rjw | 1f88458 | 2022-01-06 17:20:42 +0800 | [diff] [blame^] | 1 | /* Copyright (C) 2007-2017 B.A.T.M.A.N. contributors: |
| 2 | * |
| 3 | * Marek Lindner, Simon Wunderlich |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or |
| 6 | * modify it under the terms of version 2 of the GNU General Public |
| 7 | * License as published by the Free Software Foundation. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, but |
| 10 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | * General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License |
| 15 | * along with this program; if not, see <http://www.gnu.org/licenses/>. |
| 16 | */ |
| 17 | |
| 18 | #include "hard-interface.h" |
| 19 | #include "main.h" |
| 20 | |
| 21 | #include <linux/atomic.h> |
| 22 | #include <linux/byteorder/generic.h> |
| 23 | #include <linux/errno.h> |
| 24 | #include <linux/fs.h> |
| 25 | #include <linux/if.h> |
| 26 | #include <linux/if_arp.h> |
| 27 | #include <linux/if_ether.h> |
| 28 | #include <linux/kernel.h> |
| 29 | #include <linux/kref.h> |
| 30 | #include <linux/list.h> |
| 31 | #include <linux/mutex.h> |
| 32 | #include <linux/netdevice.h> |
| 33 | #include <linux/printk.h> |
| 34 | #include <linux/rculist.h> |
| 35 | #include <linux/rtnetlink.h> |
| 36 | #include <linux/slab.h> |
| 37 | #include <linux/spinlock.h> |
| 38 | #include <net/net_namespace.h> |
| 39 | #include <net/rtnetlink.h> |
| 40 | |
| 41 | #include "bat_v.h" |
| 42 | #include "bridge_loop_avoidance.h" |
| 43 | #include "debugfs.h" |
| 44 | #include "distributed-arp-table.h" |
| 45 | #include "gateway_client.h" |
| 46 | #include "log.h" |
| 47 | #include "originator.h" |
| 48 | #include "packet.h" |
| 49 | #include "send.h" |
| 50 | #include "soft-interface.h" |
| 51 | #include "sysfs.h" |
| 52 | #include "translation-table.h" |
| 53 | |
| 54 | /** |
| 55 | * batadv_hardif_release - release hard interface from lists and queue for |
| 56 | * free after rcu grace period |
| 57 | * @ref: kref pointer of the hard interface |
| 58 | */ |
| 59 | void batadv_hardif_release(struct kref *ref) |
| 60 | { |
| 61 | struct batadv_hard_iface *hard_iface; |
| 62 | |
| 63 | hard_iface = container_of(ref, struct batadv_hard_iface, refcount); |
| 64 | dev_put(hard_iface->net_dev); |
| 65 | |
| 66 | kfree_rcu(hard_iface, rcu); |
| 67 | } |
| 68 | |
| 69 | struct batadv_hard_iface * |
| 70 | batadv_hardif_get_by_netdev(const struct net_device *net_dev) |
| 71 | { |
| 72 | struct batadv_hard_iface *hard_iface; |
| 73 | |
| 74 | rcu_read_lock(); |
| 75 | list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { |
| 76 | if (hard_iface->net_dev == net_dev && |
| 77 | kref_get_unless_zero(&hard_iface->refcount)) |
| 78 | goto out; |
| 79 | } |
| 80 | |
| 81 | hard_iface = NULL; |
| 82 | |
| 83 | out: |
| 84 | rcu_read_unlock(); |
| 85 | return hard_iface; |
| 86 | } |
| 87 | |
| 88 | /** |
| 89 | * batadv_getlink_net - return link net namespace (of use fallback) |
| 90 | * @netdev: net_device to check |
| 91 | * @fallback_net: return in case get_link_net is not available for @netdev |
| 92 | * |
| 93 | * Return: result of rtnl_link_ops->get_link_net or @fallback_net |
| 94 | */ |
| 95 | static struct net *batadv_getlink_net(const struct net_device *netdev, |
| 96 | struct net *fallback_net) |
| 97 | { |
| 98 | if (!netdev->rtnl_link_ops) |
| 99 | return fallback_net; |
| 100 | |
| 101 | if (!netdev->rtnl_link_ops->get_link_net) |
| 102 | return fallback_net; |
| 103 | |
| 104 | return netdev->rtnl_link_ops->get_link_net(netdev); |
| 105 | } |
| 106 | |
| 107 | /** |
| 108 | * batadv_mutual_parents - check if two devices are each others parent |
| 109 | * @dev1: 1st net dev |
| 110 | * @net1: 1st devices netns |
| 111 | * @dev2: 2nd net dev |
| 112 | * @net2: 2nd devices netns |
| 113 | * |
| 114 | * veth devices come in pairs and each is the parent of the other! |
| 115 | * |
| 116 | * Return: true if the devices are each others parent, otherwise false |
| 117 | */ |
| 118 | static bool batadv_mutual_parents(const struct net_device *dev1, |
| 119 | struct net *net1, |
| 120 | const struct net_device *dev2, |
| 121 | struct net *net2) |
| 122 | { |
| 123 | int dev1_parent_iflink = dev_get_iflink(dev1); |
| 124 | int dev2_parent_iflink = dev_get_iflink(dev2); |
| 125 | const struct net *dev1_parent_net; |
| 126 | const struct net *dev2_parent_net; |
| 127 | |
| 128 | dev1_parent_net = batadv_getlink_net(dev1, net1); |
| 129 | dev2_parent_net = batadv_getlink_net(dev2, net2); |
| 130 | |
| 131 | if (!dev1_parent_iflink || !dev2_parent_iflink) |
| 132 | return false; |
| 133 | |
| 134 | return (dev1_parent_iflink == dev2->ifindex) && |
| 135 | (dev2_parent_iflink == dev1->ifindex) && |
| 136 | net_eq(dev1_parent_net, net2) && |
| 137 | net_eq(dev2_parent_net, net1); |
| 138 | } |
| 139 | |
| 140 | /** |
| 141 | * batadv_is_on_batman_iface - check if a device is a batman iface descendant |
| 142 | * @net_dev: the device to check |
| 143 | * |
| 144 | * If the user creates any virtual device on top of a batman-adv interface, it |
| 145 | * is important to prevent this new interface to be used to create a new mesh |
| 146 | * network (this behaviour would lead to a batman-over-batman configuration). |
| 147 | * This function recursively checks all the fathers of the device passed as |
| 148 | * argument looking for a batman-adv soft interface. |
| 149 | * |
| 150 | * Return: true if the device is descendant of a batman-adv mesh interface (or |
| 151 | * if it is a batman-adv interface itself), false otherwise |
| 152 | */ |
| 153 | static bool batadv_is_on_batman_iface(const struct net_device *net_dev) |
| 154 | { |
| 155 | struct net *net = dev_net(net_dev); |
| 156 | struct net_device *parent_dev; |
| 157 | struct net *parent_net; |
| 158 | bool ret; |
| 159 | |
| 160 | /* check if this is a batman-adv mesh interface */ |
| 161 | if (batadv_softif_is_valid(net_dev)) |
| 162 | return true; |
| 163 | |
| 164 | /* no more parents..stop recursion */ |
| 165 | if (dev_get_iflink(net_dev) == 0 || |
| 166 | dev_get_iflink(net_dev) == net_dev->ifindex) |
| 167 | return false; |
| 168 | |
| 169 | parent_net = batadv_getlink_net(net_dev, net); |
| 170 | |
| 171 | /* recurse over the parent device */ |
| 172 | parent_dev = __dev_get_by_index((struct net *)parent_net, |
| 173 | dev_get_iflink(net_dev)); |
| 174 | /* if we got a NULL parent_dev there is something broken.. */ |
| 175 | if (!parent_dev) { |
| 176 | pr_err("Cannot find parent device\n"); |
| 177 | return false; |
| 178 | } |
| 179 | |
| 180 | if (batadv_mutual_parents(net_dev, net, parent_dev, parent_net)) |
| 181 | return false; |
| 182 | |
| 183 | ret = batadv_is_on_batman_iface(parent_dev); |
| 184 | |
| 185 | return ret; |
| 186 | } |
| 187 | |
| 188 | static bool batadv_is_valid_iface(const struct net_device *net_dev) |
| 189 | { |
| 190 | if (net_dev->flags & IFF_LOOPBACK) |
| 191 | return false; |
| 192 | |
| 193 | if (net_dev->type != ARPHRD_ETHER) |
| 194 | return false; |
| 195 | |
| 196 | if (net_dev->addr_len != ETH_ALEN) |
| 197 | return false; |
| 198 | |
| 199 | /* no batman over batman */ |
| 200 | if (batadv_is_on_batman_iface(net_dev)) |
| 201 | return false; |
| 202 | |
| 203 | return true; |
| 204 | } |
| 205 | |
| 206 | /** |
| 207 | * batadv_get_real_netdevice - check if the given netdev struct is a virtual |
| 208 | * interface on top of another 'real' interface |
| 209 | * @netdev: the device to check |
| 210 | * |
| 211 | * Callers must hold the rtnl semaphore. You may want batadv_get_real_netdev() |
| 212 | * instead of this. |
| 213 | * |
| 214 | * Return: the 'real' net device or the original net device and NULL in case |
| 215 | * of an error. |
| 216 | */ |
| 217 | static struct net_device *batadv_get_real_netdevice(struct net_device *netdev) |
| 218 | { |
| 219 | struct batadv_hard_iface *hard_iface = NULL; |
| 220 | struct net_device *real_netdev = NULL; |
| 221 | struct net *real_net; |
| 222 | struct net *net; |
| 223 | int ifindex; |
| 224 | |
| 225 | ASSERT_RTNL(); |
| 226 | |
| 227 | if (!netdev) |
| 228 | return NULL; |
| 229 | |
| 230 | if (netdev->ifindex == dev_get_iflink(netdev)) { |
| 231 | dev_hold(netdev); |
| 232 | return netdev; |
| 233 | } |
| 234 | |
| 235 | hard_iface = batadv_hardif_get_by_netdev(netdev); |
| 236 | if (!hard_iface || !hard_iface->soft_iface) |
| 237 | goto out; |
| 238 | |
| 239 | net = dev_net(hard_iface->soft_iface); |
| 240 | ifindex = dev_get_iflink(netdev); |
| 241 | real_net = batadv_getlink_net(netdev, net); |
| 242 | real_netdev = dev_get_by_index(real_net, ifindex); |
| 243 | |
| 244 | out: |
| 245 | if (hard_iface) |
| 246 | batadv_hardif_put(hard_iface); |
| 247 | return real_netdev; |
| 248 | } |
| 249 | |
| 250 | /** |
| 251 | * batadv_get_real_netdev - check if the given net_device struct is a virtual |
| 252 | * interface on top of another 'real' interface |
| 253 | * @net_device: the device to check |
| 254 | * |
| 255 | * Return: the 'real' net device or the original net device and NULL in case |
| 256 | * of an error. |
| 257 | */ |
| 258 | struct net_device *batadv_get_real_netdev(struct net_device *net_device) |
| 259 | { |
| 260 | struct net_device *real_netdev; |
| 261 | |
| 262 | rtnl_lock(); |
| 263 | real_netdev = batadv_get_real_netdevice(net_device); |
| 264 | rtnl_unlock(); |
| 265 | |
| 266 | return real_netdev; |
| 267 | } |
| 268 | |
| 269 | /** |
| 270 | * batadv_is_wext_netdev - check if the given net_device struct is a |
| 271 | * wext wifi interface |
| 272 | * @net_device: the device to check |
| 273 | * |
| 274 | * Return: true if the net device is a wext wireless device, false |
| 275 | * otherwise. |
| 276 | */ |
| 277 | static bool batadv_is_wext_netdev(struct net_device *net_device) |
| 278 | { |
| 279 | if (!net_device) |
| 280 | return false; |
| 281 | |
| 282 | #ifdef CONFIG_WIRELESS_EXT |
| 283 | /* pre-cfg80211 drivers have to implement WEXT, so it is possible to |
| 284 | * check for wireless_handlers != NULL |
| 285 | */ |
| 286 | if (net_device->wireless_handlers) |
| 287 | return true; |
| 288 | #endif |
| 289 | |
| 290 | return false; |
| 291 | } |
| 292 | |
| 293 | /** |
| 294 | * batadv_is_cfg80211_netdev - check if the given net_device struct is a |
| 295 | * cfg80211 wifi interface |
| 296 | * @net_device: the device to check |
| 297 | * |
| 298 | * Return: true if the net device is a cfg80211 wireless device, false |
| 299 | * otherwise. |
| 300 | */ |
| 301 | static bool batadv_is_cfg80211_netdev(struct net_device *net_device) |
| 302 | { |
| 303 | if (!net_device) |
| 304 | return false; |
| 305 | |
| 306 | /* cfg80211 drivers have to set ieee80211_ptr */ |
| 307 | if (net_device->ieee80211_ptr) |
| 308 | return true; |
| 309 | |
| 310 | return false; |
| 311 | } |
| 312 | |
| 313 | /** |
| 314 | * batadv_wifi_flags_evaluate - calculate wifi flags for net_device |
| 315 | * @net_device: the device to check |
| 316 | * |
| 317 | * Return: batadv_hard_iface_wifi_flags flags of the device |
| 318 | */ |
| 319 | static u32 batadv_wifi_flags_evaluate(struct net_device *net_device) |
| 320 | { |
| 321 | u32 wifi_flags = 0; |
| 322 | struct net_device *real_netdev; |
| 323 | |
| 324 | if (batadv_is_wext_netdev(net_device)) |
| 325 | wifi_flags |= BATADV_HARDIF_WIFI_WEXT_DIRECT; |
| 326 | |
| 327 | if (batadv_is_cfg80211_netdev(net_device)) |
| 328 | wifi_flags |= BATADV_HARDIF_WIFI_CFG80211_DIRECT; |
| 329 | |
| 330 | real_netdev = batadv_get_real_netdevice(net_device); |
| 331 | if (!real_netdev) |
| 332 | return wifi_flags; |
| 333 | |
| 334 | if (real_netdev == net_device) |
| 335 | goto out; |
| 336 | |
| 337 | if (batadv_is_wext_netdev(real_netdev)) |
| 338 | wifi_flags |= BATADV_HARDIF_WIFI_WEXT_INDIRECT; |
| 339 | |
| 340 | if (batadv_is_cfg80211_netdev(real_netdev)) |
| 341 | wifi_flags |= BATADV_HARDIF_WIFI_CFG80211_INDIRECT; |
| 342 | |
| 343 | out: |
| 344 | dev_put(real_netdev); |
| 345 | return wifi_flags; |
| 346 | } |
| 347 | |
| 348 | /** |
| 349 | * batadv_is_cfg80211_hardif - check if the given hardif is a cfg80211 wifi |
| 350 | * interface |
| 351 | * @hard_iface: the device to check |
| 352 | * |
| 353 | * Return: true if the net device is a cfg80211 wireless device, false |
| 354 | * otherwise. |
| 355 | */ |
| 356 | bool batadv_is_cfg80211_hardif(struct batadv_hard_iface *hard_iface) |
| 357 | { |
| 358 | u32 allowed_flags = 0; |
| 359 | |
| 360 | allowed_flags |= BATADV_HARDIF_WIFI_CFG80211_DIRECT; |
| 361 | allowed_flags |= BATADV_HARDIF_WIFI_CFG80211_INDIRECT; |
| 362 | |
| 363 | return !!(hard_iface->wifi_flags & allowed_flags); |
| 364 | } |
| 365 | |
| 366 | /** |
| 367 | * batadv_is_wifi_hardif - check if the given hardif is a wifi interface |
| 368 | * @hard_iface: the device to check |
| 369 | * |
| 370 | * Return: true if the net device is a 802.11 wireless device, false otherwise. |
| 371 | */ |
| 372 | bool batadv_is_wifi_hardif(struct batadv_hard_iface *hard_iface) |
| 373 | { |
| 374 | if (!hard_iface) |
| 375 | return false; |
| 376 | |
| 377 | return hard_iface->wifi_flags != 0; |
| 378 | } |
| 379 | |
| 380 | /** |
| 381 | * batadv_hardif_no_broadcast - check whether (re)broadcast is necessary |
| 382 | * @if_outgoing: the outgoing interface checked and considered for (re)broadcast |
| 383 | * @orig_addr: the originator of this packet |
| 384 | * @orig_neigh: originator address of the forwarder we just got the packet from |
| 385 | * (NULL if we originated) |
| 386 | * |
| 387 | * Checks whether a packet needs to be (re)broadcasted on the given interface. |
| 388 | * |
| 389 | * Return: |
| 390 | * BATADV_HARDIF_BCAST_NORECIPIENT: No neighbor on interface |
| 391 | * BATADV_HARDIF_BCAST_DUPFWD: Just one neighbor, but it is the forwarder |
| 392 | * BATADV_HARDIF_BCAST_DUPORIG: Just one neighbor, but it is the originator |
| 393 | * BATADV_HARDIF_BCAST_OK: Several neighbors, must broadcast |
| 394 | */ |
| 395 | int batadv_hardif_no_broadcast(struct batadv_hard_iface *if_outgoing, |
| 396 | u8 *orig_addr, u8 *orig_neigh) |
| 397 | { |
| 398 | struct batadv_hardif_neigh_node *hardif_neigh; |
| 399 | struct hlist_node *first; |
| 400 | int ret = BATADV_HARDIF_BCAST_OK; |
| 401 | |
| 402 | rcu_read_lock(); |
| 403 | |
| 404 | /* 0 neighbors -> no (re)broadcast */ |
| 405 | first = rcu_dereference(hlist_first_rcu(&if_outgoing->neigh_list)); |
| 406 | if (!first) { |
| 407 | ret = BATADV_HARDIF_BCAST_NORECIPIENT; |
| 408 | goto out; |
| 409 | } |
| 410 | |
| 411 | /* >1 neighbors -> (re)brodcast */ |
| 412 | if (rcu_dereference(hlist_next_rcu(first))) |
| 413 | goto out; |
| 414 | |
| 415 | hardif_neigh = hlist_entry(first, struct batadv_hardif_neigh_node, |
| 416 | list); |
| 417 | |
| 418 | /* 1 neighbor, is the originator -> no rebroadcast */ |
| 419 | if (orig_addr && batadv_compare_eth(hardif_neigh->orig, orig_addr)) { |
| 420 | ret = BATADV_HARDIF_BCAST_DUPORIG; |
| 421 | /* 1 neighbor, is the one we received from -> no rebroadcast */ |
| 422 | } else if (orig_neigh && |
| 423 | batadv_compare_eth(hardif_neigh->orig, orig_neigh)) { |
| 424 | ret = BATADV_HARDIF_BCAST_DUPFWD; |
| 425 | } |
| 426 | |
| 427 | out: |
| 428 | rcu_read_unlock(); |
| 429 | return ret; |
| 430 | } |
| 431 | |
| 432 | static struct batadv_hard_iface * |
| 433 | batadv_hardif_get_active(const struct net_device *soft_iface) |
| 434 | { |
| 435 | struct batadv_hard_iface *hard_iface; |
| 436 | |
| 437 | rcu_read_lock(); |
| 438 | list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { |
| 439 | if (hard_iface->soft_iface != soft_iface) |
| 440 | continue; |
| 441 | |
| 442 | if (hard_iface->if_status == BATADV_IF_ACTIVE && |
| 443 | kref_get_unless_zero(&hard_iface->refcount)) |
| 444 | goto out; |
| 445 | } |
| 446 | |
| 447 | hard_iface = NULL; |
| 448 | |
| 449 | out: |
| 450 | rcu_read_unlock(); |
| 451 | return hard_iface; |
| 452 | } |
| 453 | |
| 454 | static void batadv_primary_if_update_addr(struct batadv_priv *bat_priv, |
| 455 | struct batadv_hard_iface *oldif) |
| 456 | { |
| 457 | struct batadv_hard_iface *primary_if; |
| 458 | |
| 459 | primary_if = batadv_primary_if_get_selected(bat_priv); |
| 460 | if (!primary_if) |
| 461 | goto out; |
| 462 | |
| 463 | batadv_dat_init_own_addr(bat_priv, primary_if); |
| 464 | batadv_bla_update_orig_address(bat_priv, primary_if, oldif); |
| 465 | out: |
| 466 | if (primary_if) |
| 467 | batadv_hardif_put(primary_if); |
| 468 | } |
| 469 | |
| 470 | static void batadv_primary_if_select(struct batadv_priv *bat_priv, |
| 471 | struct batadv_hard_iface *new_hard_iface) |
| 472 | { |
| 473 | struct batadv_hard_iface *curr_hard_iface; |
| 474 | |
| 475 | ASSERT_RTNL(); |
| 476 | |
| 477 | if (new_hard_iface) |
| 478 | kref_get(&new_hard_iface->refcount); |
| 479 | |
| 480 | curr_hard_iface = rcu_dereference_protected(bat_priv->primary_if, 1); |
| 481 | rcu_assign_pointer(bat_priv->primary_if, new_hard_iface); |
| 482 | |
| 483 | if (!new_hard_iface) |
| 484 | goto out; |
| 485 | |
| 486 | bat_priv->algo_ops->iface.primary_set(new_hard_iface); |
| 487 | batadv_primary_if_update_addr(bat_priv, curr_hard_iface); |
| 488 | |
| 489 | out: |
| 490 | if (curr_hard_iface) |
| 491 | batadv_hardif_put(curr_hard_iface); |
| 492 | } |
| 493 | |
| 494 | static bool |
| 495 | batadv_hardif_is_iface_up(const struct batadv_hard_iface *hard_iface) |
| 496 | { |
| 497 | if (hard_iface->net_dev->flags & IFF_UP) |
| 498 | return true; |
| 499 | |
| 500 | return false; |
| 501 | } |
| 502 | |
| 503 | static void batadv_check_known_mac_addr(const struct net_device *net_dev) |
| 504 | { |
| 505 | const struct batadv_hard_iface *hard_iface; |
| 506 | |
| 507 | rcu_read_lock(); |
| 508 | list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { |
| 509 | if ((hard_iface->if_status != BATADV_IF_ACTIVE) && |
| 510 | (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED)) |
| 511 | continue; |
| 512 | |
| 513 | if (hard_iface->net_dev == net_dev) |
| 514 | continue; |
| 515 | |
| 516 | if (!batadv_compare_eth(hard_iface->net_dev->dev_addr, |
| 517 | net_dev->dev_addr)) |
| 518 | continue; |
| 519 | |
| 520 | pr_warn("The newly added mac address (%pM) already exists on: %s\n", |
| 521 | net_dev->dev_addr, hard_iface->net_dev->name); |
| 522 | pr_warn("It is strongly recommended to keep mac addresses unique to avoid problems!\n"); |
| 523 | } |
| 524 | rcu_read_unlock(); |
| 525 | } |
| 526 | |
| 527 | /** |
| 528 | * batadv_hardif_recalc_extra_skbroom() - Recalculate skbuff extra head/tailroom |
| 529 | * @soft_iface: netdev struct of the mesh interface |
| 530 | */ |
| 531 | static void batadv_hardif_recalc_extra_skbroom(struct net_device *soft_iface) |
| 532 | { |
| 533 | const struct batadv_hard_iface *hard_iface; |
| 534 | unsigned short lower_header_len = ETH_HLEN; |
| 535 | unsigned short lower_headroom = 0; |
| 536 | unsigned short lower_tailroom = 0; |
| 537 | unsigned short needed_headroom; |
| 538 | |
| 539 | rcu_read_lock(); |
| 540 | list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { |
| 541 | if (hard_iface->if_status == BATADV_IF_NOT_IN_USE) |
| 542 | continue; |
| 543 | |
| 544 | if (hard_iface->soft_iface != soft_iface) |
| 545 | continue; |
| 546 | |
| 547 | lower_header_len = max_t(unsigned short, lower_header_len, |
| 548 | hard_iface->net_dev->hard_header_len); |
| 549 | |
| 550 | lower_headroom = max_t(unsigned short, lower_headroom, |
| 551 | hard_iface->net_dev->needed_headroom); |
| 552 | |
| 553 | lower_tailroom = max_t(unsigned short, lower_tailroom, |
| 554 | hard_iface->net_dev->needed_tailroom); |
| 555 | } |
| 556 | rcu_read_unlock(); |
| 557 | |
| 558 | needed_headroom = lower_headroom + (lower_header_len - ETH_HLEN); |
| 559 | needed_headroom += batadv_max_header_len(); |
| 560 | |
| 561 | soft_iface->needed_headroom = needed_headroom; |
| 562 | soft_iface->needed_tailroom = lower_tailroom; |
| 563 | } |
| 564 | |
| 565 | int batadv_hardif_min_mtu(struct net_device *soft_iface) |
| 566 | { |
| 567 | struct batadv_priv *bat_priv = netdev_priv(soft_iface); |
| 568 | const struct batadv_hard_iface *hard_iface; |
| 569 | int min_mtu = INT_MAX; |
| 570 | |
| 571 | rcu_read_lock(); |
| 572 | list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { |
| 573 | if ((hard_iface->if_status != BATADV_IF_ACTIVE) && |
| 574 | (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED)) |
| 575 | continue; |
| 576 | |
| 577 | if (hard_iface->soft_iface != soft_iface) |
| 578 | continue; |
| 579 | |
| 580 | min_mtu = min_t(int, hard_iface->net_dev->mtu, min_mtu); |
| 581 | } |
| 582 | rcu_read_unlock(); |
| 583 | |
| 584 | if (atomic_read(&bat_priv->fragmentation) == 0) |
| 585 | goto out; |
| 586 | |
| 587 | /* with fragmentation enabled the maximum size of internally generated |
| 588 | * packets such as translation table exchanges or tvlv containers, etc |
| 589 | * has to be calculated |
| 590 | */ |
| 591 | min_mtu = min_t(int, min_mtu, BATADV_FRAG_MAX_FRAG_SIZE); |
| 592 | min_mtu -= sizeof(struct batadv_frag_packet); |
| 593 | min_mtu *= BATADV_FRAG_MAX_FRAGMENTS; |
| 594 | |
| 595 | out: |
| 596 | /* report to the other components the maximum amount of bytes that |
| 597 | * batman-adv can send over the wire (without considering the payload |
| 598 | * overhead). For example, this value is used by TT to compute the |
| 599 | * maximum local table table size |
| 600 | */ |
| 601 | atomic_set(&bat_priv->packet_size_max, min_mtu); |
| 602 | |
| 603 | /* the real soft-interface MTU is computed by removing the payload |
| 604 | * overhead from the maximum amount of bytes that was just computed. |
| 605 | * |
| 606 | * However batman-adv does not support MTUs bigger than ETH_DATA_LEN |
| 607 | */ |
| 608 | return min_t(int, min_mtu - batadv_max_header_len(), ETH_DATA_LEN); |
| 609 | } |
| 610 | |
| 611 | /* adjusts the MTU if a new interface with a smaller MTU appeared. */ |
| 612 | void batadv_update_min_mtu(struct net_device *soft_iface) |
| 613 | { |
| 614 | soft_iface->mtu = batadv_hardif_min_mtu(soft_iface); |
| 615 | |
| 616 | /* Check if the local translate table should be cleaned up to match a |
| 617 | * new (and smaller) MTU. |
| 618 | */ |
| 619 | batadv_tt_local_resize_to_mtu(soft_iface); |
| 620 | } |
| 621 | |
| 622 | static void |
| 623 | batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface) |
| 624 | { |
| 625 | struct batadv_priv *bat_priv; |
| 626 | struct batadv_hard_iface *primary_if = NULL; |
| 627 | |
| 628 | if (hard_iface->if_status != BATADV_IF_INACTIVE) |
| 629 | goto out; |
| 630 | |
| 631 | bat_priv = netdev_priv(hard_iface->soft_iface); |
| 632 | |
| 633 | bat_priv->algo_ops->iface.update_mac(hard_iface); |
| 634 | hard_iface->if_status = BATADV_IF_TO_BE_ACTIVATED; |
| 635 | |
| 636 | /* the first active interface becomes our primary interface or |
| 637 | * the next active interface after the old primary interface was removed |
| 638 | */ |
| 639 | primary_if = batadv_primary_if_get_selected(bat_priv); |
| 640 | if (!primary_if) |
| 641 | batadv_primary_if_select(bat_priv, hard_iface); |
| 642 | |
| 643 | batadv_info(hard_iface->soft_iface, "Interface activated: %s\n", |
| 644 | hard_iface->net_dev->name); |
| 645 | |
| 646 | batadv_update_min_mtu(hard_iface->soft_iface); |
| 647 | |
| 648 | if (bat_priv->algo_ops->iface.activate) |
| 649 | bat_priv->algo_ops->iface.activate(hard_iface); |
| 650 | |
| 651 | out: |
| 652 | if (primary_if) |
| 653 | batadv_hardif_put(primary_if); |
| 654 | } |
| 655 | |
| 656 | static void |
| 657 | batadv_hardif_deactivate_interface(struct batadv_hard_iface *hard_iface) |
| 658 | { |
| 659 | if ((hard_iface->if_status != BATADV_IF_ACTIVE) && |
| 660 | (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED)) |
| 661 | return; |
| 662 | |
| 663 | hard_iface->if_status = BATADV_IF_INACTIVE; |
| 664 | |
| 665 | batadv_info(hard_iface->soft_iface, "Interface deactivated: %s\n", |
| 666 | hard_iface->net_dev->name); |
| 667 | |
| 668 | batadv_update_min_mtu(hard_iface->soft_iface); |
| 669 | } |
| 670 | |
| 671 | /** |
| 672 | * batadv_master_del_slave - remove hard_iface from the current master interface |
| 673 | * @slave: the interface enslaved in another master |
| 674 | * @master: the master from which slave has to be removed |
| 675 | * |
| 676 | * Invoke ndo_del_slave on master passing slave as argument. In this way slave |
| 677 | * is free'd and master can correctly change its internal state. |
| 678 | * |
| 679 | * Return: 0 on success, a negative value representing the error otherwise |
| 680 | */ |
| 681 | static int batadv_master_del_slave(struct batadv_hard_iface *slave, |
| 682 | struct net_device *master) |
| 683 | { |
| 684 | int ret; |
| 685 | |
| 686 | if (!master) |
| 687 | return 0; |
| 688 | |
| 689 | ret = -EBUSY; |
| 690 | if (master->netdev_ops->ndo_del_slave) |
| 691 | ret = master->netdev_ops->ndo_del_slave(master, slave->net_dev); |
| 692 | |
| 693 | return ret; |
| 694 | } |
| 695 | |
| 696 | int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface, |
| 697 | struct net *net, const char *iface_name) |
| 698 | { |
| 699 | struct batadv_priv *bat_priv; |
| 700 | struct net_device *soft_iface, *master; |
| 701 | __be16 ethertype = htons(ETH_P_BATMAN); |
| 702 | int max_header_len = batadv_max_header_len(); |
| 703 | int ret; |
| 704 | |
| 705 | if (hard_iface->if_status != BATADV_IF_NOT_IN_USE) |
| 706 | goto out; |
| 707 | |
| 708 | kref_get(&hard_iface->refcount); |
| 709 | |
| 710 | soft_iface = dev_get_by_name(net, iface_name); |
| 711 | |
| 712 | if (!soft_iface) { |
| 713 | soft_iface = batadv_softif_create(net, iface_name); |
| 714 | |
| 715 | if (!soft_iface) { |
| 716 | ret = -ENOMEM; |
| 717 | goto err; |
| 718 | } |
| 719 | |
| 720 | /* dev_get_by_name() increases the reference counter for us */ |
| 721 | dev_hold(soft_iface); |
| 722 | } |
| 723 | |
| 724 | if (!batadv_softif_is_valid(soft_iface)) { |
| 725 | pr_err("Can't create batman mesh interface %s: already exists as regular interface\n", |
| 726 | soft_iface->name); |
| 727 | ret = -EINVAL; |
| 728 | goto err_dev; |
| 729 | } |
| 730 | |
| 731 | /* check if the interface is enslaved in another virtual one and |
| 732 | * in that case unlink it first |
| 733 | */ |
| 734 | master = netdev_master_upper_dev_get(hard_iface->net_dev); |
| 735 | ret = batadv_master_del_slave(hard_iface, master); |
| 736 | if (ret) |
| 737 | goto err_dev; |
| 738 | |
| 739 | hard_iface->soft_iface = soft_iface; |
| 740 | bat_priv = netdev_priv(hard_iface->soft_iface); |
| 741 | |
| 742 | if (bat_priv->num_ifaces >= UINT_MAX) { |
| 743 | ret = -ENOSPC; |
| 744 | goto err_dev; |
| 745 | } |
| 746 | |
| 747 | ret = netdev_master_upper_dev_link(hard_iface->net_dev, |
| 748 | soft_iface, NULL, NULL); |
| 749 | if (ret) |
| 750 | goto err_dev; |
| 751 | |
| 752 | ret = bat_priv->algo_ops->iface.enable(hard_iface); |
| 753 | if (ret < 0) |
| 754 | goto err_upper; |
| 755 | |
| 756 | hard_iface->if_num = bat_priv->num_ifaces; |
| 757 | bat_priv->num_ifaces++; |
| 758 | hard_iface->if_status = BATADV_IF_INACTIVE; |
| 759 | ret = batadv_orig_hash_add_if(hard_iface, bat_priv->num_ifaces); |
| 760 | if (ret < 0) { |
| 761 | bat_priv->algo_ops->iface.disable(hard_iface); |
| 762 | bat_priv->num_ifaces--; |
| 763 | hard_iface->if_status = BATADV_IF_NOT_IN_USE; |
| 764 | goto err_upper; |
| 765 | } |
| 766 | |
| 767 | kref_get(&hard_iface->refcount); |
| 768 | hard_iface->batman_adv_ptype.type = ethertype; |
| 769 | hard_iface->batman_adv_ptype.func = batadv_batman_skb_recv; |
| 770 | hard_iface->batman_adv_ptype.dev = hard_iface->net_dev; |
| 771 | dev_add_pack(&hard_iface->batman_adv_ptype); |
| 772 | |
| 773 | batadv_info(hard_iface->soft_iface, "Adding interface: %s\n", |
| 774 | hard_iface->net_dev->name); |
| 775 | |
| 776 | if (atomic_read(&bat_priv->fragmentation) && |
| 777 | hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len) |
| 778 | batadv_info(hard_iface->soft_iface, |
| 779 | "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", |
| 780 | hard_iface->net_dev->name, hard_iface->net_dev->mtu, |
| 781 | ETH_DATA_LEN + max_header_len); |
| 782 | |
| 783 | if (!atomic_read(&bat_priv->fragmentation) && |
| 784 | hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len) |
| 785 | batadv_info(hard_iface->soft_iface, |
| 786 | "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", |
| 787 | hard_iface->net_dev->name, hard_iface->net_dev->mtu, |
| 788 | ETH_DATA_LEN + max_header_len); |
| 789 | |
| 790 | if (batadv_hardif_is_iface_up(hard_iface)) |
| 791 | batadv_hardif_activate_interface(hard_iface); |
| 792 | else |
| 793 | batadv_err(hard_iface->soft_iface, |
| 794 | "Not using interface %s (retrying later): interface not active\n", |
| 795 | hard_iface->net_dev->name); |
| 796 | |
| 797 | batadv_hardif_recalc_extra_skbroom(soft_iface); |
| 798 | |
| 799 | if (bat_priv->algo_ops->iface.enabled) |
| 800 | bat_priv->algo_ops->iface.enabled(hard_iface); |
| 801 | |
| 802 | out: |
| 803 | return 0; |
| 804 | |
| 805 | err_upper: |
| 806 | netdev_upper_dev_unlink(hard_iface->net_dev, soft_iface); |
| 807 | err_dev: |
| 808 | hard_iface->soft_iface = NULL; |
| 809 | dev_put(soft_iface); |
| 810 | err: |
| 811 | batadv_hardif_put(hard_iface); |
| 812 | return ret; |
| 813 | } |
| 814 | |
| 815 | void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface, |
| 816 | enum batadv_hard_if_cleanup autodel) |
| 817 | { |
| 818 | struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface); |
| 819 | struct batadv_hard_iface *primary_if = NULL; |
| 820 | |
| 821 | batadv_hardif_deactivate_interface(hard_iface); |
| 822 | |
| 823 | if (hard_iface->if_status != BATADV_IF_INACTIVE) |
| 824 | goto out; |
| 825 | |
| 826 | batadv_info(hard_iface->soft_iface, "Removing interface: %s\n", |
| 827 | hard_iface->net_dev->name); |
| 828 | dev_remove_pack(&hard_iface->batman_adv_ptype); |
| 829 | batadv_hardif_put(hard_iface); |
| 830 | |
| 831 | bat_priv->num_ifaces--; |
| 832 | batadv_orig_hash_del_if(hard_iface, bat_priv->num_ifaces); |
| 833 | |
| 834 | primary_if = batadv_primary_if_get_selected(bat_priv); |
| 835 | if (hard_iface == primary_if) { |
| 836 | struct batadv_hard_iface *new_if; |
| 837 | |
| 838 | new_if = batadv_hardif_get_active(hard_iface->soft_iface); |
| 839 | batadv_primary_if_select(bat_priv, new_if); |
| 840 | |
| 841 | if (new_if) |
| 842 | batadv_hardif_put(new_if); |
| 843 | } |
| 844 | |
| 845 | bat_priv->algo_ops->iface.disable(hard_iface); |
| 846 | hard_iface->if_status = BATADV_IF_NOT_IN_USE; |
| 847 | |
| 848 | /* delete all references to this hard_iface */ |
| 849 | batadv_purge_orig_ref(bat_priv); |
| 850 | batadv_purge_outstanding_packets(bat_priv, hard_iface); |
| 851 | dev_put(hard_iface->soft_iface); |
| 852 | |
| 853 | netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface); |
| 854 | batadv_hardif_recalc_extra_skbroom(hard_iface->soft_iface); |
| 855 | |
| 856 | /* nobody uses this interface anymore */ |
| 857 | if (bat_priv->num_ifaces == 0) { |
| 858 | batadv_gw_check_client_stop(bat_priv); |
| 859 | |
| 860 | if (autodel == BATADV_IF_CLEANUP_AUTO) |
| 861 | batadv_softif_destroy_sysfs(hard_iface->soft_iface); |
| 862 | } |
| 863 | |
| 864 | hard_iface->soft_iface = NULL; |
| 865 | batadv_hardif_put(hard_iface); |
| 866 | |
| 867 | out: |
| 868 | if (primary_if) |
| 869 | batadv_hardif_put(primary_if); |
| 870 | } |
| 871 | |
| 872 | static struct batadv_hard_iface * |
| 873 | batadv_hardif_add_interface(struct net_device *net_dev) |
| 874 | { |
| 875 | struct batadv_hard_iface *hard_iface; |
| 876 | int ret; |
| 877 | |
| 878 | ASSERT_RTNL(); |
| 879 | |
| 880 | if (!batadv_is_valid_iface(net_dev)) |
| 881 | goto out; |
| 882 | |
| 883 | dev_hold(net_dev); |
| 884 | |
| 885 | hard_iface = kzalloc(sizeof(*hard_iface), GFP_ATOMIC); |
| 886 | if (!hard_iface) |
| 887 | goto release_dev; |
| 888 | |
| 889 | ret = batadv_sysfs_add_hardif(&hard_iface->hardif_obj, net_dev); |
| 890 | if (ret) |
| 891 | goto free_if; |
| 892 | |
| 893 | hard_iface->if_num = 0; |
| 894 | hard_iface->net_dev = net_dev; |
| 895 | hard_iface->soft_iface = NULL; |
| 896 | hard_iface->if_status = BATADV_IF_NOT_IN_USE; |
| 897 | |
| 898 | ret = batadv_debugfs_add_hardif(hard_iface); |
| 899 | if (ret) |
| 900 | goto free_sysfs; |
| 901 | |
| 902 | INIT_LIST_HEAD(&hard_iface->list); |
| 903 | INIT_HLIST_HEAD(&hard_iface->neigh_list); |
| 904 | |
| 905 | mutex_init(&hard_iface->bat_iv.ogm_buff_mutex); |
| 906 | spin_lock_init(&hard_iface->neigh_list_lock); |
| 907 | kref_init(&hard_iface->refcount); |
| 908 | |
| 909 | hard_iface->num_bcasts = BATADV_NUM_BCASTS_DEFAULT; |
| 910 | hard_iface->wifi_flags = batadv_wifi_flags_evaluate(net_dev); |
| 911 | if (batadv_is_wifi_hardif(hard_iface)) |
| 912 | hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS; |
| 913 | |
| 914 | batadv_v_hardif_init(hard_iface); |
| 915 | |
| 916 | batadv_check_known_mac_addr(hard_iface->net_dev); |
| 917 | kref_get(&hard_iface->refcount); |
| 918 | list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list); |
| 919 | |
| 920 | return hard_iface; |
| 921 | |
| 922 | free_sysfs: |
| 923 | batadv_sysfs_del_hardif(&hard_iface->hardif_obj); |
| 924 | free_if: |
| 925 | kfree(hard_iface); |
| 926 | release_dev: |
| 927 | dev_put(net_dev); |
| 928 | out: |
| 929 | return NULL; |
| 930 | } |
| 931 | |
| 932 | static void batadv_hardif_remove_interface(struct batadv_hard_iface *hard_iface) |
| 933 | { |
| 934 | ASSERT_RTNL(); |
| 935 | |
| 936 | /* first deactivate interface */ |
| 937 | if (hard_iface->if_status != BATADV_IF_NOT_IN_USE) |
| 938 | batadv_hardif_disable_interface(hard_iface, |
| 939 | BATADV_IF_CLEANUP_KEEP); |
| 940 | |
| 941 | if (hard_iface->if_status != BATADV_IF_NOT_IN_USE) |
| 942 | return; |
| 943 | |
| 944 | hard_iface->if_status = BATADV_IF_TO_BE_REMOVED; |
| 945 | batadv_debugfs_del_hardif(hard_iface); |
| 946 | batadv_sysfs_del_hardif(&hard_iface->hardif_obj); |
| 947 | batadv_hardif_put(hard_iface); |
| 948 | } |
| 949 | |
| 950 | void batadv_hardif_remove_interfaces(void) |
| 951 | { |
| 952 | struct batadv_hard_iface *hard_iface, *hard_iface_tmp; |
| 953 | |
| 954 | rtnl_lock(); |
| 955 | list_for_each_entry_safe(hard_iface, hard_iface_tmp, |
| 956 | &batadv_hardif_list, list) { |
| 957 | list_del_rcu(&hard_iface->list); |
| 958 | batadv_hardif_remove_interface(hard_iface); |
| 959 | } |
| 960 | rtnl_unlock(); |
| 961 | } |
| 962 | |
| 963 | /** |
| 964 | * batadv_hard_if_event_softif() - Handle events for soft interfaces |
| 965 | * @event: NETDEV_* event to handle |
| 966 | * @net_dev: net_device which generated an event |
| 967 | * |
| 968 | * Return: NOTIFY_* result |
| 969 | */ |
| 970 | static int batadv_hard_if_event_softif(unsigned long event, |
| 971 | struct net_device *net_dev) |
| 972 | { |
| 973 | struct batadv_priv *bat_priv; |
| 974 | |
| 975 | switch (event) { |
| 976 | case NETDEV_REGISTER: |
| 977 | batadv_sysfs_add_meshif(net_dev); |
| 978 | bat_priv = netdev_priv(net_dev); |
| 979 | batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS); |
| 980 | break; |
| 981 | case NETDEV_CHANGENAME: |
| 982 | batadv_debugfs_rename_meshif(net_dev); |
| 983 | break; |
| 984 | } |
| 985 | |
| 986 | return NOTIFY_DONE; |
| 987 | } |
| 988 | |
| 989 | static int batadv_hard_if_event(struct notifier_block *this, |
| 990 | unsigned long event, void *ptr) |
| 991 | { |
| 992 | struct net_device *net_dev = netdev_notifier_info_to_dev(ptr); |
| 993 | struct batadv_hard_iface *hard_iface; |
| 994 | struct batadv_hard_iface *primary_if = NULL; |
| 995 | struct batadv_priv *bat_priv; |
| 996 | |
| 997 | if (batadv_softif_is_valid(net_dev)) |
| 998 | return batadv_hard_if_event_softif(event, net_dev); |
| 999 | |
| 1000 | hard_iface = batadv_hardif_get_by_netdev(net_dev); |
| 1001 | if (!hard_iface && (event == NETDEV_REGISTER || |
| 1002 | event == NETDEV_POST_TYPE_CHANGE)) |
| 1003 | hard_iface = batadv_hardif_add_interface(net_dev); |
| 1004 | |
| 1005 | if (!hard_iface) |
| 1006 | goto out; |
| 1007 | |
| 1008 | switch (event) { |
| 1009 | case NETDEV_UP: |
| 1010 | batadv_hardif_activate_interface(hard_iface); |
| 1011 | break; |
| 1012 | case NETDEV_GOING_DOWN: |
| 1013 | case NETDEV_DOWN: |
| 1014 | batadv_hardif_deactivate_interface(hard_iface); |
| 1015 | break; |
| 1016 | case NETDEV_UNREGISTER: |
| 1017 | case NETDEV_PRE_TYPE_CHANGE: |
| 1018 | list_del_rcu(&hard_iface->list); |
| 1019 | |
| 1020 | batadv_hardif_remove_interface(hard_iface); |
| 1021 | break; |
| 1022 | case NETDEV_CHANGEMTU: |
| 1023 | if (hard_iface->soft_iface) |
| 1024 | batadv_update_min_mtu(hard_iface->soft_iface); |
| 1025 | break; |
| 1026 | case NETDEV_CHANGEADDR: |
| 1027 | if (hard_iface->if_status == BATADV_IF_NOT_IN_USE) |
| 1028 | goto hardif_put; |
| 1029 | |
| 1030 | batadv_check_known_mac_addr(hard_iface->net_dev); |
| 1031 | |
| 1032 | bat_priv = netdev_priv(hard_iface->soft_iface); |
| 1033 | bat_priv->algo_ops->iface.update_mac(hard_iface); |
| 1034 | |
| 1035 | primary_if = batadv_primary_if_get_selected(bat_priv); |
| 1036 | if (!primary_if) |
| 1037 | goto hardif_put; |
| 1038 | |
| 1039 | if (hard_iface == primary_if) |
| 1040 | batadv_primary_if_update_addr(bat_priv, NULL); |
| 1041 | break; |
| 1042 | case NETDEV_CHANGEUPPER: |
| 1043 | hard_iface->wifi_flags = batadv_wifi_flags_evaluate(net_dev); |
| 1044 | if (batadv_is_wifi_hardif(hard_iface)) |
| 1045 | hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS; |
| 1046 | break; |
| 1047 | case NETDEV_CHANGENAME: |
| 1048 | batadv_debugfs_rename_hardif(hard_iface); |
| 1049 | break; |
| 1050 | default: |
| 1051 | break; |
| 1052 | } |
| 1053 | |
| 1054 | hardif_put: |
| 1055 | batadv_hardif_put(hard_iface); |
| 1056 | out: |
| 1057 | if (primary_if) |
| 1058 | batadv_hardif_put(primary_if); |
| 1059 | return NOTIFY_DONE; |
| 1060 | } |
| 1061 | |
| 1062 | struct notifier_block batadv_hard_if_notifier = { |
| 1063 | .notifier_call = batadv_hard_if_event, |
| 1064 | }; |