drivers/staging/batman-adv/routing.c

   1 /*
   2  * Copyright (C) 2007-2009 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, "Changing route towards: %pM (now via %pM - was via %pM)\n", orig_node->orig, neigh_node->addr, orig_node->router->addr);
  98         }
  99
 100         if (neigh_node != NULL)
 101                 orig_node->batman_if = neigh_node->if_incoming;
 102         else
 103                 orig_node->batman_if = NULL;
 104
 105         orig_node->router = neigh_node;
 106 }
 107
 108
 109 void update_routes(struct orig_node *orig_node,
 110                           struct neigh_node *neigh_node,
 111                           unsigned char *hna_buff, int hna_buff_len)
 112 {
 113
 114         if (orig_node == NULL)
 115                 return;
 116
 117         if (orig_node->router != neigh_node)
 118                 update_route(orig_node, neigh_node, hna_buff, hna_buff_len);
 119         /* may be just HNA changed */
 120         else
 121                 update_HNA(orig_node, hna_buff, hna_buff_len);
 122 }
 123
 124 static int isBidirectionalNeigh(struct orig_node *orig_node,
 125                                 struct orig_node *orig_neigh_node,
 126                                 struct batman_packet *batman_packet,
 127                                 struct batman_if *if_incoming)
 128 {
 129         struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 130         unsigned char total_count;
 131
 132         if (orig_node == orig_neigh_node) {
 133                 list_for_each_entry(tmp_neigh_node,
 134                                     &orig_node->neigh_list,
 135                                     list) {
 136
 137                         if (compare_orig(tmp_neigh_node->addr,
 138                                          orig_neigh_node->orig) &&
 139                             (tmp_neigh_node->if_incoming == if_incoming))
 140                                 neigh_node = tmp_neigh_node;
 141                 }
 142
 143                 if (!neigh_node)
 144                         neigh_node = create_neighbor(orig_node,
 145                                                      orig_neigh_node,
 146                                                      orig_neigh_node->orig,
 147                                                      if_incoming);
 148                 /* create_neighbor failed, return 0 */
 149                 if (!neigh_node)
 150                         return 0;
 151
 152                 neigh_node->last_valid = jiffies;
 153         } else {
 154                 /* find packet count of corresponding one hop neighbor */
 155                 list_for_each_entry(tmp_neigh_node,
 156                                     &orig_neigh_node->neigh_list, list) {
 157
 158                         if (compare_orig(tmp_neigh_node->addr,
 159                                          orig_neigh_node->orig) &&
 160                             (tmp_neigh_node->if_incoming == if_incoming))
 161                                 neigh_node = tmp_neigh_node;
 162                 }
 163
 164                 if (!neigh_node)
 165                         neigh_node = create_neighbor(orig_neigh_node,
 166                                                      orig_neigh_node,
 167                                                      orig_neigh_node->orig,
 168                                                      if_incoming);
 169                 /* create_neighbor failed, return 0 */
 170                 if (!neigh_node)
 171                         return 0;
 172         }
 173
 174         orig_node->last_valid = jiffies;
 175
 176         /* pay attention to not get a value bigger than 100 % */
 177         total_count = (orig_neigh_node->bcast_own_sum[if_incoming->if_num] >
 178                        neigh_node->real_packet_count ?
 179                        neigh_node->real_packet_count :
 180                        orig_neigh_node->bcast_own_sum[if_incoming->if_num]);
 181
 182         /* if we have too few packets (too less data) we set tq_own to zero */
 183         /* if we receive too few packets it is not considered bidirectional */
 184         if ((total_count < TQ_LOCAL_BIDRECT_SEND_MINIMUM) ||
 185             (neigh_node->real_packet_count < TQ_LOCAL_BIDRECT_RECV_MINIMUM))
 186                 orig_neigh_node->tq_own = 0;
 187         else
 188                 /* neigh_node->real_packet_count is never zero as we
 189                  * only purge old information when getting new
 190                  * information */
 191                 orig_neigh_node->tq_own = (TQ_MAX_VALUE * total_count) /
 192                         neigh_node->real_packet_count;
 193
 194         /*
 195          * 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
 196          * affect the nearly-symmetric links only a little, but
 197          * punishes asymmetric links more.  This will give a value
 198          * between 0 and TQ_MAX_VALUE
 199          */
 200         orig_neigh_node->tq_asym_penalty =
 201                 TQ_MAX_VALUE -
 202                 (TQ_MAX_VALUE *
 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 - neigh_node->real_packet_count)) /
 206                 (TQ_LOCAL_WINDOW_SIZE *
 207                  TQ_LOCAL_WINDOW_SIZE *
 208                  TQ_LOCAL_WINDOW_SIZE);
 209
 210         batman_packet->tq = ((batman_packet->tq *
 211                               orig_neigh_node->tq_own *
 212                               orig_neigh_node->tq_asym_penalty) /
 213                              (TQ_MAX_VALUE *     TQ_MAX_VALUE));
 214
 215         bat_dbg(DBG_BATMAN, "bidirectional: orig = %-15pM neigh = %-15pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, total tq: %3i \n",
 216                 orig_node->orig, orig_neigh_node->orig, total_count,
 217                 neigh_node->real_packet_count, orig_neigh_node->tq_own,
 218                 orig_neigh_node->tq_asym_penalty, batman_packet->tq);
 219
 220         /* if link has the minimum required transmission quality
 221          * consider it bidirectional */
 222         if (batman_packet->tq >= TQ_TOTAL_BIDRECT_LIMIT)
 223                 return 1;
 224
 225         return 0;
 226 }
 227
 228 static void update_orig(struct orig_node *orig_node, struct ethhdr *ethhdr,
 229                         struct batman_packet *batman_packet,
 230                         struct batman_if *if_incoming,
 231                         unsigned char *hna_buff, int hna_buff_len,
 232                         char is_duplicate)
 233 {
 234         struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 235         int tmp_hna_buff_len;
 236
 237         bat_dbg(DBG_BATMAN, "update_originator(): Searching and updating originator entry of received packet \n");
 238
 239         list_for_each_entry(tmp_neigh_node, &orig_node->neigh_list, list) {
 240                 if (compare_orig(tmp_neigh_node->addr, ethhdr->h_source) &&
 241                     (tmp_neigh_node->if_incoming == if_incoming)) {
 242                         neigh_node = tmp_neigh_node;
 243                         continue;
 244                 }
 245
 246                 if (is_duplicate)
 247                         continue;
 248
 249                 ring_buffer_set(tmp_neigh_node->tq_recv,
 250                                 &tmp_neigh_node->tq_index, 0);
 251                 tmp_neigh_node->tq_avg =
 252                         ring_buffer_avg(tmp_neigh_node->tq_recv);
 253         }
 254
 255         if (!neigh_node) {
 256                 struct orig_node *orig_tmp;
 257
 258                 orig_tmp = get_orig_node(ethhdr->h_source);
 259                 if (!orig_tmp)
 260                         return;
 261
 262                 neigh_node = create_neighbor(orig_node,
 263                                              orig_tmp,
 264                                              ethhdr->h_source, if_incoming);
 265                 if (!neigh_node)
 266                         return;
 267         } else
 268                 bat_dbg(DBG_BATMAN,
 269                         "Updating existing last-hop neighbor of originator\n");
 270
 271         orig_node->flags = batman_packet->flags;
 272         neigh_node->last_valid = jiffies;
 273
 274         ring_buffer_set(neigh_node->tq_recv,
 275                         &neigh_node->tq_index,
 276                         batman_packet->tq);
 277         neigh_node->tq_avg = ring_buffer_avg(neigh_node->tq_recv);
 278
 279         if (!is_duplicate) {
 280                 orig_node->last_ttl = batman_packet->ttl;
 281                 neigh_node->last_ttl = batman_packet->ttl;
 282         }
 283
 284         tmp_hna_buff_len = (hna_buff_len > batman_packet->num_hna * ETH_ALEN ?
 285                             batman_packet->num_hna * ETH_ALEN : hna_buff_len);
 286
 287         /* if this neighbor already is our next hop there is nothing
 288          * to change */
 289         if (orig_node->router == neigh_node)
 290                 goto update_hna;
 291
 292         /* if this neighbor does not offer a better TQ we won't consider it */
 293         if ((orig_node->router) &&
 294             (orig_node->router->tq_avg > neigh_node->tq_avg))
 295                 goto update_hna;
 296
 297         /* if the TQ is the same and the link not more symetric we
 298          * won't consider it either */
 299         if ((orig_node->router) &&
 300              ((neigh_node->tq_avg == orig_node->router->tq_avg) &&
 301              (orig_node->router->orig_node->bcast_own_sum[if_incoming->if_num]
 302               >= neigh_node->orig_node->bcast_own_sum[if_incoming->if_num])))
 303                 goto update_hna;
 304
 305         update_routes(orig_node, neigh_node, hna_buff, tmp_hna_buff_len);
 306         return;
 307
 308 update_hna:
 309         update_routes(orig_node, orig_node->router, hna_buff, tmp_hna_buff_len);
 310 }
 311
 312 static char count_real_packets(struct ethhdr *ethhdr,
 313                                struct batman_packet *batman_packet,
 314                                struct batman_if *if_incoming)
 315 {
 316         struct orig_node *orig_node;
 317         struct neigh_node *tmp_neigh_node;
 318         char is_duplicate = 0;
 319         uint16_t seq_diff;
 320
 321         orig_node = get_orig_node(batman_packet->orig);
 322         if (orig_node == NULL)
 323                 return 0;
 324
 325         list_for_each_entry(tmp_neigh_node, &orig_node->neigh_list, list) {
 326
 327                 if (!is_duplicate)
 328                         is_duplicate =
 329                                 get_bit_status(tmp_neigh_node->real_bits,
 330                                                orig_node->last_real_seqno,
 331                                                batman_packet->seqno);
 332                 seq_diff = batman_packet->seqno - orig_node->last_real_seqno;
 333                 if (compare_orig(tmp_neigh_node->addr, ethhdr->h_source) &&
 334                     (tmp_neigh_node->if_incoming == if_incoming))
 335                         bit_get_packet(tmp_neigh_node->real_bits, seq_diff, 1);
 336                 else
 337                         bit_get_packet(tmp_neigh_node->real_bits, seq_diff, 0);
 338
 339                 tmp_neigh_node->real_packet_count =
 340                         bit_packet_count(tmp_neigh_node->real_bits);
 341         }
 342
 343         if (!is_duplicate) {
 344                 bat_dbg(DBG_BATMAN, "updating last_seqno: old %d, new %d \n",
 345                         orig_node->last_real_seqno, batman_packet->seqno);
 346                 orig_node->last_real_seqno = batman_packet->seqno;
 347         }
 348
 349         return is_duplicate;
 350 }
 351
 352 void receive_bat_packet(struct ethhdr *ethhdr,
 353                                 struct batman_packet *batman_packet,
 354                                 unsigned char *hna_buff, int hna_buff_len,
 355                                 struct batman_if *if_incoming)
 356 {
 357         struct batman_if *batman_if;
 358         struct orig_node *orig_neigh_node, *orig_node;
 359         char has_directlink_flag;
 360         char is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
 361         char is_broadcast = 0, is_bidirectional, is_single_hop_neigh;
 362         char is_duplicate;
 363         unsigned short if_incoming_seqno;
 364
 365         /* Silently drop when the batman packet is actually not a
 366          * correct packet.
 367          *
 368          * This might happen if a packet is padded (e.g. Ethernet has a
 369          * minimum frame length of 64 byte) and the aggregation interprets
 370          * it as an additional length.
 371          *
 372          * TODO: A more sane solution would be to have a bit in the
 373          * batman_packet to detect whether the packet is the last
 374          * packet in an aggregation.  Here we expect that the padding
 375          * is always zero (or not 0x01)
 376          */
 377         if (batman_packet->packet_type != BAT_PACKET)
 378                 return;
 379
 380         /* could be changed by schedule_own_packet() */
 381         if_incoming_seqno = atomic_read(&if_incoming->seqno);
 382
 383         has_directlink_flag = (batman_packet->flags & DIRECTLINK ? 1 : 0);
 384
 385         is_single_hop_neigh = (compare_orig(ethhdr->h_source,
 386                                             batman_packet->orig) ? 1 : 0);
 387
 388         bat_dbg(DBG_BATMAN, "Received BATMAN packet via NB: %pM, IF: %s [%s] (from OG: %pM, via prev OG: %pM, seqno %d, tq %d, TTL %d, V %d, IDF %d) \n",
 389                 ethhdr->h_source, if_incoming->dev, if_incoming->addr_str,
 390                 batman_packet->orig, batman_packet->prev_sender,
 391                 batman_packet->seqno, batman_packet->tq, batman_packet->ttl,
 392                 batman_packet->version, has_directlink_flag);
 393
 394         list_for_each_entry_rcu(batman_if, &if_list, list) {
 395                 if (batman_if->if_active != IF_ACTIVE)
 396                         continue;
 397
 398                 if (compare_orig(ethhdr->h_source,
 399                                  batman_if->net_dev->dev_addr))
 400                         is_my_addr = 1;
 401
 402                 if (compare_orig(batman_packet->orig,
 403                                  batman_if->net_dev->dev_addr))
 404                         is_my_orig = 1;
 405
 406                 if (compare_orig(batman_packet->prev_sender,
 407                                  batman_if->net_dev->dev_addr))
 408                         is_my_oldorig = 1;
 409
 410                 if (compare_orig(ethhdr->h_source, broadcastAddr))
 411                         is_broadcast = 1;
 412         }
 413
 414         if (batman_packet->version != COMPAT_VERSION) {
 415                 bat_dbg(DBG_BATMAN,
 416                         "Drop packet: incompatible batman version (%i)\n",
 417                         batman_packet->version);
 418                 return;
 419         }
 420
 421         if (is_my_addr) {
 422                 bat_dbg(DBG_BATMAN,
 423                         "Drop packet: received my own broadcast (sender: %pM)\n",
 424                         ethhdr->h_source);
 425                 return;
 426         }
 427
 428         if (is_broadcast) {
 429                 bat_dbg(DBG_BATMAN, "Drop packet: ignoring all packets with broadcast source addr (sender: %pM) \n", ethhdr->h_source);
 430                 return;
 431         }
 432
 433         if (is_my_orig) {
 434                 TYPE_OF_WORD *word;
 435                 int offset;
 436
 437                 orig_neigh_node = get_orig_node(ethhdr->h_source);
 438
 439                 if (!orig_neigh_node)
 440                         return;
 441
 442                 /* neighbor has to indicate direct link and it has to
 443                  * come via the corresponding interface */
 444                 /* if received seqno equals last send seqno save new
 445                  * seqno for bidirectional check */
 446                 if (has_directlink_flag &&
 447                     compare_orig(if_incoming->net_dev->dev_addr,
 448                                  batman_packet->orig) &&
 449                     (batman_packet->seqno - if_incoming_seqno + 2 == 0)) {
 450                         offset = if_incoming->if_num * NUM_WORDS;
 451                         word = &(orig_neigh_node->bcast_own[offset]);
 452                         bit_mark(word, 0);
 453                         orig_neigh_node->bcast_own_sum[if_incoming->if_num] =
 454                                 bit_packet_count(word);
 455                 }
 456
 457                 bat_dbg(DBG_BATMAN, "Drop packet: originator packet from myself (via neighbor) \n");
 458                 return;
 459         }
 460
 461         if (batman_packet->tq == 0) {
 462                 count_real_packets(ethhdr, batman_packet, if_incoming);
 463
 464                 bat_dbg(DBG_BATMAN, "Drop packet: originator packet with tq equal 0 \n");
 465                 return;
 466         }
 467
 468         if (is_my_oldorig) {
 469                 bat_dbg(DBG_BATMAN, "Drop packet: ignoring all rebroadcast echos (sender: %pM) \n", ethhdr->h_source);
 470                 return;
 471         }
 472
 473         is_duplicate = count_real_packets(ethhdr, batman_packet, if_incoming);
 474
 475         orig_node = get_orig_node(batman_packet->orig);
 476         if (orig_node == NULL)
 477                 return;
 478
 479         /* avoid temporary routing loops */
 480         if ((orig_node->router) &&
 481             (orig_node->router->orig_node->router) &&
 482             (compare_orig(orig_node->router->addr,
 483                           batman_packet->prev_sender)) &&
 484             !(compare_orig(batman_packet->orig, batman_packet->prev_sender)) &&
 485             (compare_orig(orig_node->router->addr,
 486                           orig_node->router->orig_node->router->addr))) {
 487                 bat_dbg(DBG_BATMAN, "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM) \n", ethhdr->h_source);
 488                 return;
 489         }
 490
 491         /* if sender is a direct neighbor the sender mac equals
 492          * originator mac */
 493         orig_neigh_node = (is_single_hop_neigh ?
 494                            orig_node : get_orig_node(ethhdr->h_source));
 495         if (orig_neigh_node == NULL)
 496                 return;
 497
 498         /* drop packet if sender is not a direct neighbor and if we
 499          * don't route towards it */
 500         if (!is_single_hop_neigh &&
 501             (orig_neigh_node->router == NULL)) {
 502                 bat_dbg(DBG_BATMAN, "Drop packet: OGM via unknown neighbor!\n");
 503                 return;
 504         }
 505
 506         is_bidirectional = isBidirectionalNeigh(orig_node, orig_neigh_node,
 507                                                 batman_packet, if_incoming);
 508
 509         /* update ranking if it is not a duplicate or has the same
 510          * seqno and similar ttl as the non-duplicate */
 511         if (is_bidirectional &&
 512             (!is_duplicate ||
 513              ((orig_node->last_real_seqno == batman_packet->seqno) &&
 514               (orig_node->last_ttl - 3 <= batman_packet->ttl))))
 515                 update_orig(orig_node, ethhdr, batman_packet,
 516                             if_incoming, hna_buff, hna_buff_len, is_duplicate);
 517
 518         /* is single hop (direct) neighbor */
 519         if (is_single_hop_neigh) {
 520
 521                 /* mark direct link on incoming interface */
 522                 schedule_forward_packet(orig_node, ethhdr, batman_packet,
 523                                         1, hna_buff_len, if_incoming);
 524
 525                 bat_dbg(DBG_BATMAN, "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
 526                 return;
 527         }
 528
 529         /* multihop originator */
 530         if (!is_bidirectional) {
 531                 bat_dbg(DBG_BATMAN,
 532                         "Drop packet: not received via bidirectional link\n");
 533                 return;
 534         }
 535
 536         if (is_duplicate) {
 537                 bat_dbg(DBG_BATMAN, "Drop packet: duplicate packet received\n");
 538                 return;
 539         }
 540
 541         bat_dbg(DBG_BATMAN,
 542                 "Forwarding packet: rebroadcast originator packet\n");
 543         schedule_forward_packet(orig_node, ethhdr, batman_packet,
 544                                 0, hna_buff_len, if_incoming);
 545 }
 546
 547 int recv_bat_packet(struct sk_buff *skb,
 548                                 struct batman_if *batman_if)
 549 {
 550         struct ethhdr *ethhdr;
 551         unsigned long flags;
 552
 553         /* drop packet if it has not necessary minimum size */
 554         if (skb_headlen(skb) < sizeof(struct batman_packet))
 555                 return NET_RX_DROP;
 556
 557         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 558
 559         /* packet with broadcast indication but unicast recipient */
 560         if (!is_bcast(ethhdr->h_dest))
 561                 return NET_RX_DROP;
 562
 563         /* packet with broadcast sender address */
 564         if (is_bcast(ethhdr->h_source))
 565                 return NET_RX_DROP;
 566
 567         spin_lock_irqsave(&orig_hash_lock, flags);
 568         /* TODO: we use headlen instead of "length", because
 569          * only this data is paged in. */
 570         /* TODO: is another skb_copy needed here? there will be
 571          * written on the data, but nobody (?) should further use
 572          * this data */
 573         receive_aggr_bat_packet(ethhdr,
 574                                 skb->data,
 575                                 skb_headlen(skb),
 576                                 batman_if);
 577         spin_unlock_irqrestore(&orig_hash_lock, flags);
 578
 579         kfree_skb(skb);
 580         return NET_RX_SUCCESS;
 581 }
 582
 583 static int recv_my_icmp_packet(struct sk_buff *skb)
 584 {
 585         struct orig_node *orig_node;
 586         struct icmp_packet *icmp_packet;
 587         struct ethhdr *ethhdr;
 588         struct sk_buff *skb_old;
 589         struct batman_if *batman_if;
 590         int ret;
 591         unsigned long flags;
 592         uint8_t dstaddr[ETH_ALEN];
 593
 594         icmp_packet = (struct icmp_packet *) skb->data;
 595         ethhdr = (struct ethhdr *) skb_mac_header(skb);
 596
 597         /* add data to device queue */
 598         if (icmp_packet->msg_type != ECHO_REQUEST) {
 599                 bat_device_receive_packet(icmp_packet);
 600                 return NET_RX_DROP;
 601         }
 602
 603         /* answer echo request (ping) */
 604         /* get routing information */
 605         spin_lock_irqsave(&orig_hash_lock, flags);
 606         orig_node = ((struct orig_node *)hash_find(orig_hash,
 607                                                    icmp_packet->orig));
 608         ret = NET_RX_DROP;
 609
 610         if ((orig_node != NULL) &&
 611             (orig_node->batman_if != NULL) &&
 612             (orig_node->router != NULL)) {
 613
 614                 /* don't lock while sending the packets ... we therefore
 615                  * copy the required data before sending */
 616                 batman_if = orig_node->batman_if;
 617                 memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 618                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 619
 620                 /* create a copy of the skb, if needed, to modify it. */
 621                 skb_old = NULL;
 622                 if (!skb_clone_writable(skb, sizeof(struct icmp_packet))) {
 623                         skb_old = skb;
 624                         skb = skb_copy(skb, GFP_ATOMIC);
 625                         if (!skb)
 626                                 return NET_RX_DROP;
 627                         icmp_packet = (struct icmp_packet *) skb->data;
 628                         kfree_skb(skb_old);
 629                 }
 630
 631                 memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
 632                 memcpy(icmp_packet->orig, ethhdr->h_dest, ETH_ALEN);
 633                 icmp_packet->msg_type = ECHO_REPLY;
 634                 icmp_packet->ttl = TTL;
 635
 636                 send_skb_packet(skb, batman_if, dstaddr);
 637                 ret = NET_RX_SUCCESS;
 638
 639         } else
 640                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 641
 642         return ret;
 643 }
 644
 645 static int recv_icmp_ttl_exceeded(struct sk_buff *skb)
 646 {
 647         struct orig_node *orig_node;
 648         struct icmp_packet *icmp_packet;
 649         struct ethhdr *ethhdr;
 650         struct sk_buff *skb_old;
 651         struct batman_if *batman_if;
 652         int ret;
 653         unsigned long flags;
 654         uint8_t dstaddr[ETH_ALEN];
 655
 656         icmp_packet = (struct icmp_packet *)skb->data;
 657         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 658
 659         /* send TTL exceeded if packet is an echo request (traceroute) */
 660         if (icmp_packet->msg_type != ECHO_REQUEST) {
 661                 printk(KERN_WARNING "batman-adv:Warning - can't forward icmp packet from %pM to %pM: ttl exceeded\n",
 662                         icmp_packet->orig, icmp_packet->dst);
 663                 return NET_RX_DROP;
 664         }
 665
 666         /* get routing information */
 667         spin_lock_irqsave(&orig_hash_lock, flags);
 668         orig_node = ((struct orig_node *)
 669                      hash_find(orig_hash, icmp_packet->orig));
 670         ret = NET_RX_DROP;
 671
 672         if ((orig_node != NULL) &&
 673             (orig_node->batman_if != NULL) &&
 674             (orig_node->router != NULL)) {
 675
 676                 /* don't lock while sending the packets ... we therefore
 677                  * copy the required data before sending */
 678                 batman_if = orig_node->batman_if;
 679                 memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 680                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 681
 682                 /* create a copy of the skb, if needed, to modify it. */
 683                 if (!skb_clone_writable(skb, sizeof(struct icmp_packet))) {
 684                         skb_old = skb;
 685                         skb = skb_copy(skb, GFP_ATOMIC);
 686                         if (!skb)
 687                                 return NET_RX_DROP;
 688                         icmp_packet = (struct icmp_packet *) skb->data;
 689                         kfree_skb(skb_old);
 690                 }
 691
 692                 memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
 693                 memcpy(icmp_packet->orig, ethhdr->h_dest, ETH_ALEN);
 694                 icmp_packet->msg_type = TTL_EXCEEDED;
 695                 icmp_packet->ttl = TTL;
 696
 697                 send_skb_packet(skb, batman_if, dstaddr);
 698                 ret = NET_RX_SUCCESS;
 699
 700         } else
 701                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 702
 703         return ret;
 704 }
 705
 706
 707 int recv_icmp_packet(struct sk_buff *skb)
 708 {
 709         struct icmp_packet *icmp_packet;
 710         struct ethhdr *ethhdr;
 711         struct orig_node *orig_node;
 712         struct sk_buff *skb_old;
 713         struct batman_if *batman_if;
 714         int hdr_size = sizeof(struct icmp_packet);
 715         int ret;
 716         unsigned long flags;
 717         uint8_t dstaddr[ETH_ALEN];
 718
 719         /* drop packet if it has not necessary minimum size */
 720         if (skb_headlen(skb) < hdr_size)
 721                 return NET_RX_DROP;
 722
 723         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 724
 725         /* packet with unicast indication but broadcast recipient */
 726         if (is_bcast(ethhdr->h_dest))
 727                 return NET_RX_DROP;
 728
 729         /* packet with broadcast sender address */
 730         if (is_bcast(ethhdr->h_source))
 731                 return NET_RX_DROP;
 732
 733         /* not for me */
 734         if (!is_my_mac(ethhdr->h_dest))
 735                 return NET_RX_DROP;
 736
 737         icmp_packet = (struct icmp_packet *) skb->data;
 738
 739         /* packet for me */
 740         if (is_my_mac(icmp_packet->dst))
 741                 return recv_my_icmp_packet(skb);
 742
 743         /* TTL exceeded */
 744         if (icmp_packet->ttl < 2)
 745                 return recv_icmp_ttl_exceeded(skb);
 746
 747         ret = NET_RX_DROP;
 748
 749         /* get routing information */
 750         spin_lock_irqsave(&orig_hash_lock, flags);
 751         orig_node = ((struct orig_node *)
 752                      hash_find(orig_hash, icmp_packet->dst));
 753
 754         if ((orig_node != NULL) &&
 755             (orig_node->batman_if != NULL) &&
 756             (orig_node->router != NULL)) {
 757
 758                 /* don't lock while sending the packets ... we therefore
 759                  * copy the required data before sending */
 760                 batman_if = orig_node->batman_if;
 761                 memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 762                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 763
 764                 /* create a copy of the skb, if needed, to modify it. */
 765                 if (!skb_clone_writable(skb, sizeof(struct icmp_packet))) {
 766                         skb_old = skb;
 767                         skb = skb_copy(skb, GFP_ATOMIC);
 768                         if (!skb)
 769                                 return NET_RX_DROP;
 770                         icmp_packet = (struct icmp_packet *) skb->data;
 771                         kfree_skb(skb_old);
 772                 }
 773
 774                 /* decrement ttl */
 775                 icmp_packet->ttl--;
 776
 777                 /* route it */
 778                 send_skb_packet(skb, batman_if, dstaddr);
 779                 ret = NET_RX_SUCCESS;
 780
 781         } else
 782                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 783
 784         return ret;
 785 }
 786
 787 int recv_unicast_packet(struct sk_buff *skb)
 788 {
 789         struct unicast_packet *unicast_packet;
 790         struct orig_node *orig_node;
 791         struct ethhdr *ethhdr;
 792         struct batman_if *batman_if;
 793         struct sk_buff *skb_old;
 794         uint8_t dstaddr[ETH_ALEN];
 795         int hdr_size = sizeof(struct unicast_packet);
 796         int ret;
 797         unsigned long flags;
 798
 799         /* drop packet if it has not necessary minimum size */
 800         if (skb_headlen(skb) < hdr_size)
 801                 return NET_RX_DROP;
 802
 803         ethhdr = (struct ethhdr *) skb_mac_header(skb);
 804
 805         /* packet with unicast indication but broadcast recipient */
 806         if (is_bcast(ethhdr->h_dest))
 807                 return NET_RX_DROP;
 808
 809         /* packet with broadcast sender address */
 810         if (is_bcast(ethhdr->h_source))
 811                 return NET_RX_DROP;
 812
 813         /* not for me */
 814         if (!is_my_mac(ethhdr->h_dest))
 815                 return NET_RX_DROP;
 816
 817         unicast_packet = (struct unicast_packet *) skb->data;
 818
 819         /* packet for me */
 820         if (is_my_mac(unicast_packet->dest)) {
 821                 interface_rx(skb, hdr_size);
 822                 return NET_RX_SUCCESS;
 823         }
 824
 825         /* TTL exceeded */
 826         if (unicast_packet->ttl < 2) {
 827                 printk(KERN_WARNING "batman-adv:Warning - can't forward unicast packet from %pM to %pM: ttl exceeded\n",
 828                        ethhdr->h_source, unicast_packet->dest);
 829                 return NET_RX_DROP;
 830         }
 831
 832         ret = NET_RX_DROP;
 833         /* get routing information */
 834         spin_lock_irqsave(&orig_hash_lock, flags);
 835         orig_node = ((struct orig_node *)
 836                      hash_find(orig_hash, unicast_packet->dest));
 837
 838         if ((orig_node != NULL) &&
 839             (orig_node->batman_if != NULL) &&
 840             (orig_node->router != NULL)) {
 841
 842                 /* don't lock while sending the packets ... we therefore
 843                  * copy the required data before sending */
 844                 batman_if = orig_node->batman_if;
 845                 memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 846                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 847
 848                 /* create a copy of the skb, if needed, to modify it. */
 849                 if (!skb_clone_writable(skb, sizeof(struct unicast_packet))) {
 850                         skb_old = skb;
 851                         skb = skb_copy(skb, GFP_ATOMIC);
 852                         if (!skb)
 853                                 return NET_RX_DROP;
 854                         unicast_packet = (struct unicast_packet *) skb->data;
 855                         kfree_skb(skb_old);
 856                 }
 857                 /* decrement ttl */
 858                 unicast_packet->ttl--;
 859
 860                 /* route it */
 861                 send_skb_packet(skb, batman_if, dstaddr);
 862                 ret = NET_RX_SUCCESS;
 863
 864         } else
 865                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 866
 867         return ret;
 868 }
 869
 870
 871 int recv_bcast_packet(struct sk_buff *skb)
 872 {
 873         struct orig_node *orig_node;
 874         struct bcast_packet *bcast_packet;
 875         struct ethhdr *ethhdr;
 876         int hdr_size = sizeof(struct bcast_packet);
 877         unsigned long flags;
 878
 879         /* drop packet if it has not necessary minimum size */
 880         if (skb_headlen(skb) < hdr_size)
 881                 return NET_RX_DROP;
 882
 883         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 884
 885         /* packet with broadcast indication but unicast recipient */
 886         if (!is_bcast(ethhdr->h_dest))
 887                 return NET_RX_DROP;
 888
 889         /* packet with broadcast sender address */
 890         if (is_bcast(ethhdr->h_source))
 891                 return NET_RX_DROP;
 892
 893         /* ignore broadcasts sent by myself */
 894         if (is_my_mac(ethhdr->h_source))
 895                 return NET_RX_DROP;
 896
 897         bcast_packet = (struct bcast_packet *) skb->data;
 898
 899         /* ignore broadcasts originated by myself */
 900         if (is_my_mac(bcast_packet->orig))
 901                 return NET_RX_DROP;
 902
 903         spin_lock_irqsave(&orig_hash_lock, flags);
 904         orig_node = ((struct orig_node *)
 905                      hash_find(orig_hash, bcast_packet->orig));
 906
 907         if (orig_node == NULL) {
 908                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 909                 return NET_RX_DROP;
 910         }
 911
 912         /* check flood history */
 913         if (get_bit_status(orig_node->bcast_bits,
 914                            orig_node->last_bcast_seqno,
 915                            ntohs(bcast_packet->seqno))) {
 916                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 917                 return NET_RX_DROP;
 918         }
 919
 920         /* mark broadcast in flood history */
 921         if (bit_get_packet(orig_node->bcast_bits,
 922                            ntohs(bcast_packet->seqno) -
 923                            orig_node->last_bcast_seqno, 1))
 924                 orig_node->last_bcast_seqno = ntohs(bcast_packet->seqno);
 925
 926         spin_unlock_irqrestore(&orig_hash_lock, flags);
 927
 928         /* rebroadcast packet */
 929         add_bcast_packet_to_list(skb);
 930
 931         /* broadcast for me */
 932         interface_rx(skb, hdr_size);
 933
 934         return NET_RX_SUCCESS;
 935 }
 936
 937 int recv_vis_packet(struct sk_buff *skb)
 938 {
 939         struct vis_packet *vis_packet;
 940         struct ethhdr *ethhdr;
 941         int hdr_size = sizeof(struct vis_packet);
 942
 943         if (skb_headlen(skb) < hdr_size)
 944                 return NET_RX_DROP;
 945
 946         vis_packet = (struct vis_packet *) skb->data;
 947         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 948
 949         /* not for me */
 950         if (!is_my_mac(ethhdr->h_dest))
 951                 return NET_RX_DROP;
 952
 953         /* ignore own packets */
 954         if (is_my_mac(vis_packet->vis_orig))
 955                 return NET_RX_DROP;
 956
 957         if (is_my_mac(vis_packet->sender_orig))
 958                 return NET_RX_DROP;
 959
 960         switch (vis_packet->vis_type) {
 961         case VIS_TYPE_SERVER_SYNC:
 962                 /* TODO: handle fragmented skbs properly */
 963                 receive_server_sync_packet(vis_packet, skb_headlen(skb));
 964                 break;
 965
 966         case VIS_TYPE_CLIENT_UPDATE:
 967                 /* TODO: handle fragmented skbs properly */
 968                 receive_client_update_packet(vis_packet, skb_headlen(skb));
 969                 break;
 970
 971         default:        /* ignore unknown packet */
 972                 break;
 973         }
 974
 975         /* We take a copy of the data in the packet, so we should
 976            always free the skbuf. */
 977         return NET_RX_DROP;
 978 }