xref: /linux/net/batman-adv/tvlv.c (revision fd639726bf15fca8ee1a00dce8e0096d0ad9bd18)
1 /* Copyright (C) 2007-2017  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 
20 #include <linux/byteorder/generic.h>
21 #include <linux/etherdevice.h>
22 #include <linux/fs.h>
23 #include <linux/if_ether.h>
24 #include <linux/kernel.h>
25 #include <linux/kref.h>
26 #include <linux/list.h>
27 #include <linux/lockdep.h>
28 #include <linux/netdevice.h>
29 #include <linux/pkt_sched.h>
30 #include <linux/rculist.h>
31 #include <linux/rcupdate.h>
32 #include <linux/skbuff.h>
33 #include <linux/slab.h>
34 #include <linux/spinlock.h>
35 #include <linux/stddef.h>
36 #include <linux/string.h>
37 #include <linux/types.h>
38 
39 #include "originator.h"
40 #include "packet.h"
41 #include "send.h"
42 #include "tvlv.h"
43 
44 /**
45  * batadv_tvlv_handler_release - release tvlv handler from lists and queue for
46  *  free after rcu grace period
47  * @ref: kref pointer of the tvlv
48  */
49 static void batadv_tvlv_handler_release(struct kref *ref)
50 {
51 	struct batadv_tvlv_handler *tvlv_handler;
52 
53 	tvlv_handler = container_of(ref, struct batadv_tvlv_handler, refcount);
54 	kfree_rcu(tvlv_handler, rcu);
55 }
56 
57 /**
58  * batadv_tvlv_handler_put - decrement the tvlv container refcounter and
59  *  possibly release it
60  * @tvlv_handler: the tvlv handler to free
61  */
62 static void batadv_tvlv_handler_put(struct batadv_tvlv_handler *tvlv_handler)
63 {
64 	kref_put(&tvlv_handler->refcount, batadv_tvlv_handler_release);
65 }
66 
67 /**
68  * batadv_tvlv_handler_get - retrieve tvlv handler from the tvlv handler list
69  *  based on the provided type and version (both need to match)
70  * @bat_priv: the bat priv with all the soft interface information
71  * @type: tvlv handler type to look for
72  * @version: tvlv handler version to look for
73  *
74  * Return: tvlv handler if found or NULL otherwise.
75  */
76 static struct batadv_tvlv_handler *
77 batadv_tvlv_handler_get(struct batadv_priv *bat_priv, u8 type, u8 version)
78 {
79 	struct batadv_tvlv_handler *tvlv_handler_tmp, *tvlv_handler = NULL;
80 
81 	rcu_read_lock();
82 	hlist_for_each_entry_rcu(tvlv_handler_tmp,
83 				 &bat_priv->tvlv.handler_list, list) {
84 		if (tvlv_handler_tmp->type != type)
85 			continue;
86 
87 		if (tvlv_handler_tmp->version != version)
88 			continue;
89 
90 		if (!kref_get_unless_zero(&tvlv_handler_tmp->refcount))
91 			continue;
92 
93 		tvlv_handler = tvlv_handler_tmp;
94 		break;
95 	}
96 	rcu_read_unlock();
97 
98 	return tvlv_handler;
99 }
100 
101 /**
102  * batadv_tvlv_container_release - release tvlv from lists and free
103  * @ref: kref pointer of the tvlv
104  */
105 static void batadv_tvlv_container_release(struct kref *ref)
106 {
107 	struct batadv_tvlv_container *tvlv;
108 
109 	tvlv = container_of(ref, struct batadv_tvlv_container, refcount);
110 	kfree(tvlv);
111 }
112 
113 /**
114  * batadv_tvlv_container_put - decrement the tvlv container refcounter and
115  *  possibly release it
116  * @tvlv: the tvlv container to free
117  */
118 static void batadv_tvlv_container_put(struct batadv_tvlv_container *tvlv)
119 {
120 	kref_put(&tvlv->refcount, batadv_tvlv_container_release);
121 }
122 
123 /**
124  * batadv_tvlv_container_get - retrieve tvlv container from the tvlv container
125  *  list based on the provided type and version (both need to match)
126  * @bat_priv: the bat priv with all the soft interface information
127  * @type: tvlv container type to look for
128  * @version: tvlv container version to look for
129  *
130  * Has to be called with the appropriate locks being acquired
131  * (tvlv.container_list_lock).
132  *
133  * Return: tvlv container if found or NULL otherwise.
134  */
135 static struct batadv_tvlv_container *
136 batadv_tvlv_container_get(struct batadv_priv *bat_priv, u8 type, u8 version)
137 {
138 	struct batadv_tvlv_container *tvlv_tmp, *tvlv = NULL;
139 
140 	lockdep_assert_held(&bat_priv->tvlv.container_list_lock);
141 
142 	hlist_for_each_entry(tvlv_tmp, &bat_priv->tvlv.container_list, list) {
143 		if (tvlv_tmp->tvlv_hdr.type != type)
144 			continue;
145 
146 		if (tvlv_tmp->tvlv_hdr.version != version)
147 			continue;
148 
149 		kref_get(&tvlv_tmp->refcount);
150 		tvlv = tvlv_tmp;
151 		break;
152 	}
153 
154 	return tvlv;
155 }
156 
157 /**
158  * batadv_tvlv_container_list_size - calculate the size of the tvlv container
159  *  list entries
160  * @bat_priv: the bat priv with all the soft interface information
161  *
162  * Has to be called with the appropriate locks being acquired
163  * (tvlv.container_list_lock).
164  *
165  * Return: size of all currently registered tvlv containers in bytes.
166  */
167 static u16 batadv_tvlv_container_list_size(struct batadv_priv *bat_priv)
168 {
169 	struct batadv_tvlv_container *tvlv;
170 	u16 tvlv_len = 0;
171 
172 	lockdep_assert_held(&bat_priv->tvlv.container_list_lock);
173 
174 	hlist_for_each_entry(tvlv, &bat_priv->tvlv.container_list, list) {
175 		tvlv_len += sizeof(struct batadv_tvlv_hdr);
176 		tvlv_len += ntohs(tvlv->tvlv_hdr.len);
177 	}
178 
179 	return tvlv_len;
180 }
181 
182 /**
183  * batadv_tvlv_container_remove - remove tvlv container from the tvlv container
184  *  list
185  * @bat_priv: the bat priv with all the soft interface information
186  * @tvlv: the to be removed tvlv container
187  *
188  * Has to be called with the appropriate locks being acquired
189  * (tvlv.container_list_lock).
190  */
191 static void batadv_tvlv_container_remove(struct batadv_priv *bat_priv,
192 					 struct batadv_tvlv_container *tvlv)
193 {
194 	lockdep_assert_held(&bat_priv->tvlv.container_list_lock);
195 
196 	if (!tvlv)
197 		return;
198 
199 	hlist_del(&tvlv->list);
200 
201 	/* first call to decrement the counter, second call to free */
202 	batadv_tvlv_container_put(tvlv);
203 	batadv_tvlv_container_put(tvlv);
204 }
205 
206 /**
207  * batadv_tvlv_container_unregister - unregister tvlv container based on the
208  *  provided type and version (both need to match)
209  * @bat_priv: the bat priv with all the soft interface information
210  * @type: tvlv container type to unregister
211  * @version: tvlv container type to unregister
212  */
213 void batadv_tvlv_container_unregister(struct batadv_priv *bat_priv,
214 				      u8 type, u8 version)
215 {
216 	struct batadv_tvlv_container *tvlv;
217 
218 	spin_lock_bh(&bat_priv->tvlv.container_list_lock);
219 	tvlv = batadv_tvlv_container_get(bat_priv, type, version);
220 	batadv_tvlv_container_remove(bat_priv, tvlv);
221 	spin_unlock_bh(&bat_priv->tvlv.container_list_lock);
222 }
223 
224 /**
225  * batadv_tvlv_container_register - register tvlv type, version and content
226  *  to be propagated with each (primary interface) OGM
227  * @bat_priv: the bat priv with all the soft interface information
228  * @type: tvlv container type
229  * @version: tvlv container version
230  * @tvlv_value: tvlv container content
231  * @tvlv_value_len: tvlv container content length
232  *
233  * If a container of the same type and version was already registered the new
234  * content is going to replace the old one.
235  */
236 void batadv_tvlv_container_register(struct batadv_priv *bat_priv,
237 				    u8 type, u8 version,
238 				    void *tvlv_value, u16 tvlv_value_len)
239 {
240 	struct batadv_tvlv_container *tvlv_old, *tvlv_new;
241 
242 	if (!tvlv_value)
243 		tvlv_value_len = 0;
244 
245 	tvlv_new = kzalloc(sizeof(*tvlv_new) + tvlv_value_len, GFP_ATOMIC);
246 	if (!tvlv_new)
247 		return;
248 
249 	tvlv_new->tvlv_hdr.version = version;
250 	tvlv_new->tvlv_hdr.type = type;
251 	tvlv_new->tvlv_hdr.len = htons(tvlv_value_len);
252 
253 	memcpy(tvlv_new + 1, tvlv_value, ntohs(tvlv_new->tvlv_hdr.len));
254 	INIT_HLIST_NODE(&tvlv_new->list);
255 	kref_init(&tvlv_new->refcount);
256 
257 	spin_lock_bh(&bat_priv->tvlv.container_list_lock);
258 	tvlv_old = batadv_tvlv_container_get(bat_priv, type, version);
259 	batadv_tvlv_container_remove(bat_priv, tvlv_old);
260 
261 	kref_get(&tvlv_new->refcount);
262 	hlist_add_head(&tvlv_new->list, &bat_priv->tvlv.container_list);
263 	spin_unlock_bh(&bat_priv->tvlv.container_list_lock);
264 
265 	/* don't return reference to new tvlv_container */
266 	batadv_tvlv_container_put(tvlv_new);
267 }
268 
269 /**
270  * batadv_tvlv_realloc_packet_buff - reallocate packet buffer to accommodate
271  *  requested packet size
272  * @packet_buff: packet buffer
273  * @packet_buff_len: packet buffer size
274  * @min_packet_len: requested packet minimum size
275  * @additional_packet_len: requested additional packet size on top of minimum
276  *  size
277  *
278  * Return: true of the packet buffer could be changed to the requested size,
279  * false otherwise.
280  */
281 static bool batadv_tvlv_realloc_packet_buff(unsigned char **packet_buff,
282 					    int *packet_buff_len,
283 					    int min_packet_len,
284 					    int additional_packet_len)
285 {
286 	unsigned char *new_buff;
287 
288 	new_buff = kmalloc(min_packet_len + additional_packet_len, GFP_ATOMIC);
289 
290 	/* keep old buffer if kmalloc should fail */
291 	if (!new_buff)
292 		return false;
293 
294 	memcpy(new_buff, *packet_buff, min_packet_len);
295 	kfree(*packet_buff);
296 	*packet_buff = new_buff;
297 	*packet_buff_len = min_packet_len + additional_packet_len;
298 
299 	return true;
300 }
301 
302 /**
303  * batadv_tvlv_container_ogm_append - append tvlv container content to given
304  *  OGM packet buffer
305  * @bat_priv: the bat priv with all the soft interface information
306  * @packet_buff: ogm packet buffer
307  * @packet_buff_len: ogm packet buffer size including ogm header and tvlv
308  *  content
309  * @packet_min_len: ogm header size to be preserved for the OGM itself
310  *
311  * The ogm packet might be enlarged or shrunk depending on the current size
312  * and the size of the to-be-appended tvlv containers.
313  *
314  * Return: size of all appended tvlv containers in bytes.
315  */
316 u16 batadv_tvlv_container_ogm_append(struct batadv_priv *bat_priv,
317 				     unsigned char **packet_buff,
318 				     int *packet_buff_len, int packet_min_len)
319 {
320 	struct batadv_tvlv_container *tvlv;
321 	struct batadv_tvlv_hdr *tvlv_hdr;
322 	u16 tvlv_value_len;
323 	void *tvlv_value;
324 	bool ret;
325 
326 	spin_lock_bh(&bat_priv->tvlv.container_list_lock);
327 	tvlv_value_len = batadv_tvlv_container_list_size(bat_priv);
328 
329 	ret = batadv_tvlv_realloc_packet_buff(packet_buff, packet_buff_len,
330 					      packet_min_len, tvlv_value_len);
331 
332 	if (!ret)
333 		goto end;
334 
335 	if (!tvlv_value_len)
336 		goto end;
337 
338 	tvlv_value = (*packet_buff) + packet_min_len;
339 
340 	hlist_for_each_entry(tvlv, &bat_priv->tvlv.container_list, list) {
341 		tvlv_hdr = tvlv_value;
342 		tvlv_hdr->type = tvlv->tvlv_hdr.type;
343 		tvlv_hdr->version = tvlv->tvlv_hdr.version;
344 		tvlv_hdr->len = tvlv->tvlv_hdr.len;
345 		tvlv_value = tvlv_hdr + 1;
346 		memcpy(tvlv_value, tvlv + 1, ntohs(tvlv->tvlv_hdr.len));
347 		tvlv_value = (u8 *)tvlv_value + ntohs(tvlv->tvlv_hdr.len);
348 	}
349 
350 end:
351 	spin_unlock_bh(&bat_priv->tvlv.container_list_lock);
352 	return tvlv_value_len;
353 }
354 
355 /**
356  * batadv_tvlv_call_handler - parse the given tvlv buffer to call the
357  *  appropriate handlers
358  * @bat_priv: the bat priv with all the soft interface information
359  * @tvlv_handler: tvlv callback function handling the tvlv content
360  * @ogm_source: flag indicating whether the tvlv is an ogm or a unicast packet
361  * @orig_node: orig node emitting the ogm packet
362  * @src: source mac address of the unicast packet
363  * @dst: destination mac address of the unicast packet
364  * @tvlv_value: tvlv content
365  * @tvlv_value_len: tvlv content length
366  *
367  * Return: success if handler was not found or the return value of the handler
368  * callback.
369  */
370 static int batadv_tvlv_call_handler(struct batadv_priv *bat_priv,
371 				    struct batadv_tvlv_handler *tvlv_handler,
372 				    bool ogm_source,
373 				    struct batadv_orig_node *orig_node,
374 				    u8 *src, u8 *dst,
375 				    void *tvlv_value, u16 tvlv_value_len)
376 {
377 	if (!tvlv_handler)
378 		return NET_RX_SUCCESS;
379 
380 	if (ogm_source) {
381 		if (!tvlv_handler->ogm_handler)
382 			return NET_RX_SUCCESS;
383 
384 		if (!orig_node)
385 			return NET_RX_SUCCESS;
386 
387 		tvlv_handler->ogm_handler(bat_priv, orig_node,
388 					  BATADV_NO_FLAGS,
389 					  tvlv_value, tvlv_value_len);
390 		tvlv_handler->flags |= BATADV_TVLV_HANDLER_OGM_CALLED;
391 	} else {
392 		if (!src)
393 			return NET_RX_SUCCESS;
394 
395 		if (!dst)
396 			return NET_RX_SUCCESS;
397 
398 		if (!tvlv_handler->unicast_handler)
399 			return NET_RX_SUCCESS;
400 
401 		return tvlv_handler->unicast_handler(bat_priv, src,
402 						     dst, tvlv_value,
403 						     tvlv_value_len);
404 	}
405 
406 	return NET_RX_SUCCESS;
407 }
408 
409 /**
410  * batadv_tvlv_containers_process - parse the given tvlv buffer to call the
411  *  appropriate handlers
412  * @bat_priv: the bat priv with all the soft interface information
413  * @ogm_source: flag indicating whether the tvlv is an ogm or a unicast packet
414  * @orig_node: orig node emitting the ogm packet
415  * @src: source mac address of the unicast packet
416  * @dst: destination mac address of the unicast packet
417  * @tvlv_value: tvlv content
418  * @tvlv_value_len: tvlv content length
419  *
420  * Return: success when processing an OGM or the return value of all called
421  * handler callbacks.
422  */
423 int batadv_tvlv_containers_process(struct batadv_priv *bat_priv,
424 				   bool ogm_source,
425 				   struct batadv_orig_node *orig_node,
426 				   u8 *src, u8 *dst,
427 				   void *tvlv_value, u16 tvlv_value_len)
428 {
429 	struct batadv_tvlv_handler *tvlv_handler;
430 	struct batadv_tvlv_hdr *tvlv_hdr;
431 	u16 tvlv_value_cont_len;
432 	u8 cifnotfound = BATADV_TVLV_HANDLER_OGM_CIFNOTFND;
433 	int ret = NET_RX_SUCCESS;
434 
435 	while (tvlv_value_len >= sizeof(*tvlv_hdr)) {
436 		tvlv_hdr = tvlv_value;
437 		tvlv_value_cont_len = ntohs(tvlv_hdr->len);
438 		tvlv_value = tvlv_hdr + 1;
439 		tvlv_value_len -= sizeof(*tvlv_hdr);
440 
441 		if (tvlv_value_cont_len > tvlv_value_len)
442 			break;
443 
444 		tvlv_handler = batadv_tvlv_handler_get(bat_priv,
445 						       tvlv_hdr->type,
446 						       tvlv_hdr->version);
447 
448 		ret |= batadv_tvlv_call_handler(bat_priv, tvlv_handler,
449 						ogm_source, orig_node,
450 						src, dst, tvlv_value,
451 						tvlv_value_cont_len);
452 		if (tvlv_handler)
453 			batadv_tvlv_handler_put(tvlv_handler);
454 		tvlv_value = (u8 *)tvlv_value + tvlv_value_cont_len;
455 		tvlv_value_len -= tvlv_value_cont_len;
456 	}
457 
458 	if (!ogm_source)
459 		return ret;
460 
461 	rcu_read_lock();
462 	hlist_for_each_entry_rcu(tvlv_handler,
463 				 &bat_priv->tvlv.handler_list, list) {
464 		if ((tvlv_handler->flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND) &&
465 		    !(tvlv_handler->flags & BATADV_TVLV_HANDLER_OGM_CALLED))
466 			tvlv_handler->ogm_handler(bat_priv, orig_node,
467 						  cifnotfound, NULL, 0);
468 
469 		tvlv_handler->flags &= ~BATADV_TVLV_HANDLER_OGM_CALLED;
470 	}
471 	rcu_read_unlock();
472 
473 	return NET_RX_SUCCESS;
474 }
475 
476 /**
477  * batadv_tvlv_ogm_receive - process an incoming ogm and call the appropriate
478  *  handlers
479  * @bat_priv: the bat priv with all the soft interface information
480  * @batadv_ogm_packet: ogm packet containing the tvlv containers
481  * @orig_node: orig node emitting the ogm packet
482  */
483 void batadv_tvlv_ogm_receive(struct batadv_priv *bat_priv,
484 			     struct batadv_ogm_packet *batadv_ogm_packet,
485 			     struct batadv_orig_node *orig_node)
486 {
487 	void *tvlv_value;
488 	u16 tvlv_value_len;
489 
490 	if (!batadv_ogm_packet)
491 		return;
492 
493 	tvlv_value_len = ntohs(batadv_ogm_packet->tvlv_len);
494 	if (!tvlv_value_len)
495 		return;
496 
497 	tvlv_value = batadv_ogm_packet + 1;
498 
499 	batadv_tvlv_containers_process(bat_priv, true, orig_node, NULL, NULL,
500 				       tvlv_value, tvlv_value_len);
501 }
502 
503 /**
504  * batadv_tvlv_handler_register - register tvlv handler based on the provided
505  *  type and version (both need to match) for ogm tvlv payload and/or unicast
506  *  payload
507  * @bat_priv: the bat priv with all the soft interface information
508  * @optr: ogm tvlv handler callback function. This function receives the orig
509  *  node, flags and the tvlv content as argument to process.
510  * @uptr: unicast tvlv handler callback function. This function receives the
511  *  source & destination of the unicast packet as well as the tvlv content
512  *  to process.
513  * @type: tvlv handler type to be registered
514  * @version: tvlv handler version to be registered
515  * @flags: flags to enable or disable TVLV API behavior
516  */
517 void batadv_tvlv_handler_register(struct batadv_priv *bat_priv,
518 				  void (*optr)(struct batadv_priv *bat_priv,
519 					       struct batadv_orig_node *orig,
520 					       u8 flags,
521 					       void *tvlv_value,
522 					       u16 tvlv_value_len),
523 				  int (*uptr)(struct batadv_priv *bat_priv,
524 					      u8 *src, u8 *dst,
525 					      void *tvlv_value,
526 					      u16 tvlv_value_len),
527 				  u8 type, u8 version, u8 flags)
528 {
529 	struct batadv_tvlv_handler *tvlv_handler;
530 
531 	tvlv_handler = batadv_tvlv_handler_get(bat_priv, type, version);
532 	if (tvlv_handler) {
533 		batadv_tvlv_handler_put(tvlv_handler);
534 		return;
535 	}
536 
537 	tvlv_handler = kzalloc(sizeof(*tvlv_handler), GFP_ATOMIC);
538 	if (!tvlv_handler)
539 		return;
540 
541 	tvlv_handler->ogm_handler = optr;
542 	tvlv_handler->unicast_handler = uptr;
543 	tvlv_handler->type = type;
544 	tvlv_handler->version = version;
545 	tvlv_handler->flags = flags;
546 	kref_init(&tvlv_handler->refcount);
547 	INIT_HLIST_NODE(&tvlv_handler->list);
548 
549 	spin_lock_bh(&bat_priv->tvlv.handler_list_lock);
550 	kref_get(&tvlv_handler->refcount);
551 	hlist_add_head_rcu(&tvlv_handler->list, &bat_priv->tvlv.handler_list);
552 	spin_unlock_bh(&bat_priv->tvlv.handler_list_lock);
553 
554 	/* don't return reference to new tvlv_handler */
555 	batadv_tvlv_handler_put(tvlv_handler);
556 }
557 
558 /**
559  * batadv_tvlv_handler_unregister - unregister tvlv handler based on the
560  *  provided type and version (both need to match)
561  * @bat_priv: the bat priv with all the soft interface information
562  * @type: tvlv handler type to be unregistered
563  * @version: tvlv handler version to be unregistered
564  */
565 void batadv_tvlv_handler_unregister(struct batadv_priv *bat_priv,
566 				    u8 type, u8 version)
567 {
568 	struct batadv_tvlv_handler *tvlv_handler;
569 
570 	tvlv_handler = batadv_tvlv_handler_get(bat_priv, type, version);
571 	if (!tvlv_handler)
572 		return;
573 
574 	batadv_tvlv_handler_put(tvlv_handler);
575 	spin_lock_bh(&bat_priv->tvlv.handler_list_lock);
576 	hlist_del_rcu(&tvlv_handler->list);
577 	spin_unlock_bh(&bat_priv->tvlv.handler_list_lock);
578 	batadv_tvlv_handler_put(tvlv_handler);
579 }
580 
581 /**
582  * batadv_tvlv_unicast_send - send a unicast packet with tvlv payload to the
583  *  specified host
584  * @bat_priv: the bat priv with all the soft interface information
585  * @src: source mac address of the unicast packet
586  * @dst: destination mac address of the unicast packet
587  * @type: tvlv type
588  * @version: tvlv version
589  * @tvlv_value: tvlv content
590  * @tvlv_value_len: tvlv content length
591  */
592 void batadv_tvlv_unicast_send(struct batadv_priv *bat_priv, u8 *src,
593 			      u8 *dst, u8 type, u8 version,
594 			      void *tvlv_value, u16 tvlv_value_len)
595 {
596 	struct batadv_unicast_tvlv_packet *unicast_tvlv_packet;
597 	struct batadv_tvlv_hdr *tvlv_hdr;
598 	struct batadv_orig_node *orig_node;
599 	struct sk_buff *skb;
600 	unsigned char *tvlv_buff;
601 	unsigned int tvlv_len;
602 	ssize_t hdr_len = sizeof(*unicast_tvlv_packet);
603 
604 	orig_node = batadv_orig_hash_find(bat_priv, dst);
605 	if (!orig_node)
606 		return;
607 
608 	tvlv_len = sizeof(*tvlv_hdr) + tvlv_value_len;
609 
610 	skb = netdev_alloc_skb_ip_align(NULL, ETH_HLEN + hdr_len + tvlv_len);
611 	if (!skb)
612 		goto out;
613 
614 	skb->priority = TC_PRIO_CONTROL;
615 	skb_reserve(skb, ETH_HLEN);
616 	tvlv_buff = skb_put(skb, sizeof(*unicast_tvlv_packet) + tvlv_len);
617 	unicast_tvlv_packet = (struct batadv_unicast_tvlv_packet *)tvlv_buff;
618 	unicast_tvlv_packet->packet_type = BATADV_UNICAST_TVLV;
619 	unicast_tvlv_packet->version = BATADV_COMPAT_VERSION;
620 	unicast_tvlv_packet->ttl = BATADV_TTL;
621 	unicast_tvlv_packet->reserved = 0;
622 	unicast_tvlv_packet->tvlv_len = htons(tvlv_len);
623 	unicast_tvlv_packet->align = 0;
624 	ether_addr_copy(unicast_tvlv_packet->src, src);
625 	ether_addr_copy(unicast_tvlv_packet->dst, dst);
626 
627 	tvlv_buff = (unsigned char *)(unicast_tvlv_packet + 1);
628 	tvlv_hdr = (struct batadv_tvlv_hdr *)tvlv_buff;
629 	tvlv_hdr->version = version;
630 	tvlv_hdr->type = type;
631 	tvlv_hdr->len = htons(tvlv_value_len);
632 	tvlv_buff += sizeof(*tvlv_hdr);
633 	memcpy(tvlv_buff, tvlv_value, tvlv_value_len);
634 
635 	batadv_send_skb_to_orig(skb, orig_node, NULL);
636 out:
637 	batadv_orig_node_put(orig_node);
638 }
639