Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
[pandora-kernel.git] / net / batman-adv / bat_iv_ogm.c
1 /*
2  * Copyright (C) 2007-2011 B.A.T.M.A.N. contributors:
3  *
4  * Marek Lindner, Simon Wunderlich
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of version 2 of the GNU General Public
8  * License as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  * General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
18  * 02110-1301, USA
19  *
20  */
21
22 #include "main.h"
23 #include "bat_ogm.h"
24 #include "translation-table.h"
25 #include "ring_buffer.h"
26 #include "originator.h"
27 #include "routing.h"
28 #include "gateway_common.h"
29 #include "gateway_client.h"
30 #include "hard-interface.h"
31 #include "send.h"
32
33 void bat_ogm_init(struct hard_iface *hard_iface)
34 {
35         struct batman_ogm_packet *batman_ogm_packet;
36
37         hard_iface->packet_len = BATMAN_OGM_LEN;
38         hard_iface->packet_buff = kmalloc(hard_iface->packet_len, GFP_ATOMIC);
39
40         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
41         batman_ogm_packet->packet_type = BAT_OGM;
42         batman_ogm_packet->version = COMPAT_VERSION;
43         batman_ogm_packet->flags = NO_FLAGS;
44         batman_ogm_packet->ttl = 2;
45         batman_ogm_packet->tq = TQ_MAX_VALUE;
46         batman_ogm_packet->tt_num_changes = 0;
47         batman_ogm_packet->ttvn = 0;
48 }
49
50 void bat_ogm_init_primary(struct hard_iface *hard_iface)
51 {
52         struct batman_ogm_packet *batman_ogm_packet;
53
54         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
55         batman_ogm_packet->flags = PRIMARIES_FIRST_HOP;
56         batman_ogm_packet->ttl = TTL;
57 }
58
59 void bat_ogm_update_mac(struct hard_iface *hard_iface)
60 {
61         struct batman_ogm_packet *batman_ogm_packet;
62
63         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
64         memcpy(batman_ogm_packet->orig,
65                hard_iface->net_dev->dev_addr, ETH_ALEN);
66         memcpy(batman_ogm_packet->prev_sender,
67                hard_iface->net_dev->dev_addr, ETH_ALEN);
68 }
69
70 /* when do we schedule our own ogm to be sent */
71 static unsigned long bat_ogm_emit_send_time(const struct bat_priv *bat_priv)
72 {
73         return jiffies + msecs_to_jiffies(
74                    atomic_read(&bat_priv->orig_interval) -
75                    JITTER + (random32() % 2*JITTER));
76 }
77
78 /* when do we schedule a ogm packet to be sent */
79 static unsigned long bat_ogm_fwd_send_time(void)
80 {
81         return jiffies + msecs_to_jiffies(random32() % (JITTER/2));
82 }
83
84 /* apply hop penalty for a normal link */
85 static uint8_t hop_penalty(uint8_t tq, const struct bat_priv *bat_priv)
86 {
87         int hop_penalty = atomic_read(&bat_priv->hop_penalty);
88         return (tq * (TQ_MAX_VALUE - hop_penalty)) / (TQ_MAX_VALUE);
89 }
90
91 /* is there another aggregated packet here? */
92 static int bat_ogm_aggr_packet(int buff_pos, int packet_len,
93                                int tt_num_changes)
94 {
95         int next_buff_pos = buff_pos + BATMAN_OGM_LEN + tt_len(tt_num_changes);
96
97         return (next_buff_pos <= packet_len) &&
98                 (next_buff_pos <= MAX_AGGREGATION_BYTES);
99 }
100
101 /* send a batman ogm to a given interface */
102 static void bat_ogm_send_to_if(struct forw_packet *forw_packet,
103                                struct hard_iface *hard_iface)
104 {
105         struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
106         char *fwd_str;
107         uint8_t packet_num;
108         int16_t buff_pos;
109         struct batman_ogm_packet *batman_ogm_packet;
110         struct sk_buff *skb;
111
112         if (hard_iface->if_status != IF_ACTIVE)
113                 return;
114
115         packet_num = 0;
116         buff_pos = 0;
117         batman_ogm_packet = (struct batman_ogm_packet *)forw_packet->skb->data;
118
119         /* adjust all flags and log packets */
120         while (bat_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
121                                    batman_ogm_packet->tt_num_changes)) {
122
123                 /* we might have aggregated direct link packets with an
124                  * ordinary base packet */
125                 if ((forw_packet->direct_link_flags & (1 << packet_num)) &&
126                     (forw_packet->if_incoming == hard_iface))
127                         batman_ogm_packet->flags |= DIRECTLINK;
128                 else
129                         batman_ogm_packet->flags &= ~DIRECTLINK;
130
131                 fwd_str = (packet_num > 0 ? "Forwarding" : (forw_packet->own ?
132                                                             "Sending own" :
133                                                             "Forwarding"));
134                 bat_dbg(DBG_BATMAN, bat_priv,
135                         "%s %spacket (originator %pM, seqno %d, TQ %d, TTL %d,"
136                         " IDF %s, ttvn %d) on interface %s [%pM]\n",
137                         fwd_str, (packet_num > 0 ? "aggregated " : ""),
138                         batman_ogm_packet->orig,
139                         ntohl(batman_ogm_packet->seqno),
140                         batman_ogm_packet->tq, batman_ogm_packet->ttl,
141                         (batman_ogm_packet->flags & DIRECTLINK ?
142                          "on" : "off"),
143                         batman_ogm_packet->ttvn, hard_iface->net_dev->name,
144                         hard_iface->net_dev->dev_addr);
145
146                 buff_pos += BATMAN_OGM_LEN +
147                                 tt_len(batman_ogm_packet->tt_num_changes);
148                 packet_num++;
149                 batman_ogm_packet = (struct batman_ogm_packet *)
150                                         (forw_packet->skb->data + buff_pos);
151         }
152
153         /* create clone because function is called more than once */
154         skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
155         if (skb)
156                 send_skb_packet(skb, hard_iface, broadcast_addr);
157 }
158
159 /* send a batman ogm packet */
160 void bat_ogm_emit(struct forw_packet *forw_packet)
161 {
162         struct hard_iface *hard_iface;
163         struct net_device *soft_iface;
164         struct bat_priv *bat_priv;
165         struct hard_iface *primary_if = NULL;
166         struct batman_ogm_packet *batman_ogm_packet;
167         unsigned char directlink;
168
169         batman_ogm_packet = (struct batman_ogm_packet *)
170                                                 (forw_packet->skb->data);
171         directlink = (batman_ogm_packet->flags & DIRECTLINK ? 1 : 0);
172
173         if (!forw_packet->if_incoming) {
174                 pr_err("Error - can't forward packet: incoming iface not "
175                        "specified\n");
176                 goto out;
177         }
178
179         soft_iface = forw_packet->if_incoming->soft_iface;
180         bat_priv = netdev_priv(soft_iface);
181
182         if (forw_packet->if_incoming->if_status != IF_ACTIVE)
183                 goto out;
184
185         primary_if = primary_if_get_selected(bat_priv);
186         if (!primary_if)
187                 goto out;
188
189         /* multihomed peer assumed */
190         /* non-primary OGMs are only broadcasted on their interface */
191         if ((directlink && (batman_ogm_packet->ttl == 1)) ||
192             (forw_packet->own && (forw_packet->if_incoming != primary_if))) {
193
194                 /* FIXME: what about aggregated packets ? */
195                 bat_dbg(DBG_BATMAN, bat_priv,
196                         "%s packet (originator %pM, seqno %d, TTL %d) "
197                         "on interface %s [%pM]\n",
198                         (forw_packet->own ? "Sending own" : "Forwarding"),
199                         batman_ogm_packet->orig,
200                         ntohl(batman_ogm_packet->seqno),
201                         batman_ogm_packet->ttl,
202                         forw_packet->if_incoming->net_dev->name,
203                         forw_packet->if_incoming->net_dev->dev_addr);
204
205                 /* skb is only used once and than forw_packet is free'd */
206                 send_skb_packet(forw_packet->skb, forw_packet->if_incoming,
207                                 broadcast_addr);
208                 forw_packet->skb = NULL;
209
210                 goto out;
211         }
212
213         /* broadcast on every interface */
214         rcu_read_lock();
215         list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
216                 if (hard_iface->soft_iface != soft_iface)
217                         continue;
218
219                 bat_ogm_send_to_if(forw_packet, hard_iface);
220         }
221         rcu_read_unlock();
222
223 out:
224         if (primary_if)
225                 hardif_free_ref(primary_if);
226 }
227
228 /* return true if new_packet can be aggregated with forw_packet */
229 static bool bat_ogm_can_aggregate(const struct batman_ogm_packet
230                                                         *new_batman_ogm_packet,
231                                   struct bat_priv *bat_priv,
232                                   int packet_len, unsigned long send_time,
233                                   bool directlink,
234                                   const struct hard_iface *if_incoming,
235                                   const struct forw_packet *forw_packet)
236 {
237         struct batman_ogm_packet *batman_ogm_packet;
238         int aggregated_bytes = forw_packet->packet_len + packet_len;
239         struct hard_iface *primary_if = NULL;
240         bool res = false;
241
242         batman_ogm_packet = (struct batman_ogm_packet *)forw_packet->skb->data;
243
244         /**
245          * we can aggregate the current packet to this aggregated packet
246          * if:
247          *
248          * - the send time is within our MAX_AGGREGATION_MS time
249          * - the resulting packet wont be bigger than
250          *   MAX_AGGREGATION_BYTES
251          */
252
253         if (time_before(send_time, forw_packet->send_time) &&
254             time_after_eq(send_time + msecs_to_jiffies(MAX_AGGREGATION_MS),
255                                         forw_packet->send_time) &&
256             (aggregated_bytes <= MAX_AGGREGATION_BYTES)) {
257
258                 /**
259                  * check aggregation compatibility
260                  * -> direct link packets are broadcasted on
261                  *    their interface only
262                  * -> aggregate packet if the current packet is
263                  *    a "global" packet as well as the base
264                  *    packet
265                  */
266
267                 primary_if = primary_if_get_selected(bat_priv);
268                 if (!primary_if)
269                         goto out;
270
271                 /* packets without direct link flag and high TTL
272                  * are flooded through the net  */
273                 if ((!directlink) &&
274                     (!(batman_ogm_packet->flags & DIRECTLINK)) &&
275                     (batman_ogm_packet->ttl != 1) &&
276
277                     /* own packets originating non-primary
278                      * interfaces leave only that interface */
279                     ((!forw_packet->own) ||
280                      (forw_packet->if_incoming == primary_if))) {
281                         res = true;
282                         goto out;
283                 }
284
285                 /* if the incoming packet is sent via this one
286                  * interface only - we still can aggregate */
287                 if ((directlink) &&
288                     (new_batman_ogm_packet->ttl == 1) &&
289                     (forw_packet->if_incoming == if_incoming) &&
290
291                     /* packets from direct neighbors or
292                      * own secondary interface packets
293                      * (= secondary interface packets in general) */
294                     (batman_ogm_packet->flags & DIRECTLINK ||
295                      (forw_packet->own &&
296                       forw_packet->if_incoming != primary_if))) {
297                         res = true;
298                         goto out;
299                 }
300         }
301
302 out:
303         if (primary_if)
304                 hardif_free_ref(primary_if);
305         return res;
306 }
307
308 /* create a new aggregated packet and add this packet to it */
309 static void bat_ogm_aggregate_new(const unsigned char *packet_buff,
310                                   int packet_len, unsigned long send_time,
311                                   bool direct_link,
312                                   struct hard_iface *if_incoming,
313                                   int own_packet)
314 {
315         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
316         struct forw_packet *forw_packet_aggr;
317         unsigned char *skb_buff;
318
319         if (!atomic_inc_not_zero(&if_incoming->refcount))
320                 return;
321
322         /* own packet should always be scheduled */
323         if (!own_packet) {
324                 if (!atomic_dec_not_zero(&bat_priv->batman_queue_left)) {
325                         bat_dbg(DBG_BATMAN, bat_priv,
326                                 "batman packet queue full\n");
327                         goto out;
328                 }
329         }
330
331         forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC);
332         if (!forw_packet_aggr) {
333                 if (!own_packet)
334                         atomic_inc(&bat_priv->batman_queue_left);
335                 goto out;
336         }
337
338         if ((atomic_read(&bat_priv->aggregated_ogms)) &&
339             (packet_len < MAX_AGGREGATION_BYTES))
340                 forw_packet_aggr->skb = dev_alloc_skb(MAX_AGGREGATION_BYTES +
341                                                       sizeof(struct ethhdr));
342         else
343                 forw_packet_aggr->skb = dev_alloc_skb(packet_len +
344                                                       sizeof(struct ethhdr));
345
346         if (!forw_packet_aggr->skb) {
347                 if (!own_packet)
348                         atomic_inc(&bat_priv->batman_queue_left);
349                 kfree(forw_packet_aggr);
350                 goto out;
351         }
352         skb_reserve(forw_packet_aggr->skb, sizeof(struct ethhdr));
353
354         INIT_HLIST_NODE(&forw_packet_aggr->list);
355
356         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
357         forw_packet_aggr->packet_len = packet_len;
358         memcpy(skb_buff, packet_buff, packet_len);
359
360         forw_packet_aggr->own = own_packet;
361         forw_packet_aggr->if_incoming = if_incoming;
362         forw_packet_aggr->num_packets = 0;
363         forw_packet_aggr->direct_link_flags = NO_FLAGS;
364         forw_packet_aggr->send_time = send_time;
365
366         /* save packet direct link flag status */
367         if (direct_link)
368                 forw_packet_aggr->direct_link_flags |= 1;
369
370         /* add new packet to packet list */
371         spin_lock_bh(&bat_priv->forw_bat_list_lock);
372         hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
373         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
374
375         /* start timer for this packet */
376         INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
377                           send_outstanding_bat_ogm_packet);
378         queue_delayed_work(bat_event_workqueue,
379                            &forw_packet_aggr->delayed_work,
380                            send_time - jiffies);
381
382         return;
383 out:
384         hardif_free_ref(if_incoming);
385 }
386
387 /* aggregate a new packet into the existing ogm packet */
388 static void bat_ogm_aggregate(struct forw_packet *forw_packet_aggr,
389                               const unsigned char *packet_buff,
390                               int packet_len, bool direct_link)
391 {
392         unsigned char *skb_buff;
393
394         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
395         memcpy(skb_buff, packet_buff, packet_len);
396         forw_packet_aggr->packet_len += packet_len;
397         forw_packet_aggr->num_packets++;
398
399         /* save packet direct link flag status */
400         if (direct_link)
401                 forw_packet_aggr->direct_link_flags |=
402                         (1 << forw_packet_aggr->num_packets);
403 }
404
405 static void bat_ogm_queue_add(struct bat_priv *bat_priv,
406                               unsigned char *packet_buff,
407                               int packet_len, struct hard_iface *if_incoming,
408                               int own_packet, unsigned long send_time)
409 {
410         /**
411          * _aggr -> pointer to the packet we want to aggregate with
412          * _pos -> pointer to the position in the queue
413          */
414         struct forw_packet *forw_packet_aggr = NULL, *forw_packet_pos = NULL;
415         struct hlist_node *tmp_node;
416         struct batman_ogm_packet *batman_ogm_packet;
417         bool direct_link;
418
419         batman_ogm_packet = (struct batman_ogm_packet *)packet_buff;
420         direct_link = batman_ogm_packet->flags & DIRECTLINK ? 1 : 0;
421
422         /* find position for the packet in the forward queue */
423         spin_lock_bh(&bat_priv->forw_bat_list_lock);
424         /* own packets are not to be aggregated */
425         if ((atomic_read(&bat_priv->aggregated_ogms)) && (!own_packet)) {
426                 hlist_for_each_entry(forw_packet_pos, tmp_node,
427                                      &bat_priv->forw_bat_list, list) {
428                         if (bat_ogm_can_aggregate(batman_ogm_packet,
429                                                   bat_priv, packet_len,
430                                                   send_time, direct_link,
431                                                   if_incoming,
432                                                   forw_packet_pos)) {
433                                 forw_packet_aggr = forw_packet_pos;
434                                 break;
435                         }
436                 }
437         }
438
439         /* nothing to aggregate with - either aggregation disabled or no
440          * suitable aggregation packet found */
441         if (!forw_packet_aggr) {
442                 /* the following section can run without the lock */
443                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
444
445                 /**
446                  * if we could not aggregate this packet with one of the others
447                  * we hold it back for a while, so that it might be aggregated
448                  * later on
449                  */
450                 if ((!own_packet) &&
451                     (atomic_read(&bat_priv->aggregated_ogms)))
452                         send_time += msecs_to_jiffies(MAX_AGGREGATION_MS);
453
454                 bat_ogm_aggregate_new(packet_buff, packet_len,
455                                       send_time, direct_link,
456                                       if_incoming, own_packet);
457         } else {
458                 bat_ogm_aggregate(forw_packet_aggr, packet_buff, packet_len,
459                                   direct_link);
460                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
461         }
462 }
463
464 static void bat_ogm_forward(struct orig_node *orig_node,
465                             const struct ethhdr *ethhdr,
466                             struct batman_ogm_packet *batman_ogm_packet,
467                             int directlink, struct hard_iface *if_incoming)
468 {
469         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
470         struct neigh_node *router;
471         uint8_t in_tq, in_ttl, tq_avg = 0;
472         uint8_t tt_num_changes;
473
474         if (batman_ogm_packet->ttl <= 1) {
475                 bat_dbg(DBG_BATMAN, bat_priv, "ttl exceeded\n");
476                 return;
477         }
478
479         router = orig_node_get_router(orig_node);
480
481         in_tq = batman_ogm_packet->tq;
482         in_ttl = batman_ogm_packet->ttl;
483         tt_num_changes = batman_ogm_packet->tt_num_changes;
484
485         batman_ogm_packet->ttl--;
486         memcpy(batman_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
487
488         /* rebroadcast tq of our best ranking neighbor to ensure the rebroadcast
489          * of our best tq value */
490         if (router && router->tq_avg != 0) {
491
492                 /* rebroadcast ogm of best ranking neighbor as is */
493                 if (!compare_eth(router->addr, ethhdr->h_source)) {
494                         batman_ogm_packet->tq = router->tq_avg;
495
496                         if (router->last_ttl)
497                                 batman_ogm_packet->ttl = router->last_ttl - 1;
498                 }
499
500                 tq_avg = router->tq_avg;
501         }
502
503         if (router)
504                 neigh_node_free_ref(router);
505
506         /* apply hop penalty */
507         batman_ogm_packet->tq = hop_penalty(batman_ogm_packet->tq, bat_priv);
508
509         bat_dbg(DBG_BATMAN, bat_priv,
510                 "Forwarding packet: tq_orig: %i, tq_avg: %i, "
511                 "tq_forw: %i, ttl_orig: %i, ttl_forw: %i\n",
512                 in_tq, tq_avg, batman_ogm_packet->tq, in_ttl - 1,
513                 batman_ogm_packet->ttl);
514
515         batman_ogm_packet->seqno = htonl(batman_ogm_packet->seqno);
516         batman_ogm_packet->tt_crc = htons(batman_ogm_packet->tt_crc);
517
518         /* switch of primaries first hop flag when forwarding */
519         batman_ogm_packet->flags &= ~PRIMARIES_FIRST_HOP;
520         if (directlink)
521                 batman_ogm_packet->flags |= DIRECTLINK;
522         else
523                 batman_ogm_packet->flags &= ~DIRECTLINK;
524
525         bat_ogm_queue_add(bat_priv, (unsigned char *)batman_ogm_packet,
526                           BATMAN_OGM_LEN + tt_len(tt_num_changes),
527                           if_incoming, 0, bat_ogm_fwd_send_time());
528 }
529
530 void bat_ogm_schedule(struct hard_iface *hard_iface, int tt_num_changes)
531 {
532         struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
533         struct batman_ogm_packet *batman_ogm_packet;
534         struct hard_iface *primary_if;
535         int vis_server;
536
537         vis_server = atomic_read(&bat_priv->vis_mode);
538         primary_if = primary_if_get_selected(bat_priv);
539
540         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
541
542         /* change sequence number to network order */
543         batman_ogm_packet->seqno =
544                         htonl((uint32_t)atomic_read(&hard_iface->seqno));
545
546         batman_ogm_packet->ttvn = atomic_read(&bat_priv->ttvn);
547         batman_ogm_packet->tt_crc = htons((uint16_t)
548                                                 atomic_read(&bat_priv->tt_crc));
549         if (tt_num_changes >= 0)
550                 batman_ogm_packet->tt_num_changes = tt_num_changes;
551
552         if (vis_server == VIS_TYPE_SERVER_SYNC)
553                 batman_ogm_packet->flags |= VIS_SERVER;
554         else
555                 batman_ogm_packet->flags &= ~VIS_SERVER;
556
557         if ((hard_iface == primary_if) &&
558             (atomic_read(&bat_priv->gw_mode) == GW_MODE_SERVER))
559                 batman_ogm_packet->gw_flags =
560                                 (uint8_t)atomic_read(&bat_priv->gw_bandwidth);
561         else
562                 batman_ogm_packet->gw_flags = NO_FLAGS;
563
564         atomic_inc(&hard_iface->seqno);
565
566         slide_own_bcast_window(hard_iface);
567         bat_ogm_queue_add(bat_priv, hard_iface->packet_buff,
568                           hard_iface->packet_len, hard_iface, 1,
569                           bat_ogm_emit_send_time(bat_priv));
570
571         if (primary_if)
572                 hardif_free_ref(primary_if);
573 }
574
575 static void bat_ogm_orig_update(struct bat_priv *bat_priv,
576                                 struct orig_node *orig_node,
577                                 const struct ethhdr *ethhdr,
578                                 const struct batman_ogm_packet
579                                                         *batman_ogm_packet,
580                                 struct hard_iface *if_incoming,
581                                 const unsigned char *tt_buff, int is_duplicate)
582 {
583         struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
584         struct neigh_node *router = NULL;
585         struct orig_node *orig_node_tmp;
586         struct hlist_node *node;
587         uint8_t bcast_own_sum_orig, bcast_own_sum_neigh;
588
589         bat_dbg(DBG_BATMAN, bat_priv, "update_originator(): "
590                 "Searching and updating originator entry of received packet\n");
591
592         rcu_read_lock();
593         hlist_for_each_entry_rcu(tmp_neigh_node, node,
594                                  &orig_node->neigh_list, list) {
595                 if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) &&
596                     (tmp_neigh_node->if_incoming == if_incoming) &&
597                      atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
598                         if (neigh_node)
599                                 neigh_node_free_ref(neigh_node);
600                         neigh_node = tmp_neigh_node;
601                         continue;
602                 }
603
604                 if (is_duplicate)
605                         continue;
606
607                 spin_lock_bh(&tmp_neigh_node->tq_lock);
608                 ring_buffer_set(tmp_neigh_node->tq_recv,
609                                 &tmp_neigh_node->tq_index, 0);
610                 tmp_neigh_node->tq_avg =
611                         ring_buffer_avg(tmp_neigh_node->tq_recv);
612                 spin_unlock_bh(&tmp_neigh_node->tq_lock);
613         }
614
615         if (!neigh_node) {
616                 struct orig_node *orig_tmp;
617
618                 orig_tmp = get_orig_node(bat_priv, ethhdr->h_source);
619                 if (!orig_tmp)
620                         goto unlock;
621
622                 neigh_node = create_neighbor(orig_node, orig_tmp,
623                                              ethhdr->h_source, if_incoming);
624
625                 orig_node_free_ref(orig_tmp);
626                 if (!neigh_node)
627                         goto unlock;
628         } else
629                 bat_dbg(DBG_BATMAN, bat_priv,
630                         "Updating existing last-hop neighbor of originator\n");
631
632         rcu_read_unlock();
633
634         orig_node->flags = batman_ogm_packet->flags;
635         neigh_node->last_valid = jiffies;
636
637         spin_lock_bh(&neigh_node->tq_lock);
638         ring_buffer_set(neigh_node->tq_recv,
639                         &neigh_node->tq_index,
640                         batman_ogm_packet->tq);
641         neigh_node->tq_avg = ring_buffer_avg(neigh_node->tq_recv);
642         spin_unlock_bh(&neigh_node->tq_lock);
643
644         if (!is_duplicate) {
645                 orig_node->last_ttl = batman_ogm_packet->ttl;
646                 neigh_node->last_ttl = batman_ogm_packet->ttl;
647         }
648
649         bonding_candidate_add(orig_node, neigh_node);
650
651         /* if this neighbor already is our next hop there is nothing
652          * to change */
653         router = orig_node_get_router(orig_node);
654         if (router == neigh_node)
655                 goto update_tt;
656
657         /* if this neighbor does not offer a better TQ we won't consider it */
658         if (router && (router->tq_avg > neigh_node->tq_avg))
659                 goto update_tt;
660
661         /* if the TQ is the same and the link not more symmetric we
662          * won't consider it either */
663         if (router && (neigh_node->tq_avg == router->tq_avg)) {
664                 orig_node_tmp = router->orig_node;
665                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
666                 bcast_own_sum_orig =
667                         orig_node_tmp->bcast_own_sum[if_incoming->if_num];
668                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
669
670                 orig_node_tmp = neigh_node->orig_node;
671                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
672                 bcast_own_sum_neigh =
673                         orig_node_tmp->bcast_own_sum[if_incoming->if_num];
674                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
675
676                 if (bcast_own_sum_orig >= bcast_own_sum_neigh)
677                         goto update_tt;
678         }
679
680         update_route(bat_priv, orig_node, neigh_node);
681
682 update_tt:
683         /* I have to check for transtable changes only if the OGM has been
684          * sent through a primary interface */
685         if (((batman_ogm_packet->orig != ethhdr->h_source) &&
686              (batman_ogm_packet->ttl > 2)) ||
687             (batman_ogm_packet->flags & PRIMARIES_FIRST_HOP))
688                 tt_update_orig(bat_priv, orig_node, tt_buff,
689                                batman_ogm_packet->tt_num_changes,
690                                batman_ogm_packet->ttvn,
691                                batman_ogm_packet->tt_crc);
692
693         if (orig_node->gw_flags != batman_ogm_packet->gw_flags)
694                 gw_node_update(bat_priv, orig_node,
695                                batman_ogm_packet->gw_flags);
696
697         orig_node->gw_flags = batman_ogm_packet->gw_flags;
698
699         /* restart gateway selection if fast or late switching was enabled */
700         if ((orig_node->gw_flags) &&
701             (atomic_read(&bat_priv->gw_mode) == GW_MODE_CLIENT) &&
702             (atomic_read(&bat_priv->gw_sel_class) > 2))
703                 gw_check_election(bat_priv, orig_node);
704
705         goto out;
706
707 unlock:
708         rcu_read_unlock();
709 out:
710         if (neigh_node)
711                 neigh_node_free_ref(neigh_node);
712         if (router)
713                 neigh_node_free_ref(router);
714 }
715
716 static int bat_ogm_calc_tq(struct orig_node *orig_node,
717                            struct orig_node *orig_neigh_node,
718                            struct batman_ogm_packet *batman_ogm_packet,
719                            struct hard_iface *if_incoming)
720 {
721         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
722         struct neigh_node *neigh_node = NULL, *tmp_neigh_node;
723         struct hlist_node *node;
724         uint8_t total_count;
725         uint8_t orig_eq_count, neigh_rq_count, tq_own;
726         int tq_asym_penalty, ret = 0;
727
728         /* find corresponding one hop neighbor */
729         rcu_read_lock();
730         hlist_for_each_entry_rcu(tmp_neigh_node, node,
731                                  &orig_neigh_node->neigh_list, list) {
732
733                 if (!compare_eth(tmp_neigh_node->addr, orig_neigh_node->orig))
734                         continue;
735
736                 if (tmp_neigh_node->if_incoming != if_incoming)
737                         continue;
738
739                 if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
740                         continue;
741
742                 neigh_node = tmp_neigh_node;
743                 break;
744         }
745         rcu_read_unlock();
746
747         if (!neigh_node)
748                 neigh_node = create_neighbor(orig_neigh_node,
749                                              orig_neigh_node,
750                                              orig_neigh_node->orig,
751                                              if_incoming);
752
753         if (!neigh_node)
754                 goto out;
755
756         /* if orig_node is direct neighbor update neigh_node last_valid */
757         if (orig_node == orig_neigh_node)
758                 neigh_node->last_valid = jiffies;
759
760         orig_node->last_valid = jiffies;
761
762         /* find packet count of corresponding one hop neighbor */
763         spin_lock_bh(&orig_node->ogm_cnt_lock);
764         orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num];
765         neigh_rq_count = neigh_node->real_packet_count;
766         spin_unlock_bh(&orig_node->ogm_cnt_lock);
767
768         /* pay attention to not get a value bigger than 100 % */
769         total_count = (orig_eq_count > neigh_rq_count ?
770                        neigh_rq_count : orig_eq_count);
771
772         /* if we have too few packets (too less data) we set tq_own to zero */
773         /* if we receive too few packets it is not considered bidirectional */
774         if ((total_count < TQ_LOCAL_BIDRECT_SEND_MINIMUM) ||
775             (neigh_rq_count < TQ_LOCAL_BIDRECT_RECV_MINIMUM))
776                 tq_own = 0;
777         else
778                 /* neigh_node->real_packet_count is never zero as we
779                  * only purge old information when getting new
780                  * information */
781                 tq_own = (TQ_MAX_VALUE * total_count) / neigh_rq_count;
782
783         /*
784          * 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
785          * affect the nearly-symmetric links only a little, but
786          * punishes asymmetric links more.  This will give a value
787          * between 0 and TQ_MAX_VALUE
788          */
789         tq_asym_penalty = TQ_MAX_VALUE - (TQ_MAX_VALUE *
790                                 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) *
791                                 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) *
792                                 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count)) /
793                                         (TQ_LOCAL_WINDOW_SIZE *
794                                          TQ_LOCAL_WINDOW_SIZE *
795                                          TQ_LOCAL_WINDOW_SIZE);
796
797         batman_ogm_packet->tq = ((batman_ogm_packet->tq * tq_own
798                                                         * tq_asym_penalty) /
799                                                 (TQ_MAX_VALUE * TQ_MAX_VALUE));
800
801         bat_dbg(DBG_BATMAN, bat_priv,
802                 "bidirectional: "
803                 "orig = %-15pM neigh = %-15pM => own_bcast = %2i, "
804                 "real recv = %2i, local tq: %3i, asym_penalty: %3i, "
805                 "total tq: %3i\n",
806                 orig_node->orig, orig_neigh_node->orig, total_count,
807                 neigh_rq_count, tq_own, tq_asym_penalty, batman_ogm_packet->tq);
808
809         /* if link has the minimum required transmission quality
810          * consider it bidirectional */
811         if (batman_ogm_packet->tq >= TQ_TOTAL_BIDRECT_LIMIT)
812                 ret = 1;
813
814 out:
815         if (neigh_node)
816                 neigh_node_free_ref(neigh_node);
817         return ret;
818 }
819
820 /* processes a batman packet for all interfaces, adjusts the sequence number and
821  * finds out whether it is a duplicate.
822  * returns:
823  *   1 the packet is a duplicate
824  *   0 the packet has not yet been received
825  *  -1 the packet is old and has been received while the seqno window
826  *     was protected. Caller should drop it.
827  */
828 static int bat_ogm_update_seqnos(const struct ethhdr *ethhdr,
829                                  const struct batman_ogm_packet
830                                                         *batman_ogm_packet,
831                                  const struct hard_iface *if_incoming)
832 {
833         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
834         struct orig_node *orig_node;
835         struct neigh_node *tmp_neigh_node;
836         struct hlist_node *node;
837         int is_duplicate = 0;
838         int32_t seq_diff;
839         int need_update = 0;
840         int set_mark, ret = -1;
841
842         orig_node = get_orig_node(bat_priv, batman_ogm_packet->orig);
843         if (!orig_node)
844                 return 0;
845
846         spin_lock_bh(&orig_node->ogm_cnt_lock);
847         seq_diff = batman_ogm_packet->seqno - orig_node->last_real_seqno;
848
849         /* signalize caller that the packet is to be dropped. */
850         if (window_protected(bat_priv, seq_diff,
851                              &orig_node->batman_seqno_reset))
852                 goto out;
853
854         rcu_read_lock();
855         hlist_for_each_entry_rcu(tmp_neigh_node, node,
856                                  &orig_node->neigh_list, list) {
857
858                 is_duplicate |= get_bit_status(tmp_neigh_node->real_bits,
859                                                orig_node->last_real_seqno,
860                                                batman_ogm_packet->seqno);
861
862                 if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) &&
863                     (tmp_neigh_node->if_incoming == if_incoming))
864                         set_mark = 1;
865                 else
866                         set_mark = 0;
867
868                 /* if the window moved, set the update flag. */
869                 need_update |= bit_get_packet(bat_priv,
870                                               tmp_neigh_node->real_bits,
871                                               seq_diff, set_mark);
872
873                 tmp_neigh_node->real_packet_count =
874                         bit_packet_count(tmp_neigh_node->real_bits);
875         }
876         rcu_read_unlock();
877
878         if (need_update) {
879                 bat_dbg(DBG_BATMAN, bat_priv,
880                         "updating last_seqno: old %d, new %d\n",
881                         orig_node->last_real_seqno, batman_ogm_packet->seqno);
882                 orig_node->last_real_seqno = batman_ogm_packet->seqno;
883         }
884
885         ret = is_duplicate;
886
887 out:
888         spin_unlock_bh(&orig_node->ogm_cnt_lock);
889         orig_node_free_ref(orig_node);
890         return ret;
891 }
892
893 static void bat_ogm_process(const struct ethhdr *ethhdr,
894                             struct batman_ogm_packet *batman_ogm_packet,
895                             const unsigned char *tt_buff,
896                             struct hard_iface *if_incoming)
897 {
898         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
899         struct hard_iface *hard_iface;
900         struct orig_node *orig_neigh_node, *orig_node;
901         struct neigh_node *router = NULL, *router_router = NULL;
902         struct neigh_node *orig_neigh_router = NULL;
903         int has_directlink_flag;
904         int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
905         int is_broadcast = 0, is_bidirectional, is_single_hop_neigh;
906         int is_duplicate;
907         uint32_t if_incoming_seqno;
908
909         /* Silently drop when the batman packet is actually not a
910          * correct packet.
911          *
912          * This might happen if a packet is padded (e.g. Ethernet has a
913          * minimum frame length of 64 byte) and the aggregation interprets
914          * it as an additional length.
915          *
916          * TODO: A more sane solution would be to have a bit in the
917          * batman_ogm_packet to detect whether the packet is the last
918          * packet in an aggregation.  Here we expect that the padding
919          * is always zero (or not 0x01)
920          */
921         if (batman_ogm_packet->packet_type != BAT_OGM)
922                 return;
923
924         /* could be changed by schedule_own_packet() */
925         if_incoming_seqno = atomic_read(&if_incoming->seqno);
926
927         has_directlink_flag = (batman_ogm_packet->flags & DIRECTLINK ? 1 : 0);
928
929         is_single_hop_neigh = (compare_eth(ethhdr->h_source,
930                                            batman_ogm_packet->orig) ? 1 : 0);
931
932         bat_dbg(DBG_BATMAN, bat_priv,
933                 "Received BATMAN packet via NB: %pM, IF: %s [%pM] "
934                 "(from OG: %pM, via prev OG: %pM, seqno %d, ttvn %u, "
935                 "crc %u, changes %u, td %d, TTL %d, V %d, IDF %d)\n",
936                 ethhdr->h_source, if_incoming->net_dev->name,
937                 if_incoming->net_dev->dev_addr, batman_ogm_packet->orig,
938                 batman_ogm_packet->prev_sender, batman_ogm_packet->seqno,
939                 batman_ogm_packet->ttvn, batman_ogm_packet->tt_crc,
940                 batman_ogm_packet->tt_num_changes, batman_ogm_packet->tq,
941                 batman_ogm_packet->ttl, batman_ogm_packet->version,
942                 has_directlink_flag);
943
944         rcu_read_lock();
945         list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
946                 if (hard_iface->if_status != IF_ACTIVE)
947                         continue;
948
949                 if (hard_iface->soft_iface != if_incoming->soft_iface)
950                         continue;
951
952                 if (compare_eth(ethhdr->h_source,
953                                 hard_iface->net_dev->dev_addr))
954                         is_my_addr = 1;
955
956                 if (compare_eth(batman_ogm_packet->orig,
957                                 hard_iface->net_dev->dev_addr))
958                         is_my_orig = 1;
959
960                 if (compare_eth(batman_ogm_packet->prev_sender,
961                                 hard_iface->net_dev->dev_addr))
962                         is_my_oldorig = 1;
963
964                 if (is_broadcast_ether_addr(ethhdr->h_source))
965                         is_broadcast = 1;
966         }
967         rcu_read_unlock();
968
969         if (batman_ogm_packet->version != COMPAT_VERSION) {
970                 bat_dbg(DBG_BATMAN, bat_priv,
971                         "Drop packet: incompatible batman version (%i)\n",
972                         batman_ogm_packet->version);
973                 return;
974         }
975
976         if (is_my_addr) {
977                 bat_dbg(DBG_BATMAN, bat_priv,
978                         "Drop packet: received my own broadcast (sender: %pM"
979                         ")\n",
980                         ethhdr->h_source);
981                 return;
982         }
983
984         if (is_broadcast) {
985                 bat_dbg(DBG_BATMAN, bat_priv, "Drop packet: "
986                 "ignoring all packets with broadcast source addr (sender: %pM"
987                 ")\n", ethhdr->h_source);
988                 return;
989         }
990
991         if (is_my_orig) {
992                 unsigned long *word;
993                 int offset;
994
995                 orig_neigh_node = get_orig_node(bat_priv, ethhdr->h_source);
996                 if (!orig_neigh_node)
997                         return;
998
999                 /* neighbor has to indicate direct link and it has to
1000                  * come via the corresponding interface */
1001                 /* save packet seqno for bidirectional check */
1002                 if (has_directlink_flag &&
1003                     compare_eth(if_incoming->net_dev->dev_addr,
1004                                 batman_ogm_packet->orig)) {
1005                         offset = if_incoming->if_num * NUM_WORDS;
1006
1007                         spin_lock_bh(&orig_neigh_node->ogm_cnt_lock);
1008                         word = &(orig_neigh_node->bcast_own[offset]);
1009                         bit_mark(word,
1010                                  if_incoming_seqno -
1011                                                 batman_ogm_packet->seqno - 2);
1012                         orig_neigh_node->bcast_own_sum[if_incoming->if_num] =
1013                                 bit_packet_count(word);
1014                         spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);
1015                 }
1016
1017                 bat_dbg(DBG_BATMAN, bat_priv, "Drop packet: "
1018                         "originator packet from myself (via neighbor)\n");
1019                 orig_node_free_ref(orig_neigh_node);
1020                 return;
1021         }
1022
1023         if (is_my_oldorig) {
1024                 bat_dbg(DBG_BATMAN, bat_priv,
1025                         "Drop packet: ignoring all rebroadcast echos (sender: "
1026                         "%pM)\n", ethhdr->h_source);
1027                 return;
1028         }
1029
1030         orig_node = get_orig_node(bat_priv, batman_ogm_packet->orig);
1031         if (!orig_node)
1032                 return;
1033
1034         is_duplicate = bat_ogm_update_seqnos(ethhdr, batman_ogm_packet,
1035                                              if_incoming);
1036
1037         if (is_duplicate == -1) {
1038                 bat_dbg(DBG_BATMAN, bat_priv,
1039                         "Drop packet: packet within seqno protection time "
1040                         "(sender: %pM)\n", ethhdr->h_source);
1041                 goto out;
1042         }
1043
1044         if (batman_ogm_packet->tq == 0) {
1045                 bat_dbg(DBG_BATMAN, bat_priv,
1046                         "Drop packet: originator packet with tq equal 0\n");
1047                 goto out;
1048         }
1049
1050         router = orig_node_get_router(orig_node);
1051         if (router)
1052                 router_router = orig_node_get_router(router->orig_node);
1053
1054         /* avoid temporary routing loops */
1055         if (router && router_router &&
1056             (compare_eth(router->addr, batman_ogm_packet->prev_sender)) &&
1057             !(compare_eth(batman_ogm_packet->orig,
1058                           batman_ogm_packet->prev_sender)) &&
1059             (compare_eth(router->addr, router_router->addr))) {
1060                 bat_dbg(DBG_BATMAN, bat_priv,
1061                         "Drop packet: ignoring all rebroadcast packets that "
1062                         "may make me loop (sender: %pM)\n", ethhdr->h_source);
1063                 goto out;
1064         }
1065
1066         /* if sender is a direct neighbor the sender mac equals
1067          * originator mac */
1068         orig_neigh_node = (is_single_hop_neigh ?
1069                            orig_node :
1070                            get_orig_node(bat_priv, ethhdr->h_source));
1071         if (!orig_neigh_node)
1072                 goto out;
1073
1074         orig_neigh_router = orig_node_get_router(orig_neigh_node);
1075
1076         /* drop packet if sender is not a direct neighbor and if we
1077          * don't route towards it */
1078         if (!is_single_hop_neigh && (!orig_neigh_router)) {
1079                 bat_dbg(DBG_BATMAN, bat_priv,
1080                         "Drop packet: OGM via unknown neighbor!\n");
1081                 goto out_neigh;
1082         }
1083
1084         is_bidirectional = bat_ogm_calc_tq(orig_node, orig_neigh_node,
1085                                            batman_ogm_packet, if_incoming);
1086
1087         bonding_save_primary(orig_node, orig_neigh_node, batman_ogm_packet);
1088
1089         /* update ranking if it is not a duplicate or has the same
1090          * seqno and similar ttl as the non-duplicate */
1091         if (is_bidirectional &&
1092             (!is_duplicate ||
1093              ((orig_node->last_real_seqno == batman_ogm_packet->seqno) &&
1094               (orig_node->last_ttl - 3 <= batman_ogm_packet->ttl))))
1095                 bat_ogm_orig_update(bat_priv, orig_node, ethhdr,
1096                                     batman_ogm_packet, if_incoming,
1097                                     tt_buff, is_duplicate);
1098
1099         /* is single hop (direct) neighbor */
1100         if (is_single_hop_neigh) {
1101
1102                 /* mark direct link on incoming interface */
1103                 bat_ogm_forward(orig_node, ethhdr, batman_ogm_packet,
1104                                 1, if_incoming);
1105
1106                 bat_dbg(DBG_BATMAN, bat_priv, "Forwarding packet: "
1107                         "rebroadcast neighbor packet with direct link flag\n");
1108                 goto out_neigh;
1109         }
1110
1111         /* multihop originator */
1112         if (!is_bidirectional) {
1113                 bat_dbg(DBG_BATMAN, bat_priv,
1114                         "Drop packet: not received via bidirectional link\n");
1115                 goto out_neigh;
1116         }
1117
1118         if (is_duplicate) {
1119                 bat_dbg(DBG_BATMAN, bat_priv,
1120                         "Drop packet: duplicate packet received\n");
1121                 goto out_neigh;
1122         }
1123
1124         bat_dbg(DBG_BATMAN, bat_priv,
1125                 "Forwarding packet: rebroadcast originator packet\n");
1126         bat_ogm_forward(orig_node, ethhdr, batman_ogm_packet, 0, if_incoming);
1127
1128 out_neigh:
1129         if ((orig_neigh_node) && (!is_single_hop_neigh))
1130                 orig_node_free_ref(orig_neigh_node);
1131 out:
1132         if (router)
1133                 neigh_node_free_ref(router);
1134         if (router_router)
1135                 neigh_node_free_ref(router_router);
1136         if (orig_neigh_router)
1137                 neigh_node_free_ref(orig_neigh_router);
1138
1139         orig_node_free_ref(orig_node);
1140 }
1141
1142 void bat_ogm_receive(const struct ethhdr *ethhdr, unsigned char *packet_buff,
1143                      int packet_len, struct hard_iface *if_incoming)
1144 {
1145         struct batman_ogm_packet *batman_ogm_packet;
1146         int buff_pos = 0;
1147         unsigned char *tt_buff;
1148
1149         batman_ogm_packet = (struct batman_ogm_packet *)packet_buff;
1150
1151         /* unpack the aggregated packets and process them one by one */
1152         do {
1153                 /* network to host order for our 32bit seqno and the
1154                    orig_interval */
1155                 batman_ogm_packet->seqno = ntohl(batman_ogm_packet->seqno);
1156                 batman_ogm_packet->tt_crc = ntohs(batman_ogm_packet->tt_crc);
1157
1158                 tt_buff = packet_buff + buff_pos + BATMAN_OGM_LEN;
1159
1160                 bat_ogm_process(ethhdr, batman_ogm_packet,
1161                                 tt_buff, if_incoming);
1162
1163                 buff_pos += BATMAN_OGM_LEN +
1164                                 tt_len(batman_ogm_packet->tt_num_changes);
1165
1166                 batman_ogm_packet = (struct batman_ogm_packet *)
1167                                                 (packet_buff + buff_pos);
1168         } while (bat_ogm_aggr_packet(buff_pos, packet_len,
1169                                      batman_ogm_packet->tt_num_changes));
1170 }