xref: /linux/net/batman-adv/main.c (revision 26b0d14106954ae46d2f4f7eec3481828a210f7d)
1 /*
2  * Copyright (C) 2007-2012 B.A.T.M.A.N. contributors:
3  *
4  * Marek Lindner, Simon Wunderlich
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of version 2 of the GNU General Public
8  * License as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  * General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
18  * 02110-1301, USA
19  *
20  */
21 
22 #include "main.h"
23 #include "bat_sysfs.h"
24 #include "bat_debugfs.h"
25 #include "routing.h"
26 #include "send.h"
27 #include "originator.h"
28 #include "soft-interface.h"
29 #include "icmp_socket.h"
30 #include "translation-table.h"
31 #include "hard-interface.h"
32 #include "gateway_client.h"
33 #include "bridge_loop_avoidance.h"
34 #include "vis.h"
35 #include "hash.h"
36 #include "bat_algo.h"
37 
38 
39 /* List manipulations on hardif_list have to be rtnl_lock()'ed,
40  * list traversals just rcu-locked */
41 struct list_head hardif_list;
42 static int (*recv_packet_handler[256])(struct sk_buff *, struct hard_iface *);
43 char bat_routing_algo[20] = "BATMAN IV";
44 static struct hlist_head bat_algo_list;
45 
46 unsigned char broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
47 
48 struct workqueue_struct *bat_event_workqueue;
49 
50 static void recv_handler_init(void);
51 
52 static int __init batman_init(void)
53 {
54 	INIT_LIST_HEAD(&hardif_list);
55 	INIT_HLIST_HEAD(&bat_algo_list);
56 
57 	recv_handler_init();
58 
59 	bat_iv_init();
60 
61 	/* the name should not be longer than 10 chars - see
62 	 * http://lwn.net/Articles/23634/ */
63 	bat_event_workqueue = create_singlethread_workqueue("bat_events");
64 
65 	if (!bat_event_workqueue)
66 		return -ENOMEM;
67 
68 	bat_socket_init();
69 	debugfs_init();
70 
71 	register_netdevice_notifier(&hard_if_notifier);
72 
73 	pr_info("B.A.T.M.A.N. advanced %s (compatibility version %i) loaded\n",
74 		SOURCE_VERSION, COMPAT_VERSION);
75 
76 	return 0;
77 }
78 
79 static void __exit batman_exit(void)
80 {
81 	debugfs_destroy();
82 	unregister_netdevice_notifier(&hard_if_notifier);
83 	hardif_remove_interfaces();
84 
85 	flush_workqueue(bat_event_workqueue);
86 	destroy_workqueue(bat_event_workqueue);
87 	bat_event_workqueue = NULL;
88 
89 	rcu_barrier();
90 }
91 
92 int mesh_init(struct net_device *soft_iface)
93 {
94 	struct bat_priv *bat_priv = netdev_priv(soft_iface);
95 
96 	spin_lock_init(&bat_priv->forw_bat_list_lock);
97 	spin_lock_init(&bat_priv->forw_bcast_list_lock);
98 	spin_lock_init(&bat_priv->tt_changes_list_lock);
99 	spin_lock_init(&bat_priv->tt_req_list_lock);
100 	spin_lock_init(&bat_priv->tt_roam_list_lock);
101 	spin_lock_init(&bat_priv->tt_buff_lock);
102 	spin_lock_init(&bat_priv->gw_list_lock);
103 	spin_lock_init(&bat_priv->vis_hash_lock);
104 	spin_lock_init(&bat_priv->vis_list_lock);
105 
106 	INIT_HLIST_HEAD(&bat_priv->forw_bat_list);
107 	INIT_HLIST_HEAD(&bat_priv->forw_bcast_list);
108 	INIT_HLIST_HEAD(&bat_priv->gw_list);
109 	INIT_LIST_HEAD(&bat_priv->tt_changes_list);
110 	INIT_LIST_HEAD(&bat_priv->tt_req_list);
111 	INIT_LIST_HEAD(&bat_priv->tt_roam_list);
112 
113 	if (originator_init(bat_priv) < 1)
114 		goto err;
115 
116 	if (tt_init(bat_priv) < 1)
117 		goto err;
118 
119 	tt_local_add(soft_iface, soft_iface->dev_addr, NULL_IFINDEX);
120 
121 	if (vis_init(bat_priv) < 1)
122 		goto err;
123 
124 	if (bla_init(bat_priv) < 1)
125 		goto err;
126 
127 	atomic_set(&bat_priv->gw_reselect, 0);
128 	atomic_set(&bat_priv->mesh_state, MESH_ACTIVE);
129 	goto end;
130 
131 err:
132 	mesh_free(soft_iface);
133 	return -1;
134 
135 end:
136 	return 0;
137 }
138 
139 void mesh_free(struct net_device *soft_iface)
140 {
141 	struct bat_priv *bat_priv = netdev_priv(soft_iface);
142 
143 	atomic_set(&bat_priv->mesh_state, MESH_DEACTIVATING);
144 
145 	purge_outstanding_packets(bat_priv, NULL);
146 
147 	vis_quit(bat_priv);
148 
149 	gw_node_purge(bat_priv);
150 	originator_free(bat_priv);
151 
152 	tt_free(bat_priv);
153 
154 	bla_free(bat_priv);
155 
156 	atomic_set(&bat_priv->mesh_state, MESH_INACTIVE);
157 }
158 
159 void inc_module_count(void)
160 {
161 	try_module_get(THIS_MODULE);
162 }
163 
164 void dec_module_count(void)
165 {
166 	module_put(THIS_MODULE);
167 }
168 
169 int is_my_mac(const uint8_t *addr)
170 {
171 	const struct hard_iface *hard_iface;
172 
173 	rcu_read_lock();
174 	list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
175 		if (hard_iface->if_status != IF_ACTIVE)
176 			continue;
177 
178 		if (compare_eth(hard_iface->net_dev->dev_addr, addr)) {
179 			rcu_read_unlock();
180 			return 1;
181 		}
182 	}
183 	rcu_read_unlock();
184 	return 0;
185 }
186 
187 static int recv_unhandled_packet(struct sk_buff *skb,
188 				 struct hard_iface *recv_if)
189 {
190 	return NET_RX_DROP;
191 }
192 
193 /* incoming packets with the batman ethertype received on any active hard
194  * interface
195  */
196 int batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
197 		    struct packet_type *ptype, struct net_device *orig_dev)
198 {
199 	struct bat_priv *bat_priv;
200 	struct batman_ogm_packet *batman_ogm_packet;
201 	struct hard_iface *hard_iface;
202 	uint8_t idx;
203 	int ret;
204 
205 	hard_iface = container_of(ptype, struct hard_iface, batman_adv_ptype);
206 	skb = skb_share_check(skb, GFP_ATOMIC);
207 
208 	/* skb was released by skb_share_check() */
209 	if (!skb)
210 		goto err_out;
211 
212 	/* packet should hold at least type and version */
213 	if (unlikely(!pskb_may_pull(skb, 2)))
214 		goto err_free;
215 
216 	/* expect a valid ethernet header here. */
217 	if (unlikely(skb->mac_len != ETH_HLEN || !skb_mac_header(skb)))
218 		goto err_free;
219 
220 	if (!hard_iface->soft_iface)
221 		goto err_free;
222 
223 	bat_priv = netdev_priv(hard_iface->soft_iface);
224 
225 	if (atomic_read(&bat_priv->mesh_state) != MESH_ACTIVE)
226 		goto err_free;
227 
228 	/* discard frames on not active interfaces */
229 	if (hard_iface->if_status != IF_ACTIVE)
230 		goto err_free;
231 
232 	batman_ogm_packet = (struct batman_ogm_packet *)skb->data;
233 
234 	if (batman_ogm_packet->header.version != COMPAT_VERSION) {
235 		bat_dbg(DBG_BATMAN, bat_priv,
236 			"Drop packet: incompatible batman version (%i)\n",
237 			batman_ogm_packet->header.version);
238 		goto err_free;
239 	}
240 
241 	/* all receive handlers return whether they received or reused
242 	 * the supplied skb. if not, we have to free the skb.
243 	 */
244 	idx = batman_ogm_packet->header.packet_type;
245 	ret = (*recv_packet_handler[idx])(skb, hard_iface);
246 
247 	if (ret == NET_RX_DROP)
248 		kfree_skb(skb);
249 
250 	/* return NET_RX_SUCCESS in any case as we
251 	 * most probably dropped the packet for
252 	 * routing-logical reasons.
253 	 */
254 	return NET_RX_SUCCESS;
255 
256 err_free:
257 	kfree_skb(skb);
258 err_out:
259 	return NET_RX_DROP;
260 }
261 
262 static void recv_handler_init(void)
263 {
264 	int i;
265 
266 	for (i = 0; i < ARRAY_SIZE(recv_packet_handler); i++)
267 		recv_packet_handler[i] = recv_unhandled_packet;
268 
269 	/* batman icmp packet */
270 	recv_packet_handler[BAT_ICMP] = recv_icmp_packet;
271 	/* unicast packet */
272 	recv_packet_handler[BAT_UNICAST] = recv_unicast_packet;
273 	/* fragmented unicast packet */
274 	recv_packet_handler[BAT_UNICAST_FRAG] = recv_ucast_frag_packet;
275 	/* broadcast packet */
276 	recv_packet_handler[BAT_BCAST] = recv_bcast_packet;
277 	/* vis packet */
278 	recv_packet_handler[BAT_VIS] = recv_vis_packet;
279 	/* Translation table query (request or response) */
280 	recv_packet_handler[BAT_TT_QUERY] = recv_tt_query;
281 	/* Roaming advertisement */
282 	recv_packet_handler[BAT_ROAM_ADV] = recv_roam_adv;
283 }
284 
285 int recv_handler_register(uint8_t packet_type,
286 			  int (*recv_handler)(struct sk_buff *,
287 					      struct hard_iface *))
288 {
289 	if (recv_packet_handler[packet_type] != &recv_unhandled_packet)
290 		return -EBUSY;
291 
292 	recv_packet_handler[packet_type] = recv_handler;
293 	return 0;
294 }
295 
296 void recv_handler_unregister(uint8_t packet_type)
297 {
298 	recv_packet_handler[packet_type] = recv_unhandled_packet;
299 }
300 
301 static struct bat_algo_ops *bat_algo_get(char *name)
302 {
303 	struct bat_algo_ops *bat_algo_ops = NULL, *bat_algo_ops_tmp;
304 	struct hlist_node *node;
305 
306 	hlist_for_each_entry(bat_algo_ops_tmp, node, &bat_algo_list, list) {
307 		if (strcmp(bat_algo_ops_tmp->name, name) != 0)
308 			continue;
309 
310 		bat_algo_ops = bat_algo_ops_tmp;
311 		break;
312 	}
313 
314 	return bat_algo_ops;
315 }
316 
317 int bat_algo_register(struct bat_algo_ops *bat_algo_ops)
318 {
319 	struct bat_algo_ops *bat_algo_ops_tmp;
320 	int ret = -1;
321 
322 	bat_algo_ops_tmp = bat_algo_get(bat_algo_ops->name);
323 	if (bat_algo_ops_tmp) {
324 		pr_info("Trying to register already registered routing algorithm: %s\n",
325 			bat_algo_ops->name);
326 		goto out;
327 	}
328 
329 	/* all algorithms must implement all ops (for now) */
330 	if (!bat_algo_ops->bat_iface_enable ||
331 	    !bat_algo_ops->bat_iface_disable ||
332 	    !bat_algo_ops->bat_iface_update_mac ||
333 	    !bat_algo_ops->bat_primary_iface_set ||
334 	    !bat_algo_ops->bat_ogm_schedule ||
335 	    !bat_algo_ops->bat_ogm_emit) {
336 		pr_info("Routing algo '%s' does not implement required ops\n",
337 			bat_algo_ops->name);
338 		goto out;
339 	}
340 
341 	INIT_HLIST_NODE(&bat_algo_ops->list);
342 	hlist_add_head(&bat_algo_ops->list, &bat_algo_list);
343 	ret = 0;
344 
345 out:
346 	return ret;
347 }
348 
349 int bat_algo_select(struct bat_priv *bat_priv, char *name)
350 {
351 	struct bat_algo_ops *bat_algo_ops;
352 	int ret = -1;
353 
354 	bat_algo_ops = bat_algo_get(name);
355 	if (!bat_algo_ops)
356 		goto out;
357 
358 	bat_priv->bat_algo_ops = bat_algo_ops;
359 	ret = 0;
360 
361 out:
362 	return ret;
363 }
364 
365 int bat_algo_seq_print_text(struct seq_file *seq, void *offset)
366 {
367 	struct bat_algo_ops *bat_algo_ops;
368 	struct hlist_node *node;
369 
370 	seq_printf(seq, "Available routing algorithms:\n");
371 
372 	hlist_for_each_entry(bat_algo_ops, node, &bat_algo_list, list) {
373 		seq_printf(seq, "%s\n", bat_algo_ops->name);
374 	}
375 
376 	return 0;
377 }
378 
379 static int param_set_ra(const char *val, const struct kernel_param *kp)
380 {
381 	struct bat_algo_ops *bat_algo_ops;
382 
383 	bat_algo_ops = bat_algo_get((char *)val);
384 	if (!bat_algo_ops) {
385 		pr_err("Routing algorithm '%s' is not supported\n", val);
386 		return -EINVAL;
387 	}
388 
389 	return param_set_copystring(val, kp);
390 }
391 
392 static const struct kernel_param_ops param_ops_ra = {
393 	.set = param_set_ra,
394 	.get = param_get_string,
395 };
396 
397 static struct kparam_string __param_string_ra = {
398 	.maxlen = sizeof(bat_routing_algo),
399 	.string = bat_routing_algo,
400 };
401 
402 module_param_cb(routing_algo, &param_ops_ra, &__param_string_ra, 0644);
403 module_init(batman_init);
404 module_exit(batman_exit);
405 
406 MODULE_LICENSE("GPL");
407 
408 MODULE_AUTHOR(DRIVER_AUTHOR);
409 MODULE_DESCRIPTION(DRIVER_DESC);
410 MODULE_SUPPORTED_DEVICE(DRIVER_DEVICE);
411 MODULE_VERSION(SOURCE_VERSION);
412