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 static void _batadv_update_route(struct batadv_priv *bat_priv,
  38                                  struct batadv_orig_node *orig_node,
  39                                  struct batadv_neigh_node *neigh_node)
  40 {
  41         struct batadv_neigh_node *curr_router;
  42
  43         curr_router = batadv_orig_node_get_router(orig_node);
  44
  45         /* route deleted */
  46         if ((curr_router) && (!neigh_node)) {
  47                 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
  48                            "Deleting route towards: %pM\n", orig_node->orig);
  49                 batadv_tt_global_del_orig(bat_priv, orig_node,
  50                                           "Deleted route towards originator");
  51
  52         /* route added */
  53         } else if ((!curr_router) && (neigh_node)) {
  54                 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
  55                            "Adding route towards: %pM (via %pM)\n",
  56                            orig_node->orig, neigh_node->addr);
  57         /* route changed */
  58         } else if (neigh_node && curr_router) {
  59                 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
  60                            "Changing route towards: %pM (now via %pM - was via %pM)\n",
  61                            orig_node->orig, neigh_node->addr,
  62                            curr_router->addr);
  63         }
  64
  65         if (curr_router)
  66                 batadv_neigh_node_free_ref(curr_router);
  67
  68         /* increase refcount of new best neighbor */
  69         if (neigh_node && !atomic_inc_not_zero(&neigh_node->refcount))
  70                 neigh_node = NULL;
  71
  72         spin_lock_bh(&orig_node->neigh_list_lock);
  73         /* curr_router used earlier may not be the current orig_node->router
  74          * anymore because it was dereferenced outside of the neigh_list_lock
  75          * protected region. After the new best neighbor has replace the current
  76          * best neighbor the reference counter needs to decrease. Consequently,
  77          * the code needs to ensure the curr_router variable contains a pointer
  78          * to the replaced best neighbor.
  79          */
  80         curr_router = rcu_dereference_protected(orig_node->router, true);
  81
  82         rcu_assign_pointer(orig_node->router, neigh_node);
  83         spin_unlock_bh(&orig_node->neigh_list_lock);
  84
  85         /* decrease refcount of previous best neighbor */
  86         if (curr_router)
  87                 batadv_neigh_node_free_ref(curr_router);
  88 }
  89
  90 void batadv_update_route(struct batadv_priv *bat_priv,
  91                          struct batadv_orig_node *orig_node,
  92                          struct batadv_neigh_node *neigh_node)
  93 {
  94         struct batadv_neigh_node *router = NULL;
  95
  96         if (!orig_node)
  97                 goto out;
  98
  99         router = batadv_orig_node_get_router(orig_node);
 100
 101         if (router != neigh_node)
 102                 _batadv_update_route(bat_priv, orig_node, neigh_node);
 103
 104 out:
 105         if (router)
 106                 batadv_neigh_node_free_ref(router);
 107 }
 108
 109 /* caller must hold the neigh_list_lock */
 110 void batadv_bonding_candidate_del(struct batadv_orig_node *orig_node,
 111                                   struct batadv_neigh_node *neigh_node)
 112 {
 113         /* this neighbor is not part of our candidate list */
 114         if (list_empty(&neigh_node->bonding_list))
 115                 goto out;
 116
 117         list_del_rcu(&neigh_node->bonding_list);
 118         INIT_LIST_HEAD(&neigh_node->bonding_list);
 119         batadv_neigh_node_free_ref(neigh_node);
 120         atomic_dec(&orig_node->bond_candidates);
 121
 122 out:
 123         return;
 124 }
 125
 126 void batadv_bonding_candidate_add(struct batadv_orig_node *orig_node,
 127                                   struct batadv_neigh_node *neigh_node)
 128 {
 129         struct batadv_neigh_node *tmp_neigh_node, *router = NULL;
 130         uint8_t interference_candidate = 0;
 131
 132         spin_lock_bh(&orig_node->neigh_list_lock);
 133
 134         /* only consider if it has the same primary address ...  */
 135         if (!batadv_compare_eth(orig_node->orig,
 136                                 neigh_node->orig_node->primary_addr))
 137                 goto candidate_del;
 138
 139         router = batadv_orig_node_get_router(orig_node);
 140         if (!router)
 141                 goto candidate_del;
 142
 143         /* ... and is good enough to be considered */
 144         if (neigh_node->tq_avg < router->tq_avg - BATADV_BONDING_TQ_THRESHOLD)
 145                 goto candidate_del;
 146
 147         /* check if we have another candidate with the same mac address or
 148          * interface. If we do, we won't select this candidate because of
 149          * possible interference.
 150          */
 151         hlist_for_each_entry_rcu(tmp_neigh_node,
 152                                  &orig_node->neigh_list, list) {
 153                 if (tmp_neigh_node == neigh_node)
 154                         continue;
 155
 156                 /* we only care if the other candidate is even
 157                  * considered as candidate.
 158                  */
 159                 if (list_empty(&tmp_neigh_node->bonding_list))
 160                         continue;
 161
 162                 if ((neigh_node->if_incoming == tmp_neigh_node->if_incoming) ||
 163                     (batadv_compare_eth(neigh_node->addr,
 164                                         tmp_neigh_node->addr))) {
 165                         interference_candidate = 1;
 166                         break;
 167                 }
 168         }
 169
 170         /* don't care further if it is an interference candidate */
 171         if (interference_candidate)
 172                 goto candidate_del;
 173
 174         /* this neighbor already is part of our candidate list */
 175         if (!list_empty(&neigh_node->bonding_list))
 176                 goto out;
 177
 178         if (!atomic_inc_not_zero(&neigh_node->refcount))
 179                 goto out;
 180
 181         list_add_rcu(&neigh_node->bonding_list, &orig_node->bond_list);
 182         atomic_inc(&orig_node->bond_candidates);
 183         goto out;
 184
 185 candidate_del:
 186         batadv_bonding_candidate_del(orig_node, neigh_node);
 187
 188 out:
 189         spin_unlock_bh(&orig_node->neigh_list_lock);
 190
 191         if (router)
 192                 batadv_neigh_node_free_ref(router);
 193 }
 194
 195 /* copy primary address for bonding */
 196 void
 197 batadv_bonding_save_primary(const struct batadv_orig_node *orig_node,
 198                             struct batadv_orig_node *orig_neigh_node,
 199                             const struct batadv_ogm_packet *batman_ogm_packet)
 200 {
 201         if (!(batman_ogm_packet->flags & BATADV_PRIMARIES_FIRST_HOP))
 202                 return;
 203
 204         memcpy(orig_neigh_node->primary_addr, orig_node->orig, ETH_ALEN);
 205 }
 206
 207 /* checks whether the host restarted and is in the protection time.
 208  * returns:
 209  *  0 if the packet is to be accepted
 210  *  1 if the packet is to be ignored.
 211  */
 212 int batadv_window_protected(struct batadv_priv *bat_priv, int32_t seq_num_diff,
 213                             unsigned long *last_reset)
 214 {
 215         if (seq_num_diff <= -BATADV_TQ_LOCAL_WINDOW_SIZE ||
 216             seq_num_diff >= BATADV_EXPECTED_SEQNO_RANGE) {
 217                 if (!batadv_has_timed_out(*last_reset,
 218                                           BATADV_RESET_PROTECTION_MS))
 219                         return 1;
 220
 221                 *last_reset = jiffies;
 222                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 223                            "old packet received, start protection\n");
 224         }
 225
 226         return 0;
 227 }
 228
 229 bool batadv_check_management_packet(struct sk_buff *skb,
 230                                     struct batadv_hard_iface *hard_iface,
 231                                     int header_len)
 232 {
 233         struct ethhdr *ethhdr;
 234
 235         /* drop packet if it has not necessary minimum size */
 236         if (unlikely(!pskb_may_pull(skb, header_len)))
 237                 return false;
 238
 239         ethhdr = eth_hdr(skb);
 240
 241         /* packet with broadcast indication but unicast recipient */
 242         if (!is_broadcast_ether_addr(ethhdr->h_dest))
 243                 return false;
 244
 245         /* packet with broadcast sender address */
 246         if (is_broadcast_ether_addr(ethhdr->h_source))
 247                 return false;
 248
 249         /* create a copy of the skb, if needed, to modify it. */
 250         if (skb_cow(skb, 0) < 0)
 251                 return false;
 252
 253         /* keep skb linear */
 254         if (skb_linearize(skb) < 0)
 255                 return false;
 256
 257         return true;
 258 }
 259
 260 static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv,
 261                                       struct sk_buff *skb, size_t icmp_len)
 262 {
 263         struct batadv_hard_iface *primary_if = NULL;
 264         struct batadv_orig_node *orig_node = NULL;
 265         struct batadv_icmp_packet_rr *icmp_packet;
 266         int ret = NET_RX_DROP;
 267
 268         icmp_packet = (struct batadv_icmp_packet_rr *)skb->data;
 269
 270         /* add data to device queue */
 271         if (icmp_packet->msg_type != BATADV_ECHO_REQUEST) {
 272                 batadv_socket_receive_packet(icmp_packet, icmp_len);
 273                 goto out;
 274         }
 275
 276         primary_if = batadv_primary_if_get_selected(bat_priv);
 277         if (!primary_if)
 278                 goto out;
 279
 280         /* answer echo request (ping) */
 281         /* get routing information */
 282         orig_node = batadv_orig_hash_find(bat_priv, icmp_packet->orig);
 283         if (!orig_node)
 284                 goto out;
 285
 286         /* create a copy of the skb, if needed, to modify it. */
 287         if (skb_cow(skb, ETH_HLEN) < 0)
 288                 goto out;
 289
 290         icmp_packet = (struct batadv_icmp_packet_rr *)skb->data;
 291
 292         memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
 293         memcpy(icmp_packet->orig, primary_if->net_dev->dev_addr, ETH_ALEN);
 294         icmp_packet->msg_type = BATADV_ECHO_REPLY;
 295         icmp_packet->header.ttl = BATADV_TTL;
 296
 297         if (batadv_send_skb_to_orig(skb, orig_node, NULL) != NET_XMIT_DROP)
 298                 ret = NET_RX_SUCCESS;
 299
 300 out:
 301         if (primary_if)
 302                 batadv_hardif_free_ref(primary_if);
 303         if (orig_node)
 304                 batadv_orig_node_free_ref(orig_node);
 305         return ret;
 306 }
 307
 308 static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv,
 309                                          struct sk_buff *skb)
 310 {
 311         struct batadv_hard_iface *primary_if = NULL;
 312         struct batadv_orig_node *orig_node = NULL;
 313         struct batadv_icmp_packet *icmp_packet;
 314         int ret = NET_RX_DROP;
 315
 316         icmp_packet = (struct batadv_icmp_packet *)skb->data;
 317
 318         /* send TTL exceeded if packet is an echo request (traceroute) */
 319         if (icmp_packet->msg_type != BATADV_ECHO_REQUEST) {
 320                 pr_debug("Warning - can't forward icmp packet from %pM to %pM: ttl exceeded\n",
 321                          icmp_packet->orig, icmp_packet->dst);
 322                 goto out;
 323         }
 324
 325         primary_if = batadv_primary_if_get_selected(bat_priv);
 326         if (!primary_if)
 327                 goto out;
 328
 329         /* get routing information */
 330         orig_node = batadv_orig_hash_find(bat_priv, icmp_packet->orig);
 331         if (!orig_node)
 332                 goto out;
 333
 334         /* create a copy of the skb, if needed, to modify it. */
 335         if (skb_cow(skb, ETH_HLEN) < 0)
 336                 goto out;
 337
 338         icmp_packet = (struct batadv_icmp_packet *)skb->data;
 339
 340         memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
 341         memcpy(icmp_packet->orig, primary_if->net_dev->dev_addr, ETH_ALEN);
 342         icmp_packet->msg_type = BATADV_TTL_EXCEEDED;
 343         icmp_packet->header.ttl = BATADV_TTL;
 344
 345         if (batadv_send_skb_to_orig(skb, orig_node, NULL) != NET_XMIT_DROP)
 346                 ret = NET_RX_SUCCESS;
 347
 348 out:
 349         if (primary_if)
 350                 batadv_hardif_free_ref(primary_if);
 351         if (orig_node)
 352                 batadv_orig_node_free_ref(orig_node);
 353         return ret;
 354 }
 355
 356
 357 int batadv_recv_icmp_packet(struct sk_buff *skb,
 358                             struct batadv_hard_iface *recv_if)
 359 {
 360         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
 361         struct batadv_icmp_packet_rr *icmp_packet;
 362         struct ethhdr *ethhdr;
 363         struct batadv_orig_node *orig_node = NULL;
 364         int hdr_size = sizeof(struct batadv_icmp_packet);
 365         int ret = NET_RX_DROP;
 366
 367         /* we truncate all incoming icmp packets if they don't match our size */
 368         if (skb->len >= sizeof(struct batadv_icmp_packet_rr))
 369                 hdr_size = sizeof(struct batadv_icmp_packet_rr);
 370
 371         /* drop packet if it has not necessary minimum size */
 372         if (unlikely(!pskb_may_pull(skb, hdr_size)))
 373                 goto out;
 374
 375         ethhdr = eth_hdr(skb);
 376
 377         /* packet with unicast indication but broadcast recipient */
 378         if (is_broadcast_ether_addr(ethhdr->h_dest))
 379                 goto out;
 380
 381         /* packet with broadcast sender address */
 382         if (is_broadcast_ether_addr(ethhdr->h_source))
 383                 goto out;
 384
 385         /* not for me */
 386         if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest))
 387                 goto out;
 388
 389         icmp_packet = (struct batadv_icmp_packet_rr *)skb->data;
 390
 391         /* add record route information if not full */
 392         if ((hdr_size == sizeof(struct batadv_icmp_packet_rr)) &&
 393             (icmp_packet->rr_cur < BATADV_RR_LEN)) {
 394                 memcpy(&(icmp_packet->rr[icmp_packet->rr_cur]),
 395                        ethhdr->h_dest, ETH_ALEN);
 396                 icmp_packet->rr_cur++;
 397         }
 398
 399         /* packet for me */
 400         if (batadv_is_my_mac(bat_priv, icmp_packet->dst))
 401                 return batadv_recv_my_icmp_packet(bat_priv, skb, hdr_size);
 402
 403         /* TTL exceeded */
 404         if (icmp_packet->header.ttl < 2)
 405                 return batadv_recv_icmp_ttl_exceeded(bat_priv, skb);
 406
 407         /* get routing information */
 408         orig_node = batadv_orig_hash_find(bat_priv, icmp_packet->dst);
 409         if (!orig_node)
 410                 goto out;
 411
 412         /* create a copy of the skb, if needed, to modify it. */
 413         if (skb_cow(skb, ETH_HLEN) < 0)
 414                 goto out;
 415
 416         icmp_packet = (struct batadv_icmp_packet_rr *)skb->data;
 417
 418         /* decrement ttl */
 419         icmp_packet->header.ttl--;
 420
 421         /* route it */
 422         if (batadv_send_skb_to_orig(skb, orig_node, recv_if) != NET_XMIT_DROP)
 423                 ret = NET_RX_SUCCESS;
 424
 425 out:
 426         if (orig_node)
 427                 batadv_orig_node_free_ref(orig_node);
 428         return ret;
 429 }
 430
 431 /* In the bonding case, send the packets in a round
 432  * robin fashion over the remaining interfaces.
 433  *
 434  * This method rotates the bonding list and increases the
 435  * returned router's refcount.
 436  */
 437 static struct batadv_neigh_node *
 438 batadv_find_bond_router(struct batadv_orig_node *primary_orig,
 439                         const struct batadv_hard_iface *recv_if)
 440 {
 441         struct batadv_neigh_node *tmp_neigh_node;
 442         struct batadv_neigh_node *router = NULL, *first_candidate = NULL;
 443
 444         rcu_read_lock();
 445         list_for_each_entry_rcu(tmp_neigh_node, &primary_orig->bond_list,
 446                                 bonding_list) {
 447                 if (!first_candidate)
 448                         first_candidate = tmp_neigh_node;
 449
 450                 /* recv_if == NULL on the first node. */
 451                 if (tmp_neigh_node->if_incoming == recv_if)
 452                         continue;
 453
 454                 if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
 455                         continue;
 456
 457                 router = tmp_neigh_node;
 458                 break;
 459         }
 460
 461         /* use the first candidate if nothing was found. */
 462         if (!router && first_candidate &&
 463             atomic_inc_not_zero(&first_candidate->refcount))
 464                 router = first_candidate;
 465
 466         if (!router)
 467                 goto out;
 468
 469         /* selected should point to the next element
 470          * after the current router
 471          */
 472         spin_lock_bh(&primary_orig->neigh_list_lock);
 473         /* this is a list_move(), which unfortunately
 474          * does not exist as rcu version
 475          */
 476         list_del_rcu(&primary_orig->bond_list);
 477         list_add_rcu(&primary_orig->bond_list,
 478                      &router->bonding_list);
 479         spin_unlock_bh(&primary_orig->neigh_list_lock);
 480
 481 out:
 482         rcu_read_unlock();
 483         return router;
 484 }
 485
 486 /* Interface Alternating: Use the best of the
 487  * remaining candidates which are not using
 488  * this interface.
 489  *
 490  * Increases the returned router's refcount
 491  */
 492 static struct batadv_neigh_node *
 493 batadv_find_ifalter_router(struct batadv_orig_node *primary_orig,
 494                            const struct batadv_hard_iface *recv_if)
 495 {
 496         struct batadv_neigh_node *tmp_neigh_node;
 497         struct batadv_neigh_node *router = NULL, *first_candidate = NULL;
 498
 499         rcu_read_lock();
 500         list_for_each_entry_rcu(tmp_neigh_node, &primary_orig->bond_list,
 501                                 bonding_list) {
 502                 if (!first_candidate)
 503                         first_candidate = tmp_neigh_node;
 504
 505                 /* recv_if == NULL on the first node. */
 506                 if (tmp_neigh_node->if_incoming == recv_if)
 507                         continue;
 508
 509                 if (router && tmp_neigh_node->tq_avg <= router->tq_avg)
 510                         continue;
 511
 512                 if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
 513                         continue;
 514
 515                 /* decrement refcount of previously selected router */
 516                 if (router)
 517                         batadv_neigh_node_free_ref(router);
 518
 519                 /* we found a better router (or at least one valid router) */
 520                 router = tmp_neigh_node;
 521         }
 522
 523         /* use the first candidate if nothing was found. */
 524         if (!router && first_candidate &&
 525             atomic_inc_not_zero(&first_candidate->refcount))
 526                 router = first_candidate;
 527
 528         rcu_read_unlock();
 529         return router;
 530 }
 531
 532 /**
 533  * batadv_check_unicast_packet - Check for malformed unicast packets
 534  * @bat_priv: the bat priv with all the soft interface information
 535  * @skb: packet to check
 536  * @hdr_size: size of header to pull
 537  *
 538  * Check for short header and bad addresses in given packet. Returns negative
 539  * value when check fails and 0 otherwise. The negative value depends on the
 540  * reason: -ENODATA for bad header, -EBADR for broadcast destination or source,
 541  * and -EREMOTE for non-local (other host) destination.
 542  */
 543 static int batadv_check_unicast_packet(struct batadv_priv *bat_priv,
 544                                        struct sk_buff *skb, int hdr_size)
 545 {
 546         struct ethhdr *ethhdr;
 547
 548         /* drop packet if it has not necessary minimum size */
 549         if (unlikely(!pskb_may_pull(skb, hdr_size)))
 550                 return -ENODATA;
 551
 552         ethhdr = eth_hdr(skb);
 553
 554         /* packet with unicast indication but broadcast recipient */
 555         if (is_broadcast_ether_addr(ethhdr->h_dest))
 556                 return -EBADR;
 557
 558         /* packet with broadcast sender address */
 559         if (is_broadcast_ether_addr(ethhdr->h_source))
 560                 return -EBADR;
 561
 562         /* not for me */
 563         if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest))
 564                 return -EREMOTE;
 565
 566         return 0;
 567 }
 568
 569 int batadv_recv_tt_query(struct sk_buff *skb, struct batadv_hard_iface *recv_if)
 570 {
 571         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
 572         struct batadv_tt_query_packet *tt_query;
 573         uint16_t tt_size;
 574         int hdr_size = sizeof(*tt_query);
 575         char tt_flag;
 576         size_t packet_size;
 577
 578         if (batadv_check_unicast_packet(bat_priv, skb, hdr_size) < 0)
 579                 return NET_RX_DROP;
 580
 581         /* I could need to modify it */
 582         if (skb_cow(skb, sizeof(struct batadv_tt_query_packet)) < 0)
 583                 goto out;
 584
 585         tt_query = (struct batadv_tt_query_packet *)skb->data;
 586
 587         switch (tt_query->flags & BATADV_TT_QUERY_TYPE_MASK) {
 588         case BATADV_TT_REQUEST:
 589                 batadv_inc_counter(bat_priv, BATADV_CNT_TT_REQUEST_RX);
 590
 591                 /* If we cannot provide an answer the tt_request is
 592                  * forwarded
 593                  */
 594                 if (!batadv_send_tt_response(bat_priv, tt_query)) {
 595                         if (tt_query->flags & BATADV_TT_FULL_TABLE)
 596                                 tt_flag = 'F';
 597                         else
 598                                 tt_flag = '.';
 599
 600                         batadv_dbg(BATADV_DBG_TT, bat_priv,
 601                                    "Routing TT_REQUEST to %pM [%c]\n",
 602                                    tt_query->dst,
 603                                    tt_flag);
 604                         return batadv_route_unicast_packet(skb, recv_if);
 605                 }
 606                 break;
 607         case BATADV_TT_RESPONSE:
 608                 batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_RX);
 609
 610                 if (batadv_is_my_mac(bat_priv, tt_query->dst)) {
 611                         /* packet needs to be linearized to access the TT
 612                          * changes
 613                          */
 614                         if (skb_linearize(skb) < 0)
 615                                 goto out;
 616                         /* skb_linearize() possibly changed skb->data */
 617                         tt_query = (struct batadv_tt_query_packet *)skb->data;
 618
 619                         tt_size = batadv_tt_len(ntohs(tt_query->tt_data));
 620
 621                         /* Ensure we have all the claimed data */
 622                         packet_size = sizeof(struct batadv_tt_query_packet);
 623                         packet_size += tt_size;
 624                         if (unlikely(skb_headlen(skb) < packet_size))
 625                                 goto out;
 626
 627                         batadv_handle_tt_response(bat_priv, tt_query);
 628                 } else {
 629                         if (tt_query->flags & BATADV_TT_FULL_TABLE)
 630                                 tt_flag =  'F';
 631                         else
 632                                 tt_flag = '.';
 633                         batadv_dbg(BATADV_DBG_TT, bat_priv,
 634                                    "Routing TT_RESPONSE to %pM [%c]\n",
 635                                    tt_query->dst,
 636                                    tt_flag);
 637                         return batadv_route_unicast_packet(skb, recv_if);
 638                 }
 639                 break;
 640         }
 641
 642 out:
 643         /* returning NET_RX_DROP will make the caller function kfree the skb */
 644         return NET_RX_DROP;
 645 }
 646
 647 int batadv_recv_roam_adv(struct sk_buff *skb, struct batadv_hard_iface *recv_if)
 648 {
 649         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
 650         struct batadv_roam_adv_packet *roam_adv_packet;
 651         struct batadv_orig_node *orig_node;
 652
 653         if (batadv_check_unicast_packet(bat_priv, skb,
 654                                         sizeof(*roam_adv_packet)) < 0)
 655                 goto out;
 656
 657         batadv_inc_counter(bat_priv, BATADV_CNT_TT_ROAM_ADV_RX);
 658
 659         roam_adv_packet = (struct batadv_roam_adv_packet *)skb->data;
 660
 661         if (!batadv_is_my_mac(bat_priv, roam_adv_packet->dst))
 662                 return batadv_route_unicast_packet(skb, recv_if);
 663
 664         /* check if it is a backbone gateway. we don't accept
 665          * roaming advertisement from it, as it has the same
 666          * entries as we have.
 667          */
 668         if (batadv_bla_is_backbone_gw_orig(bat_priv, roam_adv_packet->src))
 669                 goto out;
 670
 671         orig_node = batadv_orig_hash_find(bat_priv, roam_adv_packet->src);
 672         if (!orig_node)
 673                 goto out;
 674
 675         batadv_dbg(BATADV_DBG_TT, bat_priv,
 676                    "Received ROAMING_ADV from %pM (client %pM)\n",
 677                    roam_adv_packet->src, roam_adv_packet->client);
 678
 679         batadv_tt_global_add(bat_priv, orig_node, roam_adv_packet->client,
 680                              BATADV_TT_CLIENT_ROAM,
 681                              atomic_read(&orig_node->last_ttvn) + 1);
 682
 683         batadv_orig_node_free_ref(orig_node);
 684 out:
 685         /* returning NET_RX_DROP will make the caller function kfree the skb */
 686         return NET_RX_DROP;
 687 }
 688
 689 /* find a suitable router for this originator, and use
 690  * bonding if possible. increases the found neighbors
 691  * refcount.
 692  */
 693 struct batadv_neigh_node *
 694 batadv_find_router(struct batadv_priv *bat_priv,
 695                    struct batadv_orig_node *orig_node,
 696                    const struct batadv_hard_iface *recv_if)
 697 {
 698         struct batadv_orig_node *primary_orig_node;
 699         struct batadv_orig_node *router_orig;
 700         struct batadv_neigh_node *router;
 701         static uint8_t zero_mac[ETH_ALEN] = {0, 0, 0, 0, 0, 0};
 702         int bonding_enabled;
 703         uint8_t *primary_addr;
 704
 705         if (!orig_node)
 706                 return NULL;
 707
 708         router = batadv_orig_node_get_router(orig_node);
 709         if (!router)
 710                 goto err;
 711
 712         /* without bonding, the first node should
 713          * always choose the default router.
 714          */
 715         bonding_enabled = atomic_read(&bat_priv->bonding);
 716
 717         rcu_read_lock();
 718         /* select default router to output */
 719         router_orig = router->orig_node;
 720         if (!router_orig)
 721                 goto err_unlock;
 722
 723         if ((!recv_if) && (!bonding_enabled))
 724                 goto return_router;
 725
 726         primary_addr = router_orig->primary_addr;
 727
 728         /* if we have something in the primary_addr, we can search
 729          * for a potential bonding candidate.
 730          */
 731         if (batadv_compare_eth(primary_addr, zero_mac))
 732                 goto return_router;
 733
 734         /* find the orig_node which has the primary interface. might
 735          * even be the same as our router_orig in many cases
 736          */
 737         if (batadv_compare_eth(primary_addr, router_orig->orig)) {
 738                 primary_orig_node = router_orig;
 739         } else {
 740                 primary_orig_node = batadv_orig_hash_find(bat_priv,
 741                                                           primary_addr);
 742                 if (!primary_orig_node)
 743                         goto return_router;
 744
 745                 batadv_orig_node_free_ref(primary_orig_node);
 746         }
 747
 748         /* with less than 2 candidates, we can't do any
 749          * bonding and prefer the original router.
 750          */
 751         if (atomic_read(&primary_orig_node->bond_candidates) < 2)
 752                 goto return_router;
 753
 754         /* all nodes between should choose a candidate which
 755          * is is not on the interface where the packet came
 756          * in.
 757          */
 758         batadv_neigh_node_free_ref(router);
 759
 760         if (bonding_enabled)
 761                 router = batadv_find_bond_router(primary_orig_node, recv_if);
 762         else
 763                 router = batadv_find_ifalter_router(primary_orig_node, recv_if);
 764
 765 return_router:
 766         if (router && router->if_incoming->if_status != BATADV_IF_ACTIVE)
 767                 goto err_unlock;
 768
 769         rcu_read_unlock();
 770         return router;
 771 err_unlock:
 772         rcu_read_unlock();
 773 err:
 774         if (router)
 775                 batadv_neigh_node_free_ref(router);
 776         return NULL;
 777 }
 778
 779 static int batadv_route_unicast_packet(struct sk_buff *skb,
 780                                        struct batadv_hard_iface *recv_if)
 781 {
 782         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
 783         struct batadv_orig_node *orig_node = NULL;
 784         struct batadv_neigh_node *neigh_node = NULL;
 785         struct batadv_unicast_packet *unicast_packet;
 786         struct ethhdr *ethhdr = eth_hdr(skb);
 787         int res, hdr_len, ret = NET_RX_DROP;
 788         struct sk_buff *new_skb;
 789
 790         unicast_packet = (struct batadv_unicast_packet *)skb->data;
 791
 792         /* TTL exceeded */
 793         if (unicast_packet->header.ttl < 2) {
 794                 pr_debug("Warning - can't forward unicast packet from %pM to %pM: ttl exceeded\n",
 795                          ethhdr->h_source, unicast_packet->dest);
 796                 goto out;
 797         }
 798
 799         /* get routing information */
 800         orig_node = batadv_orig_hash_find(bat_priv, unicast_packet->dest);
 801
 802         if (!orig_node)
 803                 goto out;
 804
 805         /* find_router() increases neigh_nodes refcount if found. */
 806         neigh_node = batadv_find_router(bat_priv, orig_node, recv_if);
 807
 808         if (!neigh_node)
 809                 goto out;
 810
 811         /* create a copy of the skb, if needed, to modify it. */
 812         if (skb_cow(skb, ETH_HLEN) < 0)
 813                 goto out;
 814
 815         unicast_packet = (struct batadv_unicast_packet *)skb->data;
 816
 817         if (unicast_packet->header.packet_type == BATADV_UNICAST &&
 818             atomic_read(&bat_priv->fragmentation) &&
 819             skb->len > neigh_node->if_incoming->net_dev->mtu) {
 820                 ret = batadv_frag_send_skb(skb, bat_priv,
 821                                            neigh_node->if_incoming,
 822                                            neigh_node->addr);
 823                 goto out;
 824         }
 825
 826         if (unicast_packet->header.packet_type == BATADV_UNICAST_FRAG &&
 827             batadv_frag_can_reassemble(skb,
 828                                        neigh_node->if_incoming->net_dev->mtu)) {
 829                 ret = batadv_frag_reassemble_skb(skb, bat_priv, &new_skb);
 830
 831                 if (ret == NET_RX_DROP)
 832                         goto out;
 833
 834                 /* packet was buffered for late merge */
 835                 if (!new_skb) {
 836                         ret = NET_RX_SUCCESS;
 837                         goto out;
 838                 }
 839
 840                 skb = new_skb;
 841                 unicast_packet = (struct batadv_unicast_packet *)skb->data;
 842         }
 843
 844         /* decrement ttl */
 845         unicast_packet->header.ttl--;
 846
 847         switch (unicast_packet->header.packet_type) {
 848         case BATADV_UNICAST_4ADDR:
 849                 hdr_len = sizeof(struct batadv_unicast_4addr_packet);
 850                 break;
 851         case BATADV_UNICAST:
 852                 hdr_len = sizeof(struct batadv_unicast_packet);
 853                 break;
 854         default:
 855                 /* other packet types not supported - yet */
 856                 hdr_len = -1;
 857                 break;
 858         }
 859
 860         if (hdr_len > 0)
 861                 batadv_skb_set_priority(skb, hdr_len);
 862
 863         res = batadv_send_skb_to_orig(skb, orig_node, recv_if);
 864
 865         /* translate transmit result into receive result */
 866         if (res == NET_XMIT_SUCCESS) {
 867                 /* skb was transmitted and consumed */
 868                 batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD);
 869                 batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES,
 870                                    skb->len + ETH_HLEN);
 871
 872                 ret = NET_RX_SUCCESS;
 873         } else if (res == NET_XMIT_POLICED) {
 874                 /* skb was buffered and consumed */
 875                 ret = NET_RX_SUCCESS;
 876         }
 877
 878 out:
 879         if (neigh_node)
 880                 batadv_neigh_node_free_ref(neigh_node);
 881         if (orig_node)
 882                 batadv_orig_node_free_ref(orig_node);
 883         return ret;
 884 }
 885
 886 /**
 887  * batadv_reroute_unicast_packet - update the unicast header for re-routing
 888  * @bat_priv: the bat priv with all the soft interface information
 889  * @unicast_packet: the unicast header to be updated
 890  * @dst_addr: the payload destination
 891  *
 892  * Search the translation table for dst_addr and update the unicast header with
 893  * the new corresponding information (originator address where the destination
 894  * client currently is and its known TTVN)
 895  *
 896  * Returns true if the packet header has been updated, false otherwise
 897  */
 898 static bool
 899 batadv_reroute_unicast_packet(struct batadv_priv *bat_priv,
 900                               struct batadv_unicast_packet *unicast_packet,
 901                               uint8_t *dst_addr)
 902 {
 903         struct batadv_orig_node *orig_node = NULL;
 904         struct batadv_hard_iface *primary_if = NULL;
 905         bool ret = false;
 906         uint8_t *orig_addr, orig_ttvn;
 907
 908         if (batadv_is_my_client(bat_priv, dst_addr)) {
 909                 primary_if = batadv_primary_if_get_selected(bat_priv);
 910                 if (!primary_if)
 911                         goto out;
 912                 orig_addr = primary_if->net_dev->dev_addr;
 913                 orig_ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn);
 914         } else {
 915                 orig_node = batadv_transtable_search(bat_priv, NULL, dst_addr);
 916                 if (!orig_node)
 917                         goto out;
 918
 919                 if (batadv_compare_eth(orig_node->orig, unicast_packet->dest))
 920                         goto out;
 921
 922                 orig_addr = orig_node->orig;
 923                 orig_ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
 924         }
 925
 926         /* update the packet header */
 927         memcpy(unicast_packet->dest, orig_addr, ETH_ALEN);
 928         unicast_packet->ttvn = orig_ttvn;
 929
 930         ret = true;
 931 out:
 932         if (primary_if)
 933                 batadv_hardif_free_ref(primary_if);
 934         if (orig_node)
 935                 batadv_orig_node_free_ref(orig_node);
 936
 937         return ret;
 938 }
 939
 940 static int batadv_check_unicast_ttvn(struct batadv_priv *bat_priv,
 941                                      struct sk_buff *skb, int hdr_len) {
 942         uint8_t curr_ttvn, old_ttvn;
 943         struct batadv_orig_node *orig_node;
 944         struct ethhdr *ethhdr;
 945         struct batadv_hard_iface *primary_if;
 946         struct batadv_unicast_packet *unicast_packet;
 947         int is_old_ttvn;
 948
 949         /* check if there is enough data before accessing it */
 950         if (pskb_may_pull(skb, hdr_len + ETH_HLEN) < 0)
 951                 return 0;
 952
 953         /* create a copy of the skb (in case of for re-routing) to modify it. */
 954         if (skb_cow(skb, sizeof(*unicast_packet)) < 0)
 955                 return 0;
 956
 957         unicast_packet = (struct batadv_unicast_packet *)skb->data;
 958         ethhdr = (struct ethhdr *)(skb->data + hdr_len);
 959
 960         /* check if the destination client was served by this node and it is now
 961          * roaming. In this case, it means that the node has got a ROAM_ADV
 962          * message and that it knows the new destination in the mesh to re-route
 963          * the packet to
 964          */
 965         if (batadv_tt_local_client_is_roaming(bat_priv, ethhdr->h_dest)) {
 966                 if (batadv_reroute_unicast_packet(bat_priv, unicast_packet,
 967                                                   ethhdr->h_dest))
 968                         net_ratelimited_function(batadv_dbg, BATADV_DBG_TT,
 969                                                  bat_priv,
 970                                                  "Rerouting unicast packet to %pM (dst=%pM): Local Roaming\n",
 971                                                  unicast_packet->dest,
 972                                                  ethhdr->h_dest);
 973                 /* at this point the mesh destination should have been
 974                  * substituted with the originator address found in the global
 975                  * table. If not, let the packet go untouched anyway because
 976                  * there is nothing the node can do
 977                  */
 978                 return 1;
 979         }
 980
 981         /* retrieve the TTVN known by this node for the packet destination. This
 982          * value is used later to check if the node which sent (or re-routed
 983          * last time) the packet had an updated information or not
 984          */
 985         curr_ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn);
 986         if (!batadv_is_my_mac(bat_priv, unicast_packet->dest)) {
 987                 orig_node = batadv_orig_hash_find(bat_priv,
 988                                                   unicast_packet->dest);
 989                 /* if it is not possible to find the orig_node representing the
 990                  * destination, the packet can immediately be dropped as it will
 991                  * not be possible to deliver it
 992                  */
 993                 if (!orig_node)
 994                         return 0;
 995
 996                 curr_ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
 997                 batadv_orig_node_free_ref(orig_node);
 998         }
 999
1000         /* check if the TTVN contained in the packet is fresher than what the
1001          * node knows
1002          */
1003         is_old_ttvn = batadv_seq_before(unicast_packet->ttvn, curr_ttvn);
1004         if (!is_old_ttvn)
1005                 return 1;
1006
1007         old_ttvn = unicast_packet->ttvn;
1008         /* the packet was forged based on outdated network information. Its
1009          * destination can possibly be updated and forwarded towards the new
1010          * target host
1011          */
1012         if (batadv_reroute_unicast_packet(bat_priv, unicast_packet,
1013                                           ethhdr->h_dest)) {
1014                 net_ratelimited_function(batadv_dbg, BATADV_DBG_TT, bat_priv,
1015                                          "Rerouting unicast packet to %pM (dst=%pM): TTVN mismatch old_ttvn=%u new_ttvn=%u\n",
1016                                          unicast_packet->dest, ethhdr->h_dest,
1017                                          old_ttvn, curr_ttvn);
1018                 return 1;
1019         }
1020
1021         /* the packet has not been re-routed: either the destination is
1022          * currently served by this node or there is no destination at all and
1023          * it is possible to drop the packet
1024          */
1025         if (!batadv_is_my_client(bat_priv, ethhdr->h_dest))
1026                 return 0;
1027
1028         /* update the header in order to let the packet be delivered to this
1029          * node's soft interface
1030          */
1031         primary_if = batadv_primary_if_get_selected(bat_priv);
1032         if (!primary_if)
1033                 return 0;
1034
1035         memcpy(unicast_packet->dest, primary_if->net_dev->dev_addr, ETH_ALEN);
1036
1037         batadv_hardif_free_ref(primary_if);
1038
1039         unicast_packet->ttvn = curr_ttvn;
1040
1041         return 1;
1042 }
1043
1044 int batadv_recv_unicast_packet(struct sk_buff *skb,
1045                                struct batadv_hard_iface *recv_if)
1046 {
1047         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1048         struct batadv_unicast_packet *unicast_packet;
1049         struct batadv_unicast_4addr_packet *unicast_4addr_packet;
1050         uint8_t *orig_addr;
1051         struct batadv_orig_node *orig_node = NULL;
1052         int check, hdr_size = sizeof(*unicast_packet);
1053         bool is4addr;
1054
1055         unicast_packet = (struct batadv_unicast_packet *)skb->data;
1056         unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
1057
1058         is4addr = unicast_packet->header.packet_type == BATADV_UNICAST_4ADDR;
1059         /* the caller function should have already pulled 2 bytes */
1060         if (is4addr)
1061                 hdr_size = sizeof(*unicast_4addr_packet);
1062
1063         /* function returns -EREMOTE for promiscuous packets */
1064         check = batadv_check_unicast_packet(bat_priv, skb, hdr_size);
1065
1066         /* Even though the packet is not for us, we might save it to use for
1067          * decoding a later received coded packet
1068          */
1069         if (check == -EREMOTE)
1070                 batadv_nc_skb_store_sniffed_unicast(bat_priv, skb);
1071
1072         if (check < 0)
1073                 return NET_RX_DROP;
1074         if (!batadv_check_unicast_ttvn(bat_priv, skb, hdr_size))
1075                 return NET_RX_DROP;
1076
1077         /* packet for me */
1078         if (batadv_is_my_mac(bat_priv, unicast_packet->dest)) {
1079                 if (is4addr) {
1080                         batadv_dat_inc_counter(bat_priv,
1081                                                unicast_4addr_packet->subtype);
1082                         orig_addr = unicast_4addr_packet->src;
1083                         orig_node = batadv_orig_hash_find(bat_priv, orig_addr);
1084                 }
1085
1086                 if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb,
1087                                                           hdr_size))
1088                         goto rx_success;
1089                 if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb,
1090                                                         hdr_size))
1091                         goto rx_success;
1092
1093                 batadv_interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size,
1094                                     orig_node);
1095
1096 rx_success:
1097                 if (orig_node)
1098                         batadv_orig_node_free_ref(orig_node);
1099
1100                 return NET_RX_SUCCESS;
1101         }
1102
1103         return batadv_route_unicast_packet(skb, recv_if);
1104 }
1105
1106 int batadv_recv_ucast_frag_packet(struct sk_buff *skb,
1107                                   struct batadv_hard_iface *recv_if)
1108 {
1109         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1110         struct batadv_unicast_frag_packet *unicast_packet;
1111         int hdr_size = sizeof(*unicast_packet);
1112         struct sk_buff *new_skb = NULL;
1113         int ret;
1114
1115         if (batadv_check_unicast_packet(bat_priv, skb, hdr_size) < 0)
1116                 return NET_RX_DROP;
1117
1118         if (!batadv_check_unicast_ttvn(bat_priv, skb, hdr_size))
1119                 return NET_RX_DROP;
1120
1121         unicast_packet = (struct batadv_unicast_frag_packet *)skb->data;
1122
1123         /* packet for me */
1124         if (batadv_is_my_mac(bat_priv, unicast_packet->dest)) {
1125                 ret = batadv_frag_reassemble_skb(skb, bat_priv, &new_skb);
1126
1127                 if (ret == NET_RX_DROP)
1128                         return NET_RX_DROP;
1129
1130                 /* packet was buffered for late merge */
1131                 if (!new_skb)
1132                         return NET_RX_SUCCESS;
1133
1134                 if (batadv_dat_snoop_incoming_arp_request(bat_priv, new_skb,
1135                                                           hdr_size))
1136                         goto rx_success;
1137                 if (batadv_dat_snoop_incoming_arp_reply(bat_priv, new_skb,
1138                                                         hdr_size))
1139                         goto rx_success;
1140
1141                 batadv_interface_rx(recv_if->soft_iface, new_skb, recv_if,
1142                                     sizeof(struct batadv_unicast_packet), NULL);
1143
1144 rx_success:
1145                 return NET_RX_SUCCESS;
1146         }
1147
1148         return batadv_route_unicast_packet(skb, recv_if);
1149 }
1150
1151
1152 int batadv_recv_bcast_packet(struct sk_buff *skb,
1153                              struct batadv_hard_iface *recv_if)
1154 {
1155         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1156         struct batadv_orig_node *orig_node = NULL;
1157         struct batadv_bcast_packet *bcast_packet;
1158         struct ethhdr *ethhdr;
1159         int hdr_size = sizeof(*bcast_packet);
1160         int ret = NET_RX_DROP;
1161         int32_t seq_diff;
1162
1163         /* drop packet if it has not necessary minimum size */
1164         if (unlikely(!pskb_may_pull(skb, hdr_size)))
1165                 goto out;
1166
1167         ethhdr = eth_hdr(skb);
1168
1169         /* packet with broadcast indication but unicast recipient */
1170         if (!is_broadcast_ether_addr(ethhdr->h_dest))
1171                 goto out;
1172
1173         /* packet with broadcast sender address */
1174         if (is_broadcast_ether_addr(ethhdr->h_source))
1175                 goto out;
1176
1177         /* ignore broadcasts sent by myself */
1178         if (batadv_is_my_mac(bat_priv, ethhdr->h_source))
1179                 goto out;
1180
1181         bcast_packet = (struct batadv_bcast_packet *)skb->data;
1182
1183         /* ignore broadcasts originated by myself */
1184         if (batadv_is_my_mac(bat_priv, bcast_packet->orig))
1185                 goto out;
1186
1187         if (bcast_packet->header.ttl < 2)
1188                 goto out;
1189
1190         orig_node = batadv_orig_hash_find(bat_priv, bcast_packet->orig);
1191
1192         if (!orig_node)
1193                 goto out;
1194
1195         spin_lock_bh(&orig_node->bcast_seqno_lock);
1196
1197         /* check whether the packet is a duplicate */
1198         if (batadv_test_bit(orig_node->bcast_bits, orig_node->last_bcast_seqno,
1199                             ntohl(bcast_packet->seqno)))
1200                 goto spin_unlock;
1201
1202         seq_diff = ntohl(bcast_packet->seqno) - orig_node->last_bcast_seqno;
1203
1204         /* check whether the packet is old and the host just restarted. */
1205         if (batadv_window_protected(bat_priv, seq_diff,
1206                                     &orig_node->bcast_seqno_reset))
1207                 goto spin_unlock;
1208
1209         /* mark broadcast in flood history, update window position
1210          * if required.
1211          */
1212         if (batadv_bit_get_packet(bat_priv, orig_node->bcast_bits, seq_diff, 1))
1213                 orig_node->last_bcast_seqno = ntohl(bcast_packet->seqno);
1214
1215         spin_unlock_bh(&orig_node->bcast_seqno_lock);
1216
1217         /* check whether this has been sent by another originator before */
1218         if (batadv_bla_check_bcast_duplist(bat_priv, skb))
1219                 goto out;
1220
1221         batadv_skb_set_priority(skb, sizeof(struct batadv_bcast_packet));
1222
1223         /* rebroadcast packet */
1224         batadv_add_bcast_packet_to_list(bat_priv, skb, 1);
1225
1226         /* don't hand the broadcast up if it is from an originator
1227          * from the same backbone.
1228          */
1229         if (batadv_bla_is_backbone_gw(skb, orig_node, hdr_size))
1230                 goto out;
1231
1232         if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb, hdr_size))
1233                 goto rx_success;
1234         if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb, hdr_size))
1235                 goto rx_success;
1236
1237         /* broadcast for me */
1238         batadv_interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size,
1239                             orig_node);
1240
1241 rx_success:
1242         ret = NET_RX_SUCCESS;
1243         goto out;
1244
1245 spin_unlock:
1246         spin_unlock_bh(&orig_node->bcast_seqno_lock);
1247 out:
1248         if (orig_node)
1249                 batadv_orig_node_free_ref(orig_node);
1250         return ret;
1251 }
1252
1253 int batadv_recv_vis_packet(struct sk_buff *skb,
1254                            struct batadv_hard_iface *recv_if)
1255 {
1256         struct batadv_vis_packet *vis_packet;
1257         struct ethhdr *ethhdr;
1258         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1259         int hdr_size = sizeof(*vis_packet);
1260
1261         /* keep skb linear */
1262         if (skb_linearize(skb) < 0)
1263                 return NET_RX_DROP;
1264
1265         if (unlikely(!pskb_may_pull(skb, hdr_size)))
1266                 return NET_RX_DROP;
1267
1268         vis_packet = (struct batadv_vis_packet *)skb->data;
1269         ethhdr = eth_hdr(skb);
1270
1271         /* not for me */
1272         if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest))
1273                 return NET_RX_DROP;
1274
1275         /* ignore own packets */
1276         if (batadv_is_my_mac(bat_priv, vis_packet->vis_orig))
1277                 return NET_RX_DROP;
1278
1279         if (batadv_is_my_mac(bat_priv, vis_packet->sender_orig))
1280                 return NET_RX_DROP;
1281
1282         switch (vis_packet->vis_type) {
1283         case BATADV_VIS_TYPE_SERVER_SYNC:
1284                 batadv_receive_server_sync_packet(bat_priv, vis_packet,
1285                                                   skb_headlen(skb));
1286                 break;
1287
1288         case BATADV_VIS_TYPE_CLIENT_UPDATE:
1289                 batadv_receive_client_update_packet(bat_priv, vis_packet,
1290                                                     skb_headlen(skb));
1291                 break;
1292
1293         default:        /* ignore unknown packet */
1294                 break;
1295         }
1296
1297         /* We take a copy of the data in the packet, so we should
1298          * always free the skbuf.
1299          */
1300         return NET_RX_DROP;
1301 }