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 *walk;
  43         struct hlist_head *head;
  44         struct element_t *bucket;
  45         struct orig_node *orig_node;
  46         unsigned long *word;
  47         int i;
  48         size_t word_index;
  49
  50         spin_lock_bh(&bat_priv->orig_hash_lock);
  51
  52         for (i = 0; i < hash->size; i++) {
  53                 head = &hash->table[i];
  54
  55                 rcu_read_lock();
  56                 hlist_for_each_entry_rcu(bucket, walk, head, hlist) {
  57                         orig_node = bucket->data;
  58                         word_index = batman_if->if_num * NUM_WORDS;
  59                         word = &(orig_node->bcast_own[word_index]);
  60
  61                         bit_get_packet(bat_priv, word, 1, 0);
  62                         orig_node->bcast_own_sum[batman_if->if_num] =
  63                                 bit_packet_count(word);
  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)
 123                 kref_get(&neigh_node->refcount);
 124         neigh_node_tmp = orig_node->router;
 125         orig_node->router = neigh_node;
 126         if (neigh_node_tmp)
 127                 kref_put(&neigh_node_tmp->refcount, neigh_node_free_ref);
 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         int ret = 0;
 157
 158         if (orig_node == orig_neigh_node) {
 159                 rcu_read_lock();
 160                 hlist_for_each_entry_rcu(tmp_neigh_node, node,
 161                                          &orig_node->neigh_list, list) {
 162
 163                         if (compare_orig(tmp_neigh_node->addr,
 164                                          orig_neigh_node->orig) &&
 165                             (tmp_neigh_node->if_incoming == if_incoming))
 166                                 neigh_node = tmp_neigh_node;
 167                 }
 168
 169                 if (!neigh_node)
 170                         neigh_node = create_neighbor(orig_node,
 171                                                      orig_neigh_node,
 172                                                      orig_neigh_node->orig,
 173                                                      if_incoming);
 174                 /* create_neighbor failed, return 0 */
 175                 if (!neigh_node)
 176                         goto unlock;
 177
 178                 kref_get(&neigh_node->refcount);
 179                 rcu_read_unlock();
 180
 181                 neigh_node->last_valid = jiffies;
 182         } else {
 183                 /* find packet count of corresponding one hop neighbor */
 184                 rcu_read_lock();
 185                 hlist_for_each_entry_rcu(tmp_neigh_node, node,
 186                                          &orig_neigh_node->neigh_list, list) {
 187
 188                         if (compare_orig(tmp_neigh_node->addr,
 189                                          orig_neigh_node->orig) &&
 190                             (tmp_neigh_node->if_incoming == if_incoming))
 191                                 neigh_node = tmp_neigh_node;
 192                 }
 193
 194                 if (!neigh_node)
 195                         neigh_node = create_neighbor(orig_neigh_node,
 196                                                      orig_neigh_node,
 197                                                      orig_neigh_node->orig,
 198                                                      if_incoming);
 199                 /* create_neighbor failed, return 0 */
 200                 if (!neigh_node)
 201                         goto unlock;
 202
 203                 kref_get(&neigh_node->refcount);
 204                 rcu_read_unlock();
 205         }
 206
 207         orig_node->last_valid = jiffies;
 208
 209         /* pay attention to not get a value bigger than 100 % */
 210         total_count = (orig_neigh_node->bcast_own_sum[if_incoming->if_num] >
 211                        neigh_node->real_packet_count ?
 212                        neigh_node->real_packet_count :
 213                        orig_neigh_node->bcast_own_sum[if_incoming->if_num]);
 214
 215         /* if we have too few packets (too less data) we set tq_own to zero */
 216         /* if we receive too few packets it is not considered bidirectional */
 217         if ((total_count < TQ_LOCAL_BIDRECT_SEND_MINIMUM) ||
 218             (neigh_node->real_packet_count < TQ_LOCAL_BIDRECT_RECV_MINIMUM))
 219                 orig_neigh_node->tq_own = 0;
 220         else
 221                 /* neigh_node->real_packet_count is never zero as we
 222                  * only purge old information when getting new
 223                  * information */
 224                 orig_neigh_node->tq_own = (TQ_MAX_VALUE * total_count) /
 225                         neigh_node->real_packet_count;
 226
 227         /*
 228          * 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
 229          * affect the nearly-symmetric links only a little, but
 230          * punishes asymmetric links more.  This will give a value
 231          * between 0 and TQ_MAX_VALUE
 232          */
 233         orig_neigh_node->tq_asym_penalty =
 234                 TQ_MAX_VALUE -
 235                 (TQ_MAX_VALUE *
 236                  (TQ_LOCAL_WINDOW_SIZE - neigh_node->real_packet_count) *
 237                  (TQ_LOCAL_WINDOW_SIZE - neigh_node->real_packet_count) *
 238                  (TQ_LOCAL_WINDOW_SIZE - neigh_node->real_packet_count)) /
 239                 (TQ_LOCAL_WINDOW_SIZE *
 240                  TQ_LOCAL_WINDOW_SIZE *
 241                  TQ_LOCAL_WINDOW_SIZE);
 242
 243         batman_packet->tq = ((batman_packet->tq *
 244                               orig_neigh_node->tq_own *
 245                               orig_neigh_node->tq_asym_penalty) /
 246                              (TQ_MAX_VALUE * TQ_MAX_VALUE));
 247
 248         bat_dbg(DBG_BATMAN, bat_priv,
 249                 "bidirectional: "
 250                 "orig = %-15pM neigh = %-15pM => own_bcast = %2i, "
 251                 "real recv = %2i, local tq: %3i, asym_penalty: %3i, "
 252                 "total tq: %3i\n",
 253                 orig_node->orig, orig_neigh_node->orig, total_count,
 254                 neigh_node->real_packet_count, orig_neigh_node->tq_own,
 255                 orig_neigh_node->tq_asym_penalty, batman_packet->tq);
 256
 257         /* if link has the minimum required transmission quality
 258          * consider it bidirectional */
 259         if (batman_packet->tq >= TQ_TOTAL_BIDRECT_LIMIT)
 260                 ret = 1;
 261
 262         goto out;
 263
 264 unlock:
 265         rcu_read_unlock();
 266 out:
 267         if (neigh_node)
 268                 kref_put(&neigh_node->refcount, neigh_node_free_ref);
 269         return ret;
 270 }
 271
 272 static void update_orig(struct bat_priv *bat_priv,
 273                         struct orig_node *orig_node,
 274                         struct ethhdr *ethhdr,
 275                         struct batman_packet *batman_packet,
 276                         struct batman_if *if_incoming,
 277                         unsigned char *hna_buff, int hna_buff_len,
 278                         char is_duplicate)
 279 {
 280         struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 281         struct hlist_node *node;
 282         int tmp_hna_buff_len;
 283
 284         bat_dbg(DBG_BATMAN, bat_priv, "update_originator(): "
 285                 "Searching and updating originator entry of received packet\n");
 286
 287         rcu_read_lock();
 288         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 289                                  &orig_node->neigh_list, list) {
 290                 if (compare_orig(tmp_neigh_node->addr, ethhdr->h_source) &&
 291                     (tmp_neigh_node->if_incoming == if_incoming)) {
 292                         neigh_node = tmp_neigh_node;
 293                         continue;
 294                 }
 295
 296                 if (is_duplicate)
 297                         continue;
 298
 299                 ring_buffer_set(tmp_neigh_node->tq_recv,
 300                                 &tmp_neigh_node->tq_index, 0);
 301                 tmp_neigh_node->tq_avg =
 302                         ring_buffer_avg(tmp_neigh_node->tq_recv);
 303         }
 304
 305         if (!neigh_node) {
 306                 struct orig_node *orig_tmp;
 307
 308                 orig_tmp = get_orig_node(bat_priv, ethhdr->h_source);
 309                 if (!orig_tmp)
 310                         goto unlock;
 311
 312                 neigh_node = create_neighbor(orig_node, orig_tmp,
 313                                              ethhdr->h_source, if_incoming);
 314
 315                 kref_put(&orig_tmp->refcount, orig_node_free_ref);
 316                 if (!neigh_node)
 317                         goto unlock;
 318         } else
 319                 bat_dbg(DBG_BATMAN, bat_priv,
 320                         "Updating existing last-hop neighbor of originator\n");
 321
 322         kref_get(&neigh_node->refcount);
 323         rcu_read_unlock();
 324
 325         orig_node->flags = batman_packet->flags;
 326         neigh_node->last_valid = jiffies;
 327
 328         ring_buffer_set(neigh_node->tq_recv,
 329                         &neigh_node->tq_index,
 330                         batman_packet->tq);
 331         neigh_node->tq_avg = ring_buffer_avg(neigh_node->tq_recv);
 332
 333         if (!is_duplicate) {
 334                 orig_node->last_ttl = batman_packet->ttl;
 335                 neigh_node->last_ttl = batman_packet->ttl;
 336         }
 337
 338         tmp_hna_buff_len = (hna_buff_len > batman_packet->num_hna * ETH_ALEN ?
 339                             batman_packet->num_hna * ETH_ALEN : hna_buff_len);
 340
 341         /* if this neighbor already is our next hop there is nothing
 342          * to change */
 343         if (orig_node->router == neigh_node)
 344                 goto update_hna;
 345
 346         /* if this neighbor does not offer a better TQ we won't consider it */
 347         if ((orig_node->router) &&
 348             (orig_node->router->tq_avg > neigh_node->tq_avg))
 349                 goto update_hna;
 350
 351         /* if the TQ is the same and the link not more symetric we
 352          * won't consider it either */
 353         if ((orig_node->router) &&
 354              ((neigh_node->tq_avg == orig_node->router->tq_avg) &&
 355              (orig_node->router->orig_node->bcast_own_sum[if_incoming->if_num]
 356               >= neigh_node->orig_node->bcast_own_sum[if_incoming->if_num])))
 357                 goto update_hna;
 358
 359         update_routes(bat_priv, orig_node, neigh_node,
 360                       hna_buff, tmp_hna_buff_len);
 361         goto update_gw;
 362
 363 update_hna:
 364         update_routes(bat_priv, orig_node, orig_node->router,
 365                       hna_buff, tmp_hna_buff_len);
 366
 367 update_gw:
 368         if (orig_node->gw_flags != batman_packet->gw_flags)
 369                 gw_node_update(bat_priv, orig_node, batman_packet->gw_flags);
 370
 371         orig_node->gw_flags = batman_packet->gw_flags;
 372
 373         /* restart gateway selection if fast or late switching was enabled */
 374         if ((orig_node->gw_flags) &&
 375             (atomic_read(&bat_priv->gw_mode) == GW_MODE_CLIENT) &&
 376             (atomic_read(&bat_priv->gw_sel_class) > 2))
 377                 gw_check_election(bat_priv, orig_node);
 378
 379         goto out;
 380
 381 unlock:
 382         rcu_read_unlock();
 383 out:
 384         if (neigh_node)
 385                 kref_put(&neigh_node->refcount, neigh_node_free_ref);
 386 }
 387
 388 /* checks whether the host restarted and is in the protection time.
 389  * returns:
 390  *  0 if the packet is to be accepted
 391  *  1 if the packet is to be ignored.
 392  */
 393 static int window_protected(struct bat_priv *bat_priv,
 394                             int32_t seq_num_diff,
 395                             unsigned long *last_reset)
 396 {
 397         if ((seq_num_diff <= -TQ_LOCAL_WINDOW_SIZE)
 398                 || (seq_num_diff >= EXPECTED_SEQNO_RANGE)) {
 399                 if (time_after(jiffies, *last_reset +
 400                         msecs_to_jiffies(RESET_PROTECTION_MS))) {
 401
 402                         *last_reset = jiffies;
 403                         bat_dbg(DBG_BATMAN, bat_priv,
 404                                 "old packet received, start protection\n");
 405
 406                         return 0;
 407                 } else
 408                         return 1;
 409         }
 410         return 0;
 411 }
 412
 413 /* processes a batman packet for all interfaces, adjusts the sequence number and
 414  * finds out whether it is a duplicate.
 415  * returns:
 416  *   1 the packet is a duplicate
 417  *   0 the packet has not yet been received
 418  *  -1 the packet is old and has been received while the seqno window
 419  *     was protected. Caller should drop it.
 420  */
 421 static char count_real_packets(struct ethhdr *ethhdr,
 422                                struct batman_packet *batman_packet,
 423                                struct batman_if *if_incoming)
 424 {
 425         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 426         struct orig_node *orig_node;
 427         struct neigh_node *tmp_neigh_node;
 428         struct hlist_node *node;
 429         char is_duplicate = 0;
 430         int32_t seq_diff;
 431         int need_update = 0;
 432         int set_mark;
 433
 434         orig_node = get_orig_node(bat_priv, batman_packet->orig);
 435         if (!orig_node)
 436                 return 0;
 437
 438         seq_diff = batman_packet->seqno - orig_node->last_real_seqno;
 439
 440         /* signalize caller that the packet is to be dropped. */
 441         if (window_protected(bat_priv, seq_diff,
 442                              &orig_node->batman_seqno_reset))
 443                 goto err;
 444
 445         rcu_read_lock();
 446         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 447                                  &orig_node->neigh_list, list) {
 448
 449                 is_duplicate |= get_bit_status(tmp_neigh_node->real_bits,
 450                                                orig_node->last_real_seqno,
 451                                                batman_packet->seqno);
 452
 453                 if (compare_orig(tmp_neigh_node->addr, ethhdr->h_source) &&
 454                     (tmp_neigh_node->if_incoming == if_incoming))
 455                         set_mark = 1;
 456                 else
 457                         set_mark = 0;
 458
 459                 /* if the window moved, set the update flag. */
 460                 need_update |= bit_get_packet(bat_priv,
 461                                               tmp_neigh_node->real_bits,
 462                                               seq_diff, set_mark);
 463
 464                 tmp_neigh_node->real_packet_count =
 465                         bit_packet_count(tmp_neigh_node->real_bits);
 466         }
 467         rcu_read_unlock();
 468
 469         if (need_update) {
 470                 bat_dbg(DBG_BATMAN, bat_priv,
 471                         "updating last_seqno: old %d, new %d\n",
 472                         orig_node->last_real_seqno, batman_packet->seqno);
 473                 orig_node->last_real_seqno = batman_packet->seqno;
 474         }
 475
 476         kref_put(&orig_node->refcount, orig_node_free_ref);
 477         return is_duplicate;
 478
 479 err:
 480         kref_put(&orig_node->refcount, orig_node_free_ref);
 481         return -1;
 482 }
 483
 484 /* copy primary address for bonding */
 485 static void mark_bonding_address(struct orig_node *orig_node,
 486                                  struct orig_node *orig_neigh_node,
 487                                  struct batman_packet *batman_packet)
 488
 489 {
 490         if (batman_packet->flags & PRIMARIES_FIRST_HOP)
 491                 memcpy(orig_neigh_node->primary_addr,
 492                        orig_node->orig, ETH_ALEN);
 493
 494         return;
 495 }
 496
 497 /* mark possible bond.candidates in the neighbor list */
 498 void update_bonding_candidates(struct orig_node *orig_node)
 499 {
 500         int candidates;
 501         int interference_candidate;
 502         int best_tq;
 503         struct hlist_node *node, *node2;
 504         struct neigh_node *tmp_neigh_node, *tmp_neigh_node2;
 505         struct neigh_node *first_candidate, *last_candidate;
 506
 507         /* update the candidates for this originator */
 508         if (!orig_node->router) {
 509                 orig_node->bond.candidates = 0;
 510                 return;
 511         }
 512
 513         best_tq = orig_node->router->tq_avg;
 514
 515         /* update bond.candidates */
 516
 517         candidates = 0;
 518
 519         /* mark other nodes which also received "PRIMARIES FIRST HOP" packets
 520          * as "bonding partner" */
 521
 522         /* first, zero the list */
 523         rcu_read_lock();
 524         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 525                                  &orig_node->neigh_list, list) {
 526                 tmp_neigh_node->next_bond_candidate = NULL;
 527         }
 528         rcu_read_unlock();
 529
 530         first_candidate = NULL;
 531         last_candidate = NULL;
 532
 533         rcu_read_lock();
 534         hlist_for_each_entry_rcu(tmp_neigh_node, node,
 535                                  &orig_node->neigh_list, list) {
 536
 537                 /* only consider if it has the same primary address ...  */
 538                 if (memcmp(orig_node->orig,
 539                                 tmp_neigh_node->orig_node->primary_addr,
 540                                 ETH_ALEN) != 0)
 541                         continue;
 542
 543                 /* ... and is good enough to be considered */
 544                 if (tmp_neigh_node->tq_avg < best_tq - BONDING_TQ_THRESHOLD)
 545                         continue;
 546
 547                 /* check if we have another candidate with the same
 548                  * mac address or interface. If we do, we won't
 549                  * select this candidate because of possible interference. */
 550
 551                 interference_candidate = 0;
 552                 hlist_for_each_entry_rcu(tmp_neigh_node2, node2,
 553                                          &orig_node->neigh_list, list) {
 554
 555                         if (tmp_neigh_node2 == tmp_neigh_node)
 556                                 continue;
 557
 558                         /* we only care if the other candidate is even
 559                          * considered as candidate. */
 560                         if (!tmp_neigh_node2->next_bond_candidate)
 561                                 continue;
 562
 563
 564                         if ((tmp_neigh_node->if_incoming ==
 565                                 tmp_neigh_node2->if_incoming)
 566                                 || (memcmp(tmp_neigh_node->addr,
 567                                 tmp_neigh_node2->addr, ETH_ALEN) == 0)) {
 568
 569                                 interference_candidate = 1;
 570                                 break;
 571                         }
 572                 }
 573                 /* don't care further if it is an interference candidate */
 574                 if (interference_candidate)
 575                         continue;
 576
 577                 if (!first_candidate) {
 578                         first_candidate = tmp_neigh_node;
 579                         tmp_neigh_node->next_bond_candidate = first_candidate;
 580                 } else
 581                         tmp_neigh_node->next_bond_candidate = last_candidate;
 582
 583                 last_candidate = tmp_neigh_node;
 584
 585                 candidates++;
 586         }
 587         rcu_read_unlock();
 588
 589         if (candidates > 0) {
 590                 first_candidate->next_bond_candidate = last_candidate;
 591                 orig_node->bond.selected = first_candidate;
 592         }
 593
 594         orig_node->bond.candidates = candidates;
 595 }
 596
 597 void receive_bat_packet(struct ethhdr *ethhdr,
 598                                 struct batman_packet *batman_packet,
 599                                 unsigned char *hna_buff, int hna_buff_len,
 600                                 struct batman_if *if_incoming)
 601 {
 602         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
 603         struct batman_if *batman_if;
 604         struct orig_node *orig_neigh_node, *orig_node;
 605         char has_directlink_flag;
 606         char is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
 607         char is_broadcast = 0, is_bidirectional, is_single_hop_neigh;
 608         char is_duplicate;
 609         uint32_t if_incoming_seqno;
 610
 611         /* Silently drop when the batman packet is actually not a
 612          * correct packet.
 613          *
 614          * This might happen if a packet is padded (e.g. Ethernet has a
 615          * minimum frame length of 64 byte) and the aggregation interprets
 616          * it as an additional length.
 617          *
 618          * TODO: A more sane solution would be to have a bit in the
 619          * batman_packet to detect whether the packet is the last
 620          * packet in an aggregation.  Here we expect that the padding
 621          * is always zero (or not 0x01)
 622          */
 623         if (batman_packet->packet_type != BAT_PACKET)
 624                 return;
 625
 626         /* could be changed by schedule_own_packet() */
 627         if_incoming_seqno = atomic_read(&if_incoming->seqno);
 628
 629         has_directlink_flag = (batman_packet->flags & DIRECTLINK ? 1 : 0);
 630
 631         is_single_hop_neigh = (compare_orig(ethhdr->h_source,
 632                                             batman_packet->orig) ? 1 : 0);
 633
 634         bat_dbg(DBG_BATMAN, bat_priv,
 635                 "Received BATMAN packet via NB: %pM, IF: %s [%pM] "
 636                 "(from OG: %pM, via prev OG: %pM, seqno %d, tq %d, "
 637                 "TTL %d, V %d, IDF %d)\n",
 638                 ethhdr->h_source, if_incoming->net_dev->name,
 639                 if_incoming->net_dev->dev_addr, batman_packet->orig,
 640                 batman_packet->prev_sender, batman_packet->seqno,
 641                 batman_packet->tq, batman_packet->ttl, batman_packet->version,
 642                 has_directlink_flag);
 643
 644         rcu_read_lock();
 645         list_for_each_entry_rcu(batman_if, &if_list, list) {
 646                 if (batman_if->if_status != IF_ACTIVE)
 647                         continue;
 648
 649                 if (batman_if->soft_iface != if_incoming->soft_iface)
 650                         continue;
 651
 652                 if (compare_orig(ethhdr->h_source,
 653                                  batman_if->net_dev->dev_addr))
 654                         is_my_addr = 1;
 655
 656                 if (compare_orig(batman_packet->orig,
 657                                  batman_if->net_dev->dev_addr))
 658                         is_my_orig = 1;
 659
 660                 if (compare_orig(batman_packet->prev_sender,
 661                                  batman_if->net_dev->dev_addr))
 662                         is_my_oldorig = 1;
 663
 664                 if (compare_orig(ethhdr->h_source, broadcast_addr))
 665                         is_broadcast = 1;
 666         }
 667         rcu_read_unlock();
 668
 669         if (batman_packet->version != COMPAT_VERSION) {
 670                 bat_dbg(DBG_BATMAN, bat_priv,
 671                         "Drop packet: incompatible batman version (%i)\n",
 672                         batman_packet->version);
 673                 return;
 674         }
 675
 676         if (is_my_addr) {
 677                 bat_dbg(DBG_BATMAN, bat_priv,
 678                         "Drop packet: received my own broadcast (sender: %pM"
 679                         ")\n",
 680                         ethhdr->h_source);
 681                 return;
 682         }
 683
 684         if (is_broadcast) {
 685                 bat_dbg(DBG_BATMAN, bat_priv, "Drop packet: "
 686                 "ignoring all packets with broadcast source addr (sender: %pM"
 687                 ")\n", ethhdr->h_source);
 688                 return;
 689         }
 690
 691         if (is_my_orig) {
 692                 unsigned long *word;
 693                 int offset;
 694
 695                 orig_neigh_node = get_orig_node(bat_priv, ethhdr->h_source);
 696                 if (!orig_neigh_node)
 697                         return;
 698
 699                 /* neighbor has to indicate direct link and it has to
 700                  * come via the corresponding interface */
 701                 /* if received seqno equals last send seqno save new
 702                  * seqno for bidirectional check */
 703                 if (has_directlink_flag &&
 704                     compare_orig(if_incoming->net_dev->dev_addr,
 705                                  batman_packet->orig) &&
 706                     (batman_packet->seqno - if_incoming_seqno + 2 == 0)) {
 707                         offset = if_incoming->if_num * NUM_WORDS;
 708                         word = &(orig_neigh_node->bcast_own[offset]);
 709                         bit_mark(word, 0);
 710                         orig_neigh_node->bcast_own_sum[if_incoming->if_num] =
 711                                 bit_packet_count(word);
 712                 }
 713
 714                 bat_dbg(DBG_BATMAN, bat_priv, "Drop packet: "
 715                         "originator packet from myself (via neighbor)\n");
 716                 kref_put(&orig_neigh_node->refcount, orig_node_free_ref);
 717                 return;
 718         }
 719
 720         if (is_my_oldorig) {
 721                 bat_dbg(DBG_BATMAN, bat_priv,
 722                         "Drop packet: ignoring all rebroadcast echos (sender: "
 723                         "%pM)\n", ethhdr->h_source);
 724                 return;
 725         }
 726
 727         orig_node = get_orig_node(bat_priv, batman_packet->orig);
 728         if (!orig_node)
 729                 return;
 730
 731         is_duplicate = count_real_packets(ethhdr, batman_packet, if_incoming);
 732
 733         if (is_duplicate == -1) {
 734                 bat_dbg(DBG_BATMAN, bat_priv,
 735                         "Drop packet: packet within seqno protection time "
 736                         "(sender: %pM)\n", ethhdr->h_source);
 737                 goto out;
 738         }
 739
 740         if (batman_packet->tq == 0) {
 741                 bat_dbg(DBG_BATMAN, bat_priv,
 742                         "Drop packet: originator packet with tq equal 0\n");
 743                 goto out;
 744         }
 745
 746         /* avoid temporary routing loops */
 747         if ((orig_node->router) &&
 748             (orig_node->router->orig_node->router) &&
 749             (compare_orig(orig_node->router->addr,
 750                           batman_packet->prev_sender)) &&
 751             !(compare_orig(batman_packet->orig, batman_packet->prev_sender)) &&
 752             (compare_orig(orig_node->router->addr,
 753                           orig_node->router->orig_node->router->addr))) {
 754                 bat_dbg(DBG_BATMAN, bat_priv,
 755                         "Drop packet: ignoring all rebroadcast packets that "
 756                         "may make me loop (sender: %pM)\n", ethhdr->h_source);
 757                 goto out;
 758         }
 759
 760         /* if sender is a direct neighbor the sender mac equals
 761          * originator mac */
 762         orig_neigh_node = (is_single_hop_neigh ?
 763                            orig_node :
 764                            get_orig_node(bat_priv, ethhdr->h_source));
 765         if (!orig_neigh_node)
 766                 goto out_neigh;
 767
 768         /* drop packet if sender is not a direct neighbor and if we
 769          * don't route towards it */
 770         if (!is_single_hop_neigh && (!orig_neigh_node->router)) {
 771                 bat_dbg(DBG_BATMAN, bat_priv,
 772                         "Drop packet: OGM via unknown neighbor!\n");
 773                 goto out_neigh;
 774         }
 775
 776         is_bidirectional = is_bidirectional_neigh(orig_node, orig_neigh_node,
 777                                                 batman_packet, if_incoming);
 778
 779         /* update ranking if it is not a duplicate or has the same
 780          * seqno and similar ttl as the non-duplicate */
 781         if (is_bidirectional &&
 782             (!is_duplicate ||
 783              ((orig_node->last_real_seqno == batman_packet->seqno) &&
 784               (orig_node->last_ttl - 3 <= batman_packet->ttl))))
 785                 update_orig(bat_priv, orig_node, ethhdr, batman_packet,
 786                             if_incoming, hna_buff, hna_buff_len, is_duplicate);
 787
 788         mark_bonding_address(orig_node, orig_neigh_node, batman_packet);
 789         update_bonding_candidates(orig_node);
 790
 791         /* is single hop (direct) neighbor */
 792         if (is_single_hop_neigh) {
 793
 794                 /* mark direct link on incoming interface */
 795                 schedule_forward_packet(orig_node, ethhdr, batman_packet,
 796                                         1, hna_buff_len, if_incoming);
 797
 798                 bat_dbg(DBG_BATMAN, bat_priv, "Forwarding packet: "
 799                         "rebroadcast neighbor packet with direct link flag\n");
 800                 goto out_neigh;
 801         }
 802
 803         /* multihop originator */
 804         if (!is_bidirectional) {
 805                 bat_dbg(DBG_BATMAN, bat_priv,
 806                         "Drop packet: not received via bidirectional link\n");
 807                 goto out_neigh;
 808         }
 809
 810         if (is_duplicate) {
 811                 bat_dbg(DBG_BATMAN, bat_priv,
 812                         "Drop packet: duplicate packet received\n");
 813                 goto out_neigh;
 814         }
 815
 816         bat_dbg(DBG_BATMAN, bat_priv,
 817                 "Forwarding packet: rebroadcast originator packet\n");
 818         schedule_forward_packet(orig_node, ethhdr, batman_packet,
 819                                 0, hna_buff_len, if_incoming);
 820
 821 out_neigh:
 822         if (!is_single_hop_neigh)
 823                 kref_put(&orig_neigh_node->refcount, orig_node_free_ref);
 824 out:
 825         kref_put(&orig_node->refcount, orig_node_free_ref);
 826 }
 827
 828 int recv_bat_packet(struct sk_buff *skb, struct batman_if *batman_if)
 829 {
 830         struct bat_priv *bat_priv = netdev_priv(batman_if->soft_iface);
 831         struct ethhdr *ethhdr;
 832
 833         /* drop packet if it has not necessary minimum size */
 834         if (unlikely(!pskb_may_pull(skb, sizeof(struct batman_packet))))
 835                 return NET_RX_DROP;
 836
 837         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 838
 839         /* packet with broadcast indication but unicast recipient */
 840         if (!is_broadcast_ether_addr(ethhdr->h_dest))
 841                 return NET_RX_DROP;
 842
 843         /* packet with broadcast sender address */
 844         if (is_broadcast_ether_addr(ethhdr->h_source))
 845                 return NET_RX_DROP;
 846
 847         /* create a copy of the skb, if needed, to modify it. */
 848         if (skb_cow(skb, 0) < 0)
 849                 return NET_RX_DROP;
 850
 851         /* keep skb linear */
 852         if (skb_linearize(skb) < 0)
 853                 return NET_RX_DROP;
 854
 855         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 856
 857         spin_lock_bh(&bat_priv->orig_hash_lock);
 858         receive_aggr_bat_packet(ethhdr,
 859                                 skb->data,
 860                                 skb_headlen(skb),
 861                                 batman_if);
 862         spin_unlock_bh(&bat_priv->orig_hash_lock);
 863
 864         kfree_skb(skb);
 865         return NET_RX_SUCCESS;
 866 }
 867
 868 static int recv_my_icmp_packet(struct bat_priv *bat_priv,
 869                                struct sk_buff *skb, size_t icmp_len)
 870 {
 871         struct orig_node *orig_node;
 872         struct icmp_packet_rr *icmp_packet;
 873         struct batman_if *batman_if;
 874         int ret;
 875         uint8_t dstaddr[ETH_ALEN];
 876
 877         icmp_packet = (struct icmp_packet_rr *)skb->data;
 878
 879         /* add data to device queue */
 880         if (icmp_packet->msg_type != ECHO_REQUEST) {
 881                 bat_socket_receive_packet(icmp_packet, icmp_len);
 882                 return NET_RX_DROP;
 883         }
 884
 885         if (!bat_priv->primary_if)
 886                 return NET_RX_DROP;
 887
 888         /* answer echo request (ping) */
 889         /* get routing information */
 890         spin_lock_bh(&bat_priv->orig_hash_lock);
 891         rcu_read_lock();
 892         orig_node = ((struct orig_node *)hash_find(bat_priv->orig_hash,
 893                                                    compare_orig, choose_orig,
 894                                                    icmp_packet->orig));
 895         rcu_read_unlock();
 896         ret = NET_RX_DROP;
 897
 898         if ((orig_node) && (orig_node->router)) {
 899
 900                 /* don't lock while sending the packets ... we therefore
 901                  * copy the required data before sending */
 902                 batman_if = orig_node->router->if_incoming;
 903                 memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 904                 spin_unlock_bh(&bat_priv->orig_hash_lock);
 905
 906                 /* create a copy of the skb, if needed, to modify it. */
 907                 if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
 908                         return NET_RX_DROP;
 909
 910                 icmp_packet = (struct icmp_packet_rr *)skb->data;
 911
 912                 memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
 913                 memcpy(icmp_packet->orig,
 914                        bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN);
 915                 icmp_packet->msg_type = ECHO_REPLY;
 916                 icmp_packet->ttl = TTL;
 917
 918                 send_skb_packet(skb, batman_if, dstaddr);
 919                 ret = NET_RX_SUCCESS;
 920
 921         } else
 922                 spin_unlock_bh(&bat_priv->orig_hash_lock);
 923
 924         return ret;
 925 }
 926
 927 static int recv_icmp_ttl_exceeded(struct bat_priv *bat_priv,
 928                                   struct sk_buff *skb)
 929 {
 930         struct orig_node *orig_node;
 931         struct icmp_packet *icmp_packet;
 932         struct batman_if *batman_if;
 933         int ret;
 934         uint8_t dstaddr[ETH_ALEN];
 935
 936         icmp_packet = (struct icmp_packet *)skb->data;
 937
 938         /* send TTL exceeded if packet is an echo request (traceroute) */
 939         if (icmp_packet->msg_type != ECHO_REQUEST) {
 940                 pr_debug("Warning - can't forward icmp packet from %pM to "
 941                          "%pM: ttl exceeded\n", icmp_packet->orig,
 942                          icmp_packet->dst);
 943                 return NET_RX_DROP;
 944         }
 945
 946         if (!bat_priv->primary_if)
 947                 return NET_RX_DROP;
 948
 949         /* get routing information */
 950         spin_lock_bh(&bat_priv->orig_hash_lock);
 951         rcu_read_lock();
 952         orig_node = ((struct orig_node *)
 953                      hash_find(bat_priv->orig_hash, compare_orig, choose_orig,
 954                                icmp_packet->orig));
 955         rcu_read_unlock();
 956         ret = NET_RX_DROP;
 957
 958         if ((orig_node) && (orig_node->router)) {
 959
 960                 /* don't lock while sending the packets ... we therefore
 961                  * copy the required data before sending */
 962                 batman_if = orig_node->router->if_incoming;
 963                 memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 964                 spin_unlock_bh(&bat_priv->orig_hash_lock);
 965
 966                 /* create a copy of the skb, if needed, to modify it. */
 967                 if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
 968                         return NET_RX_DROP;
 969
 970                 icmp_packet = (struct icmp_packet *) skb->data;
 971
 972                 memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
 973                 memcpy(icmp_packet->orig,
 974                        bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN);
 975                 icmp_packet->msg_type = TTL_EXCEEDED;
 976                 icmp_packet->ttl = TTL;
 977
 978                 send_skb_packet(skb, batman_if, dstaddr);
 979                 ret = NET_RX_SUCCESS;
 980
 981         } else
 982                 spin_unlock_bh(&bat_priv->orig_hash_lock);
 983
 984         return ret;
 985 }
 986
 987
 988 int recv_icmp_packet(struct sk_buff *skb, struct batman_if *recv_if)
 989 {
 990         struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface);
 991         struct icmp_packet_rr *icmp_packet;
 992         struct ethhdr *ethhdr;
 993         struct orig_node *orig_node;
 994         struct batman_if *batman_if;
 995         int hdr_size = sizeof(struct icmp_packet);
 996         int ret;
 997         uint8_t dstaddr[ETH_ALEN];
 998
 999         /**
1000          * we truncate all incoming icmp packets if they don't match our size
1001          */
1002         if (skb->len >= sizeof(struct icmp_packet_rr))
1003                 hdr_size = sizeof(struct icmp_packet_rr);
1004
1005         /* drop packet if it has not necessary minimum size */
1006         if (unlikely(!pskb_may_pull(skb, hdr_size)))
1007                 return NET_RX_DROP;
1008
1009         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1010
1011         /* packet with unicast indication but broadcast recipient */
1012         if (is_broadcast_ether_addr(ethhdr->h_dest))
1013                 return NET_RX_DROP;
1014
1015         /* packet with broadcast sender address */
1016         if (is_broadcast_ether_addr(ethhdr->h_source))
1017                 return NET_RX_DROP;
1018
1019         /* not for me */
1020         if (!is_my_mac(ethhdr->h_dest))
1021                 return NET_RX_DROP;
1022
1023         icmp_packet = (struct icmp_packet_rr *)skb->data;
1024
1025         /* add record route information if not full */
1026         if ((hdr_size == sizeof(struct icmp_packet_rr)) &&
1027             (icmp_packet->rr_cur < BAT_RR_LEN)) {
1028                 memcpy(&(icmp_packet->rr[icmp_packet->rr_cur]),
1029                         ethhdr->h_dest, ETH_ALEN);
1030                 icmp_packet->rr_cur++;
1031         }
1032
1033         /* packet for me */
1034         if (is_my_mac(icmp_packet->dst))
1035                 return recv_my_icmp_packet(bat_priv, skb, hdr_size);
1036
1037         /* TTL exceeded */
1038         if (icmp_packet->ttl < 2)
1039                 return recv_icmp_ttl_exceeded(bat_priv, skb);
1040
1041         ret = NET_RX_DROP;
1042
1043         /* get routing information */
1044         spin_lock_bh(&bat_priv->orig_hash_lock);
1045         rcu_read_lock();
1046         orig_node = ((struct orig_node *)
1047                      hash_find(bat_priv->orig_hash, compare_orig, choose_orig,
1048                                icmp_packet->dst));
1049         rcu_read_unlock();
1050
1051         if ((orig_node) && (orig_node->router)) {
1052
1053                 /* don't lock while sending the packets ... we therefore
1054                  * copy the required data before sending */
1055                 batman_if = orig_node->router->if_incoming;
1056                 memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
1057                 spin_unlock_bh(&bat_priv->orig_hash_lock);
1058
1059                 /* create a copy of the skb, if needed, to modify it. */
1060                 if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
1061                         return NET_RX_DROP;
1062
1063                 icmp_packet = (struct icmp_packet_rr *)skb->data;
1064
1065                 /* decrement ttl */
1066                 icmp_packet->ttl--;
1067
1068                 /* route it */
1069                 send_skb_packet(skb, batman_if, dstaddr);
1070                 ret = NET_RX_SUCCESS;
1071
1072         } else
1073                 spin_unlock_bh(&bat_priv->orig_hash_lock);
1074
1075         return ret;
1076 }
1077
1078 /* find a suitable router for this originator, and use
1079  * bonding if possible. */
1080 struct neigh_node *find_router(struct bat_priv *bat_priv,
1081                                struct orig_node *orig_node,
1082                                struct batman_if *recv_if)
1083 {
1084         struct orig_node *primary_orig_node;
1085         struct orig_node *router_orig;
1086         struct neigh_node *router, *first_candidate, *best_router;
1087         static uint8_t zero_mac[ETH_ALEN] = {0, 0, 0, 0, 0, 0};
1088         int bonding_enabled;
1089
1090         if (!orig_node)
1091                 return NULL;
1092
1093         if (!orig_node->router)
1094                 return NULL;
1095
1096         /* without bonding, the first node should
1097          * always choose the default router. */
1098
1099         bonding_enabled = atomic_read(&bat_priv->bonding);
1100
1101         if ((!recv_if) && (!bonding_enabled))
1102                 return orig_node->router;
1103
1104         router_orig = orig_node->router->orig_node;
1105
1106         /* if we have something in the primary_addr, we can search
1107          * for a potential bonding candidate. */
1108         if (memcmp(router_orig->primary_addr, zero_mac, ETH_ALEN) == 0)
1109                 return orig_node->router;
1110
1111         /* find the orig_node which has the primary interface. might
1112          * even be the same as our router_orig in many cases */
1113
1114         if (memcmp(router_orig->primary_addr,
1115                                 router_orig->orig, ETH_ALEN) == 0) {
1116                 primary_orig_node = router_orig;
1117         } else {
1118                 rcu_read_lock();
1119                 primary_orig_node = hash_find(bat_priv->orig_hash, compare_orig,
1120                                                choose_orig,
1121                                                router_orig->primary_addr);
1122                 rcu_read_unlock();
1123
1124                 if (!primary_orig_node)
1125                         return orig_node->router;
1126         }
1127
1128         /* with less than 2 candidates, we can't do any
1129          * bonding and prefer the original router. */
1130
1131         if (primary_orig_node->bond.candidates < 2)
1132                 return orig_node->router;
1133
1134
1135         /* all nodes between should choose a candidate which
1136          * is is not on the interface where the packet came
1137          * in. */
1138         first_candidate = primary_orig_node->bond.selected;
1139         router = first_candidate;
1140
1141         if (bonding_enabled) {
1142                 /* in the bonding case, send the packets in a round
1143                  * robin fashion over the remaining interfaces. */
1144                 do {
1145                         /* recv_if == NULL on the first node. */
1146                         if (router->if_incoming != recv_if)
1147                                 break;
1148
1149                         router = router->next_bond_candidate;
1150                 } while (router != first_candidate);
1151
1152                 primary_orig_node->bond.selected = router->next_bond_candidate;
1153
1154         } else {
1155                 /* if bonding is disabled, use the best of the
1156                  * remaining candidates which are not using
1157                  * this interface. */
1158                 best_router = first_candidate;
1159
1160                 do {
1161                         /* recv_if == NULL on the first node. */
1162                         if ((router->if_incoming != recv_if) &&
1163                                 (router->tq_avg > best_router->tq_avg))
1164                                         best_router = router;
1165
1166                         router = router->next_bond_candidate;
1167                 } while (router != first_candidate);
1168
1169                 router = best_router;
1170         }
1171
1172         return router;
1173 }
1174
1175 static int check_unicast_packet(struct sk_buff *skb, int hdr_size)
1176 {
1177         struct ethhdr *ethhdr;
1178
1179         /* drop packet if it has not necessary minimum size */
1180         if (unlikely(!pskb_may_pull(skb, hdr_size)))
1181                 return -1;
1182
1183         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1184
1185         /* packet with unicast indication but broadcast recipient */
1186         if (is_broadcast_ether_addr(ethhdr->h_dest))
1187                 return -1;
1188
1189         /* packet with broadcast sender address */
1190         if (is_broadcast_ether_addr(ethhdr->h_source))
1191                 return -1;
1192
1193         /* not for me */
1194         if (!is_my_mac(ethhdr->h_dest))
1195                 return -1;
1196
1197         return 0;
1198 }
1199
1200 int route_unicast_packet(struct sk_buff *skb, struct batman_if *recv_if,
1201                          int hdr_size)
1202 {
1203         struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1204         struct orig_node *orig_node;
1205         struct neigh_node *router;
1206         struct batman_if *batman_if;
1207         uint8_t dstaddr[ETH_ALEN];
1208         struct unicast_packet *unicast_packet;
1209         struct ethhdr *ethhdr = (struct ethhdr *)skb_mac_header(skb);
1210         int ret;
1211         struct sk_buff *new_skb;
1212
1213         unicast_packet = (struct unicast_packet *)skb->data;
1214
1215         /* TTL exceeded */
1216         if (unicast_packet->ttl < 2) {
1217                 pr_debug("Warning - can't forward unicast packet from %pM to "
1218                          "%pM: ttl exceeded\n", ethhdr->h_source,
1219                          unicast_packet->dest);
1220                 return NET_RX_DROP;
1221         }
1222
1223         /* get routing information */
1224         spin_lock_bh(&bat_priv->orig_hash_lock);
1225         rcu_read_lock();
1226         orig_node = ((struct orig_node *)
1227                      hash_find(bat_priv->orig_hash, compare_orig, choose_orig,
1228                                unicast_packet->dest));
1229         rcu_read_unlock();
1230
1231         router = find_router(bat_priv, orig_node, recv_if);
1232
1233         if (!router) {
1234                 spin_unlock_bh(&bat_priv->orig_hash_lock);
1235                 return NET_RX_DROP;
1236         }
1237
1238         /* don't lock while sending the packets ... we therefore
1239          * copy the required data before sending */
1240
1241         batman_if = router->if_incoming;
1242         memcpy(dstaddr, router->addr, ETH_ALEN);
1243
1244         spin_unlock_bh(&bat_priv->orig_hash_lock);
1245
1246         /* create a copy of the skb, if needed, to modify it. */
1247         if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
1248                 return NET_RX_DROP;
1249
1250         unicast_packet = (struct unicast_packet *)skb->data;
1251
1252         if (unicast_packet->packet_type == BAT_UNICAST &&
1253             atomic_read(&bat_priv->fragmentation) &&
1254             skb->len > batman_if->net_dev->mtu)
1255                 return frag_send_skb(skb, bat_priv, batman_if,
1256                                      dstaddr);
1257
1258         if (unicast_packet->packet_type == BAT_UNICAST_FRAG &&
1259             frag_can_reassemble(skb, batman_if->net_dev->mtu)) {
1260
1261                 ret = frag_reassemble_skb(skb, bat_priv, &new_skb);
1262
1263                 if (ret == NET_RX_DROP)
1264                         return NET_RX_DROP;
1265
1266                 /* packet was buffered for late merge */
1267                 if (!new_skb)
1268                         return NET_RX_SUCCESS;
1269
1270                 skb = new_skb;
1271                 unicast_packet = (struct unicast_packet *)skb->data;
1272         }
1273
1274         /* decrement ttl */
1275         unicast_packet->ttl--;
1276
1277         /* route it */
1278         send_skb_packet(skb, batman_if, dstaddr);
1279
1280         return NET_RX_SUCCESS;
1281 }
1282
1283 int recv_unicast_packet(struct sk_buff *skb, struct batman_if *recv_if)
1284 {
1285         struct unicast_packet *unicast_packet;
1286         int hdr_size = sizeof(struct unicast_packet);
1287
1288         if (check_unicast_packet(skb, hdr_size) < 0)
1289                 return NET_RX_DROP;
1290
1291         unicast_packet = (struct unicast_packet *)skb->data;
1292
1293         /* packet for me */
1294         if (is_my_mac(unicast_packet->dest)) {
1295                 interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size);
1296                 return NET_RX_SUCCESS;
1297         }
1298
1299         return route_unicast_packet(skb, recv_if, hdr_size);
1300 }
1301
1302 int recv_ucast_frag_packet(struct sk_buff *skb, struct batman_if *recv_if)
1303 {
1304         struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1305         struct unicast_frag_packet *unicast_packet;
1306         int hdr_size = sizeof(struct unicast_frag_packet);
1307         struct sk_buff *new_skb = NULL;
1308         int ret;
1309
1310         if (check_unicast_packet(skb, hdr_size) < 0)
1311                 return NET_RX_DROP;
1312
1313         unicast_packet = (struct unicast_frag_packet *)skb->data;
1314
1315         /* packet for me */
1316         if (is_my_mac(unicast_packet->dest)) {
1317
1318                 ret = frag_reassemble_skb(skb, bat_priv, &new_skb);
1319
1320                 if (ret == NET_RX_DROP)
1321                         return NET_RX_DROP;
1322
1323                 /* packet was buffered for late merge */
1324                 if (!new_skb)
1325                         return NET_RX_SUCCESS;
1326
1327                 interface_rx(recv_if->soft_iface, new_skb, recv_if,
1328                              sizeof(struct unicast_packet));
1329                 return NET_RX_SUCCESS;
1330         }
1331
1332         return route_unicast_packet(skb, recv_if, hdr_size);
1333 }
1334
1335
1336 int recv_bcast_packet(struct sk_buff *skb, struct batman_if *recv_if)
1337 {
1338         struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1339         struct orig_node *orig_node;
1340         struct bcast_packet *bcast_packet;
1341         struct ethhdr *ethhdr;
1342         int hdr_size = sizeof(struct bcast_packet);
1343         int32_t seq_diff;
1344
1345         /* drop packet if it has not necessary minimum size */
1346         if (unlikely(!pskb_may_pull(skb, hdr_size)))
1347                 return NET_RX_DROP;
1348
1349         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1350
1351         /* packet with broadcast indication but unicast recipient */
1352         if (!is_broadcast_ether_addr(ethhdr->h_dest))
1353                 return NET_RX_DROP;
1354
1355         /* packet with broadcast sender address */
1356         if (is_broadcast_ether_addr(ethhdr->h_source))
1357                 return NET_RX_DROP;
1358
1359         /* ignore broadcasts sent by myself */
1360         if (is_my_mac(ethhdr->h_source))
1361                 return NET_RX_DROP;
1362
1363         bcast_packet = (struct bcast_packet *)skb->data;
1364
1365         /* ignore broadcasts originated by myself */
1366         if (is_my_mac(bcast_packet->orig))
1367                 return NET_RX_DROP;
1368
1369         if (bcast_packet->ttl < 2)
1370                 return NET_RX_DROP;
1371
1372         spin_lock_bh(&bat_priv->orig_hash_lock);
1373         rcu_read_lock();
1374         orig_node = ((struct orig_node *)
1375                      hash_find(bat_priv->orig_hash, compare_orig, choose_orig,
1376                                bcast_packet->orig));
1377         rcu_read_unlock();
1378
1379         if (!orig_node) {
1380                 spin_unlock_bh(&bat_priv->orig_hash_lock);
1381                 return NET_RX_DROP;
1382         }
1383
1384         /* check whether the packet is a duplicate */
1385         if (get_bit_status(orig_node->bcast_bits,
1386                            orig_node->last_bcast_seqno,
1387                            ntohl(bcast_packet->seqno))) {
1388                 spin_unlock_bh(&bat_priv->orig_hash_lock);
1389                 return NET_RX_DROP;
1390         }
1391
1392         seq_diff = ntohl(bcast_packet->seqno) - orig_node->last_bcast_seqno;
1393
1394         /* check whether the packet is old and the host just restarted. */
1395         if (window_protected(bat_priv, seq_diff,
1396                              &orig_node->bcast_seqno_reset)) {
1397                 spin_unlock_bh(&bat_priv->orig_hash_lock);
1398                 return NET_RX_DROP;
1399         }
1400
1401         /* mark broadcast in flood history, update window position
1402          * if required. */
1403         if (bit_get_packet(bat_priv, orig_node->bcast_bits, seq_diff, 1))
1404                 orig_node->last_bcast_seqno = ntohl(bcast_packet->seqno);
1405
1406         spin_unlock_bh(&bat_priv->orig_hash_lock);
1407         /* rebroadcast packet */
1408         add_bcast_packet_to_list(bat_priv, skb);
1409
1410         /* broadcast for me */
1411         interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size);
1412
1413         return NET_RX_SUCCESS;
1414 }
1415
1416 int recv_vis_packet(struct sk_buff *skb, struct batman_if *recv_if)
1417 {
1418         struct vis_packet *vis_packet;
1419         struct ethhdr *ethhdr;
1420         struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1421         int hdr_size = sizeof(struct vis_packet);
1422
1423         /* keep skb linear */
1424         if (skb_linearize(skb) < 0)
1425                 return NET_RX_DROP;
1426
1427         if (unlikely(!pskb_may_pull(skb, hdr_size)))
1428                 return NET_RX_DROP;
1429
1430         vis_packet = (struct vis_packet *)skb->data;
1431         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1432
1433         /* not for me */
1434         if (!is_my_mac(ethhdr->h_dest))
1435                 return NET_RX_DROP;
1436
1437         /* ignore own packets */
1438         if (is_my_mac(vis_packet->vis_orig))
1439                 return NET_RX_DROP;
1440
1441         if (is_my_mac(vis_packet->sender_orig))
1442                 return NET_RX_DROP;
1443
1444         switch (vis_packet->vis_type) {
1445         case VIS_TYPE_SERVER_SYNC:
1446                 receive_server_sync_packet(bat_priv, vis_packet,
1447                                            skb_headlen(skb));
1448                 break;
1449
1450         case VIS_TYPE_CLIENT_UPDATE:
1451                 receive_client_update_packet(bat_priv, vis_packet,
1452                                              skb_headlen(skb));
1453                 break;
1454
1455         default:        /* ignore unknown packet */
1456                 break;
1457         }
1458
1459         /* We take a copy of the data in the packet, so we should
1460            always free the skbuf. */
1461         return NET_RX_DROP;
1462 }