net/batman-adv/bat_iv_ogm.c

   1 /*
   2  * Copyright (C) 2007-2012 B.A.T.M.A.N. contributors:
   3  *
   4  * Marek Lindner, Simon Wunderlich
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of version 2 of the GNU General Public
   8  * License as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  18  * 02110-1301, USA
  19  *
  20  */
  21
  22 #include "main.h"
  23 #include "translation-table.h"
  24 #include "ring_buffer.h"
  25 #include "originator.h"
  26 #include "routing.h"
  27 #include "gateway_common.h"
  28 #include "gateway_client.h"
  29 #include "hard-interface.h"
  30 #include "send.h"
  31 #include "bat_algo.h"
  32
  33 static struct neigh_node *bat_iv_ogm_neigh_new(struct hard_iface *hard_iface,
  34                                                const uint8_t *neigh_addr,
  35                                                struct orig_node *orig_node,
  36                                                struct orig_node *orig_neigh,
  37                                                __be32 seqno)
  38 {
  39         struct neigh_node *neigh_node;
  40
  41         neigh_node = batadv_neigh_node_new(hard_iface, neigh_addr,
  42                                            ntohl(seqno));
  43         if (!neigh_node)
  44                 goto out;
  45
  46         INIT_LIST_HEAD(&neigh_node->bonding_list);
  47
  48         neigh_node->orig_node = orig_neigh;
  49         neigh_node->if_incoming = hard_iface;
  50
  51         spin_lock_bh(&orig_node->neigh_list_lock);
  52         hlist_add_head_rcu(&neigh_node->list, &orig_node->neigh_list);
  53         spin_unlock_bh(&orig_node->neigh_list_lock);
  54
  55 out:
  56         return neigh_node;
  57 }
  58
  59 static int bat_iv_ogm_iface_enable(struct hard_iface *hard_iface)
  60 {
  61         struct batman_ogm_packet *batman_ogm_packet;
  62         uint32_t random_seqno;
  63         int res = -ENOMEM;
  64
  65         /* randomize initial seqno to avoid collision */
  66         get_random_bytes(&random_seqno, sizeof(random_seqno));
  67         atomic_set(&hard_iface->seqno, random_seqno);
  68
  69         hard_iface->packet_len = BATMAN_OGM_HLEN;
  70         hard_iface->packet_buff = kmalloc(hard_iface->packet_len, GFP_ATOMIC);
  71
  72         if (!hard_iface->packet_buff)
  73                 goto out;
  74
  75         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
  76         batman_ogm_packet->header.packet_type = BAT_IV_OGM;
  77         batman_ogm_packet->header.version = COMPAT_VERSION;
  78         batman_ogm_packet->header.ttl = 2;
  79         batman_ogm_packet->flags = NO_FLAGS;
  80         batman_ogm_packet->tq = TQ_MAX_VALUE;
  81         batman_ogm_packet->tt_num_changes = 0;
  82         batman_ogm_packet->ttvn = 0;
  83
  84         res = 0;
  85
  86 out:
  87         return res;
  88 }
  89
  90 static void bat_iv_ogm_iface_disable(struct hard_iface *hard_iface)
  91 {
  92         kfree(hard_iface->packet_buff);
  93         hard_iface->packet_buff = NULL;
  94 }
  95
  96 static void bat_iv_ogm_iface_update_mac(struct hard_iface *hard_iface)
  97 {
  98         struct batman_ogm_packet *batman_ogm_packet;
  99
 100         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
 101         memcpy(batman_ogm_packet->orig,
 102                hard_iface->net_dev->dev_addr, ETH_ALEN);
 103         memcpy(batman_ogm_packet->prev_sender,
 104                hard_iface->net_dev->dev_addr, ETH_ALEN);
 105 }
 106
 107 static void bat_iv_ogm_primary_iface_set(struct hard_iface *hard_iface)
 108 {
 109         struct batman_ogm_packet *batman_ogm_packet;
 110
 111         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
 112         batman_ogm_packet->flags = PRIMARIES_FIRST_HOP;
 113         batman_ogm_packet->header.ttl = TTL;
 114 }
 115
 116 /* when do we schedule our own ogm to be sent */
 117 static unsigned long bat_iv_ogm_emit_send_time(const struct bat_priv *bat_priv)
 118 {
 119         return jiffies + msecs_to_jiffies(
 120                    atomic_read(&bat_priv->orig_interval) -
 121                    JITTER + (random32() % 2*JITTER));
 122 }
 123
 124 /* when do we schedule a ogm packet to be sent */
 125 static unsigned long bat_iv_ogm_fwd_send_time(void)
 126 {
 127         return jiffies + msecs_to_jiffies(random32() % (JITTER/2));
 128 }
 129
 130 /* apply hop penalty for a normal link */
 131 static uint8_t hop_penalty(uint8_t tq, const struct bat_priv *bat_priv)
 132 {
 133         int hop_penalty = atomic_read(&bat_priv->hop_penalty);
 134         return (tq * (TQ_MAX_VALUE - hop_penalty)) / (TQ_MAX_VALUE);
 135 }
 136
 137 /* is there another aggregated packet here? */
 138 static int bat_iv_ogm_aggr_packet(int buff_pos, int packet_len,
 139                                   int tt_num_changes)
 140 {
 141         int next_buff_pos = buff_pos + BATMAN_OGM_HLEN + tt_len(tt_num_changes);
 142
 143         return (next_buff_pos <= packet_len) &&
 144                 (next_buff_pos <= MAX_AGGREGATION_BYTES);
 145 }
 146
 147 /* send a batman ogm to a given interface */
 148 static void bat_iv_ogm_send_to_if(struct forw_packet *forw_packet,
 149                                   struct hard_iface *hard_iface)
 150 {
 151         struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 152         char *fwd_str;
 153         uint8_t packet_num;
 154         int16_t buff_pos;
 155         struct batman_ogm_packet *batman_ogm_packet;
 156         struct sk_buff *skb;
 157
 158         if (hard_iface->if_status != IF_ACTIVE)
 159                 return;
 160
 161         packet_num = 0;
 162         buff_pos = 0;
 163         batman_ogm_packet = (struct batman_ogm_packet *)forw_packet->skb->data;
 164
 165         /* adjust all flags and log packets */
 166         while (bat_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
 167                                       batman_ogm_packet->tt_num_changes)) {
 168
 169                 /* we might have aggregated direct link packets with an
 170                  * ordinary base packet */
 171                 if ((forw_packet->direct_link_flags & (1 << packet_num)) &&
 172                     (forw_packet->if_incoming == hard_iface))
 173                         batman_ogm_packet->flags |= DIRECTLINK;
 174                 else
 175                         batman_ogm_packet->flags &= ~DIRECTLINK;
 176
 177                 fwd_str = (packet_num > 0 ? "Forwarding" : (forw_packet->own ?
 178                                                             "Sending own" :
 179                                                             "Forwarding"));
 180                 bat_dbg(DBG_BATMAN, bat_priv,
 181                         "%s %spacket (originator %pM, seqno %u, TQ %d, TTL %d, IDF %s, ttvn %d) on interface %s [%pM]\n",
 182                         fwd_str, (packet_num > 0 ? "aggregated " : ""),
 183                         batman_ogm_packet->orig,
 184                         ntohl(batman_ogm_packet->seqno),
 185                         batman_ogm_packet->tq, batman_ogm_packet->header.ttl,
 186                         (batman_ogm_packet->flags & DIRECTLINK ?
 187                          "on" : "off"),
 188                         batman_ogm_packet->ttvn, hard_iface->net_dev->name,
 189                         hard_iface->net_dev->dev_addr);
 190
 191                 buff_pos += BATMAN_OGM_HLEN +
 192                                 tt_len(batman_ogm_packet->tt_num_changes);
 193                 packet_num++;
 194                 batman_ogm_packet = (struct batman_ogm_packet *)
 195                                         (forw_packet->skb->data + buff_pos);
 196         }
 197
 198         /* create clone because function is called more than once */
 199         skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
 200         if (skb) {
 201                 batadv_inc_counter(bat_priv, BAT_CNT_MGMT_TX);
 202                 batadv_add_counter(bat_priv, BAT_CNT_MGMT_TX_BYTES,
 203                                    skb->len + ETH_HLEN);
 204                 send_skb_packet(skb, hard_iface, broadcast_addr);
 205         }
 206 }
 207
 208 /* send a batman ogm packet */
 209 static void bat_iv_ogm_emit(struct forw_packet *forw_packet)
 210 {
 211         struct hard_iface *hard_iface;
 212         struct net_device *soft_iface;
 213         struct bat_priv *bat_priv;
 214         struct hard_iface *primary_if = NULL;
 215         struct batman_ogm_packet *batman_ogm_packet;
 216         unsigned char directlink;
 217
 218         batman_ogm_packet = (struct batman_ogm_packet *)
 219                                                 (forw_packet->skb->data);
 220         directlink = (batman_ogm_packet->flags & DIRECTLINK ? 1 : 0);
 221
 222         if (!forw_packet->if_incoming) {
 223                 pr_err("Error - can't forward packet: incoming iface not specified\n");
 224                 goto out;
 225         }
 226
 227         soft_iface = forw_packet->if_incoming->soft_iface;
 228         bat_priv = netdev_priv(soft_iface);
 229
 230         if (forw_packet->if_incoming->if_status != IF_ACTIVE)
 231                 goto out;
 232
 233         primary_if = primary_if_get_selected(bat_priv);
 234         if (!primary_if)
 235                 goto out;
 236
 237         /* multihomed peer assumed */
 238         /* non-primary OGMs are only broadcasted on their interface */
 239         if ((directlink && (batman_ogm_packet->header.ttl == 1)) ||
 240             (forw_packet->own && (forw_packet->if_incoming != primary_if))) {
 241
 242                 /* FIXME: what about aggregated packets ? */
 243                 bat_dbg(DBG_BATMAN, bat_priv,
 244                         "%s packet (originator %pM, seqno %u, TTL %d) on interface %s [%pM]\n",
 245                         (forw_packet->own ? "Sending own" : "Forwarding"),
 246                         batman_ogm_packet->orig,
 247                         ntohl(batman_ogm_packet->seqno),
 248                         batman_ogm_packet->header.ttl,
 249                         forw_packet->if_incoming->net_dev->name,
 250                         forw_packet->if_incoming->net_dev->dev_addr);
 251
 252                 /* skb is only used once and than forw_packet is free'd */
 253                 send_skb_packet(forw_packet->skb, forw_packet->if_incoming,
 254                                 broadcast_addr);
 255                 forw_packet->skb = NULL;
 256
 257                 goto out;
 258         }
 259
 260         /* broadcast on every interface */
 261         rcu_read_lock();
 262         list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
 263                 if (hard_iface->soft_iface != soft_iface)
 264                         continue;
 265
 266                 bat_iv_ogm_send_to_if(forw_packet, hard_iface);
 267         }
 268         rcu_read_unlock();
 269
 270 out:
 271         if (primary_if)
 272                 hardif_free_ref(primary_if);
 273 }
 274
 275 /* return true if new_packet can be aggregated with forw_packet */
 276 static bool bat_iv_ogm_can_aggregate(const struct batman_ogm_packet
 277                                                         *new_batman_ogm_packet,
 278                                      struct bat_priv *bat_priv,
 279                                      int packet_len, unsigned long send_time,
 280                                      bool directlink,
 281                                      const struct hard_iface *if_incoming,
 282                                      const struct forw_packet *forw_packet)
 283 {
 284         struct batman_ogm_packet *batman_ogm_packet;
 285         int aggregated_bytes = forw_packet->packet_len + packet_len;
 286         struct hard_iface *primary_if = NULL;
 287         bool res = false;
 288
 289         batman_ogm_packet = (struct batman_ogm_packet *)forw_packet->skb->data;
 290
 291         /**
 292          * we can aggregate the current packet to this aggregated packet
 293          * if:
 294          *
 295          * - the send time is within our MAX_AGGREGATION_MS time
 296          * - the resulting packet wont be bigger than
 297          *   MAX_AGGREGATION_BYTES
 298          */
 299
 300         if (time_before(send_time, forw_packet->send_time) &&
 301             time_after_eq(send_time + msecs_to_jiffies(MAX_AGGREGATION_MS),
 302                                         forw_packet->send_time) &&
 303             (aggregated_bytes <= MAX_AGGREGATION_BYTES)) {
 304
 305                 /**
 306                  * check aggregation compatibility
 307                  * -> direct link packets are broadcasted on
 308                  *    their interface only
 309                  * -> aggregate packet if the current packet is
 310                  *    a "global" packet as well as the base
 311                  *    packet
 312                  */
 313
 314                 primary_if = primary_if_get_selected(bat_priv);
 315                 if (!primary_if)
 316                         goto out;
 317
 318                 /* packets without direct link flag and high TTL
 319                  * are flooded through the net  */
 320                 if ((!directlink) &&
 321                     (!(batman_ogm_packet->flags & DIRECTLINK)) &&
 322                     (batman_ogm_packet->header.ttl != 1) &&
 323
 324                     /* own packets originating non-primary
 325                      * interfaces leave only that interface */
 326                     ((!forw_packet->own) ||
 327                      (forw_packet->if_incoming == primary_if))) {
 328                         res = true;
 329                         goto out;
 330                 }
 331
 332                 /* if the incoming packet is sent via this one
 333                  * interface only - we still can aggregate */
 334                 if ((directlink) &&
 335                     (new_batman_ogm_packet->header.ttl == 1) &&
 336                     (forw_packet->if_incoming == if_incoming) &&
 337
 338                     /* packets from direct neighbors or
 339                      * own secondary interface packets
 340                      * (= secondary interface packets in general) */
 341                     (batman_ogm_packet->flags & DIRECTLINK ||
 342                      (forw_packet->own &&
 343                       forw_packet->if_incoming != primary_if))) {
 344                         res = true;
 345                         goto out;
 346                 }
 347         }
 348
 349 out:
 350         if (primary_if)
 351                 hardif_free_ref(primary_if);
 352         return res;
 353 }
 354
 355 /* create a new aggregated packet and add this packet to it */
 356 static void bat_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 357                                      int packet_len, unsigned long send_time,
 358                                      bool direct_link,
 359                                      struct hard_iface *if_incoming,
 360                                      int own_packet)
 361 {
 362         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 363         struct forw_packet *forw_packet_aggr;
 364         unsigned char *skb_buff;
 365
 366         if (!atomic_inc_not_zero(&if_incoming->refcount))
 367                 return;
 368
 369         /* own packet should always be scheduled */
 370         if (!own_packet) {
 371                 if (!atomic_dec_not_zero(&bat_priv->batman_queue_left)) {
 372                         bat_dbg(DBG_BATMAN, bat_priv,
 373                                 "batman packet queue full\n");
 374                         goto out;
 375                 }
 376         }
 377
 378         forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC);
 379         if (!forw_packet_aggr) {
 380                 if (!own_packet)
 381                         atomic_inc(&bat_priv->batman_queue_left);
 382                 goto out;
 383         }
 384
 385         if ((atomic_read(&bat_priv->aggregated_ogms)) &&
 386             (packet_len < MAX_AGGREGATION_BYTES))
 387                 forw_packet_aggr->skb = dev_alloc_skb(MAX_AGGREGATION_BYTES +
 388                                                       ETH_HLEN);
 389         else
 390                 forw_packet_aggr->skb = dev_alloc_skb(packet_len + ETH_HLEN);
 391
 392         if (!forw_packet_aggr->skb) {
 393                 if (!own_packet)
 394                         atomic_inc(&bat_priv->batman_queue_left);
 395                 kfree(forw_packet_aggr);
 396                 goto out;
 397         }
 398         skb_reserve(forw_packet_aggr->skb, ETH_HLEN);
 399
 400         INIT_HLIST_NODE(&forw_packet_aggr->list);
 401
 402         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 403         forw_packet_aggr->packet_len = packet_len;
 404         memcpy(skb_buff, packet_buff, packet_len);
 405
 406         forw_packet_aggr->own = own_packet;
 407         forw_packet_aggr->if_incoming = if_incoming;
 408         forw_packet_aggr->num_packets = 0;
 409         forw_packet_aggr->direct_link_flags = NO_FLAGS;
 410         forw_packet_aggr->send_time = send_time;
 411
 412         /* save packet direct link flag status */
 413         if (direct_link)
 414                 forw_packet_aggr->direct_link_flags |= 1;
 415
 416         /* add new packet to packet list */
 417         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 418         hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
 419         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 420
 421         /* start timer for this packet */
 422         INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
 423                           send_outstanding_bat_ogm_packet);
 424         queue_delayed_work(bat_event_workqueue,
 425                            &forw_packet_aggr->delayed_work,
 426                            send_time - jiffies);
 427
 428         return;
 429 out:
 430         hardif_free_ref(if_incoming);
 431 }
 432
 433 /* aggregate a new packet into the existing ogm packet */
 434 static void bat_iv_ogm_aggregate(struct forw_packet *forw_packet_aggr,
 435                                  const unsigned char *packet_buff,
 436                                  int packet_len, bool direct_link)
 437 {
 438         unsigned char *skb_buff;
 439
 440         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 441         memcpy(skb_buff, packet_buff, packet_len);
 442         forw_packet_aggr->packet_len += packet_len;
 443         forw_packet_aggr->num_packets++;
 444
 445         /* save packet direct link flag status */
 446         if (direct_link)
 447                 forw_packet_aggr->direct_link_flags |=
 448                         (1 << forw_packet_aggr->num_packets);
 449 }
 450
 451 static void bat_iv_ogm_queue_add(struct bat_priv *bat_priv,
 452                                  unsigned char *packet_buff,
 453                                  int packet_len, struct hard_iface *if_incoming,
 454                                  int own_packet, unsigned long send_time)
 455 {
 456         /**
 457          * _aggr -> pointer to the packet we want to aggregate with
 458          * _pos -> pointer to the position in the queue
 459          */
 460         struct forw_packet *forw_packet_aggr = NULL, *forw_packet_pos = NULL;
 461         struct hlist_node *tmp_node;
 462         struct batman_ogm_packet *batman_ogm_packet;
 463         bool direct_link;
 464
 465         batman_ogm_packet = (struct batman_ogm_packet *)packet_buff;
 466         direct_link = batman_ogm_packet->flags & DIRECTLINK ? 1 : 0;
 467
 468         /* find position for the packet in the forward queue */
 469         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 470         /* own packets are not to be aggregated */
 471         if ((atomic_read(&bat_priv->aggregated_ogms)) && (!own_packet)) {
 472                 hlist_for_each_entry(forw_packet_pos, tmp_node,
 473                                      &bat_priv->forw_bat_list, list) {
 474                         if (bat_iv_ogm_can_aggregate(batman_ogm_packet,
 475                                                      bat_priv, packet_len,
 476                                                      send_time, direct_link,
 477                                                      if_incoming,
 478                                                      forw_packet_pos)) {
 479                                 forw_packet_aggr = forw_packet_pos;
 480                                 break;
 481                         }
 482                 }
 483         }
 484
 485         /* nothing to aggregate with - either aggregation disabled or no
 486          * suitable aggregation packet found */
 487         if (!forw_packet_aggr) {
 488                 /* the following section can run without the lock */
 489                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 490
 491                 /**
 492                  * if we could not aggregate this packet with one of the others
 493                  * we hold it back for a while, so that it might be aggregated
 494                  * later on
 495                  */
 496                 if ((!own_packet) &&
 497                     (atomic_read(&bat_priv->aggregated_ogms)))
 498                         send_time += msecs_to_jiffies(MAX_AGGREGATION_MS);
 499
 500                 bat_iv_ogm_aggregate_new(packet_buff, packet_len,
 501                                          send_time, direct_link,
 502                                          if_incoming, own_packet);
 503         } else {
 504                 bat_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
 505                                      packet_len, direct_link);
 506                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 507         }
 508 }
 509
 510 static void bat_iv_ogm_forward(struct orig_node *orig_node,
 511                                const struct ethhdr *ethhdr,
 512                                struct batman_ogm_packet *batman_ogm_packet,
 513                                bool is_single_hop_neigh,
 514                                bool is_from_best_next_hop,
 515                                struct hard_iface *if_incoming)
 516 {
 517         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 518         uint8_t tt_num_changes;
 519
 520         if (batman_ogm_packet->header.ttl <= 1) {
 521                 bat_dbg(DBG_BATMAN, bat_priv, "ttl exceeded\n");
 522                 return;
 523         }
 524
 525         if (!is_from_best_next_hop) {
 526                 /* Mark the forwarded packet when it is not coming from our
 527                  * best next hop. We still need to forward the packet for our
 528                  * neighbor link quality detection to work in case the packet
 529                  * originated from a single hop neighbor. Otherwise we can
 530                  * simply drop the ogm.
 531                  */
 532                 if (is_single_hop_neigh)
 533                         batman_ogm_packet->flags |= NOT_BEST_NEXT_HOP;
 534                 else
 535                         return;
 536         }
 537
 538         tt_num_changes = batman_ogm_packet->tt_num_changes;
 539
 540         batman_ogm_packet->header.ttl--;
 541         memcpy(batman_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
 542
 543         /* apply hop penalty */
 544         batman_ogm_packet->tq = hop_penalty(batman_ogm_packet->tq, bat_priv);
 545
 546         bat_dbg(DBG_BATMAN, bat_priv,
 547                 "Forwarding packet: tq: %i, ttl: %i\n",
 548                 batman_ogm_packet->tq, batman_ogm_packet->header.ttl);
 549
 550         /* switch of primaries first hop flag when forwarding */
 551         batman_ogm_packet->flags &= ~PRIMARIES_FIRST_HOP;
 552         if (is_single_hop_neigh)
 553                 batman_ogm_packet->flags |= DIRECTLINK;
 554         else
 555                 batman_ogm_packet->flags &= ~DIRECTLINK;
 556
 557         bat_iv_ogm_queue_add(bat_priv, (unsigned char *)batman_ogm_packet,
 558                              BATMAN_OGM_HLEN + tt_len(tt_num_changes),
 559                              if_incoming, 0, bat_iv_ogm_fwd_send_time());
 560 }
 561
 562 static void bat_iv_ogm_schedule(struct hard_iface *hard_iface)
 563 {
 564         struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 565         struct batman_ogm_packet *batman_ogm_packet;
 566         struct hard_iface *primary_if;
 567         int vis_server, tt_num_changes = 0;
 568
 569         vis_server = atomic_read(&bat_priv->vis_mode);
 570         primary_if = primary_if_get_selected(bat_priv);
 571
 572         if (hard_iface == primary_if)
 573                 tt_num_changes = batadv_tt_append_diff(bat_priv,
 574                                                        &hard_iface->packet_buff,
 575                                                        &hard_iface->packet_len,
 576                                                        BATMAN_OGM_HLEN);
 577
 578         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
 579
 580         /* change sequence number to network order */
 581         batman_ogm_packet->seqno =
 582                         htonl((uint32_t)atomic_read(&hard_iface->seqno));
 583         atomic_inc(&hard_iface->seqno);
 584
 585         batman_ogm_packet->ttvn = atomic_read(&bat_priv->ttvn);
 586         batman_ogm_packet->tt_crc = htons(bat_priv->tt_crc);
 587         if (tt_num_changes >= 0)
 588                 batman_ogm_packet->tt_num_changes = tt_num_changes;
 589
 590         if (vis_server == VIS_TYPE_SERVER_SYNC)
 591                 batman_ogm_packet->flags |= VIS_SERVER;
 592         else
 593                 batman_ogm_packet->flags &= ~VIS_SERVER;
 594
 595         if ((hard_iface == primary_if) &&
 596             (atomic_read(&bat_priv->gw_mode) == GW_MODE_SERVER))
 597                 batman_ogm_packet->gw_flags =
 598                                 (uint8_t)atomic_read(&bat_priv->gw_bandwidth);
 599         else
 600                 batman_ogm_packet->gw_flags = NO_FLAGS;
 601
 602         slide_own_bcast_window(hard_iface);
 603         bat_iv_ogm_queue_add(bat_priv, hard_iface->packet_buff,
 604                              hard_iface->packet_len, hard_iface, 1,
 605                              bat_iv_ogm_emit_send_time(bat_priv));
 606
 607         if (primary_if)
 608                 hardif_free_ref(primary_if);
 609 }
 610
 611 static void bat_iv_ogm_orig_update(struct bat_priv *bat_priv,
 612                                    struct orig_node *orig_node,
 613                                    const struct ethhdr *ethhdr,
 614                                    const struct batman_ogm_packet
 615                                                         *batman_ogm_packet,
 616                                    struct hard_iface *if_incoming,
 617                                    const unsigned char *tt_buff,
 618                                    int is_duplicate)
 619 {
 620         struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 621         struct neigh_node *router = NULL;
 622         struct orig_node *orig_node_tmp;
 623         struct hlist_node *node;
 624         uint8_t bcast_own_sum_orig, bcast_own_sum_neigh;
 625
 626         bat_dbg(DBG_BATMAN, bat_priv,
 627                 "update_originator(): Searching and updating originator entry of received packet\n");
 628
 629         rcu_read_lock();
 630         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 631                                  &orig_node->neigh_list, list) {
 632                 if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) &&
 633                     (tmp_neigh_node->if_incoming == if_incoming) &&
 634                      atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
 635                         if (neigh_node)
 636                                 neigh_node_free_ref(neigh_node);
 637                         neigh_node = tmp_neigh_node;
 638                         continue;
 639                 }
 640
 641                 if (is_duplicate)
 642                         continue;
 643
 644                 spin_lock_bh(&tmp_neigh_node->lq_update_lock);
 645                 ring_buffer_set(tmp_neigh_node->tq_recv,
 646                                 &tmp_neigh_node->tq_index, 0);
 647                 tmp_neigh_node->tq_avg =
 648                         ring_buffer_avg(tmp_neigh_node->tq_recv);
 649                 spin_unlock_bh(&tmp_neigh_node->lq_update_lock);
 650         }
 651
 652         if (!neigh_node) {
 653                 struct orig_node *orig_tmp;
 654
 655                 orig_tmp = get_orig_node(bat_priv, ethhdr->h_source);
 656                 if (!orig_tmp)
 657                         goto unlock;
 658
 659                 neigh_node = bat_iv_ogm_neigh_new(if_incoming, ethhdr->h_source,
 660                                                   orig_node, orig_tmp,
 661                                                   batman_ogm_packet->seqno);
 662
 663                 orig_node_free_ref(orig_tmp);
 664                 if (!neigh_node)
 665                         goto unlock;
 666         } else
 667                 bat_dbg(DBG_BATMAN, bat_priv,
 668                         "Updating existing last-hop neighbor of originator\n");
 669
 670         rcu_read_unlock();
 671
 672         orig_node->flags = batman_ogm_packet->flags;
 673         neigh_node->last_seen = jiffies;
 674
 675         spin_lock_bh(&neigh_node->lq_update_lock);
 676         ring_buffer_set(neigh_node->tq_recv,
 677                         &neigh_node->tq_index,
 678                         batman_ogm_packet->tq);
 679         neigh_node->tq_avg = ring_buffer_avg(neigh_node->tq_recv);
 680         spin_unlock_bh(&neigh_node->lq_update_lock);
 681
 682         if (!is_duplicate) {
 683                 orig_node->last_ttl = batman_ogm_packet->header.ttl;
 684                 neigh_node->last_ttl = batman_ogm_packet->header.ttl;
 685         }
 686
 687         bonding_candidate_add(orig_node, neigh_node);
 688
 689         /* if this neighbor already is our next hop there is nothing
 690          * to change */
 691         router = orig_node_get_router(orig_node);
 692         if (router == neigh_node)
 693                 goto update_tt;
 694
 695         /* if this neighbor does not offer a better TQ we won't consider it */
 696         if (router && (router->tq_avg > neigh_node->tq_avg))
 697                 goto update_tt;
 698
 699         /* if the TQ is the same and the link not more symmetric we
 700          * won't consider it either */
 701         if (router && (neigh_node->tq_avg == router->tq_avg)) {
 702                 orig_node_tmp = router->orig_node;
 703                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 704                 bcast_own_sum_orig =
 705                         orig_node_tmp->bcast_own_sum[if_incoming->if_num];
 706                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 707
 708                 orig_node_tmp = neigh_node->orig_node;
 709                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 710                 bcast_own_sum_neigh =
 711                         orig_node_tmp->bcast_own_sum[if_incoming->if_num];
 712                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 713
 714                 if (bcast_own_sum_orig >= bcast_own_sum_neigh)
 715                         goto update_tt;
 716         }
 717
 718         update_route(bat_priv, orig_node, neigh_node);
 719
 720 update_tt:
 721         /* I have to check for transtable changes only if the OGM has been
 722          * sent through a primary interface */
 723         if (((batman_ogm_packet->orig != ethhdr->h_source) &&
 724              (batman_ogm_packet->header.ttl > 2)) ||
 725             (batman_ogm_packet->flags & PRIMARIES_FIRST_HOP))
 726                 tt_update_orig(bat_priv, orig_node, tt_buff,
 727                                batman_ogm_packet->tt_num_changes,
 728                                batman_ogm_packet->ttvn,
 729                                ntohs(batman_ogm_packet->tt_crc));
 730
 731         if (orig_node->gw_flags != batman_ogm_packet->gw_flags)
 732                 batadv_gw_node_update(bat_priv, orig_node,
 733                                       batman_ogm_packet->gw_flags);
 734
 735         orig_node->gw_flags = batman_ogm_packet->gw_flags;
 736
 737         /* restart gateway selection if fast or late switching was enabled */
 738         if ((orig_node->gw_flags) &&
 739             (atomic_read(&bat_priv->gw_mode) == GW_MODE_CLIENT) &&
 740             (atomic_read(&bat_priv->gw_sel_class) > 2))
 741                 batadv_gw_check_election(bat_priv, orig_node);
 742
 743         goto out;
 744
 745 unlock:
 746         rcu_read_unlock();
 747 out:
 748         if (neigh_node)
 749                 neigh_node_free_ref(neigh_node);
 750         if (router)
 751                 neigh_node_free_ref(router);
 752 }
 753
 754 static int bat_iv_ogm_calc_tq(struct orig_node *orig_node,
 755                               struct orig_node *orig_neigh_node,
 756                               struct batman_ogm_packet *batman_ogm_packet,
 757                               struct hard_iface *if_incoming)
 758 {
 759         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 760         struct neigh_node *neigh_node = NULL, *tmp_neigh_node;
 761         struct hlist_node *node;
 762         uint8_t total_count;
 763         uint8_t orig_eq_count, neigh_rq_count, tq_own;
 764         int tq_asym_penalty, ret = 0;
 765
 766         /* find corresponding one hop neighbor */
 767         rcu_read_lock();
 768         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 769                                  &orig_neigh_node->neigh_list, list) {
 770
 771                 if (!compare_eth(tmp_neigh_node->addr, orig_neigh_node->orig))
 772                         continue;
 773
 774                 if (tmp_neigh_node->if_incoming != if_incoming)
 775                         continue;
 776
 777                 if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
 778                         continue;
 779
 780                 neigh_node = tmp_neigh_node;
 781                 break;
 782         }
 783         rcu_read_unlock();
 784
 785         if (!neigh_node)
 786                 neigh_node = bat_iv_ogm_neigh_new(if_incoming,
 787                                                   orig_neigh_node->orig,
 788                                                   orig_neigh_node,
 789                                                   orig_neigh_node,
 790                                                   batman_ogm_packet->seqno);
 791
 792         if (!neigh_node)
 793                 goto out;
 794
 795         /* if orig_node is direct neighbor update neigh_node last_seen */
 796         if (orig_node == orig_neigh_node)
 797                 neigh_node->last_seen = jiffies;
 798
 799         orig_node->last_seen = jiffies;
 800
 801         /* find packet count of corresponding one hop neighbor */
 802         spin_lock_bh(&orig_node->ogm_cnt_lock);
 803         orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num];
 804         neigh_rq_count = neigh_node->real_packet_count;
 805         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 806
 807         /* pay attention to not get a value bigger than 100 % */
 808         total_count = (orig_eq_count > neigh_rq_count ?
 809                        neigh_rq_count : orig_eq_count);
 810
 811         /* if we have too few packets (too less data) we set tq_own to zero */
 812         /* if we receive too few packets it is not considered bidirectional */
 813         if ((total_count < TQ_LOCAL_BIDRECT_SEND_MINIMUM) ||
 814             (neigh_rq_count < TQ_LOCAL_BIDRECT_RECV_MINIMUM))
 815                 tq_own = 0;
 816         else
 817                 /* neigh_node->real_packet_count is never zero as we
 818                  * only purge old information when getting new
 819                  * information */
 820                 tq_own = (TQ_MAX_VALUE * total_count) / neigh_rq_count;
 821
 822         /* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
 823          * affect the nearly-symmetric links only a little, but
 824          * punishes asymmetric links more.  This will give a value
 825          * between 0 and TQ_MAX_VALUE
 826          */
 827         tq_asym_penalty = TQ_MAX_VALUE - (TQ_MAX_VALUE *
 828                                 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) *
 829                                 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) *
 830                                 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count)) /
 831                                         (TQ_LOCAL_WINDOW_SIZE *
 832                                          TQ_LOCAL_WINDOW_SIZE *
 833                                          TQ_LOCAL_WINDOW_SIZE);
 834
 835         batman_ogm_packet->tq = ((batman_ogm_packet->tq * tq_own
 836                                                         * tq_asym_penalty) /
 837                                                 (TQ_MAX_VALUE * TQ_MAX_VALUE));
 838
 839         bat_dbg(DBG_BATMAN, bat_priv,
 840                 "bidirectional: orig = %-15pM neigh = %-15pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, total tq: %3i\n",
 841                 orig_node->orig, orig_neigh_node->orig, total_count,
 842                 neigh_rq_count, tq_own, tq_asym_penalty, batman_ogm_packet->tq);
 843
 844         /* if link has the minimum required transmission quality
 845          * consider it bidirectional */
 846         if (batman_ogm_packet->tq >= TQ_TOTAL_BIDRECT_LIMIT)
 847                 ret = 1;
 848
 849 out:
 850         if (neigh_node)
 851                 neigh_node_free_ref(neigh_node);
 852         return ret;
 853 }
 854
 855 /* processes a batman packet for all interfaces, adjusts the sequence number and
 856  * finds out whether it is a duplicate.
 857  * returns:
 858  *   1 the packet is a duplicate
 859  *   0 the packet has not yet been received
 860  *  -1 the packet is old and has been received while the seqno window
 861  *     was protected. Caller should drop it.
 862  */
 863 static int bat_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
 864                                     const struct batman_ogm_packet
 865                                                         *batman_ogm_packet,
 866                                     const struct hard_iface *if_incoming)
 867 {
 868         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 869         struct orig_node *orig_node;
 870         struct neigh_node *tmp_neigh_node;
 871         struct hlist_node *node;
 872         int is_duplicate = 0;
 873         int32_t seq_diff;
 874         int need_update = 0;
 875         int set_mark, ret = -1;
 876         uint32_t seqno = ntohl(batman_ogm_packet->seqno);
 877
 878         orig_node = get_orig_node(bat_priv, batman_ogm_packet->orig);
 879         if (!orig_node)
 880                 return 0;
 881
 882         spin_lock_bh(&orig_node->ogm_cnt_lock);
 883         seq_diff = seqno - orig_node->last_real_seqno;
 884
 885         /* signalize caller that the packet is to be dropped. */
 886         if (!hlist_empty(&orig_node->neigh_list) &&
 887             window_protected(bat_priv, seq_diff,
 888                              &orig_node->batman_seqno_reset))
 889                 goto out;
 890
 891         rcu_read_lock();
 892         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 893                                  &orig_node->neigh_list, list) {
 894
 895                 is_duplicate |= bat_test_bit(tmp_neigh_node->real_bits,
 896                                              orig_node->last_real_seqno,
 897                                              seqno);
 898
 899                 if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) &&
 900                     (tmp_neigh_node->if_incoming == if_incoming))
 901                         set_mark = 1;
 902                 else
 903                         set_mark = 0;
 904
 905                 /* if the window moved, set the update flag. */
 906                 need_update |= batadv_bit_get_packet(bat_priv,
 907                                                      tmp_neigh_node->real_bits,
 908                                                      seq_diff, set_mark);
 909
 910                 tmp_neigh_node->real_packet_count =
 911                         bitmap_weight(tmp_neigh_node->real_bits,
 912                                       TQ_LOCAL_WINDOW_SIZE);
 913         }
 914         rcu_read_unlock();
 915
 916         if (need_update) {
 917                 bat_dbg(DBG_BATMAN, bat_priv,
 918                         "updating last_seqno: old %u, new %u\n",
 919                         orig_node->last_real_seqno, seqno);
 920                 orig_node->last_real_seqno = seqno;
 921         }
 922
 923         ret = is_duplicate;
 924
 925 out:
 926         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 927         orig_node_free_ref(orig_node);
 928         return ret;
 929 }
 930
 931 static void bat_iv_ogm_process(const struct ethhdr *ethhdr,
 932                                struct batman_ogm_packet *batman_ogm_packet,
 933                                const unsigned char *tt_buff,
 934                                struct hard_iface *if_incoming)
 935 {
 936         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 937         struct hard_iface *hard_iface;
 938         struct orig_node *orig_neigh_node, *orig_node;
 939         struct neigh_node *router = NULL, *router_router = NULL;
 940         struct neigh_node *orig_neigh_router = NULL;
 941         int has_directlink_flag;
 942         int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
 943         int is_broadcast = 0, is_bidirectional;
 944         bool is_single_hop_neigh = false;
 945         bool is_from_best_next_hop = false;
 946         int is_duplicate;
 947         uint32_t if_incoming_seqno;
 948
 949         /* Silently drop when the batman packet is actually not a
 950          * correct packet.
 951          *
 952          * This might happen if a packet is padded (e.g. Ethernet has a
 953          * minimum frame length of 64 byte) and the aggregation interprets
 954          * it as an additional length.
 955          *
 956          * TODO: A more sane solution would be to have a bit in the
 957          * batman_ogm_packet to detect whether the packet is the last
 958          * packet in an aggregation.  Here we expect that the padding
 959          * is always zero (or not 0x01)
 960          */
 961         if (batman_ogm_packet->header.packet_type != BAT_IV_OGM)
 962                 return;
 963
 964         /* could be changed by schedule_own_packet() */
 965         if_incoming_seqno = atomic_read(&if_incoming->seqno);
 966
 967         has_directlink_flag = (batman_ogm_packet->flags & DIRECTLINK ? 1 : 0);
 968
 969         if (compare_eth(ethhdr->h_source, batman_ogm_packet->orig))
 970                 is_single_hop_neigh = true;
 971
 972         bat_dbg(DBG_BATMAN, bat_priv,
 973                 "Received BATMAN packet via NB: %pM, IF: %s [%pM] (from OG: %pM, via prev OG: %pM, seqno %u, ttvn %u, crc %u, changes %u, td %d, TTL %d, V %d, IDF %d)\n",
 974                 ethhdr->h_source, if_incoming->net_dev->name,
 975                 if_incoming->net_dev->dev_addr, batman_ogm_packet->orig,
 976                 batman_ogm_packet->prev_sender, ntohl(batman_ogm_packet->seqno),
 977                 batman_ogm_packet->ttvn, ntohs(batman_ogm_packet->tt_crc),
 978                 batman_ogm_packet->tt_num_changes, batman_ogm_packet->tq,
 979                 batman_ogm_packet->header.ttl,
 980                 batman_ogm_packet->header.version, has_directlink_flag);
 981
 982         rcu_read_lock();
 983         list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
 984                 if (hard_iface->if_status != IF_ACTIVE)
 985                         continue;
 986
 987                 if (hard_iface->soft_iface != if_incoming->soft_iface)
 988                         continue;
 989
 990                 if (compare_eth(ethhdr->h_source,
 991                                 hard_iface->net_dev->dev_addr))
 992                         is_my_addr = 1;
 993
 994                 if (compare_eth(batman_ogm_packet->orig,
 995                                 hard_iface->net_dev->dev_addr))
 996                         is_my_orig = 1;
 997
 998                 if (compare_eth(batman_ogm_packet->prev_sender,
 999                                 hard_iface->net_dev->dev_addr))
1000                         is_my_oldorig = 1;
1001
1002                 if (is_broadcast_ether_addr(ethhdr->h_source))
1003                         is_broadcast = 1;
1004         }
1005         rcu_read_unlock();
1006
1007         if (batman_ogm_packet->header.version != COMPAT_VERSION) {
1008                 bat_dbg(DBG_BATMAN, bat_priv,
1009                         "Drop packet: incompatible batman version (%i)\n",
1010                         batman_ogm_packet->header.version);
1011                 return;
1012         }
1013
1014         if (is_my_addr) {
1015                 bat_dbg(DBG_BATMAN, bat_priv,
1016                         "Drop packet: received my own broadcast (sender: %pM)\n",
1017                         ethhdr->h_source);
1018                 return;
1019         }
1020
1021         if (is_broadcast) {
1022                 bat_dbg(DBG_BATMAN, bat_priv,
1023                         "Drop packet: ignoring all packets with broadcast source addr (sender: %pM)\n",
1024                         ethhdr->h_source);
1025                 return;
1026         }
1027
1028         if (is_my_orig) {
1029                 unsigned long *word;
1030                 int offset;
1031
1032                 orig_neigh_node = get_orig_node(bat_priv, ethhdr->h_source);
1033                 if (!orig_neigh_node)
1034                         return;
1035
1036                 /* neighbor has to indicate direct link and it has to
1037                  * come via the corresponding interface */
1038                 /* save packet seqno for bidirectional check */
1039                 if (has_directlink_flag &&
1040                     compare_eth(if_incoming->net_dev->dev_addr,
1041                                 batman_ogm_packet->orig)) {
1042                         offset = if_incoming->if_num * NUM_WORDS;
1043
1044                         spin_lock_bh(&orig_neigh_node->ogm_cnt_lock);
1045                         word = &(orig_neigh_node->bcast_own[offset]);
1046                         bat_set_bit(word,
1047                                     if_incoming_seqno -
1048                                         ntohl(batman_ogm_packet->seqno) - 2);
1049                         orig_neigh_node->bcast_own_sum[if_incoming->if_num] =
1050                                 bitmap_weight(word, TQ_LOCAL_WINDOW_SIZE);
1051                         spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);
1052                 }
1053
1054                 bat_dbg(DBG_BATMAN, bat_priv,
1055                         "Drop packet: originator packet from myself (via neighbor)\n");
1056                 orig_node_free_ref(orig_neigh_node);
1057                 return;
1058         }
1059
1060         if (is_my_oldorig) {
1061                 bat_dbg(DBG_BATMAN, bat_priv,
1062                         "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
1063                         ethhdr->h_source);
1064                 return;
1065         }
1066
1067         if (batman_ogm_packet->flags & NOT_BEST_NEXT_HOP) {
1068                 bat_dbg(DBG_BATMAN, bat_priv,
1069                         "Drop packet: ignoring all packets not forwarded from the best next hop (sender: %pM)\n",
1070                         ethhdr->h_source);
1071                 return;
1072         }
1073
1074         orig_node = get_orig_node(bat_priv, batman_ogm_packet->orig);
1075         if (!orig_node)
1076                 return;
1077
1078         is_duplicate = bat_iv_ogm_update_seqnos(ethhdr, batman_ogm_packet,
1079                                                 if_incoming);
1080
1081         if (is_duplicate == -1) {
1082                 bat_dbg(DBG_BATMAN, bat_priv,
1083                         "Drop packet: packet within seqno protection time (sender: %pM)\n",
1084                         ethhdr->h_source);
1085                 goto out;
1086         }
1087
1088         if (batman_ogm_packet->tq == 0) {
1089                 bat_dbg(DBG_BATMAN, bat_priv,
1090                         "Drop packet: originator packet with tq equal 0\n");
1091                 goto out;
1092         }
1093
1094         router = orig_node_get_router(orig_node);
1095         if (router)
1096                 router_router = orig_node_get_router(router->orig_node);
1097
1098         if ((router && router->tq_avg != 0) &&
1099             (compare_eth(router->addr, ethhdr->h_source)))
1100                 is_from_best_next_hop = true;
1101
1102         /* avoid temporary routing loops */
1103         if (router && router_router &&
1104             (compare_eth(router->addr, batman_ogm_packet->prev_sender)) &&
1105             !(compare_eth(batman_ogm_packet->orig,
1106                           batman_ogm_packet->prev_sender)) &&
1107             (compare_eth(router->addr, router_router->addr))) {
1108                 bat_dbg(DBG_BATMAN, bat_priv,
1109                         "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
1110                         ethhdr->h_source);
1111                 goto out;
1112         }
1113
1114         /* if sender is a direct neighbor the sender mac equals
1115          * originator mac */
1116         orig_neigh_node = (is_single_hop_neigh ?
1117                            orig_node :
1118                            get_orig_node(bat_priv, ethhdr->h_source));
1119         if (!orig_neigh_node)
1120                 goto out;
1121
1122         orig_neigh_router = orig_node_get_router(orig_neigh_node);
1123
1124         /* drop packet if sender is not a direct neighbor and if we
1125          * don't route towards it */
1126         if (!is_single_hop_neigh && (!orig_neigh_router)) {
1127                 bat_dbg(DBG_BATMAN, bat_priv,
1128                         "Drop packet: OGM via unknown neighbor!\n");
1129                 goto out_neigh;
1130         }
1131
1132         is_bidirectional = bat_iv_ogm_calc_tq(orig_node, orig_neigh_node,
1133                                               batman_ogm_packet, if_incoming);
1134
1135         bonding_save_primary(orig_node, orig_neigh_node, batman_ogm_packet);
1136
1137         /* update ranking if it is not a duplicate or has the same
1138          * seqno and similar ttl as the non-duplicate */
1139         if (is_bidirectional &&
1140             (!is_duplicate ||
1141              ((orig_node->last_real_seqno == ntohl(batman_ogm_packet->seqno)) &&
1142               (orig_node->last_ttl - 3 <= batman_ogm_packet->header.ttl))))
1143                 bat_iv_ogm_orig_update(bat_priv, orig_node, ethhdr,
1144                                        batman_ogm_packet, if_incoming,
1145                                        tt_buff, is_duplicate);
1146
1147         /* is single hop (direct) neighbor */
1148         if (is_single_hop_neigh) {
1149
1150                 /* mark direct link on incoming interface */
1151                 bat_iv_ogm_forward(orig_node, ethhdr, batman_ogm_packet,
1152                                    is_single_hop_neigh, is_from_best_next_hop,
1153                                    if_incoming);
1154
1155                 bat_dbg(DBG_BATMAN, bat_priv,
1156                         "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
1157                 goto out_neigh;
1158         }
1159
1160         /* multihop originator */
1161         if (!is_bidirectional) {
1162                 bat_dbg(DBG_BATMAN, bat_priv,
1163                         "Drop packet: not received via bidirectional link\n");
1164                 goto out_neigh;
1165         }
1166
1167         if (is_duplicate) {
1168                 bat_dbg(DBG_BATMAN, bat_priv,
1169                         "Drop packet: duplicate packet received\n");
1170                 goto out_neigh;
1171         }
1172
1173         bat_dbg(DBG_BATMAN, bat_priv,
1174                 "Forwarding packet: rebroadcast originator packet\n");
1175         bat_iv_ogm_forward(orig_node, ethhdr, batman_ogm_packet,
1176                            is_single_hop_neigh, is_from_best_next_hop,
1177                            if_incoming);
1178
1179 out_neigh:
1180         if ((orig_neigh_node) && (!is_single_hop_neigh))
1181                 orig_node_free_ref(orig_neigh_node);
1182 out:
1183         if (router)
1184                 neigh_node_free_ref(router);
1185         if (router_router)
1186                 neigh_node_free_ref(router_router);
1187         if (orig_neigh_router)
1188                 neigh_node_free_ref(orig_neigh_router);
1189
1190         orig_node_free_ref(orig_node);
1191 }
1192
1193 static int bat_iv_ogm_receive(struct sk_buff *skb,
1194                               struct hard_iface *if_incoming)
1195 {
1196         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1197         struct batman_ogm_packet *batman_ogm_packet;
1198         struct ethhdr *ethhdr;
1199         int buff_pos = 0, packet_len;
1200         unsigned char *tt_buff, *packet_buff;
1201         bool ret;
1202
1203         ret = check_management_packet(skb, if_incoming, BATMAN_OGM_HLEN);
1204         if (!ret)
1205                 return NET_RX_DROP;
1206
1207         /* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
1208          * that does not have B.A.T.M.A.N. IV enabled ?
1209          */
1210         if (bat_priv->bat_algo_ops->bat_ogm_emit != bat_iv_ogm_emit)
1211                 return NET_RX_DROP;
1212
1213         batadv_inc_counter(bat_priv, BAT_CNT_MGMT_RX);
1214         batadv_add_counter(bat_priv, BAT_CNT_MGMT_RX_BYTES,
1215                            skb->len + ETH_HLEN);
1216
1217         packet_len = skb_headlen(skb);
1218         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1219         packet_buff = skb->data;
1220         batman_ogm_packet = (struct batman_ogm_packet *)packet_buff;
1221
1222         /* unpack the aggregated packets and process them one by one */
1223         do {
1224                 tt_buff = packet_buff + buff_pos + BATMAN_OGM_HLEN;
1225
1226                 bat_iv_ogm_process(ethhdr, batman_ogm_packet,
1227                                    tt_buff, if_incoming);
1228
1229                 buff_pos += BATMAN_OGM_HLEN +
1230                                 tt_len(batman_ogm_packet->tt_num_changes);
1231
1232                 batman_ogm_packet = (struct batman_ogm_packet *)
1233                                                 (packet_buff + buff_pos);
1234         } while (bat_iv_ogm_aggr_packet(buff_pos, packet_len,
1235                                         batman_ogm_packet->tt_num_changes));
1236
1237         kfree_skb(skb);
1238         return NET_RX_SUCCESS;
1239 }
1240
1241 static struct bat_algo_ops batman_iv __read_mostly = {
1242         .name = "BATMAN_IV",
1243         .bat_iface_enable = bat_iv_ogm_iface_enable,
1244         .bat_iface_disable = bat_iv_ogm_iface_disable,
1245         .bat_iface_update_mac = bat_iv_ogm_iface_update_mac,
1246         .bat_primary_iface_set = bat_iv_ogm_primary_iface_set,
1247         .bat_ogm_schedule = bat_iv_ogm_schedule,
1248         .bat_ogm_emit = bat_iv_ogm_emit,
1249 };
1250
1251 int __init batadv_iv_init(void)
1252 {
1253         int ret;
1254
1255         /* batman originator packet */
1256         ret = recv_handler_register(BAT_IV_OGM, bat_iv_ogm_receive);
1257         if (ret < 0)
1258                 goto out;
1259
1260         ret = bat_algo_register(&batman_iv);
1261         if (ret < 0)
1262                 goto handler_unregister;
1263
1264         goto out;
1265
1266 handler_unregister:
1267         recv_handler_unregister(BAT_IV_OGM);
1268 out:
1269         return ret;
1270 }