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                                                uint32_t seqno)
  38 {
  39         struct neigh_node *neigh_node;
  40
  41         neigh_node = batadv_neigh_node_new(hard_iface, neigh_addr, seqno);
  42         if (!neigh_node)
  43                 goto out;
  44
  45         INIT_LIST_HEAD(&neigh_node->bonding_list);
  46         spin_lock_init(&neigh_node->tq_lock);
  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 = -1;
  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                 send_skb_packet(skb, hard_iface, broadcast_addr);
 202 }
 203
 204 /* send a batman ogm packet */
 205 static void bat_iv_ogm_emit(struct forw_packet *forw_packet)
 206 {
 207         struct hard_iface *hard_iface;
 208         struct net_device *soft_iface;
 209         struct bat_priv *bat_priv;
 210         struct hard_iface *primary_if = NULL;
 211         struct batman_ogm_packet *batman_ogm_packet;
 212         unsigned char directlink;
 213
 214         batman_ogm_packet = (struct batman_ogm_packet *)
 215                                                 (forw_packet->skb->data);
 216         directlink = (batman_ogm_packet->flags & DIRECTLINK ? 1 : 0);
 217
 218         if (!forw_packet->if_incoming) {
 219                 pr_err("Error - can't forward packet: incoming iface not specified\n");
 220                 goto out;
 221         }
 222
 223         soft_iface = forw_packet->if_incoming->soft_iface;
 224         bat_priv = netdev_priv(soft_iface);
 225
 226         if (forw_packet->if_incoming->if_status != IF_ACTIVE)
 227                 goto out;
 228
 229         primary_if = primary_if_get_selected(bat_priv);
 230         if (!primary_if)
 231                 goto out;
 232
 233         /* multihomed peer assumed */
 234         /* non-primary OGMs are only broadcasted on their interface */
 235         if ((directlink && (batman_ogm_packet->header.ttl == 1)) ||
 236             (forw_packet->own && (forw_packet->if_incoming != primary_if))) {
 237
 238                 /* FIXME: what about aggregated packets ? */
 239                 bat_dbg(DBG_BATMAN, bat_priv,
 240                         "%s packet (originator %pM, seqno %u, TTL %d) on interface %s [%pM]\n",
 241                         (forw_packet->own ? "Sending own" : "Forwarding"),
 242                         batman_ogm_packet->orig,
 243                         ntohl(batman_ogm_packet->seqno),
 244                         batman_ogm_packet->header.ttl,
 245                         forw_packet->if_incoming->net_dev->name,
 246                         forw_packet->if_incoming->net_dev->dev_addr);
 247
 248                 /* skb is only used once and than forw_packet is free'd */
 249                 send_skb_packet(forw_packet->skb, forw_packet->if_incoming,
 250                                 broadcast_addr);
 251                 forw_packet->skb = NULL;
 252
 253                 goto out;
 254         }
 255
 256         /* broadcast on every interface */
 257         rcu_read_lock();
 258         list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
 259                 if (hard_iface->soft_iface != soft_iface)
 260                         continue;
 261
 262                 bat_iv_ogm_send_to_if(forw_packet, hard_iface);
 263         }
 264         rcu_read_unlock();
 265
 266 out:
 267         if (primary_if)
 268                 hardif_free_ref(primary_if);
 269 }
 270
 271 /* return true if new_packet can be aggregated with forw_packet */
 272 static bool bat_iv_ogm_can_aggregate(const struct batman_ogm_packet
 273                                                         *new_batman_ogm_packet,
 274                                      struct bat_priv *bat_priv,
 275                                      int packet_len, unsigned long send_time,
 276                                      bool directlink,
 277                                      const struct hard_iface *if_incoming,
 278                                      const struct forw_packet *forw_packet)
 279 {
 280         struct batman_ogm_packet *batman_ogm_packet;
 281         int aggregated_bytes = forw_packet->packet_len + packet_len;
 282         struct hard_iface *primary_if = NULL;
 283         bool res = false;
 284
 285         batman_ogm_packet = (struct batman_ogm_packet *)forw_packet->skb->data;
 286
 287         /**
 288          * we can aggregate the current packet to this aggregated packet
 289          * if:
 290          *
 291          * - the send time is within our MAX_AGGREGATION_MS time
 292          * - the resulting packet wont be bigger than
 293          *   MAX_AGGREGATION_BYTES
 294          */
 295
 296         if (time_before(send_time, forw_packet->send_time) &&
 297             time_after_eq(send_time + msecs_to_jiffies(MAX_AGGREGATION_MS),
 298                                         forw_packet->send_time) &&
 299             (aggregated_bytes <= MAX_AGGREGATION_BYTES)) {
 300
 301                 /**
 302                  * check aggregation compatibility
 303                  * -> direct link packets are broadcasted on
 304                  *    their interface only
 305                  * -> aggregate packet if the current packet is
 306                  *    a "global" packet as well as the base
 307                  *    packet
 308                  */
 309
 310                 primary_if = primary_if_get_selected(bat_priv);
 311                 if (!primary_if)
 312                         goto out;
 313
 314                 /* packets without direct link flag and high TTL
 315                  * are flooded through the net  */
 316                 if ((!directlink) &&
 317                     (!(batman_ogm_packet->flags & DIRECTLINK)) &&
 318                     (batman_ogm_packet->header.ttl != 1) &&
 319
 320                     /* own packets originating non-primary
 321                      * interfaces leave only that interface */
 322                     ((!forw_packet->own) ||
 323                      (forw_packet->if_incoming == primary_if))) {
 324                         res = true;
 325                         goto out;
 326                 }
 327
 328                 /* if the incoming packet is sent via this one
 329                  * interface only - we still can aggregate */
 330                 if ((directlink) &&
 331                     (new_batman_ogm_packet->header.ttl == 1) &&
 332                     (forw_packet->if_incoming == if_incoming) &&
 333
 334                     /* packets from direct neighbors or
 335                      * own secondary interface packets
 336                      * (= secondary interface packets in general) */
 337                     (batman_ogm_packet->flags & DIRECTLINK ||
 338                      (forw_packet->own &&
 339                       forw_packet->if_incoming != primary_if))) {
 340                         res = true;
 341                         goto out;
 342                 }
 343         }
 344
 345 out:
 346         if (primary_if)
 347                 hardif_free_ref(primary_if);
 348         return res;
 349 }
 350
 351 /* create a new aggregated packet and add this packet to it */
 352 static void bat_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 353                                      int packet_len, unsigned long send_time,
 354                                      bool direct_link,
 355                                      struct hard_iface *if_incoming,
 356                                      int own_packet)
 357 {
 358         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 359         struct forw_packet *forw_packet_aggr;
 360         unsigned char *skb_buff;
 361
 362         if (!atomic_inc_not_zero(&if_incoming->refcount))
 363                 return;
 364
 365         /* own packet should always be scheduled */
 366         if (!own_packet) {
 367                 if (!atomic_dec_not_zero(&bat_priv->batman_queue_left)) {
 368                         bat_dbg(DBG_BATMAN, bat_priv,
 369                                 "batman packet queue full\n");
 370                         goto out;
 371                 }
 372         }
 373
 374         forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC);
 375         if (!forw_packet_aggr) {
 376                 if (!own_packet)
 377                         atomic_inc(&bat_priv->batman_queue_left);
 378                 goto out;
 379         }
 380
 381         if ((atomic_read(&bat_priv->aggregated_ogms)) &&
 382             (packet_len < MAX_AGGREGATION_BYTES))
 383                 forw_packet_aggr->skb = dev_alloc_skb(MAX_AGGREGATION_BYTES +
 384                                                       ETH_HLEN);
 385         else
 386                 forw_packet_aggr->skb = dev_alloc_skb(packet_len + ETH_HLEN);
 387
 388         if (!forw_packet_aggr->skb) {
 389                 if (!own_packet)
 390                         atomic_inc(&bat_priv->batman_queue_left);
 391                 kfree(forw_packet_aggr);
 392                 goto out;
 393         }
 394         skb_reserve(forw_packet_aggr->skb, ETH_HLEN);
 395
 396         INIT_HLIST_NODE(&forw_packet_aggr->list);
 397
 398         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 399         forw_packet_aggr->packet_len = packet_len;
 400         memcpy(skb_buff, packet_buff, packet_len);
 401
 402         forw_packet_aggr->own = own_packet;
 403         forw_packet_aggr->if_incoming = if_incoming;
 404         forw_packet_aggr->num_packets = 0;
 405         forw_packet_aggr->direct_link_flags = NO_FLAGS;
 406         forw_packet_aggr->send_time = send_time;
 407
 408         /* save packet direct link flag status */
 409         if (direct_link)
 410                 forw_packet_aggr->direct_link_flags |= 1;
 411
 412         /* add new packet to packet list */
 413         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 414         hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
 415         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 416
 417         /* start timer for this packet */
 418         INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
 419                           send_outstanding_bat_ogm_packet);
 420         queue_delayed_work(bat_event_workqueue,
 421                            &forw_packet_aggr->delayed_work,
 422                            send_time - jiffies);
 423
 424         return;
 425 out:
 426         hardif_free_ref(if_incoming);
 427 }
 428
 429 /* aggregate a new packet into the existing ogm packet */
 430 static void bat_iv_ogm_aggregate(struct forw_packet *forw_packet_aggr,
 431                                  const unsigned char *packet_buff,
 432                                  int packet_len, bool direct_link)
 433 {
 434         unsigned char *skb_buff;
 435
 436         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 437         memcpy(skb_buff, packet_buff, packet_len);
 438         forw_packet_aggr->packet_len += packet_len;
 439         forw_packet_aggr->num_packets++;
 440
 441         /* save packet direct link flag status */
 442         if (direct_link)
 443                 forw_packet_aggr->direct_link_flags |=
 444                         (1 << forw_packet_aggr->num_packets);
 445 }
 446
 447 static void bat_iv_ogm_queue_add(struct bat_priv *bat_priv,
 448                                  unsigned char *packet_buff,
 449                                  int packet_len, struct hard_iface *if_incoming,
 450                                  int own_packet, unsigned long send_time)
 451 {
 452         /**
 453          * _aggr -> pointer to the packet we want to aggregate with
 454          * _pos -> pointer to the position in the queue
 455          */
 456         struct forw_packet *forw_packet_aggr = NULL, *forw_packet_pos = NULL;
 457         struct hlist_node *tmp_node;
 458         struct batman_ogm_packet *batman_ogm_packet;
 459         bool direct_link;
 460
 461         batman_ogm_packet = (struct batman_ogm_packet *)packet_buff;
 462         direct_link = batman_ogm_packet->flags & DIRECTLINK ? 1 : 0;
 463
 464         /* find position for the packet in the forward queue */
 465         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 466         /* own packets are not to be aggregated */
 467         if ((atomic_read(&bat_priv->aggregated_ogms)) && (!own_packet)) {
 468                 hlist_for_each_entry(forw_packet_pos, tmp_node,
 469                                      &bat_priv->forw_bat_list, list) {
 470                         if (bat_iv_ogm_can_aggregate(batman_ogm_packet,
 471                                                      bat_priv, packet_len,
 472                                                      send_time, direct_link,
 473                                                      if_incoming,
 474                                                      forw_packet_pos)) {
 475                                 forw_packet_aggr = forw_packet_pos;
 476                                 break;
 477                         }
 478                 }
 479         }
 480
 481         /* nothing to aggregate with - either aggregation disabled or no
 482          * suitable aggregation packet found */
 483         if (!forw_packet_aggr) {
 484                 /* the following section can run without the lock */
 485                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 486
 487                 /**
 488                  * if we could not aggregate this packet with one of the others
 489                  * we hold it back for a while, so that it might be aggregated
 490                  * later on
 491                  */
 492                 if ((!own_packet) &&
 493                     (atomic_read(&bat_priv->aggregated_ogms)))
 494                         send_time += msecs_to_jiffies(MAX_AGGREGATION_MS);
 495
 496                 bat_iv_ogm_aggregate_new(packet_buff, packet_len,
 497                                          send_time, direct_link,
 498                                          if_incoming, own_packet);
 499         } else {
 500                 bat_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
 501                                      packet_len, direct_link);
 502                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 503         }
 504 }
 505
 506 static void bat_iv_ogm_forward(struct orig_node *orig_node,
 507                                const struct ethhdr *ethhdr,
 508                                struct batman_ogm_packet *batman_ogm_packet,
 509                                bool is_single_hop_neigh,
 510                                bool is_from_best_next_hop,
 511                                struct hard_iface *if_incoming)
 512 {
 513         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 514         uint8_t tt_num_changes;
 515
 516         if (batman_ogm_packet->header.ttl <= 1) {
 517                 bat_dbg(DBG_BATMAN, bat_priv, "ttl exceeded\n");
 518                 return;
 519         }
 520
 521         if (!is_from_best_next_hop) {
 522                 /* Mark the forwarded packet when it is not coming from our
 523                  * best next hop. We still need to forward the packet for our
 524                  * neighbor link quality detection to work in case the packet
 525                  * originated from a single hop neighbor. Otherwise we can
 526                  * simply drop the ogm.
 527                  */
 528                 if (is_single_hop_neigh)
 529                         batman_ogm_packet->flags |= NOT_BEST_NEXT_HOP;
 530                 else
 531                         return;
 532         }
 533
 534         tt_num_changes = batman_ogm_packet->tt_num_changes;
 535
 536         batman_ogm_packet->header.ttl--;
 537         memcpy(batman_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
 538
 539         /* apply hop penalty */
 540         batman_ogm_packet->tq = hop_penalty(batman_ogm_packet->tq, bat_priv);
 541
 542         bat_dbg(DBG_BATMAN, bat_priv,
 543                 "Forwarding packet: tq: %i, ttl: %i\n",
 544                 batman_ogm_packet->tq, batman_ogm_packet->header.ttl);
 545
 546         batman_ogm_packet->seqno = htonl(batman_ogm_packet->seqno);
 547         batman_ogm_packet->tt_crc = htons(batman_ogm_packet->tt_crc);
 548
 549         /* switch of primaries first hop flag when forwarding */
 550         batman_ogm_packet->flags &= ~PRIMARIES_FIRST_HOP;
 551         if (is_single_hop_neigh)
 552                 batman_ogm_packet->flags |= DIRECTLINK;
 553         else
 554                 batman_ogm_packet->flags &= ~DIRECTLINK;
 555
 556         bat_iv_ogm_queue_add(bat_priv, (unsigned char *)batman_ogm_packet,
 557                              BATMAN_OGM_HLEN + tt_len(tt_num_changes),
 558                              if_incoming, 0, bat_iv_ogm_fwd_send_time());
 559 }
 560
 561 static void bat_iv_ogm_schedule(struct hard_iface *hard_iface,
 562                                 int tt_num_changes)
 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;
 568
 569         vis_server = atomic_read(&bat_priv->vis_mode);
 570         primary_if = primary_if_get_selected(bat_priv);
 571
 572         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
 573
 574         /* change sequence number to network order */
 575         batman_ogm_packet->seqno =
 576                         htonl((uint32_t)atomic_read(&hard_iface->seqno));
 577
 578         batman_ogm_packet->ttvn = atomic_read(&bat_priv->ttvn);
 579         batman_ogm_packet->tt_crc = htons((uint16_t)
 580                                                 atomic_read(&bat_priv->tt_crc));
 581         if (tt_num_changes >= 0)
 582                 batman_ogm_packet->tt_num_changes = tt_num_changes;
 583
 584         if (vis_server == VIS_TYPE_SERVER_SYNC)
 585                 batman_ogm_packet->flags |= VIS_SERVER;
 586         else
 587                 batman_ogm_packet->flags &= ~VIS_SERVER;
 588
 589         if ((hard_iface == primary_if) &&
 590             (atomic_read(&bat_priv->gw_mode) == GW_MODE_SERVER))
 591                 batman_ogm_packet->gw_flags =
 592                                 (uint8_t)atomic_read(&bat_priv->gw_bandwidth);
 593         else
 594                 batman_ogm_packet->gw_flags = NO_FLAGS;
 595
 596         atomic_inc(&hard_iface->seqno);
 597
 598         slide_own_bcast_window(hard_iface);
 599         bat_iv_ogm_queue_add(bat_priv, hard_iface->packet_buff,
 600                              hard_iface->packet_len, hard_iface, 1,
 601                              bat_iv_ogm_emit_send_time(bat_priv));
 602
 603         if (primary_if)
 604                 hardif_free_ref(primary_if);
 605 }
 606
 607 static void bat_iv_ogm_orig_update(struct bat_priv *bat_priv,
 608                                    struct orig_node *orig_node,
 609                                    const struct ethhdr *ethhdr,
 610                                    const struct batman_ogm_packet
 611                                                         *batman_ogm_packet,
 612                                    struct hard_iface *if_incoming,
 613                                    const unsigned char *tt_buff,
 614                                    int is_duplicate)
 615 {
 616         struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 617         struct neigh_node *router = NULL;
 618         struct orig_node *orig_node_tmp;
 619         struct hlist_node *node;
 620         uint8_t bcast_own_sum_orig, bcast_own_sum_neigh;
 621
 622         bat_dbg(DBG_BATMAN, bat_priv,
 623                 "update_originator(): Searching and updating originator entry of received packet\n");
 624
 625         rcu_read_lock();
 626         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 627                                  &orig_node->neigh_list, list) {
 628                 if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) &&
 629                     (tmp_neigh_node->if_incoming == if_incoming) &&
 630                      atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
 631                         if (neigh_node)
 632                                 neigh_node_free_ref(neigh_node);
 633                         neigh_node = tmp_neigh_node;
 634                         continue;
 635                 }
 636
 637                 if (is_duplicate)
 638                         continue;
 639
 640                 spin_lock_bh(&tmp_neigh_node->tq_lock);
 641                 ring_buffer_set(tmp_neigh_node->tq_recv,
 642                                 &tmp_neigh_node->tq_index, 0);
 643                 tmp_neigh_node->tq_avg =
 644                         ring_buffer_avg(tmp_neigh_node->tq_recv);
 645                 spin_unlock_bh(&tmp_neigh_node->tq_lock);
 646         }
 647
 648         if (!neigh_node) {
 649                 struct orig_node *orig_tmp;
 650
 651                 orig_tmp = get_orig_node(bat_priv, ethhdr->h_source);
 652                 if (!orig_tmp)
 653                         goto unlock;
 654
 655                 neigh_node = bat_iv_ogm_neigh_new(if_incoming, ethhdr->h_source,
 656                                                   orig_node, orig_tmp,
 657                                                   batman_ogm_packet->seqno);
 658
 659                 orig_node_free_ref(orig_tmp);
 660                 if (!neigh_node)
 661                         goto unlock;
 662         } else
 663                 bat_dbg(DBG_BATMAN, bat_priv,
 664                         "Updating existing last-hop neighbor of originator\n");
 665
 666         rcu_read_unlock();
 667
 668         orig_node->flags = batman_ogm_packet->flags;
 669         neigh_node->last_seen = jiffies;
 670
 671         spin_lock_bh(&neigh_node->tq_lock);
 672         ring_buffer_set(neigh_node->tq_recv,
 673                         &neigh_node->tq_index,
 674                         batman_ogm_packet->tq);
 675         neigh_node->tq_avg = ring_buffer_avg(neigh_node->tq_recv);
 676         spin_unlock_bh(&neigh_node->tq_lock);
 677
 678         if (!is_duplicate) {
 679                 orig_node->last_ttl = batman_ogm_packet->header.ttl;
 680                 neigh_node->last_ttl = batman_ogm_packet->header.ttl;
 681         }
 682
 683         bonding_candidate_add(orig_node, neigh_node);
 684
 685         /* if this neighbor already is our next hop there is nothing
 686          * to change */
 687         router = orig_node_get_router(orig_node);
 688         if (router == neigh_node)
 689                 goto update_tt;
 690
 691         /* if this neighbor does not offer a better TQ we won't consider it */
 692         if (router && (router->tq_avg > neigh_node->tq_avg))
 693                 goto update_tt;
 694
 695         /* if the TQ is the same and the link not more symmetric we
 696          * won't consider it either */
 697         if (router && (neigh_node->tq_avg == router->tq_avg)) {
 698                 orig_node_tmp = router->orig_node;
 699                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 700                 bcast_own_sum_orig =
 701                         orig_node_tmp->bcast_own_sum[if_incoming->if_num];
 702                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 703
 704                 orig_node_tmp = neigh_node->orig_node;
 705                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 706                 bcast_own_sum_neigh =
 707                         orig_node_tmp->bcast_own_sum[if_incoming->if_num];
 708                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 709
 710                 if (bcast_own_sum_orig >= bcast_own_sum_neigh)
 711                         goto update_tt;
 712         }
 713
 714         update_route(bat_priv, orig_node, neigh_node);
 715
 716 update_tt:
 717         /* I have to check for transtable changes only if the OGM has been
 718          * sent through a primary interface */
 719         if (((batman_ogm_packet->orig != ethhdr->h_source) &&
 720              (batman_ogm_packet->header.ttl > 2)) ||
 721             (batman_ogm_packet->flags & PRIMARIES_FIRST_HOP))
 722                 tt_update_orig(bat_priv, orig_node, tt_buff,
 723                                batman_ogm_packet->tt_num_changes,
 724                                batman_ogm_packet->ttvn,
 725                                batman_ogm_packet->tt_crc);
 726
 727         if (orig_node->gw_flags != batman_ogm_packet->gw_flags)
 728                 gw_node_update(bat_priv, orig_node,
 729                                batman_ogm_packet->gw_flags);
 730
 731         orig_node->gw_flags = batman_ogm_packet->gw_flags;
 732
 733         /* restart gateway selection if fast or late switching was enabled */
 734         if ((orig_node->gw_flags) &&
 735             (atomic_read(&bat_priv->gw_mode) == GW_MODE_CLIENT) &&
 736             (atomic_read(&bat_priv->gw_sel_class) > 2))
 737                 gw_check_election(bat_priv, orig_node);
 738
 739         goto out;
 740
 741 unlock:
 742         rcu_read_unlock();
 743 out:
 744         if (neigh_node)
 745                 neigh_node_free_ref(neigh_node);
 746         if (router)
 747                 neigh_node_free_ref(router);
 748 }
 749
 750 static int bat_iv_ogm_calc_tq(struct orig_node *orig_node,
 751                               struct orig_node *orig_neigh_node,
 752                               struct batman_ogm_packet *batman_ogm_packet,
 753                               struct hard_iface *if_incoming)
 754 {
 755         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 756         struct neigh_node *neigh_node = NULL, *tmp_neigh_node;
 757         struct hlist_node *node;
 758         uint8_t total_count;
 759         uint8_t orig_eq_count, neigh_rq_count, tq_own;
 760         int tq_asym_penalty, ret = 0;
 761
 762         /* find corresponding one hop neighbor */
 763         rcu_read_lock();
 764         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 765                                  &orig_neigh_node->neigh_list, list) {
 766
 767                 if (!compare_eth(tmp_neigh_node->addr, orig_neigh_node->orig))
 768                         continue;
 769
 770                 if (tmp_neigh_node->if_incoming != if_incoming)
 771                         continue;
 772
 773                 if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
 774                         continue;
 775
 776                 neigh_node = tmp_neigh_node;
 777                 break;
 778         }
 779         rcu_read_unlock();
 780
 781         if (!neigh_node)
 782                 neigh_node = bat_iv_ogm_neigh_new(if_incoming,
 783                                                   orig_neigh_node->orig,
 784                                                   orig_neigh_node,
 785                                                   orig_neigh_node,
 786                                                   batman_ogm_packet->seqno);
 787
 788         if (!neigh_node)
 789                 goto out;
 790
 791         /* if orig_node is direct neighbor update neigh_node last_seen */
 792         if (orig_node == orig_neigh_node)
 793                 neigh_node->last_seen = jiffies;
 794
 795         orig_node->last_seen = jiffies;
 796
 797         /* find packet count of corresponding one hop neighbor */
 798         spin_lock_bh(&orig_node->ogm_cnt_lock);
 799         orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num];
 800         neigh_rq_count = neigh_node->real_packet_count;
 801         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 802
 803         /* pay attention to not get a value bigger than 100 % */
 804         total_count = (orig_eq_count > neigh_rq_count ?
 805                        neigh_rq_count : orig_eq_count);
 806
 807         /* if we have too few packets (too less data) we set tq_own to zero */
 808         /* if we receive too few packets it is not considered bidirectional */
 809         if ((total_count < TQ_LOCAL_BIDRECT_SEND_MINIMUM) ||
 810             (neigh_rq_count < TQ_LOCAL_BIDRECT_RECV_MINIMUM))
 811                 tq_own = 0;
 812         else
 813                 /* neigh_node->real_packet_count is never zero as we
 814                  * only purge old information when getting new
 815                  * information */
 816                 tq_own = (TQ_MAX_VALUE * total_count) / neigh_rq_count;
 817
 818         /* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
 819          * affect the nearly-symmetric links only a little, but
 820          * punishes asymmetric links more.  This will give a value
 821          * between 0 and TQ_MAX_VALUE
 822          */
 823         tq_asym_penalty = TQ_MAX_VALUE - (TQ_MAX_VALUE *
 824                                 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) *
 825                                 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) *
 826                                 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count)) /
 827                                         (TQ_LOCAL_WINDOW_SIZE *
 828                                          TQ_LOCAL_WINDOW_SIZE *
 829                                          TQ_LOCAL_WINDOW_SIZE);
 830
 831         batman_ogm_packet->tq = ((batman_ogm_packet->tq * tq_own
 832                                                         * tq_asym_penalty) /
 833                                                 (TQ_MAX_VALUE * TQ_MAX_VALUE));
 834
 835         bat_dbg(DBG_BATMAN, bat_priv,
 836                 "bidirectional: orig = %-15pM neigh = %-15pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, total tq: %3i\n",
 837                 orig_node->orig, orig_neigh_node->orig, total_count,
 838                 neigh_rq_count, tq_own, tq_asym_penalty, batman_ogm_packet->tq);
 839
 840         /* if link has the minimum required transmission quality
 841          * consider it bidirectional */
 842         if (batman_ogm_packet->tq >= TQ_TOTAL_BIDRECT_LIMIT)
 843                 ret = 1;
 844
 845 out:
 846         if (neigh_node)
 847                 neigh_node_free_ref(neigh_node);
 848         return ret;
 849 }
 850
 851 /* processes a batman packet for all interfaces, adjusts the sequence number and
 852  * finds out whether it is a duplicate.
 853  * returns:
 854  *   1 the packet is a duplicate
 855  *   0 the packet has not yet been received
 856  *  -1 the packet is old and has been received while the seqno window
 857  *     was protected. Caller should drop it.
 858  */
 859 static int bat_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
 860                                     const struct batman_ogm_packet
 861                                                         *batman_ogm_packet,
 862                                     const struct hard_iface *if_incoming)
 863 {
 864         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 865         struct orig_node *orig_node;
 866         struct neigh_node *tmp_neigh_node;
 867         struct hlist_node *node;
 868         int is_duplicate = 0;
 869         int32_t seq_diff;
 870         int need_update = 0;
 871         int set_mark, ret = -1;
 872
 873         orig_node = get_orig_node(bat_priv, batman_ogm_packet->orig);
 874         if (!orig_node)
 875                 return 0;
 876
 877         spin_lock_bh(&orig_node->ogm_cnt_lock);
 878         seq_diff = batman_ogm_packet->seqno - orig_node->last_real_seqno;
 879
 880         /* signalize caller that the packet is to be dropped. */
 881         if (!hlist_empty(&orig_node->neigh_list) &&
 882             window_protected(bat_priv, seq_diff,
 883                              &orig_node->batman_seqno_reset))
 884                 goto out;
 885
 886         rcu_read_lock();
 887         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 888                                  &orig_node->neigh_list, list) {
 889
 890                 is_duplicate |= bat_test_bit(tmp_neigh_node->real_bits,
 891                                              orig_node->last_real_seqno,
 892                                              batman_ogm_packet->seqno);
 893
 894                 if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) &&
 895                     (tmp_neigh_node->if_incoming == if_incoming))
 896                         set_mark = 1;
 897                 else
 898                         set_mark = 0;
 899
 900                 /* if the window moved, set the update flag. */
 901                 need_update |= bit_get_packet(bat_priv,
 902                                               tmp_neigh_node->real_bits,
 903                                               seq_diff, set_mark);
 904
 905                 tmp_neigh_node->real_packet_count =
 906                         bitmap_weight(tmp_neigh_node->real_bits,
 907                                       TQ_LOCAL_WINDOW_SIZE);
 908         }
 909         rcu_read_unlock();
 910
 911         if (need_update) {
 912                 bat_dbg(DBG_BATMAN, bat_priv,
 913                         "updating last_seqno: old %u, new %u\n",
 914                         orig_node->last_real_seqno, batman_ogm_packet->seqno);
 915                 orig_node->last_real_seqno = batman_ogm_packet->seqno;
 916         }
 917
 918         ret = is_duplicate;
 919
 920 out:
 921         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 922         orig_node_free_ref(orig_node);
 923         return ret;
 924 }
 925
 926 static void bat_iv_ogm_process(const struct ethhdr *ethhdr,
 927                                struct batman_ogm_packet *batman_ogm_packet,
 928                                const unsigned char *tt_buff,
 929                                struct hard_iface *if_incoming)
 930 {
 931         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 932         struct hard_iface *hard_iface;
 933         struct orig_node *orig_neigh_node, *orig_node;
 934         struct neigh_node *router = NULL, *router_router = NULL;
 935         struct neigh_node *orig_neigh_router = NULL;
 936         int has_directlink_flag;
 937         int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
 938         int is_broadcast = 0, is_bidirectional;
 939         bool is_single_hop_neigh = false;
 940         bool is_from_best_next_hop = false;
 941         int is_duplicate;
 942         uint32_t if_incoming_seqno;
 943
 944         /* Silently drop when the batman packet is actually not a
 945          * correct packet.
 946          *
 947          * This might happen if a packet is padded (e.g. Ethernet has a
 948          * minimum frame length of 64 byte) and the aggregation interprets
 949          * it as an additional length.
 950          *
 951          * TODO: A more sane solution would be to have a bit in the
 952          * batman_ogm_packet to detect whether the packet is the last
 953          * packet in an aggregation.  Here we expect that the padding
 954          * is always zero (or not 0x01)
 955          */
 956         if (batman_ogm_packet->header.packet_type != BAT_IV_OGM)
 957                 return;
 958
 959         /* could be changed by schedule_own_packet() */
 960         if_incoming_seqno = atomic_read(&if_incoming->seqno);
 961
 962         has_directlink_flag = (batman_ogm_packet->flags & DIRECTLINK ? 1 : 0);
 963
 964         if (compare_eth(ethhdr->h_source, batman_ogm_packet->orig))
 965                 is_single_hop_neigh = true;
 966
 967         bat_dbg(DBG_BATMAN, bat_priv,
 968                 "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",
 969                 ethhdr->h_source, if_incoming->net_dev->name,
 970                 if_incoming->net_dev->dev_addr, batman_ogm_packet->orig,
 971                 batman_ogm_packet->prev_sender, batman_ogm_packet->seqno,
 972                 batman_ogm_packet->ttvn, batman_ogm_packet->tt_crc,
 973                 batman_ogm_packet->tt_num_changes, batman_ogm_packet->tq,
 974                 batman_ogm_packet->header.ttl,
 975                 batman_ogm_packet->header.version, has_directlink_flag);
 976
 977         rcu_read_lock();
 978         list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
 979                 if (hard_iface->if_status != IF_ACTIVE)
 980                         continue;
 981
 982                 if (hard_iface->soft_iface != if_incoming->soft_iface)
 983                         continue;
 984
 985                 if (compare_eth(ethhdr->h_source,
 986                                 hard_iface->net_dev->dev_addr))
 987                         is_my_addr = 1;
 988
 989                 if (compare_eth(batman_ogm_packet->orig,
 990                                 hard_iface->net_dev->dev_addr))
 991                         is_my_orig = 1;
 992
 993                 if (compare_eth(batman_ogm_packet->prev_sender,
 994                                 hard_iface->net_dev->dev_addr))
 995                         is_my_oldorig = 1;
 996
 997                 if (is_broadcast_ether_addr(ethhdr->h_source))
 998                         is_broadcast = 1;
 999         }
1000         rcu_read_unlock();
1001
1002         if (batman_ogm_packet->header.version != COMPAT_VERSION) {
1003                 bat_dbg(DBG_BATMAN, bat_priv,
1004                         "Drop packet: incompatible batman version (%i)\n",
1005                         batman_ogm_packet->header.version);
1006                 return;
1007         }
1008
1009         if (is_my_addr) {
1010                 bat_dbg(DBG_BATMAN, bat_priv,
1011                         "Drop packet: received my own broadcast (sender: %pM)\n",
1012                         ethhdr->h_source);
1013                 return;
1014         }
1015
1016         if (is_broadcast) {
1017                 bat_dbg(DBG_BATMAN, bat_priv,
1018                         "Drop packet: ignoring all packets with broadcast source addr (sender: %pM)\n",
1019                         ethhdr->h_source);
1020                 return;
1021         }
1022
1023         if (is_my_orig) {
1024                 unsigned long *word;
1025                 int offset;
1026
1027                 orig_neigh_node = get_orig_node(bat_priv, ethhdr->h_source);
1028                 if (!orig_neigh_node)
1029                         return;
1030
1031                 /* neighbor has to indicate direct link and it has to
1032                  * come via the corresponding interface */
1033                 /* save packet seqno for bidirectional check */
1034                 if (has_directlink_flag &&
1035                     compare_eth(if_incoming->net_dev->dev_addr,
1036                                 batman_ogm_packet->orig)) {
1037                         offset = if_incoming->if_num * NUM_WORDS;
1038
1039                         spin_lock_bh(&orig_neigh_node->ogm_cnt_lock);
1040                         word = &(orig_neigh_node->bcast_own[offset]);
1041                         bat_set_bit(word,
1042                                     if_incoming_seqno -
1043                                                 batman_ogm_packet->seqno - 2);
1044                         orig_neigh_node->bcast_own_sum[if_incoming->if_num] =
1045                                 bitmap_weight(word, TQ_LOCAL_WINDOW_SIZE);
1046                         spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);
1047                 }
1048
1049                 bat_dbg(DBG_BATMAN, bat_priv,
1050                         "Drop packet: originator packet from myself (via neighbor)\n");
1051                 orig_node_free_ref(orig_neigh_node);
1052                 return;
1053         }
1054
1055         if (is_my_oldorig) {
1056                 bat_dbg(DBG_BATMAN, bat_priv,
1057                         "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
1058                         ethhdr->h_source);
1059                 return;
1060         }
1061
1062         if (batman_ogm_packet->flags & NOT_BEST_NEXT_HOP) {
1063                 bat_dbg(DBG_BATMAN, bat_priv,
1064                         "Drop packet: ignoring all packets not forwarded from "
1065                         "the best next hop (sender: %pM)\n", ethhdr->h_source);
1066                 return;
1067         }
1068
1069         orig_node = get_orig_node(bat_priv, batman_ogm_packet->orig);
1070         if (!orig_node)
1071                 return;
1072
1073         is_duplicate = bat_iv_ogm_update_seqnos(ethhdr, batman_ogm_packet,
1074                                                 if_incoming);
1075
1076         if (is_duplicate == -1) {
1077                 bat_dbg(DBG_BATMAN, bat_priv,
1078                         "Drop packet: packet within seqno protection time (sender: %pM)\n",
1079                         ethhdr->h_source);
1080                 goto out;
1081         }
1082
1083         if (batman_ogm_packet->tq == 0) {
1084                 bat_dbg(DBG_BATMAN, bat_priv,
1085                         "Drop packet: originator packet with tq equal 0\n");
1086                 goto out;
1087         }
1088
1089         router = orig_node_get_router(orig_node);
1090         if (router)
1091                 router_router = orig_node_get_router(router->orig_node);
1092
1093         if ((router && router->tq_avg != 0) &&
1094             (compare_eth(router->addr, ethhdr->h_source)))
1095                 is_from_best_next_hop = true;
1096
1097         /* avoid temporary routing loops */
1098         if (router && router_router &&
1099             (compare_eth(router->addr, batman_ogm_packet->prev_sender)) &&
1100             !(compare_eth(batman_ogm_packet->orig,
1101                           batman_ogm_packet->prev_sender)) &&
1102             (compare_eth(router->addr, router_router->addr))) {
1103                 bat_dbg(DBG_BATMAN, bat_priv,
1104                         "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
1105                         ethhdr->h_source);
1106                 goto out;
1107         }
1108
1109         /* if sender is a direct neighbor the sender mac equals
1110          * originator mac */
1111         orig_neigh_node = (is_single_hop_neigh ?
1112                            orig_node :
1113                            get_orig_node(bat_priv, ethhdr->h_source));
1114         if (!orig_neigh_node)
1115                 goto out;
1116
1117         orig_neigh_router = orig_node_get_router(orig_neigh_node);
1118
1119         /* drop packet if sender is not a direct neighbor and if we
1120          * don't route towards it */
1121         if (!is_single_hop_neigh && (!orig_neigh_router)) {
1122                 bat_dbg(DBG_BATMAN, bat_priv,
1123                         "Drop packet: OGM via unknown neighbor!\n");
1124                 goto out_neigh;
1125         }
1126
1127         is_bidirectional = bat_iv_ogm_calc_tq(orig_node, orig_neigh_node,
1128                                               batman_ogm_packet, if_incoming);
1129
1130         bonding_save_primary(orig_node, orig_neigh_node, batman_ogm_packet);
1131
1132         /* update ranking if it is not a duplicate or has the same
1133          * seqno and similar ttl as the non-duplicate */
1134         if (is_bidirectional &&
1135             (!is_duplicate ||
1136              ((orig_node->last_real_seqno == batman_ogm_packet->seqno) &&
1137               (orig_node->last_ttl - 3 <= batman_ogm_packet->header.ttl))))
1138                 bat_iv_ogm_orig_update(bat_priv, orig_node, ethhdr,
1139                                        batman_ogm_packet, if_incoming,
1140                                        tt_buff, is_duplicate);
1141
1142         /* is single hop (direct) neighbor */
1143         if (is_single_hop_neigh) {
1144
1145                 /* mark direct link on incoming interface */
1146                 bat_iv_ogm_forward(orig_node, ethhdr, batman_ogm_packet,
1147                                    is_single_hop_neigh, is_from_best_next_hop,
1148                                    if_incoming);
1149
1150                 bat_dbg(DBG_BATMAN, bat_priv,
1151                         "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
1152                 goto out_neigh;
1153         }
1154
1155         /* multihop originator */
1156         if (!is_bidirectional) {
1157                 bat_dbg(DBG_BATMAN, bat_priv,
1158                         "Drop packet: not received via bidirectional link\n");
1159                 goto out_neigh;
1160         }
1161
1162         if (is_duplicate) {
1163                 bat_dbg(DBG_BATMAN, bat_priv,
1164                         "Drop packet: duplicate packet received\n");
1165                 goto out_neigh;
1166         }
1167
1168         bat_dbg(DBG_BATMAN, bat_priv,
1169                 "Forwarding packet: rebroadcast originator packet\n");
1170         bat_iv_ogm_forward(orig_node, ethhdr, batman_ogm_packet,
1171                            is_single_hop_neigh, is_from_best_next_hop,
1172                            if_incoming);
1173
1174 out_neigh:
1175         if ((orig_neigh_node) && (!is_single_hop_neigh))
1176                 orig_node_free_ref(orig_neigh_node);
1177 out:
1178         if (router)
1179                 neigh_node_free_ref(router);
1180         if (router_router)
1181                 neigh_node_free_ref(router_router);
1182         if (orig_neigh_router)
1183                 neigh_node_free_ref(orig_neigh_router);
1184
1185         orig_node_free_ref(orig_node);
1186 }
1187
1188 static int bat_iv_ogm_receive(struct sk_buff *skb,
1189                               struct hard_iface *if_incoming)
1190 {
1191         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1192         struct batman_ogm_packet *batman_ogm_packet;
1193         struct ethhdr *ethhdr;
1194         int buff_pos = 0, packet_len;
1195         unsigned char *tt_buff, *packet_buff;
1196         bool ret;
1197
1198         ret = check_management_packet(skb, if_incoming, BATMAN_OGM_HLEN);
1199         if (!ret)
1200                 return NET_RX_DROP;
1201
1202         /* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
1203          * that does not have B.A.T.M.A.N. IV enabled ?
1204          */
1205         if (bat_priv->bat_algo_ops->bat_ogm_emit != bat_iv_ogm_emit)
1206                 return NET_RX_DROP;
1207
1208         packet_len = skb_headlen(skb);
1209         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1210         packet_buff = skb->data;
1211         batman_ogm_packet = (struct batman_ogm_packet *)packet_buff;
1212
1213         /* unpack the aggregated packets and process them one by one */
1214         do {
1215                 /* network to host order for our 32bit seqno and the
1216                    orig_interval */
1217                 batman_ogm_packet->seqno = ntohl(batman_ogm_packet->seqno);
1218                 batman_ogm_packet->tt_crc = ntohs(batman_ogm_packet->tt_crc);
1219
1220                 tt_buff = packet_buff + buff_pos + BATMAN_OGM_HLEN;
1221
1222                 bat_iv_ogm_process(ethhdr, batman_ogm_packet,
1223                                    tt_buff, if_incoming);
1224
1225                 buff_pos += BATMAN_OGM_HLEN +
1226                                 tt_len(batman_ogm_packet->tt_num_changes);
1227
1228                 batman_ogm_packet = (struct batman_ogm_packet *)
1229                                                 (packet_buff + buff_pos);
1230         } while (bat_iv_ogm_aggr_packet(buff_pos, packet_len,
1231                                         batman_ogm_packet->tt_num_changes));
1232
1233         kfree_skb(skb);
1234         return NET_RX_SUCCESS;
1235 }
1236
1237 static struct bat_algo_ops batman_iv __read_mostly = {
1238         .name = "BATMAN IV",
1239         .bat_iface_enable = bat_iv_ogm_iface_enable,
1240         .bat_iface_disable = bat_iv_ogm_iface_disable,
1241         .bat_iface_update_mac = bat_iv_ogm_iface_update_mac,
1242         .bat_primary_iface_set = bat_iv_ogm_primary_iface_set,
1243         .bat_ogm_schedule = bat_iv_ogm_schedule,
1244         .bat_ogm_emit = bat_iv_ogm_emit,
1245 };
1246
1247 int __init bat_iv_init(void)
1248 {
1249         int ret;
1250
1251         /* batman originator packet */
1252         ret = recv_handler_register(BAT_IV_OGM, bat_iv_ogm_receive);
1253         if (ret < 0)
1254                 goto out;
1255
1256         ret = bat_algo_register(&batman_iv);
1257         if (ret < 0)
1258                 goto handler_unregister;
1259
1260         goto out;
1261
1262 handler_unregister:
1263         recv_handler_unregister(BAT_IV_OGM);
1264 out:
1265         return ret;
1266 }