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 int bat_iv_ogm_iface_enable(struct hard_iface *hard_iface)
  34 {
  35         struct batman_ogm_packet *batman_ogm_packet;
  36         uint32_t random_seqno;
  37         int res = -1;
  38
  39         /* randomize initial seqno to avoid collision */
  40         get_random_bytes(&random_seqno, sizeof(random_seqno));
  41         atomic_set(&hard_iface->seqno, random_seqno);
  42
  43         hard_iface->packet_len = BATMAN_OGM_HLEN;
  44         hard_iface->packet_buff = kmalloc(hard_iface->packet_len, GFP_ATOMIC);
  45
  46         if (!hard_iface->packet_buff)
  47                 goto out;
  48
  49         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
  50         batman_ogm_packet->header.packet_type = BAT_IV_OGM;
  51         batman_ogm_packet->header.version = COMPAT_VERSION;
  52         batman_ogm_packet->header.ttl = 2;
  53         batman_ogm_packet->flags = NO_FLAGS;
  54         batman_ogm_packet->tq = TQ_MAX_VALUE;
  55         batman_ogm_packet->tt_num_changes = 0;
  56         batman_ogm_packet->ttvn = 0;
  57
  58         res = 0;
  59
  60 out:
  61         return res;
  62 }
  63
  64 static void bat_iv_ogm_iface_disable(struct hard_iface *hard_iface)
  65 {
  66         kfree(hard_iface->packet_buff);
  67         hard_iface->packet_buff = NULL;
  68 }
  69
  70 static void bat_iv_ogm_primary_iface_set(struct hard_iface *hard_iface)
  71 {
  72         struct batman_ogm_packet *batman_ogm_packet;
  73
  74         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
  75         batman_ogm_packet->flags = PRIMARIES_FIRST_HOP;
  76         batman_ogm_packet->header.ttl = TTL;
  77 }
  78
  79 static void bat_iv_ogm_update_mac(struct hard_iface *hard_iface)
  80 {
  81         struct batman_ogm_packet *batman_ogm_packet;
  82
  83         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
  84         memcpy(batman_ogm_packet->orig,
  85                hard_iface->net_dev->dev_addr, ETH_ALEN);
  86         memcpy(batman_ogm_packet->prev_sender,
  87                hard_iface->net_dev->dev_addr, ETH_ALEN);
  88 }
  89
  90 /* when do we schedule our own ogm to be sent */
  91 static unsigned long bat_iv_ogm_emit_send_time(const struct bat_priv *bat_priv)
  92 {
  93         return jiffies + msecs_to_jiffies(
  94                    atomic_read(&bat_priv->orig_interval) -
  95                    JITTER + (random32() % 2*JITTER));
  96 }
  97
  98 /* when do we schedule a ogm packet to be sent */
  99 static unsigned long bat_iv_ogm_fwd_send_time(void)
 100 {
 101         return jiffies + msecs_to_jiffies(random32() % (JITTER/2));
 102 }
 103
 104 /* apply hop penalty for a normal link */
 105 static uint8_t hop_penalty(uint8_t tq, const struct bat_priv *bat_priv)
 106 {
 107         int hop_penalty = atomic_read(&bat_priv->hop_penalty);
 108         return (tq * (TQ_MAX_VALUE - hop_penalty)) / (TQ_MAX_VALUE);
 109 }
 110
 111 /* is there another aggregated packet here? */
 112 static int bat_iv_ogm_aggr_packet(int buff_pos, int packet_len,
 113                                   int tt_num_changes)
 114 {
 115         int next_buff_pos = buff_pos + BATMAN_OGM_HLEN + tt_len(tt_num_changes);
 116
 117         return (next_buff_pos <= packet_len) &&
 118                 (next_buff_pos <= MAX_AGGREGATION_BYTES);
 119 }
 120
 121 /* send a batman ogm to a given interface */
 122 static void bat_iv_ogm_send_to_if(struct forw_packet *forw_packet,
 123                                   struct hard_iface *hard_iface)
 124 {
 125         struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 126         char *fwd_str;
 127         uint8_t packet_num;
 128         int16_t buff_pos;
 129         struct batman_ogm_packet *batman_ogm_packet;
 130         struct sk_buff *skb;
 131
 132         if (hard_iface->if_status != IF_ACTIVE)
 133                 return;
 134
 135         packet_num = 0;
 136         buff_pos = 0;
 137         batman_ogm_packet = (struct batman_ogm_packet *)forw_packet->skb->data;
 138
 139         /* adjust all flags and log packets */
 140         while (bat_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
 141                                       batman_ogm_packet->tt_num_changes)) {
 142
 143                 /* we might have aggregated direct link packets with an
 144                  * ordinary base packet */
 145                 if ((forw_packet->direct_link_flags & (1 << packet_num)) &&
 146                     (forw_packet->if_incoming == hard_iface))
 147                         batman_ogm_packet->flags |= DIRECTLINK;
 148                 else
 149                         batman_ogm_packet->flags &= ~DIRECTLINK;
 150
 151                 fwd_str = (packet_num > 0 ? "Forwarding" : (forw_packet->own ?
 152                                                             "Sending own" :
 153                                                             "Forwarding"));
 154                 bat_dbg(DBG_BATMAN, bat_priv,
 155                         "%s %spacket (originator %pM, seqno %u, TQ %d, TTL %d, IDF %s, ttvn %d) on interface %s [%pM]\n",
 156                         fwd_str, (packet_num > 0 ? "aggregated " : ""),
 157                         batman_ogm_packet->orig,
 158                         ntohl(batman_ogm_packet->seqno),
 159                         batman_ogm_packet->tq, batman_ogm_packet->header.ttl,
 160                         (batman_ogm_packet->flags & DIRECTLINK ?
 161                          "on" : "off"),
 162                         batman_ogm_packet->ttvn, hard_iface->net_dev->name,
 163                         hard_iface->net_dev->dev_addr);
 164
 165                 buff_pos += BATMAN_OGM_HLEN +
 166                                 tt_len(batman_ogm_packet->tt_num_changes);
 167                 packet_num++;
 168                 batman_ogm_packet = (struct batman_ogm_packet *)
 169                                         (forw_packet->skb->data + buff_pos);
 170         }
 171
 172         /* create clone because function is called more than once */
 173         skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
 174         if (skb)
 175                 send_skb_packet(skb, hard_iface, broadcast_addr);
 176 }
 177
 178 /* send a batman ogm packet */
 179 static void bat_iv_ogm_emit(struct forw_packet *forw_packet)
 180 {
 181         struct hard_iface *hard_iface;
 182         struct net_device *soft_iface;
 183         struct bat_priv *bat_priv;
 184         struct hard_iface *primary_if = NULL;
 185         struct batman_ogm_packet *batman_ogm_packet;
 186         unsigned char directlink;
 187
 188         batman_ogm_packet = (struct batman_ogm_packet *)
 189                                                 (forw_packet->skb->data);
 190         directlink = (batman_ogm_packet->flags & DIRECTLINK ? 1 : 0);
 191
 192         if (!forw_packet->if_incoming) {
 193                 pr_err("Error - can't forward packet: incoming iface not specified\n");
 194                 goto out;
 195         }
 196
 197         soft_iface = forw_packet->if_incoming->soft_iface;
 198         bat_priv = netdev_priv(soft_iface);
 199
 200         if (forw_packet->if_incoming->if_status != IF_ACTIVE)
 201                 goto out;
 202
 203         primary_if = primary_if_get_selected(bat_priv);
 204         if (!primary_if)
 205                 goto out;
 206
 207         /* multihomed peer assumed */
 208         /* non-primary OGMs are only broadcasted on their interface */
 209         if ((directlink && (batman_ogm_packet->header.ttl == 1)) ||
 210             (forw_packet->own && (forw_packet->if_incoming != primary_if))) {
 211
 212                 /* FIXME: what about aggregated packets ? */
 213                 bat_dbg(DBG_BATMAN, bat_priv,
 214                         "%s packet (originator %pM, seqno %u, TTL %d) on interface %s [%pM]\n",
 215                         (forw_packet->own ? "Sending own" : "Forwarding"),
 216                         batman_ogm_packet->orig,
 217                         ntohl(batman_ogm_packet->seqno),
 218                         batman_ogm_packet->header.ttl,
 219                         forw_packet->if_incoming->net_dev->name,
 220                         forw_packet->if_incoming->net_dev->dev_addr);
 221
 222                 /* skb is only used once and than forw_packet is free'd */
 223                 send_skb_packet(forw_packet->skb, forw_packet->if_incoming,
 224                                 broadcast_addr);
 225                 forw_packet->skb = NULL;
 226
 227                 goto out;
 228         }
 229
 230         /* broadcast on every interface */
 231         rcu_read_lock();
 232         list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
 233                 if (hard_iface->soft_iface != soft_iface)
 234                         continue;
 235
 236                 bat_iv_ogm_send_to_if(forw_packet, hard_iface);
 237         }
 238         rcu_read_unlock();
 239
 240 out:
 241         if (primary_if)
 242                 hardif_free_ref(primary_if);
 243 }
 244
 245 /* return true if new_packet can be aggregated with forw_packet */
 246 static bool bat_iv_ogm_can_aggregate(const struct batman_ogm_packet
 247                                                         *new_batman_ogm_packet,
 248                                      struct bat_priv *bat_priv,
 249                                      int packet_len, unsigned long send_time,
 250                                      bool directlink,
 251                                      const struct hard_iface *if_incoming,
 252                                      const struct forw_packet *forw_packet)
 253 {
 254         struct batman_ogm_packet *batman_ogm_packet;
 255         int aggregated_bytes = forw_packet->packet_len + packet_len;
 256         struct hard_iface *primary_if = NULL;
 257         bool res = false;
 258
 259         batman_ogm_packet = (struct batman_ogm_packet *)forw_packet->skb->data;
 260
 261         /**
 262          * we can aggregate the current packet to this aggregated packet
 263          * if:
 264          *
 265          * - the send time is within our MAX_AGGREGATION_MS time
 266          * - the resulting packet wont be bigger than
 267          *   MAX_AGGREGATION_BYTES
 268          */
 269
 270         if (time_before(send_time, forw_packet->send_time) &&
 271             time_after_eq(send_time + msecs_to_jiffies(MAX_AGGREGATION_MS),
 272                                         forw_packet->send_time) &&
 273             (aggregated_bytes <= MAX_AGGREGATION_BYTES)) {
 274
 275                 /**
 276                  * check aggregation compatibility
 277                  * -> direct link packets are broadcasted on
 278                  *    their interface only
 279                  * -> aggregate packet if the current packet is
 280                  *    a "global" packet as well as the base
 281                  *    packet
 282                  */
 283
 284                 primary_if = primary_if_get_selected(bat_priv);
 285                 if (!primary_if)
 286                         goto out;
 287
 288                 /* packets without direct link flag and high TTL
 289                  * are flooded through the net  */
 290                 if ((!directlink) &&
 291                     (!(batman_ogm_packet->flags & DIRECTLINK)) &&
 292                     (batman_ogm_packet->header.ttl != 1) &&
 293
 294                     /* own packets originating non-primary
 295                      * interfaces leave only that interface */
 296                     ((!forw_packet->own) ||
 297                      (forw_packet->if_incoming == primary_if))) {
 298                         res = true;
 299                         goto out;
 300                 }
 301
 302                 /* if the incoming packet is sent via this one
 303                  * interface only - we still can aggregate */
 304                 if ((directlink) &&
 305                     (new_batman_ogm_packet->header.ttl == 1) &&
 306                     (forw_packet->if_incoming == if_incoming) &&
 307
 308                     /* packets from direct neighbors or
 309                      * own secondary interface packets
 310                      * (= secondary interface packets in general) */
 311                     (batman_ogm_packet->flags & DIRECTLINK ||
 312                      (forw_packet->own &&
 313                       forw_packet->if_incoming != primary_if))) {
 314                         res = true;
 315                         goto out;
 316                 }
 317         }
 318
 319 out:
 320         if (primary_if)
 321                 hardif_free_ref(primary_if);
 322         return res;
 323 }
 324
 325 /* create a new aggregated packet and add this packet to it */
 326 static void bat_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 327                                      int packet_len, unsigned long send_time,
 328                                      bool direct_link,
 329                                      struct hard_iface *if_incoming,
 330                                      int own_packet)
 331 {
 332         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 333         struct forw_packet *forw_packet_aggr;
 334         unsigned char *skb_buff;
 335
 336         if (!atomic_inc_not_zero(&if_incoming->refcount))
 337                 return;
 338
 339         /* own packet should always be scheduled */
 340         if (!own_packet) {
 341                 if (!atomic_dec_not_zero(&bat_priv->batman_queue_left)) {
 342                         bat_dbg(DBG_BATMAN, bat_priv,
 343                                 "batman packet queue full\n");
 344                         goto out;
 345                 }
 346         }
 347
 348         forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC);
 349         if (!forw_packet_aggr) {
 350                 if (!own_packet)
 351                         atomic_inc(&bat_priv->batman_queue_left);
 352                 goto out;
 353         }
 354
 355         if ((atomic_read(&bat_priv->aggregated_ogms)) &&
 356             (packet_len < MAX_AGGREGATION_BYTES))
 357                 forw_packet_aggr->skb = dev_alloc_skb(MAX_AGGREGATION_BYTES +
 358                                                       ETH_HLEN);
 359         else
 360                 forw_packet_aggr->skb = dev_alloc_skb(packet_len + ETH_HLEN);
 361
 362         if (!forw_packet_aggr->skb) {
 363                 if (!own_packet)
 364                         atomic_inc(&bat_priv->batman_queue_left);
 365                 kfree(forw_packet_aggr);
 366                 goto out;
 367         }
 368         skb_reserve(forw_packet_aggr->skb, ETH_HLEN);
 369
 370         INIT_HLIST_NODE(&forw_packet_aggr->list);
 371
 372         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 373         forw_packet_aggr->packet_len = packet_len;
 374         memcpy(skb_buff, packet_buff, packet_len);
 375
 376         forw_packet_aggr->own = own_packet;
 377         forw_packet_aggr->if_incoming = if_incoming;
 378         forw_packet_aggr->num_packets = 0;
 379         forw_packet_aggr->direct_link_flags = NO_FLAGS;
 380         forw_packet_aggr->send_time = send_time;
 381
 382         /* save packet direct link flag status */
 383         if (direct_link)
 384                 forw_packet_aggr->direct_link_flags |= 1;
 385
 386         /* add new packet to packet list */
 387         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 388         hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
 389         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 390
 391         /* start timer for this packet */
 392         INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
 393                           send_outstanding_bat_ogm_packet);
 394         queue_delayed_work(bat_event_workqueue,
 395                            &forw_packet_aggr->delayed_work,
 396                            send_time - jiffies);
 397
 398         return;
 399 out:
 400         hardif_free_ref(if_incoming);
 401 }
 402
 403 /* aggregate a new packet into the existing ogm packet */
 404 static void bat_iv_ogm_aggregate(struct forw_packet *forw_packet_aggr,
 405                                  const unsigned char *packet_buff,
 406                                  int packet_len, bool direct_link)
 407 {
 408         unsigned char *skb_buff;
 409
 410         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 411         memcpy(skb_buff, packet_buff, packet_len);
 412         forw_packet_aggr->packet_len += packet_len;
 413         forw_packet_aggr->num_packets++;
 414
 415         /* save packet direct link flag status */
 416         if (direct_link)
 417                 forw_packet_aggr->direct_link_flags |=
 418                         (1 << forw_packet_aggr->num_packets);
 419 }
 420
 421 static void bat_iv_ogm_queue_add(struct bat_priv *bat_priv,
 422                                  unsigned char *packet_buff,
 423                                  int packet_len, struct hard_iface *if_incoming,
 424                                  int own_packet, unsigned long send_time)
 425 {
 426         /**
 427          * _aggr -> pointer to the packet we want to aggregate with
 428          * _pos -> pointer to the position in the queue
 429          */
 430         struct forw_packet *forw_packet_aggr = NULL, *forw_packet_pos = NULL;
 431         struct hlist_node *tmp_node;
 432         struct batman_ogm_packet *batman_ogm_packet;
 433         bool direct_link;
 434
 435         batman_ogm_packet = (struct batman_ogm_packet *)packet_buff;
 436         direct_link = batman_ogm_packet->flags & DIRECTLINK ? 1 : 0;
 437
 438         /* find position for the packet in the forward queue */
 439         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 440         /* own packets are not to be aggregated */
 441         if ((atomic_read(&bat_priv->aggregated_ogms)) && (!own_packet)) {
 442                 hlist_for_each_entry(forw_packet_pos, tmp_node,
 443                                      &bat_priv->forw_bat_list, list) {
 444                         if (bat_iv_ogm_can_aggregate(batman_ogm_packet,
 445                                                      bat_priv, packet_len,
 446                                                      send_time, direct_link,
 447                                                      if_incoming,
 448                                                      forw_packet_pos)) {
 449                                 forw_packet_aggr = forw_packet_pos;
 450                                 break;
 451                         }
 452                 }
 453         }
 454
 455         /* nothing to aggregate with - either aggregation disabled or no
 456          * suitable aggregation packet found */
 457         if (!forw_packet_aggr) {
 458                 /* the following section can run without the lock */
 459                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 460
 461                 /**
 462                  * if we could not aggregate this packet with one of the others
 463                  * we hold it back for a while, so that it might be aggregated
 464                  * later on
 465                  */
 466                 if ((!own_packet) &&
 467                     (atomic_read(&bat_priv->aggregated_ogms)))
 468                         send_time += msecs_to_jiffies(MAX_AGGREGATION_MS);
 469
 470                 bat_iv_ogm_aggregate_new(packet_buff, packet_len,
 471                                          send_time, direct_link,
 472                                          if_incoming, own_packet);
 473         } else {
 474                 bat_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
 475                                      packet_len, direct_link);
 476                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 477         }
 478 }
 479
 480 static void bat_iv_ogm_forward(struct orig_node *orig_node,
 481                                const struct ethhdr *ethhdr,
 482                                struct batman_ogm_packet *batman_ogm_packet,
 483                                bool is_single_hop_neigh,
 484                                struct hard_iface *if_incoming)
 485 {
 486         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 487         struct neigh_node *router;
 488         uint8_t in_tq, in_ttl, tq_avg = 0;
 489         uint8_t tt_num_changes;
 490
 491         if (batman_ogm_packet->header.ttl <= 1) {
 492                 bat_dbg(DBG_BATMAN, bat_priv, "ttl exceeded\n");
 493                 return;
 494         }
 495
 496         router = orig_node_get_router(orig_node);
 497
 498         in_tq = batman_ogm_packet->tq;
 499         in_ttl = batman_ogm_packet->header.ttl;
 500         tt_num_changes = batman_ogm_packet->tt_num_changes;
 501
 502         batman_ogm_packet->header.ttl--;
 503         memcpy(batman_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
 504
 505         /* rebroadcast tq of our best ranking neighbor to ensure the rebroadcast
 506          * of our best tq value */
 507         if (router && router->tq_avg != 0) {
 508
 509                 /* rebroadcast ogm of best ranking neighbor as is */
 510                 if (!compare_eth(router->addr, ethhdr->h_source)) {
 511                         batman_ogm_packet->tq = router->tq_avg;
 512
 513                         if (router->last_ttl)
 514                                 batman_ogm_packet->header.ttl =
 515                                         router->last_ttl - 1;
 516                 }
 517
 518                 tq_avg = router->tq_avg;
 519         }
 520
 521         if (router)
 522                 neigh_node_free_ref(router);
 523
 524         /* apply hop penalty */
 525         batman_ogm_packet->tq = hop_penalty(batman_ogm_packet->tq, bat_priv);
 526
 527         bat_dbg(DBG_BATMAN, bat_priv,
 528                 "Forwarding packet: tq_orig: %i, tq_avg: %i, tq_forw: %i, ttl_orig: %i, ttl_forw: %i\n",
 529                 in_tq, tq_avg, batman_ogm_packet->tq, in_ttl - 1,
 530                 batman_ogm_packet->header.ttl);
 531
 532         batman_ogm_packet->seqno = htonl(batman_ogm_packet->seqno);
 533         batman_ogm_packet->tt_crc = htons(batman_ogm_packet->tt_crc);
 534
 535         /* switch of primaries first hop flag when forwarding */
 536         batman_ogm_packet->flags &= ~PRIMARIES_FIRST_HOP;
 537         if (is_single_hop_neigh)
 538                 batman_ogm_packet->flags |= DIRECTLINK;
 539         else
 540                 batman_ogm_packet->flags &= ~DIRECTLINK;
 541
 542         bat_iv_ogm_queue_add(bat_priv, (unsigned char *)batman_ogm_packet,
 543                              BATMAN_OGM_HLEN + tt_len(tt_num_changes),
 544                              if_incoming, 0, bat_iv_ogm_fwd_send_time());
 545 }
 546
 547 static void bat_iv_ogm_schedule(struct hard_iface *hard_iface,
 548                                 int tt_num_changes)
 549 {
 550         struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 551         struct batman_ogm_packet *batman_ogm_packet;
 552         struct hard_iface *primary_if;
 553         int vis_server;
 554
 555         vis_server = atomic_read(&bat_priv->vis_mode);
 556         primary_if = primary_if_get_selected(bat_priv);
 557
 558         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
 559
 560         /* change sequence number to network order */
 561         batman_ogm_packet->seqno =
 562                         htonl((uint32_t)atomic_read(&hard_iface->seqno));
 563
 564         batman_ogm_packet->ttvn = atomic_read(&bat_priv->ttvn);
 565         batman_ogm_packet->tt_crc = htons((uint16_t)
 566                                                 atomic_read(&bat_priv->tt_crc));
 567         if (tt_num_changes >= 0)
 568                 batman_ogm_packet->tt_num_changes = tt_num_changes;
 569
 570         if (vis_server == VIS_TYPE_SERVER_SYNC)
 571                 batman_ogm_packet->flags |= VIS_SERVER;
 572         else
 573                 batman_ogm_packet->flags &= ~VIS_SERVER;
 574
 575         if ((hard_iface == primary_if) &&
 576             (atomic_read(&bat_priv->gw_mode) == GW_MODE_SERVER))
 577                 batman_ogm_packet->gw_flags =
 578                                 (uint8_t)atomic_read(&bat_priv->gw_bandwidth);
 579         else
 580                 batman_ogm_packet->gw_flags = NO_FLAGS;
 581
 582         atomic_inc(&hard_iface->seqno);
 583
 584         slide_own_bcast_window(hard_iface);
 585         bat_iv_ogm_queue_add(bat_priv, hard_iface->packet_buff,
 586                              hard_iface->packet_len, hard_iface, 1,
 587                              bat_iv_ogm_emit_send_time(bat_priv));
 588
 589         if (primary_if)
 590                 hardif_free_ref(primary_if);
 591 }
 592
 593 static void bat_iv_ogm_orig_update(struct bat_priv *bat_priv,
 594                                    struct orig_node *orig_node,
 595                                    const struct ethhdr *ethhdr,
 596                                    const struct batman_ogm_packet
 597                                                         *batman_ogm_packet,
 598                                    struct hard_iface *if_incoming,
 599                                    const unsigned char *tt_buff,
 600                                    int is_duplicate)
 601 {
 602         struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 603         struct neigh_node *router = NULL;
 604         struct orig_node *orig_node_tmp;
 605         struct hlist_node *node;
 606         uint8_t bcast_own_sum_orig, bcast_own_sum_neigh;
 607
 608         bat_dbg(DBG_BATMAN, bat_priv,
 609                 "update_originator(): Searching and updating originator entry of received packet\n");
 610
 611         rcu_read_lock();
 612         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 613                                  &orig_node->neigh_list, list) {
 614                 if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) &&
 615                     (tmp_neigh_node->if_incoming == if_incoming) &&
 616                      atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
 617                         if (neigh_node)
 618                                 neigh_node_free_ref(neigh_node);
 619                         neigh_node = tmp_neigh_node;
 620                         continue;
 621                 }
 622
 623                 if (is_duplicate)
 624                         continue;
 625
 626                 spin_lock_bh(&tmp_neigh_node->tq_lock);
 627                 ring_buffer_set(tmp_neigh_node->tq_recv,
 628                                 &tmp_neigh_node->tq_index, 0);
 629                 tmp_neigh_node->tq_avg =
 630                         ring_buffer_avg(tmp_neigh_node->tq_recv);
 631                 spin_unlock_bh(&tmp_neigh_node->tq_lock);
 632         }
 633
 634         if (!neigh_node) {
 635                 struct orig_node *orig_tmp;
 636
 637                 orig_tmp = get_orig_node(bat_priv, ethhdr->h_source);
 638                 if (!orig_tmp)
 639                         goto unlock;
 640
 641                 neigh_node = create_neighbor(orig_node, orig_tmp,
 642                                              ethhdr->h_source, if_incoming);
 643
 644                 orig_node_free_ref(orig_tmp);
 645                 if (!neigh_node)
 646                         goto unlock;
 647         } else
 648                 bat_dbg(DBG_BATMAN, bat_priv,
 649                         "Updating existing last-hop neighbor of originator\n");
 650
 651         rcu_read_unlock();
 652
 653         orig_node->flags = batman_ogm_packet->flags;
 654         neigh_node->last_valid = jiffies;
 655
 656         spin_lock_bh(&neigh_node->tq_lock);
 657         ring_buffer_set(neigh_node->tq_recv,
 658                         &neigh_node->tq_index,
 659                         batman_ogm_packet->tq);
 660         neigh_node->tq_avg = ring_buffer_avg(neigh_node->tq_recv);
 661         spin_unlock_bh(&neigh_node->tq_lock);
 662
 663         if (!is_duplicate) {
 664                 orig_node->last_ttl = batman_ogm_packet->header.ttl;
 665                 neigh_node->last_ttl = batman_ogm_packet->header.ttl;
 666         }
 667
 668         bonding_candidate_add(orig_node, neigh_node);
 669
 670         /* if this neighbor already is our next hop there is nothing
 671          * to change */
 672         router = orig_node_get_router(orig_node);
 673         if (router == neigh_node)
 674                 goto update_tt;
 675
 676         /* if this neighbor does not offer a better TQ we won't consider it */
 677         if (router && (router->tq_avg > neigh_node->tq_avg))
 678                 goto update_tt;
 679
 680         /* if the TQ is the same and the link not more symmetric we
 681          * won't consider it either */
 682         if (router && (neigh_node->tq_avg == router->tq_avg)) {
 683                 orig_node_tmp = router->orig_node;
 684                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 685                 bcast_own_sum_orig =
 686                         orig_node_tmp->bcast_own_sum[if_incoming->if_num];
 687                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 688
 689                 orig_node_tmp = neigh_node->orig_node;
 690                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 691                 bcast_own_sum_neigh =
 692                         orig_node_tmp->bcast_own_sum[if_incoming->if_num];
 693                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 694
 695                 if (bcast_own_sum_orig >= bcast_own_sum_neigh)
 696                         goto update_tt;
 697         }
 698
 699         update_route(bat_priv, orig_node, neigh_node);
 700
 701 update_tt:
 702         /* I have to check for transtable changes only if the OGM has been
 703          * sent through a primary interface */
 704         if (((batman_ogm_packet->orig != ethhdr->h_source) &&
 705              (batman_ogm_packet->header.ttl > 2)) ||
 706             (batman_ogm_packet->flags & PRIMARIES_FIRST_HOP))
 707                 tt_update_orig(bat_priv, orig_node, tt_buff,
 708                                batman_ogm_packet->tt_num_changes,
 709                                batman_ogm_packet->ttvn,
 710                                batman_ogm_packet->tt_crc);
 711
 712         if (orig_node->gw_flags != batman_ogm_packet->gw_flags)
 713                 gw_node_update(bat_priv, orig_node,
 714                                batman_ogm_packet->gw_flags);
 715
 716         orig_node->gw_flags = batman_ogm_packet->gw_flags;
 717
 718         /* restart gateway selection if fast or late switching was enabled */
 719         if ((orig_node->gw_flags) &&
 720             (atomic_read(&bat_priv->gw_mode) == GW_MODE_CLIENT) &&
 721             (atomic_read(&bat_priv->gw_sel_class) > 2))
 722                 gw_check_election(bat_priv, orig_node);
 723
 724         goto out;
 725
 726 unlock:
 727         rcu_read_unlock();
 728 out:
 729         if (neigh_node)
 730                 neigh_node_free_ref(neigh_node);
 731         if (router)
 732                 neigh_node_free_ref(router);
 733 }
 734
 735 static int bat_iv_ogm_calc_tq(struct orig_node *orig_node,
 736                               struct orig_node *orig_neigh_node,
 737                               struct batman_ogm_packet *batman_ogm_packet,
 738                               struct hard_iface *if_incoming)
 739 {
 740         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 741         struct neigh_node *neigh_node = NULL, *tmp_neigh_node;
 742         struct hlist_node *node;
 743         uint8_t total_count;
 744         uint8_t orig_eq_count, neigh_rq_count, tq_own;
 745         int tq_asym_penalty, ret = 0;
 746
 747         /* find corresponding one hop neighbor */
 748         rcu_read_lock();
 749         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 750                                  &orig_neigh_node->neigh_list, list) {
 751
 752                 if (!compare_eth(tmp_neigh_node->addr, orig_neigh_node->orig))
 753                         continue;
 754
 755                 if (tmp_neigh_node->if_incoming != if_incoming)
 756                         continue;
 757
 758                 if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
 759                         continue;
 760
 761                 neigh_node = tmp_neigh_node;
 762                 break;
 763         }
 764         rcu_read_unlock();
 765
 766         if (!neigh_node)
 767                 neigh_node = create_neighbor(orig_neigh_node,
 768                                              orig_neigh_node,
 769                                              orig_neigh_node->orig,
 770                                              if_incoming);
 771
 772         if (!neigh_node)
 773                 goto out;
 774
 775         /* if orig_node is direct neighbor update neigh_node last_valid */
 776         if (orig_node == orig_neigh_node)
 777                 neigh_node->last_valid = jiffies;
 778
 779         orig_node->last_valid = jiffies;
 780
 781         /* find packet count of corresponding one hop neighbor */
 782         spin_lock_bh(&orig_node->ogm_cnt_lock);
 783         orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num];
 784         neigh_rq_count = neigh_node->real_packet_count;
 785         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 786
 787         /* pay attention to not get a value bigger than 100 % */
 788         total_count = (orig_eq_count > neigh_rq_count ?
 789                        neigh_rq_count : orig_eq_count);
 790
 791         /* if we have too few packets (too less data) we set tq_own to zero */
 792         /* if we receive too few packets it is not considered bidirectional */
 793         if ((total_count < TQ_LOCAL_BIDRECT_SEND_MINIMUM) ||
 794             (neigh_rq_count < TQ_LOCAL_BIDRECT_RECV_MINIMUM))
 795                 tq_own = 0;
 796         else
 797                 /* neigh_node->real_packet_count is never zero as we
 798                  * only purge old information when getting new
 799                  * information */
 800                 tq_own = (TQ_MAX_VALUE * total_count) / neigh_rq_count;
 801
 802         /* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
 803          * affect the nearly-symmetric links only a little, but
 804          * punishes asymmetric links more.  This will give a value
 805          * between 0 and TQ_MAX_VALUE
 806          */
 807         tq_asym_penalty = TQ_MAX_VALUE - (TQ_MAX_VALUE *
 808                                 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) *
 809                                 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) *
 810                                 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count)) /
 811                                         (TQ_LOCAL_WINDOW_SIZE *
 812                                          TQ_LOCAL_WINDOW_SIZE *
 813                                          TQ_LOCAL_WINDOW_SIZE);
 814
 815         batman_ogm_packet->tq = ((batman_ogm_packet->tq * tq_own
 816                                                         * tq_asym_penalty) /
 817                                                 (TQ_MAX_VALUE * TQ_MAX_VALUE));
 818
 819         bat_dbg(DBG_BATMAN, bat_priv,
 820                 "bidirectional: orig = %-15pM neigh = %-15pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, total tq: %3i\n",
 821                 orig_node->orig, orig_neigh_node->orig, total_count,
 822                 neigh_rq_count, tq_own, tq_asym_penalty, batman_ogm_packet->tq);
 823
 824         /* if link has the minimum required transmission quality
 825          * consider it bidirectional */
 826         if (batman_ogm_packet->tq >= TQ_TOTAL_BIDRECT_LIMIT)
 827                 ret = 1;
 828
 829 out:
 830         if (neigh_node)
 831                 neigh_node_free_ref(neigh_node);
 832         return ret;
 833 }
 834
 835 /* processes a batman packet for all interfaces, adjusts the sequence number and
 836  * finds out whether it is a duplicate.
 837  * returns:
 838  *   1 the packet is a duplicate
 839  *   0 the packet has not yet been received
 840  *  -1 the packet is old and has been received while the seqno window
 841  *     was protected. Caller should drop it.
 842  */
 843 static int bat_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
 844                                     const struct batman_ogm_packet
 845                                                         *batman_ogm_packet,
 846                                     const struct hard_iface *if_incoming)
 847 {
 848         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 849         struct orig_node *orig_node;
 850         struct neigh_node *tmp_neigh_node;
 851         struct hlist_node *node;
 852         int is_duplicate = 0;
 853         int32_t seq_diff;
 854         int need_update = 0;
 855         int set_mark, ret = -1;
 856
 857         orig_node = get_orig_node(bat_priv, batman_ogm_packet->orig);
 858         if (!orig_node)
 859                 return 0;
 860
 861         spin_lock_bh(&orig_node->ogm_cnt_lock);
 862         seq_diff = batman_ogm_packet->seqno - orig_node->last_real_seqno;
 863
 864         /* signalize caller that the packet is to be dropped. */
 865         if (!hlist_empty(&orig_node->neigh_list) &&
 866             window_protected(bat_priv, seq_diff,
 867                              &orig_node->batman_seqno_reset))
 868                 goto out;
 869
 870         rcu_read_lock();
 871         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 872                                  &orig_node->neigh_list, list) {
 873
 874                 is_duplicate |= bat_test_bit(tmp_neigh_node->real_bits,
 875                                              orig_node->last_real_seqno,
 876                                              batman_ogm_packet->seqno);
 877
 878                 if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) &&
 879                     (tmp_neigh_node->if_incoming == if_incoming))
 880                         set_mark = 1;
 881                 else
 882                         set_mark = 0;
 883
 884                 /* if the window moved, set the update flag. */
 885                 need_update |= bit_get_packet(bat_priv,
 886                                               tmp_neigh_node->real_bits,
 887                                               seq_diff, set_mark);
 888
 889                 tmp_neigh_node->real_packet_count =
 890                         bitmap_weight(tmp_neigh_node->real_bits,
 891                                       TQ_LOCAL_WINDOW_SIZE);
 892         }
 893         rcu_read_unlock();
 894
 895         if (need_update) {
 896                 bat_dbg(DBG_BATMAN, bat_priv,
 897                         "updating last_seqno: old %u, new %u\n",
 898                         orig_node->last_real_seqno, batman_ogm_packet->seqno);
 899                 orig_node->last_real_seqno = batman_ogm_packet->seqno;
 900         }
 901
 902         ret = is_duplicate;
 903
 904 out:
 905         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 906         orig_node_free_ref(orig_node);
 907         return ret;
 908 }
 909
 910 static void bat_iv_ogm_process(const struct ethhdr *ethhdr,
 911                                struct batman_ogm_packet *batman_ogm_packet,
 912                                const unsigned char *tt_buff,
 913                                struct hard_iface *if_incoming)
 914 {
 915         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 916         struct hard_iface *hard_iface;
 917         struct orig_node *orig_neigh_node, *orig_node;
 918         struct neigh_node *router = NULL, *router_router = NULL;
 919         struct neigh_node *orig_neigh_router = NULL;
 920         int has_directlink_flag;
 921         int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
 922         int is_broadcast = 0, is_bidirectional;
 923         bool is_single_hop_neigh = false;
 924         int is_duplicate;
 925         uint32_t if_incoming_seqno;
 926
 927         /* Silently drop when the batman packet is actually not a
 928          * correct packet.
 929          *
 930          * This might happen if a packet is padded (e.g. Ethernet has a
 931          * minimum frame length of 64 byte) and the aggregation interprets
 932          * it as an additional length.
 933          *
 934          * TODO: A more sane solution would be to have a bit in the
 935          * batman_ogm_packet to detect whether the packet is the last
 936          * packet in an aggregation.  Here we expect that the padding
 937          * is always zero (or not 0x01)
 938          */
 939         if (batman_ogm_packet->header.packet_type != BAT_IV_OGM)
 940                 return;
 941
 942         /* could be changed by schedule_own_packet() */
 943         if_incoming_seqno = atomic_read(&if_incoming->seqno);
 944
 945         has_directlink_flag = (batman_ogm_packet->flags & DIRECTLINK ? 1 : 0);
 946
 947         if (compare_eth(ethhdr->h_source, batman_ogm_packet->orig))
 948                 is_single_hop_neigh = true;
 949
 950         bat_dbg(DBG_BATMAN, bat_priv,
 951                 "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",
 952                 ethhdr->h_source, if_incoming->net_dev->name,
 953                 if_incoming->net_dev->dev_addr, batman_ogm_packet->orig,
 954                 batman_ogm_packet->prev_sender, batman_ogm_packet->seqno,
 955                 batman_ogm_packet->ttvn, batman_ogm_packet->tt_crc,
 956                 batman_ogm_packet->tt_num_changes, batman_ogm_packet->tq,
 957                 batman_ogm_packet->header.ttl,
 958                 batman_ogm_packet->header.version, has_directlink_flag);
 959
 960         rcu_read_lock();
 961         list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
 962                 if (hard_iface->if_status != IF_ACTIVE)
 963                         continue;
 964
 965                 if (hard_iface->soft_iface != if_incoming->soft_iface)
 966                         continue;
 967
 968                 if (compare_eth(ethhdr->h_source,
 969                                 hard_iface->net_dev->dev_addr))
 970                         is_my_addr = 1;
 971
 972                 if (compare_eth(batman_ogm_packet->orig,
 973                                 hard_iface->net_dev->dev_addr))
 974                         is_my_orig = 1;
 975
 976                 if (compare_eth(batman_ogm_packet->prev_sender,
 977                                 hard_iface->net_dev->dev_addr))
 978                         is_my_oldorig = 1;
 979
 980                 if (is_broadcast_ether_addr(ethhdr->h_source))
 981                         is_broadcast = 1;
 982         }
 983         rcu_read_unlock();
 984
 985         if (batman_ogm_packet->header.version != COMPAT_VERSION) {
 986                 bat_dbg(DBG_BATMAN, bat_priv,
 987                         "Drop packet: incompatible batman version (%i)\n",
 988                         batman_ogm_packet->header.version);
 989                 return;
 990         }
 991
 992         if (is_my_addr) {
 993                 bat_dbg(DBG_BATMAN, bat_priv,
 994                         "Drop packet: received my own broadcast (sender: %pM)\n",
 995                         ethhdr->h_source);
 996                 return;
 997         }
 998
 999         if (is_broadcast) {
1000                 bat_dbg(DBG_BATMAN, bat_priv,
1001                         "Drop packet: ignoring all packets with broadcast source addr (sender: %pM)\n",
1002                         ethhdr->h_source);
1003                 return;
1004         }
1005
1006         if (is_my_orig) {
1007                 unsigned long *word;
1008                 int offset;
1009
1010                 orig_neigh_node = get_orig_node(bat_priv, ethhdr->h_source);
1011                 if (!orig_neigh_node)
1012                         return;
1013
1014                 /* neighbor has to indicate direct link and it has to
1015                  * come via the corresponding interface */
1016                 /* save packet seqno for bidirectional check */
1017                 if (has_directlink_flag &&
1018                     compare_eth(if_incoming->net_dev->dev_addr,
1019                                 batman_ogm_packet->orig)) {
1020                         offset = if_incoming->if_num * NUM_WORDS;
1021
1022                         spin_lock_bh(&orig_neigh_node->ogm_cnt_lock);
1023                         word = &(orig_neigh_node->bcast_own[offset]);
1024                         bat_set_bit(word,
1025                                     if_incoming_seqno -
1026                                                 batman_ogm_packet->seqno - 2);
1027                         orig_neigh_node->bcast_own_sum[if_incoming->if_num] =
1028                                 bitmap_weight(word, TQ_LOCAL_WINDOW_SIZE);
1029                         spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);
1030                 }
1031
1032                 bat_dbg(DBG_BATMAN, bat_priv,
1033                         "Drop packet: originator packet from myself (via neighbor)\n");
1034                 orig_node_free_ref(orig_neigh_node);
1035                 return;
1036         }
1037
1038         if (is_my_oldorig) {
1039                 bat_dbg(DBG_BATMAN, bat_priv,
1040                         "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
1041                         ethhdr->h_source);
1042                 return;
1043         }
1044
1045         orig_node = get_orig_node(bat_priv, batman_ogm_packet->orig);
1046         if (!orig_node)
1047                 return;
1048
1049         is_duplicate = bat_iv_ogm_update_seqnos(ethhdr, batman_ogm_packet,
1050                                                 if_incoming);
1051
1052         if (is_duplicate == -1) {
1053                 bat_dbg(DBG_BATMAN, bat_priv,
1054                         "Drop packet: packet within seqno protection time (sender: %pM)\n",
1055                         ethhdr->h_source);
1056                 goto out;
1057         }
1058
1059         if (batman_ogm_packet->tq == 0) {
1060                 bat_dbg(DBG_BATMAN, bat_priv,
1061                         "Drop packet: originator packet with tq equal 0\n");
1062                 goto out;
1063         }
1064
1065         router = orig_node_get_router(orig_node);
1066         if (router)
1067                 router_router = orig_node_get_router(router->orig_node);
1068
1069         /* avoid temporary routing loops */
1070         if (router && router_router &&
1071             (compare_eth(router->addr, batman_ogm_packet->prev_sender)) &&
1072             !(compare_eth(batman_ogm_packet->orig,
1073                           batman_ogm_packet->prev_sender)) &&
1074             (compare_eth(router->addr, router_router->addr))) {
1075                 bat_dbg(DBG_BATMAN, bat_priv,
1076                         "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
1077                         ethhdr->h_source);
1078                 goto out;
1079         }
1080
1081         /* if sender is a direct neighbor the sender mac equals
1082          * originator mac */
1083         orig_neigh_node = (is_single_hop_neigh ?
1084                            orig_node :
1085                            get_orig_node(bat_priv, ethhdr->h_source));
1086         if (!orig_neigh_node)
1087                 goto out;
1088
1089         orig_neigh_router = orig_node_get_router(orig_neigh_node);
1090
1091         /* drop packet if sender is not a direct neighbor and if we
1092          * don't route towards it */
1093         if (!is_single_hop_neigh && (!orig_neigh_router)) {
1094                 bat_dbg(DBG_BATMAN, bat_priv,
1095                         "Drop packet: OGM via unknown neighbor!\n");
1096                 goto out_neigh;
1097         }
1098
1099         is_bidirectional = bat_iv_ogm_calc_tq(orig_node, orig_neigh_node,
1100                                               batman_ogm_packet, if_incoming);
1101
1102         bonding_save_primary(orig_node, orig_neigh_node, batman_ogm_packet);
1103
1104         /* update ranking if it is not a duplicate or has the same
1105          * seqno and similar ttl as the non-duplicate */
1106         if (is_bidirectional &&
1107             (!is_duplicate ||
1108              ((orig_node->last_real_seqno == batman_ogm_packet->seqno) &&
1109               (orig_node->last_ttl - 3 <= batman_ogm_packet->header.ttl))))
1110                 bat_iv_ogm_orig_update(bat_priv, orig_node, ethhdr,
1111                                        batman_ogm_packet, if_incoming,
1112                                        tt_buff, is_duplicate);
1113
1114         /* is single hop (direct) neighbor */
1115         if (is_single_hop_neigh) {
1116
1117                 /* mark direct link on incoming interface */
1118                 bat_iv_ogm_forward(orig_node, ethhdr, batman_ogm_packet,
1119                                    is_single_hop_neigh, if_incoming);
1120
1121                 bat_dbg(DBG_BATMAN, bat_priv,
1122                         "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
1123                 goto out_neigh;
1124         }
1125
1126         /* multihop originator */
1127         if (!is_bidirectional) {
1128                 bat_dbg(DBG_BATMAN, bat_priv,
1129                         "Drop packet: not received via bidirectional link\n");
1130                 goto out_neigh;
1131         }
1132
1133         if (is_duplicate) {
1134                 bat_dbg(DBG_BATMAN, bat_priv,
1135                         "Drop packet: duplicate packet received\n");
1136                 goto out_neigh;
1137         }
1138
1139         bat_dbg(DBG_BATMAN, bat_priv,
1140                 "Forwarding packet: rebroadcast originator packet\n");
1141         bat_iv_ogm_forward(orig_node, ethhdr, batman_ogm_packet,
1142                            is_single_hop_neigh, if_incoming);
1143
1144 out_neigh:
1145         if ((orig_neigh_node) && (!is_single_hop_neigh))
1146                 orig_node_free_ref(orig_neigh_node);
1147 out:
1148         if (router)
1149                 neigh_node_free_ref(router);
1150         if (router_router)
1151                 neigh_node_free_ref(router_router);
1152         if (orig_neigh_router)
1153                 neigh_node_free_ref(orig_neigh_router);
1154
1155         orig_node_free_ref(orig_node);
1156 }
1157
1158 static int bat_iv_ogm_receive(struct sk_buff *skb,
1159                               struct hard_iface *if_incoming)
1160 {
1161         struct batman_ogm_packet *batman_ogm_packet;
1162         struct ethhdr *ethhdr;
1163         int buff_pos = 0, packet_len;
1164         unsigned char *tt_buff, *packet_buff;
1165         bool ret;
1166
1167         ret = check_management_packet(skb, if_incoming, BATMAN_OGM_HLEN);
1168         if (!ret)
1169                 return NET_RX_DROP;
1170
1171         packet_len = skb_headlen(skb);
1172         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1173         packet_buff = skb->data;
1174         batman_ogm_packet = (struct batman_ogm_packet *)packet_buff;
1175
1176         /* unpack the aggregated packets and process them one by one */
1177         do {
1178                 /* network to host order for our 32bit seqno and the
1179                    orig_interval */
1180                 batman_ogm_packet->seqno = ntohl(batman_ogm_packet->seqno);
1181                 batman_ogm_packet->tt_crc = ntohs(batman_ogm_packet->tt_crc);
1182
1183                 tt_buff = packet_buff + buff_pos + BATMAN_OGM_HLEN;
1184
1185                 bat_iv_ogm_process(ethhdr, batman_ogm_packet,
1186                                    tt_buff, if_incoming);
1187
1188                 buff_pos += BATMAN_OGM_HLEN +
1189                                 tt_len(batman_ogm_packet->tt_num_changes);
1190
1191                 batman_ogm_packet = (struct batman_ogm_packet *)
1192                                                 (packet_buff + buff_pos);
1193         } while (bat_iv_ogm_aggr_packet(buff_pos, packet_len,
1194                                         batman_ogm_packet->tt_num_changes));
1195
1196         kfree_skb(skb);
1197         return NET_RX_SUCCESS;
1198 }
1199
1200 static struct bat_algo_ops batman_iv __read_mostly = {
1201         .name = "BATMAN IV",
1202         .bat_iface_enable = bat_iv_ogm_iface_enable,
1203         .bat_iface_disable = bat_iv_ogm_iface_disable,
1204         .bat_primary_iface_set = bat_iv_ogm_primary_iface_set,
1205         .bat_ogm_update_mac = bat_iv_ogm_update_mac,
1206         .bat_ogm_schedule = bat_iv_ogm_schedule,
1207         .bat_ogm_emit = bat_iv_ogm_emit,
1208 };
1209
1210 int __init bat_iv_init(void)
1211 {
1212         int ret;
1213
1214         /* batman originator packet */
1215         ret = recv_handler_register(BAT_IV_OGM, bat_iv_ogm_receive);
1216         if (ret < 0)
1217                 goto out;
1218
1219         ret = bat_algo_register(&batman_iv);
1220         if (ret < 0)
1221                 goto handler_unregister;
1222
1223         goto out;
1224
1225 handler_unregister:
1226         recv_handler_unregister(BAT_IV_OGM);
1227 out:
1228         return ret;
1229 }