net/batman-adv/bat_iv_ogm.c

   1 /* Copyright (C) 2007-2013 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         unsigned char *ogm_buff;
  61         uint32_t random_seqno;
  62         int res = -ENOMEM;
  63
  64         /* randomize initial seqno to avoid collision */
  65         get_random_bytes(&random_seqno, sizeof(random_seqno));
  66         atomic_set(&hard_iface->bat_iv.ogm_seqno, random_seqno);
  67
  68         hard_iface->bat_iv.ogm_buff_len = BATADV_OGM_HLEN;
  69         ogm_buff = kmalloc(hard_iface->bat_iv.ogm_buff_len, GFP_ATOMIC);
  70         if (!ogm_buff)
  71                 goto out;
  72
  73         hard_iface->bat_iv.ogm_buff = ogm_buff;
  74
  75         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
  76         batadv_ogm_packet->header.packet_type = BATADV_IV_OGM;
  77         batadv_ogm_packet->header.version = BATADV_COMPAT_VERSION;
  78         batadv_ogm_packet->header.ttl = 2;
  79         batadv_ogm_packet->flags = BATADV_NO_FLAGS;
  80         batadv_ogm_packet->tq = BATADV_TQ_MAX_VALUE;
  81         batadv_ogm_packet->tt_num_changes = 0;
  82         batadv_ogm_packet->ttvn = 0;
  83
  84         res = 0;
  85
  86 out:
  87         return res;
  88 }
  89
  90 static void batadv_iv_ogm_iface_disable(struct batadv_hard_iface *hard_iface)
  91 {
  92         kfree(hard_iface->bat_iv.ogm_buff);
  93         hard_iface->bat_iv.ogm_buff = NULL;
  94 }
  95
  96 static void batadv_iv_ogm_iface_update_mac(struct batadv_hard_iface *hard_iface)
  97 {
  98         struct batadv_ogm_packet *batadv_ogm_packet;
  99         unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;
 100
 101         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 102         memcpy(batadv_ogm_packet->orig,
 103                hard_iface->net_dev->dev_addr, ETH_ALEN);
 104         memcpy(batadv_ogm_packet->prev_sender,
 105                hard_iface->net_dev->dev_addr, ETH_ALEN);
 106 }
 107
 108 static void
 109 batadv_iv_ogm_primary_iface_set(struct batadv_hard_iface *hard_iface)
 110 {
 111         struct batadv_ogm_packet *batadv_ogm_packet;
 112         unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;
 113
 114         batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 115         batadv_ogm_packet->flags = BATADV_PRIMARIES_FIRST_HOP;
 116         batadv_ogm_packet->header.ttl = BATADV_TTL;
 117 }
 118
 119 /* when do we schedule our own ogm to be sent */
 120 static unsigned long
 121 batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv)
 122 {
 123         unsigned int msecs;
 124
 125         msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER;
 126         msecs += prandom_u32() % (2 * BATADV_JITTER);
 127
 128         return jiffies + msecs_to_jiffies(msecs);
 129 }
 130
 131 /* when do we schedule a ogm packet to be sent */
 132 static unsigned long batadv_iv_ogm_fwd_send_time(void)
 133 {
 134         return jiffies + msecs_to_jiffies(prandom_u32() % (BATADV_JITTER / 2));
 135 }
 136
 137 /* apply hop penalty for a normal link */
 138 static uint8_t batadv_hop_penalty(uint8_t tq,
 139                                   const struct batadv_priv *bat_priv)
 140 {
 141         int hop_penalty = atomic_read(&bat_priv->hop_penalty);
 142         int new_tq;
 143
 144         new_tq = tq * (BATADV_TQ_MAX_VALUE - hop_penalty);
 145         new_tq /= BATADV_TQ_MAX_VALUE;
 146
 147         return new_tq;
 148 }
 149
 150 /* is there another aggregated packet here? */
 151 static int batadv_iv_ogm_aggr_packet(int buff_pos, int packet_len,
 152                                      int tt_num_changes)
 153 {
 154         int next_buff_pos = 0;
 155
 156         next_buff_pos += buff_pos + BATADV_OGM_HLEN;
 157         next_buff_pos += batadv_tt_len(tt_num_changes);
 158
 159         return (next_buff_pos <= packet_len) &&
 160                (next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES);
 161 }
 162
 163 /* send a batman ogm to a given interface */
 164 static void batadv_iv_ogm_send_to_if(struct batadv_forw_packet *forw_packet,
 165                                      struct batadv_hard_iface *hard_iface)
 166 {
 167         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 168         char *fwd_str;
 169         uint8_t packet_num;
 170         int16_t buff_pos;
 171         struct batadv_ogm_packet *batadv_ogm_packet;
 172         struct sk_buff *skb;
 173         uint8_t *packet_pos;
 174
 175         if (hard_iface->if_status != BATADV_IF_ACTIVE)
 176                 return;
 177
 178         packet_num = 0;
 179         buff_pos = 0;
 180         packet_pos = forw_packet->skb->data;
 181         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 182
 183         /* adjust all flags and log packets */
 184         while (batadv_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
 185                                          batadv_ogm_packet->tt_num_changes)) {
 186                 /* we might have aggregated direct link packets with an
 187                  * ordinary base packet
 188                  */
 189                 if (forw_packet->direct_link_flags & BIT(packet_num) &&
 190                     forw_packet->if_incoming == hard_iface)
 191                         batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 192                 else
 193                         batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 194
 195                 if (packet_num > 0 || !forw_packet->own)
 196                         fwd_str = "Forwarding";
 197                 else
 198                         fwd_str = "Sending own";
 199
 200                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 201                            "%s %spacket (originator %pM, seqno %u, TQ %d, TTL %d, IDF %s, ttvn %d) on interface %s [%pM]\n",
 202                            fwd_str, (packet_num > 0 ? "aggregated " : ""),
 203                            batadv_ogm_packet->orig,
 204                            ntohl(batadv_ogm_packet->seqno),
 205                            batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl,
 206                            (batadv_ogm_packet->flags & BATADV_DIRECTLINK ?
 207                             "on" : "off"),
 208                            batadv_ogm_packet->ttvn, hard_iface->net_dev->name,
 209                            hard_iface->net_dev->dev_addr);
 210
 211                 buff_pos += BATADV_OGM_HLEN;
 212                 buff_pos += batadv_tt_len(batadv_ogm_packet->tt_num_changes);
 213                 packet_num++;
 214                 packet_pos = forw_packet->skb->data + buff_pos;
 215                 batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 216         }
 217
 218         /* create clone because function is called more than once */
 219         skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
 220         if (skb) {
 221                 batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX);
 222                 batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES,
 223                                    skb->len + ETH_HLEN);
 224                 batadv_send_skb_packet(skb, hard_iface, batadv_broadcast_addr);
 225         }
 226 }
 227
 228 /* send a batman ogm packet */
 229 static void batadv_iv_ogm_emit(struct batadv_forw_packet *forw_packet)
 230 {
 231         struct batadv_hard_iface *hard_iface;
 232         struct net_device *soft_iface;
 233         struct batadv_priv *bat_priv;
 234         struct batadv_hard_iface *primary_if = NULL;
 235         struct batadv_ogm_packet *batadv_ogm_packet;
 236         unsigned char directlink;
 237         uint8_t *packet_pos;
 238
 239         packet_pos = forw_packet->skb->data;
 240         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
 241         directlink = (batadv_ogm_packet->flags & BATADV_DIRECTLINK ? 1 : 0);
 242
 243         if (!forw_packet->if_incoming) {
 244                 pr_err("Error - can't forward packet: incoming iface not specified\n");
 245                 goto out;
 246         }
 247
 248         soft_iface = forw_packet->if_incoming->soft_iface;
 249         bat_priv = netdev_priv(soft_iface);
 250
 251         if (forw_packet->if_incoming->if_status != BATADV_IF_ACTIVE)
 252                 goto out;
 253
 254         primary_if = batadv_primary_if_get_selected(bat_priv);
 255         if (!primary_if)
 256                 goto out;
 257
 258         /* multihomed peer assumed
 259          * non-primary OGMs are only broadcasted on their interface
 260          */
 261         if ((directlink && (batadv_ogm_packet->header.ttl == 1)) ||
 262             (forw_packet->own && (forw_packet->if_incoming != primary_if))) {
 263                 /* FIXME: what about aggregated packets ? */
 264                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 265                            "%s packet (originator %pM, seqno %u, TTL %d) on interface %s [%pM]\n",
 266                            (forw_packet->own ? "Sending own" : "Forwarding"),
 267                            batadv_ogm_packet->orig,
 268                            ntohl(batadv_ogm_packet->seqno),
 269                            batadv_ogm_packet->header.ttl,
 270                            forw_packet->if_incoming->net_dev->name,
 271                            forw_packet->if_incoming->net_dev->dev_addr);
 272
 273                 /* skb is only used once and than forw_packet is free'd */
 274                 batadv_send_skb_packet(forw_packet->skb,
 275                                        forw_packet->if_incoming,
 276                                        batadv_broadcast_addr);
 277                 forw_packet->skb = NULL;
 278
 279                 goto out;
 280         }
 281
 282         /* broadcast on every interface */
 283         rcu_read_lock();
 284         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 285                 if (hard_iface->soft_iface != soft_iface)
 286                         continue;
 287
 288                 batadv_iv_ogm_send_to_if(forw_packet, hard_iface);
 289         }
 290         rcu_read_unlock();
 291
 292 out:
 293         if (primary_if)
 294                 batadv_hardif_free_ref(primary_if);
 295 }
 296
 297 /* return true if new_packet can be aggregated with forw_packet */
 298 static bool
 299 batadv_iv_ogm_can_aggregate(const struct batadv_ogm_packet *new_bat_ogm_packet,
 300                             struct batadv_priv *bat_priv,
 301                             int packet_len, unsigned long send_time,
 302                             bool directlink,
 303                             const struct batadv_hard_iface *if_incoming,
 304                             const struct batadv_forw_packet *forw_packet)
 305 {
 306         struct batadv_ogm_packet *batadv_ogm_packet;
 307         int aggregated_bytes = forw_packet->packet_len + packet_len;
 308         struct batadv_hard_iface *primary_if = NULL;
 309         bool res = false;
 310         unsigned long aggregation_end_time;
 311
 312         batadv_ogm_packet = (struct batadv_ogm_packet *)forw_packet->skb->data;
 313         aggregation_end_time = send_time;
 314         aggregation_end_time += msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 315
 316         /* we can aggregate the current packet to this aggregated packet
 317          * if:
 318          *
 319          * - the send time is within our MAX_AGGREGATION_MS time
 320          * - the resulting packet wont be bigger than
 321          *   MAX_AGGREGATION_BYTES
 322          */
 323         if (time_before(send_time, forw_packet->send_time) &&
 324             time_after_eq(aggregation_end_time, forw_packet->send_time) &&
 325             (aggregated_bytes <= BATADV_MAX_AGGREGATION_BYTES)) {
 326                 /* check aggregation compatibility
 327                  * -> direct link packets are broadcasted on
 328                  *    their interface only
 329                  * -> aggregate packet if the current packet is
 330                  *    a "global" packet as well as the base
 331                  *    packet
 332                  */
 333                 primary_if = batadv_primary_if_get_selected(bat_priv);
 334                 if (!primary_if)
 335                         goto out;
 336
 337                 /* packets without direct link flag and high TTL
 338                  * are flooded through the net
 339                  */
 340                 if ((!directlink) &&
 341                     (!(batadv_ogm_packet->flags & BATADV_DIRECTLINK)) &&
 342                     (batadv_ogm_packet->header.ttl != 1) &&
 343
 344                     /* own packets originating non-primary
 345                      * interfaces leave only that interface
 346                      */
 347                     ((!forw_packet->own) ||
 348                      (forw_packet->if_incoming == primary_if))) {
 349                         res = true;
 350                         goto out;
 351                 }
 352
 353                 /* if the incoming packet is sent via this one
 354                  * interface only - we still can aggregate
 355                  */
 356                 if ((directlink) &&
 357                     (new_bat_ogm_packet->header.ttl == 1) &&
 358                     (forw_packet->if_incoming == if_incoming) &&
 359
 360                     /* packets from direct neighbors or
 361                      * own secondary interface packets
 362                      * (= secondary interface packets in general)
 363                      */
 364                     (batadv_ogm_packet->flags & BATADV_DIRECTLINK ||
 365                      (forw_packet->own &&
 366                       forw_packet->if_incoming != primary_if))) {
 367                         res = true;
 368                         goto out;
 369                 }
 370         }
 371
 372 out:
 373         if (primary_if)
 374                 batadv_hardif_free_ref(primary_if);
 375         return res;
 376 }
 377
 378 /* create a new aggregated packet and add this packet to it */
 379 static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 380                                         int packet_len, unsigned long send_time,
 381                                         bool direct_link,
 382                                         struct batadv_hard_iface *if_incoming,
 383                                         int own_packet)
 384 {
 385         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 386         struct batadv_forw_packet *forw_packet_aggr;
 387         unsigned char *skb_buff;
 388         unsigned int skb_size;
 389
 390         if (!atomic_inc_not_zero(&if_incoming->refcount))
 391                 return;
 392
 393         /* own packet should always be scheduled */
 394         if (!own_packet) {
 395                 if (!batadv_atomic_dec_not_zero(&bat_priv->batman_queue_left)) {
 396                         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 397                                    "batman packet queue full\n");
 398                         goto out;
 399                 }
 400         }
 401
 402         forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC);
 403         if (!forw_packet_aggr) {
 404                 if (!own_packet)
 405                         atomic_inc(&bat_priv->batman_queue_left);
 406                 goto out;
 407         }
 408
 409         if ((atomic_read(&bat_priv->aggregated_ogms)) &&
 410             (packet_len < BATADV_MAX_AGGREGATION_BYTES))
 411                 skb_size = BATADV_MAX_AGGREGATION_BYTES;
 412         else
 413                 skb_size = packet_len;
 414
 415         skb_size += ETH_HLEN + NET_IP_ALIGN;
 416
 417         forw_packet_aggr->skb = dev_alloc_skb(skb_size);
 418         if (!forw_packet_aggr->skb) {
 419                 if (!own_packet)
 420                         atomic_inc(&bat_priv->batman_queue_left);
 421                 kfree(forw_packet_aggr);
 422                 goto out;
 423         }
 424         skb_reserve(forw_packet_aggr->skb, ETH_HLEN + NET_IP_ALIGN);
 425
 426         INIT_HLIST_NODE(&forw_packet_aggr->list);
 427
 428         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 429         forw_packet_aggr->packet_len = packet_len;
 430         memcpy(skb_buff, packet_buff, packet_len);
 431
 432         forw_packet_aggr->own = own_packet;
 433         forw_packet_aggr->if_incoming = if_incoming;
 434         forw_packet_aggr->num_packets = 0;
 435         forw_packet_aggr->direct_link_flags = BATADV_NO_FLAGS;
 436         forw_packet_aggr->send_time = send_time;
 437
 438         /* save packet direct link flag status */
 439         if (direct_link)
 440                 forw_packet_aggr->direct_link_flags |= 1;
 441
 442         /* add new packet to packet list */
 443         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 444         hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
 445         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 446
 447         /* start timer for this packet */
 448         INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
 449                           batadv_send_outstanding_bat_ogm_packet);
 450         queue_delayed_work(batadv_event_workqueue,
 451                            &forw_packet_aggr->delayed_work,
 452                            send_time - jiffies);
 453
 454         return;
 455 out:
 456         batadv_hardif_free_ref(if_incoming);
 457 }
 458
 459 /* aggregate a new packet into the existing ogm packet */
 460 static void batadv_iv_ogm_aggregate(struct batadv_forw_packet *forw_packet_aggr,
 461                                     const unsigned char *packet_buff,
 462                                     int packet_len, bool direct_link)
 463 {
 464         unsigned char *skb_buff;
 465         unsigned long new_direct_link_flag;
 466
 467         skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
 468         memcpy(skb_buff, packet_buff, packet_len);
 469         forw_packet_aggr->packet_len += packet_len;
 470         forw_packet_aggr->num_packets++;
 471
 472         /* save packet direct link flag status */
 473         if (direct_link) {
 474                 new_direct_link_flag = BIT(forw_packet_aggr->num_packets);
 475                 forw_packet_aggr->direct_link_flags |= new_direct_link_flag;
 476         }
 477 }
 478
 479 static void batadv_iv_ogm_queue_add(struct batadv_priv *bat_priv,
 480                                     unsigned char *packet_buff,
 481                                     int packet_len,
 482                                     struct batadv_hard_iface *if_incoming,
 483                                     int own_packet, unsigned long send_time)
 484 {
 485         /* _aggr -> pointer to the packet we want to aggregate with
 486          * _pos -> pointer to the position in the queue
 487          */
 488         struct batadv_forw_packet *forw_packet_aggr = NULL;
 489         struct batadv_forw_packet *forw_packet_pos = NULL;
 490         struct hlist_node *tmp_node;
 491         struct batadv_ogm_packet *batadv_ogm_packet;
 492         bool direct_link;
 493         unsigned long max_aggregation_jiffies;
 494
 495         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
 496         direct_link = batadv_ogm_packet->flags & BATADV_DIRECTLINK ? 1 : 0;
 497         max_aggregation_jiffies = msecs_to_jiffies(BATADV_MAX_AGGREGATION_MS);
 498
 499         /* find position for the packet in the forward queue */
 500         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 501         /* own packets are not to be aggregated */
 502         if ((atomic_read(&bat_priv->aggregated_ogms)) && (!own_packet)) {
 503                 hlist_for_each_entry(forw_packet_pos, tmp_node,
 504                                      &bat_priv->forw_bat_list, list) {
 505                         if (batadv_iv_ogm_can_aggregate(batadv_ogm_packet,
 506                                                         bat_priv, packet_len,
 507                                                         send_time, direct_link,
 508                                                         if_incoming,
 509                                                         forw_packet_pos)) {
 510                                 forw_packet_aggr = forw_packet_pos;
 511                                 break;
 512                         }
 513                 }
 514         }
 515
 516         /* nothing to aggregate with - either aggregation disabled or no
 517          * suitable aggregation packet found
 518          */
 519         if (!forw_packet_aggr) {
 520                 /* the following section can run without the lock */
 521                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 522
 523                 /* if we could not aggregate this packet with one of the others
 524                  * we hold it back for a while, so that it might be aggregated
 525                  * later on
 526                  */
 527                 if (!own_packet && atomic_read(&bat_priv->aggregated_ogms))
 528                         send_time += max_aggregation_jiffies;
 529
 530                 batadv_iv_ogm_aggregate_new(packet_buff, packet_len,
 531                                             send_time, direct_link,
 532                                             if_incoming, own_packet);
 533         } else {
 534                 batadv_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
 535                                         packet_len, direct_link);
 536                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 537         }
 538 }
 539
 540 static void batadv_iv_ogm_forward(struct batadv_orig_node *orig_node,
 541                                   const struct ethhdr *ethhdr,
 542                                   struct batadv_ogm_packet *batadv_ogm_packet,
 543                                   bool is_single_hop_neigh,
 544                                   bool is_from_best_next_hop,
 545                                   struct batadv_hard_iface *if_incoming)
 546 {
 547         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 548         uint8_t tt_num_changes;
 549
 550         if (batadv_ogm_packet->header.ttl <= 1) {
 551                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n");
 552                 return;
 553         }
 554
 555         if (!is_from_best_next_hop) {
 556                 /* Mark the forwarded packet when it is not coming from our
 557                  * best next hop. We still need to forward the packet for our
 558                  * neighbor link quality detection to work in case the packet
 559                  * originated from a single hop neighbor. Otherwise we can
 560                  * simply drop the ogm.
 561                  */
 562                 if (is_single_hop_neigh)
 563                         batadv_ogm_packet->flags |= BATADV_NOT_BEST_NEXT_HOP;
 564                 else
 565                         return;
 566         }
 567
 568         tt_num_changes = batadv_ogm_packet->tt_num_changes;
 569
 570         batadv_ogm_packet->header.ttl--;
 571         memcpy(batadv_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
 572
 573         /* apply hop penalty */
 574         batadv_ogm_packet->tq = batadv_hop_penalty(batadv_ogm_packet->tq,
 575                                                    bat_priv);
 576
 577         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 578                    "Forwarding packet: tq: %i, ttl: %i\n",
 579                    batadv_ogm_packet->tq, batadv_ogm_packet->header.ttl);
 580
 581         /* switch of primaries first hop flag when forwarding */
 582         batadv_ogm_packet->flags &= ~BATADV_PRIMARIES_FIRST_HOP;
 583         if (is_single_hop_neigh)
 584                 batadv_ogm_packet->flags |= BATADV_DIRECTLINK;
 585         else
 586                 batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
 587
 588         batadv_iv_ogm_queue_add(bat_priv, (unsigned char *)batadv_ogm_packet,
 589                                 BATADV_OGM_HLEN + batadv_tt_len(tt_num_changes),
 590                                 if_incoming, 0, batadv_iv_ogm_fwd_send_time());
 591 }
 592
 593 static void batadv_iv_ogm_schedule(struct batadv_hard_iface *hard_iface)
 594 {
 595         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 596         unsigned char **ogm_buff = &hard_iface->bat_iv.ogm_buff;
 597         struct batadv_ogm_packet *batadv_ogm_packet;
 598         struct batadv_hard_iface *primary_if;
 599         int *ogm_buff_len = &hard_iface->bat_iv.ogm_buff_len;
 600         int vis_server, tt_num_changes = 0;
 601         uint32_t seqno;
 602         uint8_t bandwidth;
 603
 604         vis_server = atomic_read(&bat_priv->vis_mode);
 605         primary_if = batadv_primary_if_get_selected(bat_priv);
 606
 607         if (hard_iface == primary_if)
 608                 tt_num_changes = batadv_tt_append_diff(bat_priv, ogm_buff,
 609                                                        ogm_buff_len,
 610                                                        BATADV_OGM_HLEN);
 611
 612         batadv_ogm_packet = (struct batadv_ogm_packet *)(*ogm_buff);
 613
 614         /* change sequence number to network order */
 615         seqno = (uint32_t)atomic_read(&hard_iface->bat_iv.ogm_seqno);
 616         batadv_ogm_packet->seqno = htonl(seqno);
 617         atomic_inc(&hard_iface->bat_iv.ogm_seqno);
 618
 619         batadv_ogm_packet->ttvn = atomic_read(&bat_priv->tt.vn);
 620         batadv_ogm_packet->tt_crc = htons(bat_priv->tt.local_crc);
 621         if (tt_num_changes >= 0)
 622                 batadv_ogm_packet->tt_num_changes = tt_num_changes;
 623
 624         if (vis_server == BATADV_VIS_TYPE_SERVER_SYNC)
 625                 batadv_ogm_packet->flags |= BATADV_VIS_SERVER;
 626         else
 627                 batadv_ogm_packet->flags &= ~BATADV_VIS_SERVER;
 628
 629         if (hard_iface == primary_if &&
 630             atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_SERVER) {
 631                 bandwidth = (uint8_t)atomic_read(&bat_priv->gw_bandwidth);
 632                 batadv_ogm_packet->gw_flags = bandwidth;
 633         } else {
 634                 batadv_ogm_packet->gw_flags = BATADV_NO_FLAGS;
 635         }
 636
 637         batadv_slide_own_bcast_window(hard_iface);
 638         batadv_iv_ogm_queue_add(bat_priv, hard_iface->bat_iv.ogm_buff,
 639                                 hard_iface->bat_iv.ogm_buff_len, hard_iface, 1,
 640                                 batadv_iv_ogm_emit_send_time(bat_priv));
 641
 642         if (primary_if)
 643                 batadv_hardif_free_ref(primary_if);
 644 }
 645
 646 static void
 647 batadv_iv_ogm_orig_update(struct batadv_priv *bat_priv,
 648                           struct batadv_orig_node *orig_node,
 649                           const struct ethhdr *ethhdr,
 650                           const struct batadv_ogm_packet *batadv_ogm_packet,
 651                           struct batadv_hard_iface *if_incoming,
 652                           const unsigned char *tt_buff,
 653                           int is_duplicate)
 654 {
 655         struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 656         struct batadv_neigh_node *router = NULL;
 657         struct batadv_orig_node *orig_node_tmp;
 658         struct hlist_node *node;
 659         int if_num;
 660         uint8_t sum_orig, sum_neigh;
 661         uint8_t *neigh_addr;
 662         uint8_t tq_avg;
 663
 664         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 665                    "update_originator(): Searching and updating originator entry of received packet\n");
 666
 667         rcu_read_lock();
 668         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 669                                  &orig_node->neigh_list, list) {
 670                 neigh_addr = tmp_neigh_node->addr;
 671                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
 672                     tmp_neigh_node->if_incoming == if_incoming &&
 673                     atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
 674                         if (neigh_node)
 675                                 batadv_neigh_node_free_ref(neigh_node);
 676                         neigh_node = tmp_neigh_node;
 677                         continue;
 678                 }
 679
 680                 if (is_duplicate)
 681                         continue;
 682
 683                 spin_lock_bh(&tmp_neigh_node->lq_update_lock);
 684                 batadv_ring_buffer_set(tmp_neigh_node->tq_recv,
 685                                        &tmp_neigh_node->tq_index, 0);
 686                 tq_avg = batadv_ring_buffer_avg(tmp_neigh_node->tq_recv);
 687                 tmp_neigh_node->tq_avg = tq_avg;
 688                 spin_unlock_bh(&tmp_neigh_node->lq_update_lock);
 689         }
 690
 691         if (!neigh_node) {
 692                 struct batadv_orig_node *orig_tmp;
 693
 694                 orig_tmp = batadv_get_orig_node(bat_priv, ethhdr->h_source);
 695                 if (!orig_tmp)
 696                         goto unlock;
 697
 698                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
 699                                                      ethhdr->h_source,
 700                                                      orig_node, orig_tmp,
 701                                                      batadv_ogm_packet->seqno);
 702
 703                 batadv_orig_node_free_ref(orig_tmp);
 704                 if (!neigh_node)
 705                         goto unlock;
 706         } else
 707                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 708                            "Updating existing last-hop neighbor of originator\n");
 709
 710         rcu_read_unlock();
 711
 712         orig_node->flags = batadv_ogm_packet->flags;
 713         neigh_node->last_seen = jiffies;
 714
 715         spin_lock_bh(&neigh_node->lq_update_lock);
 716         batadv_ring_buffer_set(neigh_node->tq_recv,
 717                                &neigh_node->tq_index,
 718                                batadv_ogm_packet->tq);
 719         neigh_node->tq_avg = batadv_ring_buffer_avg(neigh_node->tq_recv);
 720         spin_unlock_bh(&neigh_node->lq_update_lock);
 721
 722         if (!is_duplicate) {
 723                 orig_node->last_ttl = batadv_ogm_packet->header.ttl;
 724                 neigh_node->last_ttl = batadv_ogm_packet->header.ttl;
 725         }
 726
 727         batadv_bonding_candidate_add(orig_node, neigh_node);
 728
 729         /* if this neighbor already is our next hop there is nothing
 730          * to change
 731          */
 732         router = batadv_orig_node_get_router(orig_node);
 733         if (router == neigh_node)
 734                 goto update_tt;
 735
 736         /* if this neighbor does not offer a better TQ we won't consider it */
 737         if (router && (router->tq_avg > neigh_node->tq_avg))
 738                 goto update_tt;
 739
 740         /* if the TQ is the same and the link not more symmetric we
 741          * won't consider it either
 742          */
 743         if (router && (neigh_node->tq_avg == router->tq_avg)) {
 744                 orig_node_tmp = router->orig_node;
 745                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 746                 if_num = router->if_incoming->if_num;
 747                 sum_orig = orig_node_tmp->bcast_own_sum[if_num];
 748                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 749
 750                 orig_node_tmp = neigh_node->orig_node;
 751                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 752                 if_num = neigh_node->if_incoming->if_num;
 753                 sum_neigh = orig_node_tmp->bcast_own_sum[if_num];
 754                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 755
 756                 if (sum_orig >= sum_neigh)
 757                         goto update_tt;
 758         }
 759
 760         batadv_update_route(bat_priv, orig_node, neigh_node);
 761
 762 update_tt:
 763         /* I have to check for transtable changes only if the OGM has been
 764          * sent through a primary interface
 765          */
 766         if (((batadv_ogm_packet->orig != ethhdr->h_source) &&
 767              (batadv_ogm_packet->header.ttl > 2)) ||
 768             (batadv_ogm_packet->flags & BATADV_PRIMARIES_FIRST_HOP))
 769                 batadv_tt_update_orig(bat_priv, orig_node, tt_buff,
 770                                       batadv_ogm_packet->tt_num_changes,
 771                                       batadv_ogm_packet->ttvn,
 772                                       ntohs(batadv_ogm_packet->tt_crc));
 773
 774         if (orig_node->gw_flags != batadv_ogm_packet->gw_flags)
 775                 batadv_gw_node_update(bat_priv, orig_node,
 776                                       batadv_ogm_packet->gw_flags);
 777
 778         orig_node->gw_flags = batadv_ogm_packet->gw_flags;
 779
 780         /* restart gateway selection if fast or late switching was enabled */
 781         if ((orig_node->gw_flags) &&
 782             (atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_CLIENT) &&
 783             (atomic_read(&bat_priv->gw_sel_class) > 2))
 784                 batadv_gw_check_election(bat_priv, orig_node);
 785
 786         goto out;
 787
 788 unlock:
 789         rcu_read_unlock();
 790 out:
 791         if (neigh_node)
 792                 batadv_neigh_node_free_ref(neigh_node);
 793         if (router)
 794                 batadv_neigh_node_free_ref(router);
 795 }
 796
 797 static int batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node,
 798                                  struct batadv_orig_node *orig_neigh_node,
 799                                  struct batadv_ogm_packet *batadv_ogm_packet,
 800                                  struct batadv_hard_iface *if_incoming)
 801 {
 802         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 803         struct batadv_neigh_node *neigh_node = NULL, *tmp_neigh_node;
 804         struct hlist_node *node;
 805         uint8_t total_count;
 806         uint8_t orig_eq_count, neigh_rq_count, neigh_rq_inv, tq_own;
 807         unsigned int neigh_rq_inv_cube, neigh_rq_max_cube;
 808         int tq_asym_penalty, inv_asym_penalty, ret = 0;
 809         unsigned int combined_tq;
 810
 811         /* find corresponding one hop neighbor */
 812         rcu_read_lock();
 813         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 814                                  &orig_neigh_node->neigh_list, list) {
 815                 if (!batadv_compare_eth(tmp_neigh_node->addr,
 816                                         orig_neigh_node->orig))
 817                         continue;
 818
 819                 if (tmp_neigh_node->if_incoming != if_incoming)
 820                         continue;
 821
 822                 if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
 823                         continue;
 824
 825                 neigh_node = tmp_neigh_node;
 826                 break;
 827         }
 828         rcu_read_unlock();
 829
 830         if (!neigh_node)
 831                 neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
 832                                                      orig_neigh_node->orig,
 833                                                      orig_neigh_node,
 834                                                      orig_neigh_node,
 835                                                      batadv_ogm_packet->seqno);
 836
 837         if (!neigh_node)
 838                 goto out;
 839
 840         /* if orig_node is direct neighbor update neigh_node last_seen */
 841         if (orig_node == orig_neigh_node)
 842                 neigh_node->last_seen = jiffies;
 843
 844         orig_node->last_seen = jiffies;
 845
 846         /* find packet count of corresponding one hop neighbor */
 847         spin_lock_bh(&orig_node->ogm_cnt_lock);
 848         orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num];
 849         neigh_rq_count = neigh_node->real_packet_count;
 850         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 851
 852         /* pay attention to not get a value bigger than 100 % */
 853         if (orig_eq_count > neigh_rq_count)
 854                 total_count = neigh_rq_count;
 855         else
 856                 total_count = orig_eq_count;
 857
 858         /* if we have too few packets (too less data) we set tq_own to zero
 859          * if we receive too few packets it is not considered bidirectional
 860          */
 861         if (total_count < BATADV_TQ_LOCAL_BIDRECT_SEND_MINIMUM ||
 862             neigh_rq_count < BATADV_TQ_LOCAL_BIDRECT_RECV_MINIMUM)
 863                 tq_own = 0;
 864         else
 865                 /* neigh_node->real_packet_count is never zero as we
 866                  * only purge old information when getting new
 867                  * information
 868                  */
 869                 tq_own = (BATADV_TQ_MAX_VALUE * total_count) /  neigh_rq_count;
 870
 871         /* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
 872          * affect the nearly-symmetric links only a little, but
 873          * punishes asymmetric links more.  This will give a value
 874          * between 0 and TQ_MAX_VALUE
 875          */
 876         neigh_rq_inv = BATADV_TQ_LOCAL_WINDOW_SIZE - neigh_rq_count;
 877         neigh_rq_inv_cube = neigh_rq_inv * neigh_rq_inv * neigh_rq_inv;
 878         neigh_rq_max_cube = BATADV_TQ_LOCAL_WINDOW_SIZE *
 879                             BATADV_TQ_LOCAL_WINDOW_SIZE *
 880                             BATADV_TQ_LOCAL_WINDOW_SIZE;
 881         inv_asym_penalty = BATADV_TQ_MAX_VALUE * neigh_rq_inv_cube;
 882         inv_asym_penalty /= neigh_rq_max_cube;
 883         tq_asym_penalty = BATADV_TQ_MAX_VALUE - inv_asym_penalty;
 884
 885         combined_tq = batadv_ogm_packet->tq * tq_own * tq_asym_penalty;
 886         combined_tq /= BATADV_TQ_MAX_VALUE * BATADV_TQ_MAX_VALUE;
 887         batadv_ogm_packet->tq = combined_tq;
 888
 889         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 890                    "bidirectional: orig = %-15pM neigh = %-15pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, total tq: %3i\n",
 891                    orig_node->orig, orig_neigh_node->orig, total_count,
 892                    neigh_rq_count, tq_own,
 893                    tq_asym_penalty, batadv_ogm_packet->tq);
 894
 895         /* if link has the minimum required transmission quality
 896          * consider it bidirectional
 897          */
 898         if (batadv_ogm_packet->tq >= BATADV_TQ_TOTAL_BIDRECT_LIMIT)
 899                 ret = 1;
 900
 901 out:
 902         if (neigh_node)
 903                 batadv_neigh_node_free_ref(neigh_node);
 904         return ret;
 905 }
 906
 907 /* processes a batman packet for all interfaces, adjusts the sequence number and
 908  * finds out whether it is a duplicate.
 909  * returns:
 910  *   1 the packet is a duplicate
 911  *   0 the packet has not yet been received
 912  *  -1 the packet is old and has been received while the seqno window
 913  *     was protected. Caller should drop it.
 914  */
 915 static int
 916 batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
 917                             const struct batadv_ogm_packet *batadv_ogm_packet,
 918                             const struct batadv_hard_iface *if_incoming)
 919 {
 920         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 921         struct batadv_orig_node *orig_node;
 922         struct batadv_neigh_node *tmp_neigh_node;
 923         struct hlist_node *node;
 924         int is_duplicate = 0;
 925         int32_t seq_diff;
 926         int need_update = 0;
 927         int set_mark, ret = -1;
 928         uint32_t seqno = ntohl(batadv_ogm_packet->seqno);
 929         uint8_t *neigh_addr;
 930         uint8_t packet_count;
 931
 932         orig_node = batadv_get_orig_node(bat_priv, batadv_ogm_packet->orig);
 933         if (!orig_node)
 934                 return 0;
 935
 936         spin_lock_bh(&orig_node->ogm_cnt_lock);
 937         seq_diff = seqno - orig_node->last_real_seqno;
 938
 939         /* signalize caller that the packet is to be dropped. */
 940         if (!hlist_empty(&orig_node->neigh_list) &&
 941             batadv_window_protected(bat_priv, seq_diff,
 942                                     &orig_node->batman_seqno_reset))
 943                 goto out;
 944
 945         rcu_read_lock();
 946         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 947                                  &orig_node->neigh_list, list) {
 948                 is_duplicate |= batadv_test_bit(tmp_neigh_node->real_bits,
 949                                                 orig_node->last_real_seqno,
 950                                                 seqno);
 951
 952                 neigh_addr = tmp_neigh_node->addr;
 953                 if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
 954                     tmp_neigh_node->if_incoming == if_incoming)
 955                         set_mark = 1;
 956                 else
 957                         set_mark = 0;
 958
 959                 /* if the window moved, set the update flag. */
 960                 need_update |= batadv_bit_get_packet(bat_priv,
 961                                                      tmp_neigh_node->real_bits,
 962                                                      seq_diff, set_mark);
 963
 964                 packet_count = bitmap_weight(tmp_neigh_node->real_bits,
 965                                              BATADV_TQ_LOCAL_WINDOW_SIZE);
 966                 tmp_neigh_node->real_packet_count = packet_count;
 967         }
 968         rcu_read_unlock();
 969
 970         if (need_update) {
 971                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 972                            "updating last_seqno: old %u, new %u\n",
 973                            orig_node->last_real_seqno, seqno);
 974                 orig_node->last_real_seqno = seqno;
 975         }
 976
 977         ret = is_duplicate;
 978
 979 out:
 980         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 981         batadv_orig_node_free_ref(orig_node);
 982         return ret;
 983 }
 984
 985 static void batadv_iv_ogm_process(const struct ethhdr *ethhdr,
 986                                   struct batadv_ogm_packet *batadv_ogm_packet,
 987                                   const unsigned char *tt_buff,
 988                                   struct batadv_hard_iface *if_incoming)
 989 {
 990         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 991         struct batadv_hard_iface *hard_iface;
 992         struct batadv_orig_node *orig_neigh_node, *orig_node;
 993         struct batadv_neigh_node *router = NULL, *router_router = NULL;
 994         struct batadv_neigh_node *orig_neigh_router = NULL;
 995         int has_directlink_flag;
 996         int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
 997         int is_broadcast = 0, is_bidirect;
 998         bool is_single_hop_neigh = false;
 999         bool is_from_best_next_hop = false;
1000         int is_duplicate, sameseq, simlar_ttl;
1001         uint32_t if_incoming_seqno;
1002         uint8_t *prev_sender;
1003
1004         /* Silently drop when the batman packet is actually not a
1005          * correct packet.
1006          *
1007          * This might happen if a packet is padded (e.g. Ethernet has a
1008          * minimum frame length of 64 byte) and the aggregation interprets
1009          * it as an additional length.
1010          *
1011          * TODO: A more sane solution would be to have a bit in the
1012          * batadv_ogm_packet to detect whether the packet is the last
1013          * packet in an aggregation.  Here we expect that the padding
1014          * is always zero (or not 0x01)
1015          */
1016         if (batadv_ogm_packet->header.packet_type != BATADV_IV_OGM)
1017                 return;
1018
1019         /* could be changed by schedule_own_packet() */
1020         if_incoming_seqno = atomic_read(&if_incoming->bat_iv.ogm_seqno);
1021
1022         if (batadv_ogm_packet->flags & BATADV_DIRECTLINK)
1023                 has_directlink_flag = 1;
1024         else
1025                 has_directlink_flag = 0;
1026
1027         if (batadv_compare_eth(ethhdr->h_source, batadv_ogm_packet->orig))
1028                 is_single_hop_neigh = true;
1029
1030         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1031                    "Received BATMAN packet via NB: %pM, IF: %s [%pM] (from OG: %pM, via prev OG: %pM, seqno %u, ttvn %u, crc %#.4x, changes %u, tq %d, TTL %d, V %d, IDF %d)\n",
1032                    ethhdr->h_source, if_incoming->net_dev->name,
1033                    if_incoming->net_dev->dev_addr, batadv_ogm_packet->orig,
1034                    batadv_ogm_packet->prev_sender,
1035                    ntohl(batadv_ogm_packet->seqno), batadv_ogm_packet->ttvn,
1036                    ntohs(batadv_ogm_packet->tt_crc),
1037                    batadv_ogm_packet->tt_num_changes, batadv_ogm_packet->tq,
1038                    batadv_ogm_packet->header.ttl,
1039                    batadv_ogm_packet->header.version, has_directlink_flag);
1040
1041         rcu_read_lock();
1042         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
1043                 if (hard_iface->if_status != BATADV_IF_ACTIVE)
1044                         continue;
1045
1046                 if (hard_iface->soft_iface != if_incoming->soft_iface)
1047                         continue;
1048
1049                 if (batadv_compare_eth(ethhdr->h_source,
1050                                        hard_iface->net_dev->dev_addr))
1051                         is_my_addr = 1;
1052
1053                 if (batadv_compare_eth(batadv_ogm_packet->orig,
1054                                        hard_iface->net_dev->dev_addr))
1055                         is_my_orig = 1;
1056
1057                 if (batadv_compare_eth(batadv_ogm_packet->prev_sender,
1058                                        hard_iface->net_dev->dev_addr))
1059                         is_my_oldorig = 1;
1060
1061                 if (is_broadcast_ether_addr(ethhdr->h_source))
1062                         is_broadcast = 1;
1063         }
1064         rcu_read_unlock();
1065
1066         if (batadv_ogm_packet->header.version != BATADV_COMPAT_VERSION) {
1067                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1068                            "Drop packet: incompatible batman version (%i)\n",
1069                            batadv_ogm_packet->header.version);
1070                 return;
1071         }
1072
1073         if (is_my_addr) {
1074                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1075                            "Drop packet: received my own broadcast (sender: %pM)\n",
1076                            ethhdr->h_source);
1077                 return;
1078         }
1079
1080         if (is_broadcast) {
1081                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1082                            "Drop packet: ignoring all packets with broadcast source addr (sender: %pM)\n",
1083                            ethhdr->h_source);
1084                 return;
1085         }
1086
1087         if (is_my_orig) {
1088                 unsigned long *word;
1089                 int offset;
1090                 int32_t bit_pos;
1091                 int16_t if_num;
1092                 uint8_t *weight;
1093
1094                 orig_neigh_node = batadv_get_orig_node(bat_priv,
1095                                                        ethhdr->h_source);
1096                 if (!orig_neigh_node)
1097                         return;
1098
1099                 /* neighbor has to indicate direct link and it has to
1100                  * come via the corresponding interface
1101                  * save packet seqno for bidirectional check
1102                  */
1103                 if (has_directlink_flag &&
1104                     batadv_compare_eth(if_incoming->net_dev->dev_addr,
1105                                        batadv_ogm_packet->orig)) {
1106                         if_num = if_incoming->if_num;
1107                         offset = if_num * BATADV_NUM_WORDS;
1108
1109                         spin_lock_bh(&orig_neigh_node->ogm_cnt_lock);
1110                         word = &(orig_neigh_node->bcast_own[offset]);
1111                         bit_pos = if_incoming_seqno - 2;
1112                         bit_pos -= ntohl(batadv_ogm_packet->seqno);
1113                         batadv_set_bit(word, bit_pos);
1114                         weight = &orig_neigh_node->bcast_own_sum[if_num];
1115                         *weight = bitmap_weight(word,
1116                                                 BATADV_TQ_LOCAL_WINDOW_SIZE);
1117                         spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);
1118                 }
1119
1120                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1121                            "Drop packet: originator packet from myself (via neighbor)\n");
1122                 batadv_orig_node_free_ref(orig_neigh_node);
1123                 return;
1124         }
1125
1126         if (is_my_oldorig) {
1127                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1128                            "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
1129                            ethhdr->h_source);
1130                 return;
1131         }
1132
1133         if (batadv_ogm_packet->flags & BATADV_NOT_BEST_NEXT_HOP) {
1134                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1135                            "Drop packet: ignoring all packets not forwarded from the best next hop (sender: %pM)\n",
1136                            ethhdr->h_source);
1137                 return;
1138         }
1139
1140         orig_node = batadv_get_orig_node(bat_priv, batadv_ogm_packet->orig);
1141         if (!orig_node)
1142                 return;
1143
1144         is_duplicate = batadv_iv_ogm_update_seqnos(ethhdr, batadv_ogm_packet,
1145                                                    if_incoming);
1146
1147         if (is_duplicate == -1) {
1148                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1149                            "Drop packet: packet within seqno protection time (sender: %pM)\n",
1150                            ethhdr->h_source);
1151                 goto out;
1152         }
1153
1154         if (batadv_ogm_packet->tq == 0) {
1155                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1156                            "Drop packet: originator packet with tq equal 0\n");
1157                 goto out;
1158         }
1159
1160         router = batadv_orig_node_get_router(orig_node);
1161         if (router)
1162                 router_router = batadv_orig_node_get_router(router->orig_node);
1163
1164         if ((router && router->tq_avg != 0) &&
1165             (batadv_compare_eth(router->addr, ethhdr->h_source)))
1166                 is_from_best_next_hop = true;
1167
1168         prev_sender = batadv_ogm_packet->prev_sender;
1169         /* avoid temporary routing loops */
1170         if (router && router_router &&
1171             (batadv_compare_eth(router->addr, prev_sender)) &&
1172             !(batadv_compare_eth(batadv_ogm_packet->orig, prev_sender)) &&
1173             (batadv_compare_eth(router->addr, router_router->addr))) {
1174                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1175                            "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
1176                            ethhdr->h_source);
1177                 goto out;
1178         }
1179
1180         /* if sender is a direct neighbor the sender mac equals
1181          * originator mac
1182          */
1183         if (is_single_hop_neigh)
1184                 orig_neigh_node = orig_node;
1185         else
1186                 orig_neigh_node = batadv_get_orig_node(bat_priv,
1187                                                        ethhdr->h_source);
1188
1189         if (!orig_neigh_node)
1190                 goto out;
1191
1192         orig_neigh_router = batadv_orig_node_get_router(orig_neigh_node);
1193
1194         /* drop packet if sender is not a direct neighbor and if we
1195          * don't route towards it
1196          */
1197         if (!is_single_hop_neigh && (!orig_neigh_router)) {
1198                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1199                            "Drop packet: OGM via unknown neighbor!\n");
1200                 goto out_neigh;
1201         }
1202
1203         is_bidirect = batadv_iv_ogm_calc_tq(orig_node, orig_neigh_node,
1204                                             batadv_ogm_packet, if_incoming);
1205
1206         batadv_bonding_save_primary(orig_node, orig_neigh_node,
1207                                     batadv_ogm_packet);
1208
1209         /* update ranking if it is not a duplicate or has the same
1210          * seqno and similar ttl as the non-duplicate
1211          */
1212         sameseq = orig_node->last_real_seqno == ntohl(batadv_ogm_packet->seqno);
1213         simlar_ttl = orig_node->last_ttl - 3 <= batadv_ogm_packet->header.ttl;
1214         if (is_bidirect && (!is_duplicate || (sameseq && simlar_ttl)))
1215                 batadv_iv_ogm_orig_update(bat_priv, orig_node, ethhdr,
1216                                           batadv_ogm_packet, if_incoming,
1217                                           tt_buff, is_duplicate);
1218
1219         /* is single hop (direct) neighbor */
1220         if (is_single_hop_neigh) {
1221                 /* mark direct link on incoming interface */
1222                 batadv_iv_ogm_forward(orig_node, ethhdr, batadv_ogm_packet,
1223                                       is_single_hop_neigh,
1224                                       is_from_best_next_hop, if_incoming);
1225
1226                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1227                            "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
1228                 goto out_neigh;
1229         }
1230
1231         /* multihop originator */
1232         if (!is_bidirect) {
1233                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1234                            "Drop packet: not received via bidirectional link\n");
1235                 goto out_neigh;
1236         }
1237
1238         if (is_duplicate) {
1239                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1240                            "Drop packet: duplicate packet received\n");
1241                 goto out_neigh;
1242         }
1243
1244         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1245                    "Forwarding packet: rebroadcast originator packet\n");
1246         batadv_iv_ogm_forward(orig_node, ethhdr, batadv_ogm_packet,
1247                               is_single_hop_neigh, is_from_best_next_hop,
1248                               if_incoming);
1249
1250 out_neigh:
1251         if ((orig_neigh_node) && (!is_single_hop_neigh))
1252                 batadv_orig_node_free_ref(orig_neigh_node);
1253 out:
1254         if (router)
1255                 batadv_neigh_node_free_ref(router);
1256         if (router_router)
1257                 batadv_neigh_node_free_ref(router_router);
1258         if (orig_neigh_router)
1259                 batadv_neigh_node_free_ref(orig_neigh_router);
1260
1261         batadv_orig_node_free_ref(orig_node);
1262 }
1263
1264 static int batadv_iv_ogm_receive(struct sk_buff *skb,
1265                                  struct batadv_hard_iface *if_incoming)
1266 {
1267         struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
1268         struct batadv_ogm_packet *batadv_ogm_packet;
1269         struct ethhdr *ethhdr;
1270         int buff_pos = 0, packet_len;
1271         unsigned char *tt_buff, *packet_buff;
1272         bool ret;
1273         uint8_t *packet_pos;
1274
1275         ret = batadv_check_management_packet(skb, if_incoming, BATADV_OGM_HLEN);
1276         if (!ret)
1277                 return NET_RX_DROP;
1278
1279         /* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
1280          * that does not have B.A.T.M.A.N. IV enabled ?
1281          */
1282         if (bat_priv->bat_algo_ops->bat_ogm_emit != batadv_iv_ogm_emit)
1283                 return NET_RX_DROP;
1284
1285         batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX);
1286         batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES,
1287                            skb->len + ETH_HLEN);
1288
1289         packet_len = skb_headlen(skb);
1290         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1291         packet_buff = skb->data;
1292         batadv_ogm_packet = (struct batadv_ogm_packet *)packet_buff;
1293
1294         /* unpack the aggregated packets and process them one by one */
1295         do {
1296                 tt_buff = packet_buff + buff_pos + BATADV_OGM_HLEN;
1297
1298                 batadv_iv_ogm_process(ethhdr, batadv_ogm_packet, tt_buff,
1299                                       if_incoming);
1300
1301                 buff_pos += BATADV_OGM_HLEN;
1302                 buff_pos += batadv_tt_len(batadv_ogm_packet->tt_num_changes);
1303
1304                 packet_pos = packet_buff + buff_pos;
1305                 batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
1306         } while (batadv_iv_ogm_aggr_packet(buff_pos, packet_len,
1307                                            batadv_ogm_packet->tt_num_changes));
1308
1309         kfree_skb(skb);
1310         return NET_RX_SUCCESS;
1311 }
1312
1313 static struct batadv_algo_ops batadv_batman_iv __read_mostly = {
1314         .name = "BATMAN_IV",
1315         .bat_iface_enable = batadv_iv_ogm_iface_enable,
1316         .bat_iface_disable = batadv_iv_ogm_iface_disable,
1317         .bat_iface_update_mac = batadv_iv_ogm_iface_update_mac,
1318         .bat_primary_iface_set = batadv_iv_ogm_primary_iface_set,
1319         .bat_ogm_schedule = batadv_iv_ogm_schedule,
1320         .bat_ogm_emit = batadv_iv_ogm_emit,
1321 };
1322
1323 int __init batadv_iv_init(void)
1324 {
1325         int ret;
1326
1327         /* batman originator packet */
1328         ret = batadv_recv_handler_register(BATADV_IV_OGM,
1329                                            batadv_iv_ogm_receive);
1330         if (ret < 0)
1331                 goto out;
1332
1333         ret = batadv_algo_register(&batadv_batman_iv);
1334         if (ret < 0)
1335                 goto handler_unregister;
1336
1337         goto out;
1338
1339 handler_unregister:
1340         batadv_recv_handler_unregister(BATADV_IV_OGM);
1341 out:
1342         return ret;
1343 }