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/atomic.h>
22 #include <linux/bug.h>
23 #include <linux/byteorder/generic.h>
24 #include <linux/errno.h>
26 #include <linux/if_arp.h>
27 #include <linux/if_ether.h>
29 #include <linux/kernel.h>
30 #include <linux/kref.h>
31 #include <linux/list.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 <linux/workqueue.h>
39 #include <net/net_namespace.h>
41 #include "bridge_loop_avoidance.h"
43 #include "distributed-arp-table.h"
44 #include "gateway_client.h"
45 #include "originator.h"
48 #include "soft-interface.h"
50 #include "translation-table.h"
53 * batadv_hardif_release - release hard interface from lists and queue for
54 * free after rcu grace period
55 * @ref: kref pointer of the hard interface
57 void batadv_hardif_release(struct kref *ref)
59 struct batadv_hard_iface *hard_iface;
61 hard_iface = container_of(ref, struct batadv_hard_iface, refcount);
62 dev_put(hard_iface->net_dev);
64 kfree_rcu(hard_iface, rcu);
67 struct batadv_hard_iface *
68 batadv_hardif_get_by_netdev(const struct net_device *net_dev)
70 struct batadv_hard_iface *hard_iface;
73 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
74 if (hard_iface->net_dev == net_dev &&
75 kref_get_unless_zero(&hard_iface->refcount))
87 * batadv_mutual_parents - check if two devices are each others parent
88 * @dev1: 1st net_device
89 * @dev2: 2nd net_device
91 * veth devices come in pairs and each is the parent of the other!
93 * Return: true if the devices are each others parent, otherwise false
95 static bool batadv_mutual_parents(const struct net_device *dev1,
96 const struct net_device *dev2)
98 int dev1_parent_iflink = dev_get_iflink(dev1);
99 int dev2_parent_iflink = dev_get_iflink(dev2);
101 if (!dev1_parent_iflink || !dev2_parent_iflink)
104 return (dev1_parent_iflink == dev2->ifindex) &&
105 (dev2_parent_iflink == dev1->ifindex);
109 * batadv_is_on_batman_iface - check if a device is a batman iface descendant
110 * @net_dev: the device to check
112 * If the user creates any virtual device on top of a batman-adv interface, it
113 * is important to prevent this new interface to be used to create a new mesh
114 * network (this behaviour would lead to a batman-over-batman configuration).
115 * This function recursively checks all the fathers of the device passed as
116 * argument looking for a batman-adv soft interface.
118 * Return: true if the device is descendant of a batman-adv mesh interface (or
119 * if it is a batman-adv interface itself), false otherwise
121 static bool batadv_is_on_batman_iface(const struct net_device *net_dev)
123 struct net_device *parent_dev;
126 /* check if this is a batman-adv mesh interface */
127 if (batadv_softif_is_valid(net_dev))
130 /* no more parents..stop recursion */
131 if (dev_get_iflink(net_dev) == 0 ||
132 dev_get_iflink(net_dev) == net_dev->ifindex)
135 /* recurse over the parent device */
136 parent_dev = __dev_get_by_index(&init_net, dev_get_iflink(net_dev));
137 /* if we got a NULL parent_dev there is something broken.. */
138 if (WARN(!parent_dev, "Cannot find parent device"))
141 if (batadv_mutual_parents(net_dev, parent_dev))
144 ret = batadv_is_on_batman_iface(parent_dev);
149 static int batadv_is_valid_iface(const struct net_device *net_dev)
151 if (net_dev->flags & IFF_LOOPBACK)
154 if (net_dev->type != ARPHRD_ETHER)
157 if (net_dev->addr_len != ETH_ALEN)
160 /* no batman over batman */
161 if (batadv_is_on_batman_iface(net_dev))
168 * batadv_is_wifi_netdev - check if the given net_device struct is a wifi
170 * @net_device: the device to check
172 * Return: true if the net device is a 802.11 wireless device, false otherwise.
174 bool batadv_is_wifi_netdev(struct net_device *net_device)
179 #ifdef CONFIG_WIRELESS_EXT
180 /* pre-cfg80211 drivers have to implement WEXT, so it is possible to
181 * check for wireless_handlers != NULL
183 if (net_device->wireless_handlers)
187 /* cfg80211 drivers have to set ieee80211_ptr */
188 if (net_device->ieee80211_ptr)
194 static struct batadv_hard_iface *
195 batadv_hardif_get_active(const struct net_device *soft_iface)
197 struct batadv_hard_iface *hard_iface;
200 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
201 if (hard_iface->soft_iface != soft_iface)
204 if (hard_iface->if_status == BATADV_IF_ACTIVE &&
205 kref_get_unless_zero(&hard_iface->refcount))
216 static void batadv_primary_if_update_addr(struct batadv_priv *bat_priv,
217 struct batadv_hard_iface *oldif)
219 struct batadv_hard_iface *primary_if;
221 primary_if = batadv_primary_if_get_selected(bat_priv);
225 batadv_dat_init_own_addr(bat_priv, primary_if);
226 batadv_bla_update_orig_address(bat_priv, primary_if, oldif);
229 batadv_hardif_put(primary_if);
232 static void batadv_primary_if_select(struct batadv_priv *bat_priv,
233 struct batadv_hard_iface *new_hard_iface)
235 struct batadv_hard_iface *curr_hard_iface;
239 if (new_hard_iface && !kref_get_unless_zero(&new_hard_iface->refcount))
240 new_hard_iface = NULL;
242 curr_hard_iface = rcu_dereference_protected(bat_priv->primary_if, 1);
243 rcu_assign_pointer(bat_priv->primary_if, new_hard_iface);
248 bat_priv->bat_algo_ops->bat_primary_iface_set(new_hard_iface);
249 batadv_primary_if_update_addr(bat_priv, curr_hard_iface);
253 batadv_hardif_put(curr_hard_iface);
257 batadv_hardif_is_iface_up(const struct batadv_hard_iface *hard_iface)
259 if (hard_iface->net_dev->flags & IFF_UP)
265 static void batadv_check_known_mac_addr(const struct net_device *net_dev)
267 const struct batadv_hard_iface *hard_iface;
270 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
271 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
272 (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
275 if (hard_iface->net_dev == net_dev)
278 if (!batadv_compare_eth(hard_iface->net_dev->dev_addr,
282 pr_warn("The newly added mac address (%pM) already exists on: %s\n",
283 net_dev->dev_addr, hard_iface->net_dev->name);
284 pr_warn("It is strongly recommended to keep mac addresses unique to avoid problems!\n");
290 * batadv_hardif_recalc_extra_skbroom() - Recalculate skbuff extra head/tailroom
291 * @soft_iface: netdev struct of the mesh interface
293 static void batadv_hardif_recalc_extra_skbroom(struct net_device *soft_iface)
295 const struct batadv_hard_iface *hard_iface;
296 unsigned short lower_header_len = ETH_HLEN;
297 unsigned short lower_headroom = 0;
298 unsigned short lower_tailroom = 0;
299 unsigned short needed_headroom;
302 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
303 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
306 if (hard_iface->soft_iface != soft_iface)
309 lower_header_len = max_t(unsigned short, lower_header_len,
310 hard_iface->net_dev->hard_header_len);
312 lower_headroom = max_t(unsigned short, lower_headroom,
313 hard_iface->net_dev->needed_headroom);
315 lower_tailroom = max_t(unsigned short, lower_tailroom,
316 hard_iface->net_dev->needed_tailroom);
320 needed_headroom = lower_headroom + (lower_header_len - ETH_HLEN);
321 needed_headroom += batadv_max_header_len();
323 soft_iface->needed_headroom = needed_headroom;
324 soft_iface->needed_tailroom = lower_tailroom;
327 int batadv_hardif_min_mtu(struct net_device *soft_iface)
329 struct batadv_priv *bat_priv = netdev_priv(soft_iface);
330 const struct batadv_hard_iface *hard_iface;
331 int min_mtu = INT_MAX;
334 list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
335 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
336 (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
339 if (hard_iface->soft_iface != soft_iface)
342 min_mtu = min_t(int, hard_iface->net_dev->mtu, min_mtu);
346 if (atomic_read(&bat_priv->fragmentation) == 0)
349 /* with fragmentation enabled the maximum size of internally generated
350 * packets such as translation table exchanges or tvlv containers, etc
351 * has to be calculated
353 min_mtu = min_t(int, min_mtu, BATADV_FRAG_MAX_FRAG_SIZE);
354 min_mtu -= sizeof(struct batadv_frag_packet);
355 min_mtu *= BATADV_FRAG_MAX_FRAGMENTS;
358 /* report to the other components the maximum amount of bytes that
359 * batman-adv can send over the wire (without considering the payload
360 * overhead). For example, this value is used by TT to compute the
361 * maximum local table table size
363 atomic_set(&bat_priv->packet_size_max, min_mtu);
365 /* the real soft-interface MTU is computed by removing the payload
366 * overhead from the maximum amount of bytes that was just computed.
368 * However batman-adv does not support MTUs bigger than ETH_DATA_LEN
370 return min_t(int, min_mtu - batadv_max_header_len(), ETH_DATA_LEN);
373 /* adjusts the MTU if a new interface with a smaller MTU appeared. */
374 void batadv_update_min_mtu(struct net_device *soft_iface)
376 soft_iface->mtu = batadv_hardif_min_mtu(soft_iface);
378 /* Check if the local translate table should be cleaned up to match a
379 * new (and smaller) MTU.
381 batadv_tt_local_resize_to_mtu(soft_iface);
385 batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface)
387 struct batadv_priv *bat_priv;
388 struct batadv_hard_iface *primary_if = NULL;
390 if (hard_iface->if_status != BATADV_IF_INACTIVE)
393 bat_priv = netdev_priv(hard_iface->soft_iface);
395 bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
396 hard_iface->if_status = BATADV_IF_TO_BE_ACTIVATED;
398 /* the first active interface becomes our primary interface or
399 * the next active interface after the old primary interface was removed
401 primary_if = batadv_primary_if_get_selected(bat_priv);
403 batadv_primary_if_select(bat_priv, hard_iface);
405 batadv_info(hard_iface->soft_iface, "Interface activated: %s\n",
406 hard_iface->net_dev->name);
408 batadv_update_min_mtu(hard_iface->soft_iface);
412 batadv_hardif_put(primary_if);
416 batadv_hardif_deactivate_interface(struct batadv_hard_iface *hard_iface)
418 if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
419 (hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
422 hard_iface->if_status = BATADV_IF_INACTIVE;
424 batadv_info(hard_iface->soft_iface, "Interface deactivated: %s\n",
425 hard_iface->net_dev->name);
427 batadv_update_min_mtu(hard_iface->soft_iface);
431 * batadv_master_del_slave - remove hard_iface from the current master interface
432 * @slave: the interface enslaved in another master
433 * @master: the master from which slave has to be removed
435 * Invoke ndo_del_slave on master passing slave as argument. In this way slave
436 * is free'd and master can correctly change its internal state.
438 * Return: 0 on success, a negative value representing the error otherwise
440 static int batadv_master_del_slave(struct batadv_hard_iface *slave,
441 struct net_device *master)
449 if (master->netdev_ops->ndo_del_slave)
450 ret = master->netdev_ops->ndo_del_slave(master, slave->net_dev);
455 int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
456 const char *iface_name)
458 struct batadv_priv *bat_priv;
459 struct net_device *soft_iface, *master;
460 __be16 ethertype = htons(ETH_P_BATMAN);
461 int max_header_len = batadv_max_header_len();
464 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
467 if (!kref_get_unless_zero(&hard_iface->refcount))
470 soft_iface = dev_get_by_name(&init_net, iface_name);
473 soft_iface = batadv_softif_create(iface_name);
480 /* dev_get_by_name() increases the reference counter for us */
481 dev_hold(soft_iface);
484 if (!batadv_softif_is_valid(soft_iface)) {
485 pr_err("Can't create batman mesh interface %s: already exists as regular interface\n",
491 /* check if the interface is enslaved in another virtual one and
492 * in that case unlink it first
494 master = netdev_master_upper_dev_get(hard_iface->net_dev);
495 ret = batadv_master_del_slave(hard_iface, master);
499 hard_iface->soft_iface = soft_iface;
500 bat_priv = netdev_priv(hard_iface->soft_iface);
502 ret = netdev_master_upper_dev_link(hard_iface->net_dev,
503 soft_iface, NULL, NULL);
507 ret = bat_priv->bat_algo_ops->bat_iface_enable(hard_iface);
511 hard_iface->if_num = bat_priv->num_ifaces;
512 bat_priv->num_ifaces++;
513 hard_iface->if_status = BATADV_IF_INACTIVE;
514 ret = batadv_orig_hash_add_if(hard_iface, bat_priv->num_ifaces);
516 bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
517 bat_priv->num_ifaces--;
518 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
522 hard_iface->batman_adv_ptype.type = ethertype;
523 hard_iface->batman_adv_ptype.func = batadv_batman_skb_recv;
524 hard_iface->batman_adv_ptype.dev = hard_iface->net_dev;
525 dev_add_pack(&hard_iface->batman_adv_ptype);
527 batadv_info(hard_iface->soft_iface, "Adding interface: %s\n",
528 hard_iface->net_dev->name);
530 if (atomic_read(&bat_priv->fragmentation) &&
531 hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
532 batadv_info(hard_iface->soft_iface,
533 "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",
534 hard_iface->net_dev->name, hard_iface->net_dev->mtu,
535 ETH_DATA_LEN + max_header_len);
537 if (!atomic_read(&bat_priv->fragmentation) &&
538 hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len)
539 batadv_info(hard_iface->soft_iface,
540 "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",
541 hard_iface->net_dev->name, hard_iface->net_dev->mtu,
542 ETH_DATA_LEN + max_header_len);
544 if (batadv_hardif_is_iface_up(hard_iface))
545 batadv_hardif_activate_interface(hard_iface);
547 batadv_err(hard_iface->soft_iface,
548 "Not using interface %s (retrying later): interface not active\n",
549 hard_iface->net_dev->name);
551 batadv_hardif_recalc_extra_skbroom(soft_iface);
553 /* begin scheduling originator messages on that interface */
554 batadv_schedule_bat_ogm(hard_iface);
560 netdev_upper_dev_unlink(hard_iface->net_dev, soft_iface);
562 hard_iface->soft_iface = NULL;
565 batadv_hardif_put(hard_iface);
569 void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
570 enum batadv_hard_if_cleanup autodel)
572 struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
573 struct batadv_hard_iface *primary_if = NULL;
575 if (hard_iface->if_status == BATADV_IF_ACTIVE)
576 batadv_hardif_deactivate_interface(hard_iface);
578 if (hard_iface->if_status != BATADV_IF_INACTIVE)
581 batadv_info(hard_iface->soft_iface, "Removing interface: %s\n",
582 hard_iface->net_dev->name);
583 dev_remove_pack(&hard_iface->batman_adv_ptype);
585 bat_priv->num_ifaces--;
586 batadv_orig_hash_del_if(hard_iface, bat_priv->num_ifaces);
588 primary_if = batadv_primary_if_get_selected(bat_priv);
589 if (hard_iface == primary_if) {
590 struct batadv_hard_iface *new_if;
592 new_if = batadv_hardif_get_active(hard_iface->soft_iface);
593 batadv_primary_if_select(bat_priv, new_if);
596 batadv_hardif_put(new_if);
599 bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
600 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
602 /* delete all references to this hard_iface */
603 batadv_purge_orig_ref(bat_priv);
604 batadv_purge_outstanding_packets(bat_priv, hard_iface);
605 dev_put(hard_iface->soft_iface);
607 netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);
608 batadv_hardif_recalc_extra_skbroom(hard_iface->soft_iface);
610 /* nobody uses this interface anymore */
611 if (!bat_priv->num_ifaces) {
612 batadv_gw_check_client_stop(bat_priv);
614 if (autodel == BATADV_IF_CLEANUP_AUTO)
615 batadv_softif_destroy_sysfs(hard_iface->soft_iface);
618 hard_iface->soft_iface = NULL;
619 batadv_hardif_put(hard_iface);
623 batadv_hardif_put(primary_if);
627 * batadv_hardif_remove_interface_finish - cleans up the remains of a hardif
628 * @work: work queue item
630 * Free the parts of the hard interface which can not be removed under
631 * rtnl lock (to prevent deadlock situations).
633 static void batadv_hardif_remove_interface_finish(struct work_struct *work)
635 struct batadv_hard_iface *hard_iface;
637 hard_iface = container_of(work, struct batadv_hard_iface,
640 batadv_debugfs_del_hardif(hard_iface);
641 batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
642 batadv_hardif_put(hard_iface);
645 static struct batadv_hard_iface *
646 batadv_hardif_add_interface(struct net_device *net_dev)
648 struct batadv_hard_iface *hard_iface;
653 ret = batadv_is_valid_iface(net_dev);
659 hard_iface = kzalloc(sizeof(*hard_iface), GFP_ATOMIC);
663 ret = batadv_sysfs_add_hardif(&hard_iface->hardif_obj, net_dev);
667 hard_iface->if_num = -1;
668 hard_iface->net_dev = net_dev;
669 hard_iface->soft_iface = NULL;
670 hard_iface->if_status = BATADV_IF_NOT_IN_USE;
672 ret = batadv_debugfs_add_hardif(hard_iface);
676 INIT_LIST_HEAD(&hard_iface->list);
677 INIT_HLIST_HEAD(&hard_iface->neigh_list);
678 INIT_WORK(&hard_iface->cleanup_work,
679 batadv_hardif_remove_interface_finish);
681 spin_lock_init(&hard_iface->neigh_list_lock);
683 hard_iface->num_bcasts = BATADV_NUM_BCASTS_DEFAULT;
684 if (batadv_is_wifi_netdev(net_dev))
685 hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS;
687 /* extra reference for return */
688 kref_init(&hard_iface->refcount);
689 kref_get(&hard_iface->refcount);
691 batadv_check_known_mac_addr(hard_iface->net_dev);
692 list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);
697 batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
706 static void batadv_hardif_remove_interface(struct batadv_hard_iface *hard_iface)
710 /* first deactivate interface */
711 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
712 batadv_hardif_disable_interface(hard_iface,
713 BATADV_IF_CLEANUP_AUTO);
715 if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
718 hard_iface->if_status = BATADV_IF_TO_BE_REMOVED;
719 queue_work(batadv_event_workqueue, &hard_iface->cleanup_work);
722 void batadv_hardif_remove_interfaces(void)
724 struct batadv_hard_iface *hard_iface, *hard_iface_tmp;
727 list_for_each_entry_safe(hard_iface, hard_iface_tmp,
728 &batadv_hardif_list, list) {
729 list_del_rcu(&hard_iface->list);
730 batadv_hardif_remove_interface(hard_iface);
735 static int batadv_hard_if_event(struct notifier_block *this,
736 unsigned long event, void *ptr)
738 struct net_device *net_dev = netdev_notifier_info_to_dev(ptr);
739 struct batadv_hard_iface *hard_iface;
740 struct batadv_hard_iface *primary_if = NULL;
741 struct batadv_priv *bat_priv;
743 if (batadv_softif_is_valid(net_dev) && event == NETDEV_REGISTER) {
744 batadv_sysfs_add_meshif(net_dev);
745 bat_priv = netdev_priv(net_dev);
746 batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS);
750 hard_iface = batadv_hardif_get_by_netdev(net_dev);
751 if (!hard_iface && (event == NETDEV_REGISTER ||
752 event == NETDEV_POST_TYPE_CHANGE))
753 hard_iface = batadv_hardif_add_interface(net_dev);
760 batadv_hardif_activate_interface(hard_iface);
762 case NETDEV_GOING_DOWN:
764 batadv_hardif_deactivate_interface(hard_iface);
766 case NETDEV_UNREGISTER:
767 case NETDEV_PRE_TYPE_CHANGE:
768 list_del_rcu(&hard_iface->list);
770 batadv_hardif_remove_interface(hard_iface);
772 case NETDEV_CHANGEMTU:
773 if (hard_iface->soft_iface)
774 batadv_update_min_mtu(hard_iface->soft_iface);
776 case NETDEV_CHANGEADDR:
777 if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
780 batadv_check_known_mac_addr(hard_iface->net_dev);
782 bat_priv = netdev_priv(hard_iface->soft_iface);
783 bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
785 primary_if = batadv_primary_if_get_selected(bat_priv);
789 if (hard_iface == primary_if)
790 batadv_primary_if_update_addr(bat_priv, NULL);
797 batadv_hardif_put(hard_iface);
800 batadv_hardif_put(primary_if);
804 struct notifier_block batadv_hard_if_notifier = {
805 .notifier_call = batadv_hard_if_event,