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 batadv_neigh_node *
  32 batadv_iv_ogm_neigh_new(struct batadv_hard_iface *hard_iface,
  33                         const uint8_t *neigh_addr,
  34                         struct batadv_orig_node *orig_node,
  35                         struct batadv_orig_node *orig_neigh, __be32 seqno)
  36 {
  37         struct batadv_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 batadv_hard_iface *hard_iface)
  58 {
  59         struct batadv_ogm_packet *batadv_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         batadv_ogm_packet = (struct batadv_ogm_packet *)hard_iface->packet_buff;
  74         batadv_ogm_packet->header.packet_type = BATADV_IV_OGM;
  75         batadv_ogm_packet->header.version = BATADV_COMPAT_VERSION;
  76         batadv_ogm_packet->header.ttl = 2;
  77         batadv_ogm_packet->flags = BATADV_NO_FLAGS;
  78         batadv_ogm_packet->tq = BATADV_TQ_MAX_VALUE;
  79         batadv_ogm_packet->tt_num_changes = 0;
  80         batadv_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 batadv_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 batadv_hard_iface *hard_iface)
  95 {
  96         struct batadv_ogm_packet *batadv_ogm_packet;
  97
  98         batadv_ogm_packet = (struct batadv_ogm_packet *)hard_iface->packet_buff;
  99         memcpy(batadv_ogm_packet->orig,
 100                hard_iface->net_dev->dev_addr, ETH_ALEN);
 101         memcpy(batadv_ogm_packet->prev_sender,
 102                hard_iface->net_dev->dev_addr, ETH_ALEN);
 103 }
 104
 105 static void
 106 batadv_iv_ogm_primary_iface_set(struct batadv_hard_iface *hard_iface)
 107 {
 108         struct batadv_ogm_packet *batadv_ogm_packet;
 109
 110         batadv_ogm_packet = (struct batadv_ogm_packet *)hard_iface->packet_buff;
 111         batadv_ogm_packet->flags = BATADV_PRIMARIES_FIRST_HOP;
 112         batadv_ogm_packet->header.ttl = BATADV_TTL;
 113 }
 114
 115 /* when do we schedule our own ogm to be sent */
 116 static unsigned long
 117 batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv)
 118 {
 119         unsigned int msecs;
 120
 121         msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
 122         msecs += (random32() % 2 * BATADV_JITTER);
 123
 124         return jiffies + msecs_to_jiffies(msecs);
 125 }
 126
 127 /* when do we schedule a ogm packet to be sent */
 128 static unsigned long batadv_iv_ogm_fwd_send_time(void)
 129 {
 130         return jiffies + msecs_to_jiffies(random32() % (BATADV_JITTER / 2));
 131 }
 132
 133 /* apply hop penalty for a normal link */
 134 static uint8_t batadv_hop_penalty(uint8_t tq,
 135                                   const struct batadv_priv *bat_priv)
 136 {
 137         int hop_penalty = atomic_read(&bat_priv->hop_penalty);
 138         int new_tq;
 139
 140         new_tq = tq * (BATADV_TQ_MAX_VALUE - hop_penalty);
 141         new_tq /= BATADV_TQ_MAX_VALUE;
 142
 143         return new_tq;
 144 }
 145
 146 /* is there another aggregated packet here? */
 147 static int batadv_iv_ogm_aggr_packet(int buff_pos, int packet_len,
 148                                      int tt_num_changes)
 149 {
 150         int next_buff_pos = 0;
 151
 152         next_buff_pos += buff_pos + BATADV_OGM_HLEN;
 153         next_buff_pos += batadv_tt_len(tt_num_changes);
 154
 155         return (next_buff_pos <= packet_len) &&
 156                (next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES);
 157 }
 158
 159 /* send a batman ogm to a given interface */
 160 static void batadv_iv_ogm_send_to_if(struct batadv_forw_packet *forw_packet,
 161                                      struct batadv_hard_iface *hard_iface)
 162 {
 163         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 164         char *fwd_str;
 165         uint8_t packet_num;
 166         int16_t buff_pos;
 167         struct batadv_ogm_packet *batadv_ogm_packet;
 168         struct sk_buff *skb;
 169         uint8_t *packet_pos;
 170
 171         if (hard_iface->if_status != BATADV_IF_ACTIVE)
 172                 return;
 173
 174         packet_num = 0;
 175         buff_pos = 0;
 176         packet_pos = forw_packet->skb->data;
 177         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 178
 179         /* adjust all flags and log packets */
 180         while (batadv_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
 181                                          batadv_ogm_packet->tt_num_changes)) {
 182
 183                 /* we might have aggregated direct link packets with an
 184                  * ordinary base packet
 185                  */
 186                 if (forw_packet->direct_link_flags & BIT(packet_num) &&
 187                     forw_packet->if_incoming == hard_iface)
 188                         batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 189                 else
 190                         batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 191
 192                 if (packet_num > 0 || !forw_packet->own)
 193                         fwd_str = "Forwarding";
 194                 else
 195                         fwd_str = "Sending own";
 196
 197                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 198                            "%s %spacket (originator %pM, seqno %u, TQ %d, TTL %d, IDF %s, ttvn %d) on interface %s [%pM]\n",
 199                            fwd_str, (packet_num > 0 ? "aggregated " : ""),
 200                            batadv_ogm_packet->orig,
 201                            ntohl(batadv_ogm_packet->seqno),
 202                            batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl,
 203                            (batadv_ogm_packet->flags & BATADV_DIRECTLINK ?
 204                             "on" : "off"),
 205                            batadv_ogm_packet->ttvn, hard_iface->net_dev->name,
 206                            hard_iface->net_dev->dev_addr);
 207
 208                 buff_pos += BATADV_OGM_HLEN;
 209                 buff_pos += batadv_tt_len(batadv_ogm_packet->tt_num_changes);
 210                 packet_num++;
 211                 packet_pos = forw_packet->skb->data + buff_pos;
 212                 batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 213         }
 214
 215         /* create clone because function is called more than once */
 216         skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
 217         if (skb) {
 218                 batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX);
 219                 batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES,
 220                                    skb->len + ETH_HLEN);
 221                 batadv_send_skb_packet(skb, hard_iface, batadv_broadcast_addr);
 222         }
 223 }
 224
 225 /* send a batman ogm packet */
 226 static void batadv_iv_ogm_emit(struct batadv_forw_packet *forw_packet)
 227 {
 228         struct batadv_hard_iface *hard_iface;
 229         struct net_device *soft_iface;
 230         struct batadv_priv *bat_priv;
 231         struct batadv_hard_iface *primary_if = NULL;
 232         struct batadv_ogm_packet *batadv_ogm_packet;
 233         unsigned char directlink;
 234         uint8_t *packet_pos;
 235
 236         packet_pos = forw_packet->skb->data;
 237         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 238         directlink = (batadv_ogm_packet->flags & BATADV_DIRECTLINK ? 1 : 0);
 239
 240         if (!forw_packet->if_incoming) {
 241                 pr_err("Error - can't forward packet: incoming iface not specified\n");
 242                 goto out;
 243         }
 244
 245         soft_iface = forw_packet->if_incoming->soft_iface;
 246         bat_priv = netdev_priv(soft_iface);
 247
 248         if (forw_packet->if_incoming->if_status != BATADV_IF_ACTIVE)
 249                 goto out;
 250
 251         primary_if = batadv_primary_if_get_selected(bat_priv);
 252         if (!primary_if)
 253                 goto out;
 254
 255         /* multihomed peer assumed
 256          * non-primary OGMs are only broadcasted on their interface
 257          */
 258         if ((directlink && (batadv_ogm_packet->header.ttl == 1)) ||
 259             (forw_packet->own && (forw_packet->if_incoming != primary_if))) {
 260
 261                 /* FIXME: what about aggregated packets ? */
 262                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 263                            "%s packet (originator %pM, seqno %u, TTL %d) on interface %s [%pM]\n",
 264                            (forw_packet->own ? "Sending own" : "Forwarding"),
 265                            batadv_ogm_packet->orig,
 266                            ntohl(batadv_ogm_packet->seqno),
 267                            batadv_ogm_packet->header.ttl,
 268                            forw_packet->if_incoming->net_dev->name,
 269                            forw_packet->if_incoming->net_dev->dev_addr);
 270
 271                 /* skb is only used once and than forw_packet is free'd */
 272                 batadv_send_skb_packet(forw_packet->skb,
 273                                        forw_packet->if_incoming,
 274                                        batadv_broadcast_addr);
 275                 forw_packet->skb = NULL;
 276
 277                 goto out;
 278         }
 279
 280         /* broadcast on every interface */
 281         rcu_read_lock();
 282         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 283                 if (hard_iface->soft_iface != soft_iface)
 284                         continue;
 285
 286                 batadv_iv_ogm_send_to_if(forw_packet, hard_iface);
 287         }
 288         rcu_read_unlock();
 289
 290 out:
 291         if (primary_if)
 292                 batadv_hardif_free_ref(primary_if);
 293 }
 294
 295 /* return true if new_packet can be aggregated with forw_packet */
 296 static bool
 297 batadv_iv_ogm_can_aggregate(const struct batadv_ogm_packet *new_bat_ogm_packet,
 298                             struct batadv_priv *bat_priv,
 299                             int packet_len, unsigned long send_time,
 300                             bool directlink,
 301                             const struct batadv_hard_iface *if_incoming,
 302                             const struct batadv_forw_packet *forw_packet)
 303 {
 304         struct batadv_ogm_packet *batadv_ogm_packet;
 305         int aggregated_bytes = forw_packet->packet_len + packet_len;
 306         struct batadv_hard_iface *primary_if = NULL;
 307         bool res = false;
 308         unsigned long aggregation_end_time;
 309
 310         batadv_ogm_packet = (struct batadv_ogm_packet *)forw_packet->skb->data;
 311         aggregation_end_time = send_time;
 312         aggregation_end_time += msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 313
 314         /* we can aggregate the current packet to this aggregated packet
 315          * if:
 316          *
 317          * - the send time is within our MAX_AGGREGATION_MS time
 318          * - the resulting packet wont be bigger than
 319          *   MAX_AGGREGATION_BYTES
 320          */
 321         if (time_before(send_time, forw_packet->send_time) &&
 322             time_after_eq(aggregation_end_time, forw_packet->send_time) &&
 323             (aggregated_bytes <= BATADV_MAX_AGGREGATION_BYTES)) {
 324
 325                 /* check aggregation compatibility
 326                  * -> direct link packets are broadcasted on
 327                  *    their interface only
 328                  * -> aggregate packet if the current packet is
 329                  *    a "global" packet as well as the base
 330                  *    packet
 331                  */
 332                 primary_if = batadv_primary_if_get_selected(bat_priv);
 333                 if (!primary_if)
 334                         goto out;
 335
 336                 /* packets without direct link flag and high TTL
 337                  * are flooded through the net
 338                  */
 339                 if ((!directlink) &&
 340                     (!(batadv_ogm_packet->flags & BATADV_DIRECTLINK)) &&
 341                     (batadv_ogm_packet->header.ttl != 1) &&
 342
 343                     /* own packets originating non-primary
 344                      * interfaces leave only that interface
 345                      */
 346                     ((!forw_packet->own) ||
 347                      (forw_packet->if_incoming == primary_if))) {
 348                         res = true;
 349                         goto out;
 350                 }
 351
 352                 /* if the incoming packet is sent via this one
 353                  * interface only - we still can aggregate
 354                  */
 355                 if ((directlink) &&
 356                     (new_bat_ogm_packet->header.ttl == 1) &&
 357                     (forw_packet->if_incoming == if_incoming) &&
 358
 359                     /* packets from direct neighbors or
 360                      * own secondary interface packets
 361                      * (= secondary interface packets in general)
 362                      */
 363                     (batadv_ogm_packet->flags & BATADV_DIRECTLINK ||
 364                      (forw_packet->own &&
 365                       forw_packet->if_incoming != primary_if))) {
 366                         res = true;
 367                         goto out;
 368                 }
 369         }
 370
 371 out:
 372         if (primary_if)
 373                 batadv_hardif_free_ref(primary_if);
 374         return res;
 375 }
 376
 377 /* create a new aggregated packet and add this packet to it */
 378 static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 379                                         int packet_len, unsigned long send_time,
 380                                         bool direct_link,
 381                                         struct batadv_hard_iface *if_incoming,
 382                                         int own_packet)
 383 {
 384         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 385         struct batadv_forw_packet *forw_packet_aggr;
 386         unsigned char *skb_buff;
 387         unsigned int skb_size;
 388
 389         if (!atomic_inc_not_zero(&if_incoming->refcount))
 390                 return;
 391
 392         /* own packet should always be scheduled */
 393         if (!own_packet) {
 394                 if (!batadv_atomic_dec_not_zero(&bat_priv->batman_queue_left)) {
 395                         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 396                                    "batman packet queue full\n");
 397                         goto out;
 398                 }
 399         }
 400
 401         forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC);
 402         if (!forw_packet_aggr) {
 403                 if (!own_packet)
 404                         atomic_inc(&bat_priv->batman_queue_left);
 405                 goto out;
 406         }
 407
 408         if ((atomic_read(&bat_priv->aggregated_ogms)) &&
 409             (packet_len < BATADV_MAX_AGGREGATION_BYTES))
 410                 skb_size = BATADV_MAX_AGGREGATION_BYTES + ETH_HLEN;
 411         else
 412                 skb_size = packet_len + ETH_HLEN;
 413
 414         forw_packet_aggr->skb = dev_alloc_skb(skb_size);
 415         if (!forw_packet_aggr->skb) {
 416                 if (!own_packet)
 417                         atomic_inc(&bat_priv->batman_queue_left);
 418                 kfree(forw_packet_aggr);
 419                 goto out;
 420         }
 421         skb_reserve(forw_packet_aggr->skb, ETH_HLEN);
 422
 423         INIT_HLIST_NODE(&forw_packet_aggr->list);
 424
 425         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 426         forw_packet_aggr->packet_len = packet_len;
 427         memcpy(skb_buff, packet_buff, packet_len);
 428
 429         forw_packet_aggr->own = own_packet;
 430         forw_packet_aggr->if_incoming = if_incoming;
 431         forw_packet_aggr->num_packets = 0;
 432         forw_packet_aggr->direct_link_flags = BATADV_NO_FLAGS;
 433         forw_packet_aggr->send_time = send_time;
 434
 435         /* save packet direct link flag status */
 436         if (direct_link)
 437                 forw_packet_aggr->direct_link_flags |= 1;
 438
 439         /* add new packet to packet list */
 440         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 441         hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
 442         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 443
 444         /* start timer for this packet */
 445         INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
 446                           batadv_send_outstanding_bat_ogm_packet);
 447         queue_delayed_work(batadv_event_workqueue,
 448                            &forw_packet_aggr->delayed_work,
 449                            send_time - jiffies);
 450
 451         return;
 452 out:
 453         batadv_hardif_free_ref(if_incoming);
 454 }
 455
 456 /* aggregate a new packet into the existing ogm packet */
 457 static void batadv_iv_ogm_aggregate(struct batadv_forw_packet *forw_packet_aggr,
 458                                     const unsigned char *packet_buff,
 459                                     int packet_len, bool direct_link)
 460 {
 461         unsigned char *skb_buff;
 462         unsigned long new_direct_link_flag;
 463
 464         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 465         memcpy(skb_buff, packet_buff, packet_len);
 466         forw_packet_aggr->packet_len += packet_len;
 467         forw_packet_aggr->num_packets++;
 468
 469         /* save packet direct link flag status */
 470         if (direct_link) {
 471                 new_direct_link_flag = BIT(forw_packet_aggr->num_packets);
 472                 forw_packet_aggr->direct_link_flags |= new_direct_link_flag;
 473         }
 474 }
 475
 476 static void batadv_iv_ogm_queue_add(struct batadv_priv *bat_priv,
 477                                     unsigned char *packet_buff,
 478                                     int packet_len,
 479                                     struct batadv_hard_iface *if_incoming,
 480                                     int own_packet, unsigned long send_time)
 481 {
 482         /* _aggr -> pointer to the packet we want to aggregate with
 483          * _pos -> pointer to the position in the queue
 484          */
 485         struct batadv_forw_packet *forw_packet_aggr = NULL;
 486         struct batadv_forw_packet *forw_packet_pos = NULL;
 487         struct hlist_node *tmp_node;
 488         struct batadv_ogm_packet *batadv_ogm_packet;
 489         bool direct_link;
 490         unsigned long max_aggregation_jiffies;
 491
 492         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
 493         direct_link = batadv_ogm_packet->flags & BATADV_DIRECTLINK ? 1 : 0;
 494         max_aggregation_jiffies = msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 495
 496         /* find position for the packet in the forward queue */
 497         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 498         /* own packets are not to be aggregated */
 499         if ((atomic_read(&bat_priv->aggregated_ogms)) && (!own_packet)) {
 500                 hlist_for_each_entry(forw_packet_pos, tmp_node,
 501                                      &bat_priv->forw_bat_list, list) {
 502                         if (batadv_iv_ogm_can_aggregate(batadv_ogm_packet,
 503                                                         bat_priv, packet_len,
 504                                                         send_time, direct_link,
 505                                                         if_incoming,
 506                                                         forw_packet_pos)) {
 507                                 forw_packet_aggr = forw_packet_pos;
 508                                 break;
 509                         }
 510                 }
 511         }
 512
 513         /* nothing to aggregate with - either aggregation disabled or no
 514          * suitable aggregation packet found
 515          */
 516         if (!forw_packet_aggr) {
 517                 /* the following section can run without the lock */
 518                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 519
 520                 /* if we could not aggregate this packet with one of the others
 521                  * we hold it back for a while, so that it might be aggregated
 522                  * later on
 523                  */
 524                 if (!own_packet && atomic_read(&bat_priv->aggregated_ogms))
 525                         send_time += max_aggregation_jiffies;
 526
 527                 batadv_iv_ogm_aggregate_new(packet_buff, packet_len,
 528                                             send_time, direct_link,
 529                                             if_incoming, own_packet);
 530         } else {
 531                 batadv_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
 532                                         packet_len, direct_link);
 533                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 534         }
 535 }
 536
 537 static void batadv_iv_ogm_forward(struct batadv_orig_node *orig_node,
 538                                   const struct ethhdr *ethhdr,
 539                                   struct batadv_ogm_packet *batadv_ogm_packet,
 540                                   bool is_single_hop_neigh,
 541                                   bool is_from_best_next_hop,
 542                                   struct batadv_hard_iface *if_incoming)
 543 {
 544         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 545         uint8_t tt_num_changes;
 546
 547         if (batadv_ogm_packet->header.ttl <= 1) {
 548                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n");
 549                 return;
 550         }
 551
 552         if (!is_from_best_next_hop) {
 553                 /* Mark the forwarded packet when it is not coming from our
 554                  * best next hop. We still need to forward the packet for our
 555                  * neighbor link quality detection to work in case the packet
 556                  * originated from a single hop neighbor. Otherwise we can
 557                  * simply drop the ogm.
 558                  */
 559                 if (is_single_hop_neigh)
 560                         batadv_ogm_packet->flags |= BATADV_NOT_BEST_NEXT_HOP;
 561                 else
 562                         return;
 563         }
 564
 565         tt_num_changes = batadv_ogm_packet->tt_num_changes;
 566
 567         batadv_ogm_packet->header.ttl--;
 568         memcpy(batadv_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
 569
 570         /* apply hop penalty */
 571         batadv_ogm_packet->tq = batadv_hop_penalty(batadv_ogm_packet->tq,
 572                                                    bat_priv);
 573
 574         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 575                    "Forwarding packet: tq: %i, ttl: %i\n",
 576                    batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl);
 577
 578         /* switch of primaries first hop flag when forwarding */
 579         batadv_ogm_packet->flags &= ~BATADV_PRIMARIES_FIRST_HOP;
 580         if (is_single_hop_neigh)
 581                 batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 582         else
 583                 batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 584
 585         batadv_iv_ogm_queue_add(bat_priv, (unsigned char *)batadv_ogm_packet,
 586                                 BATADV_OGM_HLEN + batadv_tt_len(tt_num_changes),
 587                                 if_incoming, 0, batadv_iv_ogm_fwd_send_time());
 588 }
 589
 590 static void batadv_iv_ogm_schedule(struct batadv_hard_iface *hard_iface)
 591 {
 592         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 593         struct batadv_ogm_packet *batadv_ogm_packet;
 594         struct batadv_hard_iface *primary_if;
 595         int vis_server, tt_num_changes = 0;
 596         uint32_t seqno;
 597         uint8_t bandwidth;
 598
 599         vis_server = atomic_read(&bat_priv->vis_mode);
 600         primary_if = batadv_primary_if_get_selected(bat_priv);
 601
 602         if (hard_iface == primary_if)
 603                 tt_num_changes = batadv_tt_append_diff(bat_priv,
 604                                                        &hard_iface->packet_buff,
 605                                                        &hard_iface->packet_len,
 606                                                        BATADV_OGM_HLEN);
 607
 608         batadv_ogm_packet = (struct batadv_ogm_packet *)hard_iface->packet_buff;
 609
 610         /* change sequence number to network order */
 611         seqno = (uint32_t)atomic_read(&hard_iface->seqno);
 612         batadv_ogm_packet->seqno = htonl(seqno);
 613         atomic_inc(&hard_iface->seqno);
 614
 615         batadv_ogm_packet->ttvn = atomic_read(&bat_priv->tt.vn);
 616         batadv_ogm_packet->tt_crc = htons(bat_priv->tt.local_crc);
 617         if (tt_num_changes >= 0)
 618                 batadv_ogm_packet->tt_num_changes = tt_num_changes;
 619
 620         if (vis_server == BATADV_VIS_TYPE_SERVER_SYNC)
 621                 batadv_ogm_packet->flags |= BATADV_VIS_SERVER;
 622         else
 623                 batadv_ogm_packet->flags &= ~BATADV_VIS_SERVER;
 624
 625         if (hard_iface == primary_if &&
 626             atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_SERVER) {
 627                 bandwidth = (uint8_t)atomic_read(&bat_priv->gw_bandwidth);
 628                 batadv_ogm_packet->gw_flags = bandwidth;
 629         } else {
 630                 batadv_ogm_packet->gw_flags = BATADV_NO_FLAGS;
 631         }
 632
 633         batadv_slide_own_bcast_window(hard_iface);
 634         batadv_iv_ogm_queue_add(bat_priv, hard_iface->packet_buff,
 635                                 hard_iface->packet_len, hard_iface, 1,
 636                                 batadv_iv_ogm_emit_send_time(bat_priv));
 637
 638         if (primary_if)
 639                 batadv_hardif_free_ref(primary_if);
 640 }
 641
 642 static void
 643 batadv_iv_ogm_orig_update(struct batadv_priv *bat_priv,
 644                           struct batadv_orig_node *orig_node,
 645                           const struct ethhdr *ethhdr,
 646                           const struct batadv_ogm_packet *batadv_ogm_packet,
 647                           struct batadv_hard_iface *if_incoming,
 648                           const unsigned char *tt_buff,
 649                           int is_duplicate)
 650 {
 651         struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 652         struct batadv_neigh_node *router = NULL;
 653         struct batadv_orig_node *orig_node_tmp;
 654         struct hlist_node *node;
 655         int if_num;
 656         uint8_t sum_orig, sum_neigh;
 657         uint8_t *neigh_addr;
 658         uint8_t tq_avg;
 659
 660         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 661                    "update_originator(): Searching and updating originator entry of received packet\n");
 662
 663         rcu_read_lock();
 664         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 665                                  &orig_node->neigh_list, list) {
 666                 neigh_addr = tmp_neigh_node->addr;
 667                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
 668                     tmp_neigh_node->if_incoming == if_incoming &&
 669                     atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
 670                         if (neigh_node)
 671                                 batadv_neigh_node_free_ref(neigh_node);
 672                         neigh_node = tmp_neigh_node;
 673                         continue;
 674                 }
 675
 676                 if (is_duplicate)
 677                         continue;
 678
 679                 spin_lock_bh(&tmp_neigh_node->lq_update_lock);
 680                 batadv_ring_buffer_set(tmp_neigh_node->tq_recv,
 681                                        &tmp_neigh_node->tq_index, 0);
 682                 tq_avg = batadv_ring_buffer_avg(tmp_neigh_node->tq_recv);
 683                 tmp_neigh_node->tq_avg = tq_avg;
 684                 spin_unlock_bh(&tmp_neigh_node->lq_update_lock);
 685         }
 686
 687         if (!neigh_node) {
 688                 struct batadv_orig_node *orig_tmp;
 689
 690                 orig_tmp = batadv_get_orig_node(bat_priv, ethhdr->h_source);
 691                 if (!orig_tmp)
 692                         goto unlock;
 693
 694                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
 695                                                      ethhdr->h_source,
 696                                                      orig_node, orig_tmp,
 697                                                      batadv_ogm_packet->seqno);
 698
 699                 batadv_orig_node_free_ref(orig_tmp);
 700                 if (!neigh_node)
 701                         goto unlock;
 702         } else
 703                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 704                            "Updating existing last-hop neighbor of originator\n");
 705
 706         rcu_read_unlock();
 707
 708         orig_node->flags = batadv_ogm_packet->flags;
 709         neigh_node->last_seen = jiffies;
 710
 711         spin_lock_bh(&neigh_node->lq_update_lock);
 712         batadv_ring_buffer_set(neigh_node->tq_recv,
 713                                &neigh_node->tq_index,
 714                                batadv_ogm_packet->tq);
 715         neigh_node->tq_avg = batadv_ring_buffer_avg(neigh_node->tq_recv);
 716         spin_unlock_bh(&neigh_node->lq_update_lock);
 717
 718         if (!is_duplicate) {
 719                 orig_node->last_ttl = batadv_ogm_packet->header.ttl;
 720                 neigh_node->last_ttl = batadv_ogm_packet->header.ttl;
 721         }
 722
 723         batadv_bonding_candidate_add(orig_node, neigh_node);
 724
 725         /* if this neighbor already is our next hop there is nothing
 726          * to change
 727          */
 728         router = batadv_orig_node_get_router(orig_node);
 729         if (router == neigh_node)
 730                 goto update_tt;
 731
 732         /* if this neighbor does not offer a better TQ we won't consider it */
 733         if (router && (router->tq_avg > neigh_node->tq_avg))
 734                 goto update_tt;
 735
 736         /* if the TQ is the same and the link not more symmetric we
 737          * won't consider it either
 738          */
 739         if (router && (neigh_node->tq_avg == router->tq_avg)) {
 740                 orig_node_tmp = router->orig_node;
 741                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 742                 if_num = router->if_incoming->if_num;
 743                 sum_orig = orig_node_tmp->bcast_own_sum[if_num];
 744                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 745
 746                 orig_node_tmp = neigh_node->orig_node;
 747                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 748                 if_num = neigh_node->if_incoming->if_num;
 749                 sum_neigh = orig_node_tmp->bcast_own_sum[if_num];
 750                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 751
 752                 if (sum_orig >= sum_neigh)
 753                         goto update_tt;
 754         }
 755
 756         batadv_update_route(bat_priv, orig_node, neigh_node);
 757
 758 update_tt:
 759         /* I have to check for transtable changes only if the OGM has been
 760          * sent through a primary interface
 761          */
 762         if (((batadv_ogm_packet->orig != ethhdr->h_source) &&
 763              (batadv_ogm_packet->header.ttl > 2)) ||
 764             (batadv_ogm_packet->flags & BATADV_PRIMARIES_FIRST_HOP))
 765                 batadv_tt_update_orig(bat_priv, orig_node, tt_buff,
 766                                       batadv_ogm_packet->tt_num_changes,
 767                                       batadv_ogm_packet->ttvn,
 768                                       ntohs(batadv_ogm_packet->tt_crc));
 769
 770         if (orig_node->gw_flags != batadv_ogm_packet->gw_flags)
 771                 batadv_gw_node_update(bat_priv, orig_node,
 772                                       batadv_ogm_packet->gw_flags);
 773
 774         orig_node->gw_flags = batadv_ogm_packet->gw_flags;
 775
 776         /* restart gateway selection if fast or late switching was enabled */
 777         if ((orig_node->gw_flags) &&
 778             (atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_CLIENT) &&
 779             (atomic_read(&bat_priv->gw_sel_class) > 2))
 780                 batadv_gw_check_election(bat_priv, orig_node);
 781
 782         goto out;
 783
 784 unlock:
 785         rcu_read_unlock();
 786 out:
 787         if (neigh_node)
 788                 batadv_neigh_node_free_ref(neigh_node);
 789         if (router)
 790                 batadv_neigh_node_free_ref(router);
 791 }
 792
 793 static int batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node,
 794                                  struct batadv_orig_node *orig_neigh_node,
 795                                  struct batadv_ogm_packet *batadv_ogm_packet,
 796                                  struct batadv_hard_iface *if_incoming)
 797 {
 798         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 799         struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node;
 800         struct hlist_node *node;
 801         uint8_t total_count;
 802         uint8_t orig_eq_count, neigh_rq_count, neigh_rq_inv, tq_own;
 803         unsigned int neigh_rq_inv_cube, neigh_rq_max_cube;
 804         int tq_asym_penalty, inv_asym_penalty, ret = 0;
 805         unsigned int combined_tq;
 806
 807         /* find corresponding one hop neighbor */
 808         rcu_read_lock();
 809         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 810                                  &orig_neigh_node->neigh_list, list) {
 811
 812                 if (!batadv_compare_eth(tmp_neigh_node->addr,
 813                                         orig_neigh_node->orig))
 814                         continue;
 815
 816                 if (tmp_neigh_node->if_incoming != if_incoming)
 817                         continue;
 818
 819                 if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
 820                         continue;
 821
 822                 neigh_node = tmp_neigh_node;
 823                 break;
 824         }
 825         rcu_read_unlock();
 826
 827         if (!neigh_node)
 828                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
 829                                                      orig_neigh_node->orig,
 830                                                      orig_neigh_node,
 831                                                      orig_neigh_node,
 832                                                      batadv_ogm_packet->seqno);
 833
 834         if (!neigh_node)
 835                 goto out;
 836
 837         /* if orig_node is direct neighbor update neigh_node last_seen */
 838         if (orig_node == orig_neigh_node)
 839                 neigh_node->last_seen = jiffies;
 840
 841         orig_node->last_seen = jiffies;
 842
 843         /* find packet count of corresponding one hop neighbor */
 844         spin_lock_bh(&orig_node->ogm_cnt_lock);
 845         orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num];
 846         neigh_rq_count = neigh_node->real_packet_count;
 847         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 848
 849         /* pay attention to not get a value bigger than 100 % */
 850         if (orig_eq_count > neigh_rq_count)
 851                 total_count = neigh_rq_count;
 852         else
 853                 total_count = orig_eq_count;
 854
 855         /* if we have too few packets (too less data) we set tq_own to zero
 856          * if we receive too few packets it is not considered bidirectional
 857          */
 858         if (total_count < BATADV_TQ_LOCAL_BIDRECT_SEND_MINIMUM ||
 859             neigh_rq_count < BATADV_TQ_LOCAL_BIDRECT_RECV_MINIMUM)
 860                 tq_own = 0;
 861         else
 862                 /* neigh_node->real_packet_count is never zero as we
 863                  * only purge old information when getting new
 864                  * information
 865                  */
 866                 tq_own = (BATADV_TQ_MAX_VALUE * total_count) /  neigh_rq_count;
 867
 868         /* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
 869          * affect the nearly-symmetric links only a little, but
 870          * punishes asymmetric links more.  This will give a value
 871          * between 0 and TQ_MAX_VALUE
 872          */
 873         neigh_rq_inv = BATADV_TQ_LOCAL_WINDOW_SIZE - neigh_rq_count;
 874         neigh_rq_inv_cube = neigh_rq_inv * neigh_rq_inv * neigh_rq_inv;
 875         neigh_rq_max_cube = BATADV_TQ_LOCAL_WINDOW_SIZE *
 876                             BATADV_TQ_LOCAL_WINDOW_SIZE *
 877                             BATADV_TQ_LOCAL_WINDOW_SIZE;
 878         inv_asym_penalty = BATADV_TQ_MAX_VALUE * neigh_rq_inv_cube;
 879         inv_asym_penalty /= neigh_rq_max_cube;
 880         tq_asym_penalty = BATADV_TQ_MAX_VALUE - inv_asym_penalty;
 881
 882         combined_tq = batadv_ogm_packet->tq * tq_own * tq_asym_penalty;
 883         combined_tq /= BATADV_TQ_MAX_VALUE * BATADV_TQ_MAX_VALUE;
 884         batadv_ogm_packet->tq = combined_tq;
 885
 886         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 887                    "bidirectional: orig = %-15pM neigh = %-15pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, total tq: %3i\n",
 888                    orig_node->orig, orig_neigh_node->orig, total_count,
 889                    neigh_rq_count, tq_own,
 890                    tq_asym_penalty, batadv_ogm_packet->tq);
 891
 892         /* if link has the minimum required transmission quality
 893          * consider it bidirectional
 894          */
 895         if (batadv_ogm_packet->tq >= BATADV_TQ_TOTAL_BIDRECT_LIMIT)
 896                 ret = 1;
 897
 898 out:
 899         if (neigh_node)
 900                 batadv_neigh_node_free_ref(neigh_node);
 901         return ret;
 902 }
 903
 904 /* processes a batman packet for all interfaces, adjusts the sequence number and
 905  * finds out whether it is a duplicate.
 906  * returns:
 907  *   1 the packet is a duplicate
 908  *   0 the packet has not yet been received
 909  *  -1 the packet is old and has been received while the seqno window
 910  *     was protected. Caller should drop it.
 911  */
 912 static int
 913 batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
 914                             const struct batadv_ogm_packet *batadv_ogm_packet,
 915                             const struct batadv_hard_iface *if_incoming)
 916 {
 917         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 918         struct batadv_orig_node *orig_node;
 919         struct batadv_neigh_node *tmp_neigh_node;
 920         struct hlist_node *node;
 921         int is_duplicate = 0;
 922         int32_t seq_diff;
 923         int need_update = 0;
 924         int set_mark, ret = -1;
 925         uint32_t seqno = ntohl(batadv_ogm_packet->seqno);
 926         uint8_t *neigh_addr;
 927         uint8_t packet_count;
 928
 929         orig_node = batadv_get_orig_node(bat_priv, batadv_ogm_packet->orig);
 930         if (!orig_node)
 931                 return 0;
 932
 933         spin_lock_bh(&orig_node->ogm_cnt_lock);
 934         seq_diff = seqno - orig_node->last_real_seqno;
 935
 936         /* signalize caller that the packet is to be dropped. */
 937         if (!hlist_empty(&orig_node->neigh_list) &&
 938             batadv_window_protected(bat_priv, seq_diff,
 939                                     &orig_node->batman_seqno_reset))
 940                 goto out;
 941
 942         rcu_read_lock();
 943         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 944                                  &orig_node->neigh_list, list) {
 945
 946                 is_duplicate |= batadv_test_bit(tmp_neigh_node->real_bits,
 947                                                 orig_node->last_real_seqno,
 948                                                 seqno);
 949
 950                 neigh_addr = tmp_neigh_node->addr;
 951                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
 952                     tmp_neigh_node->if_incoming == if_incoming)
 953                         set_mark = 1;
 954                 else
 955                         set_mark = 0;
 956
 957                 /* if the window moved, set the update flag. */
 958                 need_update |= batadv_bit_get_packet(bat_priv,
 959                                                      tmp_neigh_node->real_bits,
 960                                                      seq_diff, set_mark);
 961
 962                 packet_count = bitmap_weight(tmp_neigh_node->real_bits,
 963                                              BATADV_TQ_LOCAL_WINDOW_SIZE);
 964                 tmp_neigh_node->real_packet_count = packet_count;
 965         }
 966         rcu_read_unlock();
 967
 968         if (need_update) {
 969                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 970                            "updating last_seqno: old %u, new %u\n",
 971                            orig_node->last_real_seqno, seqno);
 972                 orig_node->last_real_seqno = seqno;
 973         }
 974
 975         ret = is_duplicate;
 976
 977 out:
 978         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 979         batadv_orig_node_free_ref(orig_node);
 980         return ret;
 981 }
 982
 983 static void batadv_iv_ogm_process(const struct ethhdr *ethhdr,
 984                                   struct batadv_ogm_packet *batadv_ogm_packet,
 985                                   const unsigned char *tt_buff,
 986                                   struct batadv_hard_iface *if_incoming)
 987 {
 988         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 989         struct batadv_hard_iface *hard_iface;
 990         struct batadv_orig_node *orig_neigh_node, *orig_node;
 991         struct batadv_neigh_node *router = NULL, *router_router = NULL;
 992         struct batadv_neigh_node *orig_neigh_router = NULL;
 993         int has_directlink_flag;
 994         int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
 995         int is_broadcast = 0, is_bidirect;
 996         bool is_single_hop_neigh = false;
 997         bool is_from_best_next_hop = false;
 998         int is_duplicate, sameseq, simlar_ttl;
 999         uint32_t if_incoming_seqno;
1000         uint8_t *prev_sender;
1001
1002         /* Silently drop when the batman packet is actually not a
1003          * correct packet.
1004          *
1005          * This might happen if a packet is padded (e.g. Ethernet has a
1006          * minimum frame length of 64 byte) and the aggregation interprets
1007          * it as an additional length.
1008          *
1009          * TODO: A more sane solution would be to have a bit in the
1010          * batadv_ogm_packet to detect whether the packet is the last
1011          * packet in an aggregation.  Here we expect that the padding
1012          * is always zero (or not 0x01)
1013          */
1014         if (batadv_ogm_packet->header.packet_type != BATADV_IV_OGM)
1015                 return;
1016
1017         /* could be changed by schedule_own_packet() */
1018         if_incoming_seqno = atomic_read(&if_incoming->seqno);
1019
1020         if (batadv_ogm_packet->flags & BATADV_DIRECTLINK)
1021                 has_directlink_flag = 1;
1022         else
1023                 has_directlink_flag = 0;
1024
1025         if (batadv_compare_eth(ethhdr->h_source, batadv_ogm_packet->orig))
1026                 is_single_hop_neigh = true;
1027
1028         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1029                    "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",
1030                    ethhdr->h_source, if_incoming->net_dev->name,
1031                    if_incoming->net_dev->dev_addr, batadv_ogm_packet->orig,
1032                    batadv_ogm_packet->prev_sender,
1033                    ntohl(batadv_ogm_packet->seqno), batadv_ogm_packet->ttvn,
1034                    ntohs(batadv_ogm_packet->tt_crc),
1035                    batadv_ogm_packet->tt_num_changes, batadv_ogm_packet->tq,
1036                    batadv_ogm_packet->header.ttl,
1037                    batadv_ogm_packet->header.version, has_directlink_flag);
1038
1039         rcu_read_lock();
1040         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
1041                 if (hard_iface->if_status != BATADV_IF_ACTIVE)
1042                         continue;
1043
1044                 if (hard_iface->soft_iface != if_incoming->soft_iface)
1045                         continue;
1046
1047                 if (batadv_compare_eth(ethhdr->h_source,
1048                                        hard_iface->net_dev->dev_addr))
1049                         is_my_addr = 1;
1050
1051                 if (batadv_compare_eth(batadv_ogm_packet->orig,
1052                                        hard_iface->net_dev->dev_addr))
1053                         is_my_orig = 1;
1054
1055                 if (batadv_compare_eth(batadv_ogm_packet->prev_sender,
1056                                        hard_iface->net_dev->dev_addr))
1057                         is_my_oldorig = 1;
1058
1059                 if (is_broadcast_ether_addr(ethhdr->h_source))
1060                         is_broadcast = 1;
1061         }
1062         rcu_read_unlock();
1063
1064         if (batadv_ogm_packet->header.version != BATADV_COMPAT_VERSION) {
1065                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1066                            "Drop packet: incompatible batman version (%i)\n",
1067                            batadv_ogm_packet->header.version);
1068                 return;
1069         }
1070
1071         if (is_my_addr) {
1072                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1073                            "Drop packet: received my own broadcast (sender: %pM)\n",
1074                            ethhdr->h_source);
1075                 return;
1076         }
1077
1078         if (is_broadcast) {
1079                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1080                            "Drop packet: ignoring all packets with broadcast source addr (sender: %pM)\n",
1081                            ethhdr->h_source);
1082                 return;
1083         }
1084
1085         if (is_my_orig) {
1086                 unsigned long *word;
1087                 int offset;
1088                 int32_t bit_pos;
1089                 int16_t if_num;
1090                 uint8_t *weight;
1091
1092                 orig_neigh_node = batadv_get_orig_node(bat_priv,
1093                                                        ethhdr->h_source);
1094                 if (!orig_neigh_node)
1095                         return;
1096
1097                 /* neighbor has to indicate direct link and it has to
1098                  * come via the corresponding interface
1099                  * save packet seqno for bidirectional check
1100                  */
1101                 if (has_directlink_flag &&
1102                     batadv_compare_eth(if_incoming->net_dev->dev_addr,
1103                                        batadv_ogm_packet->orig)) {
1104                         if_num = if_incoming->if_num;
1105                         offset = if_num * BATADV_NUM_WORDS;
1106
1107                         spin_lock_bh(&orig_neigh_node->ogm_cnt_lock);
1108                         word = &(orig_neigh_node->bcast_own[offset]);
1109                         bit_pos = if_incoming_seqno - 2;
1110                         bit_pos -= ntohl(batadv_ogm_packet->seqno);
1111                         batadv_set_bit(word, bit_pos);
1112                         weight = &orig_neigh_node->bcast_own_sum[if_num];
1113                         *weight = bitmap_weight(word,
1114                                                 BATADV_TQ_LOCAL_WINDOW_SIZE);
1115                         spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);
1116                 }
1117
1118                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1119                            "Drop packet: originator packet from myself (via neighbor)\n");
1120                 batadv_orig_node_free_ref(orig_neigh_node);
1121                 return;
1122         }
1123
1124         if (is_my_oldorig) {
1125                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1126                            "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
1127                            ethhdr->h_source);
1128                 return;
1129         }
1130
1131         if (batadv_ogm_packet->flags & BATADV_NOT_BEST_NEXT_HOP) {
1132                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1133                            "Drop packet: ignoring all packets not forwarded from the best next hop (sender: %pM)\n",
1134                            ethhdr->h_source);
1135                 return;
1136         }
1137
1138         orig_node = batadv_get_orig_node(bat_priv, batadv_ogm_packet->orig);
1139         if (!orig_node)
1140                 return;
1141
1142         is_duplicate = batadv_iv_ogm_update_seqnos(ethhdr, batadv_ogm_packet,
1143                                                    if_incoming);
1144
1145         if (is_duplicate == -1) {
1146                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1147                            "Drop packet: packet within seqno protection time (sender: %pM)\n",
1148                            ethhdr->h_source);
1149                 goto out;
1150         }
1151
1152         if (batadv_ogm_packet->tq == 0) {
1153                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1154                            "Drop packet: originator packet with tq equal 0\n");
1155                 goto out;
1156         }
1157
1158         router = batadv_orig_node_get_router(orig_node);
1159         if (router)
1160                 router_router = batadv_orig_node_get_router(router->orig_node);
1161
1162         if ((router && router->tq_avg != 0) &&
1163             (batadv_compare_eth(router->addr, ethhdr->h_source)))
1164                 is_from_best_next_hop = true;
1165
1166         prev_sender = batadv_ogm_packet->prev_sender;
1167         /* avoid temporary routing loops */
1168         if (router && router_router &&
1169             (batadv_compare_eth(router->addr, prev_sender)) &&
1170             !(batadv_compare_eth(batadv_ogm_packet->orig, prev_sender)) &&
1171             (batadv_compare_eth(router->addr, router_router->addr))) {
1172                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1173                            "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
1174                            ethhdr->h_source);
1175                 goto out;
1176         }
1177
1178         /* if sender is a direct neighbor the sender mac equals
1179          * originator mac
1180          */
1181         if (is_single_hop_neigh)
1182                 orig_neigh_node = orig_node;
1183         else
1184                 orig_neigh_node = batadv_get_orig_node(bat_priv,
1185                                                        ethhdr->h_source);
1186
1187         if (!orig_neigh_node)
1188                 goto out;
1189
1190         orig_neigh_router = batadv_orig_node_get_router(orig_neigh_node);
1191
1192         /* drop packet if sender is not a direct neighbor and if we
1193          * don't route towards it
1194          */
1195         if (!is_single_hop_neigh && (!orig_neigh_router)) {
1196                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1197                            "Drop packet: OGM via unknown neighbor!\n");
1198                 goto out_neigh;
1199         }
1200
1201         is_bidirect = batadv_iv_ogm_calc_tq(orig_node, orig_neigh_node,
1202                                             batadv_ogm_packet, if_incoming);
1203
1204         batadv_bonding_save_primary(orig_node, orig_neigh_node,
1205                                     batadv_ogm_packet);
1206
1207         /* update ranking if it is not a duplicate or has the same
1208          * seqno and similar ttl as the non-duplicate
1209          */
1210         sameseq = orig_node->last_real_seqno == ntohl(batadv_ogm_packet->seqno);
1211         simlar_ttl = orig_node->last_ttl - 3 <= batadv_ogm_packet->header.ttl;
1212         if (is_bidirect && (!is_duplicate || (sameseq && simlar_ttl)))
1213                 batadv_iv_ogm_orig_update(bat_priv, orig_node, ethhdr,
1214                                           batadv_ogm_packet, if_incoming,
1215                                           tt_buff, is_duplicate);
1216
1217         /* is single hop (direct) neighbor */
1218         if (is_single_hop_neigh) {
1219
1220                 /* mark direct link on incoming interface */
1221                 batadv_iv_ogm_forward(orig_node, ethhdr, batadv_ogm_packet,
1222                                       is_single_hop_neigh,
1223                                       is_from_best_next_hop, if_incoming);
1224
1225                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1226                            "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
1227                 goto out_neigh;
1228         }
1229
1230         /* multihop originator */
1231         if (!is_bidirect) {
1232                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1233                            "Drop packet: not received via bidirectional link\n");
1234                 goto out_neigh;
1235         }
1236
1237         if (is_duplicate) {
1238                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1239                            "Drop packet: duplicate packet received\n");
1240                 goto out_neigh;
1241         }
1242
1243         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1244                    "Forwarding packet: rebroadcast originator packet\n");
1245         batadv_iv_ogm_forward(orig_node, ethhdr, batadv_ogm_packet,
1246                               is_single_hop_neigh, is_from_best_next_hop,
1247                               if_incoming);
1248
1249 out_neigh:
1250         if ((orig_neigh_node) && (!is_single_hop_neigh))
1251                 batadv_orig_node_free_ref(orig_neigh_node);
1252 out:
1253         if (router)
1254                 batadv_neigh_node_free_ref(router);
1255         if (router_router)
1256                 batadv_neigh_node_free_ref(router_router);
1257         if (orig_neigh_router)
1258                 batadv_neigh_node_free_ref(orig_neigh_router);
1259
1260         batadv_orig_node_free_ref(orig_node);
1261 }
1262
1263 static int batadv_iv_ogm_receive(struct sk_buff *skb,
1264                                  struct batadv_hard_iface *if_incoming)
1265 {
1266         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1267         struct batadv_ogm_packet *batadv_ogm_packet;
1268         struct ethhdr *ethhdr;
1269         int buff_pos = 0, packet_len;
1270         unsigned char *tt_buff, *packet_buff;
1271         bool ret;
1272         uint8_t *packet_pos;
1273
1274         ret = batadv_check_management_packet(skb, if_incoming, BATADV_OGM_HLEN);
1275         if (!ret)
1276                 return NET_RX_DROP;
1277
1278         /* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
1279          * that does not have B.A.T.M.A.N. IV enabled ?
1280          */
1281         if (bat_priv->bat_algo_ops->bat_ogm_emit != batadv_iv_ogm_emit)
1282                 return NET_RX_DROP;
1283
1284         batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX);
1285         batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES,
1286                            skb->len + ETH_HLEN);
1287
1288         packet_len = skb_headlen(skb);
1289         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1290         packet_buff = skb->data;
1291         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
1292
1293         /* unpack the aggregated packets and process them one by one */
1294         do {
1295                 tt_buff = packet_buff + buff_pos + BATADV_OGM_HLEN;
1296
1297                 batadv_iv_ogm_process(ethhdr, batadv_ogm_packet, tt_buff,
1298                                       if_incoming);
1299
1300                 buff_pos += BATADV_OGM_HLEN;
1301                 buff_pos += batadv_tt_len(batadv_ogm_packet->tt_num_changes);
1302
1303                 packet_pos = packet_buff + buff_pos;
1304                 batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
1305         } while (batadv_iv_ogm_aggr_packet(buff_pos, packet_len,
1306                                            batadv_ogm_packet->tt_num_changes));
1307
1308         kfree_skb(skb);
1309         return NET_RX_SUCCESS;
1310 }
1311
1312 static struct batadv_algo_ops batadv_batman_iv __read_mostly = {
1313         .name = "BATMAN_IV",
1314         .bat_iface_enable = batadv_iv_ogm_iface_enable,
1315         .bat_iface_disable = batadv_iv_ogm_iface_disable,
1316         .bat_iface_update_mac = batadv_iv_ogm_iface_update_mac,
1317         .bat_primary_iface_set = batadv_iv_ogm_primary_iface_set,
1318         .bat_ogm_schedule = batadv_iv_ogm_schedule,
1319         .bat_ogm_emit = batadv_iv_ogm_emit,
1320 };
1321
1322 int __init batadv_iv_init(void)
1323 {
1324         int ret;
1325
1326         /* batman originator packet */
1327         ret = batadv_recv_handler_register(BATADV_IV_OGM,
1328                                            batadv_iv_ogm_receive);
1329         if (ret < 0)
1330                 goto out;
1331
1332         ret = batadv_algo_register(&batadv_batman_iv);
1333         if (ret < 0)
1334                 goto handler_unregister;
1335
1336         goto out;
1337
1338 handler_unregister:
1339         batadv_recv_handler_unregister(BATADV_IV_OGM);
1340 out:
1341         return ret;
1342 }