1 /* 2 * Copyright (C) 2007-2011 B.A.T.M.A.N. contributors: 3 * 4 * Marek Lindner, Simon Wunderlich 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of version 2 of the GNU General Public 8 * License as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, but 11 * WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 * General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 18 * 02110-1301, USA 19 * 20 */ 21 22 #include "main.h" 23 #include "bat_ogm.h" 24 #include "translation-table.h" 25 #include "ring_buffer.h" 26 #include "originator.h" 27 #include "routing.h" 28 #include "gateway_common.h" 29 #include "gateway_client.h" 30 #include "hard-interface.h" 31 #include "send.h" 32 33 void bat_ogm_init(struct hard_iface *hard_iface) 34 { 35 struct batman_ogm_packet *batman_ogm_packet; 36 37 hard_iface->packet_len = BATMAN_OGM_LEN; 38 hard_iface->packet_buff = kmalloc(hard_iface->packet_len, GFP_ATOMIC); 39 40 batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff; 41 batman_ogm_packet->packet_type = BAT_OGM; 42 batman_ogm_packet->version = COMPAT_VERSION; 43 batman_ogm_packet->flags = NO_FLAGS; 44 batman_ogm_packet->ttl = 2; 45 batman_ogm_packet->tq = TQ_MAX_VALUE; 46 batman_ogm_packet->tt_num_changes = 0; 47 batman_ogm_packet->ttvn = 0; 48 } 49 50 void bat_ogm_init_primary(struct hard_iface *hard_iface) 51 { 52 struct batman_ogm_packet *batman_ogm_packet; 53 54 batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff; 55 batman_ogm_packet->flags = PRIMARIES_FIRST_HOP; 56 batman_ogm_packet->ttl = TTL; 57 } 58 59 void bat_ogm_update_mac(struct hard_iface *hard_iface) 60 { 61 struct batman_ogm_packet *batman_ogm_packet; 62 63 batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff; 64 memcpy(batman_ogm_packet->orig, 65 hard_iface->net_dev->dev_addr, ETH_ALEN); 66 memcpy(batman_ogm_packet->prev_sender, 67 hard_iface->net_dev->dev_addr, ETH_ALEN); 68 } 69 70 /* when do we schedule our own ogm to be sent */ 71 static unsigned long bat_ogm_emit_send_time(const struct bat_priv *bat_priv) 72 { 73 return jiffies + msecs_to_jiffies( 74 atomic_read(&bat_priv->orig_interval) - 75 JITTER + (random32() % 2*JITTER)); 76 } 77 78 /* when do we schedule a ogm packet to be sent */ 79 static unsigned long bat_ogm_fwd_send_time(void) 80 { 81 return jiffies + msecs_to_jiffies(random32() % (JITTER/2)); 82 } 83 84 /* apply hop penalty for a normal link */ 85 static uint8_t hop_penalty(uint8_t tq, const struct bat_priv *bat_priv) 86 { 87 int hop_penalty = atomic_read(&bat_priv->hop_penalty); 88 return (tq * (TQ_MAX_VALUE - hop_penalty)) / (TQ_MAX_VALUE); 89 } 90 91 /* is there another aggregated packet here? */ 92 static int bat_ogm_aggr_packet(int buff_pos, int packet_len, 93 int tt_num_changes) 94 { 95 int next_buff_pos = buff_pos + BATMAN_OGM_LEN + tt_len(tt_num_changes); 96 97 return (next_buff_pos <= packet_len) && 98 (next_buff_pos <= MAX_AGGREGATION_BYTES); 99 } 100 101 /* send a batman ogm to a given interface */ 102 static void bat_ogm_send_to_if(struct forw_packet *forw_packet, 103 struct hard_iface *hard_iface) 104 { 105 struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface); 106 char *fwd_str; 107 uint8_t packet_num; 108 int16_t buff_pos; 109 struct batman_ogm_packet *batman_ogm_packet; 110 struct sk_buff *skb; 111 112 if (hard_iface->if_status != IF_ACTIVE) 113 return; 114 115 packet_num = 0; 116 buff_pos = 0; 117 batman_ogm_packet = (struct batman_ogm_packet *)forw_packet->skb->data; 118 119 /* adjust all flags and log packets */ 120 while (bat_ogm_aggr_packet(buff_pos, forw_packet->packet_len, 121 batman_ogm_packet->tt_num_changes)) { 122 123 /* we might have aggregated direct link packets with an 124 * ordinary base packet */ 125 if ((forw_packet->direct_link_flags & (1 << packet_num)) && 126 (forw_packet->if_incoming == hard_iface)) 127 batman_ogm_packet->flags |= DIRECTLINK; 128 else 129 batman_ogm_packet->flags &= ~DIRECTLINK; 130 131 fwd_str = (packet_num > 0 ? "Forwarding" : (forw_packet->own ? 132 "Sending own" : 133 "Forwarding")); 134 bat_dbg(DBG_BATMAN, bat_priv, 135 "%s %spacket (originator %pM, seqno %d, TQ %d, TTL %d," 136 " IDF %s, ttvn %d) on interface %s [%pM]\n", 137 fwd_str, (packet_num > 0 ? "aggregated " : ""), 138 batman_ogm_packet->orig, 139 ntohl(batman_ogm_packet->seqno), 140 batman_ogm_packet->tq, batman_ogm_packet->ttl, 141 (batman_ogm_packet->flags & DIRECTLINK ? 142 "on" : "off"), 143 batman_ogm_packet->ttvn, hard_iface->net_dev->name, 144 hard_iface->net_dev->dev_addr); 145 146 buff_pos += BATMAN_OGM_LEN + 147 tt_len(batman_ogm_packet->tt_num_changes); 148 packet_num++; 149 batman_ogm_packet = (struct batman_ogm_packet *) 150 (forw_packet->skb->data + buff_pos); 151 } 152 153 /* create clone because function is called more than once */ 154 skb = skb_clone(forw_packet->skb, GFP_ATOMIC); 155 if (skb) 156 send_skb_packet(skb, hard_iface, broadcast_addr); 157 } 158 159 /* send a batman ogm packet */ 160 void bat_ogm_emit(struct forw_packet *forw_packet) 161 { 162 struct hard_iface *hard_iface; 163 struct net_device *soft_iface; 164 struct bat_priv *bat_priv; 165 struct hard_iface *primary_if = NULL; 166 struct batman_ogm_packet *batman_ogm_packet; 167 unsigned char directlink; 168 169 batman_ogm_packet = (struct batman_ogm_packet *) 170 (forw_packet->skb->data); 171 directlink = (batman_ogm_packet->flags & DIRECTLINK ? 1 : 0); 172 173 if (!forw_packet->if_incoming) { 174 pr_err("Error - can't forward packet: incoming iface not " 175 "specified\n"); 176 goto out; 177 } 178 179 soft_iface = forw_packet->if_incoming->soft_iface; 180 bat_priv = netdev_priv(soft_iface); 181 182 if (forw_packet->if_incoming->if_status != IF_ACTIVE) 183 goto out; 184 185 primary_if = primary_if_get_selected(bat_priv); 186 if (!primary_if) 187 goto out; 188 189 /* multihomed peer assumed */ 190 /* non-primary OGMs are only broadcasted on their interface */ 191 if ((directlink && (batman_ogm_packet->ttl == 1)) || 192 (forw_packet->own && (forw_packet->if_incoming != primary_if))) { 193 194 /* FIXME: what about aggregated packets ? */ 195 bat_dbg(DBG_BATMAN, bat_priv, 196 "%s packet (originator %pM, seqno %d, TTL %d) " 197 "on interface %s [%pM]\n", 198 (forw_packet->own ? "Sending own" : "Forwarding"), 199 batman_ogm_packet->orig, 200 ntohl(batman_ogm_packet->seqno), 201 batman_ogm_packet->ttl, 202 forw_packet->if_incoming->net_dev->name, 203 forw_packet->if_incoming->net_dev->dev_addr); 204 205 /* skb is only used once and than forw_packet is free'd */ 206 send_skb_packet(forw_packet->skb, forw_packet->if_incoming, 207 broadcast_addr); 208 forw_packet->skb = NULL; 209 210 goto out; 211 } 212 213 /* broadcast on every interface */ 214 rcu_read_lock(); 215 list_for_each_entry_rcu(hard_iface, &hardif_list, list) { 216 if (hard_iface->soft_iface != soft_iface) 217 continue; 218 219 bat_ogm_send_to_if(forw_packet, hard_iface); 220 } 221 rcu_read_unlock(); 222 223 out: 224 if (primary_if) 225 hardif_free_ref(primary_if); 226 } 227 228 /* return true if new_packet can be aggregated with forw_packet */ 229 static bool bat_ogm_can_aggregate(const struct batman_ogm_packet 230 *new_batman_ogm_packet, 231 struct bat_priv *bat_priv, 232 int packet_len, unsigned long send_time, 233 bool directlink, 234 const struct hard_iface *if_incoming, 235 const struct forw_packet *forw_packet) 236 { 237 struct batman_ogm_packet *batman_ogm_packet; 238 int aggregated_bytes = forw_packet->packet_len + packet_len; 239 struct hard_iface *primary_if = NULL; 240 bool res = false; 241 242 batman_ogm_packet = (struct batman_ogm_packet *)forw_packet->skb->data; 243 244 /** 245 * we can aggregate the current packet to this aggregated packet 246 * if: 247 * 248 * - the send time is within our MAX_AGGREGATION_MS time 249 * - the resulting packet wont be bigger than 250 * MAX_AGGREGATION_BYTES 251 */ 252 253 if (time_before(send_time, forw_packet->send_time) && 254 time_after_eq(send_time + msecs_to_jiffies(MAX_AGGREGATION_MS), 255 forw_packet->send_time) && 256 (aggregated_bytes <= MAX_AGGREGATION_BYTES)) { 257 258 /** 259 * check aggregation compatibility 260 * -> direct link packets are broadcasted on 261 * their interface only 262 * -> aggregate packet if the current packet is 263 * a "global" packet as well as the base 264 * packet 265 */ 266 267 primary_if = primary_if_get_selected(bat_priv); 268 if (!primary_if) 269 goto out; 270 271 /* packets without direct link flag and high TTL 272 * are flooded through the net */ 273 if ((!directlink) && 274 (!(batman_ogm_packet->flags & DIRECTLINK)) && 275 (batman_ogm_packet->ttl != 1) && 276 277 /* own packets originating non-primary 278 * interfaces leave only that interface */ 279 ((!forw_packet->own) || 280 (forw_packet->if_incoming == primary_if))) { 281 res = true; 282 goto out; 283 } 284 285 /* if the incoming packet is sent via this one 286 * interface only - we still can aggregate */ 287 if ((directlink) && 288 (new_batman_ogm_packet->ttl == 1) && 289 (forw_packet->if_incoming == if_incoming) && 290 291 /* packets from direct neighbors or 292 * own secondary interface packets 293 * (= secondary interface packets in general) */ 294 (batman_ogm_packet->flags & DIRECTLINK || 295 (forw_packet->own && 296 forw_packet->if_incoming != primary_if))) { 297 res = true; 298 goto out; 299 } 300 } 301 302 out: 303 if (primary_if) 304 hardif_free_ref(primary_if); 305 return res; 306 } 307 308 /* create a new aggregated packet and add this packet to it */ 309 static void bat_ogm_aggregate_new(const unsigned char *packet_buff, 310 int packet_len, unsigned long send_time, 311 bool direct_link, 312 struct hard_iface *if_incoming, 313 int own_packet) 314 { 315 struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface); 316 struct forw_packet *forw_packet_aggr; 317 unsigned char *skb_buff; 318 319 if (!atomic_inc_not_zero(&if_incoming->refcount)) 320 return; 321 322 /* own packet should always be scheduled */ 323 if (!own_packet) { 324 if (!atomic_dec_not_zero(&bat_priv->batman_queue_left)) { 325 bat_dbg(DBG_BATMAN, bat_priv, 326 "batman packet queue full\n"); 327 goto out; 328 } 329 } 330 331 forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC); 332 if (!forw_packet_aggr) { 333 if (!own_packet) 334 atomic_inc(&bat_priv->batman_queue_left); 335 goto out; 336 } 337 338 if ((atomic_read(&bat_priv->aggregated_ogms)) && 339 (packet_len < MAX_AGGREGATION_BYTES)) 340 forw_packet_aggr->skb = dev_alloc_skb(MAX_AGGREGATION_BYTES + 341 sizeof(struct ethhdr)); 342 else 343 forw_packet_aggr->skb = dev_alloc_skb(packet_len + 344 sizeof(struct ethhdr)); 345 346 if (!forw_packet_aggr->skb) { 347 if (!own_packet) 348 atomic_inc(&bat_priv->batman_queue_left); 349 kfree(forw_packet_aggr); 350 goto out; 351 } 352 skb_reserve(forw_packet_aggr->skb, sizeof(struct ethhdr)); 353 354 INIT_HLIST_NODE(&forw_packet_aggr->list); 355 356 skb_buff = skb_put(forw_packet_aggr->skb, packet_len); 357 forw_packet_aggr->packet_len = packet_len; 358 memcpy(skb_buff, packet_buff, packet_len); 359 360 forw_packet_aggr->own = own_packet; 361 forw_packet_aggr->if_incoming = if_incoming; 362 forw_packet_aggr->num_packets = 0; 363 forw_packet_aggr->direct_link_flags = NO_FLAGS; 364 forw_packet_aggr->send_time = send_time; 365 366 /* save packet direct link flag status */ 367 if (direct_link) 368 forw_packet_aggr->direct_link_flags |= 1; 369 370 /* add new packet to packet list */ 371 spin_lock_bh(&bat_priv->forw_bat_list_lock); 372 hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list); 373 spin_unlock_bh(&bat_priv->forw_bat_list_lock); 374 375 /* start timer for this packet */ 376 INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work, 377 send_outstanding_bat_ogm_packet); 378 queue_delayed_work(bat_event_workqueue, 379 &forw_packet_aggr->delayed_work, 380 send_time - jiffies); 381 382 return; 383 out: 384 hardif_free_ref(if_incoming); 385 } 386 387 /* aggregate a new packet into the existing ogm packet */ 388 static void bat_ogm_aggregate(struct forw_packet *forw_packet_aggr, 389 const unsigned char *packet_buff, 390 int packet_len, bool direct_link) 391 { 392 unsigned char *skb_buff; 393 394 skb_buff = skb_put(forw_packet_aggr->skb, packet_len); 395 memcpy(skb_buff, packet_buff, packet_len); 396 forw_packet_aggr->packet_len += packet_len; 397 forw_packet_aggr->num_packets++; 398 399 /* save packet direct link flag status */ 400 if (direct_link) 401 forw_packet_aggr->direct_link_flags |= 402 (1 << forw_packet_aggr->num_packets); 403 } 404 405 static void bat_ogm_queue_add(struct bat_priv *bat_priv, 406 unsigned char *packet_buff, 407 int packet_len, struct hard_iface *if_incoming, 408 int own_packet, unsigned long send_time) 409 { 410 /** 411 * _aggr -> pointer to the packet we want to aggregate with 412 * _pos -> pointer to the position in the queue 413 */ 414 struct forw_packet *forw_packet_aggr = NULL, *forw_packet_pos = NULL; 415 struct hlist_node *tmp_node; 416 struct batman_ogm_packet *batman_ogm_packet; 417 bool direct_link; 418 419 batman_ogm_packet = (struct batman_ogm_packet *)packet_buff; 420 direct_link = batman_ogm_packet->flags & DIRECTLINK ? 1 : 0; 421 422 /* find position for the packet in the forward queue */ 423 spin_lock_bh(&bat_priv->forw_bat_list_lock); 424 /* own packets are not to be aggregated */ 425 if ((atomic_read(&bat_priv->aggregated_ogms)) && (!own_packet)) { 426 hlist_for_each_entry(forw_packet_pos, tmp_node, 427 &bat_priv->forw_bat_list, list) { 428 if (bat_ogm_can_aggregate(batman_ogm_packet, 429 bat_priv, packet_len, 430 send_time, direct_link, 431 if_incoming, 432 forw_packet_pos)) { 433 forw_packet_aggr = forw_packet_pos; 434 break; 435 } 436 } 437 } 438 439 /* nothing to aggregate with - either aggregation disabled or no 440 * suitable aggregation packet found */ 441 if (!forw_packet_aggr) { 442 /* the following section can run without the lock */ 443 spin_unlock_bh(&bat_priv->forw_bat_list_lock); 444 445 /** 446 * if we could not aggregate this packet with one of the others 447 * we hold it back for a while, so that it might be aggregated 448 * later on 449 */ 450 if ((!own_packet) && 451 (atomic_read(&bat_priv->aggregated_ogms))) 452 send_time += msecs_to_jiffies(MAX_AGGREGATION_MS); 453 454 bat_ogm_aggregate_new(packet_buff, packet_len, 455 send_time, direct_link, 456 if_incoming, own_packet); 457 } else { 458 bat_ogm_aggregate(forw_packet_aggr, packet_buff, packet_len, 459 direct_link); 460 spin_unlock_bh(&bat_priv->forw_bat_list_lock); 461 } 462 } 463 464 static void bat_ogm_forward(struct orig_node *orig_node, 465 const struct ethhdr *ethhdr, 466 struct batman_ogm_packet *batman_ogm_packet, 467 int directlink, struct hard_iface *if_incoming) 468 { 469 struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface); 470 struct neigh_node *router; 471 uint8_t in_tq, in_ttl, tq_avg = 0; 472 uint8_t tt_num_changes; 473 474 if (batman_ogm_packet->ttl <= 1) { 475 bat_dbg(DBG_BATMAN, bat_priv, "ttl exceeded\n"); 476 return; 477 } 478 479 router = orig_node_get_router(orig_node); 480 481 in_tq = batman_ogm_packet->tq; 482 in_ttl = batman_ogm_packet->ttl; 483 tt_num_changes = batman_ogm_packet->tt_num_changes; 484 485 batman_ogm_packet->ttl--; 486 memcpy(batman_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN); 487 488 /* rebroadcast tq of our best ranking neighbor to ensure the rebroadcast 489 * of our best tq value */ 490 if (router && router->tq_avg != 0) { 491 492 /* rebroadcast ogm of best ranking neighbor as is */ 493 if (!compare_eth(router->addr, ethhdr->h_source)) { 494 batman_ogm_packet->tq = router->tq_avg; 495 496 if (router->last_ttl) 497 batman_ogm_packet->ttl = router->last_ttl - 1; 498 } 499 500 tq_avg = router->tq_avg; 501 } 502 503 if (router) 504 neigh_node_free_ref(router); 505 506 /* apply hop penalty */ 507 batman_ogm_packet->tq = hop_penalty(batman_ogm_packet->tq, bat_priv); 508 509 bat_dbg(DBG_BATMAN, bat_priv, 510 "Forwarding packet: tq_orig: %i, tq_avg: %i, " 511 "tq_forw: %i, ttl_orig: %i, ttl_forw: %i\n", 512 in_tq, tq_avg, batman_ogm_packet->tq, in_ttl - 1, 513 batman_ogm_packet->ttl); 514 515 batman_ogm_packet->seqno = htonl(batman_ogm_packet->seqno); 516 batman_ogm_packet->tt_crc = htons(batman_ogm_packet->tt_crc); 517 518 /* switch of primaries first hop flag when forwarding */ 519 batman_ogm_packet->flags &= ~PRIMARIES_FIRST_HOP; 520 if (directlink) 521 batman_ogm_packet->flags |= DIRECTLINK; 522 else 523 batman_ogm_packet->flags &= ~DIRECTLINK; 524 525 bat_ogm_queue_add(bat_priv, (unsigned char *)batman_ogm_packet, 526 BATMAN_OGM_LEN + tt_len(tt_num_changes), 527 if_incoming, 0, bat_ogm_fwd_send_time()); 528 } 529 530 void bat_ogm_schedule(struct hard_iface *hard_iface, int tt_num_changes) 531 { 532 struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface); 533 struct batman_ogm_packet *batman_ogm_packet; 534 struct hard_iface *primary_if; 535 int vis_server; 536 537 vis_server = atomic_read(&bat_priv->vis_mode); 538 primary_if = primary_if_get_selected(bat_priv); 539 540 batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff; 541 542 /* change sequence number to network order */ 543 batman_ogm_packet->seqno = 544 htonl((uint32_t)atomic_read(&hard_iface->seqno)); 545 546 batman_ogm_packet->ttvn = atomic_read(&bat_priv->ttvn); 547 batman_ogm_packet->tt_crc = htons((uint16_t) 548 atomic_read(&bat_priv->tt_crc)); 549 if (tt_num_changes >= 0) 550 batman_ogm_packet->tt_num_changes = tt_num_changes; 551 552 if (vis_server == VIS_TYPE_SERVER_SYNC) 553 batman_ogm_packet->flags |= VIS_SERVER; 554 else 555 batman_ogm_packet->flags &= ~VIS_SERVER; 556 557 if ((hard_iface == primary_if) && 558 (atomic_read(&bat_priv->gw_mode) == GW_MODE_SERVER)) 559 batman_ogm_packet->gw_flags = 560 (uint8_t)atomic_read(&bat_priv->gw_bandwidth); 561 else 562 batman_ogm_packet->gw_flags = NO_FLAGS; 563 564 atomic_inc(&hard_iface->seqno); 565 566 slide_own_bcast_window(hard_iface); 567 bat_ogm_queue_add(bat_priv, hard_iface->packet_buff, 568 hard_iface->packet_len, hard_iface, 1, 569 bat_ogm_emit_send_time(bat_priv)); 570 571 if (primary_if) 572 hardif_free_ref(primary_if); 573 } 574 575 static void bat_ogm_orig_update(struct bat_priv *bat_priv, 576 struct orig_node *orig_node, 577 const struct ethhdr *ethhdr, 578 const struct batman_ogm_packet 579 *batman_ogm_packet, 580 struct hard_iface *if_incoming, 581 const unsigned char *tt_buff, int is_duplicate) 582 { 583 struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL; 584 struct neigh_node *router = NULL; 585 struct orig_node *orig_node_tmp; 586 struct hlist_node *node; 587 uint8_t bcast_own_sum_orig, bcast_own_sum_neigh; 588 589 bat_dbg(DBG_BATMAN, bat_priv, "update_originator(): " 590 "Searching and updating originator entry of received packet\n"); 591 592 rcu_read_lock(); 593 hlist_for_each_entry_rcu(tmp_neigh_node, node, 594 &orig_node->neigh_list, list) { 595 if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) && 596 (tmp_neigh_node->if_incoming == if_incoming) && 597 atomic_inc_not_zero(&tmp_neigh_node->refcount)) { 598 if (neigh_node) 599 neigh_node_free_ref(neigh_node); 600 neigh_node = tmp_neigh_node; 601 continue; 602 } 603 604 if (is_duplicate) 605 continue; 606 607 spin_lock_bh(&tmp_neigh_node->tq_lock); 608 ring_buffer_set(tmp_neigh_node->tq_recv, 609 &tmp_neigh_node->tq_index, 0); 610 tmp_neigh_node->tq_avg = 611 ring_buffer_avg(tmp_neigh_node->tq_recv); 612 spin_unlock_bh(&tmp_neigh_node->tq_lock); 613 } 614 615 if (!neigh_node) { 616 struct orig_node *orig_tmp; 617 618 orig_tmp = get_orig_node(bat_priv, ethhdr->h_source); 619 if (!orig_tmp) 620 goto unlock; 621 622 neigh_node = create_neighbor(orig_node, orig_tmp, 623 ethhdr->h_source, if_incoming); 624 625 orig_node_free_ref(orig_tmp); 626 if (!neigh_node) 627 goto unlock; 628 } else 629 bat_dbg(DBG_BATMAN, bat_priv, 630 "Updating existing last-hop neighbor of originator\n"); 631 632 rcu_read_unlock(); 633 634 orig_node->flags = batman_ogm_packet->flags; 635 neigh_node->last_valid = jiffies; 636 637 spin_lock_bh(&neigh_node->tq_lock); 638 ring_buffer_set(neigh_node->tq_recv, 639 &neigh_node->tq_index, 640 batman_ogm_packet->tq); 641 neigh_node->tq_avg = ring_buffer_avg(neigh_node->tq_recv); 642 spin_unlock_bh(&neigh_node->tq_lock); 643 644 if (!is_duplicate) { 645 orig_node->last_ttl = batman_ogm_packet->ttl; 646 neigh_node->last_ttl = batman_ogm_packet->ttl; 647 } 648 649 bonding_candidate_add(orig_node, neigh_node); 650 651 /* if this neighbor already is our next hop there is nothing 652 * to change */ 653 router = orig_node_get_router(orig_node); 654 if (router == neigh_node) 655 goto update_tt; 656 657 /* if this neighbor does not offer a better TQ we won't consider it */ 658 if (router && (router->tq_avg > neigh_node->tq_avg)) 659 goto update_tt; 660 661 /* if the TQ is the same and the link not more symmetric we 662 * won't consider it either */ 663 if (router && (neigh_node->tq_avg == router->tq_avg)) { 664 orig_node_tmp = router->orig_node; 665 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock); 666 bcast_own_sum_orig = 667 orig_node_tmp->bcast_own_sum[if_incoming->if_num]; 668 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock); 669 670 orig_node_tmp = neigh_node->orig_node; 671 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock); 672 bcast_own_sum_neigh = 673 orig_node_tmp->bcast_own_sum[if_incoming->if_num]; 674 spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock); 675 676 if (bcast_own_sum_orig >= bcast_own_sum_neigh) 677 goto update_tt; 678 } 679 680 update_route(bat_priv, orig_node, neigh_node); 681 682 update_tt: 683 /* I have to check for transtable changes only if the OGM has been 684 * sent through a primary interface */ 685 if (((batman_ogm_packet->orig != ethhdr->h_source) && 686 (batman_ogm_packet->ttl > 2)) || 687 (batman_ogm_packet->flags & PRIMARIES_FIRST_HOP)) 688 tt_update_orig(bat_priv, orig_node, tt_buff, 689 batman_ogm_packet->tt_num_changes, 690 batman_ogm_packet->ttvn, 691 batman_ogm_packet->tt_crc); 692 693 if (orig_node->gw_flags != batman_ogm_packet->gw_flags) 694 gw_node_update(bat_priv, orig_node, 695 batman_ogm_packet->gw_flags); 696 697 orig_node->gw_flags = batman_ogm_packet->gw_flags; 698 699 /* restart gateway selection if fast or late switching was enabled */ 700 if ((orig_node->gw_flags) && 701 (atomic_read(&bat_priv->gw_mode) == GW_MODE_CLIENT) && 702 (atomic_read(&bat_priv->gw_sel_class) > 2)) 703 gw_check_election(bat_priv, orig_node); 704 705 goto out; 706 707 unlock: 708 rcu_read_unlock(); 709 out: 710 if (neigh_node) 711 neigh_node_free_ref(neigh_node); 712 if (router) 713 neigh_node_free_ref(router); 714 } 715 716 static int bat_ogm_calc_tq(struct orig_node *orig_node, 717 struct orig_node *orig_neigh_node, 718 struct batman_ogm_packet *batman_ogm_packet, 719 struct hard_iface *if_incoming) 720 { 721 struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface); 722 struct neigh_node *neigh_node = NULL, *tmp_neigh_node; 723 struct hlist_node *node; 724 uint8_t total_count; 725 uint8_t orig_eq_count, neigh_rq_count, tq_own; 726 int tq_asym_penalty, ret = 0; 727 728 /* find corresponding one hop neighbor */ 729 rcu_read_lock(); 730 hlist_for_each_entry_rcu(tmp_neigh_node, node, 731 &orig_neigh_node->neigh_list, list) { 732 733 if (!compare_eth(tmp_neigh_node->addr, orig_neigh_node->orig)) 734 continue; 735 736 if (tmp_neigh_node->if_incoming != if_incoming) 737 continue; 738 739 if (!atomic_inc_not_zero(&tmp_neigh_node->refcount)) 740 continue; 741 742 neigh_node = tmp_neigh_node; 743 break; 744 } 745 rcu_read_unlock(); 746 747 if (!neigh_node) 748 neigh_node = create_neighbor(orig_neigh_node, 749 orig_neigh_node, 750 orig_neigh_node->orig, 751 if_incoming); 752 753 if (!neigh_node) 754 goto out; 755 756 /* if orig_node is direct neighbor update neigh_node last_valid */ 757 if (orig_node == orig_neigh_node) 758 neigh_node->last_valid = jiffies; 759 760 orig_node->last_valid = jiffies; 761 762 /* find packet count of corresponding one hop neighbor */ 763 spin_lock_bh(&orig_node->ogm_cnt_lock); 764 orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num]; 765 neigh_rq_count = neigh_node->real_packet_count; 766 spin_unlock_bh(&orig_node->ogm_cnt_lock); 767 768 /* pay attention to not get a value bigger than 100 % */ 769 total_count = (orig_eq_count > neigh_rq_count ? 770 neigh_rq_count : orig_eq_count); 771 772 /* if we have too few packets (too less data) we set tq_own to zero */ 773 /* if we receive too few packets it is not considered bidirectional */ 774 if ((total_count < TQ_LOCAL_BIDRECT_SEND_MINIMUM) || 775 (neigh_rq_count < TQ_LOCAL_BIDRECT_RECV_MINIMUM)) 776 tq_own = 0; 777 else 778 /* neigh_node->real_packet_count is never zero as we 779 * only purge old information when getting new 780 * information */ 781 tq_own = (TQ_MAX_VALUE * total_count) / neigh_rq_count; 782 783 /* 784 * 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does 785 * affect the nearly-symmetric links only a little, but 786 * punishes asymmetric links more. This will give a value 787 * between 0 and TQ_MAX_VALUE 788 */ 789 tq_asym_penalty = TQ_MAX_VALUE - (TQ_MAX_VALUE * 790 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) * 791 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) * 792 (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count)) / 793 (TQ_LOCAL_WINDOW_SIZE * 794 TQ_LOCAL_WINDOW_SIZE * 795 TQ_LOCAL_WINDOW_SIZE); 796 797 batman_ogm_packet->tq = ((batman_ogm_packet->tq * tq_own 798 * tq_asym_penalty) / 799 (TQ_MAX_VALUE * TQ_MAX_VALUE)); 800 801 bat_dbg(DBG_BATMAN, bat_priv, 802 "bidirectional: " 803 "orig = %-15pM neigh = %-15pM => own_bcast = %2i, " 804 "real recv = %2i, local tq: %3i, asym_penalty: %3i, " 805 "total tq: %3i\n", 806 orig_node->orig, orig_neigh_node->orig, total_count, 807 neigh_rq_count, tq_own, tq_asym_penalty, batman_ogm_packet->tq); 808 809 /* if link has the minimum required transmission quality 810 * consider it bidirectional */ 811 if (batman_ogm_packet->tq >= TQ_TOTAL_BIDRECT_LIMIT) 812 ret = 1; 813 814 out: 815 if (neigh_node) 816 neigh_node_free_ref(neigh_node); 817 return ret; 818 } 819 820 /* processes a batman packet for all interfaces, adjusts the sequence number and 821 * finds out whether it is a duplicate. 822 * returns: 823 * 1 the packet is a duplicate 824 * 0 the packet has not yet been received 825 * -1 the packet is old and has been received while the seqno window 826 * was protected. Caller should drop it. 827 */ 828 static int bat_ogm_update_seqnos(const struct ethhdr *ethhdr, 829 const struct batman_ogm_packet 830 *batman_ogm_packet, 831 const struct hard_iface *if_incoming) 832 { 833 struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface); 834 struct orig_node *orig_node; 835 struct neigh_node *tmp_neigh_node; 836 struct hlist_node *node; 837 int is_duplicate = 0; 838 int32_t seq_diff; 839 int need_update = 0; 840 int set_mark, ret = -1; 841 842 orig_node = get_orig_node(bat_priv, batman_ogm_packet->orig); 843 if (!orig_node) 844 return 0; 845 846 spin_lock_bh(&orig_node->ogm_cnt_lock); 847 seq_diff = batman_ogm_packet->seqno - orig_node->last_real_seqno; 848 849 /* signalize caller that the packet is to be dropped. */ 850 if (window_protected(bat_priv, seq_diff, 851 &orig_node->batman_seqno_reset)) 852 goto out; 853 854 rcu_read_lock(); 855 hlist_for_each_entry_rcu(tmp_neigh_node, node, 856 &orig_node->neigh_list, list) { 857 858 is_duplicate |= get_bit_status(tmp_neigh_node->real_bits, 859 orig_node->last_real_seqno, 860 batman_ogm_packet->seqno); 861 862 if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) && 863 (tmp_neigh_node->if_incoming == if_incoming)) 864 set_mark = 1; 865 else 866 set_mark = 0; 867 868 /* if the window moved, set the update flag. */ 869 need_update |= bit_get_packet(bat_priv, 870 tmp_neigh_node->real_bits, 871 seq_diff, set_mark); 872 873 tmp_neigh_node->real_packet_count = 874 bit_packet_count(tmp_neigh_node->real_bits); 875 } 876 rcu_read_unlock(); 877 878 if (need_update) { 879 bat_dbg(DBG_BATMAN, bat_priv, 880 "updating last_seqno: old %d, new %d\n", 881 orig_node->last_real_seqno, batman_ogm_packet->seqno); 882 orig_node->last_real_seqno = batman_ogm_packet->seqno; 883 } 884 885 ret = is_duplicate; 886 887 out: 888 spin_unlock_bh(&orig_node->ogm_cnt_lock); 889 orig_node_free_ref(orig_node); 890 return ret; 891 } 892 893 static void bat_ogm_process(const struct ethhdr *ethhdr, 894 struct batman_ogm_packet *batman_ogm_packet, 895 const unsigned char *tt_buff, 896 struct hard_iface *if_incoming) 897 { 898 struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface); 899 struct hard_iface *hard_iface; 900 struct orig_node *orig_neigh_node, *orig_node; 901 struct neigh_node *router = NULL, *router_router = NULL; 902 struct neigh_node *orig_neigh_router = NULL; 903 int has_directlink_flag; 904 int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0; 905 int is_broadcast = 0, is_bidirectional, is_single_hop_neigh; 906 int is_duplicate; 907 uint32_t if_incoming_seqno; 908 909 /* Silently drop when the batman packet is actually not a 910 * correct packet. 911 * 912 * This might happen if a packet is padded (e.g. Ethernet has a 913 * minimum frame length of 64 byte) and the aggregation interprets 914 * it as an additional length. 915 * 916 * TODO: A more sane solution would be to have a bit in the 917 * batman_ogm_packet to detect whether the packet is the last 918 * packet in an aggregation. Here we expect that the padding 919 * is always zero (or not 0x01) 920 */ 921 if (batman_ogm_packet->packet_type != BAT_OGM) 922 return; 923 924 /* could be changed by schedule_own_packet() */ 925 if_incoming_seqno = atomic_read(&if_incoming->seqno); 926 927 has_directlink_flag = (batman_ogm_packet->flags & DIRECTLINK ? 1 : 0); 928 929 is_single_hop_neigh = (compare_eth(ethhdr->h_source, 930 batman_ogm_packet->orig) ? 1 : 0); 931 932 bat_dbg(DBG_BATMAN, bat_priv, 933 "Received BATMAN packet via NB: %pM, IF: %s [%pM] " 934 "(from OG: %pM, via prev OG: %pM, seqno %d, ttvn %u, " 935 "crc %u, changes %u, td %d, TTL %d, V %d, IDF %d)\n", 936 ethhdr->h_source, if_incoming->net_dev->name, 937 if_incoming->net_dev->dev_addr, batman_ogm_packet->orig, 938 batman_ogm_packet->prev_sender, batman_ogm_packet->seqno, 939 batman_ogm_packet->ttvn, batman_ogm_packet->tt_crc, 940 batman_ogm_packet->tt_num_changes, batman_ogm_packet->tq, 941 batman_ogm_packet->ttl, batman_ogm_packet->version, 942 has_directlink_flag); 943 944 rcu_read_lock(); 945 list_for_each_entry_rcu(hard_iface, &hardif_list, list) { 946 if (hard_iface->if_status != IF_ACTIVE) 947 continue; 948 949 if (hard_iface->soft_iface != if_incoming->soft_iface) 950 continue; 951 952 if (compare_eth(ethhdr->h_source, 953 hard_iface->net_dev->dev_addr)) 954 is_my_addr = 1; 955 956 if (compare_eth(batman_ogm_packet->orig, 957 hard_iface->net_dev->dev_addr)) 958 is_my_orig = 1; 959 960 if (compare_eth(batman_ogm_packet->prev_sender, 961 hard_iface->net_dev->dev_addr)) 962 is_my_oldorig = 1; 963 964 if (is_broadcast_ether_addr(ethhdr->h_source)) 965 is_broadcast = 1; 966 } 967 rcu_read_unlock(); 968 969 if (batman_ogm_packet->version != COMPAT_VERSION) { 970 bat_dbg(DBG_BATMAN, bat_priv, 971 "Drop packet: incompatible batman version (%i)\n", 972 batman_ogm_packet->version); 973 return; 974 } 975 976 if (is_my_addr) { 977 bat_dbg(DBG_BATMAN, bat_priv, 978 "Drop packet: received my own broadcast (sender: %pM" 979 ")\n", 980 ethhdr->h_source); 981 return; 982 } 983 984 if (is_broadcast) { 985 bat_dbg(DBG_BATMAN, bat_priv, "Drop packet: " 986 "ignoring all packets with broadcast source addr (sender: %pM" 987 ")\n", ethhdr->h_source); 988 return; 989 } 990 991 if (is_my_orig) { 992 unsigned long *word; 993 int offset; 994 995 orig_neigh_node = get_orig_node(bat_priv, ethhdr->h_source); 996 if (!orig_neigh_node) 997 return; 998 999 /* neighbor has to indicate direct link and it has to 1000 * come via the corresponding interface */ 1001 /* save packet seqno for bidirectional check */ 1002 if (has_directlink_flag && 1003 compare_eth(if_incoming->net_dev->dev_addr, 1004 batman_ogm_packet->orig)) { 1005 offset = if_incoming->if_num * NUM_WORDS; 1006 1007 spin_lock_bh(&orig_neigh_node->ogm_cnt_lock); 1008 word = &(orig_neigh_node->bcast_own[offset]); 1009 bit_mark(word, 1010 if_incoming_seqno - 1011 batman_ogm_packet->seqno - 2); 1012 orig_neigh_node->bcast_own_sum[if_incoming->if_num] = 1013 bit_packet_count(word); 1014 spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock); 1015 } 1016 1017 bat_dbg(DBG_BATMAN, bat_priv, "Drop packet: " 1018 "originator packet from myself (via neighbor)\n"); 1019 orig_node_free_ref(orig_neigh_node); 1020 return; 1021 } 1022 1023 if (is_my_oldorig) { 1024 bat_dbg(DBG_BATMAN, bat_priv, 1025 "Drop packet: ignoring all rebroadcast echos (sender: " 1026 "%pM)\n", ethhdr->h_source); 1027 return; 1028 } 1029 1030 orig_node = get_orig_node(bat_priv, batman_ogm_packet->orig); 1031 if (!orig_node) 1032 return; 1033 1034 is_duplicate = bat_ogm_update_seqnos(ethhdr, batman_ogm_packet, 1035 if_incoming); 1036 1037 if (is_duplicate == -1) { 1038 bat_dbg(DBG_BATMAN, bat_priv, 1039 "Drop packet: packet within seqno protection time " 1040 "(sender: %pM)\n", ethhdr->h_source); 1041 goto out; 1042 } 1043 1044 if (batman_ogm_packet->tq == 0) { 1045 bat_dbg(DBG_BATMAN, bat_priv, 1046 "Drop packet: originator packet with tq equal 0\n"); 1047 goto out; 1048 } 1049 1050 router = orig_node_get_router(orig_node); 1051 if (router) 1052 router_router = orig_node_get_router(router->orig_node); 1053 1054 /* avoid temporary routing loops */ 1055 if (router && router_router && 1056 (compare_eth(router->addr, batman_ogm_packet->prev_sender)) && 1057 !(compare_eth(batman_ogm_packet->orig, 1058 batman_ogm_packet->prev_sender)) && 1059 (compare_eth(router->addr, router_router->addr))) { 1060 bat_dbg(DBG_BATMAN, bat_priv, 1061 "Drop packet: ignoring all rebroadcast packets that " 1062 "may make me loop (sender: %pM)\n", ethhdr->h_source); 1063 goto out; 1064 } 1065 1066 /* if sender is a direct neighbor the sender mac equals 1067 * originator mac */ 1068 orig_neigh_node = (is_single_hop_neigh ? 1069 orig_node : 1070 get_orig_node(bat_priv, ethhdr->h_source)); 1071 if (!orig_neigh_node) 1072 goto out; 1073 1074 orig_neigh_router = orig_node_get_router(orig_neigh_node); 1075 1076 /* drop packet if sender is not a direct neighbor and if we 1077 * don't route towards it */ 1078 if (!is_single_hop_neigh && (!orig_neigh_router)) { 1079 bat_dbg(DBG_BATMAN, bat_priv, 1080 "Drop packet: OGM via unknown neighbor!\n"); 1081 goto out_neigh; 1082 } 1083 1084 is_bidirectional = bat_ogm_calc_tq(orig_node, orig_neigh_node, 1085 batman_ogm_packet, if_incoming); 1086 1087 bonding_save_primary(orig_node, orig_neigh_node, batman_ogm_packet); 1088 1089 /* update ranking if it is not a duplicate or has the same 1090 * seqno and similar ttl as the non-duplicate */ 1091 if (is_bidirectional && 1092 (!is_duplicate || 1093 ((orig_node->last_real_seqno == batman_ogm_packet->seqno) && 1094 (orig_node->last_ttl - 3 <= batman_ogm_packet->ttl)))) 1095 bat_ogm_orig_update(bat_priv, orig_node, ethhdr, 1096 batman_ogm_packet, if_incoming, 1097 tt_buff, is_duplicate); 1098 1099 /* is single hop (direct) neighbor */ 1100 if (is_single_hop_neigh) { 1101 1102 /* mark direct link on incoming interface */ 1103 bat_ogm_forward(orig_node, ethhdr, batman_ogm_packet, 1104 1, if_incoming); 1105 1106 bat_dbg(DBG_BATMAN, bat_priv, "Forwarding packet: " 1107 "rebroadcast neighbor packet with direct link flag\n"); 1108 goto out_neigh; 1109 } 1110 1111 /* multihop originator */ 1112 if (!is_bidirectional) { 1113 bat_dbg(DBG_BATMAN, bat_priv, 1114 "Drop packet: not received via bidirectional link\n"); 1115 goto out_neigh; 1116 } 1117 1118 if (is_duplicate) { 1119 bat_dbg(DBG_BATMAN, bat_priv, 1120 "Drop packet: duplicate packet received\n"); 1121 goto out_neigh; 1122 } 1123 1124 bat_dbg(DBG_BATMAN, bat_priv, 1125 "Forwarding packet: rebroadcast originator packet\n"); 1126 bat_ogm_forward(orig_node, ethhdr, batman_ogm_packet, 0, if_incoming); 1127 1128 out_neigh: 1129 if ((orig_neigh_node) && (!is_single_hop_neigh)) 1130 orig_node_free_ref(orig_neigh_node); 1131 out: 1132 if (router) 1133 neigh_node_free_ref(router); 1134 if (router_router) 1135 neigh_node_free_ref(router_router); 1136 if (orig_neigh_router) 1137 neigh_node_free_ref(orig_neigh_router); 1138 1139 orig_node_free_ref(orig_node); 1140 } 1141 1142 void bat_ogm_receive(const struct ethhdr *ethhdr, unsigned char *packet_buff, 1143 int packet_len, struct hard_iface *if_incoming) 1144 { 1145 struct batman_ogm_packet *batman_ogm_packet; 1146 int buff_pos = 0; 1147 unsigned char *tt_buff; 1148 1149 batman_ogm_packet = (struct batman_ogm_packet *)packet_buff; 1150 1151 /* unpack the aggregated packets and process them one by one */ 1152 do { 1153 /* network to host order for our 32bit seqno and the 1154 orig_interval */ 1155 batman_ogm_packet->seqno = ntohl(batman_ogm_packet->seqno); 1156 batman_ogm_packet->tt_crc = ntohs(batman_ogm_packet->tt_crc); 1157 1158 tt_buff = packet_buff + buff_pos + BATMAN_OGM_LEN; 1159 1160 bat_ogm_process(ethhdr, batman_ogm_packet, 1161 tt_buff, if_incoming); 1162 1163 buff_pos += BATMAN_OGM_LEN + 1164 tt_len(batman_ogm_packet->tt_num_changes); 1165 1166 batman_ogm_packet = (struct batman_ogm_packet *) 1167 (packet_buff + buff_pos); 1168 } while (bat_ogm_aggr_packet(buff_pos, packet_len, 1169 batman_ogm_packet->tt_num_changes)); 1170 } 1171