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 "hard-interface.h" 24 #include "soft-interface.h" 25 #include "send.h" 26 #include "translation-table.h" 27 #include "routing.h" 28 #include "bat_sysfs.h" 29 #include "originator.h" 30 #include "hash.h" 31 32 #include <linux/if_arp.h> 33 34 35 static int batman_skb_recv(struct sk_buff *skb, 36 struct net_device *dev, 37 struct packet_type *ptype, 38 struct net_device *orig_dev); 39 40 void hardif_free_rcu(struct rcu_head *rcu) 41 { 42 struct hard_iface *hard_iface; 43 44 hard_iface = container_of(rcu, struct hard_iface, rcu); 45 dev_put(hard_iface->net_dev); 46 kfree(hard_iface); 47 } 48 49 struct hard_iface *hardif_get_by_netdev(struct net_device *net_dev) 50 { 51 struct hard_iface *hard_iface; 52 53 rcu_read_lock(); 54 list_for_each_entry_rcu(hard_iface, &hardif_list, list) { 55 if (hard_iface->net_dev == net_dev && 56 atomic_inc_not_zero(&hard_iface->refcount)) 57 goto out; 58 } 59 60 hard_iface = NULL; 61 62 out: 63 rcu_read_unlock(); 64 return hard_iface; 65 } 66 67 static int is_valid_iface(struct net_device *net_dev) 68 { 69 if (net_dev->flags & IFF_LOOPBACK) 70 return 0; 71 72 if (net_dev->type != ARPHRD_ETHER) 73 return 0; 74 75 if (net_dev->addr_len != ETH_ALEN) 76 return 0; 77 78 /* no batman over batman */ 79 if (softif_is_valid(net_dev)) 80 return 0; 81 82 /* Device is being bridged */ 83 /* if (net_dev->priv_flags & IFF_BRIDGE_PORT) 84 return 0; */ 85 86 return 1; 87 } 88 89 static struct hard_iface *hardif_get_active(struct net_device *soft_iface) 90 { 91 struct hard_iface *hard_iface; 92 93 rcu_read_lock(); 94 list_for_each_entry_rcu(hard_iface, &hardif_list, list) { 95 if (hard_iface->soft_iface != soft_iface) 96 continue; 97 98 if (hard_iface->if_status == IF_ACTIVE && 99 atomic_inc_not_zero(&hard_iface->refcount)) 100 goto out; 101 } 102 103 hard_iface = NULL; 104 105 out: 106 rcu_read_unlock(); 107 return hard_iface; 108 } 109 110 static void primary_if_update_addr(struct bat_priv *bat_priv) 111 { 112 struct vis_packet *vis_packet; 113 struct hard_iface *primary_if; 114 115 primary_if = primary_if_get_selected(bat_priv); 116 if (!primary_if) 117 goto out; 118 119 vis_packet = (struct vis_packet *) 120 bat_priv->my_vis_info->skb_packet->data; 121 memcpy(vis_packet->vis_orig, primary_if->net_dev->dev_addr, ETH_ALEN); 122 memcpy(vis_packet->sender_orig, 123 primary_if->net_dev->dev_addr, ETH_ALEN); 124 125 out: 126 if (primary_if) 127 hardif_free_ref(primary_if); 128 } 129 130 static void primary_if_select(struct bat_priv *bat_priv, 131 struct hard_iface *new_hard_iface) 132 { 133 struct hard_iface *curr_hard_iface; 134 struct batman_packet *batman_packet; 135 136 ASSERT_RTNL(); 137 138 if (new_hard_iface && !atomic_inc_not_zero(&new_hard_iface->refcount)) 139 new_hard_iface = NULL; 140 141 curr_hard_iface = bat_priv->primary_if; 142 rcu_assign_pointer(bat_priv->primary_if, new_hard_iface); 143 144 if (curr_hard_iface) 145 hardif_free_ref(curr_hard_iface); 146 147 if (!new_hard_iface) 148 return; 149 150 batman_packet = (struct batman_packet *)(new_hard_iface->packet_buff); 151 batman_packet->flags = PRIMARIES_FIRST_HOP; 152 batman_packet->ttl = TTL; 153 154 primary_if_update_addr(bat_priv); 155 156 /*** 157 * hacky trick to make sure that we send the TT information via 158 * our new primary interface 159 */ 160 atomic_set(&bat_priv->tt_local_changed, 1); 161 } 162 163 static bool hardif_is_iface_up(struct hard_iface *hard_iface) 164 { 165 if (hard_iface->net_dev->flags & IFF_UP) 166 return true; 167 168 return false; 169 } 170 171 static void update_mac_addresses(struct hard_iface *hard_iface) 172 { 173 memcpy(((struct batman_packet *)(hard_iface->packet_buff))->orig, 174 hard_iface->net_dev->dev_addr, ETH_ALEN); 175 memcpy(((struct batman_packet *)(hard_iface->packet_buff))->prev_sender, 176 hard_iface->net_dev->dev_addr, ETH_ALEN); 177 } 178 179 static void check_known_mac_addr(struct net_device *net_dev) 180 { 181 struct hard_iface *hard_iface; 182 183 rcu_read_lock(); 184 list_for_each_entry_rcu(hard_iface, &hardif_list, list) { 185 if ((hard_iface->if_status != IF_ACTIVE) && 186 (hard_iface->if_status != IF_TO_BE_ACTIVATED)) 187 continue; 188 189 if (hard_iface->net_dev == net_dev) 190 continue; 191 192 if (!compare_eth(hard_iface->net_dev->dev_addr, 193 net_dev->dev_addr)) 194 continue; 195 196 pr_warning("The newly added mac address (%pM) already exists " 197 "on: %s\n", net_dev->dev_addr, 198 hard_iface->net_dev->name); 199 pr_warning("It is strongly recommended to keep mac addresses " 200 "unique to avoid problems!\n"); 201 } 202 rcu_read_unlock(); 203 } 204 205 int hardif_min_mtu(struct net_device *soft_iface) 206 { 207 struct bat_priv *bat_priv = netdev_priv(soft_iface); 208 struct hard_iface *hard_iface; 209 /* allow big frames if all devices are capable to do so 210 * (have MTU > 1500 + BAT_HEADER_LEN) */ 211 int min_mtu = ETH_DATA_LEN; 212 213 if (atomic_read(&bat_priv->fragmentation)) 214 goto out; 215 216 rcu_read_lock(); 217 list_for_each_entry_rcu(hard_iface, &hardif_list, list) { 218 if ((hard_iface->if_status != IF_ACTIVE) && 219 (hard_iface->if_status != IF_TO_BE_ACTIVATED)) 220 continue; 221 222 if (hard_iface->soft_iface != soft_iface) 223 continue; 224 225 min_mtu = min_t(int, hard_iface->net_dev->mtu - BAT_HEADER_LEN, 226 min_mtu); 227 } 228 rcu_read_unlock(); 229 out: 230 return min_mtu; 231 } 232 233 /* adjusts the MTU if a new interface with a smaller MTU appeared. */ 234 void update_min_mtu(struct net_device *soft_iface) 235 { 236 int min_mtu; 237 238 min_mtu = hardif_min_mtu(soft_iface); 239 if (soft_iface->mtu != min_mtu) 240 soft_iface->mtu = min_mtu; 241 } 242 243 static void hardif_activate_interface(struct hard_iface *hard_iface) 244 { 245 struct bat_priv *bat_priv; 246 struct hard_iface *primary_if = NULL; 247 248 if (hard_iface->if_status != IF_INACTIVE) 249 goto out; 250 251 bat_priv = netdev_priv(hard_iface->soft_iface); 252 253 update_mac_addresses(hard_iface); 254 hard_iface->if_status = IF_TO_BE_ACTIVATED; 255 256 /** 257 * the first active interface becomes our primary interface or 258 * the next active interface after the old primay interface was removed 259 */ 260 primary_if = primary_if_get_selected(bat_priv); 261 if (!primary_if) 262 primary_if_select(bat_priv, hard_iface); 263 264 bat_info(hard_iface->soft_iface, "Interface activated: %s\n", 265 hard_iface->net_dev->name); 266 267 update_min_mtu(hard_iface->soft_iface); 268 269 out: 270 if (primary_if) 271 hardif_free_ref(primary_if); 272 } 273 274 static void hardif_deactivate_interface(struct hard_iface *hard_iface) 275 { 276 if ((hard_iface->if_status != IF_ACTIVE) && 277 (hard_iface->if_status != IF_TO_BE_ACTIVATED)) 278 return; 279 280 hard_iface->if_status = IF_INACTIVE; 281 282 bat_info(hard_iface->soft_iface, "Interface deactivated: %s\n", 283 hard_iface->net_dev->name); 284 285 update_min_mtu(hard_iface->soft_iface); 286 } 287 288 int hardif_enable_interface(struct hard_iface *hard_iface, char *iface_name) 289 { 290 struct bat_priv *bat_priv; 291 struct batman_packet *batman_packet; 292 struct net_device *soft_iface; 293 int ret; 294 295 if (hard_iface->if_status != IF_NOT_IN_USE) 296 goto out; 297 298 if (!atomic_inc_not_zero(&hard_iface->refcount)) 299 goto out; 300 301 soft_iface = dev_get_by_name(&init_net, iface_name); 302 303 if (!soft_iface) { 304 soft_iface = softif_create(iface_name); 305 306 if (!soft_iface) { 307 ret = -ENOMEM; 308 goto err; 309 } 310 311 /* dev_get_by_name() increases the reference counter for us */ 312 dev_hold(soft_iface); 313 } 314 315 if (!softif_is_valid(soft_iface)) { 316 pr_err("Can't create batman mesh interface %s: " 317 "already exists as regular interface\n", 318 soft_iface->name); 319 dev_put(soft_iface); 320 ret = -EINVAL; 321 goto err; 322 } 323 324 hard_iface->soft_iface = soft_iface; 325 bat_priv = netdev_priv(hard_iface->soft_iface); 326 hard_iface->packet_len = BAT_PACKET_LEN; 327 hard_iface->packet_buff = kmalloc(hard_iface->packet_len, GFP_ATOMIC); 328 329 if (!hard_iface->packet_buff) { 330 bat_err(hard_iface->soft_iface, "Can't add interface packet " 331 "(%s): out of memory\n", hard_iface->net_dev->name); 332 ret = -ENOMEM; 333 goto err; 334 } 335 336 batman_packet = (struct batman_packet *)(hard_iface->packet_buff); 337 batman_packet->packet_type = BAT_PACKET; 338 batman_packet->version = COMPAT_VERSION; 339 batman_packet->flags = 0; 340 batman_packet->ttl = 2; 341 batman_packet->tq = TQ_MAX_VALUE; 342 batman_packet->num_tt = 0; 343 344 hard_iface->if_num = bat_priv->num_ifaces; 345 bat_priv->num_ifaces++; 346 hard_iface->if_status = IF_INACTIVE; 347 orig_hash_add_if(hard_iface, bat_priv->num_ifaces); 348 349 hard_iface->batman_adv_ptype.type = __constant_htons(ETH_P_BATMAN); 350 hard_iface->batman_adv_ptype.func = batman_skb_recv; 351 hard_iface->batman_adv_ptype.dev = hard_iface->net_dev; 352 dev_add_pack(&hard_iface->batman_adv_ptype); 353 354 atomic_set(&hard_iface->seqno, 1); 355 atomic_set(&hard_iface->frag_seqno, 1); 356 bat_info(hard_iface->soft_iface, "Adding interface: %s\n", 357 hard_iface->net_dev->name); 358 359 if (atomic_read(&bat_priv->fragmentation) && hard_iface->net_dev->mtu < 360 ETH_DATA_LEN + BAT_HEADER_LEN) 361 bat_info(hard_iface->soft_iface, 362 "The MTU of interface %s is too small (%i) to handle " 363 "the transport of batman-adv packets. Packets going " 364 "over this interface will be fragmented on layer2 " 365 "which could impact the performance. Setting the MTU " 366 "to %zi would solve the problem.\n", 367 hard_iface->net_dev->name, hard_iface->net_dev->mtu, 368 ETH_DATA_LEN + BAT_HEADER_LEN); 369 370 if (!atomic_read(&bat_priv->fragmentation) && hard_iface->net_dev->mtu < 371 ETH_DATA_LEN + BAT_HEADER_LEN) 372 bat_info(hard_iface->soft_iface, 373 "The MTU of interface %s is too small (%i) to handle " 374 "the transport of batman-adv packets. If you experience" 375 " problems getting traffic through try increasing the " 376 "MTU to %zi.\n", 377 hard_iface->net_dev->name, hard_iface->net_dev->mtu, 378 ETH_DATA_LEN + BAT_HEADER_LEN); 379 380 if (hardif_is_iface_up(hard_iface)) 381 hardif_activate_interface(hard_iface); 382 else 383 bat_err(hard_iface->soft_iface, "Not using interface %s " 384 "(retrying later): interface not active\n", 385 hard_iface->net_dev->name); 386 387 /* begin scheduling originator messages on that interface */ 388 schedule_own_packet(hard_iface); 389 390 out: 391 return 0; 392 393 err: 394 hardif_free_ref(hard_iface); 395 return ret; 396 } 397 398 void hardif_disable_interface(struct hard_iface *hard_iface) 399 { 400 struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface); 401 struct hard_iface *primary_if = NULL; 402 403 if (hard_iface->if_status == IF_ACTIVE) 404 hardif_deactivate_interface(hard_iface); 405 406 if (hard_iface->if_status != IF_INACTIVE) 407 goto out; 408 409 bat_info(hard_iface->soft_iface, "Removing interface: %s\n", 410 hard_iface->net_dev->name); 411 dev_remove_pack(&hard_iface->batman_adv_ptype); 412 413 bat_priv->num_ifaces--; 414 orig_hash_del_if(hard_iface, bat_priv->num_ifaces); 415 416 primary_if = primary_if_get_selected(bat_priv); 417 if (hard_iface == primary_if) { 418 struct hard_iface *new_if; 419 420 new_if = hardif_get_active(hard_iface->soft_iface); 421 primary_if_select(bat_priv, new_if); 422 423 if (new_if) 424 hardif_free_ref(new_if); 425 } 426 427 kfree(hard_iface->packet_buff); 428 hard_iface->packet_buff = NULL; 429 hard_iface->if_status = IF_NOT_IN_USE; 430 431 /* delete all references to this hard_iface */ 432 purge_orig_ref(bat_priv); 433 purge_outstanding_packets(bat_priv, hard_iface); 434 dev_put(hard_iface->soft_iface); 435 436 /* nobody uses this interface anymore */ 437 if (!bat_priv->num_ifaces) 438 softif_destroy(hard_iface->soft_iface); 439 440 hard_iface->soft_iface = NULL; 441 hardif_free_ref(hard_iface); 442 443 out: 444 if (primary_if) 445 hardif_free_ref(primary_if); 446 } 447 448 static struct hard_iface *hardif_add_interface(struct net_device *net_dev) 449 { 450 struct hard_iface *hard_iface; 451 int ret; 452 453 ASSERT_RTNL(); 454 455 ret = is_valid_iface(net_dev); 456 if (ret != 1) 457 goto out; 458 459 dev_hold(net_dev); 460 461 hard_iface = kmalloc(sizeof(struct hard_iface), GFP_ATOMIC); 462 if (!hard_iface) { 463 pr_err("Can't add interface (%s): out of memory\n", 464 net_dev->name); 465 goto release_dev; 466 } 467 468 ret = sysfs_add_hardif(&hard_iface->hardif_obj, net_dev); 469 if (ret) 470 goto free_if; 471 472 hard_iface->if_num = -1; 473 hard_iface->net_dev = net_dev; 474 hard_iface->soft_iface = NULL; 475 hard_iface->if_status = IF_NOT_IN_USE; 476 INIT_LIST_HEAD(&hard_iface->list); 477 /* extra reference for return */ 478 atomic_set(&hard_iface->refcount, 2); 479 480 check_known_mac_addr(hard_iface->net_dev); 481 list_add_tail_rcu(&hard_iface->list, &hardif_list); 482 483 return hard_iface; 484 485 free_if: 486 kfree(hard_iface); 487 release_dev: 488 dev_put(net_dev); 489 out: 490 return NULL; 491 } 492 493 static void hardif_remove_interface(struct hard_iface *hard_iface) 494 { 495 ASSERT_RTNL(); 496 497 /* first deactivate interface */ 498 if (hard_iface->if_status != IF_NOT_IN_USE) 499 hardif_disable_interface(hard_iface); 500 501 if (hard_iface->if_status != IF_NOT_IN_USE) 502 return; 503 504 hard_iface->if_status = IF_TO_BE_REMOVED; 505 sysfs_del_hardif(&hard_iface->hardif_obj); 506 hardif_free_ref(hard_iface); 507 } 508 509 void hardif_remove_interfaces(void) 510 { 511 struct hard_iface *hard_iface, *hard_iface_tmp; 512 513 rtnl_lock(); 514 list_for_each_entry_safe(hard_iface, hard_iface_tmp, 515 &hardif_list, list) { 516 list_del_rcu(&hard_iface->list); 517 hardif_remove_interface(hard_iface); 518 } 519 rtnl_unlock(); 520 } 521 522 static int hard_if_event(struct notifier_block *this, 523 unsigned long event, void *ptr) 524 { 525 struct net_device *net_dev = (struct net_device *)ptr; 526 struct hard_iface *hard_iface = hardif_get_by_netdev(net_dev); 527 struct hard_iface *primary_if = NULL; 528 struct bat_priv *bat_priv; 529 530 if (!hard_iface && event == NETDEV_REGISTER) 531 hard_iface = hardif_add_interface(net_dev); 532 533 if (!hard_iface) 534 goto out; 535 536 switch (event) { 537 case NETDEV_UP: 538 hardif_activate_interface(hard_iface); 539 break; 540 case NETDEV_GOING_DOWN: 541 case NETDEV_DOWN: 542 hardif_deactivate_interface(hard_iface); 543 break; 544 case NETDEV_UNREGISTER: 545 list_del_rcu(&hard_iface->list); 546 547 hardif_remove_interface(hard_iface); 548 break; 549 case NETDEV_CHANGEMTU: 550 if (hard_iface->soft_iface) 551 update_min_mtu(hard_iface->soft_iface); 552 break; 553 case NETDEV_CHANGEADDR: 554 if (hard_iface->if_status == IF_NOT_IN_USE) 555 goto hardif_put; 556 557 check_known_mac_addr(hard_iface->net_dev); 558 update_mac_addresses(hard_iface); 559 560 bat_priv = netdev_priv(hard_iface->soft_iface); 561 primary_if = primary_if_get_selected(bat_priv); 562 if (!primary_if) 563 goto hardif_put; 564 565 if (hard_iface == primary_if) 566 primary_if_update_addr(bat_priv); 567 break; 568 default: 569 break; 570 }; 571 572 hardif_put: 573 hardif_free_ref(hard_iface); 574 out: 575 if (primary_if) 576 hardif_free_ref(primary_if); 577 return NOTIFY_DONE; 578 } 579 580 /* receive a packet with the batman ethertype coming on a hard 581 * interface */ 582 static int batman_skb_recv(struct sk_buff *skb, struct net_device *dev, 583 struct packet_type *ptype, 584 struct net_device *orig_dev) 585 { 586 struct bat_priv *bat_priv; 587 struct batman_packet *batman_packet; 588 struct hard_iface *hard_iface; 589 int ret; 590 591 hard_iface = container_of(ptype, struct hard_iface, batman_adv_ptype); 592 skb = skb_share_check(skb, GFP_ATOMIC); 593 594 /* skb was released by skb_share_check() */ 595 if (!skb) 596 goto err_out; 597 598 /* packet should hold at least type and version */ 599 if (unlikely(!pskb_may_pull(skb, 2))) 600 goto err_free; 601 602 /* expect a valid ethernet header here. */ 603 if (unlikely(skb->mac_len != sizeof(struct ethhdr) 604 || !skb_mac_header(skb))) 605 goto err_free; 606 607 if (!hard_iface->soft_iface) 608 goto err_free; 609 610 bat_priv = netdev_priv(hard_iface->soft_iface); 611 612 if (atomic_read(&bat_priv->mesh_state) != MESH_ACTIVE) 613 goto err_free; 614 615 /* discard frames on not active interfaces */ 616 if (hard_iface->if_status != IF_ACTIVE) 617 goto err_free; 618 619 batman_packet = (struct batman_packet *)skb->data; 620 621 if (batman_packet->version != COMPAT_VERSION) { 622 bat_dbg(DBG_BATMAN, bat_priv, 623 "Drop packet: incompatible batman version (%i)\n", 624 batman_packet->version); 625 goto err_free; 626 } 627 628 /* all receive handlers return whether they received or reused 629 * the supplied skb. if not, we have to free the skb. */ 630 631 switch (batman_packet->packet_type) { 632 /* batman originator packet */ 633 case BAT_PACKET: 634 ret = recv_bat_packet(skb, hard_iface); 635 break; 636 637 /* batman icmp packet */ 638 case BAT_ICMP: 639 ret = recv_icmp_packet(skb, hard_iface); 640 break; 641 642 /* unicast packet */ 643 case BAT_UNICAST: 644 ret = recv_unicast_packet(skb, hard_iface); 645 break; 646 647 /* fragmented unicast packet */ 648 case BAT_UNICAST_FRAG: 649 ret = recv_ucast_frag_packet(skb, hard_iface); 650 break; 651 652 /* broadcast packet */ 653 case BAT_BCAST: 654 ret = recv_bcast_packet(skb, hard_iface); 655 break; 656 657 /* vis packet */ 658 case BAT_VIS: 659 ret = recv_vis_packet(skb, hard_iface); 660 break; 661 default: 662 ret = NET_RX_DROP; 663 } 664 665 if (ret == NET_RX_DROP) 666 kfree_skb(skb); 667 668 /* return NET_RX_SUCCESS in any case as we 669 * most probably dropped the packet for 670 * routing-logical reasons. */ 671 672 return NET_RX_SUCCESS; 673 674 err_free: 675 kfree_skb(skb); 676 err_out: 677 return NET_RX_DROP; 678 } 679 680 struct notifier_block hard_if_notifier = { 681 .notifier_call = hard_if_event, 682 }; 683