Pileus Git - ~andy/linux/blob - net/batman-adv/routing.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 "routing.h"
  22 #include "send.h"
  23 #include "soft-interface.h"
  24 #include "hard-interface.h"
  25 #include "icmp_socket.h"
  26 #include "translation-table.h"
  27 #include "originator.h"
  28 #include "vis.h"
  29 #include "unicast.h"
  30 #include "bridge_loop_avoidance.h"
  31 #include "distributed-arp-table.h"
  32 #include "network-coding.h"
  33
  34 static int batadv_route_unicast_packet(struct sk_buff *skb,
  35                                        struct batadv_hard_iface *recv_if);
  36
  37 void batadv_slide_own_bcast_window(struct batadv_hard_iface *hard_iface)
  38 {
  39         struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
  40         struct batadv_hashtable *hash = bat_priv->orig_hash;
  41         struct hlist_head *head;
  42         struct batadv_orig_node *orig_node;
  43         unsigned long *word;
  44         uint32_t i;
  45         size_t word_index;
  46         uint8_t *w;
  47
  48         for (i = 0; i < hash->size; i++) {
  49                 head = &hash->table[i];
  50
  51                 rcu_read_lock();
  52                 hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
  53                         spin_lock_bh(&orig_node->ogm_cnt_lock);
  54                         word_index = hard_iface->if_num * BATADV_NUM_WORDS;
  55                         word = &(orig_node->bcast_own[word_index]);
  56
  57                         batadv_bit_get_packet(bat_priv, word, 1, 0);
  58                         w = &orig_node->bcast_own_sum[hard_iface->if_num];
  59                         *w = bitmap_weight(word, BATADV_TQ_LOCAL_WINDOW_SIZE);
  60                         spin_unlock_bh(&orig_node->ogm_cnt_lock);
  61                 }
  62                 rcu_read_unlock();
  63         }
  64 }
  65
  66 static void _batadv_update_route(struct batadv_priv *bat_priv,
  67                                  struct batadv_orig_node *orig_node,
  68                                  struct batadv_neigh_node *neigh_node)
  69 {
  70         struct batadv_neigh_node *curr_router;
  71
  72         curr_router = batadv_orig_node_get_router(orig_node);
  73
  74         /* route deleted */
  75         if ((curr_router) && (!neigh_node)) {
  76                 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
  77                            "Deleting route towards: %pM\n", orig_node->orig);
  78                 batadv_tt_global_del_orig(bat_priv, orig_node,
  79                                           "Deleted route towards originator");
  80
  81         /* route added */
  82         } else if ((!curr_router) && (neigh_node)) {
  83                 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
  84                            "Adding route towards: %pM (via %pM)\n",
  85                            orig_node->orig, neigh_node->addr);
  86         /* route changed */
  87         } else if (neigh_node && curr_router) {
  88                 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
  89                            "Changing route towards: %pM (now via %pM - was via %pM)\n",
  90                            orig_node->orig, neigh_node->addr,
  91                            curr_router->addr);
  92         }
  93
  94         if (curr_router)
  95                 batadv_neigh_node_free_ref(curr_router);
  96
  97         /* increase refcount of new best neighbor */
  98         if (neigh_node && !atomic_inc_not_zero(&neigh_node->refcount))
  99                 neigh_node = NULL;
 100
 101         spin_lock_bh(&orig_node->neigh_list_lock);
 102         rcu_assign_pointer(orig_node->router, neigh_node);
 103         spin_unlock_bh(&orig_node->neigh_list_lock);
 104
 105         /* decrease refcount of previous best neighbor */
 106         if (curr_router)
 107                 batadv_neigh_node_free_ref(curr_router);
 108 }
 109
 110 void batadv_update_route(struct batadv_priv *bat_priv,
 111                          struct batadv_orig_node *orig_node,
 112                          struct batadv_neigh_node *neigh_node)
 113 {
 114         struct batadv_neigh_node *router = NULL;
 115
 116         if (!orig_node)
 117                 goto out;
 118
 119         router = batadv_orig_node_get_router(orig_node);
 120
 121         if (router != neigh_node)
 122                 _batadv_update_route(bat_priv, orig_node, neigh_node);
 123
 124 out:
 125         if (router)
 126                 batadv_neigh_node_free_ref(router);
 127 }
 128
 129 /* caller must hold the neigh_list_lock */
 130 void batadv_bonding_candidate_del(struct batadv_orig_node *orig_node,
 131                                   struct batadv_neigh_node *neigh_node)
 132 {
 133         /* this neighbor is not part of our candidate list */
 134         if (list_empty(&neigh_node->bonding_list))
 135                 goto out;
 136
 137         list_del_rcu(&neigh_node->bonding_list);
 138         INIT_LIST_HEAD(&neigh_node->bonding_list);
 139         batadv_neigh_node_free_ref(neigh_node);
 140         atomic_dec(&orig_node->bond_candidates);
 141
 142 out:
 143         return;
 144 }
 145
 146 void batadv_bonding_candidate_add(struct batadv_orig_node *orig_node,
 147                                   struct batadv_neigh_node *neigh_node)
 148 {
 149         struct batadv_neigh_node *tmp_neigh_node, *router = NULL;
 150         uint8_t interference_candidate = 0;
 151
 152         spin_lock_bh(&orig_node->neigh_list_lock);
 153
 154         /* only consider if it has the same primary address ...  */
 155         if (!batadv_compare_eth(orig_node->orig,
 156                                 neigh_node->orig_node->primary_addr))
 157                 goto candidate_del;
 158
 159         router = batadv_orig_node_get_router(orig_node);
 160         if (!router)
 161                 goto candidate_del;
 162
 163         /* ... and is good enough to be considered */
 164         if (neigh_node->tq_avg < router->tq_avg - BATADV_BONDING_TQ_THRESHOLD)
 165                 goto candidate_del;
 166
 167         /* check if we have another candidate with the same mac address or
 168          * interface. If we do, we won't select this candidate because of
 169          * possible interference.
 170          */
 171         hlist_for_each_entry_rcu(tmp_neigh_node,
 172                                  &orig_node->neigh_list, list) {
 173                 if (tmp_neigh_node == neigh_node)
 174                         continue;
 175
 176                 /* we only care if the other candidate is even
 177                  * considered as candidate.
 178                  */
 179                 if (list_empty(&tmp_neigh_node->bonding_list))
 180                         continue;
 181
 182                 if ((neigh_node->if_incoming == tmp_neigh_node->if_incoming) ||
 183                     (batadv_compare_eth(neigh_node->addr,
 184                                         tmp_neigh_node->addr))) {
 185                         interference_candidate = 1;
 186                         break;
 187                 }
 188         }
 189
 190         /* don't care further if it is an interference candidate */
 191         if (interference_candidate)
 192                 goto candidate_del;
 193
 194         /* this neighbor already is part of our candidate list */
 195         if (!list_empty(&neigh_node->bonding_list))
 196                 goto out;
 197
 198         if (!atomic_inc_not_zero(&neigh_node->refcount))
 199                 goto out;
 200
 201         list_add_rcu(&neigh_node->bonding_list, &orig_node->bond_list);
 202         atomic_inc(&orig_node->bond_candidates);
 203         goto out;
 204
 205 candidate_del:
 206         batadv_bonding_candidate_del(orig_node, neigh_node);
 207
 208 out:
 209         spin_unlock_bh(&orig_node->neigh_list_lock);
 210
 211         if (router)
 212                 batadv_neigh_node_free_ref(router);
 213 }
 214
 215 /* copy primary address for bonding */
 216 void
 217 batadv_bonding_save_primary(const struct batadv_orig_node *orig_node,
 218                             struct batadv_orig_node *orig_neigh_node,
 219                             const struct batadv_ogm_packet *batman_ogm_packet)
 220 {
 221         if (!(batman_ogm_packet->flags & BATADV_PRIMARIES_FIRST_HOP))
 222                 return;
 223
 224         memcpy(orig_neigh_node->primary_addr, orig_node->orig, ETH_ALEN);
 225 }
 226
 227 /* checks whether the host restarted and is in the protection time.
 228  * returns:
 229  *  0 if the packet is to be accepted
 230  *  1 if the packet is to be ignored.
 231  */
 232 int batadv_window_protected(struct batadv_priv *bat_priv, int32_t seq_num_diff,
 233                             unsigned long *last_reset)
 234 {
 235         if (seq_num_diff <= -BATADV_TQ_LOCAL_WINDOW_SIZE ||
 236             seq_num_diff >= BATADV_EXPECTED_SEQNO_RANGE) {
 237                 if (!batadv_has_timed_out(*last_reset,
 238                                           BATADV_RESET_PROTECTION_MS))
 239                         return 1;
 240
 241                 *last_reset = jiffies;
 242                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 243                            "old packet received, start protection\n");
 244         }
 245
 246         return 0;
 247 }
 248
 249 bool batadv_check_management_packet(struct sk_buff *skb,
 250                                     struct batadv_hard_iface *hard_iface,
 251                                     int header_len)
 252 {
 253         struct ethhdr *ethhdr;
 254
 255         /* drop packet if it has not necessary minimum size */
 256         if (unlikely(!pskb_may_pull(skb, header_len)))
 257                 return false;
 258
 259         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 260
 261         /* packet with broadcast indication but unicast recipient */
 262         if (!is_broadcast_ether_addr(ethhdr->h_dest))
 263                 return false;
 264
 265         /* packet with broadcast sender address */
 266         if (is_broadcast_ether_addr(ethhdr->h_source))
 267                 return false;
 268
 269         /* create a copy of the skb, if needed, to modify it. */
 270         if (skb_cow(skb, 0) < 0)
 271                 return false;
 272
 273         /* keep skb linear */
 274         if (skb_linearize(skb) < 0)
 275                 return false;
 276
 277         return true;
 278 }
 279
 280 static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv,
 281                                       struct sk_buff *skb, size_t icmp_len)
 282 {
 283         struct batadv_hard_iface *primary_if = NULL;
 284         struct batadv_orig_node *orig_node = NULL;
 285         struct batadv_icmp_packet_rr *icmp_packet;
 286         int ret = NET_RX_DROP;
 287
 288         icmp_packet = (struct batadv_icmp_packet_rr *)skb->data;
 289
 290         /* add data to device queue */
 291         if (icmp_packet->msg_type != BATADV_ECHO_REQUEST) {
 292                 batadv_socket_receive_packet(icmp_packet, icmp_len);
 293                 goto out;
 294         }
 295
 296         primary_if = batadv_primary_if_get_selected(bat_priv);
 297         if (!primary_if)
 298                 goto out;
 299
 300         /* answer echo request (ping) */
 301         /* get routing information */
 302         orig_node = batadv_orig_hash_find(bat_priv, icmp_packet->orig);
 303         if (!orig_node)
 304                 goto out;
 305
 306         /* create a copy of the skb, if needed, to modify it. */
 307         if (skb_cow(skb, ETH_HLEN) < 0)
 308                 goto out;
 309
 310         icmp_packet = (struct batadv_icmp_packet_rr *)skb->data;
 311
 312         memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
 313         memcpy(icmp_packet->orig, primary_if->net_dev->dev_addr, ETH_ALEN);
 314         icmp_packet->msg_type = BATADV_ECHO_REPLY;
 315         icmp_packet->header.ttl = BATADV_TTL;
 316
 317         if (batadv_send_skb_to_orig(skb, orig_node, NULL))
 318                 ret = NET_RX_SUCCESS;
 319
 320 out:
 321         if (primary_if)
 322                 batadv_hardif_free_ref(primary_if);
 323         if (orig_node)
 324                 batadv_orig_node_free_ref(orig_node);
 325         return ret;
 326 }
 327
 328 static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv,
 329                                          struct sk_buff *skb)
 330 {
 331         struct batadv_hard_iface *primary_if = NULL;
 332         struct batadv_orig_node *orig_node = NULL;
 333         struct batadv_icmp_packet *icmp_packet;
 334         int ret = NET_RX_DROP;
 335
 336         icmp_packet = (struct batadv_icmp_packet *)skb->data;
 337
 338         /* send TTL exceeded if packet is an echo request (traceroute) */
 339         if (icmp_packet->msg_type != BATADV_ECHO_REQUEST) {
 340                 pr_debug("Warning - can't forward icmp packet from %pM to %pM: ttl exceeded\n",
 341                          icmp_packet->orig, icmp_packet->dst);
 342                 goto out;
 343         }
 344
 345         primary_if = batadv_primary_if_get_selected(bat_priv);
 346         if (!primary_if)
 347                 goto out;
 348
 349         /* get routing information */
 350         orig_node = batadv_orig_hash_find(bat_priv, icmp_packet->orig);
 351         if (!orig_node)
 352                 goto out;
 353
 354         /* create a copy of the skb, if needed, to modify it. */
 355         if (skb_cow(skb, ETH_HLEN) < 0)
 356                 goto out;
 357
 358         icmp_packet = (struct batadv_icmp_packet *)skb->data;
 359
 360         memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
 361         memcpy(icmp_packet->orig, primary_if->net_dev->dev_addr, ETH_ALEN);
 362         icmp_packet->msg_type = BATADV_TTL_EXCEEDED;
 363         icmp_packet->header.ttl = BATADV_TTL;
 364
 365         if (batadv_send_skb_to_orig(skb, orig_node, NULL))
 366                 ret = NET_RX_SUCCESS;
 367
 368 out:
 369         if (primary_if)
 370                 batadv_hardif_free_ref(primary_if);
 371         if (orig_node)
 372                 batadv_orig_node_free_ref(orig_node);
 373         return ret;
 374 }
 375
 376
 377 int batadv_recv_icmp_packet(struct sk_buff *skb,
 378                             struct batadv_hard_iface *recv_if)
 379 {
 380         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
 381         struct batadv_icmp_packet_rr *icmp_packet;
 382         struct ethhdr *ethhdr;
 383         struct batadv_orig_node *orig_node = NULL;
 384         int hdr_size = sizeof(struct batadv_icmp_packet);
 385         int ret = NET_RX_DROP;
 386
 387         /* we truncate all incoming icmp packets if they don't match our size */
 388         if (skb->len >= sizeof(struct batadv_icmp_packet_rr))
 389                 hdr_size = sizeof(struct batadv_icmp_packet_rr);
 390
 391         /* drop packet if it has not necessary minimum size */
 392         if (unlikely(!pskb_may_pull(skb, hdr_size)))
 393                 goto out;
 394
 395         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 396
 397         /* packet with unicast indication but broadcast recipient */
 398         if (is_broadcast_ether_addr(ethhdr->h_dest))
 399                 goto out;
 400
 401         /* packet with broadcast sender address */
 402         if (is_broadcast_ether_addr(ethhdr->h_source))
 403                 goto out;
 404
 405         /* not for me */
 406         if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest))
 407                 goto out;
 408
 409         icmp_packet = (struct batadv_icmp_packet_rr *)skb->data;
 410
 411         /* add record route information if not full */
 412         if ((hdr_size == sizeof(struct batadv_icmp_packet_rr)) &&
 413             (icmp_packet->rr_cur < BATADV_RR_LEN)) {
 414                 memcpy(&(icmp_packet->rr[icmp_packet->rr_cur]),
 415                        ethhdr->h_dest, ETH_ALEN);
 416                 icmp_packet->rr_cur++;
 417         }
 418
 419         /* packet for me */
 420         if (batadv_is_my_mac(bat_priv, icmp_packet->dst))
 421                 return batadv_recv_my_icmp_packet(bat_priv, skb, hdr_size);
 422
 423         /* TTL exceeded */
 424         if (icmp_packet->header.ttl < 2)
 425                 return batadv_recv_icmp_ttl_exceeded(bat_priv, skb);
 426
 427         /* get routing information */
 428         orig_node = batadv_orig_hash_find(bat_priv, icmp_packet->dst);
 429         if (!orig_node)
 430                 goto out;
 431
 432         /* create a copy of the skb, if needed, to modify it. */
 433         if (skb_cow(skb, ETH_HLEN) < 0)
 434                 goto out;
 435
 436         icmp_packet = (struct batadv_icmp_packet_rr *)skb->data;
 437
 438         /* decrement ttl */
 439         icmp_packet->header.ttl--;
 440
 441         /* route it */
 442         if (batadv_send_skb_to_orig(skb, orig_node, recv_if))
 443                 ret = NET_RX_SUCCESS;
 444
 445 out:
 446         if (orig_node)
 447                 batadv_orig_node_free_ref(orig_node);
 448         return ret;
 449 }
 450
 451 /* In the bonding case, send the packets in a round
 452  * robin fashion over the remaining interfaces.
 453  *
 454  * This method rotates the bonding list and increases the
 455  * returned router's refcount.
 456  */
 457 static struct batadv_neigh_node *
 458 batadv_find_bond_router(struct batadv_orig_node *primary_orig,
 459                         const struct batadv_hard_iface *recv_if)
 460 {
 461         struct batadv_neigh_node *tmp_neigh_node;
 462         struct batadv_neigh_node *router = NULL, *first_candidate = NULL;
 463
 464         rcu_read_lock();
 465         list_for_each_entry_rcu(tmp_neigh_node, &primary_orig->bond_list,
 466                                 bonding_list) {
 467                 if (!first_candidate)
 468                         first_candidate = tmp_neigh_node;
 469
 470                 /* recv_if == NULL on the first node. */
 471                 if (tmp_neigh_node->if_incoming == recv_if)
 472                         continue;
 473
 474                 if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
 475                         continue;
 476
 477                 router = tmp_neigh_node;
 478                 break;
 479         }
 480
 481         /* use the first candidate if nothing was found. */
 482         if (!router && first_candidate &&
 483             atomic_inc_not_zero(&first_candidate->refcount))
 484                 router = first_candidate;
 485
 486         if (!router)
 487                 goto out;
 488
 489         /* selected should point to the next element
 490          * after the current router
 491          */
 492         spin_lock_bh(&primary_orig->neigh_list_lock);
 493         /* this is a list_move(), which unfortunately
 494          * does not exist as rcu version
 495          */
 496         list_del_rcu(&primary_orig->bond_list);
 497         list_add_rcu(&primary_orig->bond_list,
 498                      &router->bonding_list);
 499         spin_unlock_bh(&primary_orig->neigh_list_lock);
 500
 501 out:
 502         rcu_read_unlock();
 503         return router;
 504 }
 505
 506 /* Interface Alternating: Use the best of the
 507  * remaining candidates which are not using
 508  * this interface.
 509  *
 510  * Increases the returned router's refcount
 511  */
 512 static struct batadv_neigh_node *
 513 batadv_find_ifalter_router(struct batadv_orig_node *primary_orig,
 514                            const struct batadv_hard_iface *recv_if)
 515 {
 516         struct batadv_neigh_node *tmp_neigh_node;
 517         struct batadv_neigh_node *router = NULL, *first_candidate = NULL;
 518
 519         rcu_read_lock();
 520         list_for_each_entry_rcu(tmp_neigh_node, &primary_orig->bond_list,
 521                                 bonding_list) {
 522                 if (!first_candidate)
 523                         first_candidate = tmp_neigh_node;
 524
 525                 /* recv_if == NULL on the first node. */
 526                 if (tmp_neigh_node->if_incoming == recv_if)
 527                         continue;
 528
 529                 if (router && tmp_neigh_node->tq_avg <= router->tq_avg)
 530                         continue;
 531
 532                 if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
 533                         continue;
 534
 535                 /* decrement refcount of previously selected router */
 536                 if (router)
 537                         batadv_neigh_node_free_ref(router);
 538
 539                 /* we found a better router (or at least one valid router) */
 540                 router = tmp_neigh_node;
 541         }
 542
 543         /* use the first candidate if nothing was found. */
 544         if (!router && first_candidate &&
 545             atomic_inc_not_zero(&first_candidate->refcount))
 546                 router = first_candidate;
 547
 548         rcu_read_unlock();
 549         return router;
 550 }
 551
 552 /**
 553  * batadv_check_unicast_packet - Check for malformed unicast packets
 554  * @bat_priv: the bat priv with all the soft interface information
 555  * @skb: packet to check
 556  * @hdr_size: size of header to pull
 557  *
 558  * Check for short header and bad addresses in given packet. Returns negative
 559  * value when check fails and 0 otherwise. The negative value depends on the
 560  * reason: -ENODATA for bad header, -EBADR for broadcast destination or source,
 561  * and -EREMOTE for non-local (other host) destination.
 562  */
 563 static int batadv_check_unicast_packet(struct batadv_priv *bat_priv,
 564                                        struct sk_buff *skb, int hdr_size)
 565 {
 566         struct ethhdr *ethhdr;
 567
 568         /* drop packet if it has not necessary minimum size */
 569         if (unlikely(!pskb_may_pull(skb, hdr_size)))
 570                 return -ENODATA;
 571
 572         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 573
 574         /* packet with unicast indication but broadcast recipient */
 575         if (is_broadcast_ether_addr(ethhdr->h_dest))
 576                 return -EBADR;
 577
 578         /* packet with broadcast sender address */
 579         if (is_broadcast_ether_addr(ethhdr->h_source))
 580                 return -EBADR;
 581
 582         /* not for me */
 583         if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest))
 584                 return -EREMOTE;
 585
 586         return 0;
 587 }
 588
 589 int batadv_recv_tt_query(struct sk_buff *skb, struct batadv_hard_iface *recv_if)
 590 {
 591         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
 592         struct batadv_tt_query_packet *tt_query;
 593         uint16_t tt_size;
 594         int hdr_size = sizeof(*tt_query);
 595         char tt_flag;
 596         size_t packet_size;
 597
 598         if (batadv_check_unicast_packet(bat_priv, skb, hdr_size) < 0)
 599                 return NET_RX_DROP;
 600
 601         /* I could need to modify it */
 602         if (skb_cow(skb, sizeof(struct batadv_tt_query_packet)) < 0)
 603                 goto out;
 604
 605         tt_query = (struct batadv_tt_query_packet *)skb->data;
 606
 607         switch (tt_query->flags & BATADV_TT_QUERY_TYPE_MASK) {
 608         case BATADV_TT_REQUEST:
 609                 batadv_inc_counter(bat_priv, BATADV_CNT_TT_REQUEST_RX);
 610
 611                 /* If we cannot provide an answer the tt_request is
 612                  * forwarded
 613                  */
 614                 if (!batadv_send_tt_response(bat_priv, tt_query)) {
 615                         if (tt_query->flags & BATADV_TT_FULL_TABLE)
 616                                 tt_flag = 'F';
 617                         else
 618                                 tt_flag = '.';
 619
 620                         batadv_dbg(BATADV_DBG_TT, bat_priv,
 621                                    "Routing TT_REQUEST to %pM [%c]\n",
 622                                    tt_query->dst,
 623                                    tt_flag);
 624                         return batadv_route_unicast_packet(skb, recv_if);
 625                 }
 626                 break;
 627         case BATADV_TT_RESPONSE:
 628                 batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_RX);
 629
 630                 if (batadv_is_my_mac(bat_priv, tt_query->dst)) {
 631                         /* packet needs to be linearized to access the TT
 632                          * changes
 633                          */
 634                         if (skb_linearize(skb) < 0)
 635                                 goto out;
 636                         /* skb_linearize() possibly changed skb->data */
 637                         tt_query = (struct batadv_tt_query_packet *)skb->data;
 638
 639                         tt_size = batadv_tt_len(ntohs(tt_query->tt_data));
 640
 641                         /* Ensure we have all the claimed data */
 642                         packet_size = sizeof(struct batadv_tt_query_packet);
 643                         packet_size += tt_size;
 644                         if (unlikely(skb_headlen(skb) < packet_size))
 645                                 goto out;
 646
 647                         batadv_handle_tt_response(bat_priv, tt_query);
 648                 } else {
 649                         if (tt_query->flags & BATADV_TT_FULL_TABLE)
 650                                 tt_flag =  'F';
 651                         else
 652                                 tt_flag = '.';
 653                         batadv_dbg(BATADV_DBG_TT, bat_priv,
 654                                    "Routing TT_RESPONSE to %pM [%c]\n",
 655                                    tt_query->dst,
 656                                    tt_flag);
 657                         return batadv_route_unicast_packet(skb, recv_if);
 658                 }
 659                 break;
 660         }
 661
 662 out:
 663         /* returning NET_RX_DROP will make the caller function kfree the skb */
 664         return NET_RX_DROP;
 665 }
 666
 667 int batadv_recv_roam_adv(struct sk_buff *skb, struct batadv_hard_iface *recv_if)
 668 {
 669         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
 670         struct batadv_roam_adv_packet *roam_adv_packet;
 671         struct batadv_orig_node *orig_node;
 672
 673         if (batadv_check_unicast_packet(bat_priv, skb,
 674                                         sizeof(*roam_adv_packet)) < 0)
 675                 goto out;
 676
 677         batadv_inc_counter(bat_priv, BATADV_CNT_TT_ROAM_ADV_RX);
 678
 679         roam_adv_packet = (struct batadv_roam_adv_packet *)skb->data;
 680
 681         if (!batadv_is_my_mac(bat_priv, roam_adv_packet->dst))
 682                 return batadv_route_unicast_packet(skb, recv_if);
 683
 684         /* check if it is a backbone gateway. we don't accept
 685          * roaming advertisement from it, as it has the same
 686          * entries as we have.
 687          */
 688         if (batadv_bla_is_backbone_gw_orig(bat_priv, roam_adv_packet->src))
 689                 goto out;
 690
 691         orig_node = batadv_orig_hash_find(bat_priv, roam_adv_packet->src);
 692         if (!orig_node)
 693                 goto out;
 694
 695         batadv_dbg(BATADV_DBG_TT, bat_priv,
 696                    "Received ROAMING_ADV from %pM (client %pM)\n",
 697                    roam_adv_packet->src, roam_adv_packet->client);
 698
 699         batadv_tt_global_add(bat_priv, orig_node, roam_adv_packet->client,
 700                              BATADV_TT_CLIENT_ROAM,
 701                              atomic_read(&orig_node->last_ttvn) + 1);
 702
 703         batadv_orig_node_free_ref(orig_node);
 704 out:
 705         /* returning NET_RX_DROP will make the caller function kfree the skb */
 706         return NET_RX_DROP;
 707 }
 708
 709 /* find a suitable router for this originator, and use
 710  * bonding if possible. increases the found neighbors
 711  * refcount.
 712  */
 713 struct batadv_neigh_node *
 714 batadv_find_router(struct batadv_priv *bat_priv,
 715                    struct batadv_orig_node *orig_node,
 716                    const struct batadv_hard_iface *recv_if)
 717 {
 718         struct batadv_orig_node *primary_orig_node;
 719         struct batadv_orig_node *router_orig;
 720         struct batadv_neigh_node *router;
 721         static uint8_t zero_mac[ETH_ALEN] = {0, 0, 0, 0, 0, 0};
 722         int bonding_enabled;
 723         uint8_t *primary_addr;
 724
 725         if (!orig_node)
 726                 return NULL;
 727
 728         router = batadv_orig_node_get_router(orig_node);
 729         if (!router)
 730                 goto err;
 731
 732         /* without bonding, the first node should
 733          * always choose the default router.
 734          */
 735         bonding_enabled = atomic_read(&bat_priv->bonding);
 736
 737         rcu_read_lock();
 738         /* select default router to output */
 739         router_orig = router->orig_node;
 740         if (!router_orig)
 741                 goto err_unlock;
 742
 743         if ((!recv_if) && (!bonding_enabled))
 744                 goto return_router;
 745
 746         primary_addr = router_orig->primary_addr;
 747
 748         /* if we have something in the primary_addr, we can search
 749          * for a potential bonding candidate.
 750          */
 751         if (batadv_compare_eth(primary_addr, zero_mac))
 752                 goto return_router;
 753
 754         /* find the orig_node which has the primary interface. might
 755          * even be the same as our router_orig in many cases
 756          */
 757         if (batadv_compare_eth(primary_addr, router_orig->orig)) {
 758                 primary_orig_node = router_orig;
 759         } else {
 760                 primary_orig_node = batadv_orig_hash_find(bat_priv,
 761                                                           primary_addr);
 762                 if (!primary_orig_node)
 763                         goto return_router;
 764
 765                 batadv_orig_node_free_ref(primary_orig_node);
 766         }
 767
 768         /* with less than 2 candidates, we can't do any
 769          * bonding and prefer the original router.
 770          */
 771         if (atomic_read(&primary_orig_node->bond_candidates) < 2)
 772                 goto return_router;
 773
 774         /* all nodes between should choose a candidate which
 775          * is is not on the interface where the packet came
 776          * in.
 777          */
 778         batadv_neigh_node_free_ref(router);
 779
 780         if (bonding_enabled)
 781                 router = batadv_find_bond_router(primary_orig_node, recv_if);
 782         else
 783                 router = batadv_find_ifalter_router(primary_orig_node, recv_if);
 784
 785 return_router:
 786         if (router && router->if_incoming->if_status != BATADV_IF_ACTIVE)
 787                 goto err_unlock;
 788
 789         rcu_read_unlock();
 790         return router;
 791 err_unlock:
 792         rcu_read_unlock();
 793 err:
 794         if (router)
 795                 batadv_neigh_node_free_ref(router);
 796         return NULL;
 797 }
 798
 799 static int batadv_route_unicast_packet(struct sk_buff *skb,
 800                                        struct batadv_hard_iface *recv_if)
 801 {
 802         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
 803         struct batadv_orig_node *orig_node = NULL;
 804         struct batadv_neigh_node *neigh_node = NULL;
 805         struct batadv_unicast_packet *unicast_packet;
 806         struct ethhdr *ethhdr = (struct ethhdr *)skb_mac_header(skb);
 807         int ret = NET_RX_DROP;
 808         struct sk_buff *new_skb;
 809
 810         unicast_packet = (struct batadv_unicast_packet *)skb->data;
 811
 812         /* TTL exceeded */
 813         if (unicast_packet->header.ttl < 2) {
 814                 pr_debug("Warning - can't forward unicast packet from %pM to %pM: ttl exceeded\n",
 815                          ethhdr->h_source, unicast_packet->dest);
 816                 goto out;
 817         }
 818
 819         /* get routing information */
 820         orig_node = batadv_orig_hash_find(bat_priv, unicast_packet->dest);
 821
 822         if (!orig_node)
 823                 goto out;
 824
 825         /* find_router() increases neigh_nodes refcount if found. */
 826         neigh_node = batadv_find_router(bat_priv, orig_node, recv_if);
 827
 828         if (!neigh_node)
 829                 goto out;
 830
 831         /* create a copy of the skb, if needed, to modify it. */
 832         if (skb_cow(skb, ETH_HLEN) < 0)
 833                 goto out;
 834
 835         unicast_packet = (struct batadv_unicast_packet *)skb->data;
 836
 837         if (unicast_packet->header.packet_type == BATADV_UNICAST &&
 838             atomic_read(&bat_priv->fragmentation) &&
 839             skb->len > neigh_node->if_incoming->net_dev->mtu) {
 840                 ret = batadv_frag_send_skb(skb, bat_priv,
 841                                            neigh_node->if_incoming,
 842                                            neigh_node->addr);
 843                 goto out;
 844         }
 845
 846         if (unicast_packet->header.packet_type == BATADV_UNICAST_FRAG &&
 847             batadv_frag_can_reassemble(skb,
 848                                        neigh_node->if_incoming->net_dev->mtu)) {
 849                 ret = batadv_frag_reassemble_skb(skb, bat_priv, &new_skb);
 850
 851                 if (ret == NET_RX_DROP)
 852                         goto out;
 853
 854                 /* packet was buffered for late merge */
 855                 if (!new_skb) {
 856                         ret = NET_RX_SUCCESS;
 857                         goto out;
 858                 }
 859
 860                 skb = new_skb;
 861                 unicast_packet = (struct batadv_unicast_packet *)skb->data;
 862         }
 863
 864         /* decrement ttl */
 865         unicast_packet->header.ttl--;
 866
 867         /* network code packet if possible */
 868         if (batadv_nc_skb_forward(skb, neigh_node, ethhdr)) {
 869                 ret = NET_RX_SUCCESS;
 870         } else if (batadv_send_skb_to_orig(skb, orig_node, recv_if)) {
 871                 ret = NET_RX_SUCCESS;
 872
 873                 /* Update stats counter */
 874                 batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD);
 875                 batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES,
 876                                    skb->len + ETH_HLEN);
 877         }
 878
 879 out:
 880         if (neigh_node)
 881                 batadv_neigh_node_free_ref(neigh_node);
 882         if (orig_node)
 883                 batadv_orig_node_free_ref(orig_node);
 884         return ret;
 885 }
 886
 887 /**
 888  * batadv_reroute_unicast_packet - update the unicast header for re-routing
 889  * @bat_priv: the bat priv with all the soft interface information
 890  * @unicast_packet: the unicast header to be updated
 891  * @dst_addr: the payload destination
 892  *
 893  * Search the translation table for dst_addr and update the unicast header with
 894  * the new corresponding information (originator address where the destination
 895  * client currently is and its known TTVN)
 896  *
 897  * Returns true if the packet header has been updated, false otherwise
 898  */
 899 static bool
 900 batadv_reroute_unicast_packet(struct batadv_priv *bat_priv,
 901                               struct batadv_unicast_packet *unicast_packet,
 902                               uint8_t *dst_addr)
 903 {
 904         struct batadv_orig_node *orig_node = NULL;
 905         struct batadv_hard_iface *primary_if = NULL;
 906         bool ret = false;
 907         uint8_t *orig_addr, orig_ttvn;
 908
 909         if (batadv_is_my_client(bat_priv, dst_addr)) {
 910                 primary_if = batadv_primary_if_get_selected(bat_priv);
 911                 if (!primary_if)
 912                         goto out;
 913                 orig_addr = primary_if->net_dev->dev_addr;
 914                 orig_ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn);
 915         } else {
 916                 orig_node = batadv_transtable_search(bat_priv, NULL, dst_addr);
 917                 if (!orig_node)
 918                         goto out;
 919
 920                 if (batadv_compare_eth(orig_node->orig, unicast_packet->dest))
 921                         goto out;
 922
 923                 orig_addr = orig_node->orig;
 924                 orig_ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
 925         }
 926
 927         /* update the packet header */
 928         memcpy(unicast_packet->dest, orig_addr, ETH_ALEN);
 929         unicast_packet->ttvn = orig_ttvn;
 930
 931         ret = true;
 932 out:
 933         if (primary_if)
 934                 batadv_hardif_free_ref(primary_if);
 935         if (orig_node)
 936                 batadv_orig_node_free_ref(orig_node);
 937
 938         return ret;
 939 }
 940
 941 static int batadv_check_unicast_ttvn(struct batadv_priv *bat_priv,
 942                                      struct sk_buff *skb, int hdr_len) {
 943         uint8_t curr_ttvn, old_ttvn;
 944         struct batadv_orig_node *orig_node;
 945         struct ethhdr *ethhdr;
 946         struct batadv_hard_iface *primary_if;
 947         struct batadv_unicast_packet *unicast_packet;
 948         int is_old_ttvn;
 949
 950         /* check if there is enough data before accessing it */
 951         if (pskb_may_pull(skb, hdr_len + ETH_HLEN) < 0)
 952                 return 0;
 953
 954         /* create a copy of the skb (in case of for re-routing) to modify it. */
 955         if (skb_cow(skb, sizeof(*unicast_packet)) < 0)
 956                 return 0;
 957
 958         unicast_packet = (struct batadv_unicast_packet *)skb->data;
 959         ethhdr = (struct ethhdr *)(skb->data + hdr_len);
 960
 961         /* check if the destination client was served by this node and it is now
 962          * roaming. In this case, it means that the node has got a ROAM_ADV
 963          * message and that it knows the new destination in the mesh to re-route
 964          * the packet to
 965          */
 966         if (batadv_tt_local_client_is_roaming(bat_priv, ethhdr->h_dest)) {
 967                 if (batadv_reroute_unicast_packet(bat_priv, unicast_packet,
 968                                                   ethhdr->h_dest))
 969                         net_ratelimited_function(batadv_dbg, BATADV_DBG_TT,
 970                                                  bat_priv,
 971                                                  "Rerouting unicast packet to %pM (dst=%pM): Local Roaming\n",
 972                                                  unicast_packet->dest,
 973                                                  ethhdr->h_dest);
 974                 /* at this point the mesh destination should have been
 975                  * substituted with the originator address found in the global
 976                  * table. If not, let the packet go untouched anyway because
 977                  * there is nothing the node can do
 978                  */
 979                 return 1;
 980         }
 981
 982         /* retrieve the TTVN known by this node for the packet destination. This
 983          * value is used later to check if the node which sent (or re-routed
 984          * last time) the packet had an updated information or not
 985          */
 986         curr_ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn);
 987         if (!batadv_is_my_mac(bat_priv, unicast_packet->dest)) {
 988                 orig_node = batadv_orig_hash_find(bat_priv,
 989                                                   unicast_packet->dest);
 990                 /* if it is not possible to find the orig_node representing the
 991                  * destination, the packet can immediately be dropped as it will
 992                  * not be possible to deliver it
 993                  */
 994                 if (!orig_node)
 995                         return 0;
 996
 997                 curr_ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
 998                 batadv_orig_node_free_ref(orig_node);
 999         }
1000
1001         /* check if the TTVN contained in the packet is fresher than what the
1002          * node knows
1003          */
1004         is_old_ttvn = batadv_seq_before(unicast_packet->ttvn, curr_ttvn);
1005         if (!is_old_ttvn)
1006                 return 1;
1007
1008         old_ttvn = unicast_packet->ttvn;
1009         /* the packet was forged based on outdated network information. Its
1010          * destination can possibly be updated and forwarded towards the new
1011          * target host
1012          */
1013         if (batadv_reroute_unicast_packet(bat_priv, unicast_packet,
1014                                           ethhdr->h_dest)) {
1015                 net_ratelimited_function(batadv_dbg, BATADV_DBG_TT, bat_priv,
1016                                          "Rerouting unicast packet to %pM (dst=%pM): TTVN mismatch old_ttvn=%u new_ttvn=%u\n",
1017                                          unicast_packet->dest, ethhdr->h_dest,
1018                                          old_ttvn, curr_ttvn);
1019                 return 1;
1020         }
1021
1022         /* the packet has not been re-routed: either the destination is
1023          * currently served by this node or there is no destination at all and
1024          * it is possible to drop the packet
1025          */
1026         if (!batadv_is_my_client(bat_priv, ethhdr->h_dest))
1027                 return 0;
1028
1029         /* update the header in order to let the packet be delivered to this
1030          * node's soft interface
1031          */
1032         primary_if = batadv_primary_if_get_selected(bat_priv);
1033         if (!primary_if)
1034                 return 0;
1035
1036         memcpy(unicast_packet->dest, primary_if->net_dev->dev_addr, ETH_ALEN);
1037
1038         batadv_hardif_free_ref(primary_if);
1039
1040         unicast_packet->ttvn = curr_ttvn;
1041
1042         return 1;
1043 }
1044
1045 int batadv_recv_unicast_packet(struct sk_buff *skb,
1046                                struct batadv_hard_iface *recv_if)
1047 {
1048         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1049         struct batadv_unicast_packet *unicast_packet;
1050         struct batadv_unicast_4addr_packet *unicast_4addr_packet;
1051         uint8_t *orig_addr;
1052         struct batadv_orig_node *orig_node = NULL;
1053         int check, hdr_size = sizeof(*unicast_packet);
1054         bool is4addr;
1055
1056         unicast_packet = (struct batadv_unicast_packet *)skb->data;
1057         unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
1058
1059         is4addr = unicast_packet->header.packet_type == BATADV_UNICAST_4ADDR;
1060         /* the caller function should have already pulled 2 bytes */
1061         if (is4addr)
1062                 hdr_size = sizeof(*unicast_4addr_packet);
1063
1064         /* function returns -EREMOTE for promiscuous packets */
1065         check = batadv_check_unicast_packet(bat_priv, skb, hdr_size);
1066
1067         /* Even though the packet is not for us, we might save it to use for
1068          * decoding a later received coded packet
1069          */
1070         if (check == -EREMOTE)
1071                 batadv_nc_skb_store_sniffed_unicast(bat_priv, skb);
1072
1073         if (check < 0)
1074                 return NET_RX_DROP;
1075         if (!batadv_check_unicast_ttvn(bat_priv, skb, hdr_size))
1076                 return NET_RX_DROP;
1077
1078         /* packet for me */
1079         if (batadv_is_my_mac(bat_priv, unicast_packet->dest)) {
1080                 if (is4addr) {
1081                         batadv_dat_inc_counter(bat_priv,
1082                                                unicast_4addr_packet->subtype);
1083                         orig_addr = unicast_4addr_packet->src;
1084                         orig_node = batadv_orig_hash_find(bat_priv, orig_addr);
1085                 }
1086
1087                 if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb,
1088                                                           hdr_size))
1089                         goto rx_success;
1090                 if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb,
1091                                                         hdr_size))
1092                         goto rx_success;
1093
1094                 batadv_interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size,
1095                                     orig_node);
1096
1097 rx_success:
1098                 if (orig_node)
1099                         batadv_orig_node_free_ref(orig_node);
1100
1101                 return NET_RX_SUCCESS;
1102         }
1103
1104         return batadv_route_unicast_packet(skb, recv_if);
1105 }
1106
1107 int batadv_recv_ucast_frag_packet(struct sk_buff *skb,
1108                                   struct batadv_hard_iface *recv_if)
1109 {
1110         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1111         struct batadv_unicast_frag_packet *unicast_packet;
1112         int hdr_size = sizeof(*unicast_packet);
1113         struct sk_buff *new_skb = NULL;
1114         int ret;
1115
1116         if (batadv_check_unicast_packet(bat_priv, skb, hdr_size) < 0)
1117                 return NET_RX_DROP;
1118
1119         if (!batadv_check_unicast_ttvn(bat_priv, skb, hdr_size))
1120                 return NET_RX_DROP;
1121
1122         unicast_packet = (struct batadv_unicast_frag_packet *)skb->data;
1123
1124         /* packet for me */
1125         if (batadv_is_my_mac(bat_priv, unicast_packet->dest)) {
1126                 ret = batadv_frag_reassemble_skb(skb, bat_priv, &new_skb);
1127
1128                 if (ret == NET_RX_DROP)
1129                         return NET_RX_DROP;
1130
1131                 /* packet was buffered for late merge */
1132                 if (!new_skb)
1133                         return NET_RX_SUCCESS;
1134
1135                 if (batadv_dat_snoop_incoming_arp_request(bat_priv, new_skb,
1136                                                           hdr_size))
1137                         goto rx_success;
1138                 if (batadv_dat_snoop_incoming_arp_reply(bat_priv, new_skb,
1139                                                         hdr_size))
1140                         goto rx_success;
1141
1142                 batadv_interface_rx(recv_if->soft_iface, new_skb, recv_if,
1143                                     sizeof(struct batadv_unicast_packet), NULL);
1144
1145 rx_success:
1146                 return NET_RX_SUCCESS;
1147         }
1148
1149         return batadv_route_unicast_packet(skb, recv_if);
1150 }
1151
1152
1153 int batadv_recv_bcast_packet(struct sk_buff *skb,
1154                              struct batadv_hard_iface *recv_if)
1155 {
1156         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1157         struct batadv_orig_node *orig_node = NULL;
1158         struct batadv_bcast_packet *bcast_packet;
1159         struct ethhdr *ethhdr;
1160         int hdr_size = sizeof(*bcast_packet);
1161         int ret = NET_RX_DROP;
1162         int32_t seq_diff;
1163
1164         /* drop packet if it has not necessary minimum size */
1165         if (unlikely(!pskb_may_pull(skb, hdr_size)))
1166                 goto out;
1167
1168         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1169
1170         /* packet with broadcast indication but unicast recipient */
1171         if (!is_broadcast_ether_addr(ethhdr->h_dest))
1172                 goto out;
1173
1174         /* packet with broadcast sender address */
1175         if (is_broadcast_ether_addr(ethhdr->h_source))
1176                 goto out;
1177
1178         /* ignore broadcasts sent by myself */
1179         if (batadv_is_my_mac(bat_priv, ethhdr->h_source))
1180                 goto out;
1181
1182         bcast_packet = (struct batadv_bcast_packet *)skb->data;
1183
1184         /* ignore broadcasts originated by myself */
1185         if (batadv_is_my_mac(bat_priv, bcast_packet->orig))
1186                 goto out;
1187
1188         if (bcast_packet->header.ttl < 2)
1189                 goto out;
1190
1191         orig_node = batadv_orig_hash_find(bat_priv, bcast_packet->orig);
1192
1193         if (!orig_node)
1194                 goto out;
1195
1196         spin_lock_bh(&orig_node->bcast_seqno_lock);
1197
1198         /* check whether the packet is a duplicate */
1199         if (batadv_test_bit(orig_node->bcast_bits, orig_node->last_bcast_seqno,
1200                             ntohl(bcast_packet->seqno)))
1201                 goto spin_unlock;
1202
1203         seq_diff = ntohl(bcast_packet->seqno) - orig_node->last_bcast_seqno;
1204
1205         /* check whether the packet is old and the host just restarted. */
1206         if (batadv_window_protected(bat_priv, seq_diff,
1207                                     &orig_node->bcast_seqno_reset))
1208                 goto spin_unlock;
1209
1210         /* mark broadcast in flood history, update window position
1211          * if required.
1212          */
1213         if (batadv_bit_get_packet(bat_priv, orig_node->bcast_bits, seq_diff, 1))
1214                 orig_node->last_bcast_seqno = ntohl(bcast_packet->seqno);
1215
1216         spin_unlock_bh(&orig_node->bcast_seqno_lock);
1217
1218         /* check whether this has been sent by another originator before */
1219         if (batadv_bla_check_bcast_duplist(bat_priv, skb))
1220                 goto out;
1221
1222         /* rebroadcast packet */
1223         batadv_add_bcast_packet_to_list(bat_priv, skb, 1);
1224
1225         /* don't hand the broadcast up if it is from an originator
1226          * from the same backbone.
1227          */
1228         if (batadv_bla_is_backbone_gw(skb, orig_node, hdr_size))
1229                 goto out;
1230
1231         if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb, hdr_size))
1232                 goto rx_success;
1233         if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb, hdr_size))
1234                 goto rx_success;
1235
1236         /* broadcast for me */
1237         batadv_interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size,
1238                             orig_node);
1239
1240 rx_success:
1241         ret = NET_RX_SUCCESS;
1242         goto out;
1243
1244 spin_unlock:
1245         spin_unlock_bh(&orig_node->bcast_seqno_lock);
1246 out:
1247         if (orig_node)
1248                 batadv_orig_node_free_ref(orig_node);
1249         return ret;
1250 }
1251
1252 int batadv_recv_vis_packet(struct sk_buff *skb,
1253                            struct batadv_hard_iface *recv_if)
1254 {
1255         struct batadv_vis_packet *vis_packet;
1256         struct ethhdr *ethhdr;
1257         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1258         int hdr_size = sizeof(*vis_packet);
1259
1260         /* keep skb linear */
1261         if (skb_linearize(skb) < 0)
1262                 return NET_RX_DROP;
1263
1264         if (unlikely(!pskb_may_pull(skb, hdr_size)))
1265                 return NET_RX_DROP;
1266
1267         vis_packet = (struct batadv_vis_packet *)skb->data;
1268         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1269
1270         /* not for me */
1271         if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest))
1272                 return NET_RX_DROP;
1273
1274         /* ignore own packets */
1275         if (batadv_is_my_mac(bat_priv, vis_packet->vis_orig))
1276                 return NET_RX_DROP;
1277
1278         if (batadv_is_my_mac(bat_priv, vis_packet->sender_orig))
1279                 return NET_RX_DROP;
1280
1281         switch (vis_packet->vis_type) {
1282         case BATADV_VIS_TYPE_SERVER_SYNC:
1283                 batadv_receive_server_sync_packet(bat_priv, vis_packet,
1284                                                   skb_headlen(skb));
1285                 break;
1286
1287         case BATADV_VIS_TYPE_CLIENT_UPDATE:
1288                 batadv_receive_client_update_packet(bat_priv, vis_packet,
1289                                                     skb_headlen(skb));
1290                 break;
1291
1292         default:        /* ignore unknown packet */
1293                 break;
1294         }
1295
1296         /* We take a copy of the data in the packet, so we should
1297          * always free the skbuf.
1298          */
1299         return NET_RX_DROP;
1300 }