xref: /linux/net/batman-adv/main.c (revision 25aee3debe0464f6c680173041fa3de30ec9ff54)
1 /* Copyright (C) 2007-2012 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, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17  * 02110-1301, USA
18  */
19 
20 #include "main.h"
21 #include "sysfs.h"
22 #include "debugfs.h"
23 #include "routing.h"
24 #include "send.h"
25 #include "originator.h"
26 #include "soft-interface.h"
27 #include "icmp_socket.h"
28 #include "translation-table.h"
29 #include "hard-interface.h"
30 #include "gateway_client.h"
31 #include "bridge_loop_avoidance.h"
32 #include "vis.h"
33 #include "hash.h"
34 #include "bat_algo.h"
35 
36 
37 /* List manipulations on hardif_list have to be rtnl_lock()'ed,
38  * list traversals just rcu-locked
39  */
40 struct list_head batadv_hardif_list;
41 static int (*batadv_rx_handler[256])(struct sk_buff *,
42 				     struct batadv_hard_iface *);
43 char batadv_routing_algo[20] = "BATMAN_IV";
44 static struct hlist_head batadv_algo_list;
45 
46 unsigned char batadv_broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
47 
48 struct workqueue_struct *batadv_event_workqueue;
49 
50 static void batadv_recv_handler_init(void);
51 
52 static int __init batadv_init(void)
53 {
54 	INIT_LIST_HEAD(&batadv_hardif_list);
55 	INIT_HLIST_HEAD(&batadv_algo_list);
56 
57 	batadv_recv_handler_init();
58 
59 	batadv_iv_init();
60 
61 	/* the name should not be longer than 10 chars - see
62 	 * http://lwn.net/Articles/23634/
63 	 */
64 	batadv_event_workqueue = create_singlethread_workqueue("bat_events");
65 
66 	if (!batadv_event_workqueue)
67 		return -ENOMEM;
68 
69 	batadv_socket_init();
70 	batadv_debugfs_init();
71 
72 	register_netdevice_notifier(&batadv_hard_if_notifier);
73 
74 	pr_info("B.A.T.M.A.N. advanced %s (compatibility version %i) loaded\n",
75 		BATADV_SOURCE_VERSION, BATADV_COMPAT_VERSION);
76 
77 	return 0;
78 }
79 
80 static void __exit batadv_exit(void)
81 {
82 	batadv_debugfs_destroy();
83 	unregister_netdevice_notifier(&batadv_hard_if_notifier);
84 	batadv_hardif_remove_interfaces();
85 
86 	flush_workqueue(batadv_event_workqueue);
87 	destroy_workqueue(batadv_event_workqueue);
88 	batadv_event_workqueue = NULL;
89 
90 	rcu_barrier();
91 }
92 
93 int batadv_mesh_init(struct net_device *soft_iface)
94 {
95 	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
96 	int ret;
97 
98 	spin_lock_init(&bat_priv->forw_bat_list_lock);
99 	spin_lock_init(&bat_priv->forw_bcast_list_lock);
100 	spin_lock_init(&bat_priv->tt_changes_list_lock);
101 	spin_lock_init(&bat_priv->tt_req_list_lock);
102 	spin_lock_init(&bat_priv->tt_roam_list_lock);
103 	spin_lock_init(&bat_priv->tt_buff_lock);
104 	spin_lock_init(&bat_priv->gw_list_lock);
105 	spin_lock_init(&bat_priv->vis_hash_lock);
106 	spin_lock_init(&bat_priv->vis_list_lock);
107 
108 	INIT_HLIST_HEAD(&bat_priv->forw_bat_list);
109 	INIT_HLIST_HEAD(&bat_priv->forw_bcast_list);
110 	INIT_HLIST_HEAD(&bat_priv->gw_list);
111 	INIT_LIST_HEAD(&bat_priv->tt_changes_list);
112 	INIT_LIST_HEAD(&bat_priv->tt_req_list);
113 	INIT_LIST_HEAD(&bat_priv->tt_roam_list);
114 
115 	ret = batadv_originator_init(bat_priv);
116 	if (ret < 0)
117 		goto err;
118 
119 	ret = batadv_tt_init(bat_priv);
120 	if (ret < 0)
121 		goto err;
122 
123 	batadv_tt_local_add(soft_iface, soft_iface->dev_addr,
124 			    BATADV_NULL_IFINDEX);
125 
126 	ret = batadv_vis_init(bat_priv);
127 	if (ret < 0)
128 		goto err;
129 
130 	ret = batadv_bla_init(bat_priv);
131 	if (ret < 0)
132 		goto err;
133 
134 	atomic_set(&bat_priv->gw_reselect, 0);
135 	atomic_set(&bat_priv->mesh_state, BATADV_MESH_ACTIVE);
136 
137 	return 0;
138 
139 err:
140 	batadv_mesh_free(soft_iface);
141 	return ret;
142 }
143 
144 void batadv_mesh_free(struct net_device *soft_iface)
145 {
146 	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
147 
148 	atomic_set(&bat_priv->mesh_state, BATADV_MESH_DEACTIVATING);
149 
150 	batadv_purge_outstanding_packets(bat_priv, NULL);
151 
152 	batadv_vis_quit(bat_priv);
153 
154 	batadv_gw_node_purge(bat_priv);
155 	batadv_originator_free(bat_priv);
156 
157 	batadv_tt_free(bat_priv);
158 
159 	batadv_bla_free(bat_priv);
160 
161 	free_percpu(bat_priv->bat_counters);
162 
163 	atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE);
164 }
165 
166 void batadv_inc_module_count(void)
167 {
168 	try_module_get(THIS_MODULE);
169 }
170 
171 void batadv_dec_module_count(void)
172 {
173 	module_put(THIS_MODULE);
174 }
175 
176 int batadv_is_my_mac(const uint8_t *addr)
177 {
178 	const struct batadv_hard_iface *hard_iface;
179 
180 	rcu_read_lock();
181 	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
182 		if (hard_iface->if_status != BATADV_IF_ACTIVE)
183 			continue;
184 
185 		if (batadv_compare_eth(hard_iface->net_dev->dev_addr, addr)) {
186 			rcu_read_unlock();
187 			return 1;
188 		}
189 	}
190 	rcu_read_unlock();
191 	return 0;
192 }
193 
194 static int batadv_recv_unhandled_packet(struct sk_buff *skb,
195 					struct batadv_hard_iface *recv_if)
196 {
197 	return NET_RX_DROP;
198 }
199 
200 /* incoming packets with the batman ethertype received on any active hard
201  * interface
202  */
203 int batadv_batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
204 			   struct packet_type *ptype,
205 			   struct net_device *orig_dev)
206 {
207 	struct batadv_priv *bat_priv;
208 	struct batadv_ogm_packet *batadv_ogm_packet;
209 	struct batadv_hard_iface *hard_iface;
210 	uint8_t idx;
211 	int ret;
212 
213 	hard_iface = container_of(ptype, struct batadv_hard_iface,
214 				  batman_adv_ptype);
215 	skb = skb_share_check(skb, GFP_ATOMIC);
216 
217 	/* skb was released by skb_share_check() */
218 	if (!skb)
219 		goto err_out;
220 
221 	/* packet should hold at least type and version */
222 	if (unlikely(!pskb_may_pull(skb, 2)))
223 		goto err_free;
224 
225 	/* expect a valid ethernet header here. */
226 	if (unlikely(skb->mac_len != ETH_HLEN || !skb_mac_header(skb)))
227 		goto err_free;
228 
229 	if (!hard_iface->soft_iface)
230 		goto err_free;
231 
232 	bat_priv = netdev_priv(hard_iface->soft_iface);
233 
234 	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
235 		goto err_free;
236 
237 	/* discard frames on not active interfaces */
238 	if (hard_iface->if_status != BATADV_IF_ACTIVE)
239 		goto err_free;
240 
241 	batadv_ogm_packet = (struct batadv_ogm_packet *)skb->data;
242 
243 	if (batadv_ogm_packet->header.version != BATADV_COMPAT_VERSION) {
244 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
245 			   "Drop packet: incompatible batman version (%i)\n",
246 			   batadv_ogm_packet->header.version);
247 		goto err_free;
248 	}
249 
250 	/* all receive handlers return whether they received or reused
251 	 * the supplied skb. if not, we have to free the skb.
252 	 */
253 	idx = batadv_ogm_packet->header.packet_type;
254 	ret = (*batadv_rx_handler[idx])(skb, hard_iface);
255 
256 	if (ret == NET_RX_DROP)
257 		kfree_skb(skb);
258 
259 	/* return NET_RX_SUCCESS in any case as we
260 	 * most probably dropped the packet for
261 	 * routing-logical reasons.
262 	 */
263 	return NET_RX_SUCCESS;
264 
265 err_free:
266 	kfree_skb(skb);
267 err_out:
268 	return NET_RX_DROP;
269 }
270 
271 static void batadv_recv_handler_init(void)
272 {
273 	int i;
274 
275 	for (i = 0; i < ARRAY_SIZE(batadv_rx_handler); i++)
276 		batadv_rx_handler[i] = batadv_recv_unhandled_packet;
277 
278 	/* batman icmp packet */
279 	batadv_rx_handler[BATADV_ICMP] = batadv_recv_icmp_packet;
280 	/* unicast packet */
281 	batadv_rx_handler[BATADV_UNICAST] = batadv_recv_unicast_packet;
282 	/* fragmented unicast packet */
283 	batadv_rx_handler[BATADV_UNICAST_FRAG] = batadv_recv_ucast_frag_packet;
284 	/* broadcast packet */
285 	batadv_rx_handler[BATADV_BCAST] = batadv_recv_bcast_packet;
286 	/* vis packet */
287 	batadv_rx_handler[BATADV_VIS] = batadv_recv_vis_packet;
288 	/* Translation table query (request or response) */
289 	batadv_rx_handler[BATADV_TT_QUERY] = batadv_recv_tt_query;
290 	/* Roaming advertisement */
291 	batadv_rx_handler[BATADV_ROAM_ADV] = batadv_recv_roam_adv;
292 }
293 
294 int
295 batadv_recv_handler_register(uint8_t packet_type,
296 			     int (*recv_handler)(struct sk_buff *,
297 						 struct batadv_hard_iface *))
298 {
299 	if (batadv_rx_handler[packet_type] != &batadv_recv_unhandled_packet)
300 		return -EBUSY;
301 
302 	batadv_rx_handler[packet_type] = recv_handler;
303 	return 0;
304 }
305 
306 void batadv_recv_handler_unregister(uint8_t packet_type)
307 {
308 	batadv_rx_handler[packet_type] = batadv_recv_unhandled_packet;
309 }
310 
311 static struct batadv_algo_ops *batadv_algo_get(char *name)
312 {
313 	struct batadv_algo_ops *bat_algo_ops = NULL, *bat_algo_ops_tmp;
314 	struct hlist_node *node;
315 
316 	hlist_for_each_entry(bat_algo_ops_tmp, node, &batadv_algo_list, list) {
317 		if (strcmp(bat_algo_ops_tmp->name, name) != 0)
318 			continue;
319 
320 		bat_algo_ops = bat_algo_ops_tmp;
321 		break;
322 	}
323 
324 	return bat_algo_ops;
325 }
326 
327 int batadv_algo_register(struct batadv_algo_ops *bat_algo_ops)
328 {
329 	struct batadv_algo_ops *bat_algo_ops_tmp;
330 	int ret;
331 
332 	bat_algo_ops_tmp = batadv_algo_get(bat_algo_ops->name);
333 	if (bat_algo_ops_tmp) {
334 		pr_info("Trying to register already registered routing algorithm: %s\n",
335 			bat_algo_ops->name);
336 		ret = -EEXIST;
337 		goto out;
338 	}
339 
340 	/* all algorithms must implement all ops (for now) */
341 	if (!bat_algo_ops->bat_iface_enable ||
342 	    !bat_algo_ops->bat_iface_disable ||
343 	    !bat_algo_ops->bat_iface_update_mac ||
344 	    !bat_algo_ops->bat_primary_iface_set ||
345 	    !bat_algo_ops->bat_ogm_schedule ||
346 	    !bat_algo_ops->bat_ogm_emit) {
347 		pr_info("Routing algo '%s' does not implement required ops\n",
348 			bat_algo_ops->name);
349 		ret = -EINVAL;
350 		goto out;
351 	}
352 
353 	INIT_HLIST_NODE(&bat_algo_ops->list);
354 	hlist_add_head(&bat_algo_ops->list, &batadv_algo_list);
355 	ret = 0;
356 
357 out:
358 	return ret;
359 }
360 
361 int batadv_algo_select(struct batadv_priv *bat_priv, char *name)
362 {
363 	struct batadv_algo_ops *bat_algo_ops;
364 	int ret = -EINVAL;
365 
366 	bat_algo_ops = batadv_algo_get(name);
367 	if (!bat_algo_ops)
368 		goto out;
369 
370 	bat_priv->bat_algo_ops = bat_algo_ops;
371 	ret = 0;
372 
373 out:
374 	return ret;
375 }
376 
377 int batadv_algo_seq_print_text(struct seq_file *seq, void *offset)
378 {
379 	struct batadv_algo_ops *bat_algo_ops;
380 	struct hlist_node *node;
381 
382 	seq_printf(seq, "Available routing algorithms:\n");
383 
384 	hlist_for_each_entry(bat_algo_ops, node, &batadv_algo_list, list) {
385 		seq_printf(seq, "%s\n", bat_algo_ops->name);
386 	}
387 
388 	return 0;
389 }
390 
391 static int batadv_param_set_ra(const char *val, const struct kernel_param *kp)
392 {
393 	struct batadv_algo_ops *bat_algo_ops;
394 	char *algo_name = (char *)val;
395 	size_t name_len = strlen(algo_name);
396 
397 	if (algo_name[name_len - 1] == '\n')
398 		algo_name[name_len - 1] = '\0';
399 
400 	bat_algo_ops = batadv_algo_get(algo_name);
401 	if (!bat_algo_ops) {
402 		pr_err("Routing algorithm '%s' is not supported\n", algo_name);
403 		return -EINVAL;
404 	}
405 
406 	return param_set_copystring(algo_name, kp);
407 }
408 
409 static const struct kernel_param_ops batadv_param_ops_ra = {
410 	.set = batadv_param_set_ra,
411 	.get = param_get_string,
412 };
413 
414 static struct kparam_string batadv_param_string_ra = {
415 	.maxlen = sizeof(batadv_routing_algo),
416 	.string = batadv_routing_algo,
417 };
418 
419 module_param_cb(routing_algo, &batadv_param_ops_ra, &batadv_param_string_ra,
420 		0644);
421 module_init(batadv_init);
422 module_exit(batadv_exit);
423 
424 MODULE_LICENSE("GPL");
425 
426 MODULE_AUTHOR(BATADV_DRIVER_AUTHOR);
427 MODULE_DESCRIPTION(BATADV_DRIVER_DESC);
428 MODULE_SUPPORTED_DEVICE(BATADV_DRIVER_DEVICE);
429 MODULE_VERSION(BATADV_SOURCE_VERSION);
430