summaryrefslogtreecommitdiff
path: root/net/batman-adv/bat_iv_ogm.c
blob: 468bd5e1f7f51e2b63e3dac97b27c8b625a5f94f (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
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
/*
 * Copyright (C) 2007-2011 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, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA
 *
 */

#include "main.h"
#include "bat_ogm.h"
#include "translation-table.h"
#include "ring_buffer.h"
#include "originator.h"
#include "routing.h"
#include "gateway_common.h"
#include "gateway_client.h"
#include "hard-interface.h"
#include "send.h"

void bat_ogm_init(struct hard_iface *hard_iface)
{
	struct batman_ogm_packet *batman_ogm_packet;

	hard_iface->packet_len = BATMAN_OGM_LEN;
	hard_iface->packet_buff = kmalloc(hard_iface->packet_len, GFP_ATOMIC);

	batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
	batman_ogm_packet->packet_type = BAT_OGM;
	batman_ogm_packet->version = COMPAT_VERSION;
	batman_ogm_packet->flags = NO_FLAGS;
	batman_ogm_packet->ttl = 2;
	batman_ogm_packet->tq = TQ_MAX_VALUE;
	batman_ogm_packet->tt_num_changes = 0;
	batman_ogm_packet->ttvn = 0;
}

void bat_ogm_init_primary(struct hard_iface *hard_iface)
{
	struct batman_ogm_packet *batman_ogm_packet;

	batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
	batman_ogm_packet->flags = PRIMARIES_FIRST_HOP;
	batman_ogm_packet->ttl = TTL;
}

void bat_ogm_update_mac(struct hard_iface *hard_iface)
{
	struct batman_ogm_packet *batman_ogm_packet;

	batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
	memcpy(batman_ogm_packet->orig,
	       hard_iface->net_dev->dev_addr, ETH_ALEN);
	memcpy(batman_ogm_packet->prev_sender,
	       hard_iface->net_dev->dev_addr, ETH_ALEN);
}

/* is there another aggregated packet here? */
static int bat_ogm_aggr_packet(int buff_pos, int packet_len,
			       int tt_num_changes)
{
	int next_buff_pos = buff_pos + BATMAN_OGM_LEN + tt_len(tt_num_changes);

	return (next_buff_pos <= packet_len) &&
		(next_buff_pos <= MAX_AGGREGATION_BYTES);
}

static void bat_ogm_orig_update(struct bat_priv *bat_priv,
				struct orig_node *orig_node,
				const struct ethhdr *ethhdr,
				const struct batman_ogm_packet
							*batman_ogm_packet,
				struct hard_iface *if_incoming,
				const unsigned char *tt_buff, int is_duplicate)
{
	struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
	struct neigh_node *router = NULL;
	struct orig_node *orig_node_tmp;
	struct hlist_node *node;
	uint8_t bcast_own_sum_orig, bcast_own_sum_neigh;

	bat_dbg(DBG_BATMAN, bat_priv, "update_originator(): "
		"Searching and updating originator entry of received packet\n");

	rcu_read_lock();
	hlist_for_each_entry_rcu(tmp_neigh_node, node,
				 &orig_node->neigh_list, list) {
		if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) &&
		    (tmp_neigh_node->if_incoming == if_incoming) &&
		     atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
			if (neigh_node)
				neigh_node_free_ref(neigh_node);
			neigh_node = tmp_neigh_node;
			continue;
		}

		if (is_duplicate)
			continue;

		spin_lock_bh(&tmp_neigh_node->tq_lock);
		ring_buffer_set(tmp_neigh_node->tq_recv,
				&tmp_neigh_node->tq_index, 0);
		tmp_neigh_node->tq_avg =
			ring_buffer_avg(tmp_neigh_node->tq_recv);
		spin_unlock_bh(&tmp_neigh_node->tq_lock);
	}

	if (!neigh_node) {
		struct orig_node *orig_tmp;

		orig_tmp = get_orig_node(bat_priv, ethhdr->h_source);
		if (!orig_tmp)
			goto unlock;

		neigh_node = create_neighbor(orig_node, orig_tmp,
					     ethhdr->h_source, if_incoming);

		orig_node_free_ref(orig_tmp);
		if (!neigh_node)
			goto unlock;
	} else
		bat_dbg(DBG_BATMAN, bat_priv,
			"Updating existing last-hop neighbor of originator\n");

	rcu_read_unlock();

	orig_node->flags = batman_ogm_packet->flags;
	neigh_node->last_valid = jiffies;

	spin_lock_bh(&neigh_node->tq_lock);
	ring_buffer_set(neigh_node->tq_recv,
			&neigh_node->tq_index,
			batman_ogm_packet->tq);
	neigh_node->tq_avg = ring_buffer_avg(neigh_node->tq_recv);
	spin_unlock_bh(&neigh_node->tq_lock);

	if (!is_duplicate) {
		orig_node->last_ttl = batman_ogm_packet->ttl;
		neigh_node->last_ttl = batman_ogm_packet->ttl;
	}

	bonding_candidate_add(orig_node, neigh_node);

	/* if this neighbor already is our next hop there is nothing
	 * to change */
	router = orig_node_get_router(orig_node);
	if (router == neigh_node)
		goto update_tt;

	/* if this neighbor does not offer a better TQ we won't consider it */
	if (router && (router->tq_avg > neigh_node->tq_avg))
		goto update_tt;

	/* if the TQ is the same and the link not more symmetric we
	 * won't consider it either */
	if (router && (neigh_node->tq_avg == router->tq_avg)) {
		orig_node_tmp = router->orig_node;
		spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
		bcast_own_sum_orig =
			orig_node_tmp->bcast_own_sum[if_incoming->if_num];
		spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);

		orig_node_tmp = neigh_node->orig_node;
		spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
		bcast_own_sum_neigh =
			orig_node_tmp->bcast_own_sum[if_incoming->if_num];
		spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);

		if (bcast_own_sum_orig >= bcast_own_sum_neigh)
			goto update_tt;
	}

	update_route(bat_priv, orig_node, neigh_node);

update_tt:
	/* I have to check for transtable changes only if the OGM has been
	 * sent through a primary interface */
	if (((batman_ogm_packet->orig != ethhdr->h_source) &&
	     (batman_ogm_packet->ttl > 2)) ||
	    (batman_ogm_packet->flags & PRIMARIES_FIRST_HOP))
		tt_update_orig(bat_priv, orig_node, tt_buff,
			       batman_ogm_packet->tt_num_changes,
			       batman_ogm_packet->ttvn,
			       batman_ogm_packet->tt_crc);

	if (orig_node->gw_flags != batman_ogm_packet->gw_flags)
		gw_node_update(bat_priv, orig_node,
			       batman_ogm_packet->gw_flags);

	orig_node->gw_flags = batman_ogm_packet->gw_flags;

	/* restart gateway selection if fast or late switching was enabled */
	if ((orig_node->gw_flags) &&
	    (atomic_read(&bat_priv->gw_mode) == GW_MODE_CLIENT) &&
	    (atomic_read(&bat_priv->gw_sel_class) > 2))
		gw_check_election(bat_priv, orig_node);

	goto out;

unlock:
	rcu_read_unlock();
out:
	if (neigh_node)
		neigh_node_free_ref(neigh_node);
	if (router)
		neigh_node_free_ref(router);
}

static int bat_ogm_calc_tq(struct orig_node *orig_node,
			   struct orig_node *orig_neigh_node,
			   struct batman_ogm_packet *batman_ogm_packet,
			   struct hard_iface *if_incoming)
{
	struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
	struct neigh_node *neigh_node = NULL, *tmp_neigh_node;
	struct hlist_node *node;
	uint8_t total_count;
	uint8_t orig_eq_count, neigh_rq_count, tq_own;
	int tq_asym_penalty, ret = 0;

	/* find corresponding one hop neighbor */
	rcu_read_lock();
	hlist_for_each_entry_rcu(tmp_neigh_node, node,
				 &orig_neigh_node->neigh_list, list) {

		if (!compare_eth(tmp_neigh_node->addr, orig_neigh_node->orig))
			continue;

		if (tmp_neigh_node->if_incoming != if_incoming)
			continue;

		if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
			continue;

		neigh_node = tmp_neigh_node;
		break;
	}
	rcu_read_unlock();

	if (!neigh_node)
		neigh_node = create_neighbor(orig_neigh_node,
					     orig_neigh_node,
					     orig_neigh_node->orig,
					     if_incoming);

	if (!neigh_node)
		goto out;

	/* if orig_node is direct neighbor update neigh_node last_valid */
	if (orig_node == orig_neigh_node)
		neigh_node->last_valid = jiffies;

	orig_node->last_valid = jiffies;

	/* find packet count of corresponding one hop neighbor */
	spin_lock_bh(&orig_node->ogm_cnt_lock);
	orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num];
	neigh_rq_count = neigh_node->real_packet_count;
	spin_unlock_bh(&orig_node->ogm_cnt_lock);

	/* pay attention to not get a value bigger than 100 % */
	total_count = (orig_eq_count > neigh_rq_count ?
		       neigh_rq_count : orig_eq_count);

	/* if we have too few packets (too less data) we set tq_own to zero */
	/* if we receive too few packets it is not considered bidirectional */
	if ((total_count < TQ_LOCAL_BIDRECT_SEND_MINIMUM) ||
	    (neigh_rq_count < TQ_LOCAL_BIDRECT_RECV_MINIMUM))
		tq_own = 0;
	else
		/* neigh_node->real_packet_count is never zero as we
		 * only purge old information when getting new
		 * information */
		tq_own = (TQ_MAX_VALUE * total_count) /	neigh_rq_count;

	/*
	 * 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
	 * affect the nearly-symmetric links only a little, but
	 * punishes asymmetric links more.  This will give a value
	 * between 0 and TQ_MAX_VALUE
	 */
	tq_asym_penalty = TQ_MAX_VALUE - (TQ_MAX_VALUE *
				(TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) *
				(TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) *
				(TQ_LOCAL_WINDOW_SIZE - neigh_rq_count)) /
					(TQ_LOCAL_WINDOW_SIZE *
					 TQ_LOCAL_WINDOW_SIZE *
					 TQ_LOCAL_WINDOW_SIZE);

	batman_ogm_packet->tq = ((batman_ogm_packet->tq * tq_own
							* tq_asym_penalty) /
						(TQ_MAX_VALUE * TQ_MAX_VALUE));

	bat_dbg(DBG_BATMAN, bat_priv,
		"bidirectional: "
		"orig = %-15pM neigh = %-15pM => own_bcast = %2i, "
		"real recv = %2i, local tq: %3i, asym_penalty: %3i, "
		"total tq: %3i\n",
		orig_node->orig, orig_neigh_node->orig, total_count,
		neigh_rq_count, tq_own,	tq_asym_penalty, batman_ogm_packet->tq);

	/* if link has the minimum required transmission quality
	 * consider it bidirectional */
	if (batman_ogm_packet->tq >= TQ_TOTAL_BIDRECT_LIMIT)
		ret = 1;

out:
	if (neigh_node)
		neigh_node_free_ref(neigh_node);
	return ret;
}

/* processes a batman packet for all interfaces, adjusts the sequence number and
 * finds out whether it is a duplicate.
 * returns:
 *   1 the packet is a duplicate
 *   0 the packet has not yet been received
 *  -1 the packet is old and has been received while the seqno window
 *     was protected. Caller should drop it.
 */
static int bat_ogm_update_seqnos(const struct ethhdr *ethhdr,
				 const struct batman_ogm_packet
							*batman_ogm_packet,
				 const struct hard_iface *if_incoming)
{
	struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
	struct orig_node *orig_node;
	struct neigh_node *tmp_neigh_node;
	struct hlist_node *node;
	int is_duplicate = 0;
	int32_t seq_diff;
	int need_update = 0;
	int set_mark, ret = -1;

	orig_node = get_orig_node(bat_priv, batman_ogm_packet->orig);
	if (!orig_node)
		return 0;

	spin_lock_bh(&orig_node->ogm_cnt_lock);
	seq_diff = batman_ogm_packet->seqno - orig_node->last_real_seqno;

	/* signalize caller that the packet is to be dropped. */
	if (window_protected(bat_priv, seq_diff,
			     &orig_node->batman_seqno_reset))
		goto out;

	rcu_read_lock();
	hlist_for_each_entry_rcu(tmp_neigh_node, node,
				 &orig_node->neigh_list, list) {

		is_duplicate |= get_bit_status(tmp_neigh_node->real_bits,
					       orig_node->last_real_seqno,
					       batman_ogm_packet->seqno);

		if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) &&
		    (tmp_neigh_node->if_incoming == if_incoming))
			set_mark = 1;
		else
			set_mark = 0;

		/* if the window moved, set the update flag. */
		need_update |= bit_get_packet(bat_priv,
					      tmp_neigh_node->real_bits,
					      seq_diff, set_mark);

		tmp_neigh_node->real_packet_count =
			bit_packet_count(tmp_neigh_node->real_bits);
	}
	rcu_read_unlock();

	if (need_update) {
		bat_dbg(DBG_BATMAN, bat_priv,
			"updating last_seqno: old %d, new %d\n",
			orig_node->last_real_seqno, batman_ogm_packet->seqno);
		orig_node->last_real_seqno = batman_ogm_packet->seqno;
	}

	ret = is_duplicate;

out:
	spin_unlock_bh(&orig_node->ogm_cnt_lock);
	orig_node_free_ref(orig_node);
	return ret;
}

static void bat_ogm_process(const struct ethhdr *ethhdr,
			    struct batman_ogm_packet *batman_ogm_packet,
			    const unsigned char *tt_buff,
			    struct hard_iface *if_incoming)
{
	struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
	struct hard_iface *hard_iface;
	struct orig_node *orig_neigh_node, *orig_node;
	struct neigh_node *router = NULL, *router_router = NULL;
	struct neigh_node *orig_neigh_router = NULL;
	int has_directlink_flag;
	int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
	int is_broadcast = 0, is_bidirectional, is_single_hop_neigh;
	int is_duplicate;
	uint32_t if_incoming_seqno;

	/* Silently drop when the batman packet is actually not a
	 * correct packet.
	 *
	 * This might happen if a packet is padded (e.g. Ethernet has a
	 * minimum frame length of 64 byte) and the aggregation interprets
	 * it as an additional length.
	 *
	 * TODO: A more sane solution would be to have a bit in the
	 * batman_ogm_packet to detect whether the packet is the last
	 * packet in an aggregation.  Here we expect that the padding
	 * is always zero (or not 0x01)
	 */
	if (batman_ogm_packet->packet_type != BAT_OGM)
		return;

	/* could be changed by schedule_own_packet() */
	if_incoming_seqno = atomic_read(&if_incoming->seqno);

	has_directlink_flag = (batman_ogm_packet->flags & DIRECTLINK ? 1 : 0);

	is_single_hop_neigh = (compare_eth(ethhdr->h_source,
					   batman_ogm_packet->orig) ? 1 : 0);

	bat_dbg(DBG_BATMAN, bat_priv,
		"Received BATMAN packet via NB: %pM, IF: %s [%pM] "
		"(from OG: %pM, via prev OG: %pM, seqno %d, ttvn %u, "
		"crc %u, changes %u, td %d, TTL %d, V %d, IDF %d)\n",
		ethhdr->h_source, if_incoming->net_dev->name,
		if_incoming->net_dev->dev_addr, batman_ogm_packet->orig,
		batman_ogm_packet->prev_sender, batman_ogm_packet->seqno,
		batman_ogm_packet->ttvn, batman_ogm_packet->tt_crc,
		batman_ogm_packet->tt_num_changes, batman_ogm_packet->tq,
		batman_ogm_packet->ttl, batman_ogm_packet->version,
		has_directlink_flag);

	rcu_read_lock();
	list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
		if (hard_iface->if_status != IF_ACTIVE)
			continue;

		if (hard_iface->soft_iface != if_incoming->soft_iface)
			continue;

		if (compare_eth(ethhdr->h_source,
				hard_iface->net_dev->dev_addr))
			is_my_addr = 1;

		if (compare_eth(batman_ogm_packet->orig,
				hard_iface->net_dev->dev_addr))
			is_my_orig = 1;

		if (compare_eth(batman_ogm_packet->prev_sender,
				hard_iface->net_dev->dev_addr))
			is_my_oldorig = 1;

		if (is_broadcast_ether_addr(ethhdr->h_source))
			is_broadcast = 1;
	}
	rcu_read_unlock();

	if (batman_ogm_packet->version != COMPAT_VERSION) {
		bat_dbg(DBG_BATMAN, bat_priv,
			"Drop packet: incompatible batman version (%i)\n",
			batman_ogm_packet->version);
		return;
	}

	if (is_my_addr) {
		bat_dbg(DBG_BATMAN, bat_priv,
			"Drop packet: received my own broadcast (sender: %pM"
			")\n",
			ethhdr->h_source);
		return;
	}

	if (is_broadcast) {
		bat_dbg(DBG_BATMAN, bat_priv, "Drop packet: "
		"ignoring all packets with broadcast source addr (sender: %pM"
		")\n", ethhdr->h_source);
		return;
	}

	if (is_my_orig) {
		unsigned long *word;
		int offset;

		orig_neigh_node = get_orig_node(bat_priv, ethhdr->h_source);
		if (!orig_neigh_node)
			return;

		/* neighbor has to indicate direct link and it has to
		 * come via the corresponding interface */
		/* save packet seqno for bidirectional check */
		if (has_directlink_flag &&
		    compare_eth(if_incoming->net_dev->dev_addr,
				batman_ogm_packet->orig)) {
			offset = if_incoming->if_num * NUM_WORDS;

			spin_lock_bh(&orig_neigh_node->ogm_cnt_lock);
			word = &(orig_neigh_node->bcast_own[offset]);
			bit_mark(word,
				 if_incoming_seqno -
						batman_ogm_packet->seqno - 2);
			orig_neigh_node->bcast_own_sum[if_incoming->if_num] =
				bit_packet_count(word);
			spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);
		}

		bat_dbg(DBG_BATMAN, bat_priv, "Drop packet: "
			"originator packet from myself (via neighbor)\n");
		orig_node_free_ref(orig_neigh_node);
		return;
	}

	if (is_my_oldorig) {
		bat_dbg(DBG_BATMAN, bat_priv,
			"Drop packet: ignoring all rebroadcast echos (sender: "
			"%pM)\n", ethhdr->h_source);
		return;
	}

	orig_node = get_orig_node(bat_priv, batman_ogm_packet->orig);
	if (!orig_node)
		return;

	is_duplicate = bat_ogm_update_seqnos(ethhdr, batman_ogm_packet,
					     if_incoming);

	if (is_duplicate == -1) {
		bat_dbg(DBG_BATMAN, bat_priv,
			"Drop packet: packet within seqno protection time "
			"(sender: %pM)\n", ethhdr->h_source);
		goto out;
	}

	if (batman_ogm_packet->tq == 0) {
		bat_dbg(DBG_BATMAN, bat_priv,
			"Drop packet: originator packet with tq equal 0\n");
		goto out;
	}

	router = orig_node_get_router(orig_node);
	if (router)
		router_router = orig_node_get_router(router->orig_node);

	/* avoid temporary routing loops */
	if (router && router_router &&
	    (compare_eth(router->addr, batman_ogm_packet->prev_sender)) &&
	    !(compare_eth(batman_ogm_packet->orig,
			  batman_ogm_packet->prev_sender)) &&
	    (compare_eth(router->addr, router_router->addr))) {
		bat_dbg(DBG_BATMAN, bat_priv,
			"Drop packet: ignoring all rebroadcast packets that "
			"may make me loop (sender: %pM)\n", ethhdr->h_source);
		goto out;
	}

	/* if sender is a direct neighbor the sender mac equals
	 * originator mac */
	orig_neigh_node = (is_single_hop_neigh ?
			   orig_node :
			   get_orig_node(bat_priv, ethhdr->h_source));
	if (!orig_neigh_node)
		goto out;

	orig_neigh_router = orig_node_get_router(orig_neigh_node);

	/* drop packet if sender is not a direct neighbor and if we
	 * don't route towards it */
	if (!is_single_hop_neigh && (!orig_neigh_router)) {
		bat_dbg(DBG_BATMAN, bat_priv,
			"Drop packet: OGM via unknown neighbor!\n");
		goto out_neigh;
	}

	is_bidirectional = bat_ogm_calc_tq(orig_node, orig_neigh_node,
					   batman_ogm_packet, if_incoming);

	bonding_save_primary(orig_node, orig_neigh_node, batman_ogm_packet);

	/* update ranking if it is not a duplicate or has the same
	 * seqno and similar ttl as the non-duplicate */
	if (is_bidirectional &&
	    (!is_duplicate ||
	     ((orig_node->last_real_seqno == batman_ogm_packet->seqno) &&
	      (orig_node->last_ttl - 3 <= batman_ogm_packet->ttl))))
		bat_ogm_orig_update(bat_priv, orig_node, ethhdr,
				    batman_ogm_packet, if_incoming,
				    tt_buff, is_duplicate);

	/* is single hop (direct) neighbor */
	if (is_single_hop_neigh) {

		/* mark direct link on incoming interface */
		schedule_forward_packet(orig_node, ethhdr, batman_ogm_packet,
					1, if_incoming);

		bat_dbg(DBG_BATMAN, bat_priv, "Forwarding packet: "
			"rebroadcast neighbor packet with direct link flag\n");
		goto out_neigh;
	}

	/* multihop originator */
	if (!is_bidirectional) {
		bat_dbg(DBG_BATMAN, bat_priv,
			"Drop packet: not received via bidirectional link\n");
		goto out_neigh;
	}

	if (is_duplicate) {
		bat_dbg(DBG_BATMAN, bat_priv,
			"Drop packet: duplicate packet received\n");
		goto out_neigh;
	}

	bat_dbg(DBG_BATMAN, bat_priv,
		"Forwarding packet: rebroadcast originator packet\n");
	schedule_forward_packet(orig_node, ethhdr, batman_ogm_packet,
				0, if_incoming);

out_neigh:
	if ((orig_neigh_node) && (!is_single_hop_neigh))
		orig_node_free_ref(orig_neigh_node);
out:
	if (router)
		neigh_node_free_ref(router);
	if (router_router)
		neigh_node_free_ref(router_router);
	if (orig_neigh_router)
		neigh_node_free_ref(orig_neigh_router);

	orig_node_free_ref(orig_node);
}

void bat_ogm_receive(const struct ethhdr *ethhdr, unsigned char *packet_buff,
		     int packet_len, struct hard_iface *if_incoming)
{
	struct batman_ogm_packet *batman_ogm_packet;
	int buff_pos = 0;
	unsigned char *tt_buff;

	batman_ogm_packet = (struct batman_ogm_packet *)packet_buff;

	/* unpack the aggregated packets and process them one by one */
	do {
		/* network to host order for our 32bit seqno and the
		   orig_interval */
		batman_ogm_packet->seqno = ntohl(batman_ogm_packet->seqno);
		batman_ogm_packet->tt_crc = ntohs(batman_ogm_packet->tt_crc);

		tt_buff = packet_buff + buff_pos + BATMAN_OGM_LEN;

		bat_ogm_process(ethhdr, batman_ogm_packet,
				tt_buff, if_incoming);

		buff_pos += BATMAN_OGM_LEN +
				tt_len(batman_ogm_packet->tt_num_changes);

		batman_ogm_packet = (struct batman_ogm_packet *)
						(packet_buff + buff_pos);
	} while (bat_ogm_aggr_packet(buff_pos, packet_len,
				     batman_ogm_packet->tt_num_changes));
}