net/batman-adv/routing.c

   1 /*
   2  * Copyright (C) 2007-2011 B.A.T.M.A.N. contributors:
   3  *
   4  * Marek Lindner, Simon Wunderlich
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of version 2 of the GNU General Public
   8  * License as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  18  * 02110-1301, USA
  19  *
  20  */
  21
  22 #include "main.h"
  23 #include "routing.h"
  24 #include "send.h"
  25 #include "hash.h"
  26 #include "soft-interface.h"
  27 #include "hard-interface.h"
  28 #include "icmp_socket.h"
  29 #include "translation-table.h"
  30 #include "originator.h"
  31 #include "ring_buffer.h"
  32 #include "vis.h"
  33 #include "aggregation.h"
  34 #include "gateway_common.h"
  35 #include "gateway_client.h"
  36 #include "unicast.h"
  37
  38 void slide_own_bcast_window(struct batman_if *batman_if)
  39 {
  40         struct bat_priv *bat_priv = netdev_priv(batman_if->soft_iface);
  41         struct hashtable_t *hash = bat_priv->orig_hash;
  42         struct hlist_node *node;
  43         struct hlist_head *head;
  44         struct orig_node *orig_node;
  45         unsigned long *word;
  46         int i;
  47         size_t word_index;
  48
  49         spin_lock_bh(&bat_priv->orig_hash_lock);
  50
  51         for (i = 0; i < hash->size; i++) {
  52                 head = &hash->table[i];
  53
  54                 rcu_read_lock();
  55                 hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
  56                         spin_lock_bh(&orig_node->ogm_cnt_lock);
  57                         word_index = batman_if->if_num * NUM_WORDS;
  58                         word = &(orig_node->bcast_own[word_index]);
  59
  60                         bit_get_packet(bat_priv, word, 1, 0);
  61                         orig_node->bcast_own_sum[batman_if->if_num] =
  62                                 bit_packet_count(word);
  63                         spin_unlock_bh(&orig_node->ogm_cnt_lock);
  64                 }
  65                 rcu_read_unlock();
  66         }
  67
  68         spin_unlock_bh(&bat_priv->orig_hash_lock);
  69 }
  70
  71 static void update_HNA(struct bat_priv *bat_priv, struct orig_node *orig_node,
  72                        unsigned char *hna_buff, int hna_buff_len)
  73 {
  74         if ((hna_buff_len != orig_node->hna_buff_len) ||
  75             ((hna_buff_len > 0) &&
  76              (orig_node->hna_buff_len > 0) &&
  77              (memcmp(orig_node->hna_buff, hna_buff, hna_buff_len) != 0))) {
  78
  79                 if (orig_node->hna_buff_len > 0)
  80                         hna_global_del_orig(bat_priv, orig_node,
  81                                             "originator changed hna");
  82
  83                 if ((hna_buff_len > 0) && (hna_buff))
  84                         hna_global_add_orig(bat_priv, orig_node,
  85                                             hna_buff, hna_buff_len);
  86         }
  87 }
  88
  89 static void update_route(struct bat_priv *bat_priv,
  90                          struct orig_node *orig_node,
  91                          struct neigh_node *neigh_node,
  92                          unsigned char *hna_buff, int hna_buff_len)
  93 {
  94         struct neigh_node *neigh_node_tmp;
  95
  96         /* route deleted */
  97         if ((orig_node->router) && (!neigh_node)) {
  98
  99                 bat_dbg(DBG_ROUTES, bat_priv, "Deleting route towards: %pM\n",
 100                         orig_node->orig);
 101                 hna_global_del_orig(bat_priv, orig_node,
 102                                     "originator timed out");
 103
 104                 /* route added */
 105         } else if ((!orig_node->router) && (neigh_node)) {
 106
 107                 bat_dbg(DBG_ROUTES, bat_priv,
 108                         "Adding route towards: %pM (via %pM)\n",
 109                         orig_node->orig, neigh_node->addr);
 110                 hna_global_add_orig(bat_priv, orig_node,
 111                                     hna_buff, hna_buff_len);
 112
 113                 /* route changed */
 114         } else {
 115                 bat_dbg(DBG_ROUTES, bat_priv,
 116                         "Changing route towards: %pM "
 117                         "(now via %pM - was via %pM)\n",
 118                         orig_node->orig, neigh_node->addr,
 119                         orig_node->router->addr);
 120         }
 121
 122         if (neigh_node && !atomic_inc_not_zero(&neigh_node->refcount))
 123                 neigh_node = NULL;
 124         neigh_node_tmp = orig_node->router;
 125         orig_node->router = neigh_node;
 126         if (neigh_node_tmp)
 127                 neigh_node_free_ref(neigh_node_tmp);
 128 }
 129
 130
 131 void update_routes(struct bat_priv *bat_priv, struct orig_node *orig_node,
 132                    struct neigh_node *neigh_node, unsigned char *hna_buff,
 133                    int hna_buff_len)
 134 {
 135
 136         if (!orig_node)
 137                 return;
 138
 139         if (orig_node->router != neigh_node)
 140                 update_route(bat_priv, orig_node, neigh_node,
 141                              hna_buff, hna_buff_len);
 142         /* may be just HNA changed */
 143         else
 144                 update_HNA(bat_priv, orig_node, hna_buff, hna_buff_len);
 145 }
 146
 147 static int is_bidirectional_neigh(struct orig_node *orig_node,
 148                                 struct orig_node *orig_neigh_node,
 149                                 struct batman_packet *batman_packet,
 150                                 struct batman_if *if_incoming)
 151 {
 152         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 153         struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 154         struct hlist_node *node;
 155         unsigned char total_count;
 156         uint8_t orig_eq_count, neigh_rq_count, tq_own;
 157         int tq_asym_penalty, ret = 0;
 158
 159         if (orig_node == orig_neigh_node) {
 160                 rcu_read_lock();
 161                 hlist_for_each_entry_rcu(tmp_neigh_node, node,
 162                                          &orig_node->neigh_list, list) {
 163
 164                         if (compare_eth(tmp_neigh_node->addr,
 165                                         orig_neigh_node->orig) &&
 166                             (tmp_neigh_node->if_incoming == if_incoming))
 167                                 neigh_node = tmp_neigh_node;
 168                 }
 169
 170                 if (!neigh_node)
 171                         neigh_node = create_neighbor(orig_node,
 172                                                      orig_neigh_node,
 173                                                      orig_neigh_node->orig,
 174                                                      if_incoming);
 175                 /* create_neighbor failed, return 0 */
 176                 if (!neigh_node)
 177                         goto unlock;
 178
 179                 if (!atomic_inc_not_zero(&neigh_node->refcount)) {
 180                         neigh_node = NULL;
 181                         goto unlock;
 182                 }
 183
 184                 rcu_read_unlock();
 185
 186                 neigh_node->last_valid = jiffies;
 187         } else {
 188                 /* find packet count of corresponding one hop neighbor */
 189                 rcu_read_lock();
 190                 hlist_for_each_entry_rcu(tmp_neigh_node, node,
 191                                          &orig_neigh_node->neigh_list, list) {
 192
 193                         if (compare_eth(tmp_neigh_node->addr,
 194                                         orig_neigh_node->orig) &&
 195                             (tmp_neigh_node->if_incoming == if_incoming))
 196                                 neigh_node = tmp_neigh_node;
 197                 }
 198
 199                 if (!neigh_node)
 200                         neigh_node = create_neighbor(orig_neigh_node,
 201                                                      orig_neigh_node,
 202                                                      orig_neigh_node->orig,
 203                                                      if_incoming);
 204                 /* create_neighbor failed, return 0 */
 205                 if (!neigh_node)
 206                         goto unlock;
 207
 208                 if (!atomic_inc_not_zero(&neigh_node->refcount)) {
 209                         neigh_node = NULL;
 210                         goto unlock;
 211                 }
 212
 213                 rcu_read_unlock();
 214         }
 215
 216         orig_node->last_valid = jiffies;
 217
 218         spin_lock_bh(&orig_node->ogm_cnt_lock);
 219         orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num];
 220         neigh_rq_count = neigh_node->real_packet_count;
 221         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 222
 223         /* pay attention to not get a value bigger than 100 % */
 224         total_count = (orig_eq_count > neigh_rq_count ?
 225                        neigh_rq_count : orig_eq_count);
 226
 227         /* if we have too few packets (too less data) we set tq_own to zero */
 228         /* if we receive too few packets it is not considered bidirectional */
 229         if ((total_count < TQ_LOCAL_BIDRECT_SEND_MINIMUM) ||
 230             (neigh_rq_count < TQ_LOCAL_BIDRECT_RECV_MINIMUM))
 231                 tq_own = 0;
 232         else
 233                 /* neigh_node->real_packet_count is never zero as we
 234                  * only purge old information when getting new
 235                  * information */
 236                 tq_own = (TQ_MAX_VALUE * total_count) / neigh_rq_count;
 237
 238         /*
 239          * 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
 240          * affect the nearly-symmetric links only a little, but
 241          * punishes asymmetric links more.  This will give a value
 242          * between 0 and TQ_MAX_VALUE
 243          */
 244         tq_asym_penalty = TQ_MAX_VALUE - (TQ_MAX_VALUE *
 245                                 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) *
 246                                 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) *
 247                                 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count)) /
 248                                         (TQ_LOCAL_WINDOW_SIZE *
 249                                          TQ_LOCAL_WINDOW_SIZE *
 250                                          TQ_LOCAL_WINDOW_SIZE);
 251
 252         batman_packet->tq = ((batman_packet->tq * tq_own * tq_asym_penalty) /
 253                                                 (TQ_MAX_VALUE * TQ_MAX_VALUE));
 254
 255         bat_dbg(DBG_BATMAN, bat_priv,
 256                 "bidirectional: "
 257                 "orig = %-15pM neigh = %-15pM => own_bcast = %2i, "
 258                 "real recv = %2i, local tq: %3i, asym_penalty: %3i, "
 259                 "total tq: %3i\n",
 260                 orig_node->orig, orig_neigh_node->orig, total_count,
 261                 neigh_rq_count, tq_own, tq_asym_penalty, batman_packet->tq);
 262
 263         /* if link has the minimum required transmission quality
 264          * consider it bidirectional */
 265         if (batman_packet->tq >= TQ_TOTAL_BIDRECT_LIMIT)
 266                 ret = 1;
 267
 268         goto out;
 269
 270 unlock:
 271         rcu_read_unlock();
 272 out:
 273         if (neigh_node)
 274                 neigh_node_free_ref(neigh_node);
 275         return ret;
 276 }
 277
 278 /* caller must hold the neigh_list_lock */
 279 void bonding_candidate_del(struct orig_node *orig_node,
 280                            struct neigh_node *neigh_node)
 281 {
 282         /* this neighbor is not part of our candidate list */
 283         if (list_empty(&neigh_node->bonding_list))
 284                 goto out;
 285
 286         list_del_rcu(&neigh_node->bonding_list);
 287         INIT_LIST_HEAD(&neigh_node->bonding_list);
 288         neigh_node_free_ref(neigh_node);
 289         atomic_dec(&orig_node->bond_candidates);
 290
 291 out:
 292         return;
 293 }
 294
 295 static void bonding_candidate_add(struct orig_node *orig_node,
 296                                   struct neigh_node *neigh_node)
 297 {
 298         struct hlist_node *node;
 299         struct neigh_node *tmp_neigh_node;
 300         uint8_t best_tq, interference_candidate = 0;
 301
 302         spin_lock_bh(&orig_node->neigh_list_lock);
 303
 304         /* only consider if it has the same primary address ...  */
 305         if (!compare_eth(orig_node->orig,
 306                          neigh_node->orig_node->primary_addr))
 307                 goto candidate_del;
 308
 309         if (!orig_node->router)
 310                 goto candidate_del;
 311
 312         best_tq = orig_node->router->tq_avg;
 313
 314         /* ... and is good enough to be considered */
 315         if (neigh_node->tq_avg < best_tq - BONDING_TQ_THRESHOLD)
 316                 goto candidate_del;
 317
 318         /**
 319          * check if we have another candidate with the same mac address or
 320          * interface. If we do, we won't select this candidate because of
 321          * possible interference.
 322          */
 323         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 324                                  &orig_node->neigh_list, list) {
 325
 326                 if (tmp_neigh_node == neigh_node)
 327                         continue;
 328
 329                 /* we only care if the other candidate is even
 330                 * considered as candidate. */
 331                 if (list_empty(&tmp_neigh_node->bonding_list))
 332                         continue;
 333
 334                 if ((neigh_node->if_incoming == tmp_neigh_node->if_incoming) ||
 335                     (compare_eth(neigh_node->addr, tmp_neigh_node->addr))) {
 336                         interference_candidate = 1;
 337                         break;
 338                 }
 339         }
 340
 341         /* don't care further if it is an interference candidate */
 342         if (interference_candidate)
 343                 goto candidate_del;
 344
 345         /* this neighbor already is part of our candidate list */
 346         if (!list_empty(&neigh_node->bonding_list))
 347                 goto out;
 348
 349         if (!atomic_inc_not_zero(&neigh_node->refcount))
 350                 goto out;
 351
 352         list_add_rcu(&neigh_node->bonding_list, &orig_node->bond_list);
 353         atomic_inc(&orig_node->bond_candidates);
 354         goto out;
 355
 356 candidate_del:
 357         bonding_candidate_del(orig_node, neigh_node);
 358
 359 out:
 360         spin_unlock_bh(&orig_node->neigh_list_lock);
 361         return;
 362 }
 363
 364 /* copy primary address for bonding */
 365 static void bonding_save_primary(struct orig_node *orig_node,
 366                                  struct orig_node *orig_neigh_node,
 367                                  struct batman_packet *batman_packet)
 368 {
 369         if (!(batman_packet->flags & PRIMARIES_FIRST_HOP))
 370                 return;
 371
 372         memcpy(orig_neigh_node->primary_addr, orig_node->orig, ETH_ALEN);
 373 }
 374
 375 static void update_orig(struct bat_priv *bat_priv,
 376                         struct orig_node *orig_node,
 377                         struct ethhdr *ethhdr,
 378                         struct batman_packet *batman_packet,
 379                         struct batman_if *if_incoming,
 380                         unsigned char *hna_buff, int hna_buff_len,
 381                         char is_duplicate)
 382 {
 383         struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 384         struct orig_node *orig_node_tmp;
 385         struct hlist_node *node;
 386         int tmp_hna_buff_len;
 387         uint8_t bcast_own_sum_orig, bcast_own_sum_neigh;
 388
 389         bat_dbg(DBG_BATMAN, bat_priv, "update_originator(): "
 390                 "Searching and updating originator entry of received packet\n");
 391
 392         rcu_read_lock();
 393         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 394                                  &orig_node->neigh_list, list) {
 395                 if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) &&
 396                     (tmp_neigh_node->if_incoming == if_incoming) &&
 397                      atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
 398                         if (neigh_node)
 399                                 neigh_node_free_ref(neigh_node);
 400                         neigh_node = tmp_neigh_node;
 401                         continue;
 402                 }
 403
 404                 if (is_duplicate)
 405                         continue;
 406
 407                 ring_buffer_set(tmp_neigh_node->tq_recv,
 408                                 &tmp_neigh_node->tq_index, 0);
 409                 tmp_neigh_node->tq_avg =
 410                         ring_buffer_avg(tmp_neigh_node->tq_recv);
 411         }
 412
 413         if (!neigh_node) {
 414                 struct orig_node *orig_tmp;
 415
 416                 orig_tmp = get_orig_node(bat_priv, ethhdr->h_source);
 417                 if (!orig_tmp)
 418                         goto unlock;
 419
 420                 neigh_node = create_neighbor(orig_node, orig_tmp,
 421                                              ethhdr->h_source, if_incoming);
 422
 423                 orig_node_free_ref(orig_tmp);
 424                 if (!neigh_node)
 425                         goto unlock;
 426
 427                 if (!atomic_inc_not_zero(&neigh_node->refcount)) {
 428                         neigh_node = NULL;
 429                         goto unlock;
 430                 }
 431         } else
 432                 bat_dbg(DBG_BATMAN, bat_priv,
 433                         "Updating existing last-hop neighbor of originator\n");
 434
 435         rcu_read_unlock();
 436
 437         orig_node->flags = batman_packet->flags;
 438         neigh_node->last_valid = jiffies;
 439
 440         ring_buffer_set(neigh_node->tq_recv,
 441                         &neigh_node->tq_index,
 442                         batman_packet->tq);
 443         neigh_node->tq_avg = ring_buffer_avg(neigh_node->tq_recv);
 444
 445         if (!is_duplicate) {
 446                 orig_node->last_ttl = batman_packet->ttl;
 447                 neigh_node->last_ttl = batman_packet->ttl;
 448         }
 449
 450         bonding_candidate_add(orig_node, neigh_node);
 451
 452         tmp_hna_buff_len = (hna_buff_len > batman_packet->num_hna * ETH_ALEN ?
 453                             batman_packet->num_hna * ETH_ALEN : hna_buff_len);
 454
 455         /* if this neighbor already is our next hop there is nothing
 456          * to change */
 457         if (orig_node->router == neigh_node)
 458                 goto update_hna;
 459
 460         /* if this neighbor does not offer a better TQ we won't consider it */
 461         if ((orig_node->router) &&
 462             (orig_node->router->tq_avg > neigh_node->tq_avg))
 463                 goto update_hna;
 464
 465         /* if the TQ is the same and the link not more symetric we
 466          * won't consider it either */
 467         if ((orig_node->router) &&
 468              (neigh_node->tq_avg == orig_node->router->tq_avg)) {
 469                 orig_node_tmp = orig_node->router->orig_node;
 470                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 471                 bcast_own_sum_orig =
 472                         orig_node_tmp->bcast_own_sum[if_incoming->if_num];
 473                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 474
 475                 orig_node_tmp = neigh_node->orig_node;
 476                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
 477                 bcast_own_sum_neigh =
 478                         orig_node_tmp->bcast_own_sum[if_incoming->if_num];
 479                 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
 480
 481                 if (bcast_own_sum_orig >= bcast_own_sum_neigh)
 482                         goto update_hna;
 483         }
 484
 485         update_routes(bat_priv, orig_node, neigh_node,
 486                       hna_buff, tmp_hna_buff_len);
 487         goto update_gw;
 488
 489 update_hna:
 490         update_routes(bat_priv, orig_node, orig_node->router,
 491                       hna_buff, tmp_hna_buff_len);
 492
 493 update_gw:
 494         if (orig_node->gw_flags != batman_packet->gw_flags)
 495                 gw_node_update(bat_priv, orig_node, batman_packet->gw_flags);
 496
 497         orig_node->gw_flags = batman_packet->gw_flags;
 498
 499         /* restart gateway selection if fast or late switching was enabled */
 500         if ((orig_node->gw_flags) &&
 501             (atomic_read(&bat_priv->gw_mode) == GW_MODE_CLIENT) &&
 502             (atomic_read(&bat_priv->gw_sel_class) > 2))
 503                 gw_check_election(bat_priv, orig_node);
 504
 505         goto out;
 506
 507 unlock:
 508         rcu_read_unlock();
 509 out:
 510         if (neigh_node)
 511                 neigh_node_free_ref(neigh_node);
 512 }
 513
 514 /* checks whether the host restarted and is in the protection time.
 515  * returns:
 516  *  0 if the packet is to be accepted
 517  *  1 if the packet is to be ignored.
 518  */
 519 static int window_protected(struct bat_priv *bat_priv,
 520                             int32_t seq_num_diff,
 521                             unsigned long *last_reset)
 522 {
 523         if ((seq_num_diff <= -TQ_LOCAL_WINDOW_SIZE)
 524                 || (seq_num_diff >= EXPECTED_SEQNO_RANGE)) {
 525                 if (time_after(jiffies, *last_reset +
 526                         msecs_to_jiffies(RESET_PROTECTION_MS))) {
 527
 528                         *last_reset = jiffies;
 529                         bat_dbg(DBG_BATMAN, bat_priv,
 530                                 "old packet received, start protection\n");
 531
 532                         return 0;
 533                 } else
 534                         return 1;
 535         }
 536         return 0;
 537 }
 538
 539 /* processes a batman packet for all interfaces, adjusts the sequence number and
 540  * finds out whether it is a duplicate.
 541  * returns:
 542  *   1 the packet is a duplicate
 543  *   0 the packet has not yet been received
 544  *  -1 the packet is old and has been received while the seqno window
 545  *     was protected. Caller should drop it.
 546  */
 547 static char count_real_packets(struct ethhdr *ethhdr,
 548                                struct batman_packet *batman_packet,
 549                                struct batman_if *if_incoming)
 550 {
 551         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 552         struct orig_node *orig_node;
 553         struct neigh_node *tmp_neigh_node;
 554         struct hlist_node *node;
 555         char is_duplicate = 0;
 556         int32_t seq_diff;
 557         int need_update = 0;
 558         int set_mark, ret = -1;
 559
 560         orig_node = get_orig_node(bat_priv, batman_packet->orig);
 561         if (!orig_node)
 562                 return 0;
 563
 564         spin_lock_bh(&orig_node->ogm_cnt_lock);
 565         seq_diff = batman_packet->seqno - orig_node->last_real_seqno;
 566
 567         /* signalize caller that the packet is to be dropped. */
 568         if (window_protected(bat_priv, seq_diff,
 569                              &orig_node->batman_seqno_reset))
 570                 goto out;
 571
 572         rcu_read_lock();
 573         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 574                                  &orig_node->neigh_list, list) {
 575
 576                 is_duplicate |= get_bit_status(tmp_neigh_node->real_bits,
 577                                                orig_node->last_real_seqno,
 578                                                batman_packet->seqno);
 579
 580                 if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) &&
 581                     (tmp_neigh_node->if_incoming == if_incoming))
 582                         set_mark = 1;
 583                 else
 584                         set_mark = 0;
 585
 586                 /* if the window moved, set the update flag. */
 587                 need_update |= bit_get_packet(bat_priv,
 588                                               tmp_neigh_node->real_bits,
 589                                               seq_diff, set_mark);
 590
 591                 tmp_neigh_node->real_packet_count =
 592                         bit_packet_count(tmp_neigh_node->real_bits);
 593         }
 594         rcu_read_unlock();
 595
 596         if (need_update) {
 597                 bat_dbg(DBG_BATMAN, bat_priv,
 598                         "updating last_seqno: old %d, new %d\n",
 599                         orig_node->last_real_seqno, batman_packet->seqno);
 600                 orig_node->last_real_seqno = batman_packet->seqno;
 601         }
 602
 603         ret = is_duplicate;
 604
 605 out:
 606         spin_unlock_bh(&orig_node->ogm_cnt_lock);
 607         orig_node_free_ref(orig_node);
 608         return ret;
 609 }
 610
 611 void receive_bat_packet(struct ethhdr *ethhdr,
 612                         struct batman_packet *batman_packet,
 613                         unsigned char *hna_buff, int hna_buff_len,
 614                         struct batman_if *if_incoming)
 615 {
 616         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 617         struct batman_if *batman_if;
 618         struct orig_node *orig_neigh_node, *orig_node;
 619         char has_directlink_flag;
 620         char is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
 621         char is_broadcast = 0, is_bidirectional, is_single_hop_neigh;
 622         char is_duplicate;
 623         uint32_t if_incoming_seqno;
 624
 625         /* Silently drop when the batman packet is actually not a
 626          * correct packet.
 627          *
 628          * This might happen if a packet is padded (e.g. Ethernet has a
 629          * minimum frame length of 64 byte) and the aggregation interprets
 630          * it as an additional length.
 631          *
 632          * TODO: A more sane solution would be to have a bit in the
 633          * batman_packet to detect whether the packet is the last
 634          * packet in an aggregation.  Here we expect that the padding
 635          * is always zero (or not 0x01)
 636          */
 637         if (batman_packet->packet_type != BAT_PACKET)
 638                 return;
 639
 640         /* could be changed by schedule_own_packet() */
 641         if_incoming_seqno = atomic_read(&if_incoming->seqno);
 642
 643         has_directlink_flag = (batman_packet->flags & DIRECTLINK ? 1 : 0);
 644
 645         is_single_hop_neigh = (compare_eth(ethhdr->h_source,
 646                                            batman_packet->orig) ? 1 : 0);
 647
 648         bat_dbg(DBG_BATMAN, bat_priv,
 649                 "Received BATMAN packet via NB: %pM, IF: %s [%pM] "
 650                 "(from OG: %pM, via prev OG: %pM, seqno %d, tq %d, "
 651                 "TTL %d, V %d, IDF %d)\n",
 652                 ethhdr->h_source, if_incoming->net_dev->name,
 653                 if_incoming->net_dev->dev_addr, batman_packet->orig,
 654                 batman_packet->prev_sender, batman_packet->seqno,
 655                 batman_packet->tq, batman_packet->ttl, batman_packet->version,
 656                 has_directlink_flag);
 657
 658         rcu_read_lock();
 659         list_for_each_entry_rcu(batman_if, &if_list, list) {
 660                 if (batman_if->if_status != IF_ACTIVE)
 661                         continue;
 662
 663                 if (batman_if->soft_iface != if_incoming->soft_iface)
 664                         continue;
 665
 666                 if (compare_eth(ethhdr->h_source,
 667                                 batman_if->net_dev->dev_addr))
 668                         is_my_addr = 1;
 669
 670                 if (compare_eth(batman_packet->orig,
 671                                 batman_if->net_dev->dev_addr))
 672                         is_my_orig = 1;
 673
 674                 if (compare_eth(batman_packet->prev_sender,
 675                                 batman_if->net_dev->dev_addr))
 676                         is_my_oldorig = 1;
 677
 678                 if (compare_eth(ethhdr->h_source, broadcast_addr))
 679                         is_broadcast = 1;
 680         }
 681         rcu_read_unlock();
 682
 683         if (batman_packet->version != COMPAT_VERSION) {
 684                 bat_dbg(DBG_BATMAN, bat_priv,
 685                         "Drop packet: incompatible batman version (%i)\n",
 686                         batman_packet->version);
 687                 return;
 688         }
 689
 690         if (is_my_addr) {
 691                 bat_dbg(DBG_BATMAN, bat_priv,
 692                         "Drop packet: received my own broadcast (sender: %pM"
 693                         ")\n",
 694                         ethhdr->h_source);
 695                 return;
 696         }
 697
 698         if (is_broadcast) {
 699                 bat_dbg(DBG_BATMAN, bat_priv, "Drop packet: "
 700                 "ignoring all packets with broadcast source addr (sender: %pM"
 701                 ")\n", ethhdr->h_source);
 702                 return;
 703         }
 704
 705         if (is_my_orig) {
 706                 unsigned long *word;
 707                 int offset;
 708
 709                 orig_neigh_node = get_orig_node(bat_priv, ethhdr->h_source);
 710                 if (!orig_neigh_node)
 711                         return;
 712
 713                 /* neighbor has to indicate direct link and it has to
 714                  * come via the corresponding interface */
 715                 /* if received seqno equals last send seqno save new
 716                  * seqno for bidirectional check */
 717                 if (has_directlink_flag &&
 718                     compare_eth(if_incoming->net_dev->dev_addr,
 719                                 batman_packet->orig) &&
 720                     (batman_packet->seqno - if_incoming_seqno + 2 == 0)) {
 721                         offset = if_incoming->if_num * NUM_WORDS;
 722
 723                         spin_lock_bh(&orig_neigh_node->ogm_cnt_lock);
 724                         word = &(orig_neigh_node->bcast_own[offset]);
 725                         bit_mark(word, 0);
 726                         orig_neigh_node->bcast_own_sum[if_incoming->if_num] =
 727                                 bit_packet_count(word);
 728                         spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);
 729                 }
 730
 731                 bat_dbg(DBG_BATMAN, bat_priv, "Drop packet: "
 732                         "originator packet from myself (via neighbor)\n");
 733                 orig_node_free_ref(orig_neigh_node);
 734                 return;
 735         }
 736
 737         if (is_my_oldorig) {
 738                 bat_dbg(DBG_BATMAN, bat_priv,
 739                         "Drop packet: ignoring all rebroadcast echos (sender: "
 740                         "%pM)\n", ethhdr->h_source);
 741                 return;
 742         }
 743
 744         orig_node = get_orig_node(bat_priv, batman_packet->orig);
 745         if (!orig_node)
 746                 return;
 747
 748         is_duplicate = count_real_packets(ethhdr, batman_packet, if_incoming);
 749
 750         if (is_duplicate == -1) {
 751                 bat_dbg(DBG_BATMAN, bat_priv,
 752                         "Drop packet: packet within seqno protection time "
 753                         "(sender: %pM)\n", ethhdr->h_source);
 754                 goto out;
 755         }
 756
 757         if (batman_packet->tq == 0) {
 758                 bat_dbg(DBG_BATMAN, bat_priv,
 759                         "Drop packet: originator packet with tq equal 0\n");
 760                 goto out;
 761         }
 762
 763         /* avoid temporary routing loops */
 764         if ((orig_node->router) &&
 765             (orig_node->router->orig_node->router) &&
 766             (compare_eth(orig_node->router->addr,
 767                          batman_packet->prev_sender)) &&
 768             !(compare_eth(batman_packet->orig, batman_packet->prev_sender)) &&
 769             (compare_eth(orig_node->router->addr,
 770                          orig_node->router->orig_node->router->addr))) {
 771                 bat_dbg(DBG_BATMAN, bat_priv,
 772                         "Drop packet: ignoring all rebroadcast packets that "
 773                         "may make me loop (sender: %pM)\n", ethhdr->h_source);
 774                 goto out;
 775         }
 776
 777         /* if sender is a direct neighbor the sender mac equals
 778          * originator mac */
 779         orig_neigh_node = (is_single_hop_neigh ?
 780                            orig_node :
 781                            get_orig_node(bat_priv, ethhdr->h_source));
 782         if (!orig_neigh_node)
 783                 goto out_neigh;
 784
 785         /* drop packet if sender is not a direct neighbor and if we
 786          * don't route towards it */
 787         if (!is_single_hop_neigh && (!orig_neigh_node->router)) {
 788                 bat_dbg(DBG_BATMAN, bat_priv,
 789                         "Drop packet: OGM via unknown neighbor!\n");
 790                 goto out_neigh;
 791         }
 792
 793         is_bidirectional = is_bidirectional_neigh(orig_node, orig_neigh_node,
 794                                                 batman_packet, if_incoming);
 795
 796         bonding_save_primary(orig_node, orig_neigh_node, batman_packet);
 797
 798         /* update ranking if it is not a duplicate or has the same
 799          * seqno and similar ttl as the non-duplicate */
 800         if (is_bidirectional &&
 801             (!is_duplicate ||
 802              ((orig_node->last_real_seqno == batman_packet->seqno) &&
 803               (orig_node->last_ttl - 3 <= batman_packet->ttl))))
 804                 update_orig(bat_priv, orig_node, ethhdr, batman_packet,
 805                             if_incoming, hna_buff, hna_buff_len, is_duplicate);
 806
 807         /* is single hop (direct) neighbor */
 808         if (is_single_hop_neigh) {
 809
 810                 /* mark direct link on incoming interface */
 811                 schedule_forward_packet(orig_node, ethhdr, batman_packet,
 812                                         1, hna_buff_len, if_incoming);
 813
 814                 bat_dbg(DBG_BATMAN, bat_priv, "Forwarding packet: "
 815                         "rebroadcast neighbor packet with direct link flag\n");
 816                 goto out_neigh;
 817         }
 818
 819         /* multihop originator */
 820         if (!is_bidirectional) {
 821                 bat_dbg(DBG_BATMAN, bat_priv,
 822                         "Drop packet: not received via bidirectional link\n");
 823                 goto out_neigh;
 824         }
 825
 826         if (is_duplicate) {
 827                 bat_dbg(DBG_BATMAN, bat_priv,
 828                         "Drop packet: duplicate packet received\n");
 829                 goto out_neigh;
 830         }
 831
 832         bat_dbg(DBG_BATMAN, bat_priv,
 833                 "Forwarding packet: rebroadcast originator packet\n");
 834         schedule_forward_packet(orig_node, ethhdr, batman_packet,
 835                                 0, hna_buff_len, if_incoming);
 836
 837 out_neigh:
 838         if ((orig_neigh_node) && (!is_single_hop_neigh))
 839                 orig_node_free_ref(orig_neigh_node);
 840 out:
 841         orig_node_free_ref(orig_node);
 842 }
 843
 844 int recv_bat_packet(struct sk_buff *skb, struct batman_if *batman_if)
 845 {
 846         struct bat_priv *bat_priv = netdev_priv(batman_if->soft_iface);
 847         struct ethhdr *ethhdr;
 848
 849         /* drop packet if it has not necessary minimum size */
 850         if (unlikely(!pskb_may_pull(skb, sizeof(struct batman_packet))))
 851                 return NET_RX_DROP;
 852
 853         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 854
 855         /* packet with broadcast indication but unicast recipient */
 856         if (!is_broadcast_ether_addr(ethhdr->h_dest))
 857                 return NET_RX_DROP;
 858
 859         /* packet with broadcast sender address */
 860         if (is_broadcast_ether_addr(ethhdr->h_source))
 861                 return NET_RX_DROP;
 862
 863         /* create a copy of the skb, if needed, to modify it. */
 864         if (skb_cow(skb, 0) < 0)
 865                 return NET_RX_DROP;
 866
 867         /* keep skb linear */
 868         if (skb_linearize(skb) < 0)
 869                 return NET_RX_DROP;
 870
 871         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 872
 873         spin_lock_bh(&bat_priv->orig_hash_lock);
 874         receive_aggr_bat_packet(ethhdr,
 875                                 skb->data,
 876                                 skb_headlen(skb),
 877                                 batman_if);
 878         spin_unlock_bh(&bat_priv->orig_hash_lock);
 879
 880         kfree_skb(skb);
 881         return NET_RX_SUCCESS;
 882 }
 883
 884 static int recv_my_icmp_packet(struct bat_priv *bat_priv,
 885                                struct sk_buff *skb, size_t icmp_len)
 886 {
 887         struct orig_node *orig_node = NULL;
 888         struct neigh_node *neigh_node = NULL;
 889         struct icmp_packet_rr *icmp_packet;
 890         struct batman_if *batman_if;
 891         uint8_t dstaddr[ETH_ALEN];
 892         int ret = NET_RX_DROP;
 893
 894         icmp_packet = (struct icmp_packet_rr *)skb->data;
 895
 896         /* add data to device queue */
 897         if (icmp_packet->msg_type != ECHO_REQUEST) {
 898                 bat_socket_receive_packet(icmp_packet, icmp_len);
 899                 goto out;
 900         }
 901
 902         if (!bat_priv->primary_if)
 903                 goto out;
 904
 905         /* answer echo request (ping) */
 906         /* get routing information */
 907         spin_lock_bh(&bat_priv->orig_hash_lock);
 908         rcu_read_lock();
 909         orig_node = orig_hash_find(bat_priv, icmp_packet->orig);
 910
 911         if (!orig_node)
 912                 goto unlock;
 913
 914         neigh_node = orig_node->router;
 915
 916         if (!neigh_node)
 917                 goto unlock;
 918
 919         if (!atomic_inc_not_zero(&neigh_node->refcount)) {
 920                 neigh_node = NULL;
 921                 goto unlock;
 922         }
 923
 924         rcu_read_unlock();
 925
 926         /* don't lock while sending the packets ... we therefore
 927          * copy the required data before sending */
 928         batman_if = orig_node->router->if_incoming;
 929         memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 930         spin_unlock_bh(&bat_priv->orig_hash_lock);
 931
 932         /* create a copy of the skb, if needed, to modify it. */
 933         if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
 934                 goto out;
 935
 936         icmp_packet = (struct icmp_packet_rr *)skb->data;
 937
 938         memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
 939         memcpy(icmp_packet->orig,
 940                 bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN);
 941         icmp_packet->msg_type = ECHO_REPLY;
 942         icmp_packet->ttl = TTL;
 943
 944         send_skb_packet(skb, batman_if, dstaddr);
 945         ret = NET_RX_SUCCESS;
 946         goto out;
 947
 948 unlock:
 949         rcu_read_unlock();
 950         spin_unlock_bh(&bat_priv->orig_hash_lock);
 951 out:
 952         if (neigh_node)
 953                 neigh_node_free_ref(neigh_node);
 954         if (orig_node)
 955                 orig_node_free_ref(orig_node);
 956         return ret;
 957 }
 958
 959 static int recv_icmp_ttl_exceeded(struct bat_priv *bat_priv,
 960                                   struct sk_buff *skb)
 961 {
 962         struct orig_node *orig_node = NULL;
 963         struct neigh_node *neigh_node = NULL;
 964         struct icmp_packet *icmp_packet;
 965         struct batman_if *batman_if;
 966         uint8_t dstaddr[ETH_ALEN];
 967         int ret = NET_RX_DROP;
 968
 969         icmp_packet = (struct icmp_packet *)skb->data;
 970
 971         /* send TTL exceeded if packet is an echo request (traceroute) */
 972         if (icmp_packet->msg_type != ECHO_REQUEST) {
 973                 pr_debug("Warning - can't forward icmp packet from %pM to "
 974                          "%pM: ttl exceeded\n", icmp_packet->orig,
 975                          icmp_packet->dst);
 976                 goto out;
 977         }
 978
 979         if (!bat_priv->primary_if)
 980                 goto out;
 981
 982         /* get routing information */
 983         spin_lock_bh(&bat_priv->orig_hash_lock);
 984         rcu_read_lock();
 985         orig_node = orig_hash_find(bat_priv, icmp_packet->orig);
 986
 987         if (!orig_node)
 988                 goto unlock;
 989
 990         neigh_node = orig_node->router;
 991
 992         if (!neigh_node)
 993                 goto unlock;
 994
 995         if (!atomic_inc_not_zero(&neigh_node->refcount)) {
 996                 neigh_node = NULL;
 997                 goto unlock;
 998         }
 999
1000         rcu_read_unlock();
1001
1002         /* don't lock while sending the packets ... we therefore
1003          * copy the required data before sending */
1004         batman_if = orig_node->router->if_incoming;
1005         memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
1006         spin_unlock_bh(&bat_priv->orig_hash_lock);
1007
1008         /* create a copy of the skb, if needed, to modify it. */
1009         if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
1010                 goto out;
1011
1012         icmp_packet = (struct icmp_packet *)skb->data;
1013
1014         memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
1015         memcpy(icmp_packet->orig,
1016                 bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN);
1017         icmp_packet->msg_type = TTL_EXCEEDED;
1018         icmp_packet->ttl = TTL;
1019
1020         send_skb_packet(skb, batman_if, dstaddr);
1021         ret = NET_RX_SUCCESS;
1022         goto out;
1023
1024 unlock:
1025         rcu_read_unlock();
1026         spin_unlock_bh(&bat_priv->orig_hash_lock);
1027 out:
1028         if (neigh_node)
1029                 neigh_node_free_ref(neigh_node);
1030         if (orig_node)
1031                 orig_node_free_ref(orig_node);
1032         return ret;
1033 }
1034
1035
1036 int recv_icmp_packet(struct sk_buff *skb, struct batman_if *recv_if)
1037 {
1038         struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1039         struct icmp_packet_rr *icmp_packet;
1040         struct ethhdr *ethhdr;
1041         struct orig_node *orig_node = NULL;
1042         struct neigh_node *neigh_node = NULL;
1043         struct batman_if *batman_if;
1044         int hdr_size = sizeof(struct icmp_packet);
1045         uint8_t dstaddr[ETH_ALEN];
1046         int ret = NET_RX_DROP;
1047
1048         /**
1049          * we truncate all incoming icmp packets if they don't match our size
1050          */
1051         if (skb->len >= sizeof(struct icmp_packet_rr))
1052                 hdr_size = sizeof(struct icmp_packet_rr);
1053
1054         /* drop packet if it has not necessary minimum size */
1055         if (unlikely(!pskb_may_pull(skb, hdr_size)))
1056                 goto out;
1057
1058         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1059
1060         /* packet with unicast indication but broadcast recipient */
1061         if (is_broadcast_ether_addr(ethhdr->h_dest))
1062                 goto out;
1063
1064         /* packet with broadcast sender address */
1065         if (is_broadcast_ether_addr(ethhdr->h_source))
1066                 goto out;
1067
1068         /* not for me */
1069         if (!is_my_mac(ethhdr->h_dest))
1070                 goto out;
1071
1072         icmp_packet = (struct icmp_packet_rr *)skb->data;
1073
1074         /* add record route information if not full */
1075         if ((hdr_size == sizeof(struct icmp_packet_rr)) &&
1076             (icmp_packet->rr_cur < BAT_RR_LEN)) {
1077                 memcpy(&(icmp_packet->rr[icmp_packet->rr_cur]),
1078                         ethhdr->h_dest, ETH_ALEN);
1079                 icmp_packet->rr_cur++;
1080         }
1081
1082         /* packet for me */
1083         if (is_my_mac(icmp_packet->dst))
1084                 return recv_my_icmp_packet(bat_priv, skb, hdr_size);
1085
1086         /* TTL exceeded */
1087         if (icmp_packet->ttl < 2)
1088                 return recv_icmp_ttl_exceeded(bat_priv, skb);
1089
1090         /* get routing information */
1091         spin_lock_bh(&bat_priv->orig_hash_lock);
1092         rcu_read_lock();
1093         orig_node = orig_hash_find(bat_priv, icmp_packet->dst);
1094
1095         if (!orig_node)
1096                 goto unlock;
1097
1098         neigh_node = orig_node->router;
1099
1100         if (!neigh_node)
1101                 goto unlock;
1102
1103         if (!atomic_inc_not_zero(&neigh_node->refcount)) {
1104                 neigh_node = NULL;
1105                 goto unlock;
1106         }
1107
1108         rcu_read_unlock();
1109
1110         /* don't lock while sending the packets ... we therefore
1111          * copy the required data before sending */
1112         batman_if = orig_node->router->if_incoming;
1113         memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
1114         spin_unlock_bh(&bat_priv->orig_hash_lock);
1115
1116         /* create a copy of the skb, if needed, to modify it. */
1117         if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
1118                 goto out;
1119
1120         icmp_packet = (struct icmp_packet_rr *)skb->data;
1121
1122         /* decrement ttl */
1123         icmp_packet->ttl--;
1124
1125         /* route it */
1126         send_skb_packet(skb, batman_if, dstaddr);
1127         ret = NET_RX_SUCCESS;
1128         goto out;
1129
1130 unlock:
1131         rcu_read_unlock();
1132         spin_unlock_bh(&bat_priv->orig_hash_lock);
1133 out:
1134         if (neigh_node)
1135                 neigh_node_free_ref(neigh_node);
1136         if (orig_node)
1137                 orig_node_free_ref(orig_node);
1138         return ret;
1139 }
1140
1141 /* find a suitable router for this originator, and use
1142  * bonding if possible. increases the found neighbors
1143  * refcount.*/
1144 struct neigh_node *find_router(struct bat_priv *bat_priv,
1145                                struct orig_node *orig_node,
1146                                struct batman_if *recv_if)
1147 {
1148         struct orig_node *primary_orig_node;
1149         struct orig_node *router_orig;
1150         struct neigh_node *router, *first_candidate, *tmp_neigh_node;
1151         static uint8_t zero_mac[ETH_ALEN] = {0, 0, 0, 0, 0, 0};
1152         int bonding_enabled;
1153
1154         if (!orig_node)
1155                 return NULL;
1156
1157         if (!orig_node->router)
1158                 return NULL;
1159
1160         /* without bonding, the first node should
1161          * always choose the default router. */
1162         bonding_enabled = atomic_read(&bat_priv->bonding);
1163
1164         rcu_read_lock();
1165         /* select default router to output */
1166         router = orig_node->router;
1167         router_orig = orig_node->router->orig_node;
1168         if (!router_orig || !atomic_inc_not_zero(&router->refcount)) {
1169                 rcu_read_unlock();
1170                 return NULL;
1171         }
1172
1173         if ((!recv_if) && (!bonding_enabled))
1174                 goto return_router;
1175
1176         /* if we have something in the primary_addr, we can search
1177          * for a potential bonding candidate. */
1178         if (compare_eth(router_orig->primary_addr, zero_mac))
1179                 goto return_router;
1180
1181         /* find the orig_node which has the primary interface. might
1182          * even be the same as our router_orig in many cases */
1183
1184         if (compare_eth(router_orig->primary_addr, router_orig->orig)) {
1185                 primary_orig_node = router_orig;
1186         } else {
1187                 primary_orig_node = orig_hash_find(bat_priv,
1188                                                    router_orig->primary_addr);
1189                 if (!primary_orig_node)
1190                         goto return_router;
1191
1192                 orig_node_free_ref(primary_orig_node);
1193         }
1194
1195         /* with less than 2 candidates, we can't do any
1196          * bonding and prefer the original router. */
1197         if (atomic_read(&primary_orig_node->bond_candidates) < 2)
1198                 goto return_router;
1199
1200
1201         /* all nodes between should choose a candidate which
1202          * is is not on the interface where the packet came
1203          * in. */
1204
1205         neigh_node_free_ref(router);
1206         first_candidate = NULL;
1207         router = NULL;
1208
1209         if (bonding_enabled) {
1210                 /* in the bonding case, send the packets in a round
1211                  * robin fashion over the remaining interfaces. */
1212
1213                 list_for_each_entry_rcu(tmp_neigh_node,
1214                                 &primary_orig_node->bond_list, bonding_list) {
1215                         if (!first_candidate)
1216                                 first_candidate = tmp_neigh_node;
1217                         /* recv_if == NULL on the first node. */
1218                         if (tmp_neigh_node->if_incoming != recv_if &&
1219                             atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
1220                                 router = tmp_neigh_node;
1221                                 break;
1222                         }
1223                 }
1224
1225                 /* use the first candidate if nothing was found. */
1226                 if (!router && first_candidate &&
1227                     atomic_inc_not_zero(&first_candidate->refcount))
1228                         router = first_candidate;
1229
1230                 if (!router) {
1231                         rcu_read_unlock();
1232                         return NULL;
1233                 }
1234
1235                 /* selected should point to the next element
1236                  * after the current router */
1237                 spin_lock_bh(&primary_orig_node->neigh_list_lock);
1238                 /* this is a list_move(), which unfortunately
1239                  * does not exist as rcu version */
1240                 list_del_rcu(&primary_orig_node->bond_list);
1241                 list_add_rcu(&primary_orig_node->bond_list,
1242                                 &router->bonding_list);
1243                 spin_unlock_bh(&primary_orig_node->neigh_list_lock);
1244
1245         } else {
1246                 /* if bonding is disabled, use the best of the
1247                  * remaining candidates which are not using
1248                  * this interface. */
1249                 list_for_each_entry_rcu(tmp_neigh_node,
1250                         &primary_orig_node->bond_list, bonding_list) {
1251                         if (!first_candidate)
1252                                 first_candidate = tmp_neigh_node;
1253
1254                         /* recv_if == NULL on the first node. */
1255                         if (tmp_neigh_node->if_incoming == recv_if)
1256                                 continue;
1257
1258                         if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
1259                                 continue;
1260
1261                         /* if we don't have a router yet
1262                          * or this one is better, choose it. */
1263                         if ((!router) ||
1264                             (tmp_neigh_node->tq_avg > router->tq_avg)) {
1265                                 /* decrement refcount of
1266                                  * previously selected router */
1267                                 if (router)
1268                                         neigh_node_free_ref(router);
1269
1270                                 router = tmp_neigh_node;
1271                                 atomic_inc_not_zero(&router->refcount);
1272                         }
1273
1274                         neigh_node_free_ref(tmp_neigh_node);
1275                 }
1276
1277                 /* use the first candidate if nothing was found. */
1278                 if (!router && first_candidate &&
1279                     atomic_inc_not_zero(&first_candidate->refcount))
1280                         router = first_candidate;
1281         }
1282 return_router:
1283         rcu_read_unlock();
1284         return router;
1285 }
1286
1287 static int check_unicast_packet(struct sk_buff *skb, int hdr_size)
1288 {
1289         struct ethhdr *ethhdr;
1290
1291         /* drop packet if it has not necessary minimum size */
1292         if (unlikely(!pskb_may_pull(skb, hdr_size)))
1293                 return -1;
1294
1295         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1296
1297         /* packet with unicast indication but broadcast recipient */
1298         if (is_broadcast_ether_addr(ethhdr->h_dest))
1299                 return -1;
1300
1301         /* packet with broadcast sender address */
1302         if (is_broadcast_ether_addr(ethhdr->h_source))
1303                 return -1;
1304
1305         /* not for me */
1306         if (!is_my_mac(ethhdr->h_dest))
1307                 return -1;
1308
1309         return 0;
1310 }
1311
1312 int route_unicast_packet(struct sk_buff *skb, struct batman_if *recv_if,
1313                          int hdr_size)
1314 {
1315         struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1316         struct orig_node *orig_node = NULL;
1317         struct neigh_node *neigh_node = NULL;
1318         struct batman_if *batman_if;
1319         uint8_t dstaddr[ETH_ALEN];
1320         struct unicast_packet *unicast_packet;
1321         struct ethhdr *ethhdr = (struct ethhdr *)skb_mac_header(skb);
1322         int ret = NET_RX_DROP;
1323         struct sk_buff *new_skb;
1324
1325         unicast_packet = (struct unicast_packet *)skb->data;
1326
1327         /* TTL exceeded */
1328         if (unicast_packet->ttl < 2) {
1329                 pr_debug("Warning - can't forward unicast packet from %pM to "
1330                          "%pM: ttl exceeded\n", ethhdr->h_source,
1331                          unicast_packet->dest);
1332                 goto out;
1333         }
1334
1335         /* get routing information */
1336         spin_lock_bh(&bat_priv->orig_hash_lock);
1337         rcu_read_lock();
1338         orig_node = orig_hash_find(bat_priv, unicast_packet->dest);
1339
1340         if (!orig_node)
1341                 goto unlock;
1342
1343         rcu_read_unlock();
1344
1345         /* find_router() increases neigh_nodes refcount if found. */
1346         neigh_node = find_router(bat_priv, orig_node, recv_if);
1347
1348         if (!neigh_node) {
1349                 spin_unlock_bh(&bat_priv->orig_hash_lock);
1350                 goto out;
1351         }
1352
1353         /* don't lock while sending the packets ... we therefore
1354          * copy the required data before sending */
1355         batman_if = neigh_node->if_incoming;
1356         memcpy(dstaddr, neigh_node->addr, ETH_ALEN);
1357         spin_unlock_bh(&bat_priv->orig_hash_lock);
1358
1359         /* create a copy of the skb, if needed, to modify it. */
1360         if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
1361                 goto out;
1362
1363         unicast_packet = (struct unicast_packet *)skb->data;
1364
1365         if (unicast_packet->packet_type == BAT_UNICAST &&
1366             atomic_read(&bat_priv->fragmentation) &&
1367             skb->len > batman_if->net_dev->mtu)
1368                 return frag_send_skb(skb, bat_priv, batman_if,
1369                                      dstaddr);
1370
1371         if (unicast_packet->packet_type == BAT_UNICAST_FRAG &&
1372             frag_can_reassemble(skb, batman_if->net_dev->mtu)) {
1373
1374                 ret = frag_reassemble_skb(skb, bat_priv, &new_skb);
1375
1376                 if (ret == NET_RX_DROP)
1377                         goto out;
1378
1379                 /* packet was buffered for late merge */
1380                 if (!new_skb) {
1381                         ret = NET_RX_SUCCESS;
1382                         goto out;
1383                 }
1384
1385                 skb = new_skb;
1386                 unicast_packet = (struct unicast_packet *)skb->data;
1387         }
1388
1389         /* decrement ttl */
1390         unicast_packet->ttl--;
1391
1392         /* route it */
1393         send_skb_packet(skb, batman_if, dstaddr);
1394         ret = NET_RX_SUCCESS;
1395         goto out;
1396
1397 unlock:
1398         rcu_read_unlock();
1399         spin_unlock_bh(&bat_priv->orig_hash_lock);
1400 out:
1401         if (neigh_node)
1402                 neigh_node_free_ref(neigh_node);
1403         if (orig_node)
1404                 orig_node_free_ref(orig_node);
1405         return ret;
1406 }
1407
1408 int recv_unicast_packet(struct sk_buff *skb, struct batman_if *recv_if)
1409 {
1410         struct unicast_packet *unicast_packet;
1411         int hdr_size = sizeof(struct unicast_packet);
1412
1413         if (check_unicast_packet(skb, hdr_size) < 0)
1414                 return NET_RX_DROP;
1415
1416         unicast_packet = (struct unicast_packet *)skb->data;
1417
1418         /* packet for me */
1419         if (is_my_mac(unicast_packet->dest)) {
1420                 interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size);
1421                 return NET_RX_SUCCESS;
1422         }
1423
1424         return route_unicast_packet(skb, recv_if, hdr_size);
1425 }
1426
1427 int recv_ucast_frag_packet(struct sk_buff *skb, struct batman_if *recv_if)
1428 {
1429         struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1430         struct unicast_frag_packet *unicast_packet;
1431         int hdr_size = sizeof(struct unicast_frag_packet);
1432         struct sk_buff *new_skb = NULL;
1433         int ret;
1434
1435         if (check_unicast_packet(skb, hdr_size) < 0)
1436                 return NET_RX_DROP;
1437
1438         unicast_packet = (struct unicast_frag_packet *)skb->data;
1439
1440         /* packet for me */
1441         if (is_my_mac(unicast_packet->dest)) {
1442
1443                 ret = frag_reassemble_skb(skb, bat_priv, &new_skb);
1444
1445                 if (ret == NET_RX_DROP)
1446                         return NET_RX_DROP;
1447
1448                 /* packet was buffered for late merge */
1449                 if (!new_skb)
1450                         return NET_RX_SUCCESS;
1451
1452                 interface_rx(recv_if->soft_iface, new_skb, recv_if,
1453                              sizeof(struct unicast_packet));
1454                 return NET_RX_SUCCESS;
1455         }
1456
1457         return route_unicast_packet(skb, recv_if, hdr_size);
1458 }
1459
1460
1461 int recv_bcast_packet(struct sk_buff *skb, struct batman_if *recv_if)
1462 {
1463         struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1464         struct orig_node *orig_node = NULL;
1465         struct bcast_packet *bcast_packet;
1466         struct ethhdr *ethhdr;
1467         int hdr_size = sizeof(struct bcast_packet);
1468         int ret = NET_RX_DROP;
1469         int32_t seq_diff;
1470
1471         /* drop packet if it has not necessary minimum size */
1472         if (unlikely(!pskb_may_pull(skb, hdr_size)))
1473                 goto out;
1474
1475         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1476
1477         /* packet with broadcast indication but unicast recipient */
1478         if (!is_broadcast_ether_addr(ethhdr->h_dest))
1479                 goto out;
1480
1481         /* packet with broadcast sender address */
1482         if (is_broadcast_ether_addr(ethhdr->h_source))
1483                 goto out;
1484
1485         /* ignore broadcasts sent by myself */
1486         if (is_my_mac(ethhdr->h_source))
1487                 goto out;
1488
1489         bcast_packet = (struct bcast_packet *)skb->data;
1490
1491         /* ignore broadcasts originated by myself */
1492         if (is_my_mac(bcast_packet->orig))
1493                 goto out;
1494
1495         if (bcast_packet->ttl < 2)
1496                 goto out;
1497
1498         spin_lock_bh(&bat_priv->orig_hash_lock);
1499         rcu_read_lock();
1500         orig_node = orig_hash_find(bat_priv, bcast_packet->orig);
1501
1502         if (!orig_node)
1503                 goto rcu_unlock;
1504
1505         rcu_read_unlock();
1506
1507         spin_lock_bh(&orig_node->bcast_seqno_lock);
1508
1509         /* check whether the packet is a duplicate */
1510         if (get_bit_status(orig_node->bcast_bits, orig_node->last_bcast_seqno,
1511                            ntohl(bcast_packet->seqno)))
1512                 goto spin_unlock;
1513
1514         seq_diff = ntohl(bcast_packet->seqno) - orig_node->last_bcast_seqno;
1515
1516         /* check whether the packet is old and the host just restarted. */
1517         if (window_protected(bat_priv, seq_diff,
1518                              &orig_node->bcast_seqno_reset))
1519                 goto spin_unlock;
1520
1521         /* mark broadcast in flood history, update window position
1522          * if required. */
1523         if (bit_get_packet(bat_priv, orig_node->bcast_bits, seq_diff, 1))
1524                 orig_node->last_bcast_seqno = ntohl(bcast_packet->seqno);
1525
1526         spin_unlock_bh(&orig_node->bcast_seqno_lock);
1527         spin_unlock_bh(&bat_priv->orig_hash_lock);
1528
1529         /* rebroadcast packet */
1530         add_bcast_packet_to_list(bat_priv, skb);
1531
1532         /* broadcast for me */
1533         interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size);
1534         ret = NET_RX_SUCCESS;
1535         goto out;
1536
1537 rcu_unlock:
1538         rcu_read_unlock();
1539         spin_unlock_bh(&bat_priv->orig_hash_lock);
1540         goto out;
1541 spin_unlock:
1542         spin_unlock_bh(&orig_node->bcast_seqno_lock);
1543         spin_unlock_bh(&bat_priv->orig_hash_lock);
1544 out:
1545         if (orig_node)
1546                 orig_node_free_ref(orig_node);
1547         return ret;
1548 }
1549
1550 int recv_vis_packet(struct sk_buff *skb, struct batman_if *recv_if)
1551 {
1552         struct vis_packet *vis_packet;
1553         struct ethhdr *ethhdr;
1554         struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1555         int hdr_size = sizeof(struct vis_packet);
1556
1557         /* keep skb linear */
1558         if (skb_linearize(skb) < 0)
1559                 return NET_RX_DROP;
1560
1561         if (unlikely(!pskb_may_pull(skb, hdr_size)))
1562                 return NET_RX_DROP;
1563
1564         vis_packet = (struct vis_packet *)skb->data;
1565         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1566
1567         /* not for me */
1568         if (!is_my_mac(ethhdr->h_dest))
1569                 return NET_RX_DROP;
1570
1571         /* ignore own packets */
1572         if (is_my_mac(vis_packet->vis_orig))
1573                 return NET_RX_DROP;
1574
1575         if (is_my_mac(vis_packet->sender_orig))
1576                 return NET_RX_DROP;
1577
1578         switch (vis_packet->vis_type) {
1579         case VIS_TYPE_SERVER_SYNC:
1580                 receive_server_sync_packet(bat_priv, vis_packet,
1581                                            skb_headlen(skb));
1582                 break;
1583
1584         case VIS_TYPE_CLIENT_UPDATE:
1585                 receive_client_update_packet(bat_priv, vis_packet,
1586                                              skb_headlen(skb));
1587                 break;
1588
1589         default:        /* ignore unknown packet */
1590                 break;
1591         }
1592
1593         /* We take a copy of the data in the packet, so we should
1594            always free the skbuf. */
1595         return NET_RX_DROP;
1596 }