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