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, "Changing route towards: %pM (now via %pM - was via %pM)\n", orig_node->orig, neigh_node->addr, orig_node->router->addr);
  98         }
  99
 100         orig_node->router = neigh_node;
 101 }
 102
 103
 104 void update_routes(struct orig_node *orig_node,
 105                           struct neigh_node *neigh_node,
 106                           unsigned char *hna_buff, int hna_buff_len)
 107 {
 108
 109         if (orig_node == NULL)
 110                 return;
 111
 112         if (orig_node->router != neigh_node)
 113                 update_route(orig_node, neigh_node, hna_buff, hna_buff_len);
 114         /* may be just HNA changed */
 115         else
 116                 update_HNA(orig_node, hna_buff, hna_buff_len);
 117 }
 118
 119 static int isBidirectionalNeigh(struct orig_node *orig_node,
 120                                 struct orig_node *orig_neigh_node,
 121                                 struct batman_packet *batman_packet,
 122                                 struct batman_if *if_incoming)
 123 {
 124         struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 125         unsigned char total_count;
 126
 127         if (orig_node == orig_neigh_node) {
 128                 list_for_each_entry(tmp_neigh_node,
 129                                     &orig_node->neigh_list,
 130                                     list) {
 131
 132                         if (compare_orig(tmp_neigh_node->addr,
 133                                          orig_neigh_node->orig) &&
 134                             (tmp_neigh_node->if_incoming == if_incoming))
 135                                 neigh_node = tmp_neigh_node;
 136                 }
 137
 138                 if (!neigh_node)
 139                         neigh_node = create_neighbor(orig_node,
 140                                                      orig_neigh_node,
 141                                                      orig_neigh_node->orig,
 142                                                      if_incoming);
 143                 /* create_neighbor failed, return 0 */
 144                 if (!neigh_node)
 145                         return 0;
 146
 147                 neigh_node->last_valid = jiffies;
 148         } else {
 149                 /* find packet count of corresponding one hop neighbor */
 150                 list_for_each_entry(tmp_neigh_node,
 151                                     &orig_neigh_node->neigh_list, list) {
 152
 153                         if (compare_orig(tmp_neigh_node->addr,
 154                                          orig_neigh_node->orig) &&
 155                             (tmp_neigh_node->if_incoming == if_incoming))
 156                                 neigh_node = tmp_neigh_node;
 157                 }
 158
 159                 if (!neigh_node)
 160                         neigh_node = create_neighbor(orig_neigh_node,
 161                                                      orig_neigh_node,
 162                                                      orig_neigh_node->orig,
 163                                                      if_incoming);
 164                 /* create_neighbor failed, return 0 */
 165                 if (!neigh_node)
 166                         return 0;
 167         }
 168
 169         orig_node->last_valid = jiffies;
 170
 171         /* pay attention to not get a value bigger than 100 % */
 172         total_count = (orig_neigh_node->bcast_own_sum[if_incoming->if_num] >
 173                        neigh_node->real_packet_count ?
 174                        neigh_node->real_packet_count :
 175                        orig_neigh_node->bcast_own_sum[if_incoming->if_num]);
 176
 177         /* if we have too few packets (too less data) we set tq_own to zero */
 178         /* if we receive too few packets it is not considered bidirectional */
 179         if ((total_count < TQ_LOCAL_BIDRECT_SEND_MINIMUM) ||
 180             (neigh_node->real_packet_count < TQ_LOCAL_BIDRECT_RECV_MINIMUM))
 181                 orig_neigh_node->tq_own = 0;
 182         else
 183                 /* neigh_node->real_packet_count is never zero as we
 184                  * only purge old information when getting new
 185                  * information */
 186                 orig_neigh_node->tq_own = (TQ_MAX_VALUE * total_count) /
 187                         neigh_node->real_packet_count;
 188
 189         /*
 190          * 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
 191          * affect the nearly-symmetric links only a little, but
 192          * punishes asymmetric links more.  This will give a value
 193          * between 0 and TQ_MAX_VALUE
 194          */
 195         orig_neigh_node->tq_asym_penalty =
 196                 TQ_MAX_VALUE -
 197                 (TQ_MAX_VALUE *
 198                  (TQ_LOCAL_WINDOW_SIZE - neigh_node->real_packet_count) *
 199                  (TQ_LOCAL_WINDOW_SIZE - neigh_node->real_packet_count) *
 200                  (TQ_LOCAL_WINDOW_SIZE - neigh_node->real_packet_count)) /
 201                 (TQ_LOCAL_WINDOW_SIZE *
 202                  TQ_LOCAL_WINDOW_SIZE *
 203                  TQ_LOCAL_WINDOW_SIZE);
 204
 205         batman_packet->tq = ((batman_packet->tq *
 206                               orig_neigh_node->tq_own *
 207                               orig_neigh_node->tq_asym_penalty) /
 208                              (TQ_MAX_VALUE * TQ_MAX_VALUE));
 209
 210         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",
 211                 orig_node->orig, orig_neigh_node->orig, total_count,
 212                 neigh_node->real_packet_count, orig_neigh_node->tq_own,
 213                 orig_neigh_node->tq_asym_penalty, batman_packet->tq);
 214
 215         /* if link has the minimum required transmission quality
 216          * consider it bidirectional */
 217         if (batman_packet->tq >= TQ_TOTAL_BIDRECT_LIMIT)
 218                 return 1;
 219
 220         return 0;
 221 }
 222
 223 static void update_orig(struct orig_node *orig_node, struct ethhdr *ethhdr,
 224                         struct batman_packet *batman_packet,
 225                         struct batman_if *if_incoming,
 226                         unsigned char *hna_buff, int hna_buff_len,
 227                         char is_duplicate)
 228 {
 229         struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
 230         int tmp_hna_buff_len;
 231
 232         bat_dbg(DBG_BATMAN, "update_originator(): Searching and updating originator entry of received packet\n");
 233
 234         list_for_each_entry(tmp_neigh_node, &orig_node->neigh_list, list) {
 235                 if (compare_orig(tmp_neigh_node->addr, ethhdr->h_source) &&
 236                     (tmp_neigh_node->if_incoming == if_incoming)) {
 237                         neigh_node = tmp_neigh_node;
 238                         continue;
 239                 }
 240
 241                 if (is_duplicate)
 242                         continue;
 243
 244                 ring_buffer_set(tmp_neigh_node->tq_recv,
 245                                 &tmp_neigh_node->tq_index, 0);
 246                 tmp_neigh_node->tq_avg =
 247                         ring_buffer_avg(tmp_neigh_node->tq_recv);
 248         }
 249
 250         if (!neigh_node) {
 251                 struct orig_node *orig_tmp;
 252
 253                 orig_tmp = get_orig_node(ethhdr->h_source);
 254                 if (!orig_tmp)
 255                         return;
 256
 257                 neigh_node = create_neighbor(orig_node,
 258                                              orig_tmp,
 259                                              ethhdr->h_source, if_incoming);
 260                 if (!neigh_node)
 261                         return;
 262         } else
 263                 bat_dbg(DBG_BATMAN,
 264                         "Updating existing last-hop neighbor of originator\n");
 265
 266         orig_node->flags = batman_packet->flags;
 267         neigh_node->last_valid = jiffies;
 268
 269         ring_buffer_set(neigh_node->tq_recv,
 270                         &neigh_node->tq_index,
 271                         batman_packet->tq);
 272         neigh_node->tq_avg = ring_buffer_avg(neigh_node->tq_recv);
 273
 274         if (!is_duplicate) {
 275                 orig_node->last_ttl = batman_packet->ttl;
 276                 neigh_node->last_ttl = batman_packet->ttl;
 277         }
 278
 279         tmp_hna_buff_len = (hna_buff_len > batman_packet->num_hna * ETH_ALEN ?
 280                             batman_packet->num_hna * ETH_ALEN : hna_buff_len);
 281
 282         /* if this neighbor already is our next hop there is nothing
 283          * to change */
 284         if (orig_node->router == neigh_node)
 285                 goto update_hna;
 286
 287         /* if this neighbor does not offer a better TQ we won't consider it */
 288         if ((orig_node->router) &&
 289             (orig_node->router->tq_avg > neigh_node->tq_avg))
 290                 goto update_hna;
 291
 292         /* if the TQ is the same and the link not more symetric we
 293          * won't consider it either */
 294         if ((orig_node->router) &&
 295              ((neigh_node->tq_avg == orig_node->router->tq_avg) &&
 296              (orig_node->router->orig_node->bcast_own_sum[if_incoming->if_num]
 297               >= neigh_node->orig_node->bcast_own_sum[if_incoming->if_num])))
 298                 goto update_hna;
 299
 300         update_routes(orig_node, neigh_node, hna_buff, tmp_hna_buff_len);
 301         return;
 302
 303 update_hna:
 304         update_routes(orig_node, orig_node->router, hna_buff, tmp_hna_buff_len);
 305 }
 306
 307 static char count_real_packets(struct ethhdr *ethhdr,
 308                                struct batman_packet *batman_packet,
 309                                struct batman_if *if_incoming)
 310 {
 311         struct orig_node *orig_node;
 312         struct neigh_node *tmp_neigh_node;
 313         char is_duplicate = 0;
 314         uint16_t seq_diff;
 315
 316         orig_node = get_orig_node(batman_packet->orig);
 317         if (orig_node == NULL)
 318                 return 0;
 319
 320         list_for_each_entry(tmp_neigh_node, &orig_node->neigh_list, list) {
 321
 322                 if (!is_duplicate)
 323                         is_duplicate =
 324                                 get_bit_status(tmp_neigh_node->real_bits,
 325                                                orig_node->last_real_seqno,
 326                                                batman_packet->seqno);
 327                 seq_diff = batman_packet->seqno - orig_node->last_real_seqno;
 328                 if (compare_orig(tmp_neigh_node->addr, ethhdr->h_source) &&
 329                     (tmp_neigh_node->if_incoming == if_incoming))
 330                         bit_get_packet(tmp_neigh_node->real_bits, seq_diff, 1);
 331                 else
 332                         bit_get_packet(tmp_neigh_node->real_bits, seq_diff, 0);
 333
 334                 tmp_neigh_node->real_packet_count =
 335                         bit_packet_count(tmp_neigh_node->real_bits);
 336         }
 337
 338         if (!is_duplicate) {
 339                 bat_dbg(DBG_BATMAN, "updating last_seqno: old %d, new %d\n",
 340                         orig_node->last_real_seqno, batman_packet->seqno);
 341                 orig_node->last_real_seqno = batman_packet->seqno;
 342         }
 343
 344         return is_duplicate;
 345 }
 346
 347 void receive_bat_packet(struct ethhdr *ethhdr,
 348                                 struct batman_packet *batman_packet,
 349                                 unsigned char *hna_buff, int hna_buff_len,
 350                                 struct batman_if *if_incoming)
 351 {
 352         struct batman_if *batman_if;
 353         struct orig_node *orig_neigh_node, *orig_node;
 354         char has_directlink_flag;
 355         char is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
 356         char is_broadcast = 0, is_bidirectional, is_single_hop_neigh;
 357         char is_duplicate;
 358         unsigned short if_incoming_seqno;
 359
 360         /* Silently drop when the batman packet is actually not a
 361          * correct packet.
 362          *
 363          * This might happen if a packet is padded (e.g. Ethernet has a
 364          * minimum frame length of 64 byte) and the aggregation interprets
 365          * it as an additional length.
 366          *
 367          * TODO: A more sane solution would be to have a bit in the
 368          * batman_packet to detect whether the packet is the last
 369          * packet in an aggregation.  Here we expect that the padding
 370          * is always zero (or not 0x01)
 371          */
 372         if (batman_packet->packet_type != BAT_PACKET)
 373                 return;
 374
 375         /* could be changed by schedule_own_packet() */
 376         if_incoming_seqno = atomic_read(&if_incoming->seqno);
 377
 378         has_directlink_flag = (batman_packet->flags & DIRECTLINK ? 1 : 0);
 379
 380         is_single_hop_neigh = (compare_orig(ethhdr->h_source,
 381                                             batman_packet->orig) ? 1 : 0);
 382
 383         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",
 384                 ethhdr->h_source, if_incoming->dev, if_incoming->addr_str,
 385                 batman_packet->orig, batman_packet->prev_sender,
 386                 batman_packet->seqno, batman_packet->tq, batman_packet->ttl,
 387                 batman_packet->version, has_directlink_flag);
 388
 389         list_for_each_entry_rcu(batman_if, &if_list, list) {
 390                 if (batman_if->if_status != IF_ACTIVE)
 391                         continue;
 392
 393                 if (compare_orig(ethhdr->h_source,
 394                                  batman_if->net_dev->dev_addr))
 395                         is_my_addr = 1;
 396
 397                 if (compare_orig(batman_packet->orig,
 398                                  batman_if->net_dev->dev_addr))
 399                         is_my_orig = 1;
 400
 401                 if (compare_orig(batman_packet->prev_sender,
 402                                  batman_if->net_dev->dev_addr))
 403                         is_my_oldorig = 1;
 404
 405                 if (compare_orig(ethhdr->h_source, broadcastAddr))
 406                         is_broadcast = 1;
 407         }
 408
 409         if (batman_packet->version != COMPAT_VERSION) {
 410                 bat_dbg(DBG_BATMAN,
 411                         "Drop packet: incompatible batman version (%i)\n",
 412                         batman_packet->version);
 413                 return;
 414         }
 415
 416         if (is_my_addr) {
 417                 bat_dbg(DBG_BATMAN,
 418                         "Drop packet: received my own broadcast (sender: %pM)\n",
 419                         ethhdr->h_source);
 420                 return;
 421         }
 422
 423         if (is_broadcast) {
 424                 bat_dbg(DBG_BATMAN, "Drop packet: ignoring all packets with broadcast source addr (sender: %pM)\n", ethhdr->h_source);
 425                 return;
 426         }
 427
 428         if (is_my_orig) {
 429                 TYPE_OF_WORD *word;
 430                 int offset;
 431
 432                 orig_neigh_node = get_orig_node(ethhdr->h_source);
 433
 434                 if (!orig_neigh_node)
 435                         return;
 436
 437                 /* neighbor has to indicate direct link and it has to
 438                  * come via the corresponding interface */
 439                 /* if received seqno equals last send seqno save new
 440                  * seqno for bidirectional check */
 441                 if (has_directlink_flag &&
 442                     compare_orig(if_incoming->net_dev->dev_addr,
 443                                  batman_packet->orig) &&
 444                     (batman_packet->seqno - if_incoming_seqno + 2 == 0)) {
 445                         offset = if_incoming->if_num * NUM_WORDS;
 446                         word = &(orig_neigh_node->bcast_own[offset]);
 447                         bit_mark(word, 0);
 448                         orig_neigh_node->bcast_own_sum[if_incoming->if_num] =
 449                                 bit_packet_count(word);
 450                 }
 451
 452                 bat_dbg(DBG_BATMAN, "Drop packet: originator packet from myself (via neighbor)\n");
 453                 return;
 454         }
 455
 456         if (batman_packet->tq == 0) {
 457                 count_real_packets(ethhdr, batman_packet, if_incoming);
 458
 459                 bat_dbg(DBG_BATMAN, "Drop packet: originator packet with tq equal 0\n");
 460                 return;
 461         }
 462
 463         if (is_my_oldorig) {
 464                 bat_dbg(DBG_BATMAN, "Drop packet: ignoring all rebroadcast echos (sender: %pM)\n", ethhdr->h_source);
 465                 return;
 466         }
 467
 468         is_duplicate = count_real_packets(ethhdr, batman_packet, if_incoming);
 469
 470         orig_node = get_orig_node(batman_packet->orig);
 471         if (orig_node == NULL)
 472                 return;
 473
 474         /* avoid temporary routing loops */
 475         if ((orig_node->router) &&
 476             (orig_node->router->orig_node->router) &&
 477             (compare_orig(orig_node->router->addr,
 478                           batman_packet->prev_sender)) &&
 479             !(compare_orig(batman_packet->orig, batman_packet->prev_sender)) &&
 480             (compare_orig(orig_node->router->addr,
 481                           orig_node->router->orig_node->router->addr))) {
 482                 bat_dbg(DBG_BATMAN, "Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n", ethhdr->h_source);
 483                 return;
 484         }
 485
 486         /* if sender is a direct neighbor the sender mac equals
 487          * originator mac */
 488         orig_neigh_node = (is_single_hop_neigh ?
 489                            orig_node : get_orig_node(ethhdr->h_source));
 490         if (orig_neigh_node == NULL)
 491                 return;
 492
 493         /* drop packet if sender is not a direct neighbor and if we
 494          * don't route towards it */
 495         if (!is_single_hop_neigh &&
 496             (orig_neigh_node->router == NULL)) {
 497                 bat_dbg(DBG_BATMAN, "Drop packet: OGM via unknown neighbor!\n");
 498                 return;
 499         }
 500
 501         is_bidirectional = isBidirectionalNeigh(orig_node, orig_neigh_node,
 502                                                 batman_packet, if_incoming);
 503
 504         /* update ranking if it is not a duplicate or has the same
 505          * seqno and similar ttl as the non-duplicate */
 506         if (is_bidirectional &&
 507             (!is_duplicate ||
 508              ((orig_node->last_real_seqno == batman_packet->seqno) &&
 509               (orig_node->last_ttl - 3 <= batman_packet->ttl))))
 510                 update_orig(orig_node, ethhdr, batman_packet,
 511                             if_incoming, hna_buff, hna_buff_len, is_duplicate);
 512
 513         /* is single hop (direct) neighbor */
 514         if (is_single_hop_neigh) {
 515
 516                 /* mark direct link on incoming interface */
 517                 schedule_forward_packet(orig_node, ethhdr, batman_packet,
 518                                         1, hna_buff_len, if_incoming);
 519
 520                 bat_dbg(DBG_BATMAN, "Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
 521                 return;
 522         }
 523
 524         /* multihop originator */
 525         if (!is_bidirectional) {
 526                 bat_dbg(DBG_BATMAN,
 527                         "Drop packet: not received via bidirectional link\n");
 528                 return;
 529         }
 530
 531         if (is_duplicate) {
 532                 bat_dbg(DBG_BATMAN, "Drop packet: duplicate packet received\n");
 533                 return;
 534         }
 535
 536         bat_dbg(DBG_BATMAN,
 537                 "Forwarding packet: rebroadcast originator packet\n");
 538         schedule_forward_packet(orig_node, ethhdr, batman_packet,
 539                                 0, hna_buff_len, if_incoming);
 540 }
 541
 542 int recv_bat_packet(struct sk_buff *skb,
 543                                 struct batman_if *batman_if)
 544 {
 545         struct ethhdr *ethhdr;
 546         unsigned long flags;
 547         struct sk_buff *skb_old;
 548
 549         /* drop packet if it has not necessary minimum size */
 550         if (skb_headlen(skb) < sizeof(struct batman_packet))
 551                 return NET_RX_DROP;
 552
 553         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 554
 555         /* packet with broadcast indication but unicast recipient */
 556         if (!is_bcast(ethhdr->h_dest))
 557                 return NET_RX_DROP;
 558
 559         /* packet with broadcast sender address */
 560         if (is_bcast(ethhdr->h_source))
 561                 return NET_RX_DROP;
 562
 563         /* TODO: we use headlen instead of "length", because
 564          * only this data is paged in. */
 565
 566         /* create a copy of the skb, if needed, to modify it. */
 567         if (!skb_clone_writable(skb, skb_headlen(skb))) {
 568                 skb_old = skb;
 569                 skb = skb_copy(skb, GFP_ATOMIC);
 570                 if (!skb)
 571                         return NET_RX_DROP;
 572                 kfree_skb(skb_old);
 573         }
 574
 575         spin_lock_irqsave(&orig_hash_lock, flags);
 576         receive_aggr_bat_packet(ethhdr,
 577                                 skb->data,
 578                                 skb_headlen(skb),
 579                                 batman_if);
 580         spin_unlock_irqrestore(&orig_hash_lock, flags);
 581
 582         kfree_skb(skb);
 583         return NET_RX_SUCCESS;
 584 }
 585
 586 static int recv_my_icmp_packet(struct sk_buff *skb)
 587 {
 588         struct orig_node *orig_node;
 589         struct icmp_packet *icmp_packet;
 590         struct ethhdr *ethhdr;
 591         struct sk_buff *skb_old;
 592         struct batman_if *batman_if;
 593         int ret;
 594         unsigned long flags;
 595         uint8_t dstaddr[ETH_ALEN];
 596
 597         icmp_packet = (struct icmp_packet *) skb->data;
 598         ethhdr = (struct ethhdr *) skb_mac_header(skb);
 599
 600         /* add data to device queue */
 601         if (icmp_packet->msg_type != ECHO_REQUEST) {
 602                 bat_device_receive_packet(icmp_packet);
 603                 return NET_RX_DROP;
 604         }
 605
 606         /* answer echo request (ping) */
 607         /* get routing information */
 608         spin_lock_irqsave(&orig_hash_lock, flags);
 609         orig_node = ((struct orig_node *)hash_find(orig_hash,
 610                                                    icmp_packet->orig));
 611         ret = NET_RX_DROP;
 612
 613         if ((orig_node != NULL) &&
 614             (orig_node->router != NULL)) {
 615
 616                 /* don't lock while sending the packets ... we therefore
 617                  * copy the required data before sending */
 618                 batman_if = orig_node->router->if_incoming;
 619                 memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 620                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 621
 622                 /* create a copy of the skb, if needed, to modify it. */
 623                 skb_old = NULL;
 624                 if (!skb_clone_writable(skb, sizeof(struct icmp_packet))) {
 625                         skb_old = skb;
 626                         skb = skb_copy(skb, GFP_ATOMIC);
 627                         if (!skb)
 628                                 return NET_RX_DROP;
 629                         icmp_packet = (struct icmp_packet *) skb->data;
 630                         kfree_skb(skb_old);
 631                 }
 632
 633                 memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
 634                 memcpy(icmp_packet->orig, ethhdr->h_dest, ETH_ALEN);
 635                 icmp_packet->msg_type = ECHO_REPLY;
 636                 icmp_packet->ttl = TTL;
 637
 638                 send_skb_packet(skb, batman_if, dstaddr);
 639                 ret = NET_RX_SUCCESS;
 640
 641         } else
 642                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 643
 644         return ret;
 645 }
 646
 647 static int recv_icmp_ttl_exceeded(struct sk_buff *skb)
 648 {
 649         struct orig_node *orig_node;
 650         struct icmp_packet *icmp_packet;
 651         struct ethhdr *ethhdr;
 652         struct sk_buff *skb_old;
 653         struct batman_if *batman_if;
 654         int ret;
 655         unsigned long flags;
 656         uint8_t dstaddr[ETH_ALEN];
 657
 658         icmp_packet = (struct icmp_packet *)skb->data;
 659         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 660
 661         /* send TTL exceeded if packet is an echo request (traceroute) */
 662         if (icmp_packet->msg_type != ECHO_REQUEST) {
 663                 printk(KERN_WARNING "batman-adv:Warning - can't forward icmp packet from %pM to %pM: ttl exceeded\n",
 664                         icmp_packet->orig, icmp_packet->dst);
 665                 return NET_RX_DROP;
 666         }
 667
 668         /* get routing information */
 669         spin_lock_irqsave(&orig_hash_lock, flags);
 670         orig_node = ((struct orig_node *)
 671                      hash_find(orig_hash, icmp_packet->orig));
 672         ret = NET_RX_DROP;
 673
 674         if ((orig_node != NULL) &&
 675             (orig_node->router != NULL)) {
 676
 677                 /* don't lock while sending the packets ... we therefore
 678                  * copy the required data before sending */
 679                 batman_if = orig_node->router->if_incoming;
 680                 memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 681                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 682
 683                 /* create a copy of the skb, if needed, to modify it. */
 684                 if (!skb_clone_writable(skb, sizeof(struct icmp_packet))) {
 685                         skb_old = skb;
 686                         skb = skb_copy(skb, GFP_ATOMIC);
 687                         if (!skb)
 688                                 return NET_RX_DROP;
 689                         icmp_packet = (struct icmp_packet *) skb->data;
 690                         kfree_skb(skb_old);
 691                 }
 692
 693                 memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
 694                 memcpy(icmp_packet->orig, ethhdr->h_dest, ETH_ALEN);
 695                 icmp_packet->msg_type = TTL_EXCEEDED;
 696                 icmp_packet->ttl = TTL;
 697
 698                 send_skb_packet(skb, batman_if, dstaddr);
 699                 ret = NET_RX_SUCCESS;
 700
 701         } else
 702                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 703
 704         return ret;
 705 }
 706
 707
 708 int recv_icmp_packet(struct sk_buff *skb)
 709 {
 710         struct icmp_packet *icmp_packet;
 711         struct ethhdr *ethhdr;
 712         struct orig_node *orig_node;
 713         struct sk_buff *skb_old;
 714         struct batman_if *batman_if;
 715         int hdr_size = sizeof(struct icmp_packet);
 716         int ret;
 717         unsigned long flags;
 718         uint8_t dstaddr[ETH_ALEN];
 719
 720         /* drop packet if it has not necessary minimum size */
 721         if (skb_headlen(skb) < hdr_size)
 722                 return NET_RX_DROP;
 723
 724         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 725
 726         /* packet with unicast indication but broadcast recipient */
 727         if (is_bcast(ethhdr->h_dest))
 728                 return NET_RX_DROP;
 729
 730         /* packet with broadcast sender address */
 731         if (is_bcast(ethhdr->h_source))
 732                 return NET_RX_DROP;
 733
 734         /* not for me */
 735         if (!is_my_mac(ethhdr->h_dest))
 736                 return NET_RX_DROP;
 737
 738         icmp_packet = (struct icmp_packet *) skb->data;
 739
 740         /* packet for me */
 741         if (is_my_mac(icmp_packet->dst))
 742                 return recv_my_icmp_packet(skb);
 743
 744         /* TTL exceeded */
 745         if (icmp_packet->ttl < 2)
 746                 return recv_icmp_ttl_exceeded(skb);
 747
 748         ret = NET_RX_DROP;
 749
 750         /* get routing information */
 751         spin_lock_irqsave(&orig_hash_lock, flags);
 752         orig_node = ((struct orig_node *)
 753                      hash_find(orig_hash, icmp_packet->dst));
 754
 755         if ((orig_node != 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->router->if_incoming;
 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->router != NULL)) {
 840
 841                 /* don't lock while sending the packets ... we therefore
 842                  * copy the required data before sending */
 843                 batman_if = orig_node->router->if_incoming;
 844                 memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
 845                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 846
 847                 /* create a copy of the skb, if needed, to modify it. */
 848                 if (!skb_clone_writable(skb, sizeof(struct unicast_packet))) {
 849                         skb_old = skb;
 850                         skb = skb_copy(skb, GFP_ATOMIC);
 851                         if (!skb)
 852                                 return NET_RX_DROP;
 853                         unicast_packet = (struct unicast_packet *) skb->data;
 854                         kfree_skb(skb_old);
 855                 }
 856                 /* decrement ttl */
 857                 unicast_packet->ttl--;
 858
 859                 /* route it */
 860                 send_skb_packet(skb, batman_if, dstaddr);
 861                 ret = NET_RX_SUCCESS;
 862
 863         } else
 864                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 865
 866         return ret;
 867 }
 868
 869
 870 int recv_bcast_packet(struct sk_buff *skb)
 871 {
 872         struct orig_node *orig_node;
 873         struct bcast_packet *bcast_packet;
 874         struct ethhdr *ethhdr;
 875         int hdr_size = sizeof(struct bcast_packet);
 876         unsigned long flags;
 877
 878         /* drop packet if it has not necessary minimum size */
 879         if (skb_headlen(skb) < hdr_size)
 880                 return NET_RX_DROP;
 881
 882         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 883
 884         /* packet with broadcast indication but unicast recipient */
 885         if (!is_bcast(ethhdr->h_dest))
 886                 return NET_RX_DROP;
 887
 888         /* packet with broadcast sender address */
 889         if (is_bcast(ethhdr->h_source))
 890                 return NET_RX_DROP;
 891
 892         /* ignore broadcasts sent by myself */
 893         if (is_my_mac(ethhdr->h_source))
 894                 return NET_RX_DROP;
 895
 896         bcast_packet = (struct bcast_packet *)skb->data;
 897
 898         /* ignore broadcasts originated by myself */
 899         if (is_my_mac(bcast_packet->orig))
 900                 return NET_RX_DROP;
 901
 902         spin_lock_irqsave(&orig_hash_lock, flags);
 903         orig_node = ((struct orig_node *)
 904                      hash_find(orig_hash, bcast_packet->orig));
 905
 906         if (orig_node == NULL) {
 907                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 908                 return NET_RX_DROP;
 909         }
 910
 911         /* check flood history */
 912         if (get_bit_status(orig_node->bcast_bits,
 913                            orig_node->last_bcast_seqno,
 914                            ntohs(bcast_packet->seqno))) {
 915                 spin_unlock_irqrestore(&orig_hash_lock, flags);
 916                 return NET_RX_DROP;
 917         }
 918
 919         /* mark broadcast in flood history */
 920         if (bit_get_packet(orig_node->bcast_bits,
 921                            ntohs(bcast_packet->seqno) -
 922                            orig_node->last_bcast_seqno, 1))
 923                 orig_node->last_bcast_seqno = ntohs(bcast_packet->seqno);
 924
 925         spin_unlock_irqrestore(&orig_hash_lock, flags);
 926
 927         /* rebroadcast packet */
 928         add_bcast_packet_to_list(skb);
 929
 930         /* broadcast for me */
 931         interface_rx(skb, hdr_size);
 932
 933         return NET_RX_SUCCESS;
 934 }
 935
 936 int recv_vis_packet(struct sk_buff *skb)
 937 {
 938         struct vis_packet *vis_packet;
 939         struct ethhdr *ethhdr;
 940         struct bat_priv *bat_priv;
 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         /* FIXME: each batman_if will be attached to a softif */
 961         bat_priv = netdev_priv(soft_device);
 962
 963         switch (vis_packet->vis_type) {
 964         case VIS_TYPE_SERVER_SYNC:
 965                 /* TODO: handle fragmented skbs properly */
 966                 receive_server_sync_packet(bat_priv, vis_packet,
 967                                            skb_headlen(skb));
 968                 break;
 969
 970         case VIS_TYPE_CLIENT_UPDATE:
 971                 /* TODO: handle fragmented skbs properly */
 972                 receive_client_update_packet(bat_priv, vis_packet,
 973                                              skb_headlen(skb));
 974                 break;
 975
 976         default:        /* ignore unknown packet */
 977                 break;
 978         }
 979
 980         /* We take a copy of the data in the packet, so we should
 981            always free the skbuf. */
 982         return NET_RX_DROP;
 983 }