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Merge branch 'next/spring-cleaning' into next/cleanup
[karo-tx-linux.git] / net / batman-adv / bat_iv_ogm.c
1 /* Copyright (C) 2007-2013 B.A.T.M.A.N. contributors:
2  *
3  * Marek Lindner, Simon Wunderlich
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of version 2 of the GNU General Public
7  * License as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17  * 02110-1301, USA
18  */
19
20 #include "main.h"
21 #include "translation-table.h"
22 #include "ring_buffer.h"
23 #include "originator.h"
24 #include "routing.h"
25 #include "gateway_common.h"
26 #include "gateway_client.h"
27 #include "hard-interface.h"
28 #include "send.h"
29 #include "bat_algo.h"
30
31 static struct batadv_neigh_node *
32 batadv_iv_ogm_neigh_new(struct batadv_hard_iface *hard_iface,
33                         const uint8_t *neigh_addr,
34                         struct batadv_orig_node *orig_node,
35                         struct batadv_orig_node *orig_neigh, __be32 seqno)
36 {
37         struct batadv_neigh_node *neigh_node;
38
39         neigh_node = batadv_neigh_node_new(hard_iface, neigh_addr,
40                                            ntohl(seqno));
41         if (!neigh_node)
42                 goto out;
43
44         INIT_LIST_HEAD(&neigh_node->bonding_list);
45
46         neigh_node->orig_node = orig_neigh;
47         neigh_node->if_incoming = hard_iface;
48
49         spin_lock_bh(&orig_node->neigh_list_lock);
50         hlist_add_head_rcu(&neigh_node->list, &orig_node->neigh_list);
51         spin_unlock_bh(&orig_node->neigh_list_lock);
52
53 out:
54         return neigh_node;
55 }
56
57 static int batadv_iv_ogm_iface_enable(struct batadv_hard_iface *hard_iface)
58 {
59         struct batadv_ogm_packet *batadv_ogm_packet;
60         unsigned char *ogm_buff;
61         uint32_t random_seqno;
62         int res = -ENOMEM;
63
64         /* randomize initial seqno to avoid collision */
65         get_random_bytes(&random_seqno, sizeof(random_seqno));
66         atomic_set(&hard_iface->bat_iv.ogm_seqno, random_seqno);
67
68         hard_iface->bat_iv.ogm_buff_len = BATADV_OGM_HLEN;
69         ogm_buff = kmalloc(hard_iface->bat_iv.ogm_buff_len, GFP_ATOMIC);
70         if (!ogm_buff)
71                 goto out;
72
73         hard_iface->bat_iv.ogm_buff = ogm_buff;
74
75         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
76         batadv_ogm_packet->header.packet_type = BATADV_IV_OGM;
77         batadv_ogm_packet->header.version = BATADV_COMPAT_VERSION;
78         batadv_ogm_packet->header.ttl = 2;
79         batadv_ogm_packet->flags = BATADV_NO_FLAGS;
80         batadv_ogm_packet->tq = BATADV_TQ_MAX_VALUE;
81         batadv_ogm_packet->tt_num_changes = 0;
82         batadv_ogm_packet->ttvn = 0;
83
84         res = 0;
85
86 out:
87         return res;
88 }
89
90 static void batadv_iv_ogm_iface_disable(struct batadv_hard_iface *hard_iface)
91 {
92         kfree(hard_iface->bat_iv.ogm_buff);
93         hard_iface->bat_iv.ogm_buff = NULL;
94 }
95
96 static void batadv_iv_ogm_iface_update_mac(struct batadv_hard_iface *hard_iface)
97 {
98         struct batadv_ogm_packet *batadv_ogm_packet;
99         unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;
100
101         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
102         memcpy(batadv_ogm_packet->orig,
103                hard_iface->net_dev->dev_addr, ETH_ALEN);
104         memcpy(batadv_ogm_packet->prev_sender,
105                hard_iface->net_dev->dev_addr, ETH_ALEN);
106 }
107
108 static void
109 batadv_iv_ogm_primary_iface_set(struct batadv_hard_iface *hard_iface)
110 {
111         struct batadv_ogm_packet *batadv_ogm_packet;
112         unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;
113
114         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
115         batadv_ogm_packet->flags = BATADV_PRIMARIES_FIRST_HOP;
116         batadv_ogm_packet->header.ttl = BATADV_TTL;
117 }
118
119 /* when do we schedule our own ogm to be sent */
120 static unsigned long
121 batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv)
122 {
123         unsigned int msecs;
124
125         msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
126         msecs += prandom_u32() % (2 * BATADV_JITTER);
127
128         return jiffies + msecs_to_jiffies(msecs);
129 }
130
131 /* when do we schedule a ogm packet to be sent */
132 static unsigned long batadv_iv_ogm_fwd_send_time(void)
133 {
134         return jiffies + msecs_to_jiffies(prandom_u32() % (BATADV_JITTER / 2));
135 }
136
137 /* apply hop penalty for a normal link */
138 static uint8_t batadv_hop_penalty(uint8_t tq,
139                                   const struct batadv_priv *bat_priv)
140 {
141         int hop_penalty = atomic_read(&bat_priv->hop_penalty);
142         int new_tq;
143
144         new_tq = tq * (BATADV_TQ_MAX_VALUE - hop_penalty);
145         new_tq /= BATADV_TQ_MAX_VALUE;
146
147         return new_tq;
148 }
149
150 /* is there another aggregated packet here? */
151 static int batadv_iv_ogm_aggr_packet(int buff_pos, int packet_len,
152                                      int tt_num_changes)
153 {
154         int next_buff_pos = 0;
155
156         next_buff_pos += buff_pos + BATADV_OGM_HLEN;
157         next_buff_pos += batadv_tt_len(tt_num_changes);
158
159         return (next_buff_pos <= packet_len) &&
160                (next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES);
161 }
162
163 /* send a batman ogm to a given interface */
164 static void batadv_iv_ogm_send_to_if(struct batadv_forw_packet *forw_packet,
165                                      struct batadv_hard_iface *hard_iface)
166 {
167         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
168         char *fwd_str;
169         uint8_t packet_num;
170         int16_t buff_pos;
171         struct batadv_ogm_packet *batadv_ogm_packet;
172         struct sk_buff *skb;
173         uint8_t *packet_pos;
174
175         if (hard_iface->if_status != BATADV_IF_ACTIVE)
176                 return;
177
178         packet_num = 0;
179         buff_pos = 0;
180         packet_pos = forw_packet->skb->data;
181         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
182
183         /* adjust all flags and log packets */
184         while (batadv_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
185                                          batadv_ogm_packet->tt_num_changes)) {
186                 /* we might have aggregated direct link packets with an
187                  * ordinary base packet
188                  */
189                 if (forw_packet->direct_link_flags & BIT(packet_num) &&
190                     forw_packet->if_incoming == hard_iface)
191                         batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
192                 else
193                         batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
194
195                 if (packet_num > 0 || !forw_packet->own)
196                         fwd_str = "Forwarding";
197                 else
198                         fwd_str = "Sending own";
199
200                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
201                            "%s %spacket (originator %pM, seqno %u, TQ %d, TTL %d, IDF %s, ttvn %d) on interface %s [%pM]\n",
202                            fwd_str, (packet_num > 0 ? "aggregated " : ""),
203                            batadv_ogm_packet->orig,
204                            ntohl(batadv_ogm_packet->seqno),
205                            batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl,
206                            (batadv_ogm_packet->flags & BATADV_DIRECTLINK ?
207                             "on" : "off"),
208                            batadv_ogm_packet->ttvn, hard_iface->net_dev->name,
209                            hard_iface->net_dev->dev_addr);
210
211                 buff_pos += BATADV_OGM_HLEN;
212                 buff_pos += batadv_tt_len(batadv_ogm_packet->tt_num_changes);
213                 packet_num++;
214                 packet_pos = forw_packet->skb->data + buff_pos;
215                 batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
216         }
217
218         /* create clone because function is called more than once */
219         skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
220         if (skb) {
221                 batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX);
222                 batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES,
223                                    skb->len + ETH_HLEN);
224                 batadv_send_skb_packet(skb, hard_iface, batadv_broadcast_addr);
225         }
226 }
227
228 /* send a batman ogm packet */
229 static void batadv_iv_ogm_emit(struct batadv_forw_packet *forw_packet)
230 {
231         struct batadv_hard_iface *hard_iface;
232         struct net_device *soft_iface;
233         struct batadv_priv *bat_priv;
234         struct batadv_hard_iface *primary_if = NULL;
235         struct batadv_ogm_packet *batadv_ogm_packet;
236         unsigned char directlink;
237         uint8_t *packet_pos;
238
239         packet_pos = forw_packet->skb->data;
240         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
241         directlink = (batadv_ogm_packet->flags & BATADV_DIRECTLINK ? 1 : 0);
242
243         if (!forw_packet->if_incoming) {
244                 pr_err("Error - can't forward packet: incoming iface not specified\n");
245                 goto out;
246         }
247
248         soft_iface = forw_packet->if_incoming->soft_iface;
249         bat_priv = netdev_priv(soft_iface);
250
251         if (forw_packet->if_incoming->if_status != BATADV_IF_ACTIVE)
252                 goto out;
253
254         primary_if = batadv_primary_if_get_selected(bat_priv);
255         if (!primary_if)
256                 goto out;
257
258         /* multihomed peer assumed
259          * non-primary OGMs are only broadcasted on their interface
260          */
261         if ((directlink && (batadv_ogm_packet->header.ttl == 1)) ||
262             (forw_packet->own && (forw_packet->if_incoming != primary_if))) {
263                 /* FIXME: what about aggregated packets ? */
264                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
265                            "%s packet (originator %pM, seqno %u, TTL %d) on interface %s [%pM]\n",
266                            (forw_packet->own ? "Sending own" : "Forwarding"),
267                            batadv_ogm_packet->orig,
268                            ntohl(batadv_ogm_packet->seqno),
269                            batadv_ogm_packet->header.ttl,
270                            forw_packet->if_incoming->net_dev->name,
271                            forw_packet->if_incoming->net_dev->dev_addr);
272
273                 /* skb is only used once and than forw_packet is free'd */
274                 batadv_send_skb_packet(forw_packet->skb,
275                                        forw_packet->if_incoming,
276                                        batadv_broadcast_addr);
277                 forw_packet->skb = NULL;
278
279                 goto out;
280         }
281
282         /* broadcast on every interface */
283         rcu_read_lock();
284         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
285                 if (hard_iface->soft_iface != soft_iface)
286                         continue;
287
288                 batadv_iv_ogm_send_to_if(forw_packet, hard_iface);
289         }
290         rcu_read_unlock();
291
292 out:
293         if (primary_if)
294                 batadv_hardif_free_ref(primary_if);
295 }
296
297 /* return true if new_packet can be aggregated with forw_packet */
298 static bool
299 batadv_iv_ogm_can_aggregate(const struct batadv_ogm_packet *new_bat_ogm_packet,
300                             struct batadv_priv *bat_priv,
301                             int packet_len, unsigned long send_time,
302                             bool directlink,
303                             const struct batadv_hard_iface *if_incoming,
304                             const struct batadv_forw_packet *forw_packet)
305 {
306         struct batadv_ogm_packet *batadv_ogm_packet;
307         int aggregated_bytes = forw_packet->packet_len + packet_len;
308         struct batadv_hard_iface *primary_if = NULL;
309         bool res = false;
310         unsigned long aggregation_end_time;
311
312         batadv_ogm_packet = (struct batadv_ogm_packet *)forw_packet->skb->data;
313         aggregation_end_time = send_time;
314         aggregation_end_time += msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
315
316         /* we can aggregate the current packet to this aggregated packet
317          * if:
318          *
319          * - the send time is within our MAX_AGGREGATION_MS time
320          * - the resulting packet wont be bigger than
321          *   MAX_AGGREGATION_BYTES
322          */
323         if (time_before(send_time, forw_packet->send_time) &&
324             time_after_eq(aggregation_end_time, forw_packet->send_time) &&
325             (aggregated_bytes <= BATADV_MAX_AGGREGATION_BYTES)) {
326                 /* check aggregation compatibility
327                  * -> direct link packets are broadcasted on
328                  *    their interface only
329                  * -> aggregate packet if the current packet is
330                  *    a "global" packet as well as the base
331                  *    packet
332                  */
333                 primary_if = batadv_primary_if_get_selected(bat_priv);
334                 if (!primary_if)
335                         goto out;
336
337                 /* packets without direct link flag and high TTL
338                  * are flooded through the net
339                  */
340                 if ((!directlink) &&
341                     (!(batadv_ogm_packet->flags & BATADV_DIRECTLINK)) &&
342                     (batadv_ogm_packet->header.ttl != 1) &&
343
344                     /* own packets originating non-primary
345                      * interfaces leave only that interface
346                      */
347                     ((!forw_packet->own) ||
348                      (forw_packet->if_incoming == primary_if))) {
349                         res = true;
350                         goto out;
351                 }
352
353                 /* if the incoming packet is sent via this one
354                  * interface only - we still can aggregate
355                  */
356                 if ((directlink) &&
357                     (new_bat_ogm_packet->header.ttl == 1) &&
358                     (forw_packet->if_incoming == if_incoming) &&
359
360                     /* packets from direct neighbors or
361                      * own secondary interface packets
362                      * (= secondary interface packets in general)
363                      */
364                     (batadv_ogm_packet->flags & BATADV_DIRECTLINK ||
365                      (forw_packet->own &&
366                       forw_packet->if_incoming != primary_if))) {
367                         res = true;
368                         goto out;
369                 }
370         }
371
372 out:
373         if (primary_if)
374                 batadv_hardif_free_ref(primary_if);
375         return res;
376 }
377
378 /* create a new aggregated packet and add this packet to it */
379 static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
380                                         int packet_len, unsigned long send_time,
381                                         bool direct_link,
382                                         struct batadv_hard_iface *if_incoming,
383                                         int own_packet)
384 {
385         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
386         struct batadv_forw_packet *forw_packet_aggr;
387         unsigned char *skb_buff;
388         unsigned int skb_size;
389
390         if (!atomic_inc_not_zero(&if_incoming->refcount))
391                 return;
392
393         /* own packet should always be scheduled */
394         if (!own_packet) {
395                 if (!batadv_atomic_dec_not_zero(&bat_priv->batman_queue_left)) {
396                         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
397                                    "batman packet queue full\n");
398                         goto out;
399                 }
400         }
401
402         forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC);
403         if (!forw_packet_aggr) {
404                 if (!own_packet)
405                         atomic_inc(&bat_priv->batman_queue_left);
406                 goto out;
407         }
408
409         if ((atomic_read(&bat_priv->aggregated_ogms)) &&
410             (packet_len < BATADV_MAX_AGGREGATION_BYTES))
411                 skb_size = BATADV_MAX_AGGREGATION_BYTES;
412         else
413                 skb_size = packet_len;
414
415         skb_size += ETH_HLEN + NET_IP_ALIGN;
416
417         forw_packet_aggr->skb = dev_alloc_skb(skb_size);
418         if (!forw_packet_aggr->skb) {
419                 if (!own_packet)
420                         atomic_inc(&bat_priv->batman_queue_left);
421                 kfree(forw_packet_aggr);
422                 goto out;
423         }
424         skb_reserve(forw_packet_aggr->skb, ETH_HLEN + NET_IP_ALIGN);
425
426         INIT_HLIST_NODE(&forw_packet_aggr->list);
427
428         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
429         forw_packet_aggr->packet_len = packet_len;
430         memcpy(skb_buff, packet_buff, packet_len);
431
432         forw_packet_aggr->own = own_packet;
433         forw_packet_aggr->if_incoming = if_incoming;
434         forw_packet_aggr->num_packets = 0;
435         forw_packet_aggr->direct_link_flags = BATADV_NO_FLAGS;
436         forw_packet_aggr->send_time = send_time;
437
438         /* save packet direct link flag status */
439         if (direct_link)
440                 forw_packet_aggr->direct_link_flags |= 1;
441
442         /* add new packet to packet list */
443         spin_lock_bh(&bat_priv->forw_bat_list_lock);
444         hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
445         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
446
447         /* start timer for this packet */
448         INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
449                           batadv_send_outstanding_bat_ogm_packet);
450         queue_delayed_work(batadv_event_workqueue,
451                            &forw_packet_aggr->delayed_work,
452                            send_time - jiffies);
453
454         return;
455 out:
456         batadv_hardif_free_ref(if_incoming);
457 }
458
459 /* aggregate a new packet into the existing ogm packet */
460 static void batadv_iv_ogm_aggregate(struct batadv_forw_packet *forw_packet_aggr,
461                                     const unsigned char *packet_buff,
462                                     int packet_len, bool direct_link)
463 {
464         unsigned char *skb_buff;
465         unsigned long new_direct_link_flag;
466
467         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
468         memcpy(skb_buff, packet_buff, packet_len);
469         forw_packet_aggr->packet_len += packet_len;
470         forw_packet_aggr->num_packets++;
471
472         /* save packet direct link flag status */
473         if (direct_link) {
474                 new_direct_link_flag = BIT(forw_packet_aggr->num_packets);
475                 forw_packet_aggr->direct_link_flags |= new_direct_link_flag;
476         }
477 }
478
479 static void batadv_iv_ogm_queue_add(struct batadv_priv *bat_priv,
480                                     unsigned char *packet_buff,
481                                     int packet_len,
482                                     struct batadv_hard_iface *if_incoming,
483                                     int own_packet, unsigned long send_time)
484 {
485         /* _aggr -> pointer to the packet we want to aggregate with
486          * _pos -> pointer to the position in the queue
487          */
488         struct batadv_forw_packet *forw_packet_aggr = NULL;
489         struct batadv_forw_packet *forw_packet_pos = NULL;
490         struct batadv_ogm_packet *batadv_ogm_packet;
491         bool direct_link;
492         unsigned long max_aggregation_jiffies;
493
494         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
495         direct_link = batadv_ogm_packet->flags & BATADV_DIRECTLINK ? 1 : 0;
496         max_aggregation_jiffies = msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
497
498         /* find position for the packet in the forward queue */
499         spin_lock_bh(&bat_priv->forw_bat_list_lock);
500         /* own packets are not to be aggregated */
501         if ((atomic_read(&bat_priv->aggregated_ogms)) && (!own_packet)) {
502                 hlist_for_each_entry(forw_packet_pos,
503                                      &bat_priv->forw_bat_list, list) {
504                         if (batadv_iv_ogm_can_aggregate(batadv_ogm_packet,
505                                                         bat_priv, packet_len,
506                                                         send_time, direct_link,
507                                                         if_incoming,
508                                                         forw_packet_pos)) {
509                                 forw_packet_aggr = forw_packet_pos;
510                                 break;
511                         }
512                 }
513         }
514
515         /* nothing to aggregate with - either aggregation disabled or no
516          * suitable aggregation packet found
517          */
518         if (!forw_packet_aggr) {
519                 /* the following section can run without the lock */
520                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
521
522                 /* if we could not aggregate this packet with one of the others
523                  * we hold it back for a while, so that it might be aggregated
524                  * later on
525                  */
526                 if (!own_packet && atomic_read(&bat_priv->aggregated_ogms))
527                         send_time += max_aggregation_jiffies;
528
529                 batadv_iv_ogm_aggregate_new(packet_buff, packet_len,
530                                             send_time, direct_link,
531                                             if_incoming, own_packet);
532         } else {
533                 batadv_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
534                                         packet_len, direct_link);
535                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
536         }
537 }
538
539 static void batadv_iv_ogm_forward(struct batadv_orig_node *orig_node,
540                                   const struct ethhdr *ethhdr,
541                                   struct batadv_ogm_packet *batadv_ogm_packet,
542                                   bool is_single_hop_neigh,
543                                   bool is_from_best_next_hop,
544                                   struct batadv_hard_iface *if_incoming)
545 {
546         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
547         uint8_t tt_num_changes;
548
549         if (batadv_ogm_packet->header.ttl <= 1) {
550                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n");
551                 return;
552         }
553
554         if (!is_from_best_next_hop) {
555                 /* Mark the forwarded packet when it is not coming from our
556                  * best next hop. We still need to forward the packet for our
557                  * neighbor link quality detection to work in case the packet
558                  * originated from a single hop neighbor. Otherwise we can
559                  * simply drop the ogm.
560                  */
561                 if (is_single_hop_neigh)
562                         batadv_ogm_packet->flags |= BATADV_NOT_BEST_NEXT_HOP;
563                 else
564                         return;
565         }
566
567         tt_num_changes = batadv_ogm_packet->tt_num_changes;
568
569         batadv_ogm_packet->header.ttl--;
570         memcpy(batadv_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
571
572         /* apply hop penalty */
573         batadv_ogm_packet->tq = batadv_hop_penalty(batadv_ogm_packet->tq,
574                                                    bat_priv);
575
576         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
577                    "Forwarding packet: tq: %i, ttl: %i\n",
578                    batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl);
579
580         /* switch of primaries first hop flag when forwarding */
581         batadv_ogm_packet->flags &= ~BATADV_PRIMARIES_FIRST_HOP;
582         if (is_single_hop_neigh)
583                 batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
584         else
585                 batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
586
587         batadv_iv_ogm_queue_add(bat_priv, (unsigned char *)batadv_ogm_packet,
588                                 BATADV_OGM_HLEN + batadv_tt_len(tt_num_changes),
589                                 if_incoming, 0, batadv_iv_ogm_fwd_send_time());
590 }
591
592 static void batadv_iv_ogm_schedule(struct batadv_hard_iface *hard_iface)
593 {
594         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
595         unsigned char **ogm_buff = &hard_iface->bat_iv.ogm_buff;
596         struct batadv_ogm_packet *batadv_ogm_packet;
597         struct batadv_hard_iface *primary_if;
598         int *ogm_buff_len = &hard_iface->bat_iv.ogm_buff_len;
599         int vis_server, tt_num_changes = 0;
600         uint32_t seqno;
601         uint8_t bandwidth;
602
603         vis_server = atomic_read(&bat_priv->vis_mode);
604         primary_if = batadv_primary_if_get_selected(bat_priv);
605
606         if (hard_iface == primary_if)
607                 tt_num_changes = batadv_tt_append_diff(bat_priv, ogm_buff,
608                                                        ogm_buff_len,
609                                                        BATADV_OGM_HLEN);
610
611         batadv_ogm_packet = (struct batadv_ogm_packet *)(*ogm_buff);
612
613         /* change sequence number to network order */
614         seqno = (uint32_t)atomic_read(&hard_iface->bat_iv.ogm_seqno);
615         batadv_ogm_packet->seqno = htonl(seqno);
616         atomic_inc(&hard_iface->bat_iv.ogm_seqno);
617
618         batadv_ogm_packet->ttvn = atomic_read(&bat_priv->tt.vn);
619         batadv_ogm_packet->tt_crc = htons(bat_priv->tt.local_crc);
620         if (tt_num_changes >= 0)
621                 batadv_ogm_packet->tt_num_changes = tt_num_changes;
622
623         if (vis_server == BATADV_VIS_TYPE_SERVER_SYNC)
624                 batadv_ogm_packet->flags |= BATADV_VIS_SERVER;
625         else
626                 batadv_ogm_packet->flags &= ~BATADV_VIS_SERVER;
627
628         if (hard_iface == primary_if &&
629             atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_SERVER) {
630                 bandwidth = (uint8_t)atomic_read(&bat_priv->gw_bandwidth);
631                 batadv_ogm_packet->gw_flags = bandwidth;
632         } else {
633                 batadv_ogm_packet->gw_flags = BATADV_NO_FLAGS;
634         }
635
636         batadv_slide_own_bcast_window(hard_iface);
637         batadv_iv_ogm_queue_add(bat_priv, hard_iface->bat_iv.ogm_buff,
638                                 hard_iface->bat_iv.ogm_buff_len, hard_iface, 1,
639                                 batadv_iv_ogm_emit_send_time(bat_priv));
640
641         if (primary_if)
642                 batadv_hardif_free_ref(primary_if);
643 }
644
645 static void
646 batadv_iv_ogm_orig_update(struct batadv_priv *bat_priv,
647                           struct batadv_orig_node *orig_node,
648                           const struct ethhdr *ethhdr,
649                           const struct batadv_ogm_packet *batadv_ogm_packet,
650                           struct batadv_hard_iface *if_incoming,
651                           const unsigned char *tt_buff,
652                           int is_duplicate)
653 {
654         struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
655         struct batadv_neigh_node *router = NULL;
656         struct batadv_orig_node *orig_node_tmp;
657         int if_num;
658         uint8_t sum_orig, sum_neigh;
659         uint8_t *neigh_addr;
660         uint8_t tq_avg;
661
662         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
663                    "update_originator(): Searching and updating originator entry of received packet\n");
664
665         rcu_read_lock();
666         hlist_for_each_entry_rcu(tmp_neigh_node,
667                                  &orig_node->neigh_list, list) {
668                 neigh_addr = tmp_neigh_node->addr;
669                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
670                     tmp_neigh_node->if_incoming == if_incoming &&
671                     atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
672                         if (neigh_node)
673                                 batadv_neigh_node_free_ref(neigh_node);
674                         neigh_node = tmp_neigh_node;
675                         continue;
676                 }
677
678                 if (is_duplicate)
679                         continue;
680
681                 spin_lock_bh(&tmp_neigh_node->lq_update_lock);
682                 batadv_ring_buffer_set(tmp_neigh_node->tq_recv,
683                                        &tmp_neigh_node->tq_index, 0);
684                 tq_avg = batadv_ring_buffer_avg(tmp_neigh_node->tq_recv);
685                 tmp_neigh_node->tq_avg = tq_avg;
686                 spin_unlock_bh(&tmp_neigh_node->lq_update_lock);
687         }
688
689         if (!neigh_node) {
690                 struct batadv_orig_node *orig_tmp;
691
692                 orig_tmp = batadv_get_orig_node(bat_priv, ethhdr->h_source);
693                 if (!orig_tmp)
694                         goto unlock;
695
696                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
697                                                      ethhdr->h_source,
698                                                      orig_node, orig_tmp,
699                                                      batadv_ogm_packet->seqno);
700
701                 batadv_orig_node_free_ref(orig_tmp);
702                 if (!neigh_node)
703                         goto unlock;
704         } else
705                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
706                            "Updating existing last-hop neighbor of originator\n");
707
708         rcu_read_unlock();
709
710         orig_node->flags = batadv_ogm_packet->flags;
711         neigh_node->last_seen = jiffies;
712
713         spin_lock_bh(&neigh_node->lq_update_lock);
714         batadv_ring_buffer_set(neigh_node->tq_recv,
715                                &neigh_node->tq_index,
716                                batadv_ogm_packet->tq);
717         neigh_node->tq_avg = batadv_ring_buffer_avg(neigh_node->tq_recv);
718         spin_unlock_bh(&neigh_node->lq_update_lock);
719
720         if (!is_duplicate) {
721                 orig_node->last_ttl = batadv_ogm_packet->header.ttl;
722                 neigh_node->last_ttl = batadv_ogm_packet->header.ttl;
723         }
724
725         batadv_bonding_candidate_add(orig_node, neigh_node);
726
727         /* if this neighbor already is our next hop there is nothing
728          * to change
729          */
730         router = batadv_orig_node_get_router(orig_node);
731         if (router == neigh_node)
732                 goto update_tt;
733
734         /* if this neighbor does not offer a better TQ we won't consider it */
735         if (router && (router->tq_avg > neigh_node->tq_avg))
736                 goto update_tt;
737
738         /* if the TQ is the same and the link not more symmetric we
739          * won't consider it either
740          */
741         if (router && (neigh_node->tq_avg == router->tq_avg)) {
742                 orig_node_tmp = router->orig_node;
743                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
744                 if_num = router->if_incoming->if_num;
745                 sum_orig = orig_node_tmp->bcast_own_sum[if_num];
746                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
747
748                 orig_node_tmp = neigh_node->orig_node;
749                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
750                 if_num = neigh_node->if_incoming->if_num;
751                 sum_neigh = orig_node_tmp->bcast_own_sum[if_num];
752                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
753
754                 if (sum_orig >= sum_neigh)
755                         goto update_tt;
756         }
757
758         batadv_update_route(bat_priv, orig_node, neigh_node);
759
760 update_tt:
761         /* I have to check for transtable changes only if the OGM has been
762          * sent through a primary interface
763          */
764         if (((batadv_ogm_packet->orig != ethhdr->h_source) &&
765              (batadv_ogm_packet->header.ttl > 2)) ||
766             (batadv_ogm_packet->flags & BATADV_PRIMARIES_FIRST_HOP))
767                 batadv_tt_update_orig(bat_priv, orig_node, tt_buff,
768                                       batadv_ogm_packet->tt_num_changes,
769                                       batadv_ogm_packet->ttvn,
770                                       ntohs(batadv_ogm_packet->tt_crc));
771
772         if (orig_node->gw_flags != batadv_ogm_packet->gw_flags)
773                 batadv_gw_node_update(bat_priv, orig_node,
774                                       batadv_ogm_packet->gw_flags);
775
776         orig_node->gw_flags = batadv_ogm_packet->gw_flags;
777
778         /* restart gateway selection if fast or late switching was enabled */
779         if ((orig_node->gw_flags) &&
780             (atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_CLIENT) &&
781             (atomic_read(&bat_priv->gw_sel_class) > 2))
782                 batadv_gw_check_election(bat_priv, orig_node);
783
784         goto out;
785
786 unlock:
787         rcu_read_unlock();
788 out:
789         if (neigh_node)
790                 batadv_neigh_node_free_ref(neigh_node);
791         if (router)
792                 batadv_neigh_node_free_ref(router);
793 }
794
795 static int batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node,
796                                  struct batadv_orig_node *orig_neigh_node,
797                                  struct batadv_ogm_packet *batadv_ogm_packet,
798                                  struct batadv_hard_iface *if_incoming)
799 {
800         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
801         struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node;
802         uint8_t total_count;
803         uint8_t orig_eq_count, neigh_rq_count, neigh_rq_inv, tq_own;
804         unsigned int neigh_rq_inv_cube, neigh_rq_max_cube;
805         int tq_asym_penalty, inv_asym_penalty, ret = 0;
806         unsigned int combined_tq;
807
808         /* find corresponding one hop neighbor */
809         rcu_read_lock();
810         hlist_for_each_entry_rcu(tmp_neigh_node,
811                                  &orig_neigh_node->neigh_list, list) {
812                 if (!batadv_compare_eth(tmp_neigh_node->addr,
813                                         orig_neigh_node->orig))
814                         continue;
815
816                 if (tmp_neigh_node->if_incoming != if_incoming)
817                         continue;
818
819                 if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
820                         continue;
821
822                 neigh_node = tmp_neigh_node;
823                 break;
824         }
825         rcu_read_unlock();
826
827         if (!neigh_node)
828                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
829                                                      orig_neigh_node->orig,
830                                                      orig_neigh_node,
831                                                      orig_neigh_node,
832                                                      batadv_ogm_packet->seqno);
833
834         if (!neigh_node)
835                 goto out;
836
837         /* if orig_node is direct neighbor update neigh_node last_seen */
838         if (orig_node == orig_neigh_node)
839                 neigh_node->last_seen = jiffies;
840
841         orig_node->last_seen = jiffies;
842
843         /* find packet count of corresponding one hop neighbor */
844         spin_lock_bh(&orig_node->ogm_cnt_lock);
845         orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num];
846         neigh_rq_count = neigh_node->real_packet_count;
847         spin_unlock_bh(&orig_node->ogm_cnt_lock);
848
849         /* pay attention to not get a value bigger than 100 % */
850         if (orig_eq_count > neigh_rq_count)
851                 total_count = neigh_rq_count;
852         else
853                 total_count = orig_eq_count;
854
855         /* if we have too few packets (too less data) we set tq_own to zero
856          * if we receive too few packets it is not considered bidirectional
857          */
858         if (total_count < BATADV_TQ_LOCAL_BIDRECT_SEND_MINIMUM ||
859             neigh_rq_count < BATADV_TQ_LOCAL_BIDRECT_RECV_MINIMUM)
860                 tq_own = 0;
861         else
862                 /* neigh_node->real_packet_count is never zero as we
863                  * only purge old information when getting new
864                  * information
865                  */
866                 tq_own = (BATADV_TQ_MAX_VALUE * total_count) /  neigh_rq_count;
867
868         /* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
869          * affect the nearly-symmetric links only a little, but
870          * punishes asymmetric links more.  This will give a value
871          * between 0 and TQ_MAX_VALUE
872          */
873         neigh_rq_inv = BATADV_TQ_LOCAL_WINDOW_SIZE - neigh_rq_count;
874         neigh_rq_inv_cube = neigh_rq_inv * neigh_rq_inv * neigh_rq_inv;
875         neigh_rq_max_cube = BATADV_TQ_LOCAL_WINDOW_SIZE *
876                             BATADV_TQ_LOCAL_WINDOW_SIZE *
877                             BATADV_TQ_LOCAL_WINDOW_SIZE;
878         inv_asym_penalty = BATADV_TQ_MAX_VALUE * neigh_rq_inv_cube;
879         inv_asym_penalty /= neigh_rq_max_cube;
880         tq_asym_penalty = BATADV_TQ_MAX_VALUE - inv_asym_penalty;
881
882         combined_tq = batadv_ogm_packet->tq * tq_own * tq_asym_penalty;
883         combined_tq /= BATADV_TQ_MAX_VALUE * BATADV_TQ_MAX_VALUE;
884         batadv_ogm_packet->tq = combined_tq;
885
886         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
887                    "bidirectional: orig = %-15pM neigh = %-15pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, total tq: %3i\n",
888                    orig_node->orig, orig_neigh_node->orig, total_count,
889                    neigh_rq_count, tq_own,
890                    tq_asym_penalty, batadv_ogm_packet->tq);
891
892         /* if link has the minimum required transmission quality
893          * consider it bidirectional
894          */
895         if (batadv_ogm_packet->tq >= BATADV_TQ_TOTAL_BIDRECT_LIMIT)
896                 ret = 1;
897
898 out:
899         if (neigh_node)
900                 batadv_neigh_node_free_ref(neigh_node);
901         return ret;
902 }
903
904 /* processes a batman packet for all interfaces, adjusts the sequence number and
905  * finds out whether it is a duplicate.
906  * returns:
907  *   1 the packet is a duplicate
908  *   0 the packet has not yet been received
909  *  -1 the packet is old and has been received while the seqno window
910  *     was protected. Caller should drop it.
911  */
912 static int
913 batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
914                             const struct batadv_ogm_packet *batadv_ogm_packet,
915                             const struct batadv_hard_iface *if_incoming)
916 {
917         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
918         struct batadv_orig_node *orig_node;
919         struct batadv_neigh_node *tmp_neigh_node;
920         int is_duplicate = 0;
921         int32_t seq_diff;
922         int need_update = 0;
923         int set_mark, ret = -1;
924         uint32_t seqno = ntohl(batadv_ogm_packet->seqno);
925         uint8_t *neigh_addr;
926         uint8_t packet_count;
927
928         orig_node = batadv_get_orig_node(bat_priv, batadv_ogm_packet->orig);
929         if (!orig_node)
930                 return 0;
931
932         spin_lock_bh(&orig_node->ogm_cnt_lock);
933         seq_diff = seqno - orig_node->last_real_seqno;
934
935         /* signalize caller that the packet is to be dropped. */
936         if (!hlist_empty(&orig_node->neigh_list) &&
937             batadv_window_protected(bat_priv, seq_diff,
938                                     &orig_node->batman_seqno_reset))
939                 goto out;
940
941         rcu_read_lock();
942         hlist_for_each_entry_rcu(tmp_neigh_node,
943                                  &orig_node->neigh_list, list) {
944                 is_duplicate |= batadv_test_bit(tmp_neigh_node->real_bits,
945                                                 orig_node->last_real_seqno,
946                                                 seqno);
947
948                 neigh_addr = tmp_neigh_node->addr;
949                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
950                     tmp_neigh_node->if_incoming == if_incoming)
951                         set_mark = 1;
952                 else
953                         set_mark = 0;
954
955                 /* if the window moved, set the update flag. */
956                 need_update |= batadv_bit_get_packet(bat_priv,
957                                                      tmp_neigh_node->real_bits,
958                                                      seq_diff, set_mark);
959
960                 packet_count = bitmap_weight(tmp_neigh_node->real_bits,
961                                              BATADV_TQ_LOCAL_WINDOW_SIZE);
962                 tmp_neigh_node->real_packet_count = packet_count;
963         }
964         rcu_read_unlock();
965
966         if (need_update) {
967                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
968                            "updating last_seqno: old %u, new %u\n",
969                            orig_node->last_real_seqno, seqno);
970                 orig_node->last_real_seqno = seqno;
971         }
972
973         ret = is_duplicate;
974
975 out:
976         spin_unlock_bh(&orig_node->ogm_cnt_lock);
977         batadv_orig_node_free_ref(orig_node);
978         return ret;
979 }
980
981 static void batadv_iv_ogm_process(const struct ethhdr *ethhdr,
982                                   struct batadv_ogm_packet *batadv_ogm_packet,
983                                   const unsigned char *tt_buff,
984                                   struct batadv_hard_iface *if_incoming)
985 {
986         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
987         struct batadv_hard_iface *hard_iface;
988         struct batadv_orig_node *orig_neigh_node, *orig_node;
989         struct batadv_neigh_node *router = NULL, *router_router = NULL;
990         struct batadv_neigh_node *orig_neigh_router = NULL;
991         int has_directlink_flag;
992         int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
993         int is_broadcast = 0, is_bidirect;
994         bool is_single_hop_neigh = false;
995         bool is_from_best_next_hop = false;
996         int is_duplicate, sameseq, simlar_ttl;
997         uint32_t if_incoming_seqno;
998         uint8_t *prev_sender;
999
1000         /* Silently drop when the batman packet is actually not a
1001          * correct packet.
1002          *
1003          * This might happen if a packet is padded (e.g. Ethernet has a
1004          * minimum frame length of 64 byte) and the aggregation interprets
1005          * it as an additional length.
1006          *
1007          * TODO: A more sane solution would be to have a bit in the
1008          * batadv_ogm_packet to detect whether the packet is the last
1009          * packet in an aggregation.  Here we expect that the padding
1010          * is always zero (or not 0x01)
1011          */
1012         if (batadv_ogm_packet->header.packet_type != BATADV_IV_OGM)
1013                 return;
1014
1015         /* could be changed by schedule_own_packet() */
1016         if_incoming_seqno = atomic_read(&if_incoming->bat_iv.ogm_seqno);
1017
1018         if (batadv_ogm_packet->flags & BATADV_DIRECTLINK)
1019                 has_directlink_flag = 1;
1020         else
1021                 has_directlink_flag = 0;
1022
1023         if (batadv_compare_eth(ethhdr->h_source, batadv_ogm_packet->orig))
1024                 is_single_hop_neigh = true;
1025
1026         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1027                    "Received BATMAN packet via NB: %pM, IF: %s [%pM] (from OG: %pM, via prev OG: %pM, seqno %u, ttvn %u, crc %#.4x, changes %u, tq %d, TTL %d, V %d, IDF %d)\n",
1028                    ethhdr->h_source, if_incoming->net_dev->name,
1029                    if_incoming->net_dev->dev_addr, batadv_ogm_packet->orig,
1030                    batadv_ogm_packet->prev_sender,
1031                    ntohl(batadv_ogm_packet->seqno), batadv_ogm_packet->ttvn,
1032                    ntohs(batadv_ogm_packet->tt_crc),
1033                    batadv_ogm_packet->tt_num_changes, batadv_ogm_packet->tq,
1034                    batadv_ogm_packet->header.ttl,
1035                    batadv_ogm_packet->header.version, has_directlink_flag);
1036
1037         rcu_read_lock();
1038         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
1039                 if (hard_iface->if_status != BATADV_IF_ACTIVE)
1040                         continue;
1041
1042                 if (hard_iface->soft_iface != if_incoming->soft_iface)
1043                         continue;
1044
1045                 if (batadv_compare_eth(ethhdr->h_source,
1046                                        hard_iface->net_dev->dev_addr))
1047                         is_my_addr = 1;
1048
1049                 if (batadv_compare_eth(batadv_ogm_packet->orig,
1050                                        hard_iface->net_dev->dev_addr))
1051                         is_my_orig = 1;
1052
1053                 if (batadv_compare_eth(batadv_ogm_packet->prev_sender,
1054                                        hard_iface->net_dev->dev_addr))
1055                         is_my_oldorig = 1;
1056
1057                 if (is_broadcast_ether_addr(ethhdr->h_source))
1058                         is_broadcast = 1;
1059         }
1060         rcu_read_unlock();
1061
1062         if (batadv_ogm_packet->header.version != BATADV_COMPAT_VERSION) {
1063                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1064                            "Drop packet: incompatible batman version (%i)\n",
1065                            batadv_ogm_packet->header.version);
1066                 return;
1067         }
1068
1069         if (is_my_addr) {
1070                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1071                            "Drop packet: received my own broadcast (sender: %pM)\n",
1072                            ethhdr->h_source);
1073                 return;
1074         }
1075
1076         if (is_broadcast) {
1077                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1078                            "Drop packet: ignoring all packets with broadcast source addr (sender: %pM)\n",
1079                            ethhdr->h_source);
1080                 return;
1081         }
1082
1083         if (is_my_orig) {
1084                 unsigned long *word;
1085                 int offset;
1086                 int32_t bit_pos;
1087                 int16_t if_num;
1088                 uint8_t *weight;
1089
1090                 orig_neigh_node = batadv_get_orig_node(bat_priv,
1091                                                        ethhdr->h_source);
1092                 if (!orig_neigh_node)
1093                         return;
1094
1095                 /* neighbor has to indicate direct link and it has to
1096                  * come via the corresponding interface
1097                  * save packet seqno for bidirectional check
1098                  */
1099                 if (has_directlink_flag &&
1100                     batadv_compare_eth(if_incoming->net_dev->dev_addr,
1101                                        batadv_ogm_packet->orig)) {
1102                         if_num = if_incoming->if_num;
1103                         offset = if_num * BATADV_NUM_WORDS;
1104
1105                         spin_lock_bh(&orig_neigh_node->ogm_cnt_lock);
1106                         word = &(orig_neigh_node->bcast_own[offset]);
1107                         bit_pos = if_incoming_seqno - 2;
1108                         bit_pos -= ntohl(batadv_ogm_packet->seqno);
1109                         batadv_set_bit(word, bit_pos);
1110                         weight = &orig_neigh_node->bcast_own_sum[if_num];
1111                         *weight = bitmap_weight(word,
1112                                                 BATADV_TQ_LOCAL_WINDOW_SIZE);
1113                         spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);
1114                 }
1115
1116                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1117                            "Drop packet: originator packet from myself (via neighbor)\n");
1118                 batadv_orig_node_free_ref(orig_neigh_node);
1119                 return;
1120         }
1121
1122         if (is_my_oldorig) {
1123                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1124                            "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
1125                            ethhdr->h_source);
1126                 return;
1127         }
1128
1129         if (batadv_ogm_packet->flags & BATADV_NOT_BEST_NEXT_HOP) {
1130                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1131                            "Drop packet: ignoring all packets not forwarded from the best next hop (sender: %pM)\n",
1132                            ethhdr->h_source);
1133                 return;
1134         }
1135
1136         orig_node = batadv_get_orig_node(bat_priv, batadv_ogm_packet->orig);
1137         if (!orig_node)
1138                 return;
1139
1140         is_duplicate = batadv_iv_ogm_update_seqnos(ethhdr, batadv_ogm_packet,
1141                                                    if_incoming);
1142
1143         if (is_duplicate == -1) {
1144                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1145                            "Drop packet: packet within seqno protection time (sender: %pM)\n",
1146                            ethhdr->h_source);
1147                 goto out;
1148         }
1149
1150         if (batadv_ogm_packet->tq == 0) {
1151                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1152                            "Drop packet: originator packet with tq equal 0\n");
1153                 goto out;
1154         }
1155
1156         router = batadv_orig_node_get_router(orig_node);
1157         if (router)
1158                 router_router = batadv_orig_node_get_router(router->orig_node);
1159
1160         if ((router && router->tq_avg != 0) &&
1161             (batadv_compare_eth(router->addr, ethhdr->h_source)))
1162                 is_from_best_next_hop = true;
1163
1164         prev_sender = batadv_ogm_packet->prev_sender;
1165         /* avoid temporary routing loops */
1166         if (router && router_router &&
1167             (batadv_compare_eth(router->addr, prev_sender)) &&
1168             !(batadv_compare_eth(batadv_ogm_packet->orig, prev_sender)) &&
1169             (batadv_compare_eth(router->addr, router_router->addr))) {
1170                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1171                            "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
1172                            ethhdr->h_source);
1173                 goto out;
1174         }
1175
1176         /* if sender is a direct neighbor the sender mac equals
1177          * originator mac
1178          */
1179         if (is_single_hop_neigh)
1180                 orig_neigh_node = orig_node;
1181         else
1182                 orig_neigh_node = batadv_get_orig_node(bat_priv,
1183                                                        ethhdr->h_source);
1184
1185         if (!orig_neigh_node)
1186                 goto out;
1187
1188         orig_neigh_router = batadv_orig_node_get_router(orig_neigh_node);
1189
1190         /* drop packet if sender is not a direct neighbor and if we
1191          * don't route towards it
1192          */
1193         if (!is_single_hop_neigh && (!orig_neigh_router)) {
1194                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1195                            "Drop packet: OGM via unknown neighbor!\n");
1196                 goto out_neigh;
1197         }
1198
1199         is_bidirect = batadv_iv_ogm_calc_tq(orig_node, orig_neigh_node,
1200                                             batadv_ogm_packet, if_incoming);
1201
1202         batadv_bonding_save_primary(orig_node, orig_neigh_node,
1203                                     batadv_ogm_packet);
1204
1205         /* update ranking if it is not a duplicate or has the same
1206          * seqno and similar ttl as the non-duplicate
1207          */
1208         sameseq = orig_node->last_real_seqno == ntohl(batadv_ogm_packet->seqno);
1209         simlar_ttl = orig_node->last_ttl - 3 <= batadv_ogm_packet->header.ttl;
1210         if (is_bidirect && (!is_duplicate || (sameseq && simlar_ttl)))
1211                 batadv_iv_ogm_orig_update(bat_priv, orig_node, ethhdr,
1212                                           batadv_ogm_packet, if_incoming,
1213                                           tt_buff, is_duplicate);
1214
1215         /* is single hop (direct) neighbor */
1216         if (is_single_hop_neigh) {
1217                 /* mark direct link on incoming interface */
1218                 batadv_iv_ogm_forward(orig_node, ethhdr, batadv_ogm_packet,
1219                                       is_single_hop_neigh,
1220                                       is_from_best_next_hop, if_incoming);
1221
1222                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1223                            "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
1224                 goto out_neigh;
1225         }
1226
1227         /* multihop originator */
1228         if (!is_bidirect) {
1229                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1230                            "Drop packet: not received via bidirectional link\n");
1231                 goto out_neigh;
1232         }
1233
1234         if (is_duplicate) {
1235                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1236                            "Drop packet: duplicate packet received\n");
1237                 goto out_neigh;
1238         }
1239
1240         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1241                    "Forwarding packet: rebroadcast originator packet\n");
1242         batadv_iv_ogm_forward(orig_node, ethhdr, batadv_ogm_packet,
1243                               is_single_hop_neigh, is_from_best_next_hop,
1244                               if_incoming);
1245
1246 out_neigh:
1247         if ((orig_neigh_node) && (!is_single_hop_neigh))
1248                 batadv_orig_node_free_ref(orig_neigh_node);
1249 out:
1250         if (router)
1251                 batadv_neigh_node_free_ref(router);
1252         if (router_router)
1253                 batadv_neigh_node_free_ref(router_router);
1254         if (orig_neigh_router)
1255                 batadv_neigh_node_free_ref(orig_neigh_router);
1256
1257         batadv_orig_node_free_ref(orig_node);
1258 }
1259
1260 static int batadv_iv_ogm_receive(struct sk_buff *skb,
1261                                  struct batadv_hard_iface *if_incoming)
1262 {
1263         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1264         struct batadv_ogm_packet *batadv_ogm_packet;
1265         struct ethhdr *ethhdr;
1266         int buff_pos = 0, packet_len;
1267         unsigned char *tt_buff, *packet_buff;
1268         bool ret;
1269         uint8_t *packet_pos;
1270
1271         ret = batadv_check_management_packet(skb, if_incoming, BATADV_OGM_HLEN);
1272         if (!ret)
1273                 return NET_RX_DROP;
1274
1275         /* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
1276          * that does not have B.A.T.M.A.N. IV enabled ?
1277          */
1278         if (bat_priv->bat_algo_ops->bat_ogm_emit != batadv_iv_ogm_emit)
1279                 return NET_RX_DROP;
1280
1281         batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX);
1282         batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES,
1283                            skb->len + ETH_HLEN);
1284
1285         packet_len = skb_headlen(skb);
1286         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1287         packet_buff = skb->data;
1288         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
1289
1290         /* unpack the aggregated packets and process them one by one */
1291         while (batadv_iv_ogm_aggr_packet(buff_pos, packet_len,
1292                                          batadv_ogm_packet->tt_num_changes)) {
1293                 tt_buff = packet_buff + buff_pos + BATADV_OGM_HLEN;
1294
1295                 batadv_iv_ogm_process(ethhdr, batadv_ogm_packet, tt_buff,
1296                                       if_incoming);
1297
1298                 buff_pos += BATADV_OGM_HLEN;
1299                 buff_pos += batadv_tt_len(batadv_ogm_packet->tt_num_changes);
1300
1301                 packet_pos = packet_buff + buff_pos;
1302                 batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
1303         }
1304
1305         kfree_skb(skb);
1306         return NET_RX_SUCCESS;
1307 }
1308
1309 static struct batadv_algo_ops batadv_batman_iv __read_mostly = {
1310         .name = "BATMAN_IV",
1311         .bat_iface_enable = batadv_iv_ogm_iface_enable,
1312         .bat_iface_disable = batadv_iv_ogm_iface_disable,
1313         .bat_iface_update_mac = batadv_iv_ogm_iface_update_mac,
1314         .bat_primary_iface_set = batadv_iv_ogm_primary_iface_set,
1315         .bat_ogm_schedule = batadv_iv_ogm_schedule,
1316         .bat_ogm_emit = batadv_iv_ogm_emit,
1317 };
1318
1319 int __init batadv_iv_init(void)
1320 {
1321         int ret;
1322
1323         /* batman originator packet */
1324         ret = batadv_recv_handler_register(BATADV_IV_OGM,
1325                                            batadv_iv_ogm_receive);
1326         if (ret < 0)
1327                 goto out;
1328
1329         ret = batadv_algo_register(&batadv_batman_iv);
1330         if (ret < 0)
1331                 goto handler_unregister;
1332
1333         goto out;
1334
1335 handler_unregister:
1336         batadv_recv_handler_unregister(BATADV_IV_OGM);
1337 out:
1338         return ret;
1339 }