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Sven Eckelmann0046b042016-01-01 00:01:03 +01001/* Copyright (C) 2012-2016 B.A.T.M.A.N. contributors:
Martin Hundebølld353d8d2013-01-25 11:12:38 +01002 *
3 * Martin Hundebøll, Jeppe Ledet-Pedersen
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
Antonio Quartulliebf38fb2013-11-03 20:40:48 +010015 * along with this program; if not, see <http://www.gnu.org/licenses/>.
Martin Hundebølld353d8d2013-01-25 11:12:38 +010016 */
17
Martin Hundebølld353d8d2013-01-25 11:12:38 +010018#include "network-coding.h"
Sven Eckelmann1e2c2a42015-04-17 19:40:28 +020019#include "main.h"
20
21#include <linux/atomic.h>
Linus Lüssing46354692015-06-16 17:10:23 +020022#include <linux/bitops.h>
Sven Eckelmann1e2c2a42015-04-17 19:40:28 +020023#include <linux/byteorder/generic.h>
24#include <linux/compiler.h>
25#include <linux/debugfs.h>
26#include <linux/errno.h>
27#include <linux/etherdevice.h>
28#include <linux/fs.h>
29#include <linux/if_ether.h>
30#include <linux/if_packet.h>
31#include <linux/init.h>
32#include <linux/jhash.h>
33#include <linux/jiffies.h>
34#include <linux/kernel.h>
Sven Eckelmanndaf99b42016-01-16 10:29:45 +010035#include <linux/kref.h>
Sven Eckelmann1e2c2a42015-04-17 19:40:28 +020036#include <linux/list.h>
37#include <linux/lockdep.h>
38#include <linux/netdevice.h>
39#include <linux/printk.h>
40#include <linux/random.h>
41#include <linux/rculist.h>
42#include <linux/rcupdate.h>
43#include <linux/seq_file.h>
44#include <linux/skbuff.h>
45#include <linux/slab.h>
46#include <linux/spinlock.h>
47#include <linux/stat.h>
48#include <linux/stddef.h>
49#include <linux/string.h>
50#include <linux/workqueue.h>
51
Martin Hundebølld56b1702013-01-25 11:12:39 +010052#include "hard-interface.h"
Sven Eckelmann1e2c2a42015-04-17 19:40:28 +020053#include "hash.h"
54#include "originator.h"
55#include "packet.h"
Martin Hundebøll2df52782013-01-25 11:12:43 +010056#include "routing.h"
Sven Eckelmann1e2c2a42015-04-17 19:40:28 +020057#include "send.h"
Martin Hundebølld353d8d2013-01-25 11:12:38 +010058
Martin Hundebøll95332472013-01-25 11:12:40 +010059static struct lock_class_key batadv_nc_coding_hash_lock_class_key;
Martin Hundebøll612d2b42013-01-25 11:12:42 +010060static struct lock_class_key batadv_nc_decoding_hash_lock_class_key;
Martin Hundebøll95332472013-01-25 11:12:40 +010061
Martin Hundebølld353d8d2013-01-25 11:12:38 +010062static void batadv_nc_worker(struct work_struct *work);
Martin Hundebøll2df52782013-01-25 11:12:43 +010063static int batadv_nc_recv_coded_packet(struct sk_buff *skb,
64 struct batadv_hard_iface *recv_if);
Martin Hundebølld353d8d2013-01-25 11:12:38 +010065
66/**
Matthias Schiffer6c519ba2013-09-27 18:03:39 +020067 * batadv_nc_init - one-time initialization for network coding
Sven Eckelmann672e7972015-10-31 12:29:30 +010068 *
69 * Return: 0 on success or negative error number in case of failure
Matthias Schiffer6c519ba2013-09-27 18:03:39 +020070 */
71int __init batadv_nc_init(void)
72{
73 int ret;
74
75 /* Register our packet type */
76 ret = batadv_recv_handler_register(BATADV_CODED,
77 batadv_nc_recv_coded_packet);
78
79 return ret;
80}
81
82/**
Martin Hundebølld353d8d2013-01-25 11:12:38 +010083 * batadv_nc_start_timer - initialise the nc periodic worker
84 * @bat_priv: the bat priv with all the soft interface information
85 */
86static void batadv_nc_start_timer(struct batadv_priv *bat_priv)
87{
88 queue_delayed_work(batadv_event_workqueue, &bat_priv->nc.work,
89 msecs_to_jiffies(10));
90}
91
92/**
Marek Lindner3f4841f2013-04-23 21:40:00 +080093 * batadv_nc_tvlv_container_update - update the network coding tvlv container
94 * after network coding setting change
95 * @bat_priv: the bat priv with all the soft interface information
96 */
97static void batadv_nc_tvlv_container_update(struct batadv_priv *bat_priv)
98{
99 char nc_mode;
100
101 nc_mode = atomic_read(&bat_priv->network_coding);
102
103 switch (nc_mode) {
104 case 0:
105 batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_NC, 1);
106 break;
107 case 1:
108 batadv_tvlv_container_register(bat_priv, BATADV_TVLV_NC, 1,
109 NULL, 0);
110 break;
111 }
112}
113
114/**
115 * batadv_nc_status_update - update the network coding tvlv container after
116 * network coding setting change
117 * @net_dev: the soft interface net device
118 */
119void batadv_nc_status_update(struct net_device *net_dev)
120{
121 struct batadv_priv *bat_priv = netdev_priv(net_dev);
Antonio Quartullif1386942014-05-10 18:56:37 +0200122
Marek Lindner3f4841f2013-04-23 21:40:00 +0800123 batadv_nc_tvlv_container_update(bat_priv);
124}
125
126/**
127 * batadv_nc_tvlv_ogm_handler_v1 - process incoming nc tvlv container
128 * @bat_priv: the bat priv with all the soft interface information
129 * @orig: the orig_node of the ogm
130 * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
131 * @tvlv_value: tvlv buffer containing the gateway data
132 * @tvlv_value_len: tvlv buffer length
133 */
134static void batadv_nc_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
135 struct batadv_orig_node *orig,
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200136 u8 flags,
137 void *tvlv_value, u16 tvlv_value_len)
Marek Lindner3f4841f2013-04-23 21:40:00 +0800138{
139 if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND)
Linus Lüssing46354692015-06-16 17:10:23 +0200140 clear_bit(BATADV_ORIG_CAPA_HAS_NC, &orig->capabilities);
Marek Lindner3f4841f2013-04-23 21:40:00 +0800141 else
Linus Lüssing46354692015-06-16 17:10:23 +0200142 set_bit(BATADV_ORIG_CAPA_HAS_NC, &orig->capabilities);
Marek Lindner3f4841f2013-04-23 21:40:00 +0800143}
144
145/**
Matthias Schiffer6c519ba2013-09-27 18:03:39 +0200146 * batadv_nc_mesh_init - initialise coding hash table and start house keeping
Martin Hundebølld353d8d2013-01-25 11:12:38 +0100147 * @bat_priv: the bat priv with all the soft interface information
Sven Eckelmann672e7972015-10-31 12:29:30 +0100148 *
149 * Return: 0 on success or negative error number in case of failure
Martin Hundebølld353d8d2013-01-25 11:12:38 +0100150 */
Matthias Schiffer6c519ba2013-09-27 18:03:39 +0200151int batadv_nc_mesh_init(struct batadv_priv *bat_priv)
Martin Hundebølld353d8d2013-01-25 11:12:38 +0100152{
Martin Hundebøll95332472013-01-25 11:12:40 +0100153 bat_priv->nc.timestamp_fwd_flush = jiffies;
Martin Hundebøll612d2b42013-01-25 11:12:42 +0100154 bat_priv->nc.timestamp_sniffed_purge = jiffies;
Martin Hundebøll95332472013-01-25 11:12:40 +0100155
Martin Hundebøll612d2b42013-01-25 11:12:42 +0100156 if (bat_priv->nc.coding_hash || bat_priv->nc.decoding_hash)
Martin Hundebøll95332472013-01-25 11:12:40 +0100157 return 0;
158
159 bat_priv->nc.coding_hash = batadv_hash_new(128);
160 if (!bat_priv->nc.coding_hash)
161 goto err;
162
163 batadv_hash_set_lock_class(bat_priv->nc.coding_hash,
164 &batadv_nc_coding_hash_lock_class_key);
165
Martin Hundebøll612d2b42013-01-25 11:12:42 +0100166 bat_priv->nc.decoding_hash = batadv_hash_new(128);
167 if (!bat_priv->nc.decoding_hash)
168 goto err;
169
Martin Hundebøllf44d5402014-11-11 16:22:23 +0100170 batadv_hash_set_lock_class(bat_priv->nc.decoding_hash,
Martin Hundebøll612d2b42013-01-25 11:12:42 +0100171 &batadv_nc_decoding_hash_lock_class_key);
172
Martin Hundebølld353d8d2013-01-25 11:12:38 +0100173 INIT_DELAYED_WORK(&bat_priv->nc.work, batadv_nc_worker);
174 batadv_nc_start_timer(bat_priv);
175
Marek Lindner3f4841f2013-04-23 21:40:00 +0800176 batadv_tvlv_handler_register(bat_priv, batadv_nc_tvlv_ogm_handler_v1,
177 NULL, BATADV_TVLV_NC, 1,
178 BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
179 batadv_nc_tvlv_container_update(bat_priv);
Martin Hundebølld353d8d2013-01-25 11:12:38 +0100180 return 0;
Martin Hundebøll95332472013-01-25 11:12:40 +0100181
182err:
183 return -ENOMEM;
Martin Hundebølld353d8d2013-01-25 11:12:38 +0100184}
185
186/**
187 * batadv_nc_init_bat_priv - initialise the nc specific bat_priv variables
188 * @bat_priv: the bat priv with all the soft interface information
189 */
190void batadv_nc_init_bat_priv(struct batadv_priv *bat_priv)
191{
Sven Eckelmanndab7b622015-02-18 18:20:24 +0100192 atomic_set(&bat_priv->network_coding, 0);
Martin Hundebølld56b1702013-01-25 11:12:39 +0100193 bat_priv->nc.min_tq = 200;
Martin Hundebøll95332472013-01-25 11:12:40 +0100194 bat_priv->nc.max_fwd_delay = 10;
Martin Hundebøll612d2b42013-01-25 11:12:42 +0100195 bat_priv->nc.max_buffer_time = 200;
Martin Hundebølld56b1702013-01-25 11:12:39 +0100196}
197
198/**
199 * batadv_nc_init_orig - initialise the nc fields of an orig_node
200 * @orig_node: the orig_node which is going to be initialised
201 */
202void batadv_nc_init_orig(struct batadv_orig_node *orig_node)
203{
204 INIT_LIST_HEAD(&orig_node->in_coding_list);
205 INIT_LIST_HEAD(&orig_node->out_coding_list);
206 spin_lock_init(&orig_node->in_coding_list_lock);
207 spin_lock_init(&orig_node->out_coding_list_lock);
208}
209
210/**
Sven Eckelmann44e8e7e92016-01-05 12:06:19 +0100211 * batadv_nc_node_release - release nc_node from lists and queue for free after
212 * rcu grace period
Sven Eckelmanndaf99b42016-01-16 10:29:45 +0100213 * @ref: kref pointer of the nc_node
Martin Hundebølld56b1702013-01-25 11:12:39 +0100214 */
Sven Eckelmanndaf99b42016-01-16 10:29:45 +0100215static void batadv_nc_node_release(struct kref *ref)
Martin Hundebølld56b1702013-01-25 11:12:39 +0100216{
Sven Eckelmanndaf99b42016-01-16 10:29:45 +0100217 struct batadv_nc_node *nc_node;
218
219 nc_node = container_of(ref, struct batadv_nc_node, refcount);
220
Martin Hundebølld56b1702013-01-25 11:12:39 +0100221 batadv_orig_node_free_ref(nc_node->orig_node);
Sven Eckelmann44e8e7e92016-01-05 12:06:19 +0100222 kfree_rcu(nc_node, rcu);
Martin Hundebølld56b1702013-01-25 11:12:39 +0100223}
224
225/**
Sven Eckelmanndaf99b42016-01-16 10:29:45 +0100226 * batadv_nc_node_free_ref - decrement the nc_node refcounter and possibly
Sven Eckelmann44e8e7e92016-01-05 12:06:19 +0100227 * release it
Sven Eckelmanndaf99b42016-01-16 10:29:45 +0100228 * @nc_node: nc_node to be free'd
Martin Hundebølld56b1702013-01-25 11:12:39 +0100229 */
230static void batadv_nc_node_free_ref(struct batadv_nc_node *nc_node)
231{
Sven Eckelmanndaf99b42016-01-16 10:29:45 +0100232 kref_put(&nc_node->refcount, batadv_nc_node_release);
Martin Hundebølld56b1702013-01-25 11:12:39 +0100233}
234
235/**
Sven Eckelmann727e0cd2016-01-16 10:29:46 +0100236 * batadv_nc_path_release - release nc_path from lists and queue for free after
237 * rcu grace period
238 * @ref: kref pointer of the nc_path
239 */
240static void batadv_nc_path_release(struct kref *ref)
241{
242 struct batadv_nc_path *nc_path;
243
244 nc_path = container_of(ref, struct batadv_nc_path, refcount);
245
246 kfree_rcu(nc_path, rcu);
247}
248
249/**
250 * batadv_nc_path_free_ref - decrement the nc_path refcounter and possibly
251 * release it
252 * @nc_path: nc_path to be free'd
Martin Hundebøll95332472013-01-25 11:12:40 +0100253 */
254static void batadv_nc_path_free_ref(struct batadv_nc_path *nc_path)
255{
Sven Eckelmann727e0cd2016-01-16 10:29:46 +0100256 kref_put(&nc_path->refcount, batadv_nc_path_release);
Martin Hundebøll95332472013-01-25 11:12:40 +0100257}
258
259/**
260 * batadv_nc_packet_free - frees nc packet
261 * @nc_packet: the nc packet to free
262 */
263static void batadv_nc_packet_free(struct batadv_nc_packet *nc_packet)
264{
Markus Elfringc7994432015-11-15 08:04:43 +0100265 kfree_skb(nc_packet->skb);
Martin Hundebøll95332472013-01-25 11:12:40 +0100266 batadv_nc_path_free_ref(nc_packet->nc_path);
267 kfree(nc_packet);
268}
269
270/**
Martin Hundebølld56b1702013-01-25 11:12:39 +0100271 * batadv_nc_to_purge_nc_node - checks whether an nc node has to be purged
272 * @bat_priv: the bat priv with all the soft interface information
273 * @nc_node: the nc node to check
274 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200275 * Return: true if the entry has to be purged now, false otherwise
Martin Hundebølld56b1702013-01-25 11:12:39 +0100276 */
277static bool batadv_nc_to_purge_nc_node(struct batadv_priv *bat_priv,
278 struct batadv_nc_node *nc_node)
279{
280 if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
281 return true;
282
283 return batadv_has_timed_out(nc_node->last_seen, BATADV_NC_NODE_TIMEOUT);
284}
285
286/**
Martin Hundebøll95332472013-01-25 11:12:40 +0100287 * batadv_nc_to_purge_nc_path_coding - checks whether an nc path has timed out
288 * @bat_priv: the bat priv with all the soft interface information
289 * @nc_path: the nc path to check
290 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200291 * Return: true if the entry has to be purged now, false otherwise
Martin Hundebøll95332472013-01-25 11:12:40 +0100292 */
293static bool batadv_nc_to_purge_nc_path_coding(struct batadv_priv *bat_priv,
294 struct batadv_nc_path *nc_path)
295{
296 if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
297 return true;
298
299 /* purge the path when no packets has been added for 10 times the
300 * max_fwd_delay time
301 */
302 return batadv_has_timed_out(nc_path->last_valid,
303 bat_priv->nc.max_fwd_delay * 10);
304}
305
306/**
Martin Hundebøll612d2b42013-01-25 11:12:42 +0100307 * batadv_nc_to_purge_nc_path_decoding - checks whether an nc path has timed out
308 * @bat_priv: the bat priv with all the soft interface information
309 * @nc_path: the nc path to check
310 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200311 * Return: true if the entry has to be purged now, false otherwise
Martin Hundebøll612d2b42013-01-25 11:12:42 +0100312 */
313static bool batadv_nc_to_purge_nc_path_decoding(struct batadv_priv *bat_priv,
314 struct batadv_nc_path *nc_path)
315{
316 if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
317 return true;
318
319 /* purge the path when no packets has been added for 10 times the
320 * max_buffer time
321 */
322 return batadv_has_timed_out(nc_path->last_valid,
Marek Lindnerfc1f8692015-02-18 22:19:20 +0800323 bat_priv->nc.max_buffer_time * 10);
Martin Hundebøll612d2b42013-01-25 11:12:42 +0100324}
325
326/**
Martin Hundebølld56b1702013-01-25 11:12:39 +0100327 * batadv_nc_purge_orig_nc_nodes - go through list of nc nodes and purge stale
328 * entries
329 * @bat_priv: the bat priv with all the soft interface information
330 * @list: list of nc nodes
331 * @lock: nc node list lock
332 * @to_purge: function in charge to decide whether an entry has to be purged or
333 * not. This function takes the nc node as argument and has to return
334 * a boolean value: true if the entry has to be deleted, false
335 * otherwise
336 */
337static void
338batadv_nc_purge_orig_nc_nodes(struct batadv_priv *bat_priv,
339 struct list_head *list,
340 spinlock_t *lock,
341 bool (*to_purge)(struct batadv_priv *,
342 struct batadv_nc_node *))
343{
344 struct batadv_nc_node *nc_node, *nc_node_tmp;
345
346 /* For each nc_node in list */
347 spin_lock_bh(lock);
348 list_for_each_entry_safe(nc_node, nc_node_tmp, list, list) {
349 /* if an helper function has been passed as parameter,
350 * ask it if the entry has to be purged or not
351 */
352 if (to_purge && !to_purge(bat_priv, nc_node))
353 continue;
354
355 batadv_dbg(BATADV_DBG_NC, bat_priv,
356 "Removing nc_node %pM -> %pM\n",
357 nc_node->addr, nc_node->orig_node->orig);
358 list_del_rcu(&nc_node->list);
359 batadv_nc_node_free_ref(nc_node);
360 }
361 spin_unlock_bh(lock);
362}
363
364/**
365 * batadv_nc_purge_orig - purges all nc node data attached of the given
366 * originator
367 * @bat_priv: the bat priv with all the soft interface information
368 * @orig_node: orig_node with the nc node entries to be purged
369 * @to_purge: function in charge to decide whether an entry has to be purged or
370 * not. This function takes the nc node as argument and has to return
371 * a boolean value: true is the entry has to be deleted, false
372 * otherwise
373 */
374void batadv_nc_purge_orig(struct batadv_priv *bat_priv,
375 struct batadv_orig_node *orig_node,
376 bool (*to_purge)(struct batadv_priv *,
377 struct batadv_nc_node *))
378{
379 /* Check ingoing nc_node's of this orig_node */
380 batadv_nc_purge_orig_nc_nodes(bat_priv, &orig_node->in_coding_list,
381 &orig_node->in_coding_list_lock,
382 to_purge);
383
384 /* Check outgoing nc_node's of this orig_node */
385 batadv_nc_purge_orig_nc_nodes(bat_priv, &orig_node->out_coding_list,
386 &orig_node->out_coding_list_lock,
387 to_purge);
388}
389
390/**
391 * batadv_nc_purge_orig_hash - traverse entire originator hash to check if they
392 * have timed out nc nodes
393 * @bat_priv: the bat priv with all the soft interface information
394 */
395static void batadv_nc_purge_orig_hash(struct batadv_priv *bat_priv)
396{
397 struct batadv_hashtable *hash = bat_priv->orig_hash;
398 struct hlist_head *head;
399 struct batadv_orig_node *orig_node;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200400 u32 i;
Martin Hundebølld56b1702013-01-25 11:12:39 +0100401
402 if (!hash)
403 return;
404
405 /* For each orig_node */
406 for (i = 0; i < hash->size; i++) {
407 head = &hash->table[i];
408
409 rcu_read_lock();
410 hlist_for_each_entry_rcu(orig_node, head, hash_entry)
411 batadv_nc_purge_orig(bat_priv, orig_node,
412 batadv_nc_to_purge_nc_node);
413 rcu_read_unlock();
414 }
Martin Hundebølld353d8d2013-01-25 11:12:38 +0100415}
416
417/**
Martin Hundebøll95332472013-01-25 11:12:40 +0100418 * batadv_nc_purge_paths - traverse all nc paths part of the hash and remove
419 * unused ones
420 * @bat_priv: the bat priv with all the soft interface information
421 * @hash: hash table containing the nc paths to check
422 * @to_purge: function in charge to decide whether an entry has to be purged or
423 * not. This function takes the nc node as argument and has to return
424 * a boolean value: true is the entry has to be deleted, false
425 * otherwise
426 */
427static void batadv_nc_purge_paths(struct batadv_priv *bat_priv,
428 struct batadv_hashtable *hash,
429 bool (*to_purge)(struct batadv_priv *,
430 struct batadv_nc_path *))
431{
432 struct hlist_head *head;
433 struct hlist_node *node_tmp;
434 struct batadv_nc_path *nc_path;
435 spinlock_t *lock; /* Protects lists in hash */
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200436 u32 i;
Martin Hundebøll95332472013-01-25 11:12:40 +0100437
438 for (i = 0; i < hash->size; i++) {
439 head = &hash->table[i];
440 lock = &hash->list_locks[i];
441
442 /* For each nc_path in this bin */
443 spin_lock_bh(lock);
444 hlist_for_each_entry_safe(nc_path, node_tmp, head, hash_entry) {
445 /* if an helper function has been passed as parameter,
446 * ask it if the entry has to be purged or not
447 */
448 if (to_purge && !to_purge(bat_priv, nc_path))
449 continue;
450
451 /* purging an non-empty nc_path should never happen, but
452 * is observed under high CPU load. Delay the purging
453 * until next iteration to allow the packet_list to be
454 * emptied first.
455 */
456 if (!unlikely(list_empty(&nc_path->packet_list))) {
457 net_ratelimited_function(printk,
458 KERN_WARNING
459 "Skipping free of non-empty nc_path (%pM -> %pM)!\n",
460 nc_path->prev_hop,
461 nc_path->next_hop);
462 continue;
463 }
464
465 /* nc_path is unused, so remove it */
466 batadv_dbg(BATADV_DBG_NC, bat_priv,
467 "Remove nc_path %pM -> %pM\n",
468 nc_path->prev_hop, nc_path->next_hop);
469 hlist_del_rcu(&nc_path->hash_entry);
470 batadv_nc_path_free_ref(nc_path);
471 }
472 spin_unlock_bh(lock);
473 }
474}
475
476/**
477 * batadv_nc_hash_key_gen - computes the nc_path hash key
478 * @key: buffer to hold the final hash key
479 * @src: source ethernet mac address going into the hash key
480 * @dst: destination ethernet mac address going into the hash key
481 */
482static void batadv_nc_hash_key_gen(struct batadv_nc_path *key, const char *src,
483 const char *dst)
484{
485 memcpy(key->prev_hop, src, sizeof(key->prev_hop));
486 memcpy(key->next_hop, dst, sizeof(key->next_hop));
487}
488
489/**
490 * batadv_nc_hash_choose - compute the hash value for an nc path
491 * @data: data to hash
492 * @size: size of the hash table
493 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200494 * Return: the selected index in the hash table for the given data.
Martin Hundebøll95332472013-01-25 11:12:40 +0100495 */
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200496static u32 batadv_nc_hash_choose(const void *data, u32 size)
Martin Hundebøll95332472013-01-25 11:12:40 +0100497{
498 const struct batadv_nc_path *nc_path = data;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200499 u32 hash = 0;
Martin Hundebøll95332472013-01-25 11:12:40 +0100500
Sven Eckelmann36fd61c2015-03-01 09:46:18 +0100501 hash = jhash(&nc_path->prev_hop, sizeof(nc_path->prev_hop), hash);
502 hash = jhash(&nc_path->next_hop, sizeof(nc_path->next_hop), hash);
Martin Hundebøll95332472013-01-25 11:12:40 +0100503
504 return hash % size;
505}
506
507/**
508 * batadv_nc_hash_compare - comparing function used in the network coding hash
509 * tables
510 * @node: node in the local table
511 * @data2: second object to compare the node to
512 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200513 * Return: 1 if the two entry are the same, 0 otherwise
Martin Hundebøll95332472013-01-25 11:12:40 +0100514 */
515static int batadv_nc_hash_compare(const struct hlist_node *node,
516 const void *data2)
517{
518 const struct batadv_nc_path *nc_path1, *nc_path2;
519
520 nc_path1 = container_of(node, struct batadv_nc_path, hash_entry);
521 nc_path2 = data2;
522
523 /* Return 1 if the two keys are identical */
524 if (memcmp(nc_path1->prev_hop, nc_path2->prev_hop,
525 sizeof(nc_path1->prev_hop)) != 0)
526 return 0;
527
528 if (memcmp(nc_path1->next_hop, nc_path2->next_hop,
529 sizeof(nc_path1->next_hop)) != 0)
530 return 0;
531
532 return 1;
533}
534
535/**
536 * batadv_nc_hash_find - search for an existing nc path and return it
537 * @hash: hash table containing the nc path
538 * @data: search key
539 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200540 * Return: the nc_path if found, NULL otherwise.
Martin Hundebøll95332472013-01-25 11:12:40 +0100541 */
542static struct batadv_nc_path *
543batadv_nc_hash_find(struct batadv_hashtable *hash,
544 void *data)
545{
546 struct hlist_head *head;
547 struct batadv_nc_path *nc_path, *nc_path_tmp = NULL;
548 int index;
549
550 if (!hash)
551 return NULL;
552
553 index = batadv_nc_hash_choose(data, hash->size);
554 head = &hash->table[index];
555
556 rcu_read_lock();
557 hlist_for_each_entry_rcu(nc_path, head, hash_entry) {
558 if (!batadv_nc_hash_compare(&nc_path->hash_entry, data))
559 continue;
560
Sven Eckelmann727e0cd2016-01-16 10:29:46 +0100561 if (!kref_get_unless_zero(&nc_path->refcount))
Martin Hundebøll95332472013-01-25 11:12:40 +0100562 continue;
563
564 nc_path_tmp = nc_path;
565 break;
566 }
567 rcu_read_unlock();
568
569 return nc_path_tmp;
570}
571
572/**
573 * batadv_nc_send_packet - send non-coded packet and free nc_packet struct
574 * @nc_packet: the nc packet to send
575 */
576static void batadv_nc_send_packet(struct batadv_nc_packet *nc_packet)
577{
578 batadv_send_skb_packet(nc_packet->skb,
579 nc_packet->neigh_node->if_incoming,
580 nc_packet->nc_path->next_hop);
581 nc_packet->skb = NULL;
582 batadv_nc_packet_free(nc_packet);
583}
584
585/**
Martin Hundebøll612d2b42013-01-25 11:12:42 +0100586 * batadv_nc_sniffed_purge - Checks timestamp of given sniffed nc_packet.
587 * @bat_priv: the bat priv with all the soft interface information
588 * @nc_path: the nc path the packet belongs to
589 * @nc_packet: the nc packet to be checked
590 *
591 * Checks whether the given sniffed (overheard) nc_packet has hit its buffering
592 * timeout. If so, the packet is no longer kept and the entry deleted from the
593 * queue. Has to be called with the appropriate locks.
594 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200595 * Return: false as soon as the entry in the fifo queue has not been timed out
Martin Hundebøll612d2b42013-01-25 11:12:42 +0100596 * yet and true otherwise.
597 */
598static bool batadv_nc_sniffed_purge(struct batadv_priv *bat_priv,
599 struct batadv_nc_path *nc_path,
600 struct batadv_nc_packet *nc_packet)
601{
602 unsigned long timeout = bat_priv->nc.max_buffer_time;
603 bool res = false;
604
Sven Eckelmann2c72d652015-06-21 14:45:14 +0200605 lockdep_assert_held(&nc_path->packet_list_lock);
606
Martin Hundebøll612d2b42013-01-25 11:12:42 +0100607 /* Packets are added to tail, so the remaining packets did not time
608 * out and we can stop processing the current queue
609 */
610 if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_ACTIVE &&
611 !batadv_has_timed_out(nc_packet->timestamp, timeout))
612 goto out;
613
614 /* purge nc packet */
615 list_del(&nc_packet->list);
616 batadv_nc_packet_free(nc_packet);
617
618 res = true;
619
620out:
621 return res;
622}
623
624/**
Martin Hundebøll95332472013-01-25 11:12:40 +0100625 * batadv_nc_fwd_flush - Checks the timestamp of the given nc packet.
626 * @bat_priv: the bat priv with all the soft interface information
627 * @nc_path: the nc path the packet belongs to
628 * @nc_packet: the nc packet to be checked
629 *
630 * Checks whether the given nc packet has hit its forward timeout. If so, the
631 * packet is no longer delayed, immediately sent and the entry deleted from the
632 * queue. Has to be called with the appropriate locks.
633 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200634 * Return: false as soon as the entry in the fifo queue has not been timed out
Martin Hundebøll95332472013-01-25 11:12:40 +0100635 * yet and true otherwise.
636 */
637static bool batadv_nc_fwd_flush(struct batadv_priv *bat_priv,
638 struct batadv_nc_path *nc_path,
639 struct batadv_nc_packet *nc_packet)
640{
641 unsigned long timeout = bat_priv->nc.max_fwd_delay;
642
Sven Eckelmann2c72d652015-06-21 14:45:14 +0200643 lockdep_assert_held(&nc_path->packet_list_lock);
644
Martin Hundebøll95332472013-01-25 11:12:40 +0100645 /* Packets are added to tail, so the remaining packets did not time
646 * out and we can stop processing the current queue
647 */
648 if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_ACTIVE &&
649 !batadv_has_timed_out(nc_packet->timestamp, timeout))
650 return false;
651
652 /* Send packet */
653 batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD);
654 batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES,
655 nc_packet->skb->len + ETH_HLEN);
656 list_del(&nc_packet->list);
657 batadv_nc_send_packet(nc_packet);
658
659 return true;
660}
661
662/**
663 * batadv_nc_process_nc_paths - traverse given nc packet pool and free timed out
664 * nc packets
665 * @bat_priv: the bat priv with all the soft interface information
666 * @hash: to be processed hash table
667 * @process_fn: Function called to process given nc packet. Should return true
668 * to encourage this function to proceed with the next packet.
669 * Otherwise the rest of the current queue is skipped.
670 */
671static void
672batadv_nc_process_nc_paths(struct batadv_priv *bat_priv,
673 struct batadv_hashtable *hash,
674 bool (*process_fn)(struct batadv_priv *,
675 struct batadv_nc_path *,
676 struct batadv_nc_packet *))
677{
678 struct hlist_head *head;
679 struct batadv_nc_packet *nc_packet, *nc_packet_tmp;
680 struct batadv_nc_path *nc_path;
681 bool ret;
682 int i;
683
684 if (!hash)
685 return;
686
687 /* Loop hash table bins */
688 for (i = 0; i < hash->size; i++) {
689 head = &hash->table[i];
690
691 /* Loop coding paths */
692 rcu_read_lock();
693 hlist_for_each_entry_rcu(nc_path, head, hash_entry) {
694 /* Loop packets */
695 spin_lock_bh(&nc_path->packet_list_lock);
696 list_for_each_entry_safe(nc_packet, nc_packet_tmp,
697 &nc_path->packet_list, list) {
698 ret = process_fn(bat_priv, nc_path, nc_packet);
699 if (!ret)
700 break;
701 }
702 spin_unlock_bh(&nc_path->packet_list_lock);
703 }
704 rcu_read_unlock();
705 }
706}
707
708/**
Martin Hundebølld353d8d2013-01-25 11:12:38 +0100709 * batadv_nc_worker - periodic task for house keeping related to network coding
710 * @work: kernel work struct
711 */
712static void batadv_nc_worker(struct work_struct *work)
713{
714 struct delayed_work *delayed_work;
715 struct batadv_priv_nc *priv_nc;
716 struct batadv_priv *bat_priv;
Martin Hundebøll95332472013-01-25 11:12:40 +0100717 unsigned long timeout;
Martin Hundebølld353d8d2013-01-25 11:12:38 +0100718
719 delayed_work = container_of(work, struct delayed_work, work);
720 priv_nc = container_of(delayed_work, struct batadv_priv_nc, work);
721 bat_priv = container_of(priv_nc, struct batadv_priv, nc);
722
Martin Hundebølld56b1702013-01-25 11:12:39 +0100723 batadv_nc_purge_orig_hash(bat_priv);
Martin Hundebøll95332472013-01-25 11:12:40 +0100724 batadv_nc_purge_paths(bat_priv, bat_priv->nc.coding_hash,
725 batadv_nc_to_purge_nc_path_coding);
Martin Hundebøll612d2b42013-01-25 11:12:42 +0100726 batadv_nc_purge_paths(bat_priv, bat_priv->nc.decoding_hash,
727 batadv_nc_to_purge_nc_path_decoding);
Martin Hundebøll95332472013-01-25 11:12:40 +0100728
729 timeout = bat_priv->nc.max_fwd_delay;
730
731 if (batadv_has_timed_out(bat_priv->nc.timestamp_fwd_flush, timeout)) {
732 batadv_nc_process_nc_paths(bat_priv, bat_priv->nc.coding_hash,
733 batadv_nc_fwd_flush);
734 bat_priv->nc.timestamp_fwd_flush = jiffies;
735 }
Martin Hundebølld56b1702013-01-25 11:12:39 +0100736
Martin Hundebøll612d2b42013-01-25 11:12:42 +0100737 if (batadv_has_timed_out(bat_priv->nc.timestamp_sniffed_purge,
738 bat_priv->nc.max_buffer_time)) {
739 batadv_nc_process_nc_paths(bat_priv, bat_priv->nc.decoding_hash,
740 batadv_nc_sniffed_purge);
741 bat_priv->nc.timestamp_sniffed_purge = jiffies;
742 }
743
Martin Hundebølld353d8d2013-01-25 11:12:38 +0100744 /* Schedule a new check */
745 batadv_nc_start_timer(bat_priv);
746}
747
748/**
Martin Hundebølld56b1702013-01-25 11:12:39 +0100749 * batadv_can_nc_with_orig - checks whether the given orig node is suitable for
750 * coding or not
751 * @bat_priv: the bat priv with all the soft interface information
752 * @orig_node: neighboring orig node which may be used as nc candidate
753 * @ogm_packet: incoming ogm packet also used for the checks
754 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200755 * Return: true if:
Martin Hundebølld56b1702013-01-25 11:12:39 +0100756 * 1) The OGM must have the most recent sequence number.
757 * 2) The TTL must be decremented by one and only one.
758 * 3) The OGM must be received from the first hop from orig_node.
759 * 4) The TQ value of the OGM must be above bat_priv->nc.min_tq.
760 */
761static bool batadv_can_nc_with_orig(struct batadv_priv *bat_priv,
762 struct batadv_orig_node *orig_node,
763 struct batadv_ogm_packet *ogm_packet)
764{
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100765 struct batadv_orig_ifinfo *orig_ifinfo;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200766 u32 last_real_seqno;
767 u8 last_ttl;
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100768
769 orig_ifinfo = batadv_orig_ifinfo_get(orig_node, BATADV_IF_DEFAULT);
770 if (!orig_ifinfo)
Martin Hundebølld56b1702013-01-25 11:12:39 +0100771 return false;
Simon Wunderlich7351a4822013-11-13 19:14:47 +0100772
773 last_ttl = orig_ifinfo->last_ttl;
774 last_real_seqno = orig_ifinfo->last_real_seqno;
775 batadv_orig_ifinfo_free_ref(orig_ifinfo);
776
777 if (last_real_seqno != ntohl(ogm_packet->seqno))
778 return false;
779 if (last_ttl != ogm_packet->ttl + 1)
Martin Hundebølld56b1702013-01-25 11:12:39 +0100780 return false;
781 if (!batadv_compare_eth(ogm_packet->orig, ogm_packet->prev_sender))
782 return false;
783 if (ogm_packet->tq < bat_priv->nc.min_tq)
784 return false;
785
786 return true;
787}
788
789/**
790 * batadv_nc_find_nc_node - search for an existing nc node and return it
791 * @orig_node: orig node originating the ogm packet
792 * @orig_neigh_node: neighboring orig node from which we received the ogm packet
793 * (can be equal to orig_node)
794 * @in_coding: traverse incoming or outgoing network coding list
795 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200796 * Return: the nc_node if found, NULL otherwise.
Martin Hundebølld56b1702013-01-25 11:12:39 +0100797 */
798static struct batadv_nc_node
799*batadv_nc_find_nc_node(struct batadv_orig_node *orig_node,
800 struct batadv_orig_node *orig_neigh_node,
801 bool in_coding)
802{
803 struct batadv_nc_node *nc_node, *nc_node_out = NULL;
804 struct list_head *list;
805
806 if (in_coding)
807 list = &orig_neigh_node->in_coding_list;
808 else
809 list = &orig_neigh_node->out_coding_list;
810
811 /* Traverse list of nc_nodes to orig_node */
812 rcu_read_lock();
813 list_for_each_entry_rcu(nc_node, list, list) {
814 if (!batadv_compare_eth(nc_node->addr, orig_node->orig))
815 continue;
816
Sven Eckelmanndaf99b42016-01-16 10:29:45 +0100817 if (!kref_get_unless_zero(&nc_node->refcount))
Martin Hundebølld56b1702013-01-25 11:12:39 +0100818 continue;
819
820 /* Found a match */
821 nc_node_out = nc_node;
822 break;
823 }
824 rcu_read_unlock();
825
826 return nc_node_out;
827}
828
829/**
830 * batadv_nc_get_nc_node - retrieves an nc node or creates the entry if it was
831 * not found
832 * @bat_priv: the bat priv with all the soft interface information
833 * @orig_node: orig node originating the ogm packet
834 * @orig_neigh_node: neighboring orig node from which we received the ogm packet
835 * (can be equal to orig_node)
836 * @in_coding: traverse incoming or outgoing network coding list
837 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200838 * Return: the nc_node if found or created, NULL in case of an error.
Martin Hundebølld56b1702013-01-25 11:12:39 +0100839 */
840static struct batadv_nc_node
841*batadv_nc_get_nc_node(struct batadv_priv *bat_priv,
842 struct batadv_orig_node *orig_node,
843 struct batadv_orig_node *orig_neigh_node,
844 bool in_coding)
845{
846 struct batadv_nc_node *nc_node;
847 spinlock_t *lock; /* Used to lock list selected by "int in_coding" */
848 struct list_head *list;
849
850 /* Check if nc_node is already added */
851 nc_node = batadv_nc_find_nc_node(orig_node, orig_neigh_node, in_coding);
852
853 /* Node found */
854 if (nc_node)
855 return nc_node;
856
857 nc_node = kzalloc(sizeof(*nc_node), GFP_ATOMIC);
858 if (!nc_node)
859 return NULL;
860
Sven Eckelmann7c124392016-01-16 10:29:56 +0100861 if (!kref_get_unless_zero(&orig_neigh_node->refcount))
Martin Hundebølld56b1702013-01-25 11:12:39 +0100862 goto free;
863
864 /* Initialize nc_node */
865 INIT_LIST_HEAD(&nc_node->list);
Antonio Quartulli8fdd0152014-01-22 00:42:11 +0100866 ether_addr_copy(nc_node->addr, orig_node->orig);
Martin Hundebølld56b1702013-01-25 11:12:39 +0100867 nc_node->orig_node = orig_neigh_node;
Sven Eckelmanndaf99b42016-01-16 10:29:45 +0100868 kref_init(&nc_node->refcount);
869 kref_get(&nc_node->refcount);
Martin Hundebølld56b1702013-01-25 11:12:39 +0100870
871 /* Select ingoing or outgoing coding node */
872 if (in_coding) {
873 lock = &orig_neigh_node->in_coding_list_lock;
874 list = &orig_neigh_node->in_coding_list;
875 } else {
876 lock = &orig_neigh_node->out_coding_list_lock;
877 list = &orig_neigh_node->out_coding_list;
878 }
879
880 batadv_dbg(BATADV_DBG_NC, bat_priv, "Adding nc_node %pM -> %pM\n",
881 nc_node->addr, nc_node->orig_node->orig);
882
883 /* Add nc_node to orig_node */
884 spin_lock_bh(lock);
885 list_add_tail_rcu(&nc_node->list, list);
886 spin_unlock_bh(lock);
887
888 return nc_node;
889
890free:
891 kfree(nc_node);
892 return NULL;
893}
894
895/**
Sven Eckelmann34473822015-05-31 10:10:20 +0200896 * batadv_nc_update_nc_node - updates stored incoming and outgoing nc node
897 * structs (best called on incoming OGMs)
Martin Hundebølld56b1702013-01-25 11:12:39 +0100898 * @bat_priv: the bat priv with all the soft interface information
899 * @orig_node: orig node originating the ogm packet
900 * @orig_neigh_node: neighboring orig node from which we received the ogm packet
901 * (can be equal to orig_node)
902 * @ogm_packet: incoming ogm packet
903 * @is_single_hop_neigh: orig_node is a single hop neighbor
904 */
905void batadv_nc_update_nc_node(struct batadv_priv *bat_priv,
906 struct batadv_orig_node *orig_node,
907 struct batadv_orig_node *orig_neigh_node,
908 struct batadv_ogm_packet *ogm_packet,
909 int is_single_hop_neigh)
910{
Sven Eckelmann4f248cf2015-06-09 20:50:49 +0200911 struct batadv_nc_node *in_nc_node = NULL;
912 struct batadv_nc_node *out_nc_node = NULL;
Martin Hundebølld56b1702013-01-25 11:12:39 +0100913
914 /* Check if network coding is enabled */
915 if (!atomic_read(&bat_priv->network_coding))
916 goto out;
917
Marek Lindner3f4841f2013-04-23 21:40:00 +0800918 /* check if orig node is network coding enabled */
Linus Lüssing46354692015-06-16 17:10:23 +0200919 if (!test_bit(BATADV_ORIG_CAPA_HAS_NC, &orig_node->capabilities))
Marek Lindner3f4841f2013-04-23 21:40:00 +0800920 goto out;
921
Martin Hundebølld56b1702013-01-25 11:12:39 +0100922 /* accept ogms from 'good' neighbors and single hop neighbors */
923 if (!batadv_can_nc_with_orig(bat_priv, orig_node, ogm_packet) &&
924 !is_single_hop_neigh)
925 goto out;
926
927 /* Add orig_node as in_nc_node on hop */
928 in_nc_node = batadv_nc_get_nc_node(bat_priv, orig_node,
929 orig_neigh_node, true);
930 if (!in_nc_node)
931 goto out;
932
933 in_nc_node->last_seen = jiffies;
934
935 /* Add hop as out_nc_node on orig_node */
936 out_nc_node = batadv_nc_get_nc_node(bat_priv, orig_neigh_node,
937 orig_node, false);
938 if (!out_nc_node)
939 goto out;
940
941 out_nc_node->last_seen = jiffies;
942
943out:
944 if (in_nc_node)
945 batadv_nc_node_free_ref(in_nc_node);
946 if (out_nc_node)
947 batadv_nc_node_free_ref(out_nc_node);
948}
949
950/**
Martin Hundebøll95332472013-01-25 11:12:40 +0100951 * batadv_nc_get_path - get existing nc_path or allocate a new one
952 * @bat_priv: the bat priv with all the soft interface information
953 * @hash: hash table containing the nc path
954 * @src: ethernet source address - first half of the nc path search key
955 * @dst: ethernet destination address - second half of the nc path search key
956 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +0200957 * Return: pointer to nc_path if the path was found or created, returns NULL
Martin Hundebøll95332472013-01-25 11:12:40 +0100958 * on error.
959 */
960static struct batadv_nc_path *batadv_nc_get_path(struct batadv_priv *bat_priv,
961 struct batadv_hashtable *hash,
Sven Eckelmann6b5e9712015-05-26 18:34:26 +0200962 u8 *src,
963 u8 *dst)
Martin Hundebøll95332472013-01-25 11:12:40 +0100964{
965 int hash_added;
966 struct batadv_nc_path *nc_path, nc_path_key;
967
968 batadv_nc_hash_key_gen(&nc_path_key, src, dst);
969
970 /* Search for existing nc_path */
971 nc_path = batadv_nc_hash_find(hash, (void *)&nc_path_key);
972
973 if (nc_path) {
974 /* Set timestamp to delay removal of nc_path */
975 nc_path->last_valid = jiffies;
976 return nc_path;
977 }
978
979 /* No existing nc_path was found; create a new */
980 nc_path = kzalloc(sizeof(*nc_path), GFP_ATOMIC);
981
982 if (!nc_path)
983 return NULL;
984
985 /* Initialize nc_path */
986 INIT_LIST_HEAD(&nc_path->packet_list);
987 spin_lock_init(&nc_path->packet_list_lock);
Sven Eckelmann727e0cd2016-01-16 10:29:46 +0100988 kref_init(&nc_path->refcount);
989 kref_get(&nc_path->refcount);
Martin Hundebøll95332472013-01-25 11:12:40 +0100990 nc_path->last_valid = jiffies;
Antonio Quartulli8fdd0152014-01-22 00:42:11 +0100991 ether_addr_copy(nc_path->next_hop, dst);
992 ether_addr_copy(nc_path->prev_hop, src);
Martin Hundebøll95332472013-01-25 11:12:40 +0100993
994 batadv_dbg(BATADV_DBG_NC, bat_priv, "Adding nc_path %pM -> %pM\n",
995 nc_path->prev_hop,
996 nc_path->next_hop);
997
998 /* Add nc_path to hash table */
999 hash_added = batadv_hash_add(hash, batadv_nc_hash_compare,
1000 batadv_nc_hash_choose, &nc_path_key,
1001 &nc_path->hash_entry);
1002
1003 if (hash_added < 0) {
1004 kfree(nc_path);
1005 return NULL;
1006 }
1007
1008 return nc_path;
1009}
1010
1011/**
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001012 * batadv_nc_random_weight_tq - scale the receivers TQ-value to avoid unfair
1013 * selection of a receiver with slightly lower TQ than the other
1014 * @tq: to be weighted tq value
Sven Eckelmann672e7972015-10-31 12:29:30 +01001015 *
1016 * Return: scaled tq value
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001017 */
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001018static u8 batadv_nc_random_weight_tq(u8 tq)
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001019{
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001020 u8 rand_val, rand_tq;
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001021
1022 get_random_bytes(&rand_val, sizeof(rand_val));
1023
1024 /* randomize the estimated packet loss (max TQ - estimated TQ) */
1025 rand_tq = rand_val * (BATADV_TQ_MAX_VALUE - tq);
1026
1027 /* normalize the randomized packet loss */
1028 rand_tq /= BATADV_TQ_MAX_VALUE;
1029
1030 /* convert to (randomized) estimated tq again */
1031 return BATADV_TQ_MAX_VALUE - rand_tq;
1032}
1033
1034/**
1035 * batadv_nc_memxor - XOR destination with source
1036 * @dst: byte array to XOR into
1037 * @src: byte array to XOR from
1038 * @len: length of destination array
1039 */
1040static void batadv_nc_memxor(char *dst, const char *src, unsigned int len)
1041{
1042 unsigned int i;
1043
1044 for (i = 0; i < len; ++i)
1045 dst[i] ^= src[i];
1046}
1047
1048/**
1049 * batadv_nc_code_packets - code a received unicast_packet with an nc packet
1050 * into a coded_packet and send it
1051 * @bat_priv: the bat priv with all the soft interface information
1052 * @skb: data skb to forward
1053 * @ethhdr: pointer to the ethernet header inside the skb
1054 * @nc_packet: structure containing the packet to the skb can be coded with
1055 * @neigh_node: next hop to forward packet to
1056 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +02001057 * Return: true if both packets are consumed, false otherwise.
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001058 */
1059static bool batadv_nc_code_packets(struct batadv_priv *bat_priv,
1060 struct sk_buff *skb,
1061 struct ethhdr *ethhdr,
1062 struct batadv_nc_packet *nc_packet,
1063 struct batadv_neigh_node *neigh_node)
1064{
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001065 u8 tq_weighted_neigh, tq_weighted_coding, tq_tmp;
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001066 struct sk_buff *skb_dest, *skb_src;
1067 struct batadv_unicast_packet *packet1;
1068 struct batadv_unicast_packet *packet2;
1069 struct batadv_coded_packet *coded_packet;
1070 struct batadv_neigh_node *neigh_tmp, *router_neigh;
1071 struct batadv_neigh_node *router_coding = NULL;
Simon Wunderlich89652332013-11-13 19:14:46 +01001072 struct batadv_neigh_ifinfo *router_neigh_ifinfo = NULL;
1073 struct batadv_neigh_ifinfo *router_coding_ifinfo = NULL;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001074 u8 *first_source, *first_dest, *second_source, *second_dest;
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001075 __be32 packet_id1, packet_id2;
1076 size_t count;
1077 bool res = false;
1078 int coding_len;
1079 int unicast_size = sizeof(*packet1);
1080 int coded_size = sizeof(*coded_packet);
1081 int header_add = coded_size - unicast_size;
1082
Simon Wunderlich7351a4822013-11-13 19:14:47 +01001083 /* TODO: do we need to consider the outgoing interface for
1084 * coded packets?
1085 */
1086 router_neigh = batadv_orig_router_get(neigh_node->orig_node,
1087 BATADV_IF_DEFAULT);
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001088 if (!router_neigh)
1089 goto out;
1090
Simon Wunderlich89652332013-11-13 19:14:46 +01001091 router_neigh_ifinfo = batadv_neigh_ifinfo_get(router_neigh,
1092 BATADV_IF_DEFAULT);
1093 if (!router_neigh_ifinfo)
1094 goto out;
1095
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001096 neigh_tmp = nc_packet->neigh_node;
Simon Wunderlich7351a4822013-11-13 19:14:47 +01001097 router_coding = batadv_orig_router_get(neigh_tmp->orig_node,
1098 BATADV_IF_DEFAULT);
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001099 if (!router_coding)
1100 goto out;
1101
Simon Wunderlich89652332013-11-13 19:14:46 +01001102 router_coding_ifinfo = batadv_neigh_ifinfo_get(router_coding,
1103 BATADV_IF_DEFAULT);
1104 if (!router_coding_ifinfo)
1105 goto out;
1106
1107 tq_tmp = router_neigh_ifinfo->bat_iv.tq_avg;
1108 tq_weighted_neigh = batadv_nc_random_weight_tq(tq_tmp);
1109 tq_tmp = router_coding_ifinfo->bat_iv.tq_avg;
1110 tq_weighted_coding = batadv_nc_random_weight_tq(tq_tmp);
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001111
1112 /* Select one destination for the MAC-header dst-field based on
1113 * weighted TQ-values.
1114 */
1115 if (tq_weighted_neigh >= tq_weighted_coding) {
1116 /* Destination from nc_packet is selected for MAC-header */
1117 first_dest = nc_packet->nc_path->next_hop;
1118 first_source = nc_packet->nc_path->prev_hop;
1119 second_dest = neigh_node->addr;
1120 second_source = ethhdr->h_source;
1121 packet1 = (struct batadv_unicast_packet *)nc_packet->skb->data;
1122 packet2 = (struct batadv_unicast_packet *)skb->data;
1123 packet_id1 = nc_packet->packet_id;
1124 packet_id2 = batadv_skb_crc32(skb,
1125 skb->data + sizeof(*packet2));
1126 } else {
1127 /* Destination for skb is selected for MAC-header */
1128 first_dest = neigh_node->addr;
1129 first_source = ethhdr->h_source;
1130 second_dest = nc_packet->nc_path->next_hop;
1131 second_source = nc_packet->nc_path->prev_hop;
1132 packet1 = (struct batadv_unicast_packet *)skb->data;
1133 packet2 = (struct batadv_unicast_packet *)nc_packet->skb->data;
1134 packet_id1 = batadv_skb_crc32(skb,
1135 skb->data + sizeof(*packet1));
1136 packet_id2 = nc_packet->packet_id;
1137 }
1138
1139 /* Instead of zero padding the smallest data buffer, we
1140 * code into the largest.
1141 */
1142 if (skb->len <= nc_packet->skb->len) {
1143 skb_dest = nc_packet->skb;
1144 skb_src = skb;
1145 } else {
1146 skb_dest = skb;
1147 skb_src = nc_packet->skb;
1148 }
1149
1150 /* coding_len is used when decoding the packet shorter packet */
1151 coding_len = skb_src->len - unicast_size;
1152
1153 if (skb_linearize(skb_dest) < 0 || skb_linearize(skb_src) < 0)
1154 goto out;
1155
1156 skb_push(skb_dest, header_add);
1157
1158 coded_packet = (struct batadv_coded_packet *)skb_dest->data;
1159 skb_reset_mac_header(skb_dest);
1160
Simon Wunderlicha40d9b02013-12-02 20:38:31 +01001161 coded_packet->packet_type = BATADV_CODED;
1162 coded_packet->version = BATADV_COMPAT_VERSION;
1163 coded_packet->ttl = packet1->ttl;
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001164
1165 /* Info about first unicast packet */
Antonio Quartulli8fdd0152014-01-22 00:42:11 +01001166 ether_addr_copy(coded_packet->first_source, first_source);
1167 ether_addr_copy(coded_packet->first_orig_dest, packet1->dest);
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001168 coded_packet->first_crc = packet_id1;
1169 coded_packet->first_ttvn = packet1->ttvn;
1170
1171 /* Info about second unicast packet */
Antonio Quartulli8fdd0152014-01-22 00:42:11 +01001172 ether_addr_copy(coded_packet->second_dest, second_dest);
1173 ether_addr_copy(coded_packet->second_source, second_source);
1174 ether_addr_copy(coded_packet->second_orig_dest, packet2->dest);
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001175 coded_packet->second_crc = packet_id2;
Simon Wunderlicha40d9b02013-12-02 20:38:31 +01001176 coded_packet->second_ttl = packet2->ttl;
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001177 coded_packet->second_ttvn = packet2->ttvn;
1178 coded_packet->coded_len = htons(coding_len);
1179
1180 /* This is where the magic happens: Code skb_src into skb_dest */
1181 batadv_nc_memxor(skb_dest->data + coded_size,
1182 skb_src->data + unicast_size, coding_len);
1183
1184 /* Update counters accordingly */
1185 if (BATADV_SKB_CB(skb_src)->decoded &&
1186 BATADV_SKB_CB(skb_dest)->decoded) {
1187 /* Both packets are recoded */
1188 count = skb_src->len + ETH_HLEN;
1189 count += skb_dest->len + ETH_HLEN;
1190 batadv_add_counter(bat_priv, BATADV_CNT_NC_RECODE, 2);
1191 batadv_add_counter(bat_priv, BATADV_CNT_NC_RECODE_BYTES, count);
1192 } else if (!BATADV_SKB_CB(skb_src)->decoded &&
1193 !BATADV_SKB_CB(skb_dest)->decoded) {
1194 /* Both packets are newly coded */
1195 count = skb_src->len + ETH_HLEN;
1196 count += skb_dest->len + ETH_HLEN;
1197 batadv_add_counter(bat_priv, BATADV_CNT_NC_CODE, 2);
1198 batadv_add_counter(bat_priv, BATADV_CNT_NC_CODE_BYTES, count);
1199 } else if (BATADV_SKB_CB(skb_src)->decoded &&
1200 !BATADV_SKB_CB(skb_dest)->decoded) {
1201 /* skb_src recoded and skb_dest is newly coded */
1202 batadv_inc_counter(bat_priv, BATADV_CNT_NC_RECODE);
1203 batadv_add_counter(bat_priv, BATADV_CNT_NC_RECODE_BYTES,
1204 skb_src->len + ETH_HLEN);
1205 batadv_inc_counter(bat_priv, BATADV_CNT_NC_CODE);
1206 batadv_add_counter(bat_priv, BATADV_CNT_NC_CODE_BYTES,
1207 skb_dest->len + ETH_HLEN);
1208 } else if (!BATADV_SKB_CB(skb_src)->decoded &&
1209 BATADV_SKB_CB(skb_dest)->decoded) {
1210 /* skb_src is newly coded and skb_dest is recoded */
1211 batadv_inc_counter(bat_priv, BATADV_CNT_NC_CODE);
1212 batadv_add_counter(bat_priv, BATADV_CNT_NC_CODE_BYTES,
1213 skb_src->len + ETH_HLEN);
1214 batadv_inc_counter(bat_priv, BATADV_CNT_NC_RECODE);
1215 batadv_add_counter(bat_priv, BATADV_CNT_NC_RECODE_BYTES,
1216 skb_dest->len + ETH_HLEN);
1217 }
1218
1219 /* skb_src is now coded into skb_dest, so free it */
1220 kfree_skb(skb_src);
1221
1222 /* avoid duplicate free of skb from nc_packet */
1223 nc_packet->skb = NULL;
1224 batadv_nc_packet_free(nc_packet);
1225
1226 /* Send the coded packet and return true */
1227 batadv_send_skb_packet(skb_dest, neigh_node->if_incoming, first_dest);
1228 res = true;
1229out:
1230 if (router_neigh)
1231 batadv_neigh_node_free_ref(router_neigh);
1232 if (router_coding)
1233 batadv_neigh_node_free_ref(router_coding);
Simon Wunderlich89652332013-11-13 19:14:46 +01001234 if (router_neigh_ifinfo)
1235 batadv_neigh_ifinfo_free_ref(router_neigh_ifinfo);
1236 if (router_coding_ifinfo)
1237 batadv_neigh_ifinfo_free_ref(router_coding_ifinfo);
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001238 return res;
1239}
1240
1241/**
1242 * batadv_nc_skb_coding_possible - true if a decoded skb is available at dst.
1243 * @skb: data skb to forward
1244 * @dst: destination mac address of the other skb to code with
1245 * @src: source mac address of skb
1246 *
1247 * Whenever we network code a packet we have to check whether we received it in
1248 * a network coded form. If so, we may not be able to use it for coding because
1249 * some neighbors may also have received (overheard) the packet in the network
1250 * coded form without being able to decode it. It is hard to know which of the
1251 * neighboring nodes was able to decode the packet, therefore we can only
1252 * re-code the packet if the source of the previous encoded packet is involved.
1253 * Since the source encoded the packet we can be certain it has all necessary
1254 * decode information.
1255 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +02001256 * Return: true if coding of a decoded packet is allowed.
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001257 */
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001258static bool batadv_nc_skb_coding_possible(struct sk_buff *skb, u8 *dst, u8 *src)
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001259{
1260 if (BATADV_SKB_CB(skb)->decoded && !batadv_compare_eth(dst, src))
1261 return false;
Antonio Quartulli24820df2014-09-01 14:37:25 +02001262 return true;
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001263}
1264
1265/**
1266 * batadv_nc_path_search - Find the coding path matching in_nc_node and
1267 * out_nc_node to retrieve a buffered packet that can be used for coding.
1268 * @bat_priv: the bat priv with all the soft interface information
1269 * @in_nc_node: pointer to skb next hop's neighbor nc node
1270 * @out_nc_node: pointer to skb source's neighbor nc node
1271 * @skb: data skb to forward
1272 * @eth_dst: next hop mac address of skb
1273 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +02001274 * Return: true if coding of a decoded skb is allowed.
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001275 */
1276static struct batadv_nc_packet *
1277batadv_nc_path_search(struct batadv_priv *bat_priv,
1278 struct batadv_nc_node *in_nc_node,
1279 struct batadv_nc_node *out_nc_node,
1280 struct sk_buff *skb,
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001281 u8 *eth_dst)
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001282{
1283 struct batadv_nc_path *nc_path, nc_path_key;
1284 struct batadv_nc_packet *nc_packet_out = NULL;
1285 struct batadv_nc_packet *nc_packet, *nc_packet_tmp;
1286 struct batadv_hashtable *hash = bat_priv->nc.coding_hash;
1287 int idx;
1288
1289 if (!hash)
1290 return NULL;
1291
1292 /* Create almost path key */
1293 batadv_nc_hash_key_gen(&nc_path_key, in_nc_node->addr,
1294 out_nc_node->addr);
1295 idx = batadv_nc_hash_choose(&nc_path_key, hash->size);
1296
1297 /* Check for coding opportunities in this nc_path */
1298 rcu_read_lock();
1299 hlist_for_each_entry_rcu(nc_path, &hash->table[idx], hash_entry) {
1300 if (!batadv_compare_eth(nc_path->prev_hop, in_nc_node->addr))
1301 continue;
1302
1303 if (!batadv_compare_eth(nc_path->next_hop, out_nc_node->addr))
1304 continue;
1305
1306 spin_lock_bh(&nc_path->packet_list_lock);
1307 if (list_empty(&nc_path->packet_list)) {
1308 spin_unlock_bh(&nc_path->packet_list_lock);
1309 continue;
1310 }
1311
1312 list_for_each_entry_safe(nc_packet, nc_packet_tmp,
1313 &nc_path->packet_list, list) {
1314 if (!batadv_nc_skb_coding_possible(nc_packet->skb,
1315 eth_dst,
1316 in_nc_node->addr))
1317 continue;
1318
1319 /* Coding opportunity is found! */
1320 list_del(&nc_packet->list);
1321 nc_packet_out = nc_packet;
1322 break;
1323 }
1324
1325 spin_unlock_bh(&nc_path->packet_list_lock);
1326 break;
1327 }
1328 rcu_read_unlock();
1329
1330 return nc_packet_out;
1331}
1332
1333/**
1334 * batadv_nc_skb_src_search - Loops through the list of neighoring nodes of the
1335 * skb's sender (may be equal to the originator).
1336 * @bat_priv: the bat priv with all the soft interface information
1337 * @skb: data skb to forward
1338 * @eth_dst: next hop mac address of skb
1339 * @eth_src: source mac address of skb
1340 * @in_nc_node: pointer to skb next hop's neighbor nc node
1341 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +02001342 * Return: an nc packet if a suitable coding packet was found, NULL otherwise.
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001343 */
1344static struct batadv_nc_packet *
1345batadv_nc_skb_src_search(struct batadv_priv *bat_priv,
1346 struct sk_buff *skb,
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001347 u8 *eth_dst,
1348 u8 *eth_src,
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001349 struct batadv_nc_node *in_nc_node)
1350{
1351 struct batadv_orig_node *orig_node;
1352 struct batadv_nc_node *out_nc_node;
1353 struct batadv_nc_packet *nc_packet = NULL;
1354
1355 orig_node = batadv_orig_hash_find(bat_priv, eth_src);
1356 if (!orig_node)
1357 return NULL;
1358
1359 rcu_read_lock();
1360 list_for_each_entry_rcu(out_nc_node,
1361 &orig_node->out_coding_list, list) {
1362 /* Check if the skb is decoded and if recoding is possible */
1363 if (!batadv_nc_skb_coding_possible(skb,
1364 out_nc_node->addr, eth_src))
1365 continue;
1366
1367 /* Search for an opportunity in this nc_path */
1368 nc_packet = batadv_nc_path_search(bat_priv, in_nc_node,
1369 out_nc_node, skb, eth_dst);
1370 if (nc_packet)
1371 break;
1372 }
1373 rcu_read_unlock();
1374
1375 batadv_orig_node_free_ref(orig_node);
1376 return nc_packet;
1377}
1378
1379/**
Martin Hundebøll612d2b42013-01-25 11:12:42 +01001380 * batadv_nc_skb_store_before_coding - set the ethernet src and dst of the
1381 * unicast skb before it is stored for use in later decoding
1382 * @bat_priv: the bat priv with all the soft interface information
1383 * @skb: data skb to store
1384 * @eth_dst_new: new destination mac address of skb
1385 */
1386static void batadv_nc_skb_store_before_coding(struct batadv_priv *bat_priv,
1387 struct sk_buff *skb,
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001388 u8 *eth_dst_new)
Martin Hundebøll612d2b42013-01-25 11:12:42 +01001389{
1390 struct ethhdr *ethhdr;
1391
1392 /* Copy skb header to change the mac header */
Octavian Purdilabad93e92014-06-12 01:36:26 +03001393 skb = pskb_copy_for_clone(skb, GFP_ATOMIC);
Martin Hundebøll612d2b42013-01-25 11:12:42 +01001394 if (!skb)
1395 return;
1396
1397 /* Set the mac header as if we actually sent the packet uncoded */
Antonio Quartulli7ed4be92013-04-08 15:08:18 +02001398 ethhdr = eth_hdr(skb);
Antonio Quartulli8fdd0152014-01-22 00:42:11 +01001399 ether_addr_copy(ethhdr->h_source, ethhdr->h_dest);
1400 ether_addr_copy(ethhdr->h_dest, eth_dst_new);
Martin Hundebøll612d2b42013-01-25 11:12:42 +01001401
1402 /* Set data pointer to MAC header to mimic packets from our tx path */
1403 skb_push(skb, ETH_HLEN);
1404
1405 /* Add the packet to the decoding packet pool */
1406 batadv_nc_skb_store_for_decoding(bat_priv, skb);
1407
1408 /* batadv_nc_skb_store_for_decoding() clones the skb, so we must free
1409 * our ref
1410 */
1411 kfree_skb(skb);
1412}
1413
1414/**
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001415 * batadv_nc_skb_dst_search - Loops through list of neighboring nodes to dst.
1416 * @skb: data skb to forward
1417 * @neigh_node: next hop to forward packet to
1418 * @ethhdr: pointer to the ethernet header inside the skb
1419 *
1420 * Loops through list of neighboring nodes the next hop has a good connection to
1421 * (receives OGMs with a sufficient quality). We need to find a neighbor of our
1422 * next hop that potentially sent a packet which our next hop also received
1423 * (overheard) and has stored for later decoding.
1424 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +02001425 * Return: true if the skb was consumed (encoded packet sent) or false otherwise
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001426 */
1427static bool batadv_nc_skb_dst_search(struct sk_buff *skb,
1428 struct batadv_neigh_node *neigh_node,
1429 struct ethhdr *ethhdr)
1430{
1431 struct net_device *netdev = neigh_node->if_incoming->soft_iface;
1432 struct batadv_priv *bat_priv = netdev_priv(netdev);
1433 struct batadv_orig_node *orig_node = neigh_node->orig_node;
1434 struct batadv_nc_node *nc_node;
1435 struct batadv_nc_packet *nc_packet = NULL;
1436
1437 rcu_read_lock();
1438 list_for_each_entry_rcu(nc_node, &orig_node->in_coding_list, list) {
1439 /* Search for coding opportunity with this in_nc_node */
1440 nc_packet = batadv_nc_skb_src_search(bat_priv, skb,
1441 neigh_node->addr,
1442 ethhdr->h_source, nc_node);
1443
1444 /* Opportunity was found, so stop searching */
1445 if (nc_packet)
1446 break;
1447 }
1448 rcu_read_unlock();
1449
1450 if (!nc_packet)
1451 return false;
1452
Martin Hundebøll612d2b42013-01-25 11:12:42 +01001453 /* Save packets for later decoding */
1454 batadv_nc_skb_store_before_coding(bat_priv, skb,
1455 neigh_node->addr);
1456 batadv_nc_skb_store_before_coding(bat_priv, nc_packet->skb,
1457 nc_packet->neigh_node->addr);
1458
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001459 /* Code and send packets */
1460 if (batadv_nc_code_packets(bat_priv, skb, ethhdr, nc_packet,
1461 neigh_node))
1462 return true;
1463
1464 /* out of mem ? Coding failed - we have to free the buffered packet
1465 * to avoid memleaks. The skb passed as argument will be dealt with
1466 * by the calling function.
1467 */
1468 batadv_nc_send_packet(nc_packet);
1469 return false;
1470}
1471
1472/**
Martin Hundebøll95332472013-01-25 11:12:40 +01001473 * batadv_nc_skb_add_to_path - buffer skb for later encoding / decoding
1474 * @skb: skb to add to path
1475 * @nc_path: path to add skb to
1476 * @neigh_node: next hop to forward packet to
1477 * @packet_id: checksum to identify packet
1478 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +02001479 * Return: true if the packet was buffered or false in case of an error.
Martin Hundebøll95332472013-01-25 11:12:40 +01001480 */
1481static bool batadv_nc_skb_add_to_path(struct sk_buff *skb,
1482 struct batadv_nc_path *nc_path,
1483 struct batadv_neigh_node *neigh_node,
1484 __be32 packet_id)
1485{
1486 struct batadv_nc_packet *nc_packet;
1487
1488 nc_packet = kzalloc(sizeof(*nc_packet), GFP_ATOMIC);
1489 if (!nc_packet)
1490 return false;
1491
1492 /* Initialize nc_packet */
1493 nc_packet->timestamp = jiffies;
1494 nc_packet->packet_id = packet_id;
1495 nc_packet->skb = skb;
1496 nc_packet->neigh_node = neigh_node;
1497 nc_packet->nc_path = nc_path;
1498
1499 /* Add coding packet to list */
1500 spin_lock_bh(&nc_path->packet_list_lock);
1501 list_add_tail(&nc_packet->list, &nc_path->packet_list);
1502 spin_unlock_bh(&nc_path->packet_list_lock);
1503
1504 return true;
1505}
1506
1507/**
1508 * batadv_nc_skb_forward - try to code a packet or add it to the coding packet
1509 * buffer
1510 * @skb: data skb to forward
1511 * @neigh_node: next hop to forward packet to
Martin Hundebøll95332472013-01-25 11:12:40 +01001512 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +02001513 * Return: true if the skb was consumed (encoded packet sent) or false otherwise
Martin Hundebøll95332472013-01-25 11:12:40 +01001514 */
1515bool batadv_nc_skb_forward(struct sk_buff *skb,
Martin Hundebølle91ecfc2013-04-20 13:54:39 +02001516 struct batadv_neigh_node *neigh_node)
Martin Hundebøll95332472013-01-25 11:12:40 +01001517{
1518 const struct net_device *netdev = neigh_node->if_incoming->soft_iface;
1519 struct batadv_priv *bat_priv = netdev_priv(netdev);
1520 struct batadv_unicast_packet *packet;
1521 struct batadv_nc_path *nc_path;
Martin Hundebølle91ecfc2013-04-20 13:54:39 +02001522 struct ethhdr *ethhdr = eth_hdr(skb);
Martin Hundebøll95332472013-01-25 11:12:40 +01001523 __be32 packet_id;
1524 u8 *payload;
1525
1526 /* Check if network coding is enabled */
1527 if (!atomic_read(&bat_priv->network_coding))
1528 goto out;
1529
1530 /* We only handle unicast packets */
1531 payload = skb_network_header(skb);
1532 packet = (struct batadv_unicast_packet *)payload;
Simon Wunderlicha40d9b02013-12-02 20:38:31 +01001533 if (packet->packet_type != BATADV_UNICAST)
Martin Hundebøll95332472013-01-25 11:12:40 +01001534 goto out;
1535
Martin Hundebøll3c12de92013-01-25 11:12:41 +01001536 /* Try to find a coding opportunity and send the skb if one is found */
1537 if (batadv_nc_skb_dst_search(skb, neigh_node, ethhdr))
1538 return true;
1539
Martin Hundebøll95332472013-01-25 11:12:40 +01001540 /* Find or create a nc_path for this src-dst pair */
1541 nc_path = batadv_nc_get_path(bat_priv,
1542 bat_priv->nc.coding_hash,
1543 ethhdr->h_source,
1544 neigh_node->addr);
1545
1546 if (!nc_path)
1547 goto out;
1548
1549 /* Add skb to nc_path */
1550 packet_id = batadv_skb_crc32(skb, payload + sizeof(*packet));
1551 if (!batadv_nc_skb_add_to_path(skb, nc_path, neigh_node, packet_id))
1552 goto free_nc_path;
1553
1554 /* Packet is consumed */
1555 return true;
1556
1557free_nc_path:
1558 batadv_nc_path_free_ref(nc_path);
1559out:
1560 /* Packet is not consumed */
1561 return false;
1562}
1563
1564/**
Martin Hundebøll612d2b42013-01-25 11:12:42 +01001565 * batadv_nc_skb_store_for_decoding - save a clone of the skb which can be used
1566 * when decoding coded packets
1567 * @bat_priv: the bat priv with all the soft interface information
1568 * @skb: data skb to store
1569 */
1570void batadv_nc_skb_store_for_decoding(struct batadv_priv *bat_priv,
1571 struct sk_buff *skb)
1572{
1573 struct batadv_unicast_packet *packet;
1574 struct batadv_nc_path *nc_path;
Antonio Quartulli7ed4be92013-04-08 15:08:18 +02001575 struct ethhdr *ethhdr = eth_hdr(skb);
Martin Hundebøll612d2b42013-01-25 11:12:42 +01001576 __be32 packet_id;
1577 u8 *payload;
1578
1579 /* Check if network coding is enabled */
1580 if (!atomic_read(&bat_priv->network_coding))
1581 goto out;
1582
1583 /* Check for supported packet type */
1584 payload = skb_network_header(skb);
1585 packet = (struct batadv_unicast_packet *)payload;
Simon Wunderlicha40d9b02013-12-02 20:38:31 +01001586 if (packet->packet_type != BATADV_UNICAST)
Martin Hundebøll612d2b42013-01-25 11:12:42 +01001587 goto out;
1588
1589 /* Find existing nc_path or create a new */
1590 nc_path = batadv_nc_get_path(bat_priv,
1591 bat_priv->nc.decoding_hash,
1592 ethhdr->h_source,
1593 ethhdr->h_dest);
1594
1595 if (!nc_path)
1596 goto out;
1597
1598 /* Clone skb and adjust skb->data to point at batman header */
1599 skb = skb_clone(skb, GFP_ATOMIC);
1600 if (unlikely(!skb))
1601 goto free_nc_path;
1602
1603 if (unlikely(!pskb_may_pull(skb, ETH_HLEN)))
1604 goto free_skb;
1605
1606 if (unlikely(!skb_pull_rcsum(skb, ETH_HLEN)))
1607 goto free_skb;
1608
1609 /* Add skb to nc_path */
1610 packet_id = batadv_skb_crc32(skb, payload + sizeof(*packet));
1611 if (!batadv_nc_skb_add_to_path(skb, nc_path, NULL, packet_id))
1612 goto free_skb;
1613
1614 batadv_inc_counter(bat_priv, BATADV_CNT_NC_BUFFER);
1615 return;
1616
1617free_skb:
1618 kfree_skb(skb);
1619free_nc_path:
1620 batadv_nc_path_free_ref(nc_path);
1621out:
1622 return;
1623}
1624
1625/**
1626 * batadv_nc_skb_store_sniffed_unicast - check if a received unicast packet
1627 * should be saved in the decoding buffer and, if so, store it there
1628 * @bat_priv: the bat priv with all the soft interface information
1629 * @skb: unicast skb to store
1630 */
1631void batadv_nc_skb_store_sniffed_unicast(struct batadv_priv *bat_priv,
1632 struct sk_buff *skb)
1633{
Antonio Quartulli7ed4be92013-04-08 15:08:18 +02001634 struct ethhdr *ethhdr = eth_hdr(skb);
Martin Hundebøll612d2b42013-01-25 11:12:42 +01001635
David S. Miller6e0895c2013-04-22 20:32:51 -04001636 if (batadv_is_my_mac(bat_priv, ethhdr->h_dest))
Martin Hundebøll612d2b42013-01-25 11:12:42 +01001637 return;
1638
1639 /* Set data pointer to MAC header to mimic packets from our tx path */
1640 skb_push(skb, ETH_HLEN);
1641
1642 batadv_nc_skb_store_for_decoding(bat_priv, skb);
1643}
1644
1645/**
Martin Hundebøll2df52782013-01-25 11:12:43 +01001646 * batadv_nc_skb_decode_packet - decode given skb using the decode data stored
1647 * in nc_packet
David S. Miller6e0895c2013-04-22 20:32:51 -04001648 * @bat_priv: the bat priv with all the soft interface information
Martin Hundebøll2df52782013-01-25 11:12:43 +01001649 * @skb: unicast skb to decode
1650 * @nc_packet: decode data needed to decode the skb
1651 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +02001652 * Return: pointer to decoded unicast packet if the packet was decoded or NULL
Martin Hundebøll2df52782013-01-25 11:12:43 +01001653 * in case of an error.
1654 */
1655static struct batadv_unicast_packet *
David S. Miller6e0895c2013-04-22 20:32:51 -04001656batadv_nc_skb_decode_packet(struct batadv_priv *bat_priv, struct sk_buff *skb,
Martin Hundebøll2df52782013-01-25 11:12:43 +01001657 struct batadv_nc_packet *nc_packet)
1658{
1659 const int h_size = sizeof(struct batadv_unicast_packet);
1660 const int h_diff = sizeof(struct batadv_coded_packet) - h_size;
1661 struct batadv_unicast_packet *unicast_packet;
1662 struct batadv_coded_packet coded_packet_tmp;
1663 struct ethhdr *ethhdr, ethhdr_tmp;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001664 u8 *orig_dest, ttl, ttvn;
Martin Hundebøll2df52782013-01-25 11:12:43 +01001665 unsigned int coding_len;
Marek Lindner7da19972013-05-07 19:25:02 +08001666 int err;
Martin Hundebøll2df52782013-01-25 11:12:43 +01001667
1668 /* Save headers temporarily */
1669 memcpy(&coded_packet_tmp, skb->data, sizeof(coded_packet_tmp));
1670 memcpy(&ethhdr_tmp, skb_mac_header(skb), sizeof(ethhdr_tmp));
1671
1672 if (skb_cow(skb, 0) < 0)
1673 return NULL;
1674
1675 if (unlikely(!skb_pull_rcsum(skb, h_diff)))
1676 return NULL;
1677
1678 /* Data points to batman header, so set mac header 14 bytes before
1679 * and network to data
1680 */
1681 skb_set_mac_header(skb, -ETH_HLEN);
1682 skb_reset_network_header(skb);
1683
1684 /* Reconstruct original mac header */
Antonio Quartulli7ed4be92013-04-08 15:08:18 +02001685 ethhdr = eth_hdr(skb);
Fengguang Wuabae9472014-01-06 17:09:46 +01001686 *ethhdr = ethhdr_tmp;
Martin Hundebøll2df52782013-01-25 11:12:43 +01001687
1688 /* Select the correct unicast header information based on the location
1689 * of our mac address in the coded_packet header
1690 */
David S. Miller6e0895c2013-04-22 20:32:51 -04001691 if (batadv_is_my_mac(bat_priv, coded_packet_tmp.second_dest)) {
Martin Hundebøll2df52782013-01-25 11:12:43 +01001692 /* If we are the second destination the packet was overheard,
1693 * so the Ethernet address must be copied to h_dest and
1694 * pkt_type changed from PACKET_OTHERHOST to PACKET_HOST
1695 */
Antonio Quartulli8fdd0152014-01-22 00:42:11 +01001696 ether_addr_copy(ethhdr->h_dest, coded_packet_tmp.second_dest);
Martin Hundebøll2df52782013-01-25 11:12:43 +01001697 skb->pkt_type = PACKET_HOST;
1698
1699 orig_dest = coded_packet_tmp.second_orig_dest;
1700 ttl = coded_packet_tmp.second_ttl;
1701 ttvn = coded_packet_tmp.second_ttvn;
1702 } else {
1703 orig_dest = coded_packet_tmp.first_orig_dest;
Simon Wunderlicha40d9b02013-12-02 20:38:31 +01001704 ttl = coded_packet_tmp.ttl;
Martin Hundebøll2df52782013-01-25 11:12:43 +01001705 ttvn = coded_packet_tmp.first_ttvn;
1706 }
1707
1708 coding_len = ntohs(coded_packet_tmp.coded_len);
1709
1710 if (coding_len > skb->len)
1711 return NULL;
1712
1713 /* Here the magic is reversed:
1714 * extract the missing packet from the received coded packet
1715 */
1716 batadv_nc_memxor(skb->data + h_size,
1717 nc_packet->skb->data + h_size,
1718 coding_len);
1719
1720 /* Resize decoded skb if decoded with larger packet */
Marek Lindner7da19972013-05-07 19:25:02 +08001721 if (nc_packet->skb->len > coding_len + h_size) {
1722 err = pskb_trim_rcsum(skb, coding_len + h_size);
1723 if (err)
1724 return NULL;
1725 }
Martin Hundebøll2df52782013-01-25 11:12:43 +01001726
1727 /* Create decoded unicast packet */
1728 unicast_packet = (struct batadv_unicast_packet *)skb->data;
Simon Wunderlicha40d9b02013-12-02 20:38:31 +01001729 unicast_packet->packet_type = BATADV_UNICAST;
1730 unicast_packet->version = BATADV_COMPAT_VERSION;
1731 unicast_packet->ttl = ttl;
Antonio Quartulli8fdd0152014-01-22 00:42:11 +01001732 ether_addr_copy(unicast_packet->dest, orig_dest);
Martin Hundebøll2df52782013-01-25 11:12:43 +01001733 unicast_packet->ttvn = ttvn;
1734
1735 batadv_nc_packet_free(nc_packet);
1736 return unicast_packet;
1737}
1738
1739/**
1740 * batadv_nc_find_decoding_packet - search through buffered decoding data to
1741 * find the data needed to decode the coded packet
1742 * @bat_priv: the bat priv with all the soft interface information
1743 * @ethhdr: pointer to the ethernet header inside the coded packet
1744 * @coded: coded packet we try to find decode data for
1745 *
Sven Eckelmann62fe7102015-09-15 19:00:48 +02001746 * Return: pointer to nc packet if the needed data was found or NULL otherwise.
Martin Hundebøll2df52782013-01-25 11:12:43 +01001747 */
1748static struct batadv_nc_packet *
1749batadv_nc_find_decoding_packet(struct batadv_priv *bat_priv,
1750 struct ethhdr *ethhdr,
1751 struct batadv_coded_packet *coded)
1752{
1753 struct batadv_hashtable *hash = bat_priv->nc.decoding_hash;
1754 struct batadv_nc_packet *tmp_nc_packet, *nc_packet = NULL;
1755 struct batadv_nc_path *nc_path, nc_path_key;
Sven Eckelmann6b5e9712015-05-26 18:34:26 +02001756 u8 *dest, *source;
Martin Hundebøll2df52782013-01-25 11:12:43 +01001757 __be32 packet_id;
1758 int index;
1759
1760 if (!hash)
1761 return NULL;
1762
1763 /* Select the correct packet id based on the location of our mac-addr */
1764 dest = ethhdr->h_source;
David S. Miller6e0895c2013-04-22 20:32:51 -04001765 if (!batadv_is_my_mac(bat_priv, coded->second_dest)) {
Martin Hundebøll2df52782013-01-25 11:12:43 +01001766 source = coded->second_source;
1767 packet_id = coded->second_crc;
1768 } else {
1769 source = coded->first_source;
1770 packet_id = coded->first_crc;
1771 }
1772
1773 batadv_nc_hash_key_gen(&nc_path_key, source, dest);
1774 index = batadv_nc_hash_choose(&nc_path_key, hash->size);
1775
1776 /* Search for matching coding path */
1777 rcu_read_lock();
1778 hlist_for_each_entry_rcu(nc_path, &hash->table[index], hash_entry) {
1779 /* Find matching nc_packet */
1780 spin_lock_bh(&nc_path->packet_list_lock);
1781 list_for_each_entry(tmp_nc_packet,
1782 &nc_path->packet_list, list) {
1783 if (packet_id == tmp_nc_packet->packet_id) {
1784 list_del(&tmp_nc_packet->list);
1785
1786 nc_packet = tmp_nc_packet;
1787 break;
1788 }
1789 }
1790 spin_unlock_bh(&nc_path->packet_list_lock);
1791
1792 if (nc_packet)
1793 break;
1794 }
1795 rcu_read_unlock();
1796
1797 if (!nc_packet)
1798 batadv_dbg(BATADV_DBG_NC, bat_priv,
1799 "No decoding packet found for %u\n", packet_id);
1800
1801 return nc_packet;
1802}
1803
1804/**
1805 * batadv_nc_recv_coded_packet - try to decode coded packet and enqueue the
1806 * resulting unicast packet
1807 * @skb: incoming coded packet
1808 * @recv_if: pointer to interface this packet was received on
Sven Eckelmann672e7972015-10-31 12:29:30 +01001809 *
1810 * Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP
1811 * otherwise.
Martin Hundebøll2df52782013-01-25 11:12:43 +01001812 */
1813static int batadv_nc_recv_coded_packet(struct sk_buff *skb,
1814 struct batadv_hard_iface *recv_if)
1815{
1816 struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1817 struct batadv_unicast_packet *unicast_packet;
1818 struct batadv_coded_packet *coded_packet;
1819 struct batadv_nc_packet *nc_packet;
1820 struct ethhdr *ethhdr;
1821 int hdr_size = sizeof(*coded_packet);
1822
1823 /* Check if network coding is enabled */
1824 if (!atomic_read(&bat_priv->network_coding))
1825 return NET_RX_DROP;
1826
1827 /* Make sure we can access (and remove) header */
1828 if (unlikely(!pskb_may_pull(skb, hdr_size)))
1829 return NET_RX_DROP;
1830
1831 coded_packet = (struct batadv_coded_packet *)skb->data;
Antonio Quartulli7ed4be92013-04-08 15:08:18 +02001832 ethhdr = eth_hdr(skb);
Martin Hundebøll2df52782013-01-25 11:12:43 +01001833
1834 /* Verify frame is destined for us */
David S. Miller6e0895c2013-04-22 20:32:51 -04001835 if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest) &&
1836 !batadv_is_my_mac(bat_priv, coded_packet->second_dest))
Martin Hundebøll2df52782013-01-25 11:12:43 +01001837 return NET_RX_DROP;
1838
1839 /* Update stat counter */
David S. Miller6e0895c2013-04-22 20:32:51 -04001840 if (batadv_is_my_mac(bat_priv, coded_packet->second_dest))
Martin Hundebøll2df52782013-01-25 11:12:43 +01001841 batadv_inc_counter(bat_priv, BATADV_CNT_NC_SNIFFED);
1842
1843 nc_packet = batadv_nc_find_decoding_packet(bat_priv, ethhdr,
1844 coded_packet);
1845 if (!nc_packet) {
1846 batadv_inc_counter(bat_priv, BATADV_CNT_NC_DECODE_FAILED);
1847 return NET_RX_DROP;
1848 }
1849
1850 /* Make skb's linear, because decoding accesses the entire buffer */
1851 if (skb_linearize(skb) < 0)
1852 goto free_nc_packet;
1853
1854 if (skb_linearize(nc_packet->skb) < 0)
1855 goto free_nc_packet;
1856
1857 /* Decode the packet */
David S. Miller6e0895c2013-04-22 20:32:51 -04001858 unicast_packet = batadv_nc_skb_decode_packet(bat_priv, skb, nc_packet);
Martin Hundebøll2df52782013-01-25 11:12:43 +01001859 if (!unicast_packet) {
1860 batadv_inc_counter(bat_priv, BATADV_CNT_NC_DECODE_FAILED);
1861 goto free_nc_packet;
1862 }
1863
1864 /* Mark packet as decoded to do correct recoding when forwarding */
1865 BATADV_SKB_CB(skb)->decoded = true;
1866 batadv_inc_counter(bat_priv, BATADV_CNT_NC_DECODE);
1867 batadv_add_counter(bat_priv, BATADV_CNT_NC_DECODE_BYTES,
1868 skb->len + ETH_HLEN);
1869 return batadv_recv_unicast_packet(skb, recv_if);
1870
1871free_nc_packet:
1872 batadv_nc_packet_free(nc_packet);
1873 return NET_RX_DROP;
1874}
1875
1876/**
Matthias Schiffer6c519ba2013-09-27 18:03:39 +02001877 * batadv_nc_mesh_free - clean up network coding memory
Martin Hundebølld353d8d2013-01-25 11:12:38 +01001878 * @bat_priv: the bat priv with all the soft interface information
1879 */
Matthias Schiffer6c519ba2013-09-27 18:03:39 +02001880void batadv_nc_mesh_free(struct batadv_priv *bat_priv)
Martin Hundebølld353d8d2013-01-25 11:12:38 +01001881{
Marek Lindner3f4841f2013-04-23 21:40:00 +08001882 batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_NC, 1);
1883 batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_NC, 1);
Martin Hundebølld353d8d2013-01-25 11:12:38 +01001884 cancel_delayed_work_sync(&bat_priv->nc.work);
Martin Hundebøll612d2b42013-01-25 11:12:42 +01001885
Martin Hundebøll95332472013-01-25 11:12:40 +01001886 batadv_nc_purge_paths(bat_priv, bat_priv->nc.coding_hash, NULL);
1887 batadv_hash_destroy(bat_priv->nc.coding_hash);
Martin Hundebøll612d2b42013-01-25 11:12:42 +01001888 batadv_nc_purge_paths(bat_priv, bat_priv->nc.decoding_hash, NULL);
1889 batadv_hash_destroy(bat_priv->nc.decoding_hash);
Martin Hundebølld353d8d2013-01-25 11:12:38 +01001890}
Martin Hundebølld56b1702013-01-25 11:12:39 +01001891
1892/**
1893 * batadv_nc_nodes_seq_print_text - print the nc node information
1894 * @seq: seq file to print on
1895 * @offset: not used
Sven Eckelmann672e7972015-10-31 12:29:30 +01001896 *
1897 * Return: always 0
Martin Hundebølld56b1702013-01-25 11:12:39 +01001898 */
1899int batadv_nc_nodes_seq_print_text(struct seq_file *seq, void *offset)
1900{
1901 struct net_device *net_dev = (struct net_device *)seq->private;
1902 struct batadv_priv *bat_priv = netdev_priv(net_dev);
1903 struct batadv_hashtable *hash = bat_priv->orig_hash;
1904 struct batadv_hard_iface *primary_if;
1905 struct hlist_head *head;
1906 struct batadv_orig_node *orig_node;
1907 struct batadv_nc_node *nc_node;
1908 int i;
1909
1910 primary_if = batadv_seq_print_text_primary_if_get(seq);
1911 if (!primary_if)
1912 goto out;
1913
1914 /* Traverse list of originators */
1915 for (i = 0; i < hash->size; i++) {
1916 head = &hash->table[i];
1917
1918 /* For each orig_node in this bin */
1919 rcu_read_lock();
1920 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
Marek Lindneraa27c3122013-04-18 04:56:03 +08001921 /* no need to print the orig node if it does not have
1922 * network coding neighbors
1923 */
1924 if (list_empty(&orig_node->in_coding_list) &&
1925 list_empty(&orig_node->out_coding_list))
1926 continue;
1927
Martin Hundebølld56b1702013-01-25 11:12:39 +01001928 seq_printf(seq, "Node: %pM\n", orig_node->orig);
1929
Antonio Quartulli0c814652013-03-21 09:23:29 +01001930 seq_puts(seq, " Ingoing: ");
Martin Hundebølld56b1702013-01-25 11:12:39 +01001931 /* For each in_nc_node to this orig_node */
1932 list_for_each_entry_rcu(nc_node,
1933 &orig_node->in_coding_list,
1934 list)
1935 seq_printf(seq, "%pM ",
1936 nc_node->addr);
Antonio Quartulli0c814652013-03-21 09:23:29 +01001937 seq_puts(seq, "\n");
Martin Hundebølld56b1702013-01-25 11:12:39 +01001938
Antonio Quartulli0c814652013-03-21 09:23:29 +01001939 seq_puts(seq, " Outgoing: ");
Martin Hundebølld56b1702013-01-25 11:12:39 +01001940 /* For out_nc_node to this orig_node */
1941 list_for_each_entry_rcu(nc_node,
1942 &orig_node->out_coding_list,
1943 list)
1944 seq_printf(seq, "%pM ",
1945 nc_node->addr);
Antonio Quartulli0c814652013-03-21 09:23:29 +01001946 seq_puts(seq, "\n\n");
Martin Hundebølld56b1702013-01-25 11:12:39 +01001947 }
1948 rcu_read_unlock();
1949 }
1950
1951out:
1952 if (primary_if)
1953 batadv_hardif_free_ref(primary_if);
1954 return 0;
1955}
1956
1957/**
1958 * batadv_nc_init_debugfs - create nc folder and related files in debugfs
1959 * @bat_priv: the bat priv with all the soft interface information
Sven Eckelmann672e7972015-10-31 12:29:30 +01001960 *
1961 * Return: 0 on success or negative error number in case of failure
Martin Hundebølld56b1702013-01-25 11:12:39 +01001962 */
1963int batadv_nc_init_debugfs(struct batadv_priv *bat_priv)
1964{
1965 struct dentry *nc_dir, *file;
1966
1967 nc_dir = debugfs_create_dir("nc", bat_priv->debug_dir);
1968 if (!nc_dir)
1969 goto out;
1970
1971 file = debugfs_create_u8("min_tq", S_IRUGO | S_IWUSR, nc_dir,
1972 &bat_priv->nc.min_tq);
1973 if (!file)
1974 goto out;
1975
Martin Hundebøll95332472013-01-25 11:12:40 +01001976 file = debugfs_create_u32("max_fwd_delay", S_IRUGO | S_IWUSR, nc_dir,
1977 &bat_priv->nc.max_fwd_delay);
1978 if (!file)
1979 goto out;
1980
Martin Hundebøll612d2b42013-01-25 11:12:42 +01001981 file = debugfs_create_u32("max_buffer_time", S_IRUGO | S_IWUSR, nc_dir,
1982 &bat_priv->nc.max_buffer_time);
1983 if (!file)
1984 goto out;
1985
Martin Hundebølld56b1702013-01-25 11:12:39 +01001986 return 0;
1987
1988out:
1989 return -ENOMEM;
1990}