)
626 {
627 	struct batadv_hard_iface *hard_iface, *hard_iface_tmp;
628 
629 	rtnl_lock();
630 	list_for_each_entry_safe(hard_iface, hard_iface_tmp,
631 				 &batadv_hardif_list, list) {
632 		list_del_rcu(&hard_iface->list);
633 		batadv_hardif_remove_interface(hard_iface);
634 	}
635 	rtnl_unlock();
636 }
637 
638 static int batadv_hard_if_event(struct notifier_block *this,
639 				unsigned long event, void *ptr)
640 {
641 	struct net_device *net_dev = netdev_notifier_info_to_dev(ptr);
642 	struct batadv_hard_iface *hard_iface;
643 	struct batadv_hard_iface *primary_if = NULL;
644 	struct batadv_priv *bat_priv;
645 
646 	if (batadv_softif_is_valid(net_dev) && event == NETDEV_REGISTER) {
647 		batadv_sysfs_add_meshif(net_dev);
648 		bat_priv = netdev_priv(net_dev);
649 		batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS);
650 		return NOTIFY_DONE;
651 	}
652 
653 	hard_iface = batadv_hardif_get_by_netdev(net_dev);
654 	if (!hard_iface && event == NETDEV_REGISTER)
655 		hard_iface = batadv_hardif_add_interface(net_dev);
656 
657 	if (!hard_iface)
658 		goto out;
659 
660 	switch (event) {
661 	case NETDEV_UP:
662 		batadv_hardif_activate_interface(hard_iface);
663 		break;
664 	case NETDEV_GOING_DOWN:
665 	case NETDEV_DOWN:
666 		batadv_hardif_deactivate_interface(hard_iface);
667 		break;
668 	case NETDEV_UNREGISTER:
669 		list_del_rcu(&hard_iface->list);
670 
671 		batadv_hardif_remove_interface(hard_iface);
672 		break;
673 	case NETDEV_CHANGEMTU:
674 		if (hard_iface->soft_iface)
675 			batadv_update_min_mtu(hard_iface->soft_iface);
676 		break;
677 	case NETDEV_CHANGEADDR:
678 		if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
679 			goto hardif_put;
680 
681 		batadv_check_known_mac_addr(hard_iface->net_dev);
682 
683 		bat_priv = netdev_priv(hard_iface->soft_iface);
684 		bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
685 
686 		primary_if = batadv_primary_if_get_selected(bat_priv);
687 		if (!primary_if)
688 			goto hardif_put;
689 
690 		if (hard_iface == primary_if)
691 			batadv_primary_if_update_addr(bat_priv, NULL);
692 		break;
693 	default:
694 		break;
695 	}
696 
697 hardif_put:
698 	batadv_hardif_free_ref(hard_iface);
699 out:
700 	if (primary_if)
701 		batadv_hardif_free_ref(primary_if);
702 	return NOTIFY_DONE;
703 }
704 
705 struct notifier_block batadv_hard_if_notifier = {
706 	.notifier_call = batadv_hard_if_event,
707 };
708