1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (C) 2007-2020 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/errno.h> 13 #include <linux/gfp.h> 14 #include <linux/if.h> 15 #include <linux/if_arp.h> 16 #include <linux/if_ether.h> 17 #include <linux/kernel.h> 18 #include <linux/kref.h> 19 #include <linux/limits.h> 20 #include <linux/list.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 "debugfs.h" 35 #include "distributed-arp-table.h" 36 #include "gateway_client.h" 37 #include "log.h" 38 #include "originator.h" 39 #include "send.h" 40 #include "soft-interface.h" 41 #include "sysfs.h" 42 #include "translation-table.h" 43 44 /** 45 * batadv_hardif_release() - release hard interface from lists and queue for 46 * free after rcu grace period 47 * @ref: kref pointer of the hard interface 48 */ 49 void batadv_hardif_release(struct kref *ref) 50 { 51 struct batadv_hard_iface *hard_iface; 52 53 hard_iface = container_of(ref, struct batadv_hard_iface, refcount); 54 dev_put(hard_iface->net_dev); 55 56 kfree_rcu(hard_iface, rcu); 57 } 58 59 /** 60 * batadv_hardif_get_by_netdev() - Get hard interface object of a net_device 61 * @net_dev: net_device to search for 62 * 63 * Return: batadv_hard_iface of net_dev (with increased refcnt), NULL on errors 64 */ 65 struct batadv_hard_iface * 66 batadv_hardif_get_by_netdev(const struct net_device *net_dev) 67 { 68 struct batadv_hard_iface *hard_iface; 69 70 rcu_read_lock(); 71 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { 72 if (hard_iface->net_dev == net_dev && 73 kref_get_unless_zero(&hard_iface->refcount)) 74 goto out; 75 } 76 77 hard_iface = NULL; 78 79 out: 80 rcu_read_unlock(); 81 return hard_iface; 82 } 83 84 /** 85 * batadv_getlink_net() - return link net namespace (of use fallback) 86 * @netdev: net_device to check 87 * @fallback_net: return in case get_link_net is not available for @netdev 88 * 89 * Return: result of rtnl_link_ops->get_link_net or @fallback_net 90 */ 91 static struct net *batadv_getlink_net(const struct net_device *netdev, 92 struct net *fallback_net) 93 { 94 if (!netdev->rtnl_link_ops) 95 return fallback_net; 96 97 if (!netdev->rtnl_link_ops->get_link_net) 98 return fallback_net; 99 100 return netdev->rtnl_link_ops->get_link_net(netdev); 101 } 102 103 /** 104 * batadv_mutual_parents() - check if two devices are each others parent 105 * @dev1: 1st net dev 106 * @net1: 1st devices netns 107 * @dev2: 2nd net dev 108 * @net2: 2nd devices netns 109 * 110 * veth devices come in pairs and each is the parent of the other! 111 * 112 * Return: true if the devices are each others parent, otherwise false 113 */ 114 static bool batadv_mutual_parents(const struct net_device *dev1, 115 struct net *net1, 116 const struct net_device *dev2, 117 struct net *net2) 118 { 119 int dev1_parent_iflink = dev_get_iflink(dev1); 120 int dev2_parent_iflink = dev_get_iflink(dev2); 121 const struct net *dev1_parent_net; 122 const struct net *dev2_parent_net; 123 124 dev1_parent_net = batadv_getlink_net(dev1, net1); 125 dev2_parent_net = batadv_getlink_net(dev2, net2); 126 127 if (!dev1_parent_iflink || !dev2_parent_iflink) 128 return false; 129 130 return (dev1_parent_iflink == dev2->ifindex) && 131 (dev2_parent_iflink == dev1->ifindex) && 132 net_eq(dev1_parent_net, net2) && 133 net_eq(dev2_parent_net, net1); 134 } 135 136 /** 137 * batadv_is_on_batman_iface() - check if a device is a batman iface descendant 138 * @net_dev: the device to check 139 * 140 * If the user creates any virtual device on top of a batman-adv interface, it 141 * is important to prevent this new interface to be used to create a new mesh 142 * network (this behaviour would lead to a batman-over-batman configuration). 143 * This function recursively checks all the fathers of the device passed as 144 * argument looking for a batman-adv soft interface. 145 * 146 * Return: true if the device is descendant of a batman-adv mesh interface (or 147 * if it is a batman-adv interface itself), false otherwise 148 */ 149 static bool batadv_is_on_batman_iface(const struct net_device *net_dev) 150 { 151 struct net *net = dev_net(net_dev); 152 struct net_device *parent_dev; 153 struct net *parent_net; 154 bool ret; 155 156 /* check if this is a batman-adv mesh interface */ 157 if (batadv_softif_is_valid(net_dev)) 158 return true; 159 160 /* no more parents..stop recursion */ 161 if (dev_get_iflink(net_dev) == 0 || 162 dev_get_iflink(net_dev) == net_dev->ifindex) 163 return false; 164 165 parent_net = batadv_getlink_net(net_dev, net); 166 167 /* recurse over the parent device */ 168 parent_dev = __dev_get_by_index((struct net *)parent_net, 169 dev_get_iflink(net_dev)); 170 /* if we got a NULL parent_dev there is something broken.. */ 171 if (!parent_dev) { 172 pr_err("Cannot find parent device\n"); 173 return false; 174 } 175 176 if (batadv_mutual_parents(net_dev, net, parent_dev, parent_net)) 177 return false; 178 179 ret = batadv_is_on_batman_iface(parent_dev); 180 181 return ret; 182 } 183 184 static bool batadv_is_valid_iface(const struct net_device *net_dev) 185 { 186 if (net_dev->flags & IFF_LOOPBACK) 187 return false; 188 189 if (net_dev->type != ARPHRD_ETHER) 190 return false; 191 192 if (net_dev->addr_len != ETH_ALEN) 193 return false; 194 195 /* no batman over batman */ 196 if (batadv_is_on_batman_iface(net_dev)) 197 return false; 198 199 return true; 200 } 201 202 /** 203 * batadv_get_real_netdevice() - check if the given netdev struct is a virtual 204 * interface on top of another 'real' interface 205 * @netdev: the device to check 206 * 207 * Callers must hold the rtnl semaphore. You may want batadv_get_real_netdev() 208 * instead of this. 209 * 210 * Return: the 'real' net device or the original net device and NULL in case 211 * of an error. 212 */ 213 static struct net_device *batadv_get_real_netdevice(struct net_device *netdev) 214 { 215 struct batadv_hard_iface *hard_iface = NULL; 216 struct net_device *real_netdev = NULL; 217 struct net *real_net; 218 struct net *net; 219 int ifindex; 220 221 ASSERT_RTNL(); 222 223 if (!netdev) 224 return NULL; 225 226 if (netdev->ifindex == dev_get_iflink(netdev)) { 227 dev_hold(netdev); 228 return netdev; 229 } 230 231 hard_iface = batadv_hardif_get_by_netdev(netdev); 232 if (!hard_iface || !hard_iface->soft_iface) 233 goto out; 234 235 net = dev_net(hard_iface->soft_iface); 236 ifindex = dev_get_iflink(netdev); 237 real_net = batadv_getlink_net(netdev, net); 238 real_netdev = dev_get_by_index(real_net, ifindex); 239 240 out: 241 if (hard_iface) 242 batadv_hardif_put(hard_iface); 243 return real_netdev; 244 } 245 246 /** 247 * batadv_get_real_netdev() - check if the given net_device struct is a virtual 248 * interface on top of another 'real' interface 249 * @net_device: the device to check 250 * 251 * Return: the 'real' net device or the original net device and NULL in case 252 * of an error. 253 */ 254 struct net_device *batadv_get_real_netdev(struct net_device *net_device) 255 { 256 struct net_device *real_netdev; 257 258 rtnl_lock(); 259 real_netdev = batadv_get_real_netdevice(net_device); 260 rtnl_unlock(); 261 262 return real_netdev; 263 } 264 265 /** 266 * batadv_is_wext_netdev() - check if the given net_device struct is a 267 * wext wifi interface 268 * @net_device: the device to check 269 * 270 * Return: true if the net device is a wext wireless device, false 271 * otherwise. 272 */ 273 static bool batadv_is_wext_netdev(struct net_device *net_device) 274 { 275 if (!net_device) 276 return false; 277 278 #ifdef CONFIG_WIRELESS_EXT 279 /* pre-cfg80211 drivers have to implement WEXT, so it is possible to 280 * check for wireless_handlers != NULL 281 */ 282 if (net_device->wireless_handlers) 283 return true; 284 #endif 285 286 return false; 287 } 288 289 /** 290 * batadv_is_cfg80211_netdev() - check if the given net_device struct is a 291 * cfg80211 wifi interface 292 * @net_device: the device to check 293 * 294 * Return: true if the net device is a cfg80211 wireless device, false 295 * otherwise. 296 */ 297 static bool batadv_is_cfg80211_netdev(struct net_device *net_device) 298 { 299 if (!net_device) 300 return false; 301 302 /* cfg80211 drivers have to set ieee80211_ptr */ 303 if (net_device->ieee80211_ptr) 304 return true; 305 306 return false; 307 } 308 309 /** 310 * batadv_wifi_flags_evaluate() - calculate wifi flags for net_device 311 * @net_device: the device to check 312 * 313 * Return: batadv_hard_iface_wifi_flags flags of the device 314 */ 315 static u32 batadv_wifi_flags_evaluate(struct net_device *net_device) 316 { 317 u32 wifi_flags = 0; 318 struct net_device *real_netdev; 319 320 if (batadv_is_wext_netdev(net_device)) 321 wifi_flags |= BATADV_HARDIF_WIFI_WEXT_DIRECT; 322 323 if (batadv_is_cfg80211_netdev(net_device)) 324 wifi_flags |= BATADV_HARDIF_WIFI_CFG80211_DIRECT; 325 326 real_netdev = batadv_get_real_netdevice(net_device); 327 if (!real_netdev) 328 return wifi_flags; 329 330 if (real_netdev == net_device) 331 goto out; 332 333 if (batadv_is_wext_netdev(real_netdev)) 334 wifi_flags |= BATADV_HARDIF_WIFI_WEXT_INDIRECT; 335 336 if (batadv_is_cfg80211_netdev(real_netdev)) 337 wifi_flags |= BATADV_HARDIF_WIFI_CFG80211_INDIRECT; 338 339 out: 340 dev_put(real_netdev); 341 return wifi_flags; 342 } 343 344 /** 345 * batadv_is_cfg80211_hardif() - check if the given hardif is a cfg80211 wifi 346 * interface 347 * @hard_iface: the device to check 348 * 349 * Return: true if the net device is a cfg80211 wireless device, false 350 * otherwise. 351 */ 352 bool batadv_is_cfg80211_hardif(struct batadv_hard_iface *hard_iface) 353 { 354 u32 allowed_flags = 0; 355 356 allowed_flags |= BATADV_HARDIF_WIFI_CFG80211_DIRECT; 357 allowed_flags |= BATADV_HARDIF_WIFI_CFG80211_INDIRECT; 358 359 return !!(hard_iface->wifi_flags & allowed_flags); 360 } 361 362 /** 363 * batadv_is_wifi_hardif() - check if the given hardif is a wifi interface 364 * @hard_iface: the device to check 365 * 366 * Return: true if the net device is a 802.11 wireless device, false otherwise. 367 */ 368 bool batadv_is_wifi_hardif(struct batadv_hard_iface *hard_iface) 369 { 370 if (!hard_iface) 371 return false; 372 373 return hard_iface->wifi_flags != 0; 374 } 375 376 /** 377 * batadv_hardif_no_broadcast() - check whether (re)broadcast is necessary 378 * @if_outgoing: the outgoing interface checked and considered for (re)broadcast 379 * @orig_addr: the originator of this packet 380 * @orig_neigh: originator address of the forwarder we just got the packet from 381 * (NULL if we originated) 382 * 383 * Checks whether a packet needs to be (re)broadcasted on the given interface. 384 * 385 * Return: 386 * BATADV_HARDIF_BCAST_NORECIPIENT: No neighbor on interface 387 * BATADV_HARDIF_BCAST_DUPFWD: Just one neighbor, but it is the forwarder 388 * BATADV_HARDIF_BCAST_DUPORIG: Just one neighbor, but it is the originator 389 * BATADV_HARDIF_BCAST_OK: Several neighbors, must broadcast 390 */ 391 int batadv_hardif_no_broadcast(struct batadv_hard_iface *if_outgoing, 392 u8 *orig_addr, u8 *orig_neigh) 393 { 394 struct batadv_hardif_neigh_node *hardif_neigh; 395 struct hlist_node *first; 396 int ret = BATADV_HARDIF_BCAST_OK; 397 398 rcu_read_lock(); 399 400 /* 0 neighbors -> no (re)broadcast */ 401 first = rcu_dereference(hlist_first_rcu(&if_outgoing->neigh_list)); 402 if (!first) { 403 ret = BATADV_HARDIF_BCAST_NORECIPIENT; 404 goto out; 405 } 406 407 /* >1 neighbors -> (re)brodcast */ 408 if (rcu_dereference(hlist_next_rcu(first))) 409 goto out; 410 411 hardif_neigh = hlist_entry(first, struct batadv_hardif_neigh_node, 412 list); 413 414 /* 1 neighbor, is the originator -> no rebroadcast */ 415 if (orig_addr && batadv_compare_eth(hardif_neigh->orig, orig_addr)) { 416 ret = BATADV_HARDIF_BCAST_DUPORIG; 417 /* 1 neighbor, is the one we received from -> no rebroadcast */ 418 } else if (orig_neigh && 419 batadv_compare_eth(hardif_neigh->orig, orig_neigh)) { 420 ret = BATADV_HARDIF_BCAST_DUPFWD; 421 } 422 423 out: 424 rcu_read_unlock(); 425 return ret; 426 } 427 428 static struct batadv_hard_iface * 429 batadv_hardif_get_active(const struct net_device *soft_iface) 430 { 431 struct batadv_hard_iface *hard_iface; 432 433 rcu_read_lock(); 434 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { 435 if (hard_iface->soft_iface != soft_iface) 436 continue; 437 438 if (hard_iface->if_status == BATADV_IF_ACTIVE && 439 kref_get_unless_zero(&hard_iface->refcount)) 440 goto out; 441 } 442 443 hard_iface = NULL; 444 445 out: 446 rcu_read_unlock(); 447 return hard_iface; 448 } 449 450 static void batadv_primary_if_update_addr(struct batadv_priv *bat_priv, 451 struct batadv_hard_iface *oldif) 452 { 453 struct batadv_hard_iface *primary_if; 454 455 primary_if = batadv_primary_if_get_selected(bat_priv); 456 if (!primary_if) 457 goto out; 458 459 batadv_dat_init_own_addr(bat_priv, primary_if); 460 batadv_bla_update_orig_address(bat_priv, primary_if, oldif); 461 out: 462 if (primary_if) 463 batadv_hardif_put(primary_if); 464 } 465 466 static void batadv_primary_if_select(struct batadv_priv *bat_priv, 467 struct batadv_hard_iface *new_hard_iface) 468 { 469 struct batadv_hard_iface *curr_hard_iface; 470 471 ASSERT_RTNL(); 472 473 if (new_hard_iface) 474 kref_get(&new_hard_iface->refcount); 475 476 curr_hard_iface = rcu_dereference_protected(bat_priv->primary_if, 1); 477 rcu_assign_pointer(bat_priv->primary_if, new_hard_iface); 478 479 if (!new_hard_iface) 480 goto out; 481 482 bat_priv->algo_ops->iface.primary_set(new_hard_iface); 483 batadv_primary_if_update_addr(bat_priv, curr_hard_iface); 484 485 out: 486 if (curr_hard_iface) 487 batadv_hardif_put(curr_hard_iface); 488 } 489 490 static bool 491 batadv_hardif_is_iface_up(const struct batadv_hard_iface *hard_iface) 492 { 493 if (hard_iface->net_dev->flags & IFF_UP) 494 return true; 495 496 return false; 497 } 498 499 static void batadv_check_known_mac_addr(const struct net_device *net_dev) 500 { 501 const struct batadv_hard_iface *hard_iface; 502 503 rcu_read_lock(); 504 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { 505 if (hard_iface->if_status != BATADV_IF_ACTIVE && 506 hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED) 507 continue; 508 509 if (hard_iface->net_dev == net_dev) 510 continue; 511 512 if (!batadv_compare_eth(hard_iface->net_dev->dev_addr, 513 net_dev->dev_addr)) 514 continue; 515 516 pr_warn("The newly added mac address (%pM) already exists on: %s\n", 517 net_dev->dev_addr, hard_iface->net_dev->name); 518 pr_warn("It is strongly recommended to keep mac addresses unique to avoid problems!\n"); 519 } 520 rcu_read_unlock(); 521 } 522 523 /** 524 * batadv_hardif_recalc_extra_skbroom() - Recalculate skbuff extra head/tailroom 525 * @soft_iface: netdev struct of the mesh interface 526 */ 527 static void batadv_hardif_recalc_extra_skbroom(struct net_device *soft_iface) 528 { 529 const struct batadv_hard_iface *hard_iface; 530 unsigned short lower_header_len = ETH_HLEN; 531 unsigned short lower_headroom = 0; 532 unsigned short lower_tailroom = 0; 533 unsigned short needed_headroom; 534 535 rcu_read_lock(); 536 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { 537 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE) 538 continue; 539 540 if (hard_iface->soft_iface != soft_iface) 541 continue; 542 543 lower_header_len = max_t(unsigned short, lower_header_len, 544 hard_iface->net_dev->hard_header_len); 545 546 lower_headroom = max_t(unsigned short, lower_headroom, 547 hard_iface->net_dev->needed_headroom); 548 549 lower_tailroom = max_t(unsigned short, lower_tailroom, 550 hard_iface->net_dev->needed_tailroom); 551 } 552 rcu_read_unlock(); 553 554 needed_headroom = lower_headroom + (lower_header_len - ETH_HLEN); 555 needed_headroom += batadv_max_header_len(); 556 557 soft_iface->needed_headroom = needed_headroom; 558 soft_iface->needed_tailroom = lower_tailroom; 559 } 560 561 /** 562 * batadv_hardif_min_mtu() - Calculate maximum MTU for soft interface 563 * @soft_iface: netdev struct of the soft interface 564 * 565 * Return: MTU for the soft-interface (limited by the minimal MTU of all active 566 * slave interfaces) 567 */ 568 int batadv_hardif_min_mtu(struct net_device *soft_iface) 569 { 570 struct batadv_priv *bat_priv = netdev_priv(soft_iface); 571 const struct batadv_hard_iface *hard_iface; 572 int min_mtu = INT_MAX; 573 574 rcu_read_lock(); 575 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { 576 if (hard_iface->if_status != BATADV_IF_ACTIVE && 577 hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED) 578 continue; 579 580 if (hard_iface->soft_iface != soft_iface) 581 continue; 582 583 min_mtu = min_t(int, hard_iface->net_dev->mtu, min_mtu); 584 } 585 rcu_read_unlock(); 586 587 if (atomic_read(&bat_priv->fragmentation) == 0) 588 goto out; 589 590 /* with fragmentation enabled the maximum size of internally generated 591 * packets such as translation table exchanges or tvlv containers, etc 592 * has to be calculated 593 */ 594 min_mtu = min_t(int, min_mtu, BATADV_FRAG_MAX_FRAG_SIZE); 595 min_mtu -= sizeof(struct batadv_frag_packet); 596 min_mtu *= BATADV_FRAG_MAX_FRAGMENTS; 597 598 out: 599 /* report to the other components the maximum amount of bytes that 600 * batman-adv can send over the wire (without considering the payload 601 * overhead). For example, this value is used by TT to compute the 602 * maximum local table table size 603 */ 604 atomic_set(&bat_priv->packet_size_max, min_mtu); 605 606 /* the real soft-interface MTU is computed by removing the payload 607 * overhead from the maximum amount of bytes that was just computed. 608 * 609 * However batman-adv does not support MTUs bigger than ETH_DATA_LEN 610 */ 611 return min_t(int, min_mtu - batadv_max_header_len(), ETH_DATA_LEN); 612 } 613 614 /** 615 * batadv_update_min_mtu() - Adjusts the MTU if a new interface with a smaller 616 * MTU appeared 617 * @soft_iface: netdev struct of the soft interface 618 */ 619 void batadv_update_min_mtu(struct net_device *soft_iface) 620 { 621 soft_iface->mtu = batadv_hardif_min_mtu(soft_iface); 622 623 /* Check if the local translate table should be cleaned up to match a 624 * new (and smaller) MTU. 625 */ 626 batadv_tt_local_resize_to_mtu(soft_iface); 627 } 628 629 static void 630 batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface) 631 { 632 struct batadv_priv *bat_priv; 633 struct batadv_hard_iface *primary_if = NULL; 634 635 if (hard_iface->if_status != BATADV_IF_INACTIVE) 636 goto out; 637 638 bat_priv = netdev_priv(hard_iface->soft_iface); 639 640 bat_priv->algo_ops->iface.update_mac(hard_iface); 641 hard_iface->if_status = BATADV_IF_TO_BE_ACTIVATED; 642 643 /* the first active interface becomes our primary interface or 644 * the next active interface after the old primary interface was removed 645 */ 646 primary_if = batadv_primary_if_get_selected(bat_priv); 647 if (!primary_if) 648 batadv_primary_if_select(bat_priv, hard_iface); 649 650 batadv_info(hard_iface->soft_iface, "Interface activated: %s\n", 651 hard_iface->net_dev->name); 652 653 batadv_update_min_mtu(hard_iface->soft_iface); 654 655 if (bat_priv->algo_ops->iface.activate) 656 bat_priv->algo_ops->iface.activate(hard_iface); 657 658 out: 659 if (primary_if) 660 batadv_hardif_put(primary_if); 661 } 662 663 static void 664 batadv_hardif_deactivate_interface(struct batadv_hard_iface *hard_iface) 665 { 666 if (hard_iface->if_status != BATADV_IF_ACTIVE && 667 hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED) 668 return; 669 670 hard_iface->if_status = BATADV_IF_INACTIVE; 671 672 batadv_info(hard_iface->soft_iface, "Interface deactivated: %s\n", 673 hard_iface->net_dev->name); 674 675 batadv_update_min_mtu(hard_iface->soft_iface); 676 } 677 678 /** 679 * batadv_master_del_slave() - remove hard_iface from the current master iface 680 * @slave: the interface enslaved in another master 681 * @master: the master from which slave has to be removed 682 * 683 * Invoke ndo_del_slave on master passing slave as argument. In this way slave 684 * is free'd and master can correctly change its internal state. 685 * 686 * Return: 0 on success, a negative value representing the error otherwise 687 */ 688 static int batadv_master_del_slave(struct batadv_hard_iface *slave, 689 struct net_device *master) 690 { 691 int ret; 692 693 if (!master) 694 return 0; 695 696 ret = -EBUSY; 697 if (master->netdev_ops->ndo_del_slave) 698 ret = master->netdev_ops->ndo_del_slave(master, slave->net_dev); 699 700 return ret; 701 } 702 703 /** 704 * batadv_hardif_enable_interface() - Enslave hard interface to soft interface 705 * @hard_iface: hard interface to add to soft interface 706 * @net: the applicable net namespace 707 * @iface_name: name of the soft interface 708 * 709 * Return: 0 on success or negative error number in case of failure 710 */ 711 int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface, 712 struct net *net, const char *iface_name) 713 { 714 struct batadv_priv *bat_priv; 715 struct net_device *soft_iface, *master; 716 __be16 ethertype = htons(ETH_P_BATMAN); 717 int max_header_len = batadv_max_header_len(); 718 int ret; 719 720 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE) 721 goto out; 722 723 kref_get(&hard_iface->refcount); 724 725 soft_iface = dev_get_by_name(net, iface_name); 726 727 if (!soft_iface) { 728 soft_iface = batadv_softif_create(net, iface_name); 729 730 if (!soft_iface) { 731 ret = -ENOMEM; 732 goto err; 733 } 734 735 /* dev_get_by_name() increases the reference counter for us */ 736 dev_hold(soft_iface); 737 } 738 739 if (!batadv_softif_is_valid(soft_iface)) { 740 pr_err("Can't create batman mesh interface %s: already exists as regular interface\n", 741 soft_iface->name); 742 ret = -EINVAL; 743 goto err_dev; 744 } 745 746 /* check if the interface is enslaved in another virtual one and 747 * in that case unlink it first 748 */ 749 master = netdev_master_upper_dev_get(hard_iface->net_dev); 750 ret = batadv_master_del_slave(hard_iface, master); 751 if (ret) 752 goto err_dev; 753 754 hard_iface->soft_iface = soft_iface; 755 bat_priv = netdev_priv(hard_iface->soft_iface); 756 757 ret = netdev_master_upper_dev_link(hard_iface->net_dev, 758 soft_iface, NULL, NULL, NULL); 759 if (ret) 760 goto err_dev; 761 762 ret = bat_priv->algo_ops->iface.enable(hard_iface); 763 if (ret < 0) 764 goto err_upper; 765 766 hard_iface->if_status = BATADV_IF_INACTIVE; 767 768 kref_get(&hard_iface->refcount); 769 hard_iface->batman_adv_ptype.type = ethertype; 770 hard_iface->batman_adv_ptype.func = batadv_batman_skb_recv; 771 hard_iface->batman_adv_ptype.dev = hard_iface->net_dev; 772 dev_add_pack(&hard_iface->batman_adv_ptype); 773 774 batadv_info(hard_iface->soft_iface, "Adding interface: %s\n", 775 hard_iface->net_dev->name); 776 777 if (atomic_read(&bat_priv->fragmentation) && 778 hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len) 779 batadv_info(hard_iface->soft_iface, 780 "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", 781 hard_iface->net_dev->name, hard_iface->net_dev->mtu, 782 ETH_DATA_LEN + max_header_len); 783 784 if (!atomic_read(&bat_priv->fragmentation) && 785 hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len) 786 batadv_info(hard_iface->soft_iface, 787 "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", 788 hard_iface->net_dev->name, hard_iface->net_dev->mtu, 789 ETH_DATA_LEN + max_header_len); 790 791 if (batadv_hardif_is_iface_up(hard_iface)) 792 batadv_hardif_activate_interface(hard_iface); 793 else 794 batadv_err(hard_iface->soft_iface, 795 "Not using interface %s (retrying later): interface not active\n", 796 hard_iface->net_dev->name); 797 798 batadv_hardif_recalc_extra_skbroom(soft_iface); 799 800 if (bat_priv->algo_ops->iface.enabled) 801 bat_priv->algo_ops->iface.enabled(hard_iface); 802 803 out: 804 return 0; 805 806 err_upper: 807 netdev_upper_dev_unlink(hard_iface->net_dev, soft_iface); 808 err_dev: 809 hard_iface->soft_iface = NULL; 810 dev_put(soft_iface); 811 err: 812 batadv_hardif_put(hard_iface); 813 return ret; 814 } 815 816 /** 817 * batadv_hardif_cnt() - get number of interfaces enslaved to soft interface 818 * @soft_iface: soft interface to check 819 * 820 * This function is only using RCU for locking - the result can therefore be 821 * off when another functions is modifying the list at the same time. The 822 * caller can use the rtnl_lock to make sure that the count is accurate. 823 * 824 * Return: number of connected/enslaved hard interfaces 825 */ 826 static size_t batadv_hardif_cnt(const struct net_device *soft_iface) 827 { 828 struct batadv_hard_iface *hard_iface; 829 size_t count = 0; 830 831 rcu_read_lock(); 832 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { 833 if (hard_iface->soft_iface != soft_iface) 834 continue; 835 836 count++; 837 } 838 rcu_read_unlock(); 839 840 return count; 841 } 842 843 /** 844 * batadv_hardif_disable_interface() - Remove hard interface from soft interface 845 * @hard_iface: hard interface to be removed 846 * @autodel: whether to delete soft interface when it doesn't contain any other 847 * slave interfaces 848 */ 849 void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface, 850 enum batadv_hard_if_cleanup autodel) 851 { 852 struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface); 853 struct batadv_hard_iface *primary_if = NULL; 854 855 batadv_hardif_deactivate_interface(hard_iface); 856 857 if (hard_iface->if_status != BATADV_IF_INACTIVE) 858 goto out; 859 860 batadv_info(hard_iface->soft_iface, "Removing interface: %s\n", 861 hard_iface->net_dev->name); 862 dev_remove_pack(&hard_iface->batman_adv_ptype); 863 batadv_hardif_put(hard_iface); 864 865 primary_if = batadv_primary_if_get_selected(bat_priv); 866 if (hard_iface == primary_if) { 867 struct batadv_hard_iface *new_if; 868 869 new_if = batadv_hardif_get_active(hard_iface->soft_iface); 870 batadv_primary_if_select(bat_priv, new_if); 871 872 if (new_if) 873 batadv_hardif_put(new_if); 874 } 875 876 bat_priv->algo_ops->iface.disable(hard_iface); 877 hard_iface->if_status = BATADV_IF_NOT_IN_USE; 878 879 /* delete all references to this hard_iface */ 880 batadv_purge_orig_ref(bat_priv); 881 batadv_purge_outstanding_packets(bat_priv, hard_iface); 882 dev_put(hard_iface->soft_iface); 883 884 netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface); 885 batadv_hardif_recalc_extra_skbroom(hard_iface->soft_iface); 886 887 /* nobody uses this interface anymore */ 888 if (batadv_hardif_cnt(hard_iface->soft_iface) <= 1) { 889 batadv_gw_check_client_stop(bat_priv); 890 891 if (autodel == BATADV_IF_CLEANUP_AUTO) 892 batadv_softif_destroy_sysfs(hard_iface->soft_iface); 893 } 894 895 hard_iface->soft_iface = NULL; 896 batadv_hardif_put(hard_iface); 897 898 out: 899 if (primary_if) 900 batadv_hardif_put(primary_if); 901 } 902 903 static struct batadv_hard_iface * 904 batadv_hardif_add_interface(struct net_device *net_dev) 905 { 906 struct batadv_hard_iface *hard_iface; 907 int ret; 908 909 ASSERT_RTNL(); 910 911 if (!batadv_is_valid_iface(net_dev)) 912 goto out; 913 914 dev_hold(net_dev); 915 916 hard_iface = kzalloc(sizeof(*hard_iface), GFP_ATOMIC); 917 if (!hard_iface) 918 goto release_dev; 919 920 ret = batadv_sysfs_add_hardif(&hard_iface->hardif_obj, net_dev); 921 if (ret) 922 goto free_if; 923 924 hard_iface->net_dev = net_dev; 925 hard_iface->soft_iface = NULL; 926 hard_iface->if_status = BATADV_IF_NOT_IN_USE; 927 928 batadv_debugfs_add_hardif(hard_iface); 929 930 INIT_LIST_HEAD(&hard_iface->list); 931 INIT_HLIST_HEAD(&hard_iface->neigh_list); 932 933 mutex_init(&hard_iface->bat_iv.ogm_buff_mutex); 934 spin_lock_init(&hard_iface->neigh_list_lock); 935 kref_init(&hard_iface->refcount); 936 937 hard_iface->num_bcasts = BATADV_NUM_BCASTS_DEFAULT; 938 hard_iface->wifi_flags = batadv_wifi_flags_evaluate(net_dev); 939 if (batadv_is_wifi_hardif(hard_iface)) 940 hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS; 941 942 batadv_v_hardif_init(hard_iface); 943 944 batadv_check_known_mac_addr(hard_iface->net_dev); 945 kref_get(&hard_iface->refcount); 946 list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list); 947 batadv_hardif_generation++; 948 949 return hard_iface; 950 951 free_if: 952 kfree(hard_iface); 953 release_dev: 954 dev_put(net_dev); 955 out: 956 return NULL; 957 } 958 959 static void batadv_hardif_remove_interface(struct batadv_hard_iface *hard_iface) 960 { 961 ASSERT_RTNL(); 962 963 /* first deactivate interface */ 964 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE) 965 batadv_hardif_disable_interface(hard_iface, 966 BATADV_IF_CLEANUP_KEEP); 967 968 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE) 969 return; 970 971 hard_iface->if_status = BATADV_IF_TO_BE_REMOVED; 972 batadv_debugfs_del_hardif(hard_iface); 973 batadv_sysfs_del_hardif(&hard_iface->hardif_obj); 974 batadv_hardif_put(hard_iface); 975 } 976 977 /** 978 * batadv_hardif_remove_interfaces() - Remove all hard interfaces 979 */ 980 void batadv_hardif_remove_interfaces(void) 981 { 982 struct batadv_hard_iface *hard_iface, *hard_iface_tmp; 983 984 rtnl_lock(); 985 list_for_each_entry_safe(hard_iface, hard_iface_tmp, 986 &batadv_hardif_list, list) { 987 list_del_rcu(&hard_iface->list); 988 batadv_hardif_generation++; 989 batadv_hardif_remove_interface(hard_iface); 990 } 991 rtnl_unlock(); 992 } 993 994 /** 995 * batadv_hard_if_event_softif() - Handle events for soft interfaces 996 * @event: NETDEV_* event to handle 997 * @net_dev: net_device which generated an event 998 * 999 * Return: NOTIFY_* result 1000 */ 1001 static int batadv_hard_if_event_softif(unsigned long event, 1002 struct net_device *net_dev) 1003 { 1004 struct batadv_priv *bat_priv; 1005 1006 switch (event) { 1007 case NETDEV_REGISTER: 1008 batadv_sysfs_add_meshif(net_dev); 1009 bat_priv = netdev_priv(net_dev); 1010 batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS); 1011 break; 1012 case NETDEV_CHANGENAME: 1013 batadv_debugfs_rename_meshif(net_dev); 1014 break; 1015 } 1016 1017 return NOTIFY_DONE; 1018 } 1019 1020 static int batadv_hard_if_event(struct notifier_block *this, 1021 unsigned long event, void *ptr) 1022 { 1023 struct net_device *net_dev = netdev_notifier_info_to_dev(ptr); 1024 struct batadv_hard_iface *hard_iface; 1025 struct batadv_hard_iface *primary_if = NULL; 1026 struct batadv_priv *bat_priv; 1027 1028 if (batadv_softif_is_valid(net_dev)) 1029 return batadv_hard_if_event_softif(event, net_dev); 1030 1031 hard_iface = batadv_hardif_get_by_netdev(net_dev); 1032 if (!hard_iface && (event == NETDEV_REGISTER || 1033 event == NETDEV_POST_TYPE_CHANGE)) 1034 hard_iface = batadv_hardif_add_interface(net_dev); 1035 1036 if (!hard_iface) 1037 goto out; 1038 1039 switch (event) { 1040 case NETDEV_UP: 1041 batadv_hardif_activate_interface(hard_iface); 1042 break; 1043 case NETDEV_GOING_DOWN: 1044 case NETDEV_DOWN: 1045 batadv_hardif_deactivate_interface(hard_iface); 1046 break; 1047 case NETDEV_UNREGISTER: 1048 case NETDEV_PRE_TYPE_CHANGE: 1049 list_del_rcu(&hard_iface->list); 1050 batadv_hardif_generation++; 1051 1052 batadv_hardif_remove_interface(hard_iface); 1053 break; 1054 case NETDEV_CHANGEMTU: 1055 if (hard_iface->soft_iface) 1056 batadv_update_min_mtu(hard_iface->soft_iface); 1057 break; 1058 case NETDEV_CHANGEADDR: 1059 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE) 1060 goto hardif_put; 1061 1062 batadv_check_known_mac_addr(hard_iface->net_dev); 1063 1064 bat_priv = netdev_priv(hard_iface->soft_iface); 1065 bat_priv->algo_ops->iface.update_mac(hard_iface); 1066 1067 primary_if = batadv_primary_if_get_selected(bat_priv); 1068 if (!primary_if) 1069 goto hardif_put; 1070 1071 if (hard_iface == primary_if) 1072 batadv_primary_if_update_addr(bat_priv, NULL); 1073 break; 1074 case NETDEV_CHANGEUPPER: 1075 hard_iface->wifi_flags = batadv_wifi_flags_evaluate(net_dev); 1076 if (batadv_is_wifi_hardif(hard_iface)) 1077 hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS; 1078 break; 1079 case NETDEV_CHANGENAME: 1080 batadv_debugfs_rename_hardif(hard_iface); 1081 break; 1082 default: 1083 break; 1084 } 1085 1086 hardif_put: 1087 batadv_hardif_put(hard_iface); 1088 out: 1089 if (primary_if) 1090 batadv_hardif_put(primary_if); 1091 return NOTIFY_DONE; 1092 } 1093 1094 struct notifier_block batadv_hard_if_notifier = { 1095 .notifier_call = batadv_hard_if_event, 1096 }; 1097