fix a kmap leak in virtio_console
[linux/fpc-iii.git] / net / batman-adv / hard-interface.c
blob3d417d3641c6d83a4ecb4f87bdf48d4f26d48242
1 /* Copyright (C) 2007-2014 B.A.T.M.A.N. contributors:
3 * Marek Lindner, Simon Wunderlich
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.
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.
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/>.
18 #include "main.h"
19 #include "distributed-arp-table.h"
20 #include "hard-interface.h"
21 #include "soft-interface.h"
22 #include "send.h"
23 #include "translation-table.h"
24 #include "routing.h"
25 #include "sysfs.h"
26 #include "debugfs.h"
27 #include "originator.h"
28 #include "hash.h"
29 #include "bridge_loop_avoidance.h"
30 #include "gateway_client.h"
32 #include <linux/if_arp.h>
33 #include <linux/if_ether.h>
35 void batadv_hardif_free_rcu(struct rcu_head *rcu)
37 struct batadv_hard_iface *hard_iface;
39 hard_iface = container_of(rcu, struct batadv_hard_iface, rcu);
40 dev_put(hard_iface->net_dev);
41 kfree(hard_iface);
44 struct batadv_hard_iface *
45 batadv_hardif_get_by_netdev(const struct net_device *net_dev)
47 struct batadv_hard_iface *hard_iface;
49 rcu_read_lock();
50 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
51 if (hard_iface->net_dev == net_dev &&
52 atomic_inc_not_zero(&hard_iface->refcount))
53 goto out;
56 hard_iface = NULL;
58 out:
59 rcu_read_unlock();
60 return hard_iface;
63 /**
64 * batadv_is_on_batman_iface - check if a device is a batman iface descendant
65 * @net_dev: the device to check
67 * If the user creates any virtual device on top of a batman-adv interface, it
68 * is important to prevent this new interface to be used to create a new mesh
69 * network (this behaviour would lead to a batman-over-batman configuration).
70 * This function recursively checks all the fathers of the device passed as
71 * argument looking for a batman-adv soft interface.
73 * Returns true if the device is descendant of a batman-adv mesh interface (or
74 * if it is a batman-adv interface itself), false otherwise
76 static bool batadv_is_on_batman_iface(const struct net_device *net_dev)
78 struct net_device *parent_dev;
79 bool ret;
81 /* check if this is a batman-adv mesh interface */
82 if (batadv_softif_is_valid(net_dev))
83 return true;
85 /* no more parents..stop recursion */
86 if (net_dev->iflink == net_dev->ifindex)
87 return false;
89 /* recurse over the parent device */
90 parent_dev = __dev_get_by_index(&init_net, net_dev->iflink);
91 /* if we got a NULL parent_dev there is something broken.. */
92 if (WARN(!parent_dev, "Cannot find parent device"))
93 return false;
95 ret = batadv_is_on_batman_iface(parent_dev);
97 return ret;
100 static int batadv_is_valid_iface(const struct net_device *net_dev)
102 if (net_dev->flags & IFF_LOOPBACK)
103 return 0;
105 if (net_dev->type != ARPHRD_ETHER)
106 return 0;
108 if (net_dev->addr_len != ETH_ALEN)
109 return 0;
111 /* no batman over batman */
112 if (batadv_is_on_batman_iface(net_dev))
113 return 0;
115 return 1;
119 * batadv_is_wifi_netdev - check if the given net_device struct is a wifi
120 * interface
121 * @net_device: the device to check
123 * Returns true if the net device is a 802.11 wireless device, false otherwise.
125 bool batadv_is_wifi_netdev(struct net_device *net_device)
127 if (!net_device)
128 return false;
130 #ifdef CONFIG_WIRELESS_EXT
131 /* pre-cfg80211 drivers have to implement WEXT, so it is possible to
132 * check for wireless_handlers != NULL
134 if (net_device->wireless_handlers)
135 return true;
136 #endif
138 /* cfg80211 drivers have to set ieee80211_ptr */
139 if (net_device->ieee80211_ptr)
140 return true;
142 return false;
145 static struct batadv_hard_iface *
146 batadv_hardif_get_active(const struct net_device *soft_iface)
148 struct batadv_hard_iface *hard_iface;
150 rcu_read_lock();
151 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
152 if (hard_iface->soft_iface != soft_iface)
153 continue;
155 if (hard_iface->if_status == BATADV_IF_ACTIVE &&
156 atomic_inc_not_zero(&hard_iface->refcount))
157 goto out;
160 hard_iface = NULL;
162 out:
163 rcu_read_unlock();
164 return hard_iface;
167 static void batadv_primary_if_update_addr(struct batadv_priv *bat_priv,
168 struct batadv_hard_iface *oldif)
170 struct batadv_hard_iface *primary_if;
172 primary_if = batadv_primary_if_get_selected(bat_priv);
173 if (!primary_if)
174 goto out;
176 batadv_dat_init_own_addr(bat_priv, primary_if);
177 batadv_bla_update_orig_address(bat_priv, primary_if, oldif);
178 out:
179 if (primary_if)
180 batadv_hardif_free_ref(primary_if);
183 static void batadv_primary_if_select(struct batadv_priv *bat_priv,
184 struct batadv_hard_iface *new_hard_iface)
186 struct batadv_hard_iface *curr_hard_iface;
188 ASSERT_RTNL();
190 if (new_hard_iface && !atomic_inc_not_zero(&new_hard_iface->refcount))
191 new_hard_iface = NULL;
193 curr_hard_iface = rcu_dereference_protected(bat_priv->primary_if, 1);
194 rcu_assign_pointer(bat_priv->primary_if, new_hard_iface);
196 if (!new_hard_iface)
197 goto out;
199 bat_priv->bat_algo_ops->bat_primary_iface_set(new_hard_iface);
200 batadv_primary_if_update_addr(bat_priv, curr_hard_iface);
202 out:
203 if (curr_hard_iface)
204 batadv_hardif_free_ref(curr_hard_iface);
207 static bool
208 batadv_hardif_is_iface_up(const struct batadv_hard_iface *hard_iface)
210 if (hard_iface->net_dev->flags & IFF_UP)
211 return true;
213 return false;
216 static void batadv_check_known_mac_addr(const struct net_device *net_dev)
218 const struct batadv_hard_iface *hard_iface;
220 rcu_read_lock();
221 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
222 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
223 (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
224 continue;
226 if (hard_iface->net_dev == net_dev)
227 continue;
229 if (!batadv_compare_eth(hard_iface->net_dev->dev_addr,
230 net_dev->dev_addr))
231 continue;
233 pr_warn("The newly added mac address (%pM) already exists on: %s\n",
234 net_dev->dev_addr, hard_iface->net_dev->name);
235 pr_warn("It is strongly recommended to keep mac addresses unique to avoid problems!\n");
237 rcu_read_unlock();
240 int batadv_hardif_min_mtu(struct net_device *soft_iface)
242 struct batadv_priv *bat_priv = netdev_priv(soft_iface);
243 const struct batadv_hard_iface *hard_iface;
244 int min_mtu = ETH_DATA_LEN;
246 rcu_read_lock();
247 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
248 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
249 (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
250 continue;
252 if (hard_iface->soft_iface != soft_iface)
253 continue;
255 min_mtu = min_t(int, hard_iface->net_dev->mtu, min_mtu);
257 rcu_read_unlock();
259 atomic_set(&bat_priv->packet_size_max, min_mtu);
261 if (atomic_read(&bat_priv->fragmentation) == 0)
262 goto out;
264 /* with fragmentation enabled the maximum size of internally generated
265 * packets such as translation table exchanges or tvlv containers, etc
266 * has to be calculated
268 min_mtu = min_t(int, min_mtu, BATADV_FRAG_MAX_FRAG_SIZE);
269 min_mtu -= sizeof(struct batadv_frag_packet);
270 min_mtu *= BATADV_FRAG_MAX_FRAGMENTS;
271 atomic_set(&bat_priv->packet_size_max, min_mtu);
273 /* with fragmentation enabled we can fragment external packets easily */
274 min_mtu = min_t(int, min_mtu, ETH_DATA_LEN);
276 out:
277 return min_mtu - batadv_max_header_len();
280 /* adjusts the MTU if a new interface with a smaller MTU appeared. */
281 void batadv_update_min_mtu(struct net_device *soft_iface)
283 soft_iface->mtu = batadv_hardif_min_mtu(soft_iface);
285 /* Check if the local translate table should be cleaned up to match a
286 * new (and smaller) MTU.
288 batadv_tt_local_resize_to_mtu(soft_iface);
291 static void
292 batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface)
294 struct batadv_priv *bat_priv;
295 struct batadv_hard_iface *primary_if = NULL;
297 if (hard_iface->if_status != BATADV_IF_INACTIVE)
298 goto out;
300 bat_priv = netdev_priv(hard_iface->soft_iface);
302 bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
303 hard_iface->if_status = BATADV_IF_TO_BE_ACTIVATED;
305 /* the first active interface becomes our primary interface or
306 * the next active interface after the old primary interface was removed
308 primary_if = batadv_primary_if_get_selected(bat_priv);
309 if (!primary_if)
310 batadv_primary_if_select(bat_priv, hard_iface);
312 batadv_info(hard_iface->soft_iface, "Interface activated: %s\n",
313 hard_iface->net_dev->name);
315 batadv_update_min_mtu(hard_iface->soft_iface);
317 out:
318 if (primary_if)
319 batadv_hardif_free_ref(primary_if);
322 static void
323 batadv_hardif_deactivate_interface(struct batadv_hard_iface *hard_iface)
325 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
326 (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
327 return;
329 hard_iface->if_status = BATADV_IF_INACTIVE;
331 batadv_info(hard_iface->soft_iface, "Interface deactivated: %s\n",
332 hard_iface->net_dev->name);
334 batadv_update_min_mtu(hard_iface->soft_iface);
338 * batadv_master_del_slave - remove hard_iface from the current master interface
339 * @slave: the interface enslaved in another master
340 * @master: the master from which slave has to be removed
342 * Invoke ndo_del_slave on master passing slave as argument. In this way slave
343 * is free'd and master can correctly change its internal state.
344 * Return 0 on success, a negative value representing the error otherwise
346 static int batadv_master_del_slave(struct batadv_hard_iface *slave,
347 struct net_device *master)
349 int ret;
351 if (!master)
352 return 0;
354 ret = -EBUSY;
355 if (master->netdev_ops->ndo_del_slave)
356 ret = master->netdev_ops->ndo_del_slave(master, slave->net_dev);
358 return ret;
361 int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
362 const char *iface_name)
364 struct batadv_priv *bat_priv;
365 struct net_device *soft_iface, *master;
366 __be16 ethertype = htons(ETH_P_BATMAN);
367 int max_header_len = batadv_max_header_len();
368 int ret;
370 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
371 goto out;
373 if (!atomic_inc_not_zero(&hard_iface->refcount))
374 goto out;
376 soft_iface = dev_get_by_name(&init_net, iface_name);
378 if (!soft_iface) {
379 soft_iface = batadv_softif_create(iface_name);
381 if (!soft_iface) {
382 ret = -ENOMEM;
383 goto err;
386 /* dev_get_by_name() increases the reference counter for us */
387 dev_hold(soft_iface);
390 if (!batadv_softif_is_valid(soft_iface)) {
391 pr_err("Can't create batman mesh interface %s: already exists as regular interface\n",
392 soft_iface->name);
393 ret = -EINVAL;
394 goto err_dev;
397 /* check if the interface is enslaved in another virtual one and
398 * in that case unlink it first
400 master = netdev_master_upper_dev_get(hard_iface->net_dev);
401 ret = batadv_master_del_slave(hard_iface, master);
402 if (ret)
403 goto err_dev;
405 hard_iface->soft_iface = soft_iface;
406 bat_priv = netdev_priv(hard_iface->soft_iface);
408 ret = netdev_master_upper_dev_link(hard_iface->net_dev, soft_iface);
409 if (ret)
410 goto err_dev;
412 ret = bat_priv->bat_algo_ops->bat_iface_enable(hard_iface);
413 if (ret < 0)
414 goto err_upper;
416 hard_iface->if_num = bat_priv->num_ifaces;
417 bat_priv->num_ifaces++;
418 hard_iface->if_status = BATADV_IF_INACTIVE;
419 ret = batadv_orig_hash_add_if(hard_iface, bat_priv->num_ifaces);
420 if (ret < 0) {
421 bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
422 bat_priv->num_ifaces--;
423 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
424 goto err_upper;
427 hard_iface->batman_adv_ptype.type = ethertype;
428 hard_iface->batman_adv_ptype.func = batadv_batman_skb_recv;
429 hard_iface->batman_adv_ptype.dev = hard_iface->net_dev;
430 dev_add_pack(&hard_iface->batman_adv_ptype);
432 batadv_info(hard_iface->soft_iface, "Adding interface: %s\n",
433 hard_iface->net_dev->name);
435 if (atomic_read(&bat_priv->fragmentation) &&
436 hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
437 batadv_info(hard_iface->soft_iface,
438 "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",
439 hard_iface->net_dev->name, hard_iface->net_dev->mtu,
440 ETH_DATA_LEN + max_header_len);
442 if (!atomic_read(&bat_priv->fragmentation) &&
443 hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
444 batadv_info(hard_iface->soft_iface,
445 "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",
446 hard_iface->net_dev->name, hard_iface->net_dev->mtu,
447 ETH_DATA_LEN + max_header_len);
449 if (batadv_hardif_is_iface_up(hard_iface))
450 batadv_hardif_activate_interface(hard_iface);
451 else
452 batadv_err(hard_iface->soft_iface,
453 "Not using interface %s (retrying later): interface not active\n",
454 hard_iface->net_dev->name);
456 /* begin scheduling originator messages on that interface */
457 batadv_schedule_bat_ogm(hard_iface);
459 out:
460 return 0;
462 err_upper:
463 netdev_upper_dev_unlink(hard_iface->net_dev, soft_iface);
464 err_dev:
465 hard_iface->soft_iface = NULL;
466 dev_put(soft_iface);
467 err:
468 batadv_hardif_free_ref(hard_iface);
469 return ret;
472 void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
473 enum batadv_hard_if_cleanup autodel)
475 struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
476 struct batadv_hard_iface *primary_if = NULL;
478 if (hard_iface->if_status == BATADV_IF_ACTIVE)
479 batadv_hardif_deactivate_interface(hard_iface);
481 if (hard_iface->if_status != BATADV_IF_INACTIVE)
482 goto out;
484 batadv_info(hard_iface->soft_iface, "Removing interface: %s\n",
485 hard_iface->net_dev->name);
486 dev_remove_pack(&hard_iface->batman_adv_ptype);
488 bat_priv->num_ifaces--;
489 batadv_orig_hash_del_if(hard_iface, bat_priv->num_ifaces);
491 primary_if = batadv_primary_if_get_selected(bat_priv);
492 if (hard_iface == primary_if) {
493 struct batadv_hard_iface *new_if;
495 new_if = batadv_hardif_get_active(hard_iface->soft_iface);
496 batadv_primary_if_select(bat_priv, new_if);
498 if (new_if)
499 batadv_hardif_free_ref(new_if);
502 bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
503 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
505 /* delete all references to this hard_iface */
506 batadv_purge_orig_ref(bat_priv);
507 batadv_purge_outstanding_packets(bat_priv, hard_iface);
508 dev_put(hard_iface->soft_iface);
510 /* nobody uses this interface anymore */
511 if (!bat_priv->num_ifaces) {
512 batadv_gw_check_client_stop(bat_priv);
514 if (autodel == BATADV_IF_CLEANUP_AUTO)
515 batadv_softif_destroy_sysfs(hard_iface->soft_iface);
518 netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);
519 hard_iface->soft_iface = NULL;
520 batadv_hardif_free_ref(hard_iface);
522 out:
523 if (primary_if)
524 batadv_hardif_free_ref(primary_if);
528 * batadv_hardif_remove_interface_finish - cleans up the remains of a hardif
529 * @work: work queue item
531 * Free the parts of the hard interface which can not be removed under
532 * rtnl lock (to prevent deadlock situations).
534 static void batadv_hardif_remove_interface_finish(struct work_struct *work)
536 struct batadv_hard_iface *hard_iface;
538 hard_iface = container_of(work, struct batadv_hard_iface,
539 cleanup_work);
541 batadv_debugfs_del_hardif(hard_iface);
542 batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
543 batadv_hardif_free_ref(hard_iface);
546 static struct batadv_hard_iface *
547 batadv_hardif_add_interface(struct net_device *net_dev)
549 struct batadv_hard_iface *hard_iface;
550 int ret;
552 ASSERT_RTNL();
554 ret = batadv_is_valid_iface(net_dev);
555 if (ret != 1)
556 goto out;
558 dev_hold(net_dev);
560 hard_iface = kzalloc(sizeof(*hard_iface), GFP_ATOMIC);
561 if (!hard_iface)
562 goto release_dev;
564 ret = batadv_sysfs_add_hardif(&hard_iface->hardif_obj, net_dev);
565 if (ret)
566 goto free_if;
568 hard_iface->if_num = -1;
569 hard_iface->net_dev = net_dev;
570 hard_iface->soft_iface = NULL;
571 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
573 ret = batadv_debugfs_add_hardif(hard_iface);
574 if (ret)
575 goto free_sysfs;
577 INIT_LIST_HEAD(&hard_iface->list);
578 INIT_WORK(&hard_iface->cleanup_work,
579 batadv_hardif_remove_interface_finish);
581 hard_iface->num_bcasts = BATADV_NUM_BCASTS_DEFAULT;
582 if (batadv_is_wifi_netdev(net_dev))
583 hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS;
585 /* extra reference for return */
586 atomic_set(&hard_iface->refcount, 2);
588 batadv_check_known_mac_addr(hard_iface->net_dev);
589 list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);
591 return hard_iface;
593 free_sysfs:
594 batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
595 free_if:
596 kfree(hard_iface);
597 release_dev:
598 dev_put(net_dev);
599 out:
600 return NULL;
603 static void batadv_hardif_remove_interface(struct batadv_hard_iface *hard_iface)
605 ASSERT_RTNL();
607 /* first deactivate interface */
608 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
609 batadv_hardif_disable_interface(hard_iface,
610 BATADV_IF_CLEANUP_AUTO);
612 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
613 return;
615 hard_iface->if_status = BATADV_IF_TO_BE_REMOVED;
616 queue_work(batadv_event_workqueue, &hard_iface->cleanup_work);
619 void batadv_hardif_remove_interfaces(void)
621 struct batadv_hard_iface *hard_iface, *hard_iface_tmp;
623 rtnl_lock();
624 list_for_each_entry_safe(hard_iface, hard_iface_tmp,
625 &batadv_hardif_list, list) {
626 list_del_rcu(&hard_iface->list);
627 batadv_hardif_remove_interface(hard_iface);
629 rtnl_unlock();
632 static int batadv_hard_if_event(struct notifier_block *this,
633 unsigned long event, void *ptr)
635 struct net_device *net_dev = netdev_notifier_info_to_dev(ptr);
636 struct batadv_hard_iface *hard_iface;
637 struct batadv_hard_iface *primary_if = NULL;
638 struct batadv_priv *bat_priv;
640 if (batadv_softif_is_valid(net_dev) && event == NETDEV_REGISTER) {
641 batadv_sysfs_add_meshif(net_dev);
642 bat_priv = netdev_priv(net_dev);
643 batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS);
644 return NOTIFY_DONE;
647 hard_iface = batadv_hardif_get_by_netdev(net_dev);
648 if (!hard_iface && event == NETDEV_REGISTER)
649 hard_iface = batadv_hardif_add_interface(net_dev);
651 if (!hard_iface)
652 goto out;
654 switch (event) {
655 case NETDEV_UP:
656 batadv_hardif_activate_interface(hard_iface);
657 break;
658 case NETDEV_GOING_DOWN:
659 case NETDEV_DOWN:
660 batadv_hardif_deactivate_interface(hard_iface);
661 break;
662 case NETDEV_UNREGISTER:
663 list_del_rcu(&hard_iface->list);
665 batadv_hardif_remove_interface(hard_iface);
666 break;
667 case NETDEV_CHANGEMTU:
668 if (hard_iface->soft_iface)
669 batadv_update_min_mtu(hard_iface->soft_iface);
670 break;
671 case NETDEV_CHANGEADDR:
672 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
673 goto hardif_put;
675 batadv_check_known_mac_addr(hard_iface->net_dev);
677 bat_priv = netdev_priv(hard_iface->soft_iface);
678 bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
680 primary_if = batadv_primary_if_get_selected(bat_priv);
681 if (!primary_if)
682 goto hardif_put;
684 if (hard_iface == primary_if)
685 batadv_primary_if_update_addr(bat_priv, NULL);
686 break;
687 default:
688 break;
691 hardif_put:
692 batadv_hardif_free_ref(hard_iface);
693 out:
694 if (primary_if)
695 batadv_hardif_free_ref(primary_if);
696 return NOTIFY_DONE;
699 struct notifier_block batadv_hard_if_notifier = {
700 .notifier_call = batadv_hard_if_event,