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