summaryrefslogtreecommitdiff
path: root/net/batman-adv/send.c
blob: 9a20ba9e056fc47371c987cc645c26909bb89c1f (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
/*
 * 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 "send.h"
#include "routing.h"
#include "translation-table.h"
#include "soft-interface.h"
#include "hard-interface.h"
#include "vis.h"
#include "aggregation.h"
#include "gateway_common.h"
#include "originator.h"

static void send_outstanding_bcast_packet(struct work_struct *work);

/* apply hop penalty for a normal link */
static uint8_t hop_penalty(uint8_t tq, const struct bat_priv *bat_priv)
{
	int hop_penalty = atomic_read(&bat_priv->hop_penalty);
	return (tq * (TQ_MAX_VALUE - hop_penalty)) / (TQ_MAX_VALUE);
}

/* when do we schedule our own packet to be sent */
static unsigned long own_send_time(const struct bat_priv *bat_priv)
{
	return jiffies + msecs_to_jiffies(
		   atomic_read(&bat_priv->orig_interval) -
		   JITTER + (random32() % 2*JITTER));
}

/* when do we schedule a forwarded packet to be sent */
static unsigned long forward_send_time(void)
{
	return jiffies + msecs_to_jiffies(random32() % (JITTER/2));
}

/* send out an already prepared packet to the given address via the
 * specified batman interface */
int send_skb_packet(struct sk_buff *skb, struct hard_iface *hard_iface,
		    const uint8_t *dst_addr)
{
	struct ethhdr *ethhdr;

	if (hard_iface->if_status != IF_ACTIVE)
		goto send_skb_err;

	if (unlikely(!hard_iface->net_dev))
		goto send_skb_err;

	if (!(hard_iface->net_dev->flags & IFF_UP)) {
		pr_warning("Interface %s is not up - can't send packet via "
			   "that interface!\n", hard_iface->net_dev->name);
		goto send_skb_err;
	}

	/* push to the ethernet header. */
	if (my_skb_head_push(skb, sizeof(struct ethhdr)) < 0)
		goto send_skb_err;

	skb_reset_mac_header(skb);

	ethhdr = (struct ethhdr *) skb_mac_header(skb);
	memcpy(ethhdr->h_source, hard_iface->net_dev->dev_addr, ETH_ALEN);
	memcpy(ethhdr->h_dest, dst_addr, ETH_ALEN);
	ethhdr->h_proto = __constant_htons(ETH_P_BATMAN);

	skb_set_network_header(skb, ETH_HLEN);
	skb->priority = TC_PRIO_CONTROL;
	skb->protocol = __constant_htons(ETH_P_BATMAN);

	skb->dev = hard_iface->net_dev;

	/* dev_queue_xmit() returns a negative result on error.	 However on
	 * congestion and traffic shaping, it drops and returns NET_XMIT_DROP
	 * (which is > 0). This will not be treated as an error. */

	return dev_queue_xmit(skb);
send_skb_err:
	kfree_skb(skb);
	return NET_XMIT_DROP;
}

/* Send a packet to a given interface */
static void send_packet_to_if(struct forw_packet *forw_packet,
			      struct hard_iface *hard_iface)
{
	struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
	char *fwd_str;
	uint8_t packet_num;
	int16_t buff_pos;
	struct batman_packet *batman_packet;
	struct sk_buff *skb;

	if (hard_iface->if_status != IF_ACTIVE)
		return;

	packet_num = 0;
	buff_pos = 0;
	batman_packet = (struct batman_packet *)forw_packet->skb->data;

	/* adjust all flags and log packets */
	while (aggregated_packet(buff_pos,
				 forw_packet->packet_len,
				 batman_packet->num_tt)) {

		/* we might have aggregated direct link packets with an
		 * ordinary base packet */
		if ((forw_packet->direct_link_flags & (1 << packet_num)) &&
		    (forw_packet->if_incoming == hard_iface))
			batman_packet->flags |= DIRECTLINK;
		else
			batman_packet->flags &= ~DIRECTLINK;

		fwd_str = (packet_num > 0 ? "Forwarding" : (forw_packet->own ?
							    "Sending own" :
							    "Forwarding"));
		bat_dbg(DBG_BATMAN, bat_priv,
			"%s %spacket (originator %pM, seqno %d, TQ %d, TTL %d,"
			" IDF %s) on interface %s [%pM]\n",
			fwd_str, (packet_num > 0 ? "aggregated " : ""),
			batman_packet->orig, ntohl(batman_packet->seqno),
			batman_packet->tq, batman_packet->ttl,
			(batman_packet->flags & DIRECTLINK ?
			 "on" : "off"),
			hard_iface->net_dev->name,
			hard_iface->net_dev->dev_addr);

		buff_pos += sizeof(struct batman_packet) +
			(batman_packet->num_tt * ETH_ALEN);
		packet_num++;
		batman_packet = (struct batman_packet *)
			(forw_packet->skb->data + buff_pos);
	}

	/* create clone because function is called more than once */
	skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
	if (skb)
		send_skb_packet(skb, hard_iface, broadcast_addr);
}

/* send a batman packet */
static void send_packet(struct forw_packet *forw_packet)
{
	struct hard_iface *hard_iface;
	struct net_device *soft_iface;
	struct bat_priv *bat_priv;
	struct batman_packet *batman_packet =
		(struct batman_packet *)(forw_packet->skb->data);
	unsigned char directlink = (batman_packet->flags & DIRECTLINK ? 1 : 0);

	if (!forw_packet->if_incoming) {
		pr_err("Error - can't forward packet: incoming iface not "
		       "specified\n");
		return;
	}

	soft_iface = forw_packet->if_incoming->soft_iface;
	bat_priv = netdev_priv(soft_iface);

	if (forw_packet->if_incoming->if_status != IF_ACTIVE)
		return;

	/* multihomed peer assumed */
	/* non-primary OGMs are only broadcasted on their interface */
	if ((directlink && (batman_packet->ttl == 1)) ||
	    (forw_packet->own && (forw_packet->if_incoming->if_num > 0))) {

		/* FIXME: what about aggregated packets ? */
		bat_dbg(DBG_BATMAN, bat_priv,
			"%s packet (originator %pM, seqno %d, TTL %d) "
			"on interface %s [%pM]\n",
			(forw_packet->own ? "Sending own" : "Forwarding"),
			batman_packet->orig, ntohl(batman_packet->seqno),
			batman_packet->ttl,
			forw_packet->if_incoming->net_dev->name,
			forw_packet->if_incoming->net_dev->dev_addr);

		/* skb is only used once and than forw_packet is free'd */
		send_skb_packet(forw_packet->skb, forw_packet->if_incoming,
				broadcast_addr);
		forw_packet->skb = NULL;

		return;
	}

	/* broadcast on every interface */
	rcu_read_lock();
	list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
		if (hard_iface->soft_iface != soft_iface)
			continue;

		send_packet_to_if(forw_packet, hard_iface);
	}
	rcu_read_unlock();
}

static void rebuild_batman_packet(struct bat_priv *bat_priv,
				  struct hard_iface *hard_iface)
{
	int new_len;
	unsigned char *new_buff;
	struct batman_packet *batman_packet;

	new_len = sizeof(struct batman_packet) +
			(bat_priv->num_local_tt * ETH_ALEN);
	new_buff = kmalloc(new_len, GFP_ATOMIC);

	/* keep old buffer if kmalloc should fail */
	if (new_buff) {
		memcpy(new_buff, hard_iface->packet_buff,
		       sizeof(struct batman_packet));
		batman_packet = (struct batman_packet *)new_buff;

		batman_packet->num_tt = tt_local_fill_buffer(bat_priv,
				new_buff + sizeof(struct batman_packet),
				new_len - sizeof(struct batman_packet));

		kfree(hard_iface->packet_buff);
		hard_iface->packet_buff = new_buff;
		hard_iface->packet_len = new_len;
	}
}

void schedule_own_packet(struct hard_iface *hard_iface)
{
	struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
	struct hard_iface *primary_if;
	unsigned long send_time;
	struct batman_packet *batman_packet;
	int vis_server;

	if ((hard_iface->if_status == IF_NOT_IN_USE) ||
	    (hard_iface->if_status == IF_TO_BE_REMOVED))
		return;

	vis_server = atomic_read(&bat_priv->vis_mode);
	primary_if = primary_if_get_selected(bat_priv);

	/**
	 * the interface gets activated here to avoid race conditions between
	 * the moment of activating the interface in
	 * hardif_activate_interface() where the originator mac is set and
	 * outdated packets (especially uninitialized mac addresses) in the
	 * packet queue
	 */
	if (hard_iface->if_status == IF_TO_BE_ACTIVATED)
		hard_iface->if_status = IF_ACTIVE;

	/* if local tt has changed and interface is a primary interface */
	if ((atomic_read(&bat_priv->tt_local_changed)) &&
	    (hard_iface == primary_if))
		rebuild_batman_packet(bat_priv, hard_iface);

	/**
	 * NOTE: packet_buff might just have been re-allocated in
	 * rebuild_batman_packet()
	 */
	batman_packet = (struct batman_packet *)hard_iface->packet_buff;

	/* change sequence number to network order */
	batman_packet->seqno =
		htonl((uint32_t)atomic_read(&hard_iface->seqno));

	if (vis_server == VIS_TYPE_SERVER_SYNC)
		batman_packet->flags |= VIS_SERVER;
	else
		batman_packet->flags &= ~VIS_SERVER;

	if ((hard_iface == primary_if) &&
	    (atomic_read(&bat_priv->gw_mode) == GW_MODE_SERVER))
		batman_packet->gw_flags =
				(uint8_t)atomic_read(&bat_priv->gw_bandwidth);
	else
		batman_packet->gw_flags = 0;

	atomic_inc(&hard_iface->seqno);

	slide_own_bcast_window(hard_iface);
	send_time = own_send_time(bat_priv);
	add_bat_packet_to_list(bat_priv,
			       hard_iface->packet_buff,
			       hard_iface->packet_len,
			       hard_iface, 1, send_time);

	if (primary_if)
		hardif_free_ref(primary_if);
}

void schedule_forward_packet(struct orig_node *orig_node,
			     const struct ethhdr *ethhdr,
			     struct batman_packet *batman_packet,
			     uint8_t directlink, int tt_buff_len,
			     struct hard_iface *if_incoming)
{
	struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
	struct neigh_node *router;
	unsigned char in_tq, in_ttl, tq_avg = 0;
	unsigned long send_time;

	if (batman_packet->ttl <= 1) {
		bat_dbg(DBG_BATMAN, bat_priv, "ttl exceeded\n");
		return;
	}

	router = orig_node_get_router(orig_node);

	in_tq = batman_packet->tq;
	in_ttl = batman_packet->ttl;

	batman_packet->ttl--;
	memcpy(batman_packet->prev_sender, ethhdr->h_source, ETH_ALEN);

	/* rebroadcast tq of our best ranking neighbor to ensure the rebroadcast
	 * of our best tq value */
	if (router && router->tq_avg != 0) {

		/* rebroadcast ogm of best ranking neighbor as is */
		if (!compare_eth(router->addr, ethhdr->h_source)) {
			batman_packet->tq = router->tq_avg;

			if (router->last_ttl)
				batman_packet->ttl = router->last_ttl - 1;
		}

		tq_avg = router->tq_avg;
	}

	if (router)
		neigh_node_free_ref(router);

	/* apply hop penalty */
	batman_packet->tq = hop_penalty(batman_packet->tq, bat_priv);

	bat_dbg(DBG_BATMAN, bat_priv,
		"Forwarding packet: tq_orig: %i, tq_avg: %i, "
		"tq_forw: %i, ttl_orig: %i, ttl_forw: %i\n",
		in_tq, tq_avg, batman_packet->tq, in_ttl - 1,
		batman_packet->ttl);

	batman_packet->seqno = htonl(batman_packet->seqno);

	/* switch of primaries first hop flag when forwarding */
	batman_packet->flags &= ~PRIMARIES_FIRST_HOP;
	if (directlink)
		batman_packet->flags |= DIRECTLINK;
	else
		batman_packet->flags &= ~DIRECTLINK;

	send_time = forward_send_time();
	add_bat_packet_to_list(bat_priv,
			       (unsigned char *)batman_packet,
			       sizeof(struct batman_packet) + tt_buff_len,
			       if_incoming, 0, send_time);
}

static void forw_packet_free(struct forw_packet *forw_packet)
{
	if (forw_packet->skb)
		kfree_skb(forw_packet->skb);
	if (forw_packet->if_incoming)
		hardif_free_ref(forw_packet->if_incoming);
	kfree(forw_packet);
}

static void _add_bcast_packet_to_list(struct bat_priv *bat_priv,
				      struct forw_packet *forw_packet,
				      unsigned long send_time)
{
	INIT_HLIST_NODE(&forw_packet->list);

	/* add new packet to packet list */
	spin_lock_bh(&bat_priv->forw_bcast_list_lock);
	hlist_add_head(&forw_packet->list, &bat_priv->forw_bcast_list);
	spin_unlock_bh(&bat_priv->forw_bcast_list_lock);

	/* start timer for this packet */
	INIT_DELAYED_WORK(&forw_packet->delayed_work,
			  send_outstanding_bcast_packet);
	queue_delayed_work(bat_event_workqueue, &forw_packet->delayed_work,
			   send_time);
}

/* add a broadcast packet to the queue and setup timers. broadcast packets
 * are sent multiple times to increase probability for beeing received.
 *
 * This function returns NETDEV_TX_OK on success and NETDEV_TX_BUSY on
 * errors.
 *
 * The skb is not consumed, so the caller should make sure that the
 * skb is freed. */
int add_bcast_packet_to_list(struct bat_priv *bat_priv,
			     const struct sk_buff *skb)
{
	struct hard_iface *primary_if = NULL;
	struct forw_packet *forw_packet;
	struct bcast_packet *bcast_packet;
	struct sk_buff *newskb;

	if (!atomic_dec_not_zero(&bat_priv->bcast_queue_left)) {
		bat_dbg(DBG_BATMAN, bat_priv, "bcast packet queue full\n");
		goto out;
	}

	primary_if = primary_if_get_selected(bat_priv);
	if (!primary_if)
		goto out_and_inc;

	forw_packet = kmalloc(sizeof(struct forw_packet), GFP_ATOMIC);

	if (!forw_packet)
		goto out_and_inc;

	newskb = skb_copy(skb, GFP_ATOMIC);
	if (!newskb)
		goto packet_free;

	/* as we have a copy now, it is safe to decrease the TTL */
	bcast_packet = (struct bcast_packet *)newskb->data;
	bcast_packet->ttl--;

	skb_reset_mac_header(newskb);

	forw_packet->skb = newskb;
	forw_packet->if_incoming = primary_if;

	/* how often did we send the bcast packet ? */
	forw_packet->num_packets = 0;

	_add_bcast_packet_to_list(bat_priv, forw_packet, 1);
	return NETDEV_TX_OK;

packet_free:
	kfree(forw_packet);
out_and_inc:
	atomic_inc(&bat_priv->bcast_queue_left);
out:
	if (primary_if)
		hardif_free_ref(primary_if);
	return NETDEV_TX_BUSY;
}

static void send_outstanding_bcast_packet(struct work_struct *work)
{
	struct hard_iface *hard_iface;
	struct delayed_work *delayed_work =
		container_of(work, struct delayed_work, work);
	struct forw_packet *forw_packet =
		container_of(delayed_work, struct forw_packet, delayed_work);
	struct sk_buff *skb1;
	struct net_device *soft_iface = forw_packet->if_incoming->soft_iface;
	struct bat_priv *bat_priv = netdev_priv(soft_iface);

	spin_lock_bh(&bat_priv->forw_bcast_list_lock);
	hlist_del(&forw_packet->list);
	spin_unlock_bh(&bat_priv->forw_bcast_list_lock);

	if (atomic_read(&bat_priv->mesh_state) == MESH_DEACTIVATING)
		goto out;

	/* rebroadcast packet */
	rcu_read_lock();
	list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
		if (hard_iface->soft_iface != soft_iface)
			continue;

		/* send a copy of the saved skb */
		skb1 = skb_clone(forw_packet->skb, GFP_ATOMIC);
		if (skb1)
			send_skb_packet(skb1, hard_iface, broadcast_addr);
	}
	rcu_read_unlock();

	forw_packet->num_packets++;

	/* if we still have some more bcasts to send */
	if (forw_packet->num_packets < 3) {
		_add_bcast_packet_to_list(bat_priv, forw_packet,
					  ((5 * HZ) / 1000));
		return;
	}

out:
	forw_packet_free(forw_packet);
	atomic_inc(&bat_priv->bcast_queue_left);
}

void send_outstanding_bat_packet(struct work_struct *work)
{
	struct delayed_work *delayed_work =
		container_of(work, struct delayed_work, work);
	struct forw_packet *forw_packet =
		container_of(delayed_work, struct forw_packet, delayed_work);
	struct bat_priv *bat_priv;

	bat_priv = netdev_priv(forw_packet->if_incoming->soft_iface);
	spin_lock_bh(&bat_priv->forw_bat_list_lock);
	hlist_del(&forw_packet->list);
	spin_unlock_bh(&bat_priv->forw_bat_list_lock);

	if (atomic_read(&bat_priv->mesh_state) == MESH_DEACTIVATING)
		goto out;

	send_packet(forw_packet);

	/**
	 * we have to have at least one packet in the queue
	 * to determine the queues wake up time unless we are
	 * shutting down
	 */
	if (forw_packet->own)
		schedule_own_packet(forw_packet->if_incoming);

out:
	/* don't count own packet */
	if (!forw_packet->own)
		atomic_inc(&bat_priv->batman_queue_left);

	forw_packet_free(forw_packet);
}

void purge_outstanding_packets(struct bat_priv *bat_priv,
			       const struct hard_iface *hard_iface)
{
	struct forw_packet *forw_packet;
	struct hlist_node *tmp_node, *safe_tmp_node;
	bool pending;

	if (hard_iface)
		bat_dbg(DBG_BATMAN, bat_priv,
			"purge_outstanding_packets(): %s\n",
			hard_iface->net_dev->name);
	else
		bat_dbg(DBG_BATMAN, bat_priv,
			"purge_outstanding_packets()\n");

	/* free bcast list */
	spin_lock_bh(&bat_priv->forw_bcast_list_lock);
	hlist_for_each_entry_safe(forw_packet, tmp_node, safe_tmp_node,
				  &bat_priv->forw_bcast_list, list) {

		/**
		 * if purge_outstanding_packets() was called with an argmument
		 * we delete only packets belonging to the given interface
		 */
		if ((hard_iface) &&
		    (forw_packet->if_incoming != hard_iface))
			continue;

		spin_unlock_bh(&bat_priv->forw_bcast_list_lock);

		/**
		 * send_outstanding_bcast_packet() will lock the list to
		 * delete the item from the list
		 */
		pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
		spin_lock_bh(&bat_priv->forw_bcast_list_lock);

		if (pending) {
			hlist_del(&forw_packet->list);
			forw_packet_free(forw_packet);
		}
	}
	spin_unlock_bh(&bat_priv->forw_bcast_list_lock);

	/* free batman packet list */
	spin_lock_bh(&bat_priv->forw_bat_list_lock);
	hlist_for_each_entry_safe(forw_packet, tmp_node, safe_tmp_node,
				  &bat_priv->forw_bat_list, list) {

		/**
		 * if purge_outstanding_packets() was called with an argmument
		 * we delete only packets belonging to the given interface
		 */
		if ((hard_iface) &&
		    (forw_packet->if_incoming != hard_iface))
			continue;

		spin_unlock_bh(&bat_priv->forw_bat_list_lock);

		/**
		 * send_outstanding_bat_packet() will lock the list to
		 * delete the item from the list
		 */
		pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
		spin_lock_bh(&bat_priv->forw_bat_list_lock);

		if (pending) {
			hlist_del(&forw_packet->list);
			forw_packet_free(forw_packet);
		}
	}
	spin_unlock_bh(&bat_priv->forw_bat_list_lock);
}