xref: /openbmc/linux/net/batman-adv/main.c (revision 3193e8fdfa355289892661d206d1954114a7be95)
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 batadv_hardif_list;
42 static int (*recv_packet_handler[256])(struct sk_buff *, struct hard_iface *);
43 char batadv_routing_algo[20] = "BATMAN_IV";
44 static struct hlist_head bat_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 recv_handler_init(void);
51 
52 static int __init batman_init(void)
53 {
54 	INIT_LIST_HEAD(&batadv_hardif_list);
55 	INIT_HLIST_HEAD(&bat_algo_list);
56 
57 	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 	batadv_event_workqueue = create_singlethread_workqueue("bat_events");
64 
65 	if (!batadv_event_workqueue)
66 		return -ENOMEM;
67 
68 	batadv_socket_init();
69 	batadv_debugfs_init();
70 
71 	register_netdevice_notifier(&batadv_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 	batadv_debugfs_destroy();
82 	unregister_netdevice_notifier(&batadv_hard_if_notifier);
83 	batadv_hardif_remove_interfaces();
84 
85 	flush_workqueue(batadv_event_workqueue);
86 	destroy_workqueue(batadv_event_workqueue);
87 	batadv_event_workqueue = NULL;
88 
89 	rcu_barrier();
90 }
91 
92 int batadv_mesh_init(struct net_device *soft_iface)
93 {
94 	struct bat_priv *bat_priv = netdev_priv(soft_iface);
95 	int ret;
96 
97 	spin_lock_init(&bat_priv->forw_bat_list_lock);
98 	spin_lock_init(&bat_priv->forw_bcast_list_lock);
99 	spin_lock_init(&bat_priv->tt_changes_list_lock);
100 	spin_lock_init(&bat_priv->tt_req_list_lock);
101 	spin_lock_init(&bat_priv->tt_roam_list_lock);
102 	spin_lock_init(&bat_priv->tt_buff_lock);
103 	spin_lock_init(&bat_priv->gw_list_lock);
104 	spin_lock_init(&bat_priv->vis_hash_lock);
105 	spin_lock_init(&bat_priv->vis_list_lock);
106 
107 	INIT_HLIST_HEAD(&bat_priv->forw_bat_list);
108 	INIT_HLIST_HEAD(&bat_priv->forw_bcast_list);
109 	INIT_HLIST_HEAD(&bat_priv->gw_list);
110 	INIT_LIST_HEAD(&bat_priv->tt_changes_list);
111 	INIT_LIST_HEAD(&bat_priv->tt_req_list);
112 	INIT_LIST_HEAD(&bat_priv->tt_roam_list);
113 
114 	ret = batadv_originator_init(bat_priv);
115 	if (ret < 0)
116 		goto err;
117 
118 	ret = batadv_tt_init(bat_priv);
119 	if (ret < 0)
120 		goto err;
121 
122 	batadv_tt_local_add(soft_iface, soft_iface->dev_addr, NULL_IFINDEX);
123 
124 	ret = batadv_vis_init(bat_priv);
125 	if (ret < 0)
126 		goto err;
127 
128 	ret = batadv_bla_init(bat_priv);
129 	if (ret < 0)
130 		goto err;
131 
132 	atomic_set(&bat_priv->gw_reselect, 0);
133 	atomic_set(&bat_priv->mesh_state, MESH_ACTIVE);
134 
135 	return 0;
136 
137 err:
138 	batadv_mesh_free(soft_iface);
139 	return ret;
140 }
141 
142 void batadv_mesh_free(struct net_device *soft_iface)
143 {
144 	struct bat_priv *bat_priv = netdev_priv(soft_iface);
145 
146 	atomic_set(&bat_priv->mesh_state, MESH_DEACTIVATING);
147 
148 	batadv_purge_outstanding_packets(bat_priv, NULL);
149 
150 	batadv_vis_quit(bat_priv);
151 
152 	batadv_gw_node_purge(bat_priv);
153 	batadv_originator_free(bat_priv);
154 
155 	batadv_tt_free(bat_priv);
156 
157 	batadv_bla_free(bat_priv);
158 
159 	free_percpu(bat_priv->bat_counters);
160 
161 	atomic_set(&bat_priv->mesh_state, MESH_INACTIVE);
162 }
163 
164 void batadv_inc_module_count(void)
165 {
166 	try_module_get(THIS_MODULE);
167 }
168 
169 void batadv_dec_module_count(void)
170 {
171 	module_put(THIS_MODULE);
172 }
173 
174 int batadv_is_my_mac(const uint8_t *addr)
175 {
176 	const struct hard_iface *hard_iface;
177 
178 	rcu_read_lock();
179 	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
180 		if (hard_iface->if_status != IF_ACTIVE)
181 			continue;
182 
183 		if (compare_eth(hard_iface->net_dev->dev_addr, addr)) {
184 			rcu_read_unlock();
185 			return 1;
186 		}
187 	}
188 	rcu_read_unlock();
189 	return 0;
190 }
191 
192 static int recv_unhandled_packet(struct sk_buff *skb,
193 				 struct hard_iface *recv_if)
194 {
195 	return NET_RX_DROP;
196 }
197 
198 /* incoming packets with the batman ethertype received on any active hard
199  * interface
200  */
201 int batadv_batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
202 			   struct packet_type *ptype,
203 			   struct net_device *orig_dev)
204 {
205 	struct bat_priv *bat_priv;
206 	struct batman_ogm_packet *batman_ogm_packet;
207 	struct hard_iface *hard_iface;
208 	uint8_t idx;
209 	int ret;
210 
211 	hard_iface = container_of(ptype, struct hard_iface, batman_adv_ptype);
212 	skb = skb_share_check(skb, GFP_ATOMIC);
213 
214 	/* skb was released by skb_share_check() */
215 	if (!skb)
216 		goto err_out;
217 
218 	/* packet should hold at least type and version */
219 	if (unlikely(!pskb_may_pull(skb, 2)))
220 		goto err_free;
221 
222 	/* expect a valid ethernet header here. */
223 	if (unlikely(skb->mac_len != ETH_HLEN || !skb_mac_header(skb)))
224 		goto err_free;
225 
226 	if (!hard_iface->soft_iface)
227 		goto err_free;
228 
229 	bat_priv = netdev_priv(hard_iface->soft_iface);
230 
231 	if (atomic_read(&bat_priv->mesh_state) != MESH_ACTIVE)
232 		goto err_free;
233 
234 	/* discard frames on not active interfaces */
235 	if (hard_iface->if_status != IF_ACTIVE)
236 		goto err_free;
237 
238 	batman_ogm_packet = (struct batman_ogm_packet *)skb->data;
239 
240 	if (batman_ogm_packet->header.version != COMPAT_VERSION) {
241 		bat_dbg(DBG_BATMAN, bat_priv,
242 			"Drop packet: incompatible batman version (%i)\n",
243 			batman_ogm_packet->header.version);
244 		goto err_free;
245 	}
246 
247 	/* all receive handlers return whether they received or reused
248 	 * the supplied skb. if not, we have to free the skb.
249 	 */
250 	idx = batman_ogm_packet->header.packet_type;
251 	ret = (*recv_packet_handler[idx])(skb, hard_iface);
252 
253 	if (ret == NET_RX_DROP)
254 		kfree_skb(skb);
255 
256 	/* return NET_RX_SUCCESS in any case as we
257 	 * most probably dropped the packet for
258 	 * routing-logical reasons.
259 	 */
260 	return NET_RX_SUCCESS;
261 
262 err_free:
263 	kfree_skb(skb);
264 err_out:
265 	return NET_RX_DROP;
266 }
267 
268 static void recv_handler_init(void)
269 {
270 	int i;
271 
272 	for (i = 0; i < ARRAY_SIZE(recv_packet_handler); i++)
273 		recv_packet_handler[i] = recv_unhandled_packet;
274 
275 	/* batman icmp packet */
276 	recv_packet_handler[BAT_ICMP] = batadv_recv_icmp_packet;
277 	/* unicast packet */
278 	recv_packet_handler[BAT_UNICAST] = batadv_recv_unicast_packet;
279 	/* fragmented unicast packet */
280 	recv_packet_handler[BAT_UNICAST_FRAG] = batadv_recv_ucast_frag_packet;
281 	/* broadcast packet */
282 	recv_packet_handler[BAT_BCAST] = batadv_recv_bcast_packet;
283 	/* vis packet */
284 	recv_packet_handler[BAT_VIS] = batadv_recv_vis_packet;
285 	/* Translation table query (request or response) */
286 	recv_packet_handler[BAT_TT_QUERY] = batadv_recv_tt_query;
287 	/* Roaming advertisement */
288 	recv_packet_handler[BAT_ROAM_ADV] = batadv_recv_roam_adv;
289 }
290 
291 int batadv_recv_handler_register(uint8_t packet_type,
292 				 int (*recv_handler)(struct sk_buff *,
293 						     struct hard_iface *))
294 {
295 	if (recv_packet_handler[packet_type] != &recv_unhandled_packet)
296 		return -EBUSY;
297 
298 	recv_packet_handler[packet_type] = recv_handler;
299 	return 0;
300 }
301 
302 void batadv_recv_handler_unregister(uint8_t packet_type)
303 {
304 	recv_packet_handler[packet_type] = recv_unhandled_packet;
305 }
306 
307 static struct bat_algo_ops *bat_algo_get(char *name)
308 {
309 	struct bat_algo_ops *bat_algo_ops = NULL, *bat_algo_ops_tmp;
310 	struct hlist_node *node;
311 
312 	hlist_for_each_entry(bat_algo_ops_tmp, node, &bat_algo_list, list) {
313 		if (strcmp(bat_algo_ops_tmp->name, name) != 0)
314 			continue;
315 
316 		bat_algo_ops = bat_algo_ops_tmp;
317 		break;
318 	}
319 
320 	return bat_algo_ops;
321 }
322 
323 int batadv_algo_register(struct bat_algo_ops *bat_algo_ops)
324 {
325 	struct bat_algo_ops *bat_algo_ops_tmp;
326 	int ret;
327 
328 	bat_algo_ops_tmp = bat_algo_get(bat_algo_ops->name);
329 	if (bat_algo_ops_tmp) {
330 		pr_info("Trying to register already registered routing algorithm: %s\n",
331 			bat_algo_ops->name);
332 		ret = -EEXIST;
333 		goto out;
334 	}
335 
336 	/* all algorithms must implement all ops (for now) */
337 	if (!bat_algo_ops->bat_iface_enable ||
338 	    !bat_algo_ops->bat_iface_disable ||
339 	    !bat_algo_ops->bat_iface_update_mac ||
340 	    !bat_algo_ops->bat_primary_iface_set ||
341 	    !bat_algo_ops->bat_ogm_schedule ||
342 	    !bat_algo_ops->bat_ogm_emit) {
343 		pr_info("Routing algo '%s' does not implement required ops\n",
344 			bat_algo_ops->name);
345 		ret = -EINVAL;
346 		goto out;
347 	}
348 
349 	INIT_HLIST_NODE(&bat_algo_ops->list);
350 	hlist_add_head(&bat_algo_ops->list, &bat_algo_list);
351 	ret = 0;
352 
353 out:
354 	return ret;
355 }
356 
357 int batadv_algo_select(struct bat_priv *bat_priv, char *name)
358 {
359 	struct bat_algo_ops *bat_algo_ops;
360 	int ret = -EINVAL;
361 
362 	bat_algo_ops = bat_algo_get(name);
363 	if (!bat_algo_ops)
364 		goto out;
365 
366 	bat_priv->bat_algo_ops = bat_algo_ops;
367 	ret = 0;
368 
369 out:
370 	return ret;
371 }
372 
373 int batadv_algo_seq_print_text(struct seq_file *seq, void *offset)
374 {
375 	struct bat_algo_ops *bat_algo_ops;
376 	struct hlist_node *node;
377 
378 	seq_printf(seq, "Available routing algorithms:\n");
379 
380 	hlist_for_each_entry(bat_algo_ops, node, &bat_algo_list, list) {
381 		seq_printf(seq, "%s\n", bat_algo_ops->name);
382 	}
383 
384 	return 0;
385 }
386 
387 static int param_set_ra(const char *val, const struct kernel_param *kp)
388 {
389 	struct bat_algo_ops *bat_algo_ops;
390 	char *algo_name = (char *)val;
391 	size_t name_len = strlen(algo_name);
392 
393 	if (algo_name[name_len - 1] == '\n')
394 		algo_name[name_len - 1] = '\0';
395 
396 	bat_algo_ops = bat_algo_get(algo_name);
397 	if (!bat_algo_ops) {
398 		pr_err("Routing algorithm '%s' is not supported\n", algo_name);
399 		return -EINVAL;
400 	}
401 
402 	return param_set_copystring(algo_name, kp);
403 }
404 
405 static const struct kernel_param_ops param_ops_ra = {
406 	.set = param_set_ra,
407 	.get = param_get_string,
408 };
409 
410 static struct kparam_string __param_string_ra = {
411 	.maxlen = sizeof(batadv_routing_algo),
412 	.string = batadv_routing_algo,
413 };
414 
415 module_param_cb(routing_algo, &param_ops_ra, &__param_string_ra, 0644);
416 module_init(batman_init);
417 module_exit(batman_exit);
418 
419 MODULE_LICENSE("GPL");
420 
421 MODULE_AUTHOR(DRIVER_AUTHOR);
422 MODULE_DESCRIPTION(DRIVER_DESC);
423 MODULE_SUPPORTED_DEVICE(DRIVER_DEVICE);
424 MODULE_VERSION(SOURCE_VERSION);
425