1 /* Copyright (C) 2007-2016 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/spinlock.h>
36 #include <linux/workqueue.h>
37 #include <net/net_namespace.h>
39 #include "bridge_loop_avoidance.h"
41 #include "distributed-arp-table.h"
42 #include "gateway_client.h"
43 #include "originator.h"
46 #include "soft-interface.h"
48 #include "translation-table.h"
50 void batadv_hardif_free_rcu(struct rcu_head *rcu)
52 struct batadv_hard_iface *hard_iface;
54 hard_iface = container_of(rcu, struct batadv_hard_iface, rcu);
55 dev_put(hard_iface->net_dev);
59 struct batadv_hard_iface *
60 batadv_hardif_get_by_netdev(const struct net_device *net_dev)
62 struct batadv_hard_iface *hard_iface;
65 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
66 if (hard_iface->net_dev == net_dev &&
67 atomic_inc_not_zero(&hard_iface->refcount))
79 * batadv_is_on_batman_iface - check if a device is a batman iface descendant
80 * @net_dev: the device to check
82 * If the user creates any virtual device on top of a batman-adv interface, it
83 * is important to prevent this new interface to be used to create a new mesh
84 * network (this behaviour would lead to a batman-over-batman configuration).
85 * This function recursively checks all the fathers of the device passed as
86 * argument looking for a batman-adv soft interface.
88 * Return: true if the device is descendant of a batman-adv mesh interface (or
89 * if it is a batman-adv interface itself), false otherwise
91 static bool batadv_is_on_batman_iface(const struct net_device *net_dev)
93 struct net_device *parent_dev;
96 /* check if this is a batman-adv mesh interface */
97 if (batadv_softif_is_valid(net_dev))
100 /* no more parents..stop recursion */
101 if (dev_get_iflink(net_dev) == 0 ||
102 dev_get_iflink(net_dev) == net_dev->ifindex)
105 /* recurse over the parent device */
106 parent_dev = __dev_get_by_index(&init_net, dev_get_iflink(net_dev));
107 /* if we got a NULL parent_dev there is something broken.. */
108 if (WARN(!parent_dev, "Cannot find parent device"))
111 ret = batadv_is_on_batman_iface(parent_dev);
116 static int batadv_is_valid_iface(const struct net_device *net_dev)
118 if (net_dev->flags & IFF_LOOPBACK)
121 if (net_dev->type != ARPHRD_ETHER)
124 if (net_dev->addr_len != ETH_ALEN)
127 /* no batman over batman */
128 if (batadv_is_on_batman_iface(net_dev))
135 * batadv_is_wifi_netdev - check if the given net_device struct is a wifi
137 * @net_device: the device to check
139 * Return: true if the net device is a 802.11 wireless device, false otherwise.
141 bool batadv_is_wifi_netdev(struct net_device *net_device)
146 #ifdef CONFIG_WIRELESS_EXT
147 /* pre-cfg80211 drivers have to implement WEXT, so it is possible to
148 * check for wireless_handlers != NULL
150 if (net_device->wireless_handlers)
154 /* cfg80211 drivers have to set ieee80211_ptr */
155 if (net_device->ieee80211_ptr)
161 static struct batadv_hard_iface *
162 batadv_hardif_get_active(const struct net_device *soft_iface)
164 struct batadv_hard_iface *hard_iface;
167 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
168 if (hard_iface->soft_iface != soft_iface)
171 if (hard_iface->if_status == BATADV_IF_ACTIVE &&
172 atomic_inc_not_zero(&hard_iface->refcount))
183 static void batadv_primary_if_update_addr(struct batadv_priv *bat_priv,
184 struct batadv_hard_iface *oldif)
186 struct batadv_hard_iface *primary_if;
188 primary_if = batadv_primary_if_get_selected(bat_priv);
192 batadv_dat_init_own_addr(bat_priv, primary_if);
193 batadv_bla_update_orig_address(bat_priv, primary_if, oldif);
196 batadv_hardif_free_ref(primary_if);
199 static void batadv_primary_if_select(struct batadv_priv *bat_priv,
200 struct batadv_hard_iface *new_hard_iface)
202 struct batadv_hard_iface *curr_hard_iface;
206 if (new_hard_iface && !atomic_inc_not_zero(&new_hard_iface->refcount))
207 new_hard_iface = NULL;
209 curr_hard_iface = rcu_dereference_protected(bat_priv->primary_if, 1);
210 rcu_assign_pointer(bat_priv->primary_if, new_hard_iface);
215 bat_priv->bat_algo_ops->bat_primary_iface_set(new_hard_iface);
216 batadv_primary_if_update_addr(bat_priv, curr_hard_iface);
220 batadv_hardif_free_ref(curr_hard_iface);
224 batadv_hardif_is_iface_up(const struct batadv_hard_iface *hard_iface)
226 if (hard_iface->net_dev->flags & IFF_UP)
232 static void batadv_check_known_mac_addr(const struct net_device *net_dev)
234 const struct batadv_hard_iface *hard_iface;
237 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
238 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
239 (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
242 if (hard_iface->net_dev == net_dev)
245 if (!batadv_compare_eth(hard_iface->net_dev->dev_addr,
249 pr_warn("The newly added mac address (%pM) already exists on: %s\n",
250 net_dev->dev_addr, hard_iface->net_dev->name);
251 pr_warn("It is strongly recommended to keep mac addresses unique to avoid problems!\n");
257 * batadv_hardif_recalc_extra_skbroom() - Recalculate skbuff extra head/tailroom
258 * @soft_iface: netdev struct of the mesh interface
260 static void batadv_hardif_recalc_extra_skbroom(struct net_device *soft_iface)
262 const struct batadv_hard_iface *hard_iface;
263 unsigned short lower_header_len = ETH_HLEN;
264 unsigned short lower_headroom = 0;
265 unsigned short lower_tailroom = 0;
266 unsigned short needed_headroom;
269 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
270 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
273 if (hard_iface->soft_iface != soft_iface)
276 lower_header_len = max_t(unsigned short, lower_header_len,
277 hard_iface->net_dev->hard_header_len);
279 lower_headroom = max_t(unsigned short, lower_headroom,
280 hard_iface->net_dev->needed_headroom);
282 lower_tailroom = max_t(unsigned short, lower_tailroom,
283 hard_iface->net_dev->needed_tailroom);
287 needed_headroom = lower_headroom + (lower_header_len - ETH_HLEN);
288 needed_headroom += batadv_max_header_len();
290 soft_iface->needed_headroom = needed_headroom;
291 soft_iface->needed_tailroom = lower_tailroom;
294 int batadv_hardif_min_mtu(struct net_device *soft_iface)
296 struct batadv_priv *bat_priv = netdev_priv(soft_iface);
297 const struct batadv_hard_iface *hard_iface;
298 int min_mtu = INT_MAX;
301 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
302 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
303 (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
306 if (hard_iface->soft_iface != soft_iface)
309 min_mtu = min_t(int, hard_iface->net_dev->mtu, min_mtu);
313 if (atomic_read(&bat_priv->fragmentation) == 0)
316 /* with fragmentation enabled the maximum size of internally generated
317 * packets such as translation table exchanges or tvlv containers, etc
318 * has to be calculated
320 min_mtu = min_t(int, min_mtu, BATADV_FRAG_MAX_FRAG_SIZE);
321 min_mtu -= sizeof(struct batadv_frag_packet);
322 min_mtu *= BATADV_FRAG_MAX_FRAGMENTS;
325 /* report to the other components the maximum amount of bytes that
326 * batman-adv can send over the wire (without considering the payload
327 * overhead). For example, this value is used by TT to compute the
328 * maximum local table table size
330 atomic_set(&bat_priv->packet_size_max, min_mtu);
332 /* the real soft-interface MTU is computed by removing the payload
333 * overhead from the maximum amount of bytes that was just computed.
335 * However batman-adv does not support MTUs bigger than ETH_DATA_LEN
337 return min_t(int, min_mtu - batadv_max_header_len(), ETH_DATA_LEN);
340 /* adjusts the MTU if a new interface with a smaller MTU appeared. */
341 void batadv_update_min_mtu(struct net_device *soft_iface)
343 soft_iface->mtu = batadv_hardif_min_mtu(soft_iface);
345 /* Check if the local translate table should be cleaned up to match a
346 * new (and smaller) MTU.
348 batadv_tt_local_resize_to_mtu(soft_iface);
352 batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface)
354 struct batadv_priv *bat_priv;
355 struct batadv_hard_iface *primary_if = NULL;
357 if (hard_iface->if_status != BATADV_IF_INACTIVE)
360 bat_priv = netdev_priv(hard_iface->soft_iface);
362 bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
363 hard_iface->if_status = BATADV_IF_TO_BE_ACTIVATED;
365 /* the first active interface becomes our primary interface or
366 * the next active interface after the old primary interface was removed
368 primary_if = batadv_primary_if_get_selected(bat_priv);
370 batadv_primary_if_select(bat_priv, hard_iface);
372 batadv_info(hard_iface->soft_iface, "Interface activated: %s\n",
373 hard_iface->net_dev->name);
375 batadv_update_min_mtu(hard_iface->soft_iface);
379 batadv_hardif_free_ref(primary_if);
383 batadv_hardif_deactivate_interface(struct batadv_hard_iface *hard_iface)
385 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
386 (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
389 hard_iface->if_status = BATADV_IF_INACTIVE;
391 batadv_info(hard_iface->soft_iface, "Interface deactivated: %s\n",
392 hard_iface->net_dev->name);
394 batadv_update_min_mtu(hard_iface->soft_iface);
398 * batadv_master_del_slave - remove hard_iface from the current master interface
399 * @slave: the interface enslaved in another master
400 * @master: the master from which slave has to be removed
402 * Invoke ndo_del_slave on master passing slave as argument. In this way slave
403 * is free'd and master can correctly change its internal state.
405 * Return: 0 on success, a negative value representing the error otherwise
407 static int batadv_master_del_slave(struct batadv_hard_iface *slave,
408 struct net_device *master)
416 if (master->netdev_ops->ndo_del_slave)
417 ret = master->netdev_ops->ndo_del_slave(master, slave->net_dev);
422 int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
423 const char *iface_name)
425 struct batadv_priv *bat_priv;
426 struct net_device *soft_iface, *master;
427 __be16 ethertype = htons(ETH_P_BATMAN);
428 int max_header_len = batadv_max_header_len();
431 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
434 if (!atomic_inc_not_zero(&hard_iface->refcount))
437 soft_iface = dev_get_by_name(&init_net, iface_name);
440 soft_iface = batadv_softif_create(iface_name);
447 /* dev_get_by_name() increases the reference counter for us */
448 dev_hold(soft_iface);
451 if (!batadv_softif_is_valid(soft_iface)) {
452 pr_err("Can't create batman mesh interface %s: already exists as regular interface\n",
458 /* check if the interface is enslaved in another virtual one and
459 * in that case unlink it first
461 master = netdev_master_upper_dev_get(hard_iface->net_dev);
462 ret = batadv_master_del_slave(hard_iface, master);
466 hard_iface->soft_iface = soft_iface;
467 bat_priv = netdev_priv(hard_iface->soft_iface);
469 ret = netdev_master_upper_dev_link(hard_iface->net_dev,
470 soft_iface, NULL, NULL);
474 ret = bat_priv->bat_algo_ops->bat_iface_enable(hard_iface);
478 hard_iface->if_num = bat_priv->num_ifaces;
479 bat_priv->num_ifaces++;
480 hard_iface->if_status = BATADV_IF_INACTIVE;
481 ret = batadv_orig_hash_add_if(hard_iface, bat_priv->num_ifaces);
483 bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
484 bat_priv->num_ifaces--;
485 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
489 hard_iface->batman_adv_ptype.type = ethertype;
490 hard_iface->batman_adv_ptype.func = batadv_batman_skb_recv;
491 hard_iface->batman_adv_ptype.dev = hard_iface->net_dev;
492 dev_add_pack(&hard_iface->batman_adv_ptype);
494 batadv_info(hard_iface->soft_iface, "Adding interface: %s\n",
495 hard_iface->net_dev->name);
497 if (atomic_read(&bat_priv->fragmentation) &&
498 hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
499 batadv_info(hard_iface->soft_iface,
500 "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",
501 hard_iface->net_dev->name, hard_iface->net_dev->mtu,
502 ETH_DATA_LEN + max_header_len);
504 if (!atomic_read(&bat_priv->fragmentation) &&
505 hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
506 batadv_info(hard_iface->soft_iface,
507 "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",
508 hard_iface->net_dev->name, hard_iface->net_dev->mtu,
509 ETH_DATA_LEN + max_header_len);
511 if (batadv_hardif_is_iface_up(hard_iface))
512 batadv_hardif_activate_interface(hard_iface);
514 batadv_err(hard_iface->soft_iface,
515 "Not using interface %s (retrying later): interface not active\n",
516 hard_iface->net_dev->name);
518 batadv_hardif_recalc_extra_skbroom(soft_iface);
520 /* begin scheduling originator messages on that interface */
521 batadv_schedule_bat_ogm(hard_iface);
527 netdev_upper_dev_unlink(hard_iface->net_dev, soft_iface);
529 hard_iface->soft_iface = NULL;
532 batadv_hardif_free_ref(hard_iface);
536 void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
537 enum batadv_hard_if_cleanup autodel)
539 struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
540 struct batadv_hard_iface *primary_if = NULL;
542 if (hard_iface->if_status == BATADV_IF_ACTIVE)
543 batadv_hardif_deactivate_interface(hard_iface);
545 if (hard_iface->if_status != BATADV_IF_INACTIVE)
548 batadv_info(hard_iface->soft_iface, "Removing interface: %s\n",
549 hard_iface->net_dev->name);
550 dev_remove_pack(&hard_iface->batman_adv_ptype);
552 bat_priv->num_ifaces--;
553 batadv_orig_hash_del_if(hard_iface, bat_priv->num_ifaces);
555 primary_if = batadv_primary_if_get_selected(bat_priv);
556 if (hard_iface == primary_if) {
557 struct batadv_hard_iface *new_if;
559 new_if = batadv_hardif_get_active(hard_iface->soft_iface);
560 batadv_primary_if_select(bat_priv, new_if);
563 batadv_hardif_free_ref(new_if);
566 bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
567 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
569 /* delete all references to this hard_iface */
570 batadv_purge_orig_ref(bat_priv);
571 batadv_purge_outstanding_packets(bat_priv, hard_iface);
572 dev_put(hard_iface->soft_iface);
574 netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);
575 batadv_hardif_recalc_extra_skbroom(hard_iface->soft_iface);
577 /* nobody uses this interface anymore */
578 if (!bat_priv->num_ifaces) {
579 batadv_gw_check_client_stop(bat_priv);
581 if (autodel == BATADV_IF_CLEANUP_AUTO)
582 batadv_softif_destroy_sysfs(hard_iface->soft_iface);
585 hard_iface->soft_iface = NULL;
586 batadv_hardif_free_ref(hard_iface);
590 batadv_hardif_free_ref(primary_if);
594 * batadv_hardif_remove_interface_finish - cleans up the remains of a hardif
595 * @work: work queue item
597 * Free the parts of the hard interface which can not be removed under
598 * rtnl lock (to prevent deadlock situations).
600 static void batadv_hardif_remove_interface_finish(struct work_struct *work)
602 struct batadv_hard_iface *hard_iface;
604 hard_iface = container_of(work, struct batadv_hard_iface,
607 batadv_debugfs_del_hardif(hard_iface);
608 batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
609 batadv_hardif_free_ref(hard_iface);
612 static struct batadv_hard_iface *
613 batadv_hardif_add_interface(struct net_device *net_dev)
615 struct batadv_hard_iface *hard_iface;
620 ret = batadv_is_valid_iface(net_dev);
626 hard_iface = kzalloc(sizeof(*hard_iface), GFP_ATOMIC);
630 ret = batadv_sysfs_add_hardif(&hard_iface->hardif_obj, net_dev);
634 hard_iface->if_num = -1;
635 hard_iface->net_dev = net_dev;
636 hard_iface->soft_iface = NULL;
637 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
639 ret = batadv_debugfs_add_hardif(hard_iface);
643 INIT_LIST_HEAD(&hard_iface->list);
644 INIT_HLIST_HEAD(&hard_iface->neigh_list);
645 INIT_WORK(&hard_iface->cleanup_work,
646 batadv_hardif_remove_interface_finish);
648 spin_lock_init(&hard_iface->neigh_list_lock);
650 hard_iface->num_bcasts = BATADV_NUM_BCASTS_DEFAULT;
651 if (batadv_is_wifi_netdev(net_dev))
652 hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS;
654 /* extra reference for return */
655 atomic_set(&hard_iface->refcount, 2);
657 batadv_check_known_mac_addr(hard_iface->net_dev);
658 list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);
663 batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
672 static void batadv_hardif_remove_interface(struct batadv_hard_iface *hard_iface)
676 /* first deactivate interface */
677 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
678 batadv_hardif_disable_interface(hard_iface,
679 BATADV_IF_CLEANUP_AUTO);
681 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
684 hard_iface->if_status = BATADV_IF_TO_BE_REMOVED;
685 queue_work(batadv_event_workqueue, &hard_iface->cleanup_work);
688 void batadv_hardif_remove_interfaces(void)
690 struct batadv_hard_iface *hard_iface, *hard_iface_tmp;
693 list_for_each_entry_safe(hard_iface, hard_iface_tmp,
694 &batadv_hardif_list, list) {
695 list_del_rcu(&hard_iface->list);
696 batadv_hardif_remove_interface(hard_iface);
701 static int batadv_hard_if_event(struct notifier_block *this,
702 unsigned long event, void *ptr)
704 struct net_device *net_dev = netdev_notifier_info_to_dev(ptr);
705 struct batadv_hard_iface *hard_iface;
706 struct batadv_hard_iface *primary_if = NULL;
707 struct batadv_priv *bat_priv;
709 if (batadv_softif_is_valid(net_dev) && event == NETDEV_REGISTER) {
710 batadv_sysfs_add_meshif(net_dev);
711 bat_priv = netdev_priv(net_dev);
712 batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS);
716 hard_iface = batadv_hardif_get_by_netdev(net_dev);
717 if (!hard_iface && (event == NETDEV_REGISTER ||
718 event == NETDEV_POST_TYPE_CHANGE))
719 hard_iface = batadv_hardif_add_interface(net_dev);
726 batadv_hardif_activate_interface(hard_iface);
728 case NETDEV_GOING_DOWN:
730 batadv_hardif_deactivate_interface(hard_iface);
732 case NETDEV_UNREGISTER:
733 case NETDEV_PRE_TYPE_CHANGE:
734 list_del_rcu(&hard_iface->list);
736 batadv_hardif_remove_interface(hard_iface);
738 case NETDEV_CHANGEMTU:
739 if (hard_iface->soft_iface)
740 batadv_update_min_mtu(hard_iface->soft_iface);
742 case NETDEV_CHANGEADDR:
743 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
746 batadv_check_known_mac_addr(hard_iface->net_dev);
748 bat_priv = netdev_priv(hard_iface->soft_iface);
749 bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
751 primary_if = batadv_primary_if_get_selected(bat_priv);
755 if (hard_iface == primary_if)
756 batadv_primary_if_update_addr(bat_priv, NULL);
763 batadv_hardif_free_ref(hard_iface);
766 batadv_hardif_free_ref(primary_if);
770 struct notifier_block batadv_hard_if_notifier = {
771 .notifier_call = batadv_hard_if_event,