1
2
3
4
5
6
7#include "network-coding.h"
8#include "main.h"
9
10#include <linux/atomic.h>
11#include <linux/bitops.h>
12#include <linux/byteorder/generic.h>
13#include <linux/compiler.h>
14#include <linux/errno.h>
15#include <linux/etherdevice.h>
16#include <linux/gfp.h>
17#include <linux/if_ether.h>
18#include <linux/if_packet.h>
19#include <linux/init.h>
20#include <linux/jhash.h>
21#include <linux/jiffies.h>
22#include <linux/kernel.h>
23#include <linux/kref.h>
24#include <linux/list.h>
25#include <linux/lockdep.h>
26#include <linux/net.h>
27#include <linux/netdevice.h>
28#include <linux/prandom.h>
29#include <linux/printk.h>
30#include <linux/rculist.h>
31#include <linux/rcupdate.h>
32#include <linux/skbuff.h>
33#include <linux/slab.h>
34#include <linux/spinlock.h>
35#include <linux/stddef.h>
36#include <linux/string.h>
37#include <linux/workqueue.h>
38#include <uapi/linux/batadv_packet.h>
39
40#include "hash.h"
41#include "log.h"
42#include "originator.h"
43#include "routing.h"
44#include "send.h"
45#include "tvlv.h"
46
47static struct lock_class_key batadv_nc_coding_hash_lock_class_key;
48static struct lock_class_key batadv_nc_decoding_hash_lock_class_key;
49
50static void batadv_nc_worker(struct work_struct *work);
51static int batadv_nc_recv_coded_packet(struct sk_buff *skb,
52 struct batadv_hard_iface *recv_if);
53
54
55
56
57
58
59int __init batadv_nc_init(void)
60{
61 int ret;
62
63
64 ret = batadv_recv_handler_register(BATADV_CODED,
65 batadv_nc_recv_coded_packet);
66
67 return ret;
68}
69
70
71
72
73
74static void batadv_nc_start_timer(struct batadv_priv *bat_priv)
75{
76 queue_delayed_work(batadv_event_workqueue, &bat_priv->nc.work,
77 msecs_to_jiffies(10));
78}
79
80
81
82
83
84
85static void batadv_nc_tvlv_container_update(struct batadv_priv *bat_priv)
86{
87 char nc_mode;
88
89 nc_mode = atomic_read(&bat_priv->network_coding);
90
91 switch (nc_mode) {
92 case 0:
93 batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_NC, 1);
94 break;
95 case 1:
96 batadv_tvlv_container_register(bat_priv, BATADV_TVLV_NC, 1,
97 NULL, 0);
98 break;
99 }
100}
101
102
103
104
105
106
107void batadv_nc_status_update(struct net_device *net_dev)
108{
109 struct batadv_priv *bat_priv = netdev_priv(net_dev);
110
111 batadv_nc_tvlv_container_update(bat_priv);
112}
113
114
115
116
117
118
119
120
121
122static void batadv_nc_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
123 struct batadv_orig_node *orig,
124 u8 flags,
125 void *tvlv_value, u16 tvlv_value_len)
126{
127 if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND)
128 clear_bit(BATADV_ORIG_CAPA_HAS_NC, &orig->capabilities);
129 else
130 set_bit(BATADV_ORIG_CAPA_HAS_NC, &orig->capabilities);
131}
132
133
134
135
136
137
138
139int batadv_nc_mesh_init(struct batadv_priv *bat_priv)
140{
141 bat_priv->nc.timestamp_fwd_flush = jiffies;
142 bat_priv->nc.timestamp_sniffed_purge = jiffies;
143
144 if (bat_priv->nc.coding_hash || bat_priv->nc.decoding_hash)
145 return 0;
146
147 bat_priv->nc.coding_hash = batadv_hash_new(128);
148 if (!bat_priv->nc.coding_hash)
149 goto err;
150
151 batadv_hash_set_lock_class(bat_priv->nc.coding_hash,
152 &batadv_nc_coding_hash_lock_class_key);
153
154 bat_priv->nc.decoding_hash = batadv_hash_new(128);
155 if (!bat_priv->nc.decoding_hash)
156 goto err;
157
158 batadv_hash_set_lock_class(bat_priv->nc.decoding_hash,
159 &batadv_nc_decoding_hash_lock_class_key);
160
161 INIT_DELAYED_WORK(&bat_priv->nc.work, batadv_nc_worker);
162 batadv_nc_start_timer(bat_priv);
163
164 batadv_tvlv_handler_register(bat_priv, batadv_nc_tvlv_ogm_handler_v1,
165 NULL, BATADV_TVLV_NC, 1,
166 BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
167 batadv_nc_tvlv_container_update(bat_priv);
168 return 0;
169
170err:
171 return -ENOMEM;
172}
173
174
175
176
177
178void batadv_nc_init_bat_priv(struct batadv_priv *bat_priv)
179{
180 atomic_set(&bat_priv->network_coding, 0);
181 bat_priv->nc.min_tq = 200;
182 bat_priv->nc.max_fwd_delay = 10;
183 bat_priv->nc.max_buffer_time = 200;
184}
185
186
187
188
189
190void batadv_nc_init_orig(struct batadv_orig_node *orig_node)
191{
192 INIT_LIST_HEAD(&orig_node->in_coding_list);
193 INIT_LIST_HEAD(&orig_node->out_coding_list);
194 spin_lock_init(&orig_node->in_coding_list_lock);
195 spin_lock_init(&orig_node->out_coding_list_lock);
196}
197
198
199
200
201
202
203static void batadv_nc_node_release(struct kref *ref)
204{
205 struct batadv_nc_node *nc_node;
206
207 nc_node = container_of(ref, struct batadv_nc_node, refcount);
208
209 batadv_orig_node_put(nc_node->orig_node);
210 kfree_rcu(nc_node, rcu);
211}
212
213
214
215
216
217
218static void batadv_nc_node_put(struct batadv_nc_node *nc_node)
219{
220 kref_put(&nc_node->refcount, batadv_nc_node_release);
221}
222
223
224
225
226
227
228static void batadv_nc_path_release(struct kref *ref)
229{
230 struct batadv_nc_path *nc_path;
231
232 nc_path = container_of(ref, struct batadv_nc_path, refcount);
233
234 kfree_rcu(nc_path, rcu);
235}
236
237
238
239
240
241
242static void batadv_nc_path_put(struct batadv_nc_path *nc_path)
243{
244 kref_put(&nc_path->refcount, batadv_nc_path_release);
245}
246
247
248
249
250
251
252static void batadv_nc_packet_free(struct batadv_nc_packet *nc_packet,
253 bool dropped)
254{
255 if (dropped)
256 kfree_skb(nc_packet->skb);
257 else
258 consume_skb(nc_packet->skb);
259
260 batadv_nc_path_put(nc_packet->nc_path);
261 kfree(nc_packet);
262}
263
264
265
266
267
268
269
270
271static bool batadv_nc_to_purge_nc_node(struct batadv_priv *bat_priv,
272 struct batadv_nc_node *nc_node)
273{
274 if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
275 return true;
276
277 return batadv_has_timed_out(nc_node->last_seen, BATADV_NC_NODE_TIMEOUT);
278}
279
280
281
282
283
284
285
286
287static bool batadv_nc_to_purge_nc_path_coding(struct batadv_priv *bat_priv,
288 struct batadv_nc_path *nc_path)
289{
290 if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
291 return true;
292
293
294
295
296 return batadv_has_timed_out(nc_path->last_valid,
297 bat_priv->nc.max_fwd_delay * 10);
298}
299
300
301
302
303
304
305
306
307
308static bool batadv_nc_to_purge_nc_path_decoding(struct batadv_priv *bat_priv,
309 struct batadv_nc_path *nc_path)
310{
311 if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
312 return true;
313
314
315
316
317 return batadv_has_timed_out(nc_path->last_valid,
318 bat_priv->nc.max_buffer_time * 10);
319}
320
321
322
323
324
325
326
327
328
329
330
331
332static void
333batadv_nc_purge_orig_nc_nodes(struct batadv_priv *bat_priv,
334 struct list_head *list,
335 spinlock_t *lock,
336 bool (*to_purge)(struct batadv_priv *,
337 struct batadv_nc_node *))
338{
339 struct batadv_nc_node *nc_node, *nc_node_tmp;
340
341
342 spin_lock_bh(lock);
343 list_for_each_entry_safe(nc_node, nc_node_tmp, list, list) {
344
345
346
347 if (to_purge && !to_purge(bat_priv, nc_node))
348 continue;
349
350 batadv_dbg(BATADV_DBG_NC, bat_priv,
351 "Removing nc_node %pM -> %pM\n",
352 nc_node->addr, nc_node->orig_node->orig);
353 list_del_rcu(&nc_node->list);
354 batadv_nc_node_put(nc_node);
355 }
356 spin_unlock_bh(lock);
357}
358
359
360
361
362
363
364
365
366
367
368
369void batadv_nc_purge_orig(struct batadv_priv *bat_priv,
370 struct batadv_orig_node *orig_node,
371 bool (*to_purge)(struct batadv_priv *,
372 struct batadv_nc_node *))
373{
374
375 batadv_nc_purge_orig_nc_nodes(bat_priv, &orig_node->in_coding_list,
376 &orig_node->in_coding_list_lock,
377 to_purge);
378
379
380 batadv_nc_purge_orig_nc_nodes(bat_priv, &orig_node->out_coding_list,
381 &orig_node->out_coding_list_lock,
382 to_purge);
383}
384
385
386
387
388
389
390static void batadv_nc_purge_orig_hash(struct batadv_priv *bat_priv)
391{
392 struct batadv_hashtable *hash = bat_priv->orig_hash;
393 struct hlist_head *head;
394 struct batadv_orig_node *orig_node;
395 u32 i;
396
397 if (!hash)
398 return;
399
400
401 for (i = 0; i < hash->size; i++) {
402 head = &hash->table[i];
403
404 rcu_read_lock();
405 hlist_for_each_entry_rcu(orig_node, head, hash_entry)
406 batadv_nc_purge_orig(bat_priv, orig_node,
407 batadv_nc_to_purge_nc_node);
408 rcu_read_unlock();
409 }
410}
411
412
413
414
415
416
417
418
419
420
421
422static void batadv_nc_purge_paths(struct batadv_priv *bat_priv,
423 struct batadv_hashtable *hash,
424 bool (*to_purge)(struct batadv_priv *,
425 struct batadv_nc_path *))
426{
427 struct hlist_head *head;
428 struct hlist_node *node_tmp;
429 struct batadv_nc_path *nc_path;
430 spinlock_t *lock;
431 u32 i;
432
433 for (i = 0; i < hash->size; i++) {
434 head = &hash->table[i];
435 lock = &hash->list_locks[i];
436
437
438 spin_lock_bh(lock);
439 hlist_for_each_entry_safe(nc_path, node_tmp, head, hash_entry) {
440
441
442
443 if (to_purge && !to_purge(bat_priv, nc_path))
444 continue;
445
446
447
448
449
450
451 if (!unlikely(list_empty(&nc_path->packet_list))) {
452 net_ratelimited_function(printk,
453 KERN_WARNING
454 "Skipping free of non-empty nc_path (%pM -> %pM)!\n",
455 nc_path->prev_hop,
456 nc_path->next_hop);
457 continue;
458 }
459
460
461 batadv_dbg(BATADV_DBG_NC, bat_priv,
462 "Remove nc_path %pM -> %pM\n",
463 nc_path->prev_hop, nc_path->next_hop);
464 hlist_del_rcu(&nc_path->hash_entry);
465 batadv_nc_path_put(nc_path);
466 }
467 spin_unlock_bh(lock);
468 }
469}
470
471
472
473
474
475
476
477static void batadv_nc_hash_key_gen(struct batadv_nc_path *key, const char *src,
478 const char *dst)
479{
480 memcpy(key->prev_hop, src, sizeof(key->prev_hop));
481 memcpy(key->next_hop, dst, sizeof(key->next_hop));
482}
483
484
485
486
487
488
489
490
491static u32 batadv_nc_hash_choose(const void *data, u32 size)
492{
493 const struct batadv_nc_path *nc_path = data;
494 u32 hash = 0;
495
496 hash = jhash(&nc_path->prev_hop, sizeof(nc_path->prev_hop), hash);
497 hash = jhash(&nc_path->next_hop, sizeof(nc_path->next_hop), hash);
498
499 return hash % size;
500}
501
502
503
504
505
506
507
508
509
510static bool batadv_nc_hash_compare(const struct hlist_node *node,
511 const void *data2)
512{
513 const struct batadv_nc_path *nc_path1, *nc_path2;
514
515 nc_path1 = container_of(node, struct batadv_nc_path, hash_entry);
516 nc_path2 = data2;
517
518
519 if (!batadv_compare_eth(nc_path1->prev_hop, nc_path2->prev_hop))
520 return false;
521
522 if (!batadv_compare_eth(nc_path1->next_hop, nc_path2->next_hop))
523 return false;
524
525 return true;
526}
527
528
529
530
531
532
533
534
535static struct batadv_nc_path *
536batadv_nc_hash_find(struct batadv_hashtable *hash,
537 void *data)
538{
539 struct hlist_head *head;
540 struct batadv_nc_path *nc_path, *nc_path_tmp = NULL;
541 int index;
542
543 if (!hash)
544 return NULL;
545
546 index = batadv_nc_hash_choose(data, hash->size);
547 head = &hash->table[index];
548
549 rcu_read_lock();
550 hlist_for_each_entry_rcu(nc_path, head, hash_entry) {
551 if (!batadv_nc_hash_compare(&nc_path->hash_entry, data))
552 continue;
553
554 if (!kref_get_unless_zero(&nc_path->refcount))
555 continue;
556
557 nc_path_tmp = nc_path;
558 break;
559 }
560 rcu_read_unlock();
561
562 return nc_path_tmp;
563}
564
565
566
567
568
569static void batadv_nc_send_packet(struct batadv_nc_packet *nc_packet)
570{
571 batadv_send_unicast_skb(nc_packet->skb, nc_packet->neigh_node);
572 nc_packet->skb = NULL;
573 batadv_nc_packet_free(nc_packet, false);
574}
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589static bool batadv_nc_sniffed_purge(struct batadv_priv *bat_priv,
590 struct batadv_nc_path *nc_path,
591 struct batadv_nc_packet *nc_packet)
592{
593 unsigned long timeout = bat_priv->nc.max_buffer_time;
594 bool res = false;
595
596 lockdep_assert_held(&nc_path->packet_list_lock);
597
598
599
600
601 if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_ACTIVE &&
602 !batadv_has_timed_out(nc_packet->timestamp, timeout))
603 goto out;
604
605
606 list_del(&nc_packet->list);
607 batadv_nc_packet_free(nc_packet, true);
608
609 res = true;
610
611out:
612 return res;
613}
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628static bool batadv_nc_fwd_flush(struct batadv_priv *bat_priv,
629 struct batadv_nc_path *nc_path,
630 struct batadv_nc_packet *nc_packet)
631{
632 unsigned long timeout = bat_priv->nc.max_fwd_delay;
633
634 lockdep_assert_held(&nc_path->packet_list_lock);
635
636
637
638
639 if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_ACTIVE &&
640 !batadv_has_timed_out(nc_packet->timestamp, timeout))
641 return false;
642
643
644 batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD);
645 batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES,
646 nc_packet->skb->len + ETH_HLEN);
647 list_del(&nc_packet->list);
648 batadv_nc_send_packet(nc_packet);
649
650 return true;
651}
652
653
654
655
656
657
658
659
660
661
662static void
663batadv_nc_process_nc_paths(struct batadv_priv *bat_priv,
664 struct batadv_hashtable *hash,
665 bool (*process_fn)(struct batadv_priv *,
666 struct batadv_nc_path *,
667 struct batadv_nc_packet *))
668{
669 struct hlist_head *head;
670 struct batadv_nc_packet *nc_packet, *nc_packet_tmp;
671 struct batadv_nc_path *nc_path;
672 bool ret;
673 int i;
674
675 if (!hash)
676 return;
677
678
679 for (i = 0; i < hash->size; i++) {
680 head = &hash->table[i];
681
682
683 rcu_read_lock();
684 hlist_for_each_entry_rcu(nc_path, head, hash_entry) {
685
686 spin_lock_bh(&nc_path->packet_list_lock);
687 list_for_each_entry_safe(nc_packet, nc_packet_tmp,
688 &nc_path->packet_list, list) {
689 ret = process_fn(bat_priv, nc_path, nc_packet);
690 if (!ret)
691 break;
692 }
693 spin_unlock_bh(&nc_path->packet_list_lock);
694 }
695 rcu_read_unlock();
696 }
697}
698
699
700
701
702
703
704static void batadv_nc_worker(struct work_struct *work)
705{
706 struct delayed_work *delayed_work;
707 struct batadv_priv_nc *priv_nc;
708 struct batadv_priv *bat_priv;
709 unsigned long timeout;
710
711 delayed_work = to_delayed_work(work);
712 priv_nc = container_of(delayed_work, struct batadv_priv_nc, work);
713 bat_priv = container_of(priv_nc, struct batadv_priv, nc);
714
715 batadv_nc_purge_orig_hash(bat_priv);
716 batadv_nc_purge_paths(bat_priv, bat_priv->nc.coding_hash,
717 batadv_nc_to_purge_nc_path_coding);
718 batadv_nc_purge_paths(bat_priv, bat_priv->nc.decoding_hash,
719 batadv_nc_to_purge_nc_path_decoding);
720
721 timeout = bat_priv->nc.max_fwd_delay;
722
723 if (batadv_has_timed_out(bat_priv->nc.timestamp_fwd_flush, timeout)) {
724 batadv_nc_process_nc_paths(bat_priv, bat_priv->nc.coding_hash,
725 batadv_nc_fwd_flush);
726 bat_priv->nc.timestamp_fwd_flush = jiffies;
727 }
728
729 if (batadv_has_timed_out(bat_priv->nc.timestamp_sniffed_purge,
730 bat_priv->nc.max_buffer_time)) {
731 batadv_nc_process_nc_paths(bat_priv, bat_priv->nc.decoding_hash,
732 batadv_nc_sniffed_purge);
733 bat_priv->nc.timestamp_sniffed_purge = jiffies;
734 }
735
736
737 batadv_nc_start_timer(bat_priv);
738}
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753static bool batadv_can_nc_with_orig(struct batadv_priv *bat_priv,
754 struct batadv_orig_node *orig_node,
755 struct batadv_ogm_packet *ogm_packet)
756{
757 struct batadv_orig_ifinfo *orig_ifinfo;
758 u32 last_real_seqno;
759 u8 last_ttl;
760
761 orig_ifinfo = batadv_orig_ifinfo_get(orig_node, BATADV_IF_DEFAULT);
762 if (!orig_ifinfo)
763 return false;
764
765 last_ttl = orig_ifinfo->last_ttl;
766 last_real_seqno = orig_ifinfo->last_real_seqno;
767 batadv_orig_ifinfo_put(orig_ifinfo);
768
769 if (last_real_seqno != ntohl(ogm_packet->seqno))
770 return false;
771 if (last_ttl != ogm_packet->ttl + 1)
772 return false;
773 if (!batadv_compare_eth(ogm_packet->orig, ogm_packet->prev_sender))
774 return false;
775 if (ogm_packet->tq < bat_priv->nc.min_tq)
776 return false;
777
778 return true;
779}
780
781
782
783
784
785
786
787
788
789
790static struct batadv_nc_node *
791batadv_nc_find_nc_node(struct batadv_orig_node *orig_node,
792 struct batadv_orig_node *orig_neigh_node,
793 bool in_coding)
794{
795 struct batadv_nc_node *nc_node, *nc_node_out = NULL;
796 struct list_head *list;
797
798 if (in_coding)
799 list = &orig_neigh_node->in_coding_list;
800 else
801 list = &orig_neigh_node->out_coding_list;
802
803
804 rcu_read_lock();
805 list_for_each_entry_rcu(nc_node, list, list) {
806 if (!batadv_compare_eth(nc_node->addr, orig_node->orig))
807 continue;
808
809 if (!kref_get_unless_zero(&nc_node->refcount))
810 continue;
811
812
813 nc_node_out = nc_node;
814 break;
815 }
816 rcu_read_unlock();
817
818 return nc_node_out;
819}
820
821
822
823
824
825
826
827
828
829
830
831
832static struct batadv_nc_node *
833batadv_nc_get_nc_node(struct batadv_priv *bat_priv,
834 struct batadv_orig_node *orig_node,
835 struct batadv_orig_node *orig_neigh_node,
836 bool in_coding)
837{
838 struct batadv_nc_node *nc_node;
839 spinlock_t *lock;
840 struct list_head *list;
841
842
843 if (in_coding) {
844 lock = &orig_neigh_node->in_coding_list_lock;
845 list = &orig_neigh_node->in_coding_list;
846 } else {
847 lock = &orig_neigh_node->out_coding_list_lock;
848 list = &orig_neigh_node->out_coding_list;
849 }
850
851 spin_lock_bh(lock);
852
853
854 nc_node = batadv_nc_find_nc_node(orig_node, orig_neigh_node, in_coding);
855
856
857 if (nc_node)
858 goto unlock;
859
860 nc_node = kzalloc(sizeof(*nc_node), GFP_ATOMIC);
861 if (!nc_node)
862 goto unlock;
863
864
865 INIT_LIST_HEAD(&nc_node->list);
866 kref_init(&nc_node->refcount);
867 ether_addr_copy(nc_node->addr, orig_node->orig);
868 kref_get(&orig_neigh_node->refcount);
869 nc_node->orig_node = orig_neigh_node;
870
871 batadv_dbg(BATADV_DBG_NC, bat_priv, "Adding nc_node %pM -> %pM\n",
872 nc_node->addr, nc_node->orig_node->orig);
873
874
875 kref_get(&nc_node->refcount);
876 list_add_tail_rcu(&nc_node->list, list);
877
878unlock:
879 spin_unlock_bh(lock);
880
881 return nc_node;
882}
883
884
885
886
887
888
889
890
891
892
893
894void batadv_nc_update_nc_node(struct batadv_priv *bat_priv,
895 struct batadv_orig_node *orig_node,
896 struct batadv_orig_node *orig_neigh_node,
897 struct batadv_ogm_packet *ogm_packet,
898 int is_single_hop_neigh)
899{
900 struct batadv_nc_node *in_nc_node = NULL;
901 struct batadv_nc_node *out_nc_node = NULL;
902
903
904 if (!atomic_read(&bat_priv->network_coding))
905 goto out;
906
907
908 if (!test_bit(BATADV_ORIG_CAPA_HAS_NC, &orig_node->capabilities))
909 goto out;
910
911
912 if (!batadv_can_nc_with_orig(bat_priv, orig_node, ogm_packet) &&
913 !is_single_hop_neigh)
914 goto out;
915
916
917 in_nc_node = batadv_nc_get_nc_node(bat_priv, orig_node,
918 orig_neigh_node, true);
919 if (!in_nc_node)
920 goto out;
921
922 in_nc_node->last_seen = jiffies;
923
924
925 out_nc_node = batadv_nc_get_nc_node(bat_priv, orig_neigh_node,
926 orig_node, false);
927 if (!out_nc_node)
928 goto out;
929
930 out_nc_node->last_seen = jiffies;
931
932out:
933 if (in_nc_node)
934 batadv_nc_node_put(in_nc_node);
935 if (out_nc_node)
936 batadv_nc_node_put(out_nc_node);
937}
938
939
940
941
942
943
944
945
946
947
948
949static struct batadv_nc_path *batadv_nc_get_path(struct batadv_priv *bat_priv,
950 struct batadv_hashtable *hash,
951 u8 *src,
952 u8 *dst)
953{
954 int hash_added;
955 struct batadv_nc_path *nc_path, nc_path_key;
956
957 batadv_nc_hash_key_gen(&nc_path_key, src, dst);
958
959
960 nc_path = batadv_nc_hash_find(hash, (void *)&nc_path_key);
961
962 if (nc_path) {
963
964 nc_path->last_valid = jiffies;
965 return nc_path;
966 }
967
968
969 nc_path = kzalloc(sizeof(*nc_path), GFP_ATOMIC);
970
971 if (!nc_path)
972 return NULL;
973
974
975 INIT_LIST_HEAD(&nc_path->packet_list);
976 spin_lock_init(&nc_path->packet_list_lock);
977 kref_init(&nc_path->refcount);
978 nc_path->last_valid = jiffies;
979 ether_addr_copy(nc_path->next_hop, dst);
980 ether_addr_copy(nc_path->prev_hop, src);
981
982 batadv_dbg(BATADV_DBG_NC, bat_priv, "Adding nc_path %pM -> %pM\n",
983 nc_path->prev_hop,
984 nc_path->next_hop);
985
986
987 kref_get(&nc_path->refcount);
988 hash_added = batadv_hash_add(hash, batadv_nc_hash_compare,
989 batadv_nc_hash_choose, &nc_path_key,
990 &nc_path->hash_entry);
991
992 if (hash_added < 0) {
993 kfree(nc_path);
994 return NULL;
995 }
996
997 return nc_path;
998}
999
1000
1001
1002
1003
1004
1005
1006
1007static u8 batadv_nc_random_weight_tq(u8 tq)
1008{
1009
1010 u8 rand_tq = prandom_u32_max(BATADV_TQ_MAX_VALUE + 1 - tq);
1011
1012
1013 return BATADV_TQ_MAX_VALUE - rand_tq;
1014}
1015
1016
1017
1018
1019
1020
1021
1022static void batadv_nc_memxor(char *dst, const char *src, unsigned int len)
1023{
1024 unsigned int i;
1025
1026 for (i = 0; i < len; ++i)
1027 dst[i] ^= src[i];
1028}
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041static bool batadv_nc_code_packets(struct batadv_priv *bat_priv,
1042 struct sk_buff *skb,
1043 struct ethhdr *ethhdr,
1044 struct batadv_nc_packet *nc_packet,
1045 struct batadv_neigh_node *neigh_node)
1046{
1047 u8 tq_weighted_neigh, tq_weighted_coding, tq_tmp;
1048 struct sk_buff *skb_dest, *skb_src;
1049 struct batadv_unicast_packet *packet1;
1050 struct batadv_unicast_packet *packet2;
1051 struct batadv_coded_packet *coded_packet;
1052 struct batadv_neigh_node *neigh_tmp, *router_neigh, *first_dest;
1053 struct batadv_neigh_node *router_coding = NULL, *second_dest;
1054 struct batadv_neigh_ifinfo *router_neigh_ifinfo = NULL;
1055 struct batadv_neigh_ifinfo *router_coding_ifinfo = NULL;
1056 u8 *first_source, *second_source;
1057 __be32 packet_id1, packet_id2;
1058 size_t count;
1059 bool res = false;
1060 int coding_len;
1061 int unicast_size = sizeof(*packet1);
1062 int coded_size = sizeof(*coded_packet);
1063 int header_add = coded_size - unicast_size;
1064
1065
1066
1067
1068 router_neigh = batadv_orig_router_get(neigh_node->orig_node,
1069 BATADV_IF_DEFAULT);
1070 if (!router_neigh)
1071 goto out;
1072
1073 router_neigh_ifinfo = batadv_neigh_ifinfo_get(router_neigh,
1074 BATADV_IF_DEFAULT);
1075 if (!router_neigh_ifinfo)
1076 goto out;
1077
1078 neigh_tmp = nc_packet->neigh_node;
1079 router_coding = batadv_orig_router_get(neigh_tmp->orig_node,
1080 BATADV_IF_DEFAULT);
1081 if (!router_coding)
1082 goto out;
1083
1084 router_coding_ifinfo = batadv_neigh_ifinfo_get(router_coding,
1085 BATADV_IF_DEFAULT);
1086 if (!router_coding_ifinfo)
1087 goto out;
1088
1089 tq_tmp = router_neigh_ifinfo->bat_iv.tq_avg;
1090 tq_weighted_neigh = batadv_nc_random_weight_tq(tq_tmp);
1091 tq_tmp = router_coding_ifinfo->bat_iv.tq_avg;
1092 tq_weighted_coding = batadv_nc_random_weight_tq(tq_tmp);
1093
1094
1095
1096
1097 if (tq_weighted_neigh >= tq_weighted_coding) {
1098
1099 first_dest = nc_packet->neigh_node;
1100 first_source = nc_packet->nc_path->prev_hop;
1101 second_dest = neigh_node;
1102 second_source = ethhdr->h_source;
1103 packet1 = (struct batadv_unicast_packet *)nc_packet->skb->data;
1104 packet2 = (struct batadv_unicast_packet *)skb->data;
1105 packet_id1 = nc_packet->packet_id;
1106 packet_id2 = batadv_skb_crc32(skb,
1107 skb->data + sizeof(*packet2));
1108 } else {
1109
1110 first_dest = neigh_node;
1111 first_source = ethhdr->h_source;
1112 second_dest = nc_packet->neigh_node;
1113 second_source = nc_packet->nc_path->prev_hop;
1114 packet1 = (struct batadv_unicast_packet *)skb->data;
1115 packet2 = (struct batadv_unicast_packet *)nc_packet->skb->data;
1116 packet_id1 = batadv_skb_crc32(skb,
1117 skb->data + sizeof(*packet1));
1118 packet_id2 = nc_packet->packet_id;
1119 }
1120
1121
1122
1123
1124 if (skb->len <= nc_packet->skb->len) {
1125 skb_dest = nc_packet->skb;
1126 skb_src = skb;
1127 } else {
1128 skb_dest = skb;
1129 skb_src = nc_packet->skb;
1130 }
1131
1132
1133 coding_len = skb_src->len - unicast_size;
1134
1135 if (skb_linearize(skb_dest) < 0 || skb_linearize(skb_src) < 0)
1136 goto out;
1137
1138 skb_push(skb_dest, header_add);
1139
1140 coded_packet = (struct batadv_coded_packet *)skb_dest->data;
1141 skb_reset_mac_header(skb_dest);
1142
1143 coded_packet->packet_type = BATADV_CODED;
1144 coded_packet->version = BATADV_COMPAT_VERSION;
1145 coded_packet->ttl = packet1->ttl;
1146
1147
1148 ether_addr_copy(coded_packet->first_source, first_source);
1149 ether_addr_copy(coded_packet->first_orig_dest, packet1->dest);
1150 coded_packet->first_crc = packet_id1;
1151 coded_packet->first_ttvn = packet1->ttvn;
1152
1153
1154 ether_addr_copy(coded_packet->second_dest, second_dest->addr);
1155 ether_addr_copy(coded_packet->second_source, second_source);
1156 ether_addr_copy(coded_packet->second_orig_dest, packet2->dest);
1157 coded_packet->second_crc = packet_id2;
1158 coded_packet->second_ttl = packet2->ttl;
1159 coded_packet->second_ttvn = packet2->ttvn;
1160 coded_packet->coded_len = htons(coding_len);
1161
1162
1163 batadv_nc_memxor(skb_dest->data + coded_size,
1164 skb_src->data + unicast_size, coding_len);
1165
1166
1167 if (BATADV_SKB_CB(skb_src)->decoded &&
1168 BATADV_SKB_CB(skb_dest)->decoded) {
1169
1170 count = skb_src->len + ETH_HLEN;
1171 count += skb_dest->len + ETH_HLEN;
1172 batadv_add_counter(bat_priv, BATADV_CNT_NC_RECODE, 2);
1173 batadv_add_counter(bat_priv, BATADV_CNT_NC_RECODE_BYTES, count);
1174 } else if (!BATADV_SKB_CB(skb_src)->decoded &&
1175 !BATADV_SKB_CB(skb_dest)->decoded) {
1176
1177 count = skb_src->len + ETH_HLEN;
1178 count += skb_dest->len + ETH_HLEN;
1179 batadv_add_counter(bat_priv, BATADV_CNT_NC_CODE, 2);
1180 batadv_add_counter(bat_priv, BATADV_CNT_NC_CODE_BYTES, count);
1181 } else if (BATADV_SKB_CB(skb_src)->decoded &&
1182 !BATADV_SKB_CB(skb_dest)->decoded) {
1183
1184 batadv_inc_counter(bat_priv, BATADV_CNT_NC_RECODE);
1185 batadv_add_counter(bat_priv, BATADV_CNT_NC_RECODE_BYTES,
1186 skb_src->len + ETH_HLEN);
1187 batadv_inc_counter(bat_priv, BATADV_CNT_NC_CODE);
1188 batadv_add_counter(bat_priv, BATADV_CNT_NC_CODE_BYTES,
1189 skb_dest->len + ETH_HLEN);
1190 } else if (!BATADV_SKB_CB(skb_src)->decoded &&
1191 BATADV_SKB_CB(skb_dest)->decoded) {
1192
1193 batadv_inc_counter(bat_priv, BATADV_CNT_NC_CODE);
1194 batadv_add_counter(bat_priv, BATADV_CNT_NC_CODE_BYTES,
1195 skb_src->len + ETH_HLEN);
1196 batadv_inc_counter(bat_priv, BATADV_CNT_NC_RECODE);
1197 batadv_add_counter(bat_priv, BATADV_CNT_NC_RECODE_BYTES,
1198 skb_dest->len + ETH_HLEN);
1199 }
1200
1201
1202 consume_skb(skb_src);
1203
1204
1205 nc_packet->skb = NULL;
1206 batadv_nc_packet_free(nc_packet, false);
1207
1208
1209 batadv_send_unicast_skb(skb_dest, first_dest);
1210 res = true;
1211out:
1212 if (router_neigh)
1213 batadv_neigh_node_put(router_neigh);
1214 if (router_coding)
1215 batadv_neigh_node_put(router_coding);
1216 if (router_neigh_ifinfo)
1217 batadv_neigh_ifinfo_put(router_neigh_ifinfo);
1218 if (router_coding_ifinfo)
1219 batadv_neigh_ifinfo_put(router_coding_ifinfo);
1220 return res;
1221}
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240static bool batadv_nc_skb_coding_possible(struct sk_buff *skb, u8 *dst, u8 *src)
1241{
1242 if (BATADV_SKB_CB(skb)->decoded && !batadv_compare_eth(dst, src))
1243 return false;
1244 return true;
1245}
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258static struct batadv_nc_packet *
1259batadv_nc_path_search(struct batadv_priv *bat_priv,
1260 struct batadv_nc_node *in_nc_node,
1261 struct batadv_nc_node *out_nc_node,
1262 struct sk_buff *skb,
1263 u8 *eth_dst)
1264{
1265 struct batadv_nc_path *nc_path, nc_path_key;
1266 struct batadv_nc_packet *nc_packet_out = NULL;
1267 struct batadv_nc_packet *nc_packet, *nc_packet_tmp;
1268 struct batadv_hashtable *hash = bat_priv->nc.coding_hash;
1269 int idx;
1270
1271 if (!hash)
1272 return NULL;
1273
1274
1275 batadv_nc_hash_key_gen(&nc_path_key, in_nc_node->addr,
1276 out_nc_node->addr);
1277 idx = batadv_nc_hash_choose(&nc_path_key, hash->size);
1278
1279
1280 rcu_read_lock();
1281 hlist_for_each_entry_rcu(nc_path, &hash->table[idx], hash_entry) {
1282 if (!batadv_compare_eth(nc_path->prev_hop, in_nc_node->addr))
1283 continue;
1284
1285 if (!batadv_compare_eth(nc_path->next_hop, out_nc_node->addr))
1286 continue;
1287
1288 spin_lock_bh(&nc_path->packet_list_lock);
1289 if (list_empty(&nc_path->packet_list)) {
1290 spin_unlock_bh(&nc_path->packet_list_lock);
1291 continue;
1292 }
1293
1294 list_for_each_entry_safe(nc_packet, nc_packet_tmp,
1295 &nc_path->packet_list, list) {
1296 if (!batadv_nc_skb_coding_possible(nc_packet->skb,
1297 eth_dst,
1298 in_nc_node->addr))
1299 continue;
1300
1301
1302 list_del(&nc_packet->list);
1303 nc_packet_out = nc_packet;
1304 break;
1305 }
1306
1307 spin_unlock_bh(&nc_path->packet_list_lock);
1308 break;
1309 }
1310 rcu_read_unlock();
1311
1312 return nc_packet_out;
1313}
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326static struct batadv_nc_packet *
1327batadv_nc_skb_src_search(struct batadv_priv *bat_priv,
1328 struct sk_buff *skb,
1329 u8 *eth_dst,
1330 u8 *eth_src,
1331 struct batadv_nc_node *in_nc_node)
1332{
1333 struct batadv_orig_node *orig_node;
1334 struct batadv_nc_node *out_nc_node;
1335 struct batadv_nc_packet *nc_packet = NULL;
1336
1337 orig_node = batadv_orig_hash_find(bat_priv, eth_src);
1338 if (!orig_node)
1339 return NULL;
1340
1341 rcu_read_lock();
1342 list_for_each_entry_rcu(out_nc_node,
1343 &orig_node->out_coding_list, list) {
1344
1345 if (!batadv_nc_skb_coding_possible(skb,
1346 out_nc_node->addr, eth_src))
1347 continue;
1348
1349
1350 nc_packet = batadv_nc_path_search(bat_priv, in_nc_node,
1351 out_nc_node, skb, eth_dst);
1352 if (nc_packet)
1353 break;
1354 }
1355 rcu_read_unlock();
1356
1357 batadv_orig_node_put(orig_node);
1358 return nc_packet;
1359}
1360
1361
1362
1363
1364
1365
1366
1367
1368static void batadv_nc_skb_store_before_coding(struct batadv_priv *bat_priv,
1369 struct sk_buff *skb,
1370 u8 *eth_dst_new)
1371{
1372 struct ethhdr *ethhdr;
1373
1374
1375 skb = pskb_copy_for_clone(skb, GFP_ATOMIC);
1376 if (!skb)
1377 return;
1378
1379
1380 ethhdr = eth_hdr(skb);
1381 ether_addr_copy(ethhdr->h_source, ethhdr->h_dest);
1382 ether_addr_copy(ethhdr->h_dest, eth_dst_new);
1383
1384
1385 skb_push(skb, ETH_HLEN);
1386
1387
1388 batadv_nc_skb_store_for_decoding(bat_priv, skb);
1389
1390
1391
1392
1393 consume_skb(skb);
1394}
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409static bool batadv_nc_skb_dst_search(struct sk_buff *skb,
1410 struct batadv_neigh_node *neigh_node,
1411 struct ethhdr *ethhdr)
1412{
1413 struct net_device *netdev = neigh_node->if_incoming->soft_iface;
1414 struct batadv_priv *bat_priv = netdev_priv(netdev);
1415 struct batadv_orig_node *orig_node = neigh_node->orig_node;
1416 struct batadv_nc_node *nc_node;
1417 struct batadv_nc_packet *nc_packet = NULL;
1418
1419 rcu_read_lock();
1420 list_for_each_entry_rcu(nc_node, &orig_node->in_coding_list, list) {
1421
1422 nc_packet = batadv_nc_skb_src_search(bat_priv, skb,
1423 neigh_node->addr,
1424 ethhdr->h_source, nc_node);
1425
1426
1427 if (nc_packet)
1428 break;
1429 }
1430 rcu_read_unlock();
1431
1432 if (!nc_packet)
1433 return false;
1434
1435
1436 batadv_nc_skb_store_before_coding(bat_priv, skb,
1437 neigh_node->addr);
1438 batadv_nc_skb_store_before_coding(bat_priv, nc_packet->skb,
1439 nc_packet->neigh_node->addr);
1440
1441
1442 if (batadv_nc_code_packets(bat_priv, skb, ethhdr, nc_packet,
1443 neigh_node))
1444 return true;
1445
1446
1447
1448
1449
1450 batadv_nc_send_packet(nc_packet);
1451 return false;
1452}
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463static bool batadv_nc_skb_add_to_path(struct sk_buff *skb,
1464 struct batadv_nc_path *nc_path,
1465 struct batadv_neigh_node *neigh_node,
1466 __be32 packet_id)
1467{
1468 struct batadv_nc_packet *nc_packet;
1469
1470 nc_packet = kzalloc(sizeof(*nc_packet), GFP_ATOMIC);
1471 if (!nc_packet)
1472 return false;
1473
1474
1475 nc_packet->timestamp = jiffies;
1476 nc_packet->packet_id = packet_id;
1477 nc_packet->skb = skb;
1478 nc_packet->neigh_node = neigh_node;
1479 nc_packet->nc_path = nc_path;
1480
1481
1482 spin_lock_bh(&nc_path->packet_list_lock);
1483 list_add_tail(&nc_packet->list, &nc_path->packet_list);
1484 spin_unlock_bh(&nc_path->packet_list_lock);
1485
1486 return true;
1487}
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497bool batadv_nc_skb_forward(struct sk_buff *skb,
1498 struct batadv_neigh_node *neigh_node)
1499{
1500 const struct net_device *netdev = neigh_node->if_incoming->soft_iface;
1501 struct batadv_priv *bat_priv = netdev_priv(netdev);
1502 struct batadv_unicast_packet *packet;
1503 struct batadv_nc_path *nc_path;
1504 struct ethhdr *ethhdr = eth_hdr(skb);
1505 __be32 packet_id;
1506 u8 *payload;
1507
1508
1509 if (!atomic_read(&bat_priv->network_coding))
1510 goto out;
1511
1512
1513 payload = skb_network_header(skb);
1514 packet = (struct batadv_unicast_packet *)payload;
1515 if (packet->packet_type != BATADV_UNICAST)
1516 goto out;
1517
1518
1519 if (batadv_nc_skb_dst_search(skb, neigh_node, ethhdr))
1520 return true;
1521
1522
1523 nc_path = batadv_nc_get_path(bat_priv,
1524 bat_priv->nc.coding_hash,
1525 ethhdr->h_source,
1526 neigh_node->addr);
1527
1528 if (!nc_path)
1529 goto out;
1530
1531
1532 packet_id = batadv_skb_crc32(skb, payload + sizeof(*packet));
1533 if (!batadv_nc_skb_add_to_path(skb, nc_path, neigh_node, packet_id))
1534 goto free_nc_path;
1535
1536
1537 return true;
1538
1539free_nc_path:
1540 batadv_nc_path_put(nc_path);
1541out:
1542
1543 return false;
1544}
1545
1546
1547
1548
1549
1550
1551
1552void batadv_nc_skb_store_for_decoding(struct batadv_priv *bat_priv,
1553 struct sk_buff *skb)
1554{
1555 struct batadv_unicast_packet *packet;
1556 struct batadv_nc_path *nc_path;
1557 struct ethhdr *ethhdr = eth_hdr(skb);
1558 __be32 packet_id;
1559 u8 *payload;
1560
1561
1562 if (!atomic_read(&bat_priv->network_coding))
1563 goto out;
1564
1565
1566 payload = skb_network_header(skb);
1567 packet = (struct batadv_unicast_packet *)payload;
1568 if (packet->packet_type != BATADV_UNICAST)
1569 goto out;
1570
1571
1572 nc_path = batadv_nc_get_path(bat_priv,
1573 bat_priv->nc.decoding_hash,
1574 ethhdr->h_source,
1575 ethhdr->h_dest);
1576
1577 if (!nc_path)
1578 goto out;
1579
1580
1581 skb = skb_clone(skb, GFP_ATOMIC);
1582 if (unlikely(!skb))
1583 goto free_nc_path;
1584
1585 if (unlikely(!pskb_may_pull(skb, ETH_HLEN)))
1586 goto free_skb;
1587
1588 if (unlikely(!skb_pull_rcsum(skb, ETH_HLEN)))
1589 goto free_skb;
1590
1591
1592 packet_id = batadv_skb_crc32(skb, payload + sizeof(*packet));
1593 if (!batadv_nc_skb_add_to_path(skb, nc_path, NULL, packet_id))
1594 goto free_skb;
1595
1596 batadv_inc_counter(bat_priv, BATADV_CNT_NC_BUFFER);
1597 return;
1598
1599free_skb:
1600 kfree_skb(skb);
1601free_nc_path:
1602 batadv_nc_path_put(nc_path);
1603out:
1604 return;
1605}
1606
1607
1608
1609
1610
1611
1612
1613void batadv_nc_skb_store_sniffed_unicast(struct batadv_priv *bat_priv,
1614 struct sk_buff *skb)
1615{
1616 struct ethhdr *ethhdr = eth_hdr(skb);
1617
1618 if (batadv_is_my_mac(bat_priv, ethhdr->h_dest))
1619 return;
1620
1621
1622 skb_push(skb, ETH_HLEN);
1623
1624 batadv_nc_skb_store_for_decoding(bat_priv, skb);
1625}
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637static struct batadv_unicast_packet *
1638batadv_nc_skb_decode_packet(struct batadv_priv *bat_priv, struct sk_buff *skb,
1639 struct batadv_nc_packet *nc_packet)
1640{
1641 const int h_size = sizeof(struct batadv_unicast_packet);
1642 const int h_diff = sizeof(struct batadv_coded_packet) - h_size;
1643 struct batadv_unicast_packet *unicast_packet;
1644 struct batadv_coded_packet coded_packet_tmp;
1645 struct ethhdr *ethhdr, ethhdr_tmp;
1646 u8 *orig_dest, ttl, ttvn;
1647 unsigned int coding_len;
1648 int err;
1649
1650
1651 memcpy(&coded_packet_tmp, skb->data, sizeof(coded_packet_tmp));
1652 memcpy(ðhdr_tmp, skb_mac_header(skb), sizeof(ethhdr_tmp));
1653
1654 if (skb_cow(skb, 0) < 0)
1655 return NULL;
1656
1657 if (unlikely(!skb_pull_rcsum(skb, h_diff)))
1658 return NULL;
1659
1660
1661
1662
1663 skb_set_mac_header(skb, -ETH_HLEN);
1664 skb_reset_network_header(skb);
1665
1666
1667 ethhdr = eth_hdr(skb);
1668 *ethhdr = ethhdr_tmp;
1669
1670
1671
1672
1673 if (batadv_is_my_mac(bat_priv, coded_packet_tmp.second_dest)) {
1674
1675
1676
1677
1678 ether_addr_copy(ethhdr->h_dest, coded_packet_tmp.second_dest);
1679 skb->pkt_type = PACKET_HOST;
1680
1681 orig_dest = coded_packet_tmp.second_orig_dest;
1682 ttl = coded_packet_tmp.second_ttl;
1683 ttvn = coded_packet_tmp.second_ttvn;
1684 } else {
1685 orig_dest = coded_packet_tmp.first_orig_dest;
1686 ttl = coded_packet_tmp.ttl;
1687 ttvn = coded_packet_tmp.first_ttvn;
1688 }
1689
1690 coding_len = ntohs(coded_packet_tmp.coded_len);
1691
1692 if (coding_len > skb->len)
1693 return NULL;
1694
1695
1696
1697
1698 batadv_nc_memxor(skb->data + h_size,
1699 nc_packet->skb->data + h_size,
1700 coding_len);
1701
1702
1703 if (nc_packet->skb->len > coding_len + h_size) {
1704 err = pskb_trim_rcsum(skb, coding_len + h_size);
1705 if (err)
1706 return NULL;
1707 }
1708
1709
1710 unicast_packet = (struct batadv_unicast_packet *)skb->data;
1711 unicast_packet->packet_type = BATADV_UNICAST;
1712 unicast_packet->version = BATADV_COMPAT_VERSION;
1713 unicast_packet->ttl = ttl;
1714 ether_addr_copy(unicast_packet->dest, orig_dest);
1715 unicast_packet->ttvn = ttvn;
1716
1717 batadv_nc_packet_free(nc_packet, false);
1718 return unicast_packet;
1719}
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730static struct batadv_nc_packet *
1731batadv_nc_find_decoding_packet(struct batadv_priv *bat_priv,
1732 struct ethhdr *ethhdr,
1733 struct batadv_coded_packet *coded)
1734{
1735 struct batadv_hashtable *hash = bat_priv->nc.decoding_hash;
1736 struct batadv_nc_packet *tmp_nc_packet, *nc_packet = NULL;
1737 struct batadv_nc_path *nc_path, nc_path_key;
1738 u8 *dest, *source;
1739 __be32 packet_id;
1740 int index;
1741
1742 if (!hash)
1743 return NULL;
1744
1745
1746 dest = ethhdr->h_source;
1747 if (!batadv_is_my_mac(bat_priv, coded->second_dest)) {
1748 source = coded->second_source;
1749 packet_id = coded->second_crc;
1750 } else {
1751 source = coded->first_source;
1752 packet_id = coded->first_crc;
1753 }
1754
1755 batadv_nc_hash_key_gen(&nc_path_key, source, dest);
1756 index = batadv_nc_hash_choose(&nc_path_key, hash->size);
1757
1758
1759 rcu_read_lock();
1760 hlist_for_each_entry_rcu(nc_path, &hash->table[index], hash_entry) {
1761
1762 spin_lock_bh(&nc_path->packet_list_lock);
1763 list_for_each_entry(tmp_nc_packet,
1764 &nc_path->packet_list, list) {
1765 if (packet_id == tmp_nc_packet->packet_id) {
1766 list_del(&tmp_nc_packet->list);
1767
1768 nc_packet = tmp_nc_packet;
1769 break;
1770 }
1771 }
1772 spin_unlock_bh(&nc_path->packet_list_lock);
1773
1774 if (nc_packet)
1775 break;
1776 }
1777 rcu_read_unlock();
1778
1779 if (!nc_packet)
1780 batadv_dbg(BATADV_DBG_NC, bat_priv,
1781 "No decoding packet found for %u\n", packet_id);
1782
1783 return nc_packet;
1784}
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795static int batadv_nc_recv_coded_packet(struct sk_buff *skb,
1796 struct batadv_hard_iface *recv_if)
1797{
1798 struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1799 struct batadv_unicast_packet *unicast_packet;
1800 struct batadv_coded_packet *coded_packet;
1801 struct batadv_nc_packet *nc_packet;
1802 struct ethhdr *ethhdr;
1803 int hdr_size = sizeof(*coded_packet);
1804
1805
1806 if (!atomic_read(&bat_priv->network_coding))
1807 goto free_skb;
1808
1809
1810 if (unlikely(!pskb_may_pull(skb, hdr_size)))
1811 goto free_skb;
1812
1813 coded_packet = (struct batadv_coded_packet *)skb->data;
1814 ethhdr = eth_hdr(skb);
1815
1816
1817 if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest) &&
1818 !batadv_is_my_mac(bat_priv, coded_packet->second_dest))
1819 goto free_skb;
1820
1821
1822 if (batadv_is_my_mac(bat_priv, coded_packet->second_dest))
1823 batadv_inc_counter(bat_priv, BATADV_CNT_NC_SNIFFED);
1824
1825 nc_packet = batadv_nc_find_decoding_packet(bat_priv, ethhdr,
1826 coded_packet);
1827 if (!nc_packet) {
1828 batadv_inc_counter(bat_priv, BATADV_CNT_NC_DECODE_FAILED);
1829 goto free_skb;
1830 }
1831
1832
1833 if (skb_linearize(skb) < 0)
1834 goto free_nc_packet;
1835
1836 if (skb_linearize(nc_packet->skb) < 0)
1837 goto free_nc_packet;
1838
1839
1840 unicast_packet = batadv_nc_skb_decode_packet(bat_priv, skb, nc_packet);
1841 if (!unicast_packet) {
1842 batadv_inc_counter(bat_priv, BATADV_CNT_NC_DECODE_FAILED);
1843 goto free_nc_packet;
1844 }
1845
1846
1847 BATADV_SKB_CB(skb)->decoded = true;
1848 batadv_inc_counter(bat_priv, BATADV_CNT_NC_DECODE);
1849 batadv_add_counter(bat_priv, BATADV_CNT_NC_DECODE_BYTES,
1850 skb->len + ETH_HLEN);
1851 return batadv_recv_unicast_packet(skb, recv_if);
1852
1853free_nc_packet:
1854 batadv_nc_packet_free(nc_packet, true);
1855free_skb:
1856 kfree_skb(skb);
1857
1858 return NET_RX_DROP;
1859}
1860
1861
1862
1863
1864
1865void batadv_nc_mesh_free(struct batadv_priv *bat_priv)
1866{
1867 batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_NC, 1);
1868 batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_NC, 1);
1869 cancel_delayed_work_sync(&bat_priv->nc.work);
1870
1871 batadv_nc_purge_paths(bat_priv, bat_priv->nc.coding_hash, NULL);
1872 batadv_hash_destroy(bat_priv->nc.coding_hash);
1873 batadv_nc_purge_paths(bat_priv, bat_priv->nc.decoding_hash, NULL);
1874 batadv_hash_destroy(bat_priv->nc.decoding_hash);
1875}
1876