1 /* Copyright (C) 2007-2015 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 "hard-interface.h"
21 #include <linux/bug.h>
22 #include <linux/byteorder/generic.h>
23 #include <linux/errno.h>
25 #include <linux/if_arp.h>
26 #include <linux/if_ether.h>
28 #include <linux/kernel.h>
29 #include <linux/list.h>
30 #include <linux/netdevice.h>
31 #include <linux/printk.h>
32 #include <linux/rculist.h>
33 #include <linux/rtnetlink.h>
34 #include <linux/slab.h>
35 #include <linux/workqueue.h>
36 #include <net/net_namespace.h>
38 #include "bridge_loop_avoidance.h"
40 #include "distributed-arp-table.h"
41 #include "gateway_client.h"
42 #include "originator.h"
45 #include "soft-interface.h"
47 #include "translation-table.h"
49 void batadv_hardif_free_rcu(struct rcu_head *rcu)
51 struct batadv_hard_iface *hard_iface;
53 hard_iface = container_of(rcu, struct batadv_hard_iface, rcu);
54 dev_put(hard_iface->net_dev);
58 struct batadv_hard_iface *
59 batadv_hardif_get_by_netdev(const struct net_device *net_dev)
61 struct batadv_hard_iface *hard_iface;
64 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
65 if (hard_iface->net_dev == net_dev &&
66 atomic_inc_not_zero(&hard_iface->refcount))
78 * batadv_is_on_batman_iface - check if a device is a batman iface descendant
79 * @net_dev: the device to check
81 * If the user creates any virtual device on top of a batman-adv interface, it
82 * is important to prevent this new interface to be used to create a new mesh
83 * network (this behaviour would lead to a batman-over-batman configuration).
84 * This function recursively checks all the fathers of the device passed as
85 * argument looking for a batman-adv soft interface.
87 * Returns true if the device is descendant of a batman-adv mesh interface (or
88 * if it is a batman-adv interface itself), false otherwise
90 static bool batadv_is_on_batman_iface(const struct net_device *net_dev)
92 struct net_device *parent_dev;
95 /* check if this is a batman-adv mesh interface */
96 if (batadv_softif_is_valid(net_dev))
99 /* no more parents..stop recursion */
100 if (dev_get_iflink(net_dev) == 0 ||
101 dev_get_iflink(net_dev) == net_dev->ifindex)
104 /* recurse over the parent device */
105 parent_dev = __dev_get_by_index(&init_net, dev_get_iflink(net_dev));
106 /* if we got a NULL parent_dev there is something broken.. */
107 if (WARN(!parent_dev, "Cannot find parent device"))
110 ret = batadv_is_on_batman_iface(parent_dev);
115 static int batadv_is_valid_iface(const struct net_device *net_dev)
117 if (net_dev->flags & IFF_LOOPBACK)
120 if (net_dev->type != ARPHRD_ETHER)
123 if (net_dev->addr_len != ETH_ALEN)
126 /* no batman over batman */
127 if (batadv_is_on_batman_iface(net_dev))
134 * batadv_is_wifi_netdev - check if the given net_device struct is a wifi
136 * @net_device: the device to check
138 * Returns true if the net device is a 802.11 wireless device, false otherwise.
140 bool batadv_is_wifi_netdev(struct net_device *net_device)
145 #ifdef CONFIG_WIRELESS_EXT
146 /* pre-cfg80211 drivers have to implement WEXT, so it is possible to
147 * check for wireless_handlers != NULL
149 if (net_device->wireless_handlers)
153 /* cfg80211 drivers have to set ieee80211_ptr */
154 if (net_device->ieee80211_ptr)
160 static struct batadv_hard_iface *
161 batadv_hardif_get_active(const struct net_device *soft_iface)
163 struct batadv_hard_iface *hard_iface;
166 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
167 if (hard_iface->soft_iface != soft_iface)
170 if (hard_iface->if_status == BATADV_IF_ACTIVE &&
171 atomic_inc_not_zero(&hard_iface->refcount))
182 static void batadv_primary_if_update_addr(struct batadv_priv *bat_priv,
183 struct batadv_hard_iface *oldif)
185 struct batadv_hard_iface *primary_if;
187 primary_if = batadv_primary_if_get_selected(bat_priv);
191 batadv_dat_init_own_addr(bat_priv, primary_if);
192 batadv_bla_update_orig_address(bat_priv, primary_if, oldif);
195 batadv_hardif_free_ref(primary_if);
198 static void batadv_primary_if_select(struct batadv_priv *bat_priv,
199 struct batadv_hard_iface *new_hard_iface)
201 struct batadv_hard_iface *curr_hard_iface;
205 if (new_hard_iface && !atomic_inc_not_zero(&new_hard_iface->refcount))
206 new_hard_iface = NULL;
208 curr_hard_iface = rcu_dereference_protected(bat_priv->primary_if, 1);
209 rcu_assign_pointer(bat_priv->primary_if, new_hard_iface);
214 bat_priv->bat_algo_ops->bat_primary_iface_set(new_hard_iface);
215 batadv_primary_if_update_addr(bat_priv, curr_hard_iface);
219 batadv_hardif_free_ref(curr_hard_iface);
223 batadv_hardif_is_iface_up(const struct batadv_hard_iface *hard_iface)
225 if (hard_iface->net_dev->flags & IFF_UP)
231 static void batadv_check_known_mac_addr(const struct net_device *net_dev)
233 const struct batadv_hard_iface *hard_iface;
236 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
237 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
238 (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
241 if (hard_iface->net_dev == net_dev)
244 if (!batadv_compare_eth(hard_iface->net_dev->dev_addr,
248 pr_warn("The newly added mac address (%pM) already exists on: %s\n",
249 net_dev->dev_addr, hard_iface->net_dev->name);
250 pr_warn("It is strongly recommended to keep mac addresses unique to avoid problems!\n");
256 * batadv_hardif_recalc_extra_skbroom() - Recalculate skbuff extra head/tailroom
257 * @soft_iface: netdev struct of the mesh interface
259 static void batadv_hardif_recalc_extra_skbroom(struct net_device *soft_iface)
261 const struct batadv_hard_iface *hard_iface;
262 unsigned short lower_header_len = ETH_HLEN;
263 unsigned short lower_headroom = 0;
264 unsigned short lower_tailroom = 0;
265 unsigned short needed_headroom;
268 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
269 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
272 if (hard_iface->soft_iface != soft_iface)
275 lower_header_len = max_t(unsigned short, lower_header_len,
276 hard_iface->net_dev->hard_header_len);
278 lower_headroom = max_t(unsigned short, lower_headroom,
279 hard_iface->net_dev->needed_headroom);
281 lower_tailroom = max_t(unsigned short, lower_tailroom,
282 hard_iface->net_dev->needed_tailroom);
286 needed_headroom = lower_headroom + (lower_header_len - ETH_HLEN);
287 needed_headroom += batadv_max_header_len();
289 soft_iface->needed_headroom = needed_headroom;
290 soft_iface->needed_tailroom = lower_tailroom;
293 int batadv_hardif_min_mtu(struct net_device *soft_iface)
295 struct batadv_priv *bat_priv = netdev_priv(soft_iface);
296 const struct batadv_hard_iface *hard_iface;
297 int min_mtu = INT_MAX;
300 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
301 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
302 (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
305 if (hard_iface->soft_iface != soft_iface)
308 min_mtu = min_t(int, hard_iface->net_dev->mtu, min_mtu);
312 if (atomic_read(&bat_priv->fragmentation) == 0)
315 /* with fragmentation enabled the maximum size of internally generated
316 * packets such as translation table exchanges or tvlv containers, etc
317 * has to be calculated
319 min_mtu = min_t(int, min_mtu, BATADV_FRAG_MAX_FRAG_SIZE);
320 min_mtu -= sizeof(struct batadv_frag_packet);
321 min_mtu *= BATADV_FRAG_MAX_FRAGMENTS;
324 /* report to the other components the maximum amount of bytes that
325 * batman-adv can send over the wire (without considering the payload
326 * overhead). For example, this value is used by TT to compute the
327 * maximum local table table size
329 atomic_set(&bat_priv->packet_size_max, min_mtu);
331 /* the real soft-interface MTU is computed by removing the payload
332 * overhead from the maximum amount of bytes that was just computed.
334 * However batman-adv does not support MTUs bigger than ETH_DATA_LEN
336 return min_t(int, min_mtu - batadv_max_header_len(), ETH_DATA_LEN);
339 /* adjusts the MTU if a new interface with a smaller MTU appeared. */
340 void batadv_update_min_mtu(struct net_device *soft_iface)
342 soft_iface->mtu = batadv_hardif_min_mtu(soft_iface);
344 /* Check if the local translate table should be cleaned up to match a
345 * new (and smaller) MTU.
347 batadv_tt_local_resize_to_mtu(soft_iface);
351 batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface)
353 struct batadv_priv *bat_priv;
354 struct batadv_hard_iface *primary_if = NULL;
356 if (hard_iface->if_status != BATADV_IF_INACTIVE)
359 bat_priv = netdev_priv(hard_iface->soft_iface);
361 bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
362 hard_iface->if_status = BATADV_IF_TO_BE_ACTIVATED;
364 /* the first active interface becomes our primary interface or
365 * the next active interface after the old primary interface was removed
367 primary_if = batadv_primary_if_get_selected(bat_priv);
369 batadv_primary_if_select(bat_priv, hard_iface);
371 batadv_info(hard_iface->soft_iface, "Interface activated: %s\n",
372 hard_iface->net_dev->name);
374 batadv_update_min_mtu(hard_iface->soft_iface);
378 batadv_hardif_free_ref(primary_if);
382 batadv_hardif_deactivate_interface(struct batadv_hard_iface *hard_iface)
384 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
385 (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
388 hard_iface->if_status = BATADV_IF_INACTIVE;
390 batadv_info(hard_iface->soft_iface, "Interface deactivated: %s\n",
391 hard_iface->net_dev->name);
393 batadv_update_min_mtu(hard_iface->soft_iface);
397 * batadv_master_del_slave - remove hard_iface from the current master interface
398 * @slave: the interface enslaved in another master
399 * @master: the master from which slave has to be removed
401 * Invoke ndo_del_slave on master passing slave as argument. In this way slave
402 * is free'd and master can correctly change its internal state.
403 * Return 0 on success, a negative value representing the error otherwise
405 static int batadv_master_del_slave(struct batadv_hard_iface *slave,
406 struct net_device *master)
414 if (master->netdev_ops->ndo_del_slave)
415 ret = master->netdev_ops->ndo_del_slave(master, slave->net_dev);
420 int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
421 const char *iface_name)
423 struct batadv_priv *bat_priv;
424 struct net_device *soft_iface, *master;
425 __be16 ethertype = htons(ETH_P_BATMAN);
426 int max_header_len = batadv_max_header_len();
429 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
432 if (!atomic_inc_not_zero(&hard_iface->refcount))
435 soft_iface = dev_get_by_name(&init_net, iface_name);
438 soft_iface = batadv_softif_create(iface_name);
445 /* dev_get_by_name() increases the reference counter for us */
446 dev_hold(soft_iface);
449 if (!batadv_softif_is_valid(soft_iface)) {
450 pr_err("Can't create batman mesh interface %s: already exists as regular interface\n",
456 /* check if the interface is enslaved in another virtual one and
457 * in that case unlink it first
459 master = netdev_master_upper_dev_get(hard_iface->net_dev);
460 ret = batadv_master_del_slave(hard_iface, master);
464 hard_iface->soft_iface = soft_iface;
465 bat_priv = netdev_priv(hard_iface->soft_iface);
467 ret = netdev_master_upper_dev_link(hard_iface->net_dev, soft_iface);
471 ret = bat_priv->bat_algo_ops->bat_iface_enable(hard_iface);
475 hard_iface->if_num = bat_priv->num_ifaces;
476 bat_priv->num_ifaces++;
477 hard_iface->if_status = BATADV_IF_INACTIVE;
478 ret = batadv_orig_hash_add_if(hard_iface, bat_priv->num_ifaces);
480 bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
481 bat_priv->num_ifaces--;
482 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
486 hard_iface->batman_adv_ptype.type = ethertype;
487 hard_iface->batman_adv_ptype.func = batadv_batman_skb_recv;
488 hard_iface->batman_adv_ptype.dev = hard_iface->net_dev;
489 dev_add_pack(&hard_iface->batman_adv_ptype);
491 batadv_info(hard_iface->soft_iface, "Adding interface: %s\n",
492 hard_iface->net_dev->name);
494 if (atomic_read(&bat_priv->fragmentation) &&
495 hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
496 batadv_info(hard_iface->soft_iface,
497 "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",
498 hard_iface->net_dev->name, hard_iface->net_dev->mtu,
499 ETH_DATA_LEN + max_header_len);
501 if (!atomic_read(&bat_priv->fragmentation) &&
502 hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
503 batadv_info(hard_iface->soft_iface,
504 "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",
505 hard_iface->net_dev->name, hard_iface->net_dev->mtu,
506 ETH_DATA_LEN + max_header_len);
508 if (batadv_hardif_is_iface_up(hard_iface))
509 batadv_hardif_activate_interface(hard_iface);
511 batadv_err(hard_iface->soft_iface,
512 "Not using interface %s (retrying later): interface not active\n",
513 hard_iface->net_dev->name);
515 batadv_hardif_recalc_extra_skbroom(soft_iface);
517 /* begin scheduling originator messages on that interface */
518 batadv_schedule_bat_ogm(hard_iface);
524 netdev_upper_dev_unlink(hard_iface->net_dev, soft_iface);
526 hard_iface->soft_iface = NULL;
529 batadv_hardif_free_ref(hard_iface);
533 void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
534 enum batadv_hard_if_cleanup autodel)
536 struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
537 struct batadv_hard_iface *primary_if = NULL;
539 if (hard_iface->if_status == BATADV_IF_ACTIVE)
540 batadv_hardif_deactivate_interface(hard_iface);
542 if (hard_iface->if_status != BATADV_IF_INACTIVE)
545 batadv_info(hard_iface->soft_iface, "Removing interface: %s\n",
546 hard_iface->net_dev->name);
547 dev_remove_pack(&hard_iface->batman_adv_ptype);
549 bat_priv->num_ifaces--;
550 batadv_orig_hash_del_if(hard_iface, bat_priv->num_ifaces);
552 primary_if = batadv_primary_if_get_selected(bat_priv);
553 if (hard_iface == primary_if) {
554 struct batadv_hard_iface *new_if;
556 new_if = batadv_hardif_get_active(hard_iface->soft_iface);
557 batadv_primary_if_select(bat_priv, new_if);
560 batadv_hardif_free_ref(new_if);
563 bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
564 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
566 /* delete all references to this hard_iface */
567 batadv_purge_orig_ref(bat_priv);
568 batadv_purge_outstanding_packets(bat_priv, hard_iface);
569 dev_put(hard_iface->soft_iface);
571 netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);
572 batadv_hardif_recalc_extra_skbroom(hard_iface->soft_iface);
574 /* nobody uses this interface anymore */
575 if (!bat_priv->num_ifaces) {
576 batadv_gw_check_client_stop(bat_priv);
578 if (autodel == BATADV_IF_CLEANUP_AUTO)
579 batadv_softif_destroy_sysfs(hard_iface->soft_iface);
582 hard_iface->soft_iface = NULL;
583 batadv_hardif_free_ref(hard_iface);
587 batadv_hardif_free_ref(primary_if);
591 * batadv_hardif_remove_interface_finish - cleans up the remains of a hardif
592 * @work: work queue item
594 * Free the parts of the hard interface which can not be removed under
595 * rtnl lock (to prevent deadlock situations).
597 static void batadv_hardif_remove_interface_finish(struct work_struct *work)
599 struct batadv_hard_iface *hard_iface;
601 hard_iface = container_of(work, struct batadv_hard_iface,
604 batadv_debugfs_del_hardif(hard_iface);
605 batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
606 batadv_hardif_free_ref(hard_iface);
609 static struct batadv_hard_iface *
610 batadv_hardif_add_interface(struct net_device *net_dev)
612 struct batadv_hard_iface *hard_iface;
617 ret = batadv_is_valid_iface(net_dev);
623 hard_iface = kzalloc(sizeof(*hard_iface), GFP_ATOMIC);
627 ret = batadv_sysfs_add_hardif(&hard_iface->hardif_obj, net_dev);
631 hard_iface->if_num = -1;
632 hard_iface->net_dev = net_dev;
633 hard_iface->soft_iface = NULL;
634 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
636 ret = batadv_debugfs_add_hardif(hard_iface);
640 INIT_LIST_HEAD(&hard_iface->list);
641 INIT_WORK(&hard_iface->cleanup_work,
642 batadv_hardif_remove_interface_finish);
644 hard_iface->num_bcasts = BATADV_NUM_BCASTS_DEFAULT;
645 if (batadv_is_wifi_netdev(net_dev))
646 hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS;
648 /* extra reference for return */
649 atomic_set(&hard_iface->refcount, 2);
651 batadv_check_known_mac_addr(hard_iface->net_dev);
652 list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);
657 batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
666 static void batadv_hardif_remove_interface(struct batadv_hard_iface *hard_iface)
670 /* first deactivate interface */
671 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
672 batadv_hardif_disable_interface(hard_iface,
673 BATADV_IF_CLEANUP_AUTO);
675 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
678 hard_iface->if_status = BATADV_IF_TO_BE_REMOVED;
679 queue_work(batadv_event_workqueue, &hard_iface->cleanup_work);
682 void batadv_hardif_remove_interfaces(void)
684 struct batadv_hard_iface *hard_iface, *hard_iface_tmp;
687 list_for_each_entry_safe(hard_iface, hard_iface_tmp,
688 &batadv_hardif_list, list) {
689 list_del_rcu(&hard_iface->list);
690 batadv_hardif_remove_interface(hard_iface);
695 static int batadv_hard_if_event(struct notifier_block *this,
696 unsigned long event, void *ptr)
698 struct net_device *net_dev = netdev_notifier_info_to_dev(ptr);
699 struct batadv_hard_iface *hard_iface;
700 struct batadv_hard_iface *primary_if = NULL;
701 struct batadv_priv *bat_priv;
703 if (batadv_softif_is_valid(net_dev) && event == NETDEV_REGISTER) {
704 batadv_sysfs_add_meshif(net_dev);
705 bat_priv = netdev_priv(net_dev);
706 batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS);
710 hard_iface = batadv_hardif_get_by_netdev(net_dev);
711 if (!hard_iface && event == NETDEV_REGISTER)
712 hard_iface = batadv_hardif_add_interface(net_dev);
719 batadv_hardif_activate_interface(hard_iface);
721 case NETDEV_GOING_DOWN:
723 batadv_hardif_deactivate_interface(hard_iface);
725 case NETDEV_UNREGISTER:
726 list_del_rcu(&hard_iface->list);
728 batadv_hardif_remove_interface(hard_iface);
730 case NETDEV_CHANGEMTU:
731 if (hard_iface->soft_iface)
732 batadv_update_min_mtu(hard_iface->soft_iface);
734 case NETDEV_CHANGEADDR:
735 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
738 batadv_check_known_mac_addr(hard_iface->net_dev);
740 bat_priv = netdev_priv(hard_iface->soft_iface);
741 bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
743 primary_if = batadv_primary_if_get_selected(bat_priv);
747 if (hard_iface == primary_if)
748 batadv_primary_if_update_addr(bat_priv, NULL);
755 batadv_hardif_free_ref(hard_iface);
758 batadv_hardif_free_ref(primary_if);
762 struct notifier_block batadv_hard_if_notifier = {
763 .notifier_call = batadv_hard_if_event,