summaryrefslogtreecommitdiffstats
path: root/net/batman-adv/main.c
blob: 3e30a0f1b908b2872bcb6a13100306e0deda0c85 (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
/* Copyright (C) 2007-2013 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 <linux/crc32c.h>
#include <linux/highmem.h>
#include "main.h"
#include "sysfs.h"
#include "debugfs.h"
#include "routing.h"
#include "send.h"
#include "originator.h"
#include "soft-interface.h"
#include "icmp_socket.h"
#include "translation-table.h"
#include "hard-interface.h"
#include "gateway_client.h"
#include "bridge_loop_avoidance.h"
#include "distributed-arp-table.h"
#include "vis.h"
#include "hash.h"
#include "bat_algo.h"
#include "network-coding.h"


/* List manipulations on hardif_list have to be rtnl_lock()'ed,
 * list traversals just rcu-locked
 */
struct list_head batadv_hardif_list;
static int (*batadv_rx_handler[256])(struct sk_buff *,
				     struct batadv_hard_iface *);
char batadv_routing_algo[20] = "BATMAN_IV";
static struct hlist_head batadv_algo_list;

unsigned char batadv_broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};

struct workqueue_struct *batadv_event_workqueue;

static void batadv_recv_handler_init(void);

static int __init batadv_init(void)
{
	INIT_LIST_HEAD(&batadv_hardif_list);
	INIT_HLIST_HEAD(&batadv_algo_list);

	batadv_recv_handler_init();

	batadv_iv_init();

	batadv_event_workqueue = create_singlethread_workqueue("bat_events");

	if (!batadv_event_workqueue)
		return -ENOMEM;

	batadv_socket_init();
	batadv_debugfs_init();

	register_netdevice_notifier(&batadv_hard_if_notifier);
	rtnl_link_register(&batadv_link_ops);

	pr_info("B.A.T.M.A.N. advanced %s (compatibility version %i) loaded\n",
		BATADV_SOURCE_VERSION, BATADV_COMPAT_VERSION);

	return 0;
}

static void __exit batadv_exit(void)
{
	batadv_debugfs_destroy();
	rtnl_link_unregister(&batadv_link_ops);
	unregister_netdevice_notifier(&batadv_hard_if_notifier);
	batadv_hardif_remove_interfaces();

	flush_workqueue(batadv_event_workqueue);
	destroy_workqueue(batadv_event_workqueue);
	batadv_event_workqueue = NULL;

	rcu_barrier();
}

int batadv_mesh_init(struct net_device *soft_iface)
{
	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
	int ret;

	spin_lock_init(&bat_priv->forw_bat_list_lock);
	spin_lock_init(&bat_priv->forw_bcast_list_lock);
	spin_lock_init(&bat_priv->tt.changes_list_lock);
	spin_lock_init(&bat_priv->tt.req_list_lock);
	spin_lock_init(&bat_priv->tt.roam_list_lock);
	spin_lock_init(&bat_priv->tt.last_changeset_lock);
	spin_lock_init(&bat_priv->gw.list_lock);
	spin_lock_init(&bat_priv->vis.hash_lock);
	spin_lock_init(&bat_priv->vis.list_lock);

	INIT_HLIST_HEAD(&bat_priv->forw_bat_list);
	INIT_HLIST_HEAD(&bat_priv->forw_bcast_list);
	INIT_HLIST_HEAD(&bat_priv->gw.list);
	INIT_LIST_HEAD(&bat_priv->tt.changes_list);
	INIT_LIST_HEAD(&bat_priv->tt.req_list);
	INIT_LIST_HEAD(&bat_priv->tt.roam_list);

	ret = batadv_originator_init(bat_priv);
	if (ret < 0)
		goto err;

	ret = batadv_tt_init(bat_priv);
	if (ret < 0)
		goto err;

	batadv_tt_local_add(soft_iface, soft_iface->dev_addr,
			    BATADV_NULL_IFINDEX);

	ret = batadv_vis_init(bat_priv);
	if (ret < 0)
		goto err;

	ret = batadv_bla_init(bat_priv);
	if (ret < 0)
		goto err;

	ret = batadv_dat_init(bat_priv);
	if (ret < 0)
		goto err;

	ret = batadv_nc_init(bat_priv);
	if (ret < 0)
		goto err;

	atomic_set(&bat_priv->gw.reselect, 0);
	atomic_set(&bat_priv->mesh_state, BATADV_MESH_ACTIVE);

	return 0;

err:
	batadv_mesh_free(soft_iface);
	return ret;
}

void batadv_mesh_free(struct net_device *soft_iface)
{
	struct batadv_priv *bat_priv = netdev_priv(soft_iface);

	atomic_set(&bat_priv->mesh_state, BATADV_MESH_DEACTIVATING);

	batadv_purge_outstanding_packets(bat_priv, NULL);

	batadv_vis_quit(bat_priv);

	batadv_gw_node_purge(bat_priv);
	batadv_originator_free(bat_priv);
	batadv_nc_free(bat_priv);

	batadv_tt_free(bat_priv);

	batadv_bla_free(bat_priv);

	batadv_dat_free(bat_priv);

	free_percpu(bat_priv->bat_counters);

	atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE);
}

/**
 * batadv_is_my_mac - check if the given mac address belongs to any of the real
 * interfaces in the current mesh
 * @bat_priv: the bat priv with all the soft interface information
 * @addr: the address to check
 */
int batadv_is_my_mac(struct batadv_priv *bat_priv, const uint8_t *addr)
{
	const struct batadv_hard_iface *hard_iface;

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

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

		if (batadv_compare_eth(hard_iface->net_dev->dev_addr, addr)) {
			rcu_read_unlock();
			return 1;
		}
	}
	rcu_read_unlock();
	return 0;
}

/**
 * batadv_seq_print_text_primary_if_get - called from debugfs table printing
 *  function that requires the primary interface
 * @seq: debugfs table seq_file struct
 *
 * Returns primary interface if found or NULL otherwise.
 */
struct batadv_hard_iface *
batadv_seq_print_text_primary_if_get(struct seq_file *seq)
{
	struct net_device *net_dev = (struct net_device *)seq->private;
	struct batadv_priv *bat_priv = netdev_priv(net_dev);
	struct batadv_hard_iface *primary_if;

	primary_if = batadv_primary_if_get_selected(bat_priv);

	if (!primary_if) {
		seq_printf(seq,
			   "BATMAN mesh %s disabled - please specify interfaces to enable it\n",
			   net_dev->name);
		goto out;
	}

	if (primary_if->if_status == BATADV_IF_ACTIVE)
		goto out;

	seq_printf(seq,
		   "BATMAN mesh %s disabled - primary interface not active\n",
		   net_dev->name);
	batadv_hardif_free_ref(primary_if);
	primary_if = NULL;

out:
	return primary_if;
}

static int batadv_recv_unhandled_packet(struct sk_buff *skb,
					struct batadv_hard_iface *recv_if)
{
	return NET_RX_DROP;
}

/* incoming packets with the batman ethertype received on any active hard
 * interface
 */
int batadv_batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
			   struct packet_type *ptype,
			   struct net_device *orig_dev)
{
	struct batadv_priv *bat_priv;
	struct batadv_ogm_packet *batadv_ogm_packet;
	struct batadv_hard_iface *hard_iface;
	uint8_t idx;
	int ret;

	hard_iface = container_of(ptype, struct batadv_hard_iface,
				  batman_adv_ptype);
	skb = skb_share_check(skb, GFP_ATOMIC);

	/* skb was released by skb_share_check() */
	if (!skb)
		goto err_out;

	/* packet should hold at least type and version */
	if (unlikely(!pskb_may_pull(skb, 2)))
		goto err_free;

	/* expect a valid ethernet header here. */
	if (unlikely(skb->mac_len != ETH_HLEN || !skb_mac_header(skb)))
		goto err_free;

	if (!hard_iface->soft_iface)
		goto err_free;

	bat_priv = netdev_priv(hard_iface->soft_iface);

	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
		goto err_free;

	/* discard frames on not active interfaces */
	if (hard_iface->if_status != BATADV_IF_ACTIVE)
		goto err_free;

	batadv_ogm_packet = (struct batadv_ogm_packet *)skb->data;

	if (batadv_ogm_packet->header.version != BATADV_COMPAT_VERSION) {
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Drop packet: incompatible batman version (%i)\n",
			   batadv_ogm_packet->header.version);
		goto err_free;
	}

	/* all receive handlers return whether they received or reused
	 * the supplied skb. if not, we have to free the skb.
	 */
	idx = batadv_ogm_packet->header.packet_type;
	ret = (*batadv_rx_handler[idx])(skb, hard_iface);

	if (ret == NET_RX_DROP)
		kfree_skb(skb);

	/* return NET_RX_SUCCESS in any case as we
	 * most probably dropped the packet for
	 * routing-logical reasons.
	 */
	return NET_RX_SUCCESS;

err_free:
	kfree_skb(skb);
err_out:
	return NET_RX_DROP;
}

static void batadv_recv_handler_init(void)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(batadv_rx_handler); i++)
		batadv_rx_handler[i] = batadv_recv_unhandled_packet;

	/* batman icmp packet */
	batadv_rx_handler[BATADV_ICMP] = batadv_recv_icmp_packet;
	/* unicast with 4 addresses packet */
	batadv_rx_handler[BATADV_UNICAST_4ADDR] = batadv_recv_unicast_packet;
	/* unicast packet */
	batadv_rx_handler[BATADV_UNICAST] = batadv_recv_unicast_packet;
	/* fragmented unicast packet */
	batadv_rx_handler[BATADV_UNICAST_FRAG] = batadv_recv_ucast_frag_packet;
	/* broadcast packet */
	batadv_rx_handler[BATADV_BCAST] = batadv_recv_bcast_packet;
	/* vis packet */
	batadv_rx_handler[BATADV_VIS] = batadv_recv_vis_packet;
	/* Translation table query (request or response) */
	batadv_rx_handler[BATADV_TT_QUERY] = batadv_recv_tt_query;
	/* Roaming advertisement */
	batadv_rx_handler[BATADV_ROAM_ADV] = batadv_recv_roam_adv;
}

int
batadv_recv_handler_register(uint8_t packet_type,
			     int (*recv_handler)(struct sk_buff *,
						 struct batadv_hard_iface *))
{
	if (batadv_rx_handler[packet_type] != &batadv_recv_unhandled_packet)
		return -EBUSY;

	batadv_rx_handler[packet_type] = recv_handler;
	return 0;
}

void batadv_recv_handler_unregister(uint8_t packet_type)
{
	batadv_rx_handler[packet_type] = batadv_recv_unhandled_packet;
}

static struct batadv_algo_ops *batadv_algo_get(char *name)
{
	struct batadv_algo_ops *bat_algo_ops = NULL, *bat_algo_ops_tmp;

	hlist_for_each_entry(bat_algo_ops_tmp, &batadv_algo_list, list) {
		if (strcmp(bat_algo_ops_tmp->name, name) != 0)
			continue;

		bat_algo_ops = bat_algo_ops_tmp;
		break;
	}

	return bat_algo_ops;
}

int batadv_algo_register(struct batadv_algo_ops *bat_algo_ops)
{
	struct batadv_algo_ops *bat_algo_ops_tmp;
	int ret;

	bat_algo_ops_tmp = batadv_algo_get(bat_algo_ops->name);
	if (bat_algo_ops_tmp) {
		pr_info("Trying to register already registered routing algorithm: %s\n",
			bat_algo_ops->name);
		ret = -EEXIST;
		goto out;
	}

	/* all algorithms must implement all ops (for now) */
	if (!bat_algo_ops->bat_iface_enable ||
	    !bat_algo_ops->bat_iface_disable ||
	    !bat_algo_ops->bat_iface_update_mac ||
	    !bat_algo_ops->bat_primary_iface_set ||
	    !bat_algo_ops->bat_ogm_schedule ||
	    !bat_algo_ops->bat_ogm_emit) {
		pr_info("Routing algo '%s' does not implement required ops\n",
			bat_algo_ops->name);
		ret = -EINVAL;
		goto out;
	}

	INIT_HLIST_NODE(&bat_algo_ops->list);
	hlist_add_head(&bat_algo_ops->list, &batadv_algo_list);
	ret = 0;

out:
	return ret;
}

int batadv_algo_select(struct batadv_priv *bat_priv, char *name)
{
	struct batadv_algo_ops *bat_algo_ops;
	int ret = -EINVAL;

	bat_algo_ops = batadv_algo_get(name);
	if (!bat_algo_ops)
		goto out;

	bat_priv->bat_algo_ops = bat_algo_ops;
	ret = 0;

out:
	return ret;
}

int batadv_algo_seq_print_text(struct seq_file *seq, void *offset)
{
	struct batadv_algo_ops *bat_algo_ops;

	seq_puts(seq, "Available routing algorithms:\n");

	hlist_for_each_entry(bat_algo_ops, &batadv_algo_list, list) {
		seq_printf(seq, "%s\n", bat_algo_ops->name);
	}

	return 0;
}

/**
 * batadv_skb_crc32 - calculate CRC32 of the whole packet and skip bytes in
 *  the header
 * @skb: skb pointing to fragmented socket buffers
 * @payload_ptr: Pointer to position inside the head buffer of the skb
 *  marking the start of the data to be CRC'ed
 *
 * payload_ptr must always point to an address in the skb head buffer and not to
 * a fragment.
 */
__be32 batadv_skb_crc32(struct sk_buff *skb, u8 *payload_ptr)
{
	u32 crc = 0;
	unsigned int from;
	unsigned int to = skb->len;
	struct skb_seq_state st;
	const u8 *data;
	unsigned int len;
	unsigned int consumed = 0;

	from = (unsigned int)(payload_ptr - skb->data);

	skb_prepare_seq_read(skb, from, to, &st);
	while ((len = skb_seq_read(consumed, &data, &st)) != 0) {
		crc = crc32c(crc, data, len);
		consumed += len;
	}
	skb_abort_seq_read(&st);

	return htonl(crc);
}

static int batadv_param_set_ra(const char *val, const struct kernel_param *kp)
{
	struct batadv_algo_ops *bat_algo_ops;
	char *algo_name = (char *)val;
	size_t name_len = strlen(algo_name);

	if (algo_name[name_len - 1] == '\n')
		algo_name[name_len - 1] = '\0';

	bat_algo_ops = batadv_algo_get(algo_name);
	if (!bat_algo_ops) {
		pr_err("Routing algorithm '%s' is not supported\n", algo_name);
		return -EINVAL;
	}

	return param_set_copystring(algo_name, kp);
}

static const struct kernel_param_ops batadv_param_ops_ra = {
	.set = batadv_param_set_ra,
	.get = param_get_string,
};

static struct kparam_string batadv_param_string_ra = {
	.maxlen = sizeof(batadv_routing_algo),
	.string = batadv_routing_algo,
};

module_param_cb(routing_algo, &batadv_param_ops_ra, &batadv_param_string_ra,
		0644);
module_init(batadv_init);
module_exit(batadv_exit);

MODULE_LICENSE("GPL");

MODULE_AUTHOR(BATADV_DRIVER_AUTHOR);
MODULE_DESCRIPTION(BATADV_DRIVER_DESC);
MODULE_SUPPORTED_DEVICE(BATADV_DRIVER_DEVICE);
MODULE_VERSION(BATADV_SOURCE_VERSION);
OpenPOWER on IntegriCloud