drivers/staging/batman-adv/routing.c

   1 /*
   2  * Copyright (C) 2007-2010 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 "device.h"
  29 #include "translation-table.h"
  30 #include "originator.h"
  31 #include "types.h"
  32 #include "ring_buffer.h"
  33 #include "vis.h"
  34 #include "aggregation.h"
  35
  36 DECLARE_WAIT_QUEUE_HEAD(thread_wait);
  37
  38 void slide_own_bcast_window(struct batman_if *batman_if)
  39 {
  40         HASHIT(hashit);
  41         struct orig_node *orig_node;
  42         TYPE_OF_WORD *word;
  43         unsigned long flags;
  44
  45         spin_lock_irqsave(&orig_hash_lock, flags);
  46
  47         while (hash_iterate(orig_hash, &hashit)) {
  48                 orig_node = hashit.bucket->data;
  49                 word = &(orig_node->bcast_own[batman_if->if_num * NUM_WORDS]);
  50
  51                 bit_get_packet(word, 1, 0);
  52                 orig_node->bcast_own_sum[batman_if->if_num] =
  53                         bit_packet_count(word);
  54         }
  55
  56         spin_unlock_irqrestore(&orig_hash_lock, flags);
  57 }
  58
  59 static void update_HNA(struct orig_node *orig_node,
  60                        unsigned char *hna_buff, int hna_buff_len)
  61 {
  62         if ((hna_buff_len != orig_node->hna_buff_len) ||
  63             ((hna_buff_len > 0) &&
  64              (orig_node->hna_buff_len > 0) &&
  65              (memcmp(orig_node->hna_buff, hna_buff, hna_buff_len) != 0))) {
  66
  67                 if (orig_node->hna_buff_len > 0)
  68                         hna_global_del_orig(orig_node,
  69                                             "originator changed hna");
  70
  71                 if ((hna_buff_len > 0) && (hna_buff != NULL))
  72                         hna_global_add_orig(orig_node, hna_buff, hna_buff_len);
  73         }
  74 }
  75
  76 static void update_route(struct orig_node *orig_node,
  77                          struct neigh_node *neigh_node,
  78                          unsigned char *hna_buff, int hna_buff_len)
  79 {
  80         /* route deleted */
  81         if ((orig_node->router != NULL) && (neigh_node == NULL)) {
  82
  83                 bat_dbg(DBG_ROUTES, "Deleting route towards: %pM\n",
  84                         orig_node->orig);
  85                 hna_global_del_orig(orig_node, "originator timed out");
  86
  87                 /* route added */
  88         } else if ((orig_node->router == NULL) && (neigh_node != NULL)) {
  89
  90                 bat_dbg(DBG_ROUTES,
  91                         "Adding route towards: %pM (via %pM)\n",
  92                         orig_node->orig, neigh_node->addr);
  93                 hna_global_add_orig(orig_node, hna_buff, hna_buff_len);
  94
  95                 /* route changed */
  96         } else {
  97                 bat_dbg(DBG_ROUTES,
  98                         "Changing route towards: %pM "
  99                         "(now via %pM - was via %pM)\n",
 100                         orig_node->orig, neigh_node->addr,
 101                         orig_node->router->addr);
 102         }
 103
 104         orig_node->router = neigh_node;
 105 }
 106
 107
 108 void update_routes(struct orig_node *orig_node,
 109                           struct neigh_node *neigh_node,
 110                           unsigned char *hna_buff, int hna_buff_len)
 111 {
 112
 113         if (orig_node == NULL)
 114                 return;
 115
 116         if (orig_node->router != neigh_node)
 117                 update_route(orig_node, neigh_node, hna_buff, hna_buff_len);
 118         /* may be just HNA changed */
 119         else
 120                 update_HNA(orig_node, hna_buff, hna_buff_len);
 121 }
 122
 123 static int isBidirectionalNeigh(struct orig_node *orig_node,
 124                                 struct orig_node *orig_neigh_node,
 125                                 struct batman_packet *batman_packet,
 126                                 struct batman_if *if_incoming)
 127 {
 128         struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 129         unsigned char total_count;
 130
 131         if (orig_node == orig_neigh_node) {
 132                 list_for_each_entry(tmp_neigh_node,
 133                                     &orig_node->neigh_list,
 134                                     list) {
 135
 136                         if (compare_orig(tmp_neigh_node->addr,
 137                                          orig_neigh_node->orig) &&
 138                             (tmp_neigh_node->if_incoming == if_incoming))
 139                                 neigh_node = tmp_neigh_node;
 140                 }
 141
 142                 if (!neigh_node)
 143                         neigh_node = create_neighbor(orig_node,
 144                                                      orig_neigh_node,
 145                                                      orig_neigh_node->orig,
 146                                                      if_incoming);
 147                 /* create_neighbor failed, return 0 */
 148                 if (!neigh_node)
 149                         return 0;
 150
 151                 neigh_node->last_valid = jiffies;
 152         } else {
 153                 /* find packet count of corresponding one hop neighbor */
 154                 list_for_each_entry(tmp_neigh_node,
 155                                     &orig_neigh_node->neigh_list, list) {
 156
 157                         if (compare_orig(tmp_neigh_node->addr,
 158                                          orig_neigh_node->orig) &&
 159                             (tmp_neigh_node->if_incoming == if_incoming))
 160                                 neigh_node = tmp_neigh_node;
 161                 }
 162
 163                 if (!neigh_node)
 164                         neigh_node = create_neighbor(orig_neigh_node,
 165                                                      orig_neigh_node,
 166                                                      orig_neigh_node->orig,
 167                                                      if_incoming);
 168                 /* create_neighbor failed, return 0 */
 169                 if (!neigh_node)
 170                         return 0;
 171         }
 172
 173         orig_node->last_valid = jiffies;
 174
 175         /* pay attention to not get a value bigger than 100 % */
 176         total_count = (orig_neigh_node->bcast_own_sum[if_incoming->if_num] >
 177                        neigh_node->real_packet_count ?
 178                        neigh_node->real_packet_count :
 179                        orig_neigh_node->bcast_own_sum[if_incoming->if_num]);
 180
 181         /* if we have too few packets (too less data) we set tq_own to zero */
 182         /* if we receive too few packets it is not considered bidirectional */
 183         if ((total_count < TQ_LOCAL_BIDRECT_SEND_MINIMUM) ||
 184             (neigh_node->real_packet_count < TQ_LOCAL_BIDRECT_RECV_MINIMUM))
 185                 orig_neigh_node->tq_own = 0;
 186         else
 187                 /* neigh_node->real_packet_count is never zero as we
 188                  * only purge old information when getting new
 189                  * information */
 190                 orig_neigh_node->tq_own = (TQ_MAX_VALUE * total_count) /
 191                         neigh_node->real_packet_count;
 192
 193         /*
 194          * 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
 195          * affect the nearly-symmetric links only a little, but
 196          * punishes asymmetric links more.  This will give a value
 197          * between 0 and TQ_MAX_VALUE
 198          */
 199         orig_neigh_node->tq_asym_penalty =
 200                 TQ_MAX_VALUE -
 201                 (TQ_MAX_VALUE *
 202                  (TQ_LOCAL_WINDOW_SIZE - neigh_node->real_packet_count) *
 203                  (TQ_LOCAL_WINDOW_SIZE - neigh_node->real_packet_count) *
 204                  (TQ_LOCAL_WINDOW_SIZE - neigh_node->real_packet_count)) /
 205                 (TQ_LOCAL_WINDOW_SIZE *
 206                  TQ_LOCAL_WINDOW_SIZE *
 207                  TQ_LOCAL_WINDOW_SIZE);
 208
 209         batman_packet->tq = ((batman_packet->tq *
 210                               orig_neigh_node->tq_own *
 211                               orig_neigh_node->tq_asym_penalty) /
 212                              (TQ_MAX_VALUE * TQ_MAX_VALUE));
 213
 214         bat_dbg(DBG_BATMAN,
 215                 "bidirectional: "
 216                 "orig = %-15pM neigh = %-15pM => own_bcast = %2i, "
 217                 "real recv = %2i, local tq: %3i, asym_penalty: %3i, "
 218                 "total tq: %3i\n",
 219                 orig_node->orig, orig_neigh_node->orig, total_count,
 220                 neigh_node->real_packet_count, orig_neigh_node->tq_own,
 221                 orig_neigh_node->tq_asym_penalty, batman_packet->tq);
 222
 223         /* if link has the minimum required transmission quality
 224          * consider it bidirectional */
 225         if (batman_packet->tq >= TQ_TOTAL_BIDRECT_LIMIT)
 226                 return 1;
 227
 228         return 0;
 229 }
 230
 231 static void update_orig(struct orig_node *orig_node, struct ethhdr *ethhdr,
 232                         struct batman_packet *batman_packet,
 233                         struct batman_if *if_incoming,
 234                         unsigned char *hna_buff, int hna_buff_len,
 235                         char is_duplicate)
 236 {
 237         struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 238         int tmp_hna_buff_len;
 239
 240         bat_dbg(DBG_BATMAN, "update_originator(): "
 241                 "Searching and updating originator entry of received packet\n");
 242
 243         list_for_each_entry(tmp_neigh_node, &orig_node->neigh_list, list) {
 244                 if (compare_orig(tmp_neigh_node->addr, ethhdr->h_source) &&
 245                     (tmp_neigh_node->if_incoming == if_incoming)) {
 246                         neigh_node = tmp_neigh_node;
 247                         continue;
 248                 }
 249
 250                 if (is_duplicate)
 251                         continue;
 252
 253                 ring_buffer_set(tmp_neigh_node->tq_recv,
 254                                 &tmp_neigh_node->tq_index, 0);
 255                 tmp_neigh_node->tq_avg =
 256                         ring_buffer_avg(tmp_neigh_node->tq_recv);
 257         }
 258
 259         if (!neigh_node) {
 260                 struct orig_node *orig_tmp;
 261
 262                 orig_tmp = get_orig_node(ethhdr->h_source);
 263                 if (!orig_tmp)
 264                         return;
 265
 266                 neigh_node = create_neighbor(orig_node,
 267                                              orig_tmp,
 268                                              ethhdr->h_source, if_incoming);
 269                 if (!neigh_node)
 270                         return;
 271         } else
 272                 bat_dbg(DBG_BATMAN,
 273                         "Updating existing last-hop neighbor of originator\n");
 274
 275         orig_node->flags = batman_packet->flags;
 276         neigh_node->last_valid = jiffies;
 277
 278         ring_buffer_set(neigh_node->tq_recv,
 279                         &neigh_node->tq_index,
 280                         batman_packet->tq);
 281         neigh_node->tq_avg = ring_buffer_avg(neigh_node->tq_recv);
 282
 283         if (!is_duplicate) {
 284                 orig_node->last_ttl = batman_packet->ttl;
 285                 neigh_node->last_ttl = batman_packet->ttl;
 286         }
 287
 288         tmp_hna_buff_len = (hna_buff_len > batman_packet->num_hna * ETH_ALEN ?
 289                             batman_packet->num_hna * ETH_ALEN : hna_buff_len);
 290
 291         /* if this neighbor already is our next hop there is nothing
 292          * to change */
 293         if (orig_node->router == neigh_node)
 294                 goto update_hna;
 295
 296         /* if this neighbor does not offer a better TQ we won't consider it */
 297         if ((orig_node->router) &&
 298             (orig_node->router->tq_avg > neigh_node->tq_avg))
 299                 goto update_hna;
 300
 301         /* if the TQ is the same and the link not more symetric we
 302          * won't consider it either */
 303         if ((orig_node->router) &&
 304              ((neigh_node->tq_avg == orig_node->router->tq_avg) &&
 305              (orig_node->router->orig_node->bcast_own_sum[if_incoming->if_num]
 306               >= neigh_node->orig_node->bcast_own_sum[if_incoming->if_num])))
 307                 goto update_hna;
 308
 309         update_routes(orig_node, neigh_node, hna_buff, tmp_hna_buff_len);
 310         return;
 311
 312 update_hna:
 313         update_routes(orig_node, orig_node->router, hna_buff, tmp_hna_buff_len);
 314 }
 315
 316 /* checks whether the host restarted and is in the protection time.
 317  * returns:
 318  *  0 if the packet is to be accepted
 319  *  1 if the packet is to be ignored.
 320  */
 321 static int window_protected(int16_t seq_num_diff,
 322                                 unsigned long *last_reset)
 323 {
 324         if ((seq_num_diff <= -TQ_LOCAL_WINDOW_SIZE)
 325                 || (seq_num_diff >= EXPECTED_SEQNO_RANGE)) {
 326                 if (time_after(jiffies, *last_reset +
 327                         msecs_to_jiffies(RESET_PROTECTION_MS))) {
 328
 329                         *last_reset = jiffies;
 330                         bat_dbg(DBG_BATMAN,
 331                                 "old packet received, start protection\n");
 332
 333                         return 0;
 334                 } else
 335                         return 1;
 336         }
 337         return 0;
 338 }
 339
 340 /* processes a batman packet for all interfaces, adjusts the sequence number and
 341  * finds out whether it is a duplicate.
 342  * returns:
 343  *   1 the packet is a duplicate
 344  *   0 the packet has not yet been received
 345  *  -1 the packet is old and has been received while the seqno window
 346  *     was protected. Caller should drop it.
 347  */
 348 static char count_real_packets(struct ethhdr *ethhdr,
 349                                struct batman_packet *batman_packet,
 350                                struct batman_if *if_incoming)
 351 {
 352         struct orig_node *orig_node;
 353         struct neigh_node *tmp_neigh_node;
 354         char is_duplicate = 0;
 355         int16_t seq_diff;
 356         int need_update = 0;
 357         int set_mark;
 358
 359         orig_node = get_orig_node(batman_packet->orig);
 360         if (orig_node == NULL)
 361                 return 0;
 362
 363         seq_diff = batman_packet->seqno - orig_node->last_real_seqno;
 364
 365         /* signalize caller that the packet is to be dropped. */
 366         if (window_protected(seq_diff, &orig_node->batman_seqno_reset))
 367                 return -1;
 368
 369         list_for_each_entry(tmp_neigh_node, &orig_node->neigh_list, list) {
 370
 371                 is_duplicate |= get_bit_status(tmp_neigh_node->real_bits,
 372                                                orig_node->last_real_seqno,
 373                                                batman_packet->seqno);
 374
 375                 if (compare_orig(tmp_neigh_node->addr, ethhdr->h_source) &&
 376                     (tmp_neigh_node->if_incoming == if_incoming))
 377                         set_mark = 1;
 378                 else
 379                         set_mark = 0;
 380
 381                 /* if the window moved, set the update flag. */
 382                 need_update |= bit_get_packet(tmp_neigh_node->real_bits,
 383                                                 seq_diff, set_mark);
 384
 385                 tmp_neigh_node->real_packet_count =
 386                         bit_packet_count(tmp_neigh_node->real_bits);
 387         }
 388
 389         if (need_update) {
 390                 bat_dbg(DBG_BATMAN, "updating last_seqno: old %d, new %d\n",
 391                         orig_node->last_real_seqno, batman_packet->seqno);
 392                 orig_node->last_real_seqno = batman_packet->seqno;
 393         }
 394
 395         return is_duplicate;
 396 }
 397
 398 void receive_bat_packet(struct ethhdr *ethhdr,
 399                                 struct batman_packet *batman_packet,
 400                                 unsigned char *hna_buff, int hna_buff_len,
 401                                 struct batman_if *if_incoming)
 402 {
 403         struct batman_if *batman_if;
 404         struct orig_node *orig_neigh_node, *orig_node;
 405         char has_directlink_flag;
 406         char is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
 407         char is_broadcast = 0, is_bidirectional, is_single_hop_neigh;
 408         char is_duplicate;
 409         unsigned short if_incoming_seqno;
 410
 411         /* Silently drop when the batman packet is actually not a
 412          * correct packet.
 413          *
 414          * This might happen if a packet is padded (e.g. Ethernet has a
 415          * minimum frame length of 64 byte) and the aggregation interprets
 416          * it as an additional length.
 417          *
 418          * TODO: A more sane solution would be to have a bit in the
 419          * batman_packet to detect whether the packet is the last
 420          * packet in an aggregation.  Here we expect that the padding
 421          * is always zero (or not 0x01)
 422          */
 423         if (batman_packet->packet_type != BAT_PACKET)
 424                 return;
 425
 426         /* could be changed by schedule_own_packet() */
 427         if_incoming_seqno = atomic_read(&if_incoming->seqno);
 428
 429         has_directlink_flag = (batman_packet->flags & DIRECTLINK ? 1 : 0);
 430
 431         is_single_hop_neigh = (compare_orig(ethhdr->h_source,
 432                                             batman_packet->orig) ? 1 : 0);
 433
 434         bat_dbg(DBG_BATMAN, "Received BATMAN packet via NB: %pM, IF: %s [%s] "
 435                 "(from OG: %pM, via prev OG: %pM, seqno %d, tq %d, "
 436                 "TTL %d, V %d, IDF %d)\n",
 437                 ethhdr->h_source, if_incoming->dev, if_incoming->addr_str,
 438                 batman_packet->orig, batman_packet->prev_sender,
 439                 batman_packet->seqno, batman_packet->tq, batman_packet->ttl,
 440                 batman_packet->version, has_directlink_flag);
 441
 442         list_for_each_entry_rcu(batman_if, &if_list, list) {
 443                 if (batman_if->if_status != IF_ACTIVE)
 444                         continue;
 445
 446                 if (compare_orig(ethhdr->h_source,
 447                                  batman_if->net_dev->dev_addr))
 448                         is_my_addr = 1;
 449
 450                 if (compare_orig(batman_packet->orig,
 451                                  batman_if->net_dev->dev_addr))
 452                         is_my_orig = 1;
 453
 454                 if (compare_orig(batman_packet->prev_sender,
 455                                  batman_if->net_dev->dev_addr))
 456                         is_my_oldorig = 1;
 457
 458                 if (compare_orig(ethhdr->h_source, broadcastAddr))
 459                         is_broadcast = 1;
 460         }
 461
 462         if (batman_packet->version != COMPAT_VERSION) {
 463                 bat_dbg(DBG_BATMAN,
 464                         "Drop packet: incompatible batman version (%i)\n",
 465                         batman_packet->version);
 466                 return;
 467         }
 468
 469         if (is_my_addr) {
 470                 bat_dbg(DBG_BATMAN,
 471                         "Drop packet: received my own broadcast (sender: %pM"
 472                         ")\n",
 473                         ethhdr->h_source);
 474                 return;
 475         }
 476
 477         if (is_broadcast) {
 478                 bat_dbg(DBG_BATMAN, "Drop packet: "
 479                 "ignoring all packets with broadcast source addr (sender: %pM"
 480                 ")\n", ethhdr->h_source);
 481                 return;
 482         }
 483
 484         if (is_my_orig) {
 485                 TYPE_OF_WORD *word;
 486                 int offset;
 487
 488                 orig_neigh_node = get_orig_node(ethhdr->h_source);
 489
 490                 if (!orig_neigh_node)
 491                         return;
 492
 493                 /* neighbor has to indicate direct link and it has to
 494                  * come via the corresponding interface */
 495                 /* if received seqno equals last send seqno save new
 496                  * seqno for bidirectional check */
 497                 if (has_directlink_flag &&
 498                     compare_orig(if_incoming->net_dev->dev_addr,
 499                                  batman_packet->orig) &&
 500                     (batman_packet->seqno - if_incoming_seqno + 2 == 0)) {
 501                         offset = if_incoming->if_num * NUM_WORDS;
 502                         word = &(orig_neigh_node->bcast_own[offset]);
 503                         bit_mark(word, 0);
 504                         orig_neigh_node->bcast_own_sum[if_incoming->if_num] =
 505                                 bit_packet_count(word);
 506                 }
 507
 508                 bat_dbg(DBG_BATMAN, "Drop packet: "
 509                         "originator packet from myself (via neighbor)\n");
 510                 return;
 511         }
 512
 513         if (is_my_oldorig) {
 514                 bat_dbg(DBG_BATMAN,
 515                         "Drop packet: ignoring all rebroadcast echos (sender: "
 516                         "%pM)\n", ethhdr->h_source);
 517                 return;
 518         }
 519
 520         orig_node = get_orig_node(batman_packet->orig);
 521         if (orig_node == NULL)
 522                 return;
 523
 524         is_duplicate = count_real_packets(ethhdr, batman_packet, if_incoming);
 525
 526         if (is_duplicate == -1) {
 527                 bat_dbg(DBG_BATMAN,
 528                         "Drop packet: packet within seqno protection time "
 529                         "(sender: %pM)\n", ethhdr->h_source);
 530                 return;
 531         }
 532
 533         if (batman_packet->tq == 0) {
 534                 bat_dbg(DBG_BATMAN,
 535                         "Drop packet: originator packet with tq equal 0\n");
 536                 return;
 537         }
 538
 539         /* avoid temporary routing loops */
 540         if ((orig_node->router) &&
 541             (orig_node->router->orig_node->router) &&
 542             (compare_orig(orig_node->router->addr,
 543                           batman_packet->prev_sender)) &&
 544             !(compare_orig(batman_packet->orig, batman_packet->prev_sender)) &&
 545             (compare_orig(orig_node->router->addr,
 546                           orig_node->router->orig_node->router->addr))) {
 547                 bat_dbg(DBG_BATMAN,
 548                         "Drop packet: ignoring all rebroadcast packets that "
 549                         "may make me loop (sender: %pM)\n", ethhdr->h_source);
 550                 return;
 551         }
 552
 553         /* if sender is a direct neighbor the sender mac equals
 554          * originator mac */
 555         orig_neigh_node = (is_single_hop_neigh ?
 556                            orig_node : get_orig_node(ethhdr->h_source));
 557         if (orig_neigh_node == NULL)
 558                 return;
 559
 560         /* drop packet if sender is not a direct neighbor and if we
 561          * don't route towards it */
 562         if (!is_single_hop_neigh &&
 563             (orig_neigh_node->router == NULL)) {
 564                 bat_dbg(DBG_BATMAN, "Drop packet: OGM via unknown neighbor!\n");
 565                 return;
 566         }
 567
 568         is_bidirectional = isBidirectionalNeigh(orig_node, orig_neigh_node,
 569                                                 batman_packet, if_incoming);
 570
 571         /* update ranking if it is not a duplicate or has the same
 572          * seqno and similar ttl as the non-duplicate */
 573         if (is_bidirectional &&
 574             (!is_duplicate ||
 575              ((orig_node->last_real_seqno == batman_packet->seqno) &&
 576               (orig_node->last_ttl - 3 <= batman_packet->ttl))))
 577                 update_orig(orig_node, ethhdr, batman_packet,
 578                             if_incoming, hna_buff, hna_buff_len, is_duplicate);
 579
 580         /* is single hop (direct) neighbor */
 581         if (is_single_hop_neigh) {
 582
 583                 /* mark direct link on incoming interface */
 584                 schedule_forward_packet(orig_node, ethhdr, batman_packet,
 585                                         1, hna_buff_len, if_incoming);
 586
 587                 bat_dbg(DBG_BATMAN, "Forwarding packet: "
 588                         "rebroadcast neighbor packet with direct link flag\n");
 589                 return;
 590         }
 591
 592         /* multihop originator */
 593         if (!is_bidirectional) {
 594                 bat_dbg(DBG_BATMAN,
 595                         "Drop packet: not received via bidirectional link\n");
 596                 return;
 597         }
 598
 599         if (is_duplicate) {
 600                 bat_dbg(DBG_BATMAN, "Drop packet: duplicate packet received\n");
 601                 return;
 602         }
 603
 604         bat_dbg(DBG_BATMAN,
 605                 "Forwarding packet: rebroadcast originator packet\n");
 606         schedule_forward_packet(orig_node, ethhdr, batman_packet,
 607                                 0, hna_buff_len, if_incoming);
 608 }
 609
 610 int recv_bat_packet(struct sk_buff *skb,
 611                                 struct batman_if *batman_if)
 612 {
 613         struct ethhdr *ethhdr;
 614         unsigned long flags;
 615         struct sk_buff *skb_old;
 616
 617         /* drop packet if it has not necessary minimum size */
 618         if (skb_headlen(skb) < sizeof(struct batman_packet))
 619                 return NET_RX_DROP;
 620
 621         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 622
 623         /* packet with broadcast indication but unicast recipient */
 624         if (!is_bcast(ethhdr->h_dest))
 625                 return NET_RX_DROP;
 626
 627         /* packet with broadcast sender address */
 628         if (is_bcast(ethhdr->h_source))
 629                 return NET_RX_DROP;
 630
 631         /* TODO: we use headlen instead of "length", because
 632          * only this data is paged in. */
 633
 634         /* create a copy of the skb, if needed, to modify it. */
 635         if (!skb_clone_writable(skb, skb_headlen(skb))) {
 636                 skb_old = skb;
 637                 skb = skb_copy(skb, GFP_ATOMIC);
 638                 if (!skb)
 639                         return NET_RX_DROP;
 640                 ethhdr = (struct ethhdr *)skb_mac_header(skb);
 641                 kfree_skb(skb_old);
 642         }
 643
 644         spin_lock_irqsave(&orig_hash_lock, flags);
 645         receive_aggr_bat_packet(ethhdr,
 646                                 skb->data,
 647                                 skb_headlen(skb),
 648                                 batman_if);
 649         spin_unlock_irqrestore(&orig_hash_lock, flags);
 650
 651         kfree_skb(skb);
 652         return NET_RX_SUCCESS;
 653 }
 654
 655 static int recv_my_icmp_packet(struct sk_buff *skb)
 656 {
 657         struct orig_node *orig_node;
 658         struct icmp_packet *icmp_packet;
 659         struct ethhdr *ethhdr;
 660         struct sk_buff *skb_old;
 661         struct batman_if *batman_if;
 662         int ret;
 663         unsigned long flags;
 664         uint8_t dstaddr[ETH_ALEN];
 665
 666         icmp_packet = (struct icmp_packet *)skb->data;
 667         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 668
 669         /* add data to device queue */
 670         if (icmp_packet->msg_type != ECHO_REQUEST) {
 671                 bat_device_receive_packet(icmp_packet);
 672                 return NET_RX_DROP;
 673         }
 674
 675         /* answer echo request (ping) */
 676         /* get routing information */
 677         spin_lock_irqsave(&orig_hash_lock, flags);
 678         orig_node = ((struct orig_node *)hash_find(orig_hash,
 679                                                    icmp_packet->orig));
 680         ret = NET_RX_DROP;
 681
 682         if ((orig_node != NULL) &&
 683             (orig_node->router != NULL)) {
 684
 685                 /* don't lock while sending the packets ... we therefore
 686                  * copy the required data before sending */
 687                 batman_if = orig_node->router->if_incoming;
 688                 memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 689                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 690
 691                 /* create a copy of the skb, if needed, to modify it. */
 692                 skb_old = NULL;
 693                 if (!skb_clone_writable(skb, sizeof(struct icmp_packet))) {
 694                         skb_old = skb;
 695                         skb = skb_copy(skb, GFP_ATOMIC);
 696                         if (!skb)
 697                                 return NET_RX_DROP;
 698
 699                         icmp_packet = (struct icmp_packet *)skb->data;
 700                         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 701                         kfree_skb(skb_old);
 702                 }
 703
 704                 memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
 705                 memcpy(icmp_packet->orig, ethhdr->h_dest, ETH_ALEN);
 706                 icmp_packet->msg_type = ECHO_REPLY;
 707                 icmp_packet->ttl = TTL;
 708
 709                 send_skb_packet(skb, batman_if, dstaddr);
 710                 ret = NET_RX_SUCCESS;
 711
 712         } else
 713                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 714
 715         return ret;
 716 }
 717
 718 static int recv_icmp_ttl_exceeded(struct sk_buff *skb)
 719 {
 720         struct orig_node *orig_node;
 721         struct icmp_packet *icmp_packet;
 722         struct ethhdr *ethhdr;
 723         struct sk_buff *skb_old;
 724         struct batman_if *batman_if;
 725         int ret;
 726         unsigned long flags;
 727         uint8_t dstaddr[ETH_ALEN];
 728
 729         icmp_packet = (struct icmp_packet *)skb->data;
 730         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 731
 732         /* send TTL exceeded if packet is an echo request (traceroute) */
 733         if (icmp_packet->msg_type != ECHO_REQUEST) {
 734                 printk(KERN_WARNING "batman-adv:"
 735                        "Warning - can't forward icmp packet from %pM to %pM: "
 736                        "ttl exceeded\n",
 737                        icmp_packet->orig, icmp_packet->dst);
 738                 return NET_RX_DROP;
 739         }
 740
 741         /* get routing information */
 742         spin_lock_irqsave(&orig_hash_lock, flags);
 743         orig_node = ((struct orig_node *)
 744                      hash_find(orig_hash, icmp_packet->orig));
 745         ret = NET_RX_DROP;
 746
 747         if ((orig_node != NULL) &&
 748             (orig_node->router != NULL)) {
 749
 750                 /* don't lock while sending the packets ... we therefore
 751                  * copy the required data before sending */
 752                 batman_if = orig_node->router->if_incoming;
 753                 memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 754                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 755
 756                 /* create a copy of the skb, if needed, to modify it. */
 757                 if (!skb_clone_writable(skb, sizeof(struct icmp_packet))) {
 758                         skb_old = skb;
 759                         skb = skb_copy(skb, GFP_ATOMIC);
 760                         if (!skb)
 761                                 return NET_RX_DROP;
 762                         icmp_packet = (struct icmp_packet *) skb->data;
 763                         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 764                         kfree_skb(skb_old);
 765                 }
 766
 767                 memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
 768                 memcpy(icmp_packet->orig, ethhdr->h_dest, ETH_ALEN);
 769                 icmp_packet->msg_type = TTL_EXCEEDED;
 770                 icmp_packet->ttl = TTL;
 771
 772                 send_skb_packet(skb, batman_if, dstaddr);
 773                 ret = NET_RX_SUCCESS;
 774
 775         } else
 776                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 777
 778         return ret;
 779 }
 780
 781
 782 int recv_icmp_packet(struct sk_buff *skb)
 783 {
 784         struct icmp_packet *icmp_packet;
 785         struct ethhdr *ethhdr;
 786         struct orig_node *orig_node;
 787         struct sk_buff *skb_old;
 788         struct batman_if *batman_if;
 789         int hdr_size = sizeof(struct icmp_packet);
 790         int ret;
 791         unsigned long flags;
 792         uint8_t dstaddr[ETH_ALEN];
 793
 794         /* drop packet if it has not necessary minimum size */
 795         if (skb_headlen(skb) < hdr_size)
 796                 return NET_RX_DROP;
 797
 798         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 799
 800         /* packet with unicast indication but broadcast recipient */
 801         if (is_bcast(ethhdr->h_dest))
 802                 return NET_RX_DROP;
 803
 804         /* packet with broadcast sender address */
 805         if (is_bcast(ethhdr->h_source))
 806                 return NET_RX_DROP;
 807
 808         /* not for me */
 809         if (!is_my_mac(ethhdr->h_dest))
 810                 return NET_RX_DROP;
 811
 812         icmp_packet = (struct icmp_packet *)skb->data;
 813
 814         /* packet for me */
 815         if (is_my_mac(icmp_packet->dst))
 816                 return recv_my_icmp_packet(skb);
 817
 818         /* TTL exceeded */
 819         if (icmp_packet->ttl < 2)
 820                 return recv_icmp_ttl_exceeded(skb);
 821
 822         ret = NET_RX_DROP;
 823
 824         /* get routing information */
 825         spin_lock_irqsave(&orig_hash_lock, flags);
 826         orig_node = ((struct orig_node *)
 827                      hash_find(orig_hash, icmp_packet->dst));
 828
 829         if ((orig_node != NULL) &&
 830             (orig_node->router != NULL)) {
 831
 832                 /* don't lock while sending the packets ... we therefore
 833                  * copy the required data before sending */
 834                 batman_if = orig_node->router->if_incoming;
 835                 memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 836                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 837
 838                 /* create a copy of the skb, if needed, to modify it. */
 839                 if (!skb_clone_writable(skb, sizeof(struct icmp_packet))) {
 840                         skb_old = skb;
 841                         skb = skb_copy(skb, GFP_ATOMIC);
 842                         if (!skb)
 843                                 return NET_RX_DROP;
 844                         icmp_packet = (struct icmp_packet *)skb->data;
 845                         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 846                         kfree_skb(skb_old);
 847                 }
 848
 849                 /* decrement ttl */
 850                 icmp_packet->ttl--;
 851
 852                 /* route it */
 853                 send_skb_packet(skb, batman_if, dstaddr);
 854                 ret = NET_RX_SUCCESS;
 855
 856         } else
 857                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 858
 859         return ret;
 860 }
 861
 862 int recv_unicast_packet(struct sk_buff *skb)
 863 {
 864         struct unicast_packet *unicast_packet;
 865         struct orig_node *orig_node;
 866         struct ethhdr *ethhdr;
 867         struct batman_if *batman_if;
 868         struct sk_buff *skb_old;
 869         uint8_t dstaddr[ETH_ALEN];
 870         int hdr_size = sizeof(struct unicast_packet);
 871         int ret;
 872         unsigned long flags;
 873
 874         /* drop packet if it has not necessary minimum size */
 875         if (skb_headlen(skb) < hdr_size)
 876                 return NET_RX_DROP;
 877
 878         ethhdr = (struct ethhdr *) skb_mac_header(skb);
 879
 880         /* packet with unicast indication but broadcast recipient */
 881         if (is_bcast(ethhdr->h_dest))
 882                 return NET_RX_DROP;
 883
 884         /* packet with broadcast sender address */
 885         if (is_bcast(ethhdr->h_source))
 886                 return NET_RX_DROP;
 887
 888         /* not for me */
 889         if (!is_my_mac(ethhdr->h_dest))
 890                 return NET_RX_DROP;
 891
 892         unicast_packet = (struct unicast_packet *) skb->data;
 893
 894         /* packet for me */
 895         if (is_my_mac(unicast_packet->dest)) {
 896                 interface_rx(skb, hdr_size);
 897                 return NET_RX_SUCCESS;
 898         }
 899
 900         /* TTL exceeded */
 901         if (unicast_packet->ttl < 2) {
 902                 printk(KERN_WARNING "batman-adv:Warning - "
 903                        "can't forward unicast packet from %pM to %pM: "
 904                        "ttl exceeded\n",
 905                        ethhdr->h_source, unicast_packet->dest);
 906                 return NET_RX_DROP;
 907         }
 908
 909         ret = NET_RX_DROP;
 910         /* get routing information */
 911         spin_lock_irqsave(&orig_hash_lock, flags);
 912         orig_node = ((struct orig_node *)
 913                      hash_find(orig_hash, unicast_packet->dest));
 914
 915         if ((orig_node != NULL) &&
 916             (orig_node->router != NULL)) {
 917
 918                 /* don't lock while sending the packets ... we therefore
 919                  * copy the required data before sending */
 920                 batman_if = orig_node->router->if_incoming;
 921                 memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 922                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 923
 924                 /* create a copy of the skb, if needed, to modify it. */
 925                 if (!skb_clone_writable(skb, sizeof(struct unicast_packet))) {
 926                         skb_old = skb;
 927                         skb = skb_copy(skb, GFP_ATOMIC);
 928                         if (!skb)
 929                                 return NET_RX_DROP;
 930                         unicast_packet = (struct unicast_packet *)skb->data;
 931                         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 932                         kfree_skb(skb_old);
 933                 }
 934                 /* decrement ttl */
 935                 unicast_packet->ttl--;
 936
 937                 /* route it */
 938                 send_skb_packet(skb, batman_if, dstaddr);
 939                 ret = NET_RX_SUCCESS;
 940
 941         } else
 942                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 943
 944         return ret;
 945 }
 946
 947 int recv_bcast_packet(struct sk_buff *skb)
 948 {
 949         struct orig_node *orig_node;
 950         struct bcast_packet *bcast_packet;
 951         struct ethhdr *ethhdr;
 952         int hdr_size = sizeof(struct bcast_packet);
 953         int16_t seq_diff;
 954         unsigned long flags;
 955
 956         /* drop packet if it has not necessary minimum size */
 957         if (skb_headlen(skb) < hdr_size)
 958                 return NET_RX_DROP;
 959
 960         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 961
 962         /* packet with broadcast indication but unicast recipient */
 963         if (!is_bcast(ethhdr->h_dest))
 964                 return NET_RX_DROP;
 965
 966         /* packet with broadcast sender address */
 967         if (is_bcast(ethhdr->h_source))
 968                 return NET_RX_DROP;
 969
 970         /* ignore broadcasts sent by myself */
 971         if (is_my_mac(ethhdr->h_source))
 972                 return NET_RX_DROP;
 973
 974         bcast_packet = (struct bcast_packet *)skb->data;
 975
 976         /* ignore broadcasts originated by myself */
 977         if (is_my_mac(bcast_packet->orig))
 978                 return NET_RX_DROP;
 979
 980         spin_lock_irqsave(&orig_hash_lock, flags);
 981         orig_node = ((struct orig_node *)
 982                      hash_find(orig_hash, bcast_packet->orig));
 983
 984         if (orig_node == NULL) {
 985                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 986                 return NET_RX_DROP;
 987         }
 988
 989         /* check whether the packet is a duplicate */
 990         if (get_bit_status(orig_node->bcast_bits,
 991                            orig_node->last_bcast_seqno,
 992                            ntohs(bcast_packet->seqno))) {
 993                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 994                 return NET_RX_DROP;
 995         }
 996
 997         seq_diff = ntohs(bcast_packet->seqno) - orig_node->last_bcast_seqno;
 998
 999         /* check whether the packet is old and the host just restarted. */
1000         if (window_protected(seq_diff, &orig_node->bcast_seqno_reset)) {
1001                 spin_unlock_irqrestore(&orig_hash_lock, flags);
1002                 return NET_RX_DROP;
1003         }
1004
1005         /* mark broadcast in flood history, update window position
1006          * if required. */
1007         if (bit_get_packet(orig_node->bcast_bits, seq_diff, 1))
1008                 orig_node->last_bcast_seqno = ntohs(bcast_packet->seqno);
1009
1010         spin_unlock_irqrestore(&orig_hash_lock, flags);
1011         /* rebroadcast packet */
1012         add_bcast_packet_to_list(skb);
1013
1014         /* broadcast for me */
1015         interface_rx(skb, hdr_size);
1016
1017         return NET_RX_SUCCESS;
1018 }
1019
1020 int recv_vis_packet(struct sk_buff *skb)
1021 {
1022         struct vis_packet *vis_packet;
1023         struct ethhdr *ethhdr;
1024         struct bat_priv *bat_priv;
1025         int hdr_size = sizeof(struct vis_packet);
1026
1027         if (skb_headlen(skb) < hdr_size)
1028                 return NET_RX_DROP;
1029
1030         vis_packet = (struct vis_packet *) skb->data;
1031         ethhdr = (struct ethhdr *)skb_mac_header(skb);
1032
1033         /* not for me */
1034         if (!is_my_mac(ethhdr->h_dest))
1035                 return NET_RX_DROP;
1036
1037         /* ignore own packets */
1038         if (is_my_mac(vis_packet->vis_orig))
1039                 return NET_RX_DROP;
1040
1041         if (is_my_mac(vis_packet->sender_orig))
1042                 return NET_RX_DROP;
1043
1044         /* FIXME: each batman_if will be attached to a softif */
1045         bat_priv = netdev_priv(soft_device);
1046
1047         switch (vis_packet->vis_type) {
1048         case VIS_TYPE_SERVER_SYNC:
1049                 /* TODO: handle fragmented skbs properly */
1050                 receive_server_sync_packet(bat_priv, vis_packet,
1051                                            skb_headlen(skb));
1052                 break;
1053
1054         case VIS_TYPE_CLIENT_UPDATE:
1055                 /* TODO: handle fragmented skbs properly */
1056                 receive_client_update_packet(bat_priv, vis_packet,
1057                                              skb_headlen(skb));
1058                 break;
1059
1060         default:        /* ignore unknown packet */
1061                 break;
1062         }
1063
1064         /* We take a copy of the data in the packet, so we should
1065            always free the skbuf. */
1066         return NET_RX_DROP;
1067 }