1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (C) B.A.T.M.A.N. contributors: 3 * 4 * Marek Lindner, Simon Wunderlich 5 */ 6 7 #include "hard-interface.h" 8 #include "main.h" 9 10 #include <linux/atomic.h> 11 #include <linux/byteorder/generic.h> 12 #include <linux/gfp.h> 13 #include <linux/if.h> 14 #include <linux/if_arp.h> 15 #include <linux/if_ether.h> 16 #include <linux/kernel.h> 17 #include <linux/kref.h> 18 #include <linux/limits.h> 19 #include <linux/list.h> 20 #include <linux/minmax.h> 21 #include <linux/mutex.h> 22 #include <linux/netdevice.h> 23 #include <linux/printk.h> 24 #include <linux/rculist.h> 25 #include <linux/rtnetlink.h> 26 #include <linux/slab.h> 27 #include <linux/spinlock.h> 28 #include <net/net_namespace.h> 29 #include <net/rtnetlink.h> 30 #include <uapi/linux/batadv_packet.h> 31 32 #include "bat_v.h" 33 #include "bridge_loop_avoidance.h" 34 #include "distributed-arp-table.h" 35 #include "gateway_client.h" 36 #include "log.h" 37 #include "originator.h" 38 #include "send.h" 39 #include "soft-interface.h" 40 #include "translation-table.h" 41 42 /** 43 * batadv_hardif_release() - release hard interface from lists and queue for 44 * free after rcu grace period 45 * @ref: kref pointer of the hard interface 46 */ 47 void batadv_hardif_release(struct kref *ref) 48 { 49 struct batadv_hard_iface *hard_iface; 50 51 hard_iface = container_of(ref, struct batadv_hard_iface, refcount); 52 dev_put(hard_iface->net_dev); 53 54 kfree_rcu(hard_iface, rcu); 55 } 56 57 /** 58 * batadv_hardif_get_by_netdev() - Get hard interface object of a net_device 59 * @net_dev: net_device to search for 60 * 61 * Return: batadv_hard_iface of net_dev (with increased refcnt), NULL on errors 62 */ 63 struct batadv_hard_iface * 64 batadv_hardif_get_by_netdev(const struct net_device *net_dev) 65 { 66 struct batadv_hard_iface *hard_iface; 67 68 rcu_read_lock(); 69 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { 70 if (hard_iface->net_dev == net_dev && 71 kref_get_unless_zero(&hard_iface->refcount)) 72 goto out; 73 } 74 75 hard_iface = NULL; 76 77 out: 78 rcu_read_unlock(); 79 return hard_iface; 80 } 81 82 /** 83 * batadv_getlink_net() - return link net namespace (of use fallback) 84 * @netdev: net_device to check 85 * @fallback_net: return in case get_link_net is not available for @netdev 86 * 87 * Return: result of rtnl_link_ops->get_link_net or @fallback_net 88 */ 89 static struct net *batadv_getlink_net(const struct net_device *netdev, 90 struct net *fallback_net) 91 { 92 if (!netdev->rtnl_link_ops) 93 return fallback_net; 94 95 if (!netdev->rtnl_link_ops->get_link_net) 96 return fallback_net; 97 98 return netdev->rtnl_link_ops->get_link_net(netdev); 99 } 100 101 /** 102 * batadv_mutual_parents() - check if two devices are each others parent 103 * @dev1: 1st net dev 104 * @net1: 1st devices netns 105 * @dev2: 2nd net dev 106 * @net2: 2nd devices netns 107 * 108 * veth devices come in pairs and each is the parent of the other! 109 * 110 * Return: true if the devices are each others parent, otherwise false 111 */ 112 static bool batadv_mutual_parents(const struct net_device *dev1, 113 struct net *net1, 114 const struct net_device *dev2, 115 struct net *net2) 116 { 117 int dev1_parent_iflink = dev_get_iflink(dev1); 118 int dev2_parent_iflink = dev_get_iflink(dev2); 119 const struct net *dev1_parent_net; 120 const struct net *dev2_parent_net; 121 122 dev1_parent_net = batadv_getlink_net(dev1, net1); 123 dev2_parent_net = batadv_getlink_net(dev2, net2); 124 125 if (!dev1_parent_iflink || !dev2_parent_iflink) 126 return false; 127 128 return (dev1_parent_iflink == dev2->ifindex) && 129 (dev2_parent_iflink == dev1->ifindex) && 130 net_eq(dev1_parent_net, net2) && 131 net_eq(dev2_parent_net, net1); 132 } 133 134 /** 135 * batadv_is_on_batman_iface() - check if a device is a batman iface descendant 136 * @net_dev: the device to check 137 * 138 * If the user creates any virtual device on top of a batman-adv interface, it 139 * is important to prevent this new interface from being used to create a new 140 * mesh network (this behaviour would lead to a batman-over-batman 141 * configuration). This function recursively checks all the fathers of the 142 * device passed as argument looking for a batman-adv soft interface. 143 * 144 * Return: true if the device is descendant of a batman-adv mesh interface (or 145 * if it is a batman-adv interface itself), false otherwise 146 */ 147 static bool batadv_is_on_batman_iface(const struct net_device *net_dev) 148 { 149 struct net *net = dev_net(net_dev); 150 struct net_device *parent_dev; 151 struct net *parent_net; 152 int iflink; 153 bool ret; 154 155 /* check if this is a batman-adv mesh interface */ 156 if (batadv_softif_is_valid(net_dev)) 157 return true; 158 159 iflink = dev_get_iflink(net_dev); 160 if (iflink == 0) 161 return false; 162 163 parent_net = batadv_getlink_net(net_dev, net); 164 165 /* iflink to itself, most likely physical device */ 166 if (net == parent_net && iflink == net_dev->ifindex) 167 return false; 168 169 /* recurse over the parent device */ 170 parent_dev = __dev_get_by_index((struct net *)parent_net, iflink); 171 /* if we got a NULL parent_dev there is something broken.. */ 172 if (!parent_dev) { 173 pr_err("Cannot find parent device\n"); 174 return false; 175 } 176 177 if (batadv_mutual_parents(net_dev, net, parent_dev, parent_net)) 178 return false; 179 180 ret = batadv_is_on_batman_iface(parent_dev); 181 182 return ret; 183 } 184 185 static bool batadv_is_valid_iface(const struct net_device *net_dev) 186 { 187 if (net_dev->flags & IFF_LOOPBACK) 188 return false; 189 190 if (net_dev->type != ARPHRD_ETHER) 191 return false; 192 193 if (net_dev->addr_len != ETH_ALEN) 194 return false; 195 196 /* no batman over batman */ 197 if (batadv_is_on_batman_iface(net_dev)) 198 return false; 199 200 return true; 201 } 202 203 /** 204 * batadv_get_real_netdevice() - check if the given netdev struct is a virtual 205 * interface on top of another 'real' interface 206 * @netdev: the device to check 207 * 208 * Callers must hold the rtnl semaphore. You may want batadv_get_real_netdev() 209 * instead of this. 210 * 211 * Return: the 'real' net device or the original net device and NULL in case 212 * of an error. 213 */ 214 static struct net_device *batadv_get_real_netdevice(struct net_device *netdev) 215 { 216 struct batadv_hard_iface *hard_iface = NULL; 217 struct net_device *real_netdev = NULL; 218 struct net *real_net; 219 struct net *net; 220 int iflink; 221 222 ASSERT_RTNL(); 223 224 if (!netdev) 225 return NULL; 226 227 iflink = dev_get_iflink(netdev); 228 if (iflink == 0) { 229 dev_hold(netdev); 230 return netdev; 231 } 232 233 hard_iface = batadv_hardif_get_by_netdev(netdev); 234 if (!hard_iface || !hard_iface->soft_iface) 235 goto out; 236 237 net = dev_net(hard_iface->soft_iface); 238 real_net = batadv_getlink_net(netdev, net); 239 240 /* iflink to itself, most likely physical device */ 241 if (net == real_net && netdev->ifindex == iflink) { 242 real_netdev = netdev; 243 dev_hold(real_netdev); 244 goto out; 245 } 246 247 real_netdev = dev_get_by_index(real_net, iflink); 248 249 out: 250 batadv_hardif_put(hard_iface); 251 return real_netdev; 252 } 253 254 /** 255 * batadv_get_real_netdev() - check if the given net_device struct is a virtual 256 * interface on top of another 'real' interface 257 * @net_device: the device to check 258 * 259 * Return: the 'real' net device or the original net device and NULL in case 260 * of an error. 261 */ 262 struct net_device *batadv_get_real_netdev(struct net_device *net_device) 263 { 264 struct net_device *real_netdev; 265 266 rtnl_lock(); 267 real_netdev = batadv_get_real_netdevice(net_device); 268 rtnl_unlock(); 269 270 return real_netdev; 271 } 272 273 /** 274 * batadv_is_wext_netdev() - check if the given net_device struct is a 275 * wext wifi interface 276 * @net_device: the device to check 277 * 278 * Return: true if the net device is a wext wireless device, false 279 * otherwise. 280 */ 281 static bool batadv_is_wext_netdev(struct net_device *net_device) 282 { 283 if (!net_device) 284 return false; 285 286 #ifdef CONFIG_WIRELESS_EXT 287 /* pre-cfg80211 drivers have to implement WEXT, so it is possible to 288 * check for wireless_handlers != NULL 289 */ 290 if (net_device->wireless_handlers) 291 return true; 292 #endif 293 294 return false; 295 } 296 297 /** 298 * batadv_is_cfg80211_netdev() - check if the given net_device struct is a 299 * cfg80211 wifi interface 300 * @net_device: the device to check 301 * 302 * Return: true if the net device is a cfg80211 wireless device, false 303 * otherwise. 304 */ 305 static bool batadv_is_cfg80211_netdev(struct net_device *net_device) 306 { 307 if (!net_device) 308 return false; 309 310 /* cfg80211 drivers have to set ieee80211_ptr */ 311 if (net_device->ieee80211_ptr) 312 return true; 313 314 return false; 315 } 316 317 /** 318 * batadv_wifi_flags_evaluate() - calculate wifi flags for net_device 319 * @net_device: the device to check 320 * 321 * Return: batadv_hard_iface_wifi_flags flags of the device 322 */ 323 static u32 batadv_wifi_flags_evaluate(struct net_device *net_device) 324 { 325 u32 wifi_flags = 0; 326 struct net_device *real_netdev; 327 328 if (batadv_is_wext_netdev(net_device)) 329 wifi_flags |= BATADV_HARDIF_WIFI_WEXT_DIRECT; 330 331 if (batadv_is_cfg80211_netdev(net_device)) 332 wifi_flags |= BATADV_HARDIF_WIFI_CFG80211_DIRECT; 333 334 real_netdev = batadv_get_real_netdevice(net_device); 335 if (!real_netdev) 336 return wifi_flags; 337 338 if (real_netdev == net_device) 339 goto out; 340 341 if (batadv_is_wext_netdev(real_netdev)) 342 wifi_flags |= BATADV_HARDIF_WIFI_WEXT_INDIRECT; 343 344 if (batadv_is_cfg80211_netdev(real_netdev)) 345 wifi_flags |= BATADV_HARDIF_WIFI_CFG80211_INDIRECT; 346 347 out: 348 dev_put(real_netdev); 349 return wifi_flags; 350 } 351 352 /** 353 * batadv_is_cfg80211_hardif() - check if the given hardif is a cfg80211 wifi 354 * interface 355 * @hard_iface: the device to check 356 * 357 * Return: true if the net device is a cfg80211 wireless device, false 358 * otherwise. 359 */ 360 bool batadv_is_cfg80211_hardif(struct batadv_hard_iface *hard_iface) 361 { 362 u32 allowed_flags = 0; 363 364 allowed_flags |= BATADV_HARDIF_WIFI_CFG80211_DIRECT; 365 allowed_flags |= BATADV_HARDIF_WIFI_CFG80211_INDIRECT; 366 367 return !!(hard_iface->wifi_flags & allowed_flags); 368 } 369 370 /** 371 * batadv_is_wifi_hardif() - check if the given hardif is a wifi interface 372 * @hard_iface: the device to check 373 * 374 * Return: true if the net device is a 802.11 wireless device, false otherwise. 375 */ 376 bool batadv_is_wifi_hardif(struct batadv_hard_iface *hard_iface) 377 { 378 if (!hard_iface) 379 return false; 380 381 return hard_iface->wifi_flags != 0; 382 } 383 384 /** 385 * batadv_hardif_no_broadcast() - check whether (re)broadcast is necessary 386 * @if_outgoing: the outgoing interface checked and considered for (re)broadcast 387 * @orig_addr: the originator of this packet 388 * @orig_neigh: originator address of the forwarder we just got the packet from 389 * (NULL if we originated) 390 * 391 * Checks whether a packet needs to be (re)broadcasted on the given interface. 392 * 393 * Return: 394 * BATADV_HARDIF_BCAST_NORECIPIENT: No neighbor on interface 395 * BATADV_HARDIF_BCAST_DUPFWD: Just one neighbor, but it is the forwarder 396 * BATADV_HARDIF_BCAST_DUPORIG: Just one neighbor, but it is the originator 397 * BATADV_HARDIF_BCAST_OK: Several neighbors, must broadcast 398 */ 399 int batadv_hardif_no_broadcast(struct batadv_hard_iface *if_outgoing, 400 u8 *orig_addr, u8 *orig_neigh) 401 { 402 struct batadv_hardif_neigh_node *hardif_neigh; 403 struct hlist_node *first; 404 int ret = BATADV_HARDIF_BCAST_OK; 405 406 rcu_read_lock(); 407 408 /* 0 neighbors -> no (re)broadcast */ 409 first = rcu_dereference(hlist_first_rcu(&if_outgoing->neigh_list)); 410 if (!first) { 411 ret = BATADV_HARDIF_BCAST_NORECIPIENT; 412 goto out; 413 } 414 415 /* >1 neighbors -> (re)broadcast */ 416 if (rcu_dereference(hlist_next_rcu(first))) 417 goto out; 418 419 hardif_neigh = hlist_entry(first, struct batadv_hardif_neigh_node, 420 list); 421 422 /* 1 neighbor, is the originator -> no rebroadcast */ 423 if (orig_addr && batadv_compare_eth(hardif_neigh->orig, orig_addr)) { 424 ret = BATADV_HARDIF_BCAST_DUPORIG; 425 /* 1 neighbor, is the one we received from -> no rebroadcast */ 426 } else if (orig_neigh && 427 batadv_compare_eth(hardif_neigh->orig, orig_neigh)) { 428 ret = BATADV_HARDIF_BCAST_DUPFWD; 429 } 430 431 out: 432 rcu_read_unlock(); 433 return ret; 434 } 435 436 static struct batadv_hard_iface * 437 batadv_hardif_get_active(const struct net_device *soft_iface) 438 { 439 struct batadv_hard_iface *hard_iface; 440 441 rcu_read_lock(); 442 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { 443 if (hard_iface->soft_iface != soft_iface) 444 continue; 445 446 if (hard_iface->if_status == BATADV_IF_ACTIVE && 447 kref_get_unless_zero(&hard_iface->refcount)) 448 goto out; 449 } 450 451 hard_iface = NULL; 452 453 out: 454 rcu_read_unlock(); 455 return hard_iface; 456 } 457 458 static void batadv_primary_if_update_addr(struct batadv_priv *bat_priv, 459 struct batadv_hard_iface *oldif) 460 { 461 struct batadv_hard_iface *primary_if; 462 463 primary_if = batadv_primary_if_get_selected(bat_priv); 464 if (!primary_if) 465 goto out; 466 467 batadv_dat_init_own_addr(bat_priv, primary_if); 468 batadv_bla_update_orig_address(bat_priv, primary_if, oldif); 469 out: 470 batadv_hardif_put(primary_if); 471 } 472 473 static void batadv_primary_if_select(struct batadv_priv *bat_priv, 474 struct batadv_hard_iface *new_hard_iface) 475 { 476 struct batadv_hard_iface *curr_hard_iface; 477 478 ASSERT_RTNL(); 479 480 if (new_hard_iface) 481 kref_get(&new_hard_iface->refcount); 482 483 curr_hard_iface = rcu_replace_pointer(bat_priv->primary_if, 484 new_hard_iface, 1); 485 486 if (!new_hard_iface) 487 goto out; 488 489 bat_priv->algo_ops->iface.primary_set(new_hard_iface); 490 batadv_primary_if_update_addr(bat_priv, curr_hard_iface); 491 492 out: 493 batadv_hardif_put(curr_hard_iface); 494 } 495 496 static bool 497 batadv_hardif_is_iface_up(const struct batadv_hard_iface *hard_iface) 498 { 499 if (hard_iface->net_dev->flags & IFF_UP) 500 return true; 501 502 return false; 503 } 504 505 static void batadv_check_known_mac_addr(const struct net_device *net_dev) 506 { 507 const struct batadv_hard_iface *hard_iface; 508 509 rcu_read_lock(); 510 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { 511 if (hard_iface->if_status != BATADV_IF_ACTIVE && 512 hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED) 513 continue; 514 515 if (hard_iface->net_dev == net_dev) 516 continue; 517 518 if (!batadv_compare_eth(hard_iface->net_dev->dev_addr, 519 net_dev->dev_addr)) 520 continue; 521 522 pr_warn("The newly added mac address (%pM) already exists on: %s\n", 523 net_dev->dev_addr, hard_iface->net_dev->name); 524 pr_warn("It is strongly recommended to keep mac addresses unique to avoid problems!\n"); 525 } 526 rcu_read_unlock(); 527 } 528 529 /** 530 * batadv_hardif_recalc_extra_skbroom() - Recalculate skbuff extra head/tailroom 531 * @soft_iface: netdev struct of the mesh interface 532 */ 533 static void batadv_hardif_recalc_extra_skbroom(struct net_device *soft_iface) 534 { 535 const struct batadv_hard_iface *hard_iface; 536 unsigned short lower_header_len = ETH_HLEN; 537 unsigned short lower_headroom = 0; 538 unsigned short lower_tailroom = 0; 539 unsigned short needed_headroom; 540 541 rcu_read_lock(); 542 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { 543 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE) 544 continue; 545 546 if (hard_iface->soft_iface != soft_iface) 547 continue; 548 549 lower_header_len = max_t(unsigned short, lower_header_len, 550 hard_iface->net_dev->hard_header_len); 551 552 lower_headroom = max_t(unsigned short, lower_headroom, 553 hard_iface->net_dev->needed_headroom); 554 555 lower_tailroom = max_t(unsigned short, lower_tailroom, 556 hard_iface->net_dev->needed_tailroom); 557 } 558 rcu_read_unlock(); 559 560 needed_headroom = lower_headroom + (lower_header_len - ETH_HLEN); 561 needed_headroom += batadv_max_header_len(); 562 563 /* fragmentation headers don't strip the unicast/... header */ 564 needed_headroom += sizeof(struct batadv_frag_packet); 565 566 soft_iface->needed_headroom = needed_headroom; 567 soft_iface->needed_tailroom = lower_tailroom; 568 } 569 570 /** 571 * batadv_hardif_min_mtu() - Calculate maximum MTU for soft interface 572 * @soft_iface: netdev struct of the soft interface 573 * 574 * Return: MTU for the soft-interface (limited by the minimal MTU of all active 575 * slave interfaces) 576 */ 577 int batadv_hardif_min_mtu(struct net_device *soft_iface) 578 { 579 struct batadv_priv *bat_priv = netdev_priv(soft_iface); 580 const struct batadv_hard_iface *hard_iface; 581 int min_mtu = INT_MAX; 582 583 rcu_read_lock(); 584 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { 585 if (hard_iface->if_status != BATADV_IF_ACTIVE && 586 hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED) 587 continue; 588 589 if (hard_iface->soft_iface != soft_iface) 590 continue; 591 592 min_mtu = min_t(int, hard_iface->net_dev->mtu, min_mtu); 593 } 594 rcu_read_unlock(); 595 596 if (atomic_read(&bat_priv->fragmentation) == 0) 597 goto out; 598 599 /* with fragmentation enabled the maximum size of internally generated 600 * packets such as translation table exchanges or tvlv containers, etc 601 * has to be calculated 602 */ 603 min_mtu = min_t(int, min_mtu, BATADV_FRAG_MAX_FRAG_SIZE); 604 min_mtu -= sizeof(struct batadv_frag_packet); 605 min_mtu *= BATADV_FRAG_MAX_FRAGMENTS; 606 607 out: 608 /* report to the other components the maximum amount of bytes that 609 * batman-adv can send over the wire (without considering the payload 610 * overhead). For example, this value is used by TT to compute the 611 * maximum local table size 612 */ 613 atomic_set(&bat_priv->packet_size_max, min_mtu); 614 615 /* the real soft-interface MTU is computed by removing the payload 616 * overhead from the maximum amount of bytes that was just computed. 617 * 618 * However batman-adv does not support MTUs bigger than ETH_DATA_LEN 619 */ 620 return min_t(int, min_mtu - batadv_max_header_len(), ETH_DATA_LEN); 621 } 622 623 /** 624 * batadv_update_min_mtu() - Adjusts the MTU if a new interface with a smaller 625 * MTU appeared 626 * @soft_iface: netdev struct of the soft interface 627 */ 628 void batadv_update_min_mtu(struct net_device *soft_iface) 629 { 630 soft_iface->mtu = batadv_hardif_min_mtu(soft_iface); 631 632 /* Check if the local translate table should be cleaned up to match a 633 * new (and smaller) MTU. 634 */ 635 batadv_tt_local_resize_to_mtu(soft_iface); 636 } 637 638 static void 639 batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface) 640 { 641 struct batadv_priv *bat_priv; 642 struct batadv_hard_iface *primary_if = NULL; 643 644 if (hard_iface->if_status != BATADV_IF_INACTIVE) 645 goto out; 646 647 bat_priv = netdev_priv(hard_iface->soft_iface); 648 649 bat_priv->algo_ops->iface.update_mac(hard_iface); 650 hard_iface->if_status = BATADV_IF_TO_BE_ACTIVATED; 651 652 /* the first active interface becomes our primary interface or 653 * the next active interface after the old primary interface was removed 654 */ 655 primary_if = batadv_primary_if_get_selected(bat_priv); 656 if (!primary_if) 657 batadv_primary_if_select(bat_priv, hard_iface); 658 659 batadv_info(hard_iface->soft_iface, "Interface activated: %s\n", 660 hard_iface->net_dev->name); 661 662 batadv_update_min_mtu(hard_iface->soft_iface); 663 664 if (bat_priv->algo_ops->iface.activate) 665 bat_priv->algo_ops->iface.activate(hard_iface); 666 667 out: 668 batadv_hardif_put(primary_if); 669 } 670 671 static void 672 batadv_hardif_deactivate_interface(struct batadv_hard_iface *hard_iface) 673 { 674 if (hard_iface->if_status != BATADV_IF_ACTIVE && 675 hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED) 676 return; 677 678 hard_iface->if_status = BATADV_IF_INACTIVE; 679 680 batadv_info(hard_iface->soft_iface, "Interface deactivated: %s\n", 681 hard_iface->net_dev->name); 682 683 batadv_update_min_mtu(hard_iface->soft_iface); 684 } 685 686 /** 687 * batadv_hardif_enable_interface() - Enslave hard interface to soft interface 688 * @hard_iface: hard interface to add to soft interface 689 * @soft_iface: netdev struct of the mesh interface 690 * 691 * Return: 0 on success or negative error number in case of failure 692 */ 693 int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface, 694 struct net_device *soft_iface) 695 { 696 struct batadv_priv *bat_priv; 697 __be16 ethertype = htons(ETH_P_BATMAN); 698 int max_header_len = batadv_max_header_len(); 699 int ret; 700 701 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE) 702 goto out; 703 704 kref_get(&hard_iface->refcount); 705 706 dev_hold(soft_iface); 707 hard_iface->soft_iface = soft_iface; 708 bat_priv = netdev_priv(hard_iface->soft_iface); 709 710 ret = netdev_master_upper_dev_link(hard_iface->net_dev, 711 soft_iface, NULL, NULL, NULL); 712 if (ret) 713 goto err_dev; 714 715 ret = bat_priv->algo_ops->iface.enable(hard_iface); 716 if (ret < 0) 717 goto err_upper; 718 719 hard_iface->if_status = BATADV_IF_INACTIVE; 720 721 kref_get(&hard_iface->refcount); 722 hard_iface->batman_adv_ptype.type = ethertype; 723 hard_iface->batman_adv_ptype.func = batadv_batman_skb_recv; 724 hard_iface->batman_adv_ptype.dev = hard_iface->net_dev; 725 dev_add_pack(&hard_iface->batman_adv_ptype); 726 727 batadv_info(hard_iface->soft_iface, "Adding interface: %s\n", 728 hard_iface->net_dev->name); 729 730 if (atomic_read(&bat_priv->fragmentation) && 731 hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len) 732 batadv_info(hard_iface->soft_iface, 733 "The MTU of interface %s is too small (%i) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to %i would solve the problem.\n", 734 hard_iface->net_dev->name, hard_iface->net_dev->mtu, 735 ETH_DATA_LEN + max_header_len); 736 737 if (!atomic_read(&bat_priv->fragmentation) && 738 hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len) 739 batadv_info(hard_iface->soft_iface, 740 "The MTU of interface %s is too small (%i) to handle the transport of batman-adv packets. If you experience problems getting traffic through try increasing the MTU to %i.\n", 741 hard_iface->net_dev->name, hard_iface->net_dev->mtu, 742 ETH_DATA_LEN + max_header_len); 743 744 if (batadv_hardif_is_iface_up(hard_iface)) 745 batadv_hardif_activate_interface(hard_iface); 746 else 747 batadv_err(hard_iface->soft_iface, 748 "Not using interface %s (retrying later): interface not active\n", 749 hard_iface->net_dev->name); 750 751 batadv_hardif_recalc_extra_skbroom(soft_iface); 752 753 if (bat_priv->algo_ops->iface.enabled) 754 bat_priv->algo_ops->iface.enabled(hard_iface); 755 756 out: 757 return 0; 758 759 err_upper: 760 netdev_upper_dev_unlink(hard_iface->net_dev, soft_iface); 761 err_dev: 762 hard_iface->soft_iface = NULL; 763 dev_put(soft_iface); 764 batadv_hardif_put(hard_iface); 765 return ret; 766 } 767 768 /** 769 * batadv_hardif_cnt() - get number of interfaces enslaved to soft interface 770 * @soft_iface: soft interface to check 771 * 772 * This function is only using RCU for locking - the result can therefore be 773 * off when another function is modifying the list at the same time. The 774 * caller can use the rtnl_lock to make sure that the count is accurate. 775 * 776 * Return: number of connected/enslaved hard interfaces 777 */ 778 static size_t batadv_hardif_cnt(const struct net_device *soft_iface) 779 { 780 struct batadv_hard_iface *hard_iface; 781 size_t count = 0; 782 783 rcu_read_lock(); 784 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { 785 if (hard_iface->soft_iface != soft_iface) 786 continue; 787 788 count++; 789 } 790 rcu_read_unlock(); 791 792 return count; 793 } 794 795 /** 796 * batadv_hardif_disable_interface() - Remove hard interface from soft interface 797 * @hard_iface: hard interface to be removed 798 */ 799 void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface) 800 { 801 struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface); 802 struct batadv_hard_iface *primary_if = NULL; 803 804 batadv_hardif_deactivate_interface(hard_iface); 805 806 if (hard_iface->if_status != BATADV_IF_INACTIVE) 807 goto out; 808 809 batadv_info(hard_iface->soft_iface, "Removing interface: %s\n", 810 hard_iface->net_dev->name); 811 dev_remove_pack(&hard_iface->batman_adv_ptype); 812 batadv_hardif_put(hard_iface); 813 814 primary_if = batadv_primary_if_get_selected(bat_priv); 815 if (hard_iface == primary_if) { 816 struct batadv_hard_iface *new_if; 817 818 new_if = batadv_hardif_get_active(hard_iface->soft_iface); 819 batadv_primary_if_select(bat_priv, new_if); 820 821 batadv_hardif_put(new_if); 822 } 823 824 bat_priv->algo_ops->iface.disable(hard_iface); 825 hard_iface->if_status = BATADV_IF_NOT_IN_USE; 826 827 /* delete all references to this hard_iface */ 828 batadv_purge_orig_ref(bat_priv); 829 batadv_purge_outstanding_packets(bat_priv, hard_iface); 830 dev_put(hard_iface->soft_iface); 831 832 netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface); 833 batadv_hardif_recalc_extra_skbroom(hard_iface->soft_iface); 834 835 /* nobody uses this interface anymore */ 836 if (batadv_hardif_cnt(hard_iface->soft_iface) <= 1) 837 batadv_gw_check_client_stop(bat_priv); 838 839 hard_iface->soft_iface = NULL; 840 batadv_hardif_put(hard_iface); 841 842 out: 843 batadv_hardif_put(primary_if); 844 } 845 846 static struct batadv_hard_iface * 847 batadv_hardif_add_interface(struct net_device *net_dev) 848 { 849 struct batadv_hard_iface *hard_iface; 850 851 ASSERT_RTNL(); 852 853 if (!batadv_is_valid_iface(net_dev)) 854 goto out; 855 856 dev_hold(net_dev); 857 858 hard_iface = kzalloc(sizeof(*hard_iface), GFP_ATOMIC); 859 if (!hard_iface) 860 goto release_dev; 861 862 hard_iface->net_dev = net_dev; 863 hard_iface->soft_iface = NULL; 864 hard_iface->if_status = BATADV_IF_NOT_IN_USE; 865 866 INIT_LIST_HEAD(&hard_iface->list); 867 INIT_HLIST_HEAD(&hard_iface->neigh_list); 868 869 mutex_init(&hard_iface->bat_iv.ogm_buff_mutex); 870 spin_lock_init(&hard_iface->neigh_list_lock); 871 kref_init(&hard_iface->refcount); 872 873 hard_iface->num_bcasts = BATADV_NUM_BCASTS_DEFAULT; 874 hard_iface->wifi_flags = batadv_wifi_flags_evaluate(net_dev); 875 if (batadv_is_wifi_hardif(hard_iface)) 876 hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS; 877 878 atomic_set(&hard_iface->hop_penalty, 0); 879 880 batadv_v_hardif_init(hard_iface); 881 882 batadv_check_known_mac_addr(hard_iface->net_dev); 883 kref_get(&hard_iface->refcount); 884 list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list); 885 batadv_hardif_generation++; 886 887 return hard_iface; 888 889 release_dev: 890 dev_put(net_dev); 891 out: 892 return NULL; 893 } 894 895 static void batadv_hardif_remove_interface(struct batadv_hard_iface *hard_iface) 896 { 897 ASSERT_RTNL(); 898 899 /* first deactivate interface */ 900 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE) 901 batadv_hardif_disable_interface(hard_iface); 902 903 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE) 904 return; 905 906 hard_iface->if_status = BATADV_IF_TO_BE_REMOVED; 907 batadv_hardif_put(hard_iface); 908 } 909 910 /** 911 * batadv_hard_if_event_softif() - Handle events for soft interfaces 912 * @event: NETDEV_* event to handle 913 * @net_dev: net_device which generated an event 914 * 915 * Return: NOTIFY_* result 916 */ 917 static int batadv_hard_if_event_softif(unsigned long event, 918 struct net_device *net_dev) 919 { 920 struct batadv_priv *bat_priv; 921 922 switch (event) { 923 case NETDEV_REGISTER: 924 bat_priv = netdev_priv(net_dev); 925 batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS); 926 break; 927 } 928 929 return NOTIFY_DONE; 930 } 931 932 static int batadv_hard_if_event(struct notifier_block *this, 933 unsigned long event, void *ptr) 934 { 935 struct net_device *net_dev = netdev_notifier_info_to_dev(ptr); 936 struct batadv_hard_iface *hard_iface; 937 struct batadv_hard_iface *primary_if = NULL; 938 struct batadv_priv *bat_priv; 939 940 if (batadv_softif_is_valid(net_dev)) 941 return batadv_hard_if_event_softif(event, net_dev); 942 943 hard_iface = batadv_hardif_get_by_netdev(net_dev); 944 if (!hard_iface && (event == NETDEV_REGISTER || 945 event == NETDEV_POST_TYPE_CHANGE)) 946 hard_iface = batadv_hardif_add_interface(net_dev); 947 948 if (!hard_iface) 949 goto out; 950 951 switch (event) { 952 case NETDEV_UP: 953 batadv_hardif_activate_interface(hard_iface); 954 break; 955 case NETDEV_GOING_DOWN: 956 case NETDEV_DOWN: 957 batadv_hardif_deactivate_interface(hard_iface); 958 break; 959 case NETDEV_UNREGISTER: 960 case NETDEV_PRE_TYPE_CHANGE: 961 list_del_rcu(&hard_iface->list); 962 batadv_hardif_generation++; 963 964 batadv_hardif_remove_interface(hard_iface); 965 break; 966 case NETDEV_CHANGEMTU: 967 if (hard_iface->soft_iface) 968 batadv_update_min_mtu(hard_iface->soft_iface); 969 break; 970 case NETDEV_CHANGEADDR: 971 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE) 972 goto hardif_put; 973 974 batadv_check_known_mac_addr(hard_iface->net_dev); 975 976 bat_priv = netdev_priv(hard_iface->soft_iface); 977 bat_priv->algo_ops->iface.update_mac(hard_iface); 978 979 primary_if = batadv_primary_if_get_selected(bat_priv); 980 if (!primary_if) 981 goto hardif_put; 982 983 if (hard_iface == primary_if) 984 batadv_primary_if_update_addr(bat_priv, NULL); 985 break; 986 case NETDEV_CHANGEUPPER: 987 hard_iface->wifi_flags = batadv_wifi_flags_evaluate(net_dev); 988 if (batadv_is_wifi_hardif(hard_iface)) 989 hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS; 990 break; 991 default: 992 break; 993 } 994 995 hardif_put: 996 batadv_hardif_put(hard_iface); 997 out: 998 batadv_hardif_put(primary_if); 999 return NOTIFY_DONE; 1000 } 1001 1002 struct notifier_block batadv_hard_if_notifier = { 1003 .notifier_call = batadv_hard_if_event, 1004 }; 1005