net/batman-adv/bat_iv_ogm.c

   1 /* Copyright (C) 2007-2012 B.A.T.M.A.N. contributors:
   2  *
   3  * Marek Lindner, Simon Wunderlich
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of version 2 of the GNU General Public
   7  * License as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  17  * 02110-1301, USA
  18  */
  19
  20 #include "main.h"
  21 #include "translation-table.h"
  22 #include "ring_buffer.h"
  23 #include "originator.h"
  24 #include "routing.h"
  25 #include "gateway_common.h"
  26 #include "gateway_client.h"
  27 #include "hard-interface.h"
  28 #include "send.h"
  29 #include "bat_algo.h"
  30
  31 static struct neigh_node *batadv_iv_ogm_neigh_new(struct hard_iface *hard_iface,
  32                                                   const uint8_t *neigh_addr,
  33                                                   struct orig_node *orig_node,
  34                                                   struct orig_node *orig_neigh,
  35                                                   __be32 seqno)
  36 {
  37         struct neigh_node *neigh_node;
  38
  39         neigh_node = batadv_neigh_node_new(hard_iface, neigh_addr,
  40                                            ntohl(seqno));
  41         if (!neigh_node)
  42                 goto out;
  43
  44         INIT_LIST_HEAD(&neigh_node->bonding_list);
  45
  46         neigh_node->orig_node = orig_neigh;
  47         neigh_node->if_incoming = hard_iface;
  48
  49         spin_lock_bh(&orig_node->neigh_list_lock);
  50         hlist_add_head_rcu(&neigh_node->list, &orig_node->neigh_list);
  51         spin_unlock_bh(&orig_node->neigh_list_lock);
  52
  53 out:
  54         return neigh_node;
  55 }
  56
  57 static int batadv_iv_ogm_iface_enable(struct hard_iface *hard_iface)
  58 {
  59         struct batman_ogm_packet *batman_ogm_packet;
  60         uint32_t random_seqno;
  61         int res = -ENOMEM;
  62
  63         /* randomize initial seqno to avoid collision */
  64         get_random_bytes(&random_seqno, sizeof(random_seqno));
  65         atomic_set(&hard_iface->seqno, random_seqno);
  66
  67         hard_iface->packet_len = BATADV_OGM_HLEN;
  68         hard_iface->packet_buff = kmalloc(hard_iface->packet_len, GFP_ATOMIC);
  69
  70         if (!hard_iface->packet_buff)
  71                 goto out;
  72
  73         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
  74         batman_ogm_packet->header.packet_type = BAT_IV_OGM;
  75         batman_ogm_packet->header.version = BATADV_COMPAT_VERSION;
  76         batman_ogm_packet->header.ttl = 2;
  77         batman_ogm_packet->flags = BATADV_NO_FLAGS;
  78         batman_ogm_packet->tq = BATADV_TQ_MAX_VALUE;
  79         batman_ogm_packet->tt_num_changes = 0;
  80         batman_ogm_packet->ttvn = 0;
  81
  82         res = 0;
  83
  84 out:
  85         return res;
  86 }
  87
  88 static void batadv_iv_ogm_iface_disable(struct hard_iface *hard_iface)
  89 {
  90         kfree(hard_iface->packet_buff);
  91         hard_iface->packet_buff = NULL;
  92 }
  93
  94 static void batadv_iv_ogm_iface_update_mac(struct hard_iface *hard_iface)
  95 {
  96         struct batman_ogm_packet *batman_ogm_packet;
  97
  98         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
  99         memcpy(batman_ogm_packet->orig,
 100                hard_iface->net_dev->dev_addr, ETH_ALEN);
 101         memcpy(batman_ogm_packet->prev_sender,
 102                hard_iface->net_dev->dev_addr, ETH_ALEN);
 103 }
 104
 105 static void batadv_iv_ogm_primary_iface_set(struct hard_iface *hard_iface)
 106 {
 107         struct batman_ogm_packet *batman_ogm_packet;
 108
 109         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
 110         batman_ogm_packet->flags = PRIMARIES_FIRST_HOP;
 111         batman_ogm_packet->header.ttl = BATADV_TTL;
 112 }
 113
 114 /* when do we schedule our own ogm to be sent */
 115 static unsigned long
 116 batadv_iv_ogm_emit_send_time(const struct bat_priv *bat_priv)
 117 {
 118         unsigned int msecs;
 119
 120         msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
 121         msecs += (random32() % 2 * BATADV_JITTER);
 122
 123         return jiffies + msecs_to_jiffies(msecs);
 124 }
 125
 126 /* when do we schedule a ogm packet to be sent */
 127 static unsigned long batadv_iv_ogm_fwd_send_time(void)
 128 {
 129         return jiffies + msecs_to_jiffies(random32() % (BATADV_JITTER / 2));
 130 }
 131
 132 /* apply hop penalty for a normal link */
 133 static uint8_t batadv_hop_penalty(uint8_t tq, const struct bat_priv *bat_priv)
 134 {
 135         int hop_penalty = atomic_read(&bat_priv->hop_penalty);
 136         int new_tq;
 137
 138         new_tq = tq * (BATADV_TQ_MAX_VALUE - hop_penalty);
 139         new_tq /= BATADV_TQ_MAX_VALUE;
 140
 141         return new_tq;
 142 }
 143
 144 /* is there another aggregated packet here? */
 145 static int batadv_iv_ogm_aggr_packet(int buff_pos, int packet_len,
 146                                      int tt_num_changes)
 147 {
 148         int next_buff_pos = 0;
 149
 150         next_buff_pos += buff_pos + BATADV_OGM_HLEN;
 151         next_buff_pos += batadv_tt_len(tt_num_changes);
 152
 153         return (next_buff_pos <= packet_len) &&
 154                (next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES);
 155 }
 156
 157 /* send a batman ogm to a given interface */
 158 static void batadv_iv_ogm_send_to_if(struct forw_packet *forw_packet,
 159                                   struct hard_iface *hard_iface)
 160 {
 161         struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 162         char *fwd_str;
 163         uint8_t packet_num;
 164         int16_t buff_pos;
 165         struct batman_ogm_packet *batman_ogm_packet;
 166         struct sk_buff *skb;
 167
 168         if (hard_iface->if_status != IF_ACTIVE)
 169                 return;
 170
 171         packet_num = 0;
 172         buff_pos = 0;
 173         batman_ogm_packet = (struct batman_ogm_packet *)forw_packet->skb->data;
 174
 175         /* adjust all flags and log packets */
 176         while (batadv_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
 177                                          batman_ogm_packet->tt_num_changes)) {
 178
 179                 /* we might have aggregated direct link packets with an
 180                  * ordinary base packet
 181                  */
 182                 if ((forw_packet->direct_link_flags & (1 << packet_num)) &&
 183                     (forw_packet->if_incoming == hard_iface))
 184                         batman_ogm_packet->flags |= DIRECTLINK;
 185                 else
 186                         batman_ogm_packet->flags &= ~DIRECTLINK;
 187
 188                 fwd_str = (packet_num > 0 ? "Forwarding" : (forw_packet->own ?
 189                                                             "Sending own" :
 190                                                             "Forwarding"));
 191                 batadv_dbg(DBG_BATMAN, bat_priv,
 192                            "%s %spacket (originator %pM, seqno %u, TQ %d, TTL %d, IDF %s, ttvn %d) on interface %s [%pM]\n",
 193                            fwd_str, (packet_num > 0 ? "aggregated " : ""),
 194                            batman_ogm_packet->orig,
 195                            ntohl(batman_ogm_packet->seqno),
 196                            batman_ogm_packet->tq, batman_ogm_packet->header.ttl,
 197                            (batman_ogm_packet->flags & DIRECTLINK ?
 198                             "on" : "off"),
 199                            batman_ogm_packet->ttvn, hard_iface->net_dev->name,
 200                            hard_iface->net_dev->dev_addr);
 201
 202                 buff_pos += BATADV_OGM_HLEN;
 203                 buff_pos += batadv_tt_len(batman_ogm_packet->tt_num_changes);
 204                 packet_num++;
 205                 batman_ogm_packet = (struct batman_ogm_packet *)
 206                                         (forw_packet->skb->data + buff_pos);
 207         }
 208
 209         /* create clone because function is called more than once */
 210         skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
 211         if (skb) {
 212                 batadv_inc_counter(bat_priv, BAT_CNT_MGMT_TX);
 213                 batadv_add_counter(bat_priv, BAT_CNT_MGMT_TX_BYTES,
 214                                    skb->len + ETH_HLEN);
 215                 batadv_send_skb_packet(skb, hard_iface, batadv_broadcast_addr);
 216         }
 217 }
 218
 219 /* send a batman ogm packet */
 220 static void batadv_iv_ogm_emit(struct forw_packet *forw_packet)
 221 {
 222         struct hard_iface *hard_iface;
 223         struct net_device *soft_iface;
 224         struct bat_priv *bat_priv;
 225         struct hard_iface *primary_if = NULL;
 226         struct batman_ogm_packet *batman_ogm_packet;
 227         unsigned char directlink;
 228
 229         batman_ogm_packet = (struct batman_ogm_packet *)
 230                                                 (forw_packet->skb->data);
 231         directlink = (batman_ogm_packet->flags & DIRECTLINK ? 1 : 0);
 232
 233         if (!forw_packet->if_incoming) {
 234                 pr_err("Error - can't forward packet: incoming iface not specified\n");
 235                 goto out;
 236         }
 237
 238         soft_iface = forw_packet->if_incoming->soft_iface;
 239         bat_priv = netdev_priv(soft_iface);
 240
 241         if (forw_packet->if_incoming->if_status != IF_ACTIVE)
 242                 goto out;
 243
 244         primary_if = batadv_primary_if_get_selected(bat_priv);
 245         if (!primary_if)
 246                 goto out;
 247
 248         /* multihomed peer assumed
 249          * non-primary OGMs are only broadcasted on their interface
 250          */
 251         if ((directlink && (batman_ogm_packet->header.ttl == 1)) ||
 252             (forw_packet->own && (forw_packet->if_incoming != primary_if))) {
 253
 254                 /* FIXME: what about aggregated packets ? */
 255                 batadv_dbg(DBG_BATMAN, bat_priv,
 256                            "%s packet (originator %pM, seqno %u, TTL %d) on interface %s [%pM]\n",
 257                            (forw_packet->own ? "Sending own" : "Forwarding"),
 258                            batman_ogm_packet->orig,
 259                            ntohl(batman_ogm_packet->seqno),
 260                            batman_ogm_packet->header.ttl,
 261                            forw_packet->if_incoming->net_dev->name,
 262                            forw_packet->if_incoming->net_dev->dev_addr);
 263
 264                 /* skb is only used once and than forw_packet is free'd */
 265                 batadv_send_skb_packet(forw_packet->skb,
 266                                        forw_packet->if_incoming,
 267                                        batadv_broadcast_addr);
 268                 forw_packet->skb = NULL;
 269
 270                 goto out;
 271         }
 272
 273         /* broadcast on every interface */
 274         rcu_read_lock();
 275         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 276                 if (hard_iface->soft_iface != soft_iface)
 277                         continue;
 278
 279                 batadv_iv_ogm_send_to_if(forw_packet, hard_iface);
 280         }
 281         rcu_read_unlock();
 282
 283 out:
 284         if (primary_if)
 285                 batadv_hardif_free_ref(primary_if);
 286 }
 287
 288 /* return true if new_packet can be aggregated with forw_packet */
 289 static bool
 290 batadv_iv_ogm_can_aggregate(const struct batman_ogm_packet *new_bat_ogm_packet,
 291                             struct bat_priv *bat_priv,
 292                             int packet_len, unsigned long send_time,
 293                             bool directlink,
 294                             const struct hard_iface *if_incoming,
 295                             const struct forw_packet *forw_packet)
 296 {
 297         struct batman_ogm_packet *batman_ogm_packet;
 298         int aggregated_bytes = forw_packet->packet_len + packet_len;
 299         struct hard_iface *primary_if = NULL;
 300         bool res = false;
 301         unsigned long aggregation_end_time;
 302
 303         batman_ogm_packet = (struct batman_ogm_packet *)forw_packet->skb->data;
 304         aggregation_end_time = send_time;
 305         aggregation_end_time += msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 306
 307         /* we can aggregate the current packet to this aggregated packet
 308          * if:
 309          *
 310          * - the send time is within our MAX_AGGREGATION_MS time
 311          * - the resulting packet wont be bigger than
 312          *   MAX_AGGREGATION_BYTES
 313          */
 314         if (time_before(send_time, forw_packet->send_time) &&
 315             time_after_eq(aggregation_end_time, forw_packet->send_time) &&
 316             (aggregated_bytes <= BATADV_MAX_AGGREGATION_BYTES)) {
 317
 318                 /* check aggregation compatibility
 319                  * -> direct link packets are broadcasted on
 320                  *    their interface only
 321                  * -> aggregate packet if the current packet is
 322                  *    a "global" packet as well as the base
 323                  *    packet
 324                  */
 325                 primary_if = batadv_primary_if_get_selected(bat_priv);
 326                 if (!primary_if)
 327                         goto out;
 328
 329                 /* packets without direct link flag and high TTL
 330                  * are flooded through the net
 331                  */
 332                 if ((!directlink) &&
 333                     (!(batman_ogm_packet->flags & DIRECTLINK)) &&
 334                     (batman_ogm_packet->header.ttl != 1) &&
 335
 336                     /* own packets originating non-primary
 337                      * interfaces leave only that interface
 338                      */
 339                     ((!forw_packet->own) ||
 340                      (forw_packet->if_incoming == primary_if))) {
 341                         res = true;
 342                         goto out;
 343                 }
 344
 345                 /* if the incoming packet is sent via this one
 346                  * interface only - we still can aggregate
 347                  */
 348                 if ((directlink) &&
 349                     (new_bat_ogm_packet->header.ttl == 1) &&
 350                     (forw_packet->if_incoming == if_incoming) &&
 351
 352                     /* packets from direct neighbors or
 353                      * own secondary interface packets
 354                      * (= secondary interface packets in general)
 355                      */
 356                     (batman_ogm_packet->flags & DIRECTLINK ||
 357                      (forw_packet->own &&
 358                       forw_packet->if_incoming != primary_if))) {
 359                         res = true;
 360                         goto out;
 361                 }
 362         }
 363
 364 out:
 365         if (primary_if)
 366                 batadv_hardif_free_ref(primary_if);
 367         return res;
 368 }
 369
 370 /* create a new aggregated packet and add this packet to it */
 371 static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 372                                         int packet_len, unsigned long send_time,
 373                                         bool direct_link,
 374                                         struct hard_iface *if_incoming,
 375                                         int own_packet)
 376 {
 377         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 378         struct forw_packet *forw_packet_aggr;
 379         unsigned char *skb_buff;
 380         unsigned int skb_size;
 381
 382         if (!atomic_inc_not_zero(&if_incoming->refcount))
 383                 return;
 384
 385         /* own packet should always be scheduled */
 386         if (!own_packet) {
 387                 if (!batadv_atomic_dec_not_zero(&bat_priv->batman_queue_left)) {
 388                         batadv_dbg(DBG_BATMAN, bat_priv,
 389                                    "batman packet queue full\n");
 390                         goto out;
 391                 }
 392         }
 393
 394         forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC);
 395         if (!forw_packet_aggr) {
 396                 if (!own_packet)
 397                         atomic_inc(&bat_priv->batman_queue_left);
 398                 goto out;
 399         }
 400
 401         if ((atomic_read(&bat_priv->aggregated_ogms)) &&
 402             (packet_len < BATADV_MAX_AGGREGATION_BYTES))
 403                 skb_size = BATADV_MAX_AGGREGATION_BYTES + ETH_HLEN;
 404         else
 405                 skb_size = packet_len + ETH_HLEN;
 406
 407         forw_packet_aggr->skb = dev_alloc_skb(skb_size);
 408         if (!forw_packet_aggr->skb) {
 409                 if (!own_packet)
 410                         atomic_inc(&bat_priv->batman_queue_left);
 411                 kfree(forw_packet_aggr);
 412                 goto out;
 413         }
 414         skb_reserve(forw_packet_aggr->skb, ETH_HLEN);
 415
 416         INIT_HLIST_NODE(&forw_packet_aggr->list);
 417
 418         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 419         forw_packet_aggr->packet_len = packet_len;
 420         memcpy(skb_buff, packet_buff, packet_len);
 421
 422         forw_packet_aggr->own = own_packet;
 423         forw_packet_aggr->if_incoming = if_incoming;
 424         forw_packet_aggr->num_packets = 0;
 425         forw_packet_aggr->direct_link_flags = BATADV_NO_FLAGS;
 426         forw_packet_aggr->send_time = send_time;
 427
 428         /* save packet direct link flag status */
 429         if (direct_link)
 430                 forw_packet_aggr->direct_link_flags |= 1;
 431
 432         /* add new packet to packet list */
 433         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 434         hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
 435         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 436
 437         /* start timer for this packet */
 438         INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
 439                           batadv_send_outstanding_bat_ogm_packet);
 440         queue_delayed_work(batadv_event_workqueue,
 441                            &forw_packet_aggr->delayed_work,
 442                            send_time - jiffies);
 443
 444         return;
 445 out:
 446         batadv_hardif_free_ref(if_incoming);
 447 }
 448
 449 /* aggregate a new packet into the existing ogm packet */
 450 static void batadv_iv_ogm_aggregate(struct forw_packet *forw_packet_aggr,
 451                                     const unsigned char *packet_buff,
 452                                     int packet_len, bool direct_link)
 453 {
 454         unsigned char *skb_buff;
 455
 456         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 457         memcpy(skb_buff, packet_buff, packet_len);
 458         forw_packet_aggr->packet_len += packet_len;
 459         forw_packet_aggr->num_packets++;
 460
 461         /* save packet direct link flag status */
 462         if (direct_link)
 463                 forw_packet_aggr->direct_link_flags |=
 464                         (1 << forw_packet_aggr->num_packets);
 465 }
 466
 467 static void batadv_iv_ogm_queue_add(struct bat_priv *bat_priv,
 468                                     unsigned char *packet_buff,
 469                                     int packet_len,
 470                                     struct hard_iface *if_incoming,
 471                                     int own_packet, unsigned long send_time)
 472 {
 473         /* _aggr -> pointer to the packet we want to aggregate with
 474          * _pos -> pointer to the position in the queue
 475          */
 476         struct forw_packet *forw_packet_aggr = NULL, *forw_packet_pos = NULL;
 477         struct hlist_node *tmp_node;
 478         struct batman_ogm_packet *batman_ogm_packet;
 479         bool direct_link;
 480         unsigned long max_aggregation_jiffies;
 481
 482         batman_ogm_packet = (struct batman_ogm_packet *)packet_buff;
 483         direct_link = batman_ogm_packet->flags & DIRECTLINK ? 1 : 0;
 484         max_aggregation_jiffies = msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 485
 486         /* find position for the packet in the forward queue */
 487         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 488         /* own packets are not to be aggregated */
 489         if ((atomic_read(&bat_priv->aggregated_ogms)) && (!own_packet)) {
 490                 hlist_for_each_entry(forw_packet_pos, tmp_node,
 491                                      &bat_priv->forw_bat_list, list) {
 492                         if (batadv_iv_ogm_can_aggregate(batman_ogm_packet,
 493                                                         bat_priv, packet_len,
 494                                                         send_time, direct_link,
 495                                                         if_incoming,
 496                                                         forw_packet_pos)) {
 497                                 forw_packet_aggr = forw_packet_pos;
 498                                 break;
 499                         }
 500                 }
 501         }
 502
 503         /* nothing to aggregate with - either aggregation disabled or no
 504          * suitable aggregation packet found
 505          */
 506         if (!forw_packet_aggr) {
 507                 /* the following section can run without the lock */
 508                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 509
 510                 /* if we could not aggregate this packet with one of the others
 511                  * we hold it back for a while, so that it might be aggregated
 512                  * later on
 513                  */
 514                 if (!own_packet && atomic_read(&bat_priv->aggregated_ogms))
 515                         send_time += max_aggregation_jiffies;
 516
 517                 batadv_iv_ogm_aggregate_new(packet_buff, packet_len,
 518                                             send_time, direct_link,
 519                                             if_incoming, own_packet);
 520         } else {
 521                 batadv_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
 522                                         packet_len, direct_link);
 523                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 524         }
 525 }
 526
 527 static void batadv_iv_ogm_forward(struct orig_node *orig_node,
 528                                   const struct ethhdr *ethhdr,
 529                                   struct batman_ogm_packet *batman_ogm_packet,
 530                                   bool is_single_hop_neigh,
 531                                   bool is_from_best_next_hop,
 532                                   struct hard_iface *if_incoming)
 533 {
 534         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 535         uint8_t tt_num_changes;
 536
 537         if (batman_ogm_packet->header.ttl <= 1) {
 538                 batadv_dbg(DBG_BATMAN, bat_priv, "ttl exceeded\n");
 539                 return;
 540         }
 541
 542         if (!is_from_best_next_hop) {
 543                 /* Mark the forwarded packet when it is not coming from our
 544                  * best next hop. We still need to forward the packet for our
 545                  * neighbor link quality detection to work in case the packet
 546                  * originated from a single hop neighbor. Otherwise we can
 547                  * simply drop the ogm.
 548                  */
 549                 if (is_single_hop_neigh)
 550                         batman_ogm_packet->flags |= NOT_BEST_NEXT_HOP;
 551                 else
 552                         return;
 553         }
 554
 555         tt_num_changes = batman_ogm_packet->tt_num_changes;
 556
 557         batman_ogm_packet->header.ttl--;
 558         memcpy(batman_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
 559
 560         /* apply hop penalty */
 561         batman_ogm_packet->tq = batadv_hop_penalty(batman_ogm_packet->tq,
 562                                                    bat_priv);
 563
 564         batadv_dbg(DBG_BATMAN, bat_priv,
 565                    "Forwarding packet: tq: %i, ttl: %i\n",
 566                    batman_ogm_packet->tq, batman_ogm_packet->header.ttl);
 567
 568         /* switch of primaries first hop flag when forwarding */
 569         batman_ogm_packet->flags &= ~PRIMARIES_FIRST_HOP;
 570         if (is_single_hop_neigh)
 571                 batman_ogm_packet->flags |= DIRECTLINK;
 572         else
 573                 batman_ogm_packet->flags &= ~DIRECTLINK;
 574
 575         batadv_iv_ogm_queue_add(bat_priv, (unsigned char *)batman_ogm_packet,
 576                                 BATADV_OGM_HLEN + batadv_tt_len(tt_num_changes),
 577                                 if_incoming, 0, batadv_iv_ogm_fwd_send_time());
 578 }
 579
 580 static void batadv_iv_ogm_schedule(struct hard_iface *hard_iface)
 581 {
 582         struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 583         struct batman_ogm_packet *batman_ogm_packet;
 584         struct hard_iface *primary_if;
 585         int vis_server, tt_num_changes = 0;
 586
 587         vis_server = atomic_read(&bat_priv->vis_mode);
 588         primary_if = batadv_primary_if_get_selected(bat_priv);
 589
 590         if (hard_iface == primary_if)
 591                 tt_num_changes = batadv_tt_append_diff(bat_priv,
 592                                                        &hard_iface->packet_buff,
 593                                                        &hard_iface->packet_len,
 594                                                        BATADV_OGM_HLEN);
 595
 596         batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
 597
 598         /* change sequence number to network order */
 599         batman_ogm_packet->seqno =
 600                         htonl((uint32_t)atomic_read(&hard_iface->seqno));
 601         atomic_inc(&hard_iface->seqno);
 602
 603         batman_ogm_packet->ttvn = atomic_read(&bat_priv->ttvn);
 604         batman_ogm_packet->tt_crc = htons(bat_priv->tt_crc);
 605         if (tt_num_changes >= 0)
 606                 batman_ogm_packet->tt_num_changes = tt_num_changes;
 607
 608         if (vis_server == VIS_TYPE_SERVER_SYNC)
 609                 batman_ogm_packet->flags |= VIS_SERVER;
 610         else
 611                 batman_ogm_packet->flags &= ~VIS_SERVER;
 612
 613         if ((hard_iface == primary_if) &&
 614             (atomic_read(&bat_priv->gw_mode) == GW_MODE_SERVER))
 615                 batman_ogm_packet->gw_flags =
 616                                 (uint8_t)atomic_read(&bat_priv->gw_bandwidth);
 617         else
 618                 batman_ogm_packet->gw_flags = BATADV_NO_FLAGS;
 619
 620         batadv_slide_own_bcast_window(hard_iface);
 621         batadv_iv_ogm_queue_add(bat_priv, hard_iface->packet_buff,
 622                                 hard_iface->packet_len, hard_iface, 1,
 623                                 batadv_iv_ogm_emit_send_time(bat_priv));
 624
 625         if (primary_if)
 626                 batadv_hardif_free_ref(primary_if);
 627 }
 628
 629 static void
 630 batadv_iv_ogm_orig_update(struct bat_priv *bat_priv,
 631                           struct orig_node *orig_node,
 632                           const struct ethhdr *ethhdr,
 633                           const struct batman_ogm_packet *batman_ogm_packet,
 634                           struct hard_iface *if_incoming,
 635                           const unsigned char *tt_buff,
 636                           int is_duplicate)
 637 {
 638         struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 639         struct neigh_node *router = NULL;
 640         struct orig_node *orig_node_tmp;
 641         struct hlist_node *node;
 642         uint8_t bcast_own_sum_orig, bcast_own_sum_neigh;
 643         uint8_t *neigh_addr;
 644
 645         batadv_dbg(DBG_BATMAN, bat_priv,
 646                    "update_originator(): Searching and updating originator entry of received packet\n");
 647
 648         rcu_read_lock();
 649         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 650                                  &orig_node->neigh_list, list) {
 651                 neigh_addr = tmp_neigh_node->addr;
 652                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
 653                     tmp_neigh_node->if_incoming == if_incoming &&
 654                     atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
 655                         if (neigh_node)
 656                                 batadv_neigh_node_free_ref(neigh_node);
 657                         neigh_node = tmp_neigh_node;
 658                         continue;
 659                 }
 660
 661                 if (is_duplicate)
 662                         continue;
 663
 664                 spin_lock_bh(&tmp_neigh_node->lq_update_lock);
 665                 batadv_ring_buffer_set(tmp_neigh_node->tq_recv,
 666                                        &tmp_neigh_node->tq_index, 0);
 667                 tmp_neigh_node->tq_avg =
 668                         batadv_ring_buffer_avg(tmp_neigh_node->tq_recv);
 669                 spin_unlock_bh(&tmp_neigh_node->lq_update_lock);
 670         }
 671
 672         if (!neigh_node) {
 673                 struct orig_node *orig_tmp;
 674
 675                 orig_tmp = batadv_get_orig_node(bat_priv, ethhdr->h_source);
 676                 if (!orig_tmp)
 677                         goto unlock;
 678
 679                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
 680                                                      ethhdr->h_source,
 681                                                      orig_node, orig_tmp,
 682                                                      batman_ogm_packet->seqno);
 683
 684                 batadv_orig_node_free_ref(orig_tmp);
 685                 if (!neigh_node)
 686                         goto unlock;
 687         } else
 688                 batadv_dbg(DBG_BATMAN, bat_priv,
 689                            "Updating existing last-hop neighbor of originator\n");
 690
 691         rcu_read_unlock();
 692
 693         orig_node->flags = batman_ogm_packet->flags;
 694         neigh_node->last_seen = jiffies;
 695
 696         spin_lock_bh(&neigh_node->lq_update_lock);
 697         batadv_ring_buffer_set(neigh_node->tq_recv,
 698                                &neigh_node->tq_index,
 699                                batman_ogm_packet->tq);
 700         neigh_node->tq_avg = batadv_ring_buffer_avg(neigh_node->tq_recv);
 701         spin_unlock_bh(&neigh_node->lq_update_lock);
 702
 703         if (!is_duplicate) {
 704                 orig_node->last_ttl = batman_ogm_packet->header.ttl;
 705                 neigh_node->last_ttl = batman_ogm_packet->header.ttl;
 706         }
 707
 708         batadv_bonding_candidate_add(orig_node, neigh_node);
 709
 710         /* if this neighbor already is our next hop there is nothing
 711          * to change
 712          */
 713         router = batadv_orig_node_get_router(orig_node);
 714         if (router == neigh_node)
 715                 goto update_tt;
 716
 717         /* if this neighbor does not offer a better TQ we won't consider it */
 718         if (router && (router->tq_avg > neigh_node->tq_avg))
 719                 goto update_tt;
 720
 721         /* if the TQ is the same and the link not more symmetric we
 722          * won't consider it either
 723          */
 724         if (router && (neigh_node->tq_avg == router->tq_avg)) {
 725                 orig_node_tmp = router->orig_node;
 726                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 727                 bcast_own_sum_orig =
 728                         orig_node_tmp->bcast_own_sum[if_incoming->if_num];
 729                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 730
 731                 orig_node_tmp = neigh_node->orig_node;
 732                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 733                 bcast_own_sum_neigh =
 734                         orig_node_tmp->bcast_own_sum[if_incoming->if_num];
 735                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 736
 737                 if (bcast_own_sum_orig >= bcast_own_sum_neigh)
 738                         goto update_tt;
 739         }
 740
 741         batadv_update_route(bat_priv, orig_node, neigh_node);
 742
 743 update_tt:
 744         /* I have to check for transtable changes only if the OGM has been
 745          * sent through a primary interface
 746          */
 747         if (((batman_ogm_packet->orig != ethhdr->h_source) &&
 748              (batman_ogm_packet->header.ttl > 2)) ||
 749             (batman_ogm_packet->flags & PRIMARIES_FIRST_HOP))
 750                 batadv_tt_update_orig(bat_priv, orig_node, tt_buff,
 751                                       batman_ogm_packet->tt_num_changes,
 752                                       batman_ogm_packet->ttvn,
 753                                       ntohs(batman_ogm_packet->tt_crc));
 754
 755         if (orig_node->gw_flags != batman_ogm_packet->gw_flags)
 756                 batadv_gw_node_update(bat_priv, orig_node,
 757                                       batman_ogm_packet->gw_flags);
 758
 759         orig_node->gw_flags = batman_ogm_packet->gw_flags;
 760
 761         /* restart gateway selection if fast or late switching was enabled */
 762         if ((orig_node->gw_flags) &&
 763             (atomic_read(&bat_priv->gw_mode) == GW_MODE_CLIENT) &&
 764             (atomic_read(&bat_priv->gw_sel_class) > 2))
 765                 batadv_gw_check_election(bat_priv, orig_node);
 766
 767         goto out;
 768
 769 unlock:
 770         rcu_read_unlock();
 771 out:
 772         if (neigh_node)
 773                 batadv_neigh_node_free_ref(neigh_node);
 774         if (router)
 775                 batadv_neigh_node_free_ref(router);
 776 }
 777
 778 static int batadv_iv_ogm_calc_tq(struct orig_node *orig_node,
 779                                  struct orig_node *orig_neigh_node,
 780                                  struct batman_ogm_packet *batman_ogm_packet,
 781                                  struct hard_iface *if_incoming)
 782 {
 783         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 784         struct neigh_node *neigh_node = NULL, *tmp_neigh_node;
 785         struct hlist_node *node;
 786         uint8_t total_count;
 787         uint8_t orig_eq_count, neigh_rq_count, neigh_rq_inv, tq_own;
 788         unsigned int neigh_rq_inv_cube, neigh_rq_max_cube;
 789         int tq_asym_penalty, inv_asym_penalty, ret = 0;
 790         unsigned int combined_tq;
 791
 792         /* find corresponding one hop neighbor */
 793         rcu_read_lock();
 794         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 795                                  &orig_neigh_node->neigh_list, list) {
 796
 797                 if (!batadv_compare_eth(tmp_neigh_node->addr,
 798                                         orig_neigh_node->orig))
 799                         continue;
 800
 801                 if (tmp_neigh_node->if_incoming != if_incoming)
 802                         continue;
 803
 804                 if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
 805                         continue;
 806
 807                 neigh_node = tmp_neigh_node;
 808                 break;
 809         }
 810         rcu_read_unlock();
 811
 812         if (!neigh_node)
 813                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
 814                                                      orig_neigh_node->orig,
 815                                                      orig_neigh_node,
 816                                                      orig_neigh_node,
 817                                                      batman_ogm_packet->seqno);
 818
 819         if (!neigh_node)
 820                 goto out;
 821
 822         /* if orig_node is direct neighbor update neigh_node last_seen */
 823         if (orig_node == orig_neigh_node)
 824                 neigh_node->last_seen = jiffies;
 825
 826         orig_node->last_seen = jiffies;
 827
 828         /* find packet count of corresponding one hop neighbor */
 829         spin_lock_bh(&orig_node->ogm_cnt_lock);
 830         orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num];
 831         neigh_rq_count = neigh_node->real_packet_count;
 832         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 833
 834         /* pay attention to not get a value bigger than 100 % */
 835         total_count = (orig_eq_count > neigh_rq_count ?
 836                        neigh_rq_count : orig_eq_count);
 837
 838         /* if we have too few packets (too less data) we set tq_own to zero
 839          * if we receive too few packets it is not considered bidirectional
 840          */
 841         if (total_count < BATADV_TQ_LOCAL_BIDRECT_SEND_MINIMUM ||
 842             neigh_rq_count < BATADV_TQ_LOCAL_BIDRECT_RECV_MINIMUM)
 843                 tq_own = 0;
 844         else
 845                 /* neigh_node->real_packet_count is never zero as we
 846                  * only purge old information when getting new
 847                  * information
 848                  */
 849                 tq_own = (BATADV_TQ_MAX_VALUE * total_count) /  neigh_rq_count;
 850
 851         /* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
 852          * affect the nearly-symmetric links only a little, but
 853          * punishes asymmetric links more.  This will give a value
 854          * between 0 and TQ_MAX_VALUE
 855          */
 856         neigh_rq_inv = BATADV_TQ_LOCAL_WINDOW_SIZE - neigh_rq_count;
 857         neigh_rq_inv_cube = neigh_rq_inv * neigh_rq_inv * neigh_rq_inv;
 858         neigh_rq_max_cube = BATADV_TQ_LOCAL_WINDOW_SIZE *
 859                             BATADV_TQ_LOCAL_WINDOW_SIZE *
 860                             BATADV_TQ_LOCAL_WINDOW_SIZE;
 861         inv_asym_penalty = BATADV_TQ_MAX_VALUE * neigh_rq_inv_cube;
 862         inv_asym_penalty /= neigh_rq_max_cube;
 863         tq_asym_penalty = BATADV_TQ_MAX_VALUE - inv_asym_penalty;
 864
 865         combined_tq = batman_ogm_packet->tq * tq_own * tq_asym_penalty;
 866         combined_tq /= BATADV_TQ_MAX_VALUE * BATADV_TQ_MAX_VALUE;
 867         batman_ogm_packet->tq = combined_tq;
 868
 869         batadv_dbg(DBG_BATMAN, bat_priv,
 870                    "bidirectional: orig = %-15pM neigh = %-15pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, total tq: %3i\n",
 871                    orig_node->orig, orig_neigh_node->orig, total_count,
 872                    neigh_rq_count, tq_own,
 873                    tq_asym_penalty, batman_ogm_packet->tq);
 874
 875         /* if link has the minimum required transmission quality
 876          * consider it bidirectional
 877          */
 878         if (batman_ogm_packet->tq >= BATADV_TQ_TOTAL_BIDRECT_LIMIT)
 879                 ret = 1;
 880
 881 out:
 882         if (neigh_node)
 883                 batadv_neigh_node_free_ref(neigh_node);
 884         return ret;
 885 }
 886
 887 /* processes a batman packet for all interfaces, adjusts the sequence number and
 888  * finds out whether it is a duplicate.
 889  * returns:
 890  *   1 the packet is a duplicate
 891  *   0 the packet has not yet been received
 892  *  -1 the packet is old and has been received while the seqno window
 893  *     was protected. Caller should drop it.
 894  */
 895 static int
 896 batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
 897                             const struct batman_ogm_packet *batman_ogm_packet,
 898                             const struct hard_iface *if_incoming)
 899 {
 900         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 901         struct orig_node *orig_node;
 902         struct neigh_node *tmp_neigh_node;
 903         struct hlist_node *node;
 904         int is_duplicate = 0;
 905         int32_t seq_diff;
 906         int need_update = 0;
 907         int set_mark, ret = -1;
 908         uint32_t seqno = ntohl(batman_ogm_packet->seqno);
 909         uint8_t *neigh_addr;
 910
 911         orig_node = batadv_get_orig_node(bat_priv, batman_ogm_packet->orig);
 912         if (!orig_node)
 913                 return 0;
 914
 915         spin_lock_bh(&orig_node->ogm_cnt_lock);
 916         seq_diff = seqno - orig_node->last_real_seqno;
 917
 918         /* signalize caller that the packet is to be dropped. */
 919         if (!hlist_empty(&orig_node->neigh_list) &&
 920             batadv_window_protected(bat_priv, seq_diff,
 921                                     &orig_node->batman_seqno_reset))
 922                 goto out;
 923
 924         rcu_read_lock();
 925         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 926                                  &orig_node->neigh_list, list) {
 927
 928                 is_duplicate |= batadv_test_bit(tmp_neigh_node->real_bits,
 929                                                 orig_node->last_real_seqno,
 930                                                 seqno);
 931
 932                 neigh_addr = tmp_neigh_node->addr;
 933                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
 934                     tmp_neigh_node->if_incoming == if_incoming)
 935                         set_mark = 1;
 936                 else
 937                         set_mark = 0;
 938
 939                 /* if the window moved, set the update flag. */
 940                 need_update |= batadv_bit_get_packet(bat_priv,
 941                                                      tmp_neigh_node->real_bits,
 942                                                      seq_diff, set_mark);
 943
 944                 tmp_neigh_node->real_packet_count =
 945                         bitmap_weight(tmp_neigh_node->real_bits,
 946                                       BATADV_TQ_LOCAL_WINDOW_SIZE);
 947         }
 948         rcu_read_unlock();
 949
 950         if (need_update) {
 951                 batadv_dbg(DBG_BATMAN, bat_priv,
 952                            "updating last_seqno: old %u, new %u\n",
 953                            orig_node->last_real_seqno, seqno);
 954                 orig_node->last_real_seqno = seqno;
 955         }
 956
 957         ret = is_duplicate;
 958
 959 out:
 960         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 961         batadv_orig_node_free_ref(orig_node);
 962         return ret;
 963 }
 964
 965 static void batadv_iv_ogm_process(const struct ethhdr *ethhdr,
 966                                   struct batman_ogm_packet *batman_ogm_packet,
 967                                   const unsigned char *tt_buff,
 968                                   struct hard_iface *if_incoming)
 969 {
 970         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 971         struct hard_iface *hard_iface;
 972         struct orig_node *orig_neigh_node, *orig_node;
 973         struct neigh_node *router = NULL, *router_router = NULL;
 974         struct neigh_node *orig_neigh_router = NULL;
 975         int has_directlink_flag;
 976         int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
 977         int is_broadcast = 0, is_bidirect;
 978         bool is_single_hop_neigh = false;
 979         bool is_from_best_next_hop = false;
 980         int is_duplicate, sameseq, simlar_ttl;
 981         uint32_t if_incoming_seqno;
 982         uint8_t *prev_sender;
 983
 984         /* Silently drop when the batman packet is actually not a
 985          * correct packet.
 986          *
 987          * This might happen if a packet is padded (e.g. Ethernet has a
 988          * minimum frame length of 64 byte) and the aggregation interprets
 989          * it as an additional length.
 990          *
 991          * TODO: A more sane solution would be to have a bit in the
 992          * batman_ogm_packet to detect whether the packet is the last
 993          * packet in an aggregation.  Here we expect that the padding
 994          * is always zero (or not 0x01)
 995          */
 996         if (batman_ogm_packet->header.packet_type != BAT_IV_OGM)
 997                 return;
 998
 999         /* could be changed by schedule_own_packet() */
1000         if_incoming_seqno = atomic_read(&if_incoming->seqno);
1001
1002         has_directlink_flag = (batman_ogm_packet->flags & DIRECTLINK ? 1 : 0);
1003
1004         if (batadv_compare_eth(ethhdr->h_source, batman_ogm_packet->orig))
1005                 is_single_hop_neigh = true;
1006
1007         batadv_dbg(DBG_BATMAN, bat_priv,
1008                    "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",
1009                    ethhdr->h_source, if_incoming->net_dev->name,
1010                    if_incoming->net_dev->dev_addr, batman_ogm_packet->orig,
1011                    batman_ogm_packet->prev_sender,
1012                    ntohl(batman_ogm_packet->seqno), batman_ogm_packet->ttvn,
1013                    ntohs(batman_ogm_packet->tt_crc),
1014                    batman_ogm_packet->tt_num_changes, batman_ogm_packet->tq,
1015                    batman_ogm_packet->header.ttl,
1016                    batman_ogm_packet->header.version, has_directlink_flag);
1017
1018         rcu_read_lock();
1019         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
1020                 if (hard_iface->if_status != IF_ACTIVE)
1021                         continue;
1022
1023                 if (hard_iface->soft_iface != if_incoming->soft_iface)
1024                         continue;
1025
1026                 if (batadv_compare_eth(ethhdr->h_source,
1027                                        hard_iface->net_dev->dev_addr))
1028                         is_my_addr = 1;
1029
1030                 if (batadv_compare_eth(batman_ogm_packet->orig,
1031                                        hard_iface->net_dev->dev_addr))
1032                         is_my_orig = 1;
1033
1034                 if (batadv_compare_eth(batman_ogm_packet->prev_sender,
1035                                        hard_iface->net_dev->dev_addr))
1036                         is_my_oldorig = 1;
1037
1038                 if (is_broadcast_ether_addr(ethhdr->h_source))
1039                         is_broadcast = 1;
1040         }
1041         rcu_read_unlock();
1042
1043         if (batman_ogm_packet->header.version != BATADV_COMPAT_VERSION) {
1044                 batadv_dbg(DBG_BATMAN, bat_priv,
1045                            "Drop packet: incompatible batman version (%i)\n",
1046                            batman_ogm_packet->header.version);
1047                 return;
1048         }
1049
1050         if (is_my_addr) {
1051                 batadv_dbg(DBG_BATMAN, bat_priv,
1052                            "Drop packet: received my own broadcast (sender: %pM)\n",
1053                            ethhdr->h_source);
1054                 return;
1055         }
1056
1057         if (is_broadcast) {
1058                 batadv_dbg(DBG_BATMAN, bat_priv,
1059                            "Drop packet: ignoring all packets with broadcast source addr (sender: %pM)\n",
1060                            ethhdr->h_source);
1061                 return;
1062         }
1063
1064         if (is_my_orig) {
1065                 unsigned long *word;
1066                 int offset;
1067                 int32_t bit_pos;
1068                 int16_t if_num;
1069                 uint8_t *weight;
1070
1071                 orig_neigh_node = batadv_get_orig_node(bat_priv,
1072                                                        ethhdr->h_source);
1073                 if (!orig_neigh_node)
1074                         return;
1075
1076                 /* neighbor has to indicate direct link and it has to
1077                  * come via the corresponding interface
1078                  * save packet seqno for bidirectional check
1079                  */
1080                 if (has_directlink_flag &&
1081                     batadv_compare_eth(if_incoming->net_dev->dev_addr,
1082                                        batman_ogm_packet->orig)) {
1083                         if_num = if_incoming->if_num;
1084                         offset = if_num * BATADV_NUM_WORDS;
1085
1086                         spin_lock_bh(&orig_neigh_node->ogm_cnt_lock);
1087                         word = &(orig_neigh_node->bcast_own[offset]);
1088                         bit_pos = if_incoming_seqno - 2;
1089                         bit_pos -= ntohl(batman_ogm_packet->seqno);
1090                         batadv_set_bit(word, bit_pos);
1091                         weight = &orig_neigh_node->bcast_own_sum[if_num];
1092                         *weight = bitmap_weight(word,
1093                                                 BATADV_TQ_LOCAL_WINDOW_SIZE);
1094                         spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);
1095                 }
1096
1097                 batadv_dbg(DBG_BATMAN, bat_priv,
1098                            "Drop packet: originator packet from myself (via neighbor)\n");
1099                 batadv_orig_node_free_ref(orig_neigh_node);
1100                 return;
1101         }
1102
1103         if (is_my_oldorig) {
1104                 batadv_dbg(DBG_BATMAN, bat_priv,
1105                            "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
1106                            ethhdr->h_source);
1107                 return;
1108         }
1109
1110         if (batman_ogm_packet->flags & NOT_BEST_NEXT_HOP) {
1111                 batadv_dbg(DBG_BATMAN, bat_priv,
1112                            "Drop packet: ignoring all packets not forwarded from the best next hop (sender: %pM)\n",
1113                            ethhdr->h_source);
1114                 return;
1115         }
1116
1117         orig_node = batadv_get_orig_node(bat_priv, batman_ogm_packet->orig);
1118         if (!orig_node)
1119                 return;
1120
1121         is_duplicate = batadv_iv_ogm_update_seqnos(ethhdr, batman_ogm_packet,
1122                                                    if_incoming);
1123
1124         if (is_duplicate == -1) {
1125                 batadv_dbg(DBG_BATMAN, bat_priv,
1126                            "Drop packet: packet within seqno protection time (sender: %pM)\n",
1127                            ethhdr->h_source);
1128                 goto out;
1129         }
1130
1131         if (batman_ogm_packet->tq == 0) {
1132                 batadv_dbg(DBG_BATMAN, bat_priv,
1133                            "Drop packet: originator packet with tq equal 0\n");
1134                 goto out;
1135         }
1136
1137         router = batadv_orig_node_get_router(orig_node);
1138         if (router)
1139                 router_router = batadv_orig_node_get_router(router->orig_node);
1140
1141         if ((router && router->tq_avg != 0) &&
1142             (batadv_compare_eth(router->addr, ethhdr->h_source)))
1143                 is_from_best_next_hop = true;
1144
1145         prev_sender = batman_ogm_packet->prev_sender;
1146         /* avoid temporary routing loops */
1147         if (router && router_router &&
1148             (batadv_compare_eth(router->addr, prev_sender)) &&
1149             !(batadv_compare_eth(batman_ogm_packet->orig, prev_sender)) &&
1150             (batadv_compare_eth(router->addr, router_router->addr))) {
1151                 batadv_dbg(DBG_BATMAN, bat_priv,
1152                            "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
1153                            ethhdr->h_source);
1154                 goto out;
1155         }
1156
1157         /* if sender is a direct neighbor the sender mac equals
1158          * originator mac
1159          */
1160         orig_neigh_node = (is_single_hop_neigh ?
1161                            orig_node :
1162                            batadv_get_orig_node(bat_priv, ethhdr->h_source));
1163         if (!orig_neigh_node)
1164                 goto out;
1165
1166         orig_neigh_router = batadv_orig_node_get_router(orig_neigh_node);
1167
1168         /* drop packet if sender is not a direct neighbor and if we
1169          * don't route towards it
1170          */
1171         if (!is_single_hop_neigh && (!orig_neigh_router)) {
1172                 batadv_dbg(DBG_BATMAN, bat_priv,
1173                            "Drop packet: OGM via unknown neighbor!\n");
1174                 goto out_neigh;
1175         }
1176
1177         is_bidirect = batadv_iv_ogm_calc_tq(orig_node, orig_neigh_node,
1178                                             batman_ogm_packet, if_incoming);
1179
1180         batadv_bonding_save_primary(orig_node, orig_neigh_node,
1181                                     batman_ogm_packet);
1182
1183         /* update ranking if it is not a duplicate or has the same
1184          * seqno and similar ttl as the non-duplicate
1185          */
1186         sameseq = orig_node->last_real_seqno == ntohl(batman_ogm_packet->seqno);
1187         simlar_ttl = orig_node->last_ttl - 3 <= batman_ogm_packet->header.ttl;
1188         if (is_bidirect && (!is_duplicate || (sameseq && simlar_ttl)))
1189                 batadv_iv_ogm_orig_update(bat_priv, orig_node, ethhdr,
1190                                           batman_ogm_packet, if_incoming,
1191                                           tt_buff, is_duplicate);
1192
1193         /* is single hop (direct) neighbor */
1194         if (is_single_hop_neigh) {
1195
1196                 /* mark direct link on incoming interface */
1197                 batadv_iv_ogm_forward(orig_node, ethhdr, batman_ogm_packet,
1198                                       is_single_hop_neigh,
1199                                       is_from_best_next_hop, if_incoming);
1200
1201                 batadv_dbg(DBG_BATMAN, bat_priv,
1202                            "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
1203                 goto out_neigh;
1204         }
1205
1206         /* multihop originator */
1207         if (!is_bidirect) {
1208                 batadv_dbg(DBG_BATMAN, bat_priv,
1209                            "Drop packet: not received via bidirectional link\n");
1210                 goto out_neigh;
1211         }
1212
1213         if (is_duplicate) {
1214                 batadv_dbg(DBG_BATMAN, bat_priv,
1215                            "Drop packet: duplicate packet received\n");
1216                 goto out_neigh;
1217         }
1218
1219         batadv_dbg(DBG_BATMAN, bat_priv,
1220                    "Forwarding packet: rebroadcast originator packet\n");
1221         batadv_iv_ogm_forward(orig_node, ethhdr, batman_ogm_packet,
1222                               is_single_hop_neigh, is_from_best_next_hop,
1223                               if_incoming);
1224
1225 out_neigh:
1226         if ((orig_neigh_node) && (!is_single_hop_neigh))
1227                 batadv_orig_node_free_ref(orig_neigh_node);
1228 out:
1229         if (router)
1230                 batadv_neigh_node_free_ref(router);
1231         if (router_router)
1232                 batadv_neigh_node_free_ref(router_router);
1233         if (orig_neigh_router)
1234                 batadv_neigh_node_free_ref(orig_neigh_router);
1235
1236         batadv_orig_node_free_ref(orig_node);
1237 }
1238
1239 static int batadv_iv_ogm_receive(struct sk_buff *skb,
1240                                  struct hard_iface *if_incoming)
1241 {
1242         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1243         struct batman_ogm_packet *batman_ogm_packet;
1244         struct ethhdr *ethhdr;
1245         int buff_pos = 0, packet_len;
1246         unsigned char *tt_buff, *packet_buff;
1247         bool ret;
1248
1249         ret = batadv_check_management_packet(skb, if_incoming, BATADV_OGM_HLEN);
1250         if (!ret)
1251                 return NET_RX_DROP;
1252
1253         /* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
1254          * that does not have B.A.T.M.A.N. IV enabled ?
1255          */
1256         if (bat_priv->bat_algo_ops->bat_ogm_emit != batadv_iv_ogm_emit)
1257                 return NET_RX_DROP;
1258
1259         batadv_inc_counter(bat_priv, BAT_CNT_MGMT_RX);
1260         batadv_add_counter(bat_priv, BAT_CNT_MGMT_RX_BYTES,
1261                            skb->len + ETH_HLEN);
1262
1263         packet_len = skb_headlen(skb);
1264         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1265         packet_buff = skb->data;
1266         batman_ogm_packet = (struct batman_ogm_packet *)packet_buff;
1267
1268         /* unpack the aggregated packets and process them one by one */
1269         do {
1270                 tt_buff = packet_buff + buff_pos + BATADV_OGM_HLEN;
1271
1272                 batadv_iv_ogm_process(ethhdr, batman_ogm_packet, tt_buff,
1273                                       if_incoming);
1274
1275                 buff_pos += BATADV_OGM_HLEN;
1276                 buff_pos += batadv_tt_len(batman_ogm_packet->tt_num_changes);
1277
1278                 batman_ogm_packet = (struct batman_ogm_packet *)
1279                                                 (packet_buff + buff_pos);
1280         } while (batadv_iv_ogm_aggr_packet(buff_pos, packet_len,
1281                                            batman_ogm_packet->tt_num_changes));
1282
1283         kfree_skb(skb);
1284         return NET_RX_SUCCESS;
1285 }
1286
1287 static struct bat_algo_ops batadv_batman_iv __read_mostly = {
1288         .name = "BATMAN_IV",
1289         .bat_iface_enable = batadv_iv_ogm_iface_enable,
1290         .bat_iface_disable = batadv_iv_ogm_iface_disable,
1291         .bat_iface_update_mac = batadv_iv_ogm_iface_update_mac,
1292         .bat_primary_iface_set = batadv_iv_ogm_primary_iface_set,
1293         .bat_ogm_schedule = batadv_iv_ogm_schedule,
1294         .bat_ogm_emit = batadv_iv_ogm_emit,
1295 };
1296
1297 int __init batadv_iv_init(void)
1298 {
1299         int ret;
1300
1301         /* batman originator packet */
1302         ret = batadv_recv_handler_register(BAT_IV_OGM, batadv_iv_ogm_receive);
1303         if (ret < 0)
1304                 goto out;
1305
1306         ret = batadv_algo_register(&batadv_batman_iv);
1307         if (ret < 0)
1308                 goto handler_unregister;
1309
1310         goto out;
1311
1312 handler_unregister:
1313         batadv_recv_handler_unregister(BAT_IV_OGM);
1314 out:
1315         return ret;
1316 }