summaryrefslogtreecommitdiff
path: root/net/batman-adv/tvlv.c
blob: a783420356ae0cd4a6273b3b7a04781242e37a82 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
/* Copyright (C) 2007-2016  B.A.T.M.A.N. contributors:
 *
 * Marek Lindner, Simon Wunderlich
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

#include "main.h"

#include <linux/byteorder/generic.h>
#include <linux/etherdevice.h>
#include <linux/fs.h>
#include <linux/if_ether.h>
#include <linux/kernel.h>
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/lockdep.h>
#include <linux/netdevice.h>
#include <linux/pkt_sched.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <linux/types.h>

#include "originator.h"
#include "packet.h"
#include "send.h"
#include "tvlv.h"

/**
 * batadv_tvlv_handler_release - release tvlv handler from lists and queue for
 *  free after rcu grace period
 * @ref: kref pointer of the tvlv
 */
static void batadv_tvlv_handler_release(struct kref *ref)
{
	struct batadv_tvlv_handler *tvlv_handler;

	tvlv_handler = container_of(ref, struct batadv_tvlv_handler, refcount);
	kfree_rcu(tvlv_handler, rcu);
}

/**
 * batadv_tvlv_handler_put - decrement the tvlv container refcounter and
 *  possibly release it
 * @tvlv_handler: the tvlv handler to free
 */
static void batadv_tvlv_handler_put(struct batadv_tvlv_handler *tvlv_handler)
{
	kref_put(&tvlv_handler->refcount, batadv_tvlv_handler_release);
}

/**
 * batadv_tvlv_handler_get - retrieve tvlv handler from the tvlv handler list
 *  based on the provided type and version (both need to match)
 * @bat_priv: the bat priv with all the soft interface information
 * @type: tvlv handler type to look for
 * @version: tvlv handler version to look for
 *
 * Return: tvlv handler if found or NULL otherwise.
 */
static struct batadv_tvlv_handler *
batadv_tvlv_handler_get(struct batadv_priv *bat_priv, u8 type, u8 version)
{
	struct batadv_tvlv_handler *tvlv_handler_tmp, *tvlv_handler = NULL;

	rcu_read_lock();
	hlist_for_each_entry_rcu(tvlv_handler_tmp,
				 &bat_priv->tvlv.handler_list, list) {
		if (tvlv_handler_tmp->type != type)
			continue;

		if (tvlv_handler_tmp->version != version)
			continue;

		if (!kref_get_unless_zero(&tvlv_handler_tmp->refcount))
			continue;

		tvlv_handler = tvlv_handler_tmp;
		break;
	}
	rcu_read_unlock();

	return tvlv_handler;
}

/**
 * batadv_tvlv_container_release - release tvlv from lists and free
 * @ref: kref pointer of the tvlv
 */
static void batadv_tvlv_container_release(struct kref *ref)
{
	struct batadv_tvlv_container *tvlv;

	tvlv = container_of(ref, struct batadv_tvlv_container, refcount);
	kfree(tvlv);
}

/**
 * batadv_tvlv_container_put - decrement the tvlv container refcounter and
 *  possibly release it
 * @tvlv: the tvlv container to free
 */
static void batadv_tvlv_container_put(struct batadv_tvlv_container *tvlv)
{
	kref_put(&tvlv->refcount, batadv_tvlv_container_release);
}

/**
 * batadv_tvlv_container_get - retrieve tvlv container from the tvlv container
 *  list based on the provided type and version (both need to match)
 * @bat_priv: the bat priv with all the soft interface information
 * @type: tvlv container type to look for
 * @version: tvlv container version to look for
 *
 * Has to be called with the appropriate locks being acquired
 * (tvlv.container_list_lock).
 *
 * Return: tvlv container if found or NULL otherwise.
 */
static struct batadv_tvlv_container *
batadv_tvlv_container_get(struct batadv_priv *bat_priv, u8 type, u8 version)
{
	struct batadv_tvlv_container *tvlv_tmp, *tvlv = NULL;

	lockdep_assert_held(&bat_priv->tvlv.container_list_lock);

	hlist_for_each_entry(tvlv_tmp, &bat_priv->tvlv.container_list, list) {
		if (tvlv_tmp->tvlv_hdr.type != type)
			continue;

		if (tvlv_tmp->tvlv_hdr.version != version)
			continue;

		kref_get(&tvlv_tmp->refcount);
		tvlv = tvlv_tmp;
		break;
	}

	return tvlv;
}

/**
 * batadv_tvlv_container_list_size - calculate the size of the tvlv container
 *  list entries
 * @bat_priv: the bat priv with all the soft interface information
 *
 * Has to be called with the appropriate locks being acquired
 * (tvlv.container_list_lock).
 *
 * Return: size of all currently registered tvlv containers in bytes.
 */
static u16 batadv_tvlv_container_list_size(struct batadv_priv *bat_priv)
{
	struct batadv_tvlv_container *tvlv;
	u16 tvlv_len = 0;

	lockdep_assert_held(&bat_priv->tvlv.container_list_lock);

	hlist_for_each_entry(tvlv, &bat_priv->tvlv.container_list, list) {
		tvlv_len += sizeof(struct batadv_tvlv_hdr);
		tvlv_len += ntohs(tvlv->tvlv_hdr.len);
	}

	return tvlv_len;
}

/**
 * batadv_tvlv_container_remove - remove tvlv container from the tvlv container
 *  list
 * @bat_priv: the bat priv with all the soft interface information
 * @tvlv: the to be removed tvlv container
 *
 * Has to be called with the appropriate locks being acquired
 * (tvlv.container_list_lock).
 */
static void batadv_tvlv_container_remove(struct batadv_priv *bat_priv,
					 struct batadv_tvlv_container *tvlv)
{
	lockdep_assert_held(&bat_priv->tvlv.container_list_lock);

	if (!tvlv)
		return;

	hlist_del(&tvlv->list);

	/* first call to decrement the counter, second call to free */
	batadv_tvlv_container_put(tvlv);
	batadv_tvlv_container_put(tvlv);
}

/**
 * batadv_tvlv_container_unregister - unregister tvlv container based on the
 *  provided type and version (both need to match)
 * @bat_priv: the bat priv with all the soft interface information
 * @type: tvlv container type to unregister
 * @version: tvlv container type to unregister
 */
void batadv_tvlv_container_unregister(struct batadv_priv *bat_priv,
				      u8 type, u8 version)
{
	struct batadv_tvlv_container *tvlv;

	spin_lock_bh(&bat_priv->tvlv.container_list_lock);
	tvlv = batadv_tvlv_container_get(bat_priv, type, version);
	batadv_tvlv_container_remove(bat_priv, tvlv);
	spin_unlock_bh(&bat_priv->tvlv.container_list_lock);
}

/**
 * batadv_tvlv_container_register - register tvlv type, version and content
 *  to be propagated with each (primary interface) OGM
 * @bat_priv: the bat priv with all the soft interface information
 * @type: tvlv container type
 * @version: tvlv container version
 * @tvlv_value: tvlv container content
 * @tvlv_value_len: tvlv container content length
 *
 * If a container of the same type and version was already registered the new
 * content is going to replace the old one.
 */
void batadv_tvlv_container_register(struct batadv_priv *bat_priv,
				    u8 type, u8 version,
				    void *tvlv_value, u16 tvlv_value_len)
{
	struct batadv_tvlv_container *tvlv_old, *tvlv_new;

	if (!tvlv_value)
		tvlv_value_len = 0;

	tvlv_new = kzalloc(sizeof(*tvlv_new) + tvlv_value_len, GFP_ATOMIC);
	if (!tvlv_new)
		return;

	tvlv_new->tvlv_hdr.version = version;
	tvlv_new->tvlv_hdr.type = type;
	tvlv_new->tvlv_hdr.len = htons(tvlv_value_len);

	memcpy(tvlv_new + 1, tvlv_value, ntohs(tvlv_new->tvlv_hdr.len));
	INIT_HLIST_NODE(&tvlv_new->list);
	kref_init(&tvlv_new->refcount);

	spin_lock_bh(&bat_priv->tvlv.container_list_lock);
	tvlv_old = batadv_tvlv_container_get(bat_priv, type, version);
	batadv_tvlv_container_remove(bat_priv, tvlv_old);

	kref_get(&tvlv_new->refcount);
	hlist_add_head(&tvlv_new->list, &bat_priv->tvlv.container_list);
	spin_unlock_bh(&bat_priv->tvlv.container_list_lock);

	/* don't return reference to new tvlv_container */
	batadv_tvlv_container_put(tvlv_new);
}

/**
 * batadv_tvlv_realloc_packet_buff - reallocate packet buffer to accommodate
 *  requested packet size
 * @packet_buff: packet buffer
 * @packet_buff_len: packet buffer size
 * @min_packet_len: requested packet minimum size
 * @additional_packet_len: requested additional packet size on top of minimum
 *  size
 *
 * Return: true of the packet buffer could be changed to the requested size,
 * false otherwise.
 */
static bool batadv_tvlv_realloc_packet_buff(unsigned char **packet_buff,
					    int *packet_buff_len,
					    int min_packet_len,
					    int additional_packet_len)
{
	unsigned char *new_buff;

	new_buff = kmalloc(min_packet_len + additional_packet_len, GFP_ATOMIC);

	/* keep old buffer if kmalloc should fail */
	if (!new_buff)
		return false;

	memcpy(new_buff, *packet_buff, min_packet_len);
	kfree(*packet_buff);
	*packet_buff = new_buff;
	*packet_buff_len = min_packet_len + additional_packet_len;

	return true;
}

/**
 * batadv_tvlv_container_ogm_append - append tvlv container content to given
 *  OGM packet buffer
 * @bat_priv: the bat priv with all the soft interface information
 * @packet_buff: ogm packet buffer
 * @packet_buff_len: ogm packet buffer size including ogm header and tvlv
 *  content
 * @packet_min_len: ogm header size to be preserved for the OGM itself
 *
 * The ogm packet might be enlarged or shrunk depending on the current size
 * and the size of the to-be-appended tvlv containers.
 *
 * Return: size of all appended tvlv containers in bytes.
 */
u16 batadv_tvlv_container_ogm_append(struct batadv_priv *bat_priv,
				     unsigned char **packet_buff,
				     int *packet_buff_len, int packet_min_len)
{
	struct batadv_tvlv_container *tvlv;
	struct batadv_tvlv_hdr *tvlv_hdr;
	u16 tvlv_value_len;
	void *tvlv_value;
	bool ret;

	spin_lock_bh(&bat_priv->tvlv.container_list_lock);
	tvlv_value_len = batadv_tvlv_container_list_size(bat_priv);

	ret = batadv_tvlv_realloc_packet_buff(packet_buff, packet_buff_len,
					      packet_min_len, tvlv_value_len);

	if (!ret)
		goto end;

	if (!tvlv_value_len)
		goto end;

	tvlv_value = (*packet_buff) + packet_min_len;

	hlist_for_each_entry(tvlv, &bat_priv->tvlv.container_list, list) {
		tvlv_hdr = tvlv_value;
		tvlv_hdr->type = tvlv->tvlv_hdr.type;
		tvlv_hdr->version = tvlv->tvlv_hdr.version;
		tvlv_hdr->len = tvlv->tvlv_hdr.len;
		tvlv_value = tvlv_hdr + 1;
		memcpy(tvlv_value, tvlv + 1, ntohs(tvlv->tvlv_hdr.len));
		tvlv_value = (u8 *)tvlv_value + ntohs(tvlv->tvlv_hdr.len);
	}

end:
	spin_unlock_bh(&bat_priv->tvlv.container_list_lock);
	return tvlv_value_len;
}

/**
 * batadv_tvlv_call_handler - parse the given tvlv buffer to call the
 *  appropriate handlers
 * @bat_priv: the bat priv with all the soft interface information
 * @tvlv_handler: tvlv callback function handling the tvlv content
 * @ogm_source: flag indicating whether the tvlv is an ogm or a unicast packet
 * @orig_node: orig node emitting the ogm packet
 * @src: source mac address of the unicast packet
 * @dst: destination mac address of the unicast packet
 * @tvlv_value: tvlv content
 * @tvlv_value_len: tvlv content length
 *
 * Return: success if handler was not found or the return value of the handler
 * callback.
 */
static int batadv_tvlv_call_handler(struct batadv_priv *bat_priv,
				    struct batadv_tvlv_handler *tvlv_handler,
				    bool ogm_source,
				    struct batadv_orig_node *orig_node,
				    u8 *src, u8 *dst,
				    void *tvlv_value, u16 tvlv_value_len)
{
	if (!tvlv_handler)
		return NET_RX_SUCCESS;

	if (ogm_source) {
		if (!tvlv_handler->ogm_handler)
			return NET_RX_SUCCESS;

		if (!orig_node)
			return NET_RX_SUCCESS;

		tvlv_handler->ogm_handler(bat_priv, orig_node,
					  BATADV_NO_FLAGS,
					  tvlv_value, tvlv_value_len);
		tvlv_handler->flags |= BATADV_TVLV_HANDLER_OGM_CALLED;
	} else {
		if (!src)
			return NET_RX_SUCCESS;

		if (!dst)
			return NET_RX_SUCCESS;

		if (!tvlv_handler->unicast_handler)
			return NET_RX_SUCCESS;

		return tvlv_handler->unicast_handler(bat_priv, src,
						     dst, tvlv_value,
						     tvlv_value_len);
	}

	return NET_RX_SUCCESS;
}

/**
 * batadv_tvlv_containers_process - parse the given tvlv buffer to call the
 *  appropriate handlers
 * @bat_priv: the bat priv with all the soft interface information
 * @ogm_source: flag indicating whether the tvlv is an ogm or a unicast packet
 * @orig_node: orig node emitting the ogm packet
 * @src: source mac address of the unicast packet
 * @dst: destination mac address of the unicast packet
 * @tvlv_value: tvlv content
 * @tvlv_value_len: tvlv content length
 *
 * Return: success when processing an OGM or the return value of all called
 * handler callbacks.
 */
int batadv_tvlv_containers_process(struct batadv_priv *bat_priv,
				   bool ogm_source,
				   struct batadv_orig_node *orig_node,
				   u8 *src, u8 *dst,
				   void *tvlv_value, u16 tvlv_value_len)
{
	struct batadv_tvlv_handler *tvlv_handler;
	struct batadv_tvlv_hdr *tvlv_hdr;
	u16 tvlv_value_cont_len;
	u8 cifnotfound = BATADV_TVLV_HANDLER_OGM_CIFNOTFND;
	int ret = NET_RX_SUCCESS;

	while (tvlv_value_len >= sizeof(*tvlv_hdr)) {
		tvlv_hdr = tvlv_value;
		tvlv_value_cont_len = ntohs(tvlv_hdr->len);
		tvlv_value = tvlv_hdr + 1;
		tvlv_value_len -= sizeof(*tvlv_hdr);

		if (tvlv_value_cont_len > tvlv_value_len)
			break;

		tvlv_handler = batadv_tvlv_handler_get(bat_priv,
						       tvlv_hdr->type,
						       tvlv_hdr->version);

		ret |= batadv_tvlv_call_handler(bat_priv, tvlv_handler,
						ogm_source, orig_node,
						src, dst, tvlv_value,
						tvlv_value_cont_len);
		if (tvlv_handler)
			batadv_tvlv_handler_put(tvlv_handler);
		tvlv_value = (u8 *)tvlv_value + tvlv_value_cont_len;
		tvlv_value_len -= tvlv_value_cont_len;
	}

	if (!ogm_source)
		return ret;

	rcu_read_lock();
	hlist_for_each_entry_rcu(tvlv_handler,
				 &bat_priv->tvlv.handler_list, list) {
		if ((tvlv_handler->flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND) &&
		    !(tvlv_handler->flags & BATADV_TVLV_HANDLER_OGM_CALLED))
			tvlv_handler->ogm_handler(bat_priv, orig_node,
						  cifnotfound, NULL, 0);

		tvlv_handler->flags &= ~BATADV_TVLV_HANDLER_OGM_CALLED;
	}
	rcu_read_unlock();

	return NET_RX_SUCCESS;
}

/**
 * batadv_tvlv_ogm_receive - process an incoming ogm and call the appropriate
 *  handlers
 * @bat_priv: the bat priv with all the soft interface information
 * @batadv_ogm_packet: ogm packet containing the tvlv containers
 * @orig_node: orig node emitting the ogm packet
 */
void batadv_tvlv_ogm_receive(struct batadv_priv *bat_priv,
			     struct batadv_ogm_packet *batadv_ogm_packet,
			     struct batadv_orig_node *orig_node)
{
	void *tvlv_value;
	u16 tvlv_value_len;

	if (!batadv_ogm_packet)
		return;

	tvlv_value_len = ntohs(batadv_ogm_packet->tvlv_len);
	if (!tvlv_value_len)
		return;

	tvlv_value = batadv_ogm_packet + 1;

	batadv_tvlv_containers_process(bat_priv, true, orig_node, NULL, NULL,
				       tvlv_value, tvlv_value_len);
}

/**
 * batadv_tvlv_handler_register - register tvlv handler based on the provided
 *  type and version (both need to match) for ogm tvlv payload and/or unicast
 *  payload
 * @bat_priv: the bat priv with all the soft interface information
 * @optr: ogm tvlv handler callback function. This function receives the orig
 *  node, flags and the tvlv content as argument to process.
 * @uptr: unicast tvlv handler callback function. This function receives the
 *  source & destination of the unicast packet as well as the tvlv content
 *  to process.
 * @type: tvlv handler type to be registered
 * @version: tvlv handler version to be registered
 * @flags: flags to enable or disable TVLV API behavior
 */
void batadv_tvlv_handler_register(struct batadv_priv *bat_priv,
				  void (*optr)(struct batadv_priv *bat_priv,
					       struct batadv_orig_node *orig,
					       u8 flags,
					       void *tvlv_value,
					       u16 tvlv_value_len),
				  int (*uptr)(struct batadv_priv *bat_priv,
					      u8 *src, u8 *dst,
					      void *tvlv_value,
					      u16 tvlv_value_len),
				  u8 type, u8 version, u8 flags)
{
	struct batadv_tvlv_handler *tvlv_handler;

	tvlv_handler = batadv_tvlv_handler_get(bat_priv, type, version);
	if (tvlv_handler) {
		batadv_tvlv_handler_put(tvlv_handler);
		return;
	}

	tvlv_handler = kzalloc(sizeof(*tvlv_handler), GFP_ATOMIC);
	if (!tvlv_handler)
		return;

	tvlv_handler->ogm_handler = optr;
	tvlv_handler->unicast_handler = uptr;
	tvlv_handler->type = type;
	tvlv_handler->version = version;
	tvlv_handler->flags = flags;
	kref_init(&tvlv_handler->refcount);
	INIT_HLIST_NODE(&tvlv_handler->list);

	spin_lock_bh(&bat_priv->tvlv.handler_list_lock);
	kref_get(&tvlv_handler->refcount);
	hlist_add_head_rcu(&tvlv_handler->list, &bat_priv->tvlv.handler_list);
	spin_unlock_bh(&bat_priv->tvlv.handler_list_lock);

	/* don't return reference to new tvlv_handler */
	batadv_tvlv_handler_put(tvlv_handler);
}

/**
 * batadv_tvlv_handler_unregister - unregister tvlv handler based on the
 *  provided type and version (both need to match)
 * @bat_priv: the bat priv with all the soft interface information
 * @type: tvlv handler type to be unregistered
 * @version: tvlv handler version to be unregistered
 */
void batadv_tvlv_handler_unregister(struct batadv_priv *bat_priv,
				    u8 type, u8 version)
{
	struct batadv_tvlv_handler *tvlv_handler;

	tvlv_handler = batadv_tvlv_handler_get(bat_priv, type, version);
	if (!tvlv_handler)
		return;

	batadv_tvlv_handler_put(tvlv_handler);
	spin_lock_bh(&bat_priv->tvlv.handler_list_lock);
	hlist_del_rcu(&tvlv_handler->list);
	spin_unlock_bh(&bat_priv->tvlv.handler_list_lock);
	batadv_tvlv_handler_put(tvlv_handler);
}

/**
 * batadv_tvlv_unicast_send - send a unicast packet with tvlv payload to the
 *  specified host
 * @bat_priv: the bat priv with all the soft interface information
 * @src: source mac address of the unicast packet
 * @dst: destination mac address of the unicast packet
 * @type: tvlv type
 * @version: tvlv version
 * @tvlv_value: tvlv content
 * @tvlv_value_len: tvlv content length
 */
void batadv_tvlv_unicast_send(struct batadv_priv *bat_priv, u8 *src,
			      u8 *dst, u8 type, u8 version,
			      void *tvlv_value, u16 tvlv_value_len)
{
	struct batadv_unicast_tvlv_packet *unicast_tvlv_packet;
	struct batadv_tvlv_hdr *tvlv_hdr;
	struct batadv_orig_node *orig_node;
	struct sk_buff *skb;
	unsigned char *tvlv_buff;
	unsigned int tvlv_len;
	ssize_t hdr_len = sizeof(*unicast_tvlv_packet);

	orig_node = batadv_orig_hash_find(bat_priv, dst);
	if (!orig_node)
		return;

	tvlv_len = sizeof(*tvlv_hdr) + tvlv_value_len;

	skb = netdev_alloc_skb_ip_align(NULL, ETH_HLEN + hdr_len + tvlv_len);
	if (!skb)
		goto out;

	skb->priority = TC_PRIO_CONTROL;
	skb_reserve(skb, ETH_HLEN);
	tvlv_buff = skb_put(skb, sizeof(*unicast_tvlv_packet) + tvlv_len);
	unicast_tvlv_packet = (struct batadv_unicast_tvlv_packet *)tvlv_buff;
	unicast_tvlv_packet->packet_type = BATADV_UNICAST_TVLV;
	unicast_tvlv_packet->version = BATADV_COMPAT_VERSION;
	unicast_tvlv_packet->ttl = BATADV_TTL;
	unicast_tvlv_packet->reserved = 0;
	unicast_tvlv_packet->tvlv_len = htons(tvlv_len);
	unicast_tvlv_packet->align = 0;
	ether_addr_copy(unicast_tvlv_packet->src, src);
	ether_addr_copy(unicast_tvlv_packet->dst, dst);

	tvlv_buff = (unsigned char *)(unicast_tvlv_packet + 1);
	tvlv_hdr = (struct batadv_tvlv_hdr *)tvlv_buff;
	tvlv_hdr->version = version;
	tvlv_hdr->type = type;
	tvlv_hdr->len = htons(tvlv_value_len);
	tvlv_buff += sizeof(*tvlv_hdr);
	memcpy(tvlv_buff, tvlv_value, tvlv_value_len);

	batadv_send_skb_to_orig(skb, orig_node, NULL);
out:
	batadv_orig_node_put(orig_node);
}