/* Copyright (C) 2007-2013 B.A.T.M.A.N. contributors:
*
* Marek Lindner, Simon Wunderlich
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA
*/
#include "main.h"
#include "distributed-arp-table.h"
#include "hard-interface.h"
#include "soft-interface.h"
#include "send.h"
#include "translation-table.h"
#include "routing.h"
#include "sysfs.h"
#include "originator.h"
#include "hash.h"
#include "bridge_loop_avoidance.h"
#include <linux/if_arp.h>
#include <linux/if_ether.h>
void batadv_hardif_free_rcu(struct rcu_head *rcu)
{
struct batadv_hard_iface *hard_iface;
hard_iface = container_of(rcu, struct batadv_hard_iface, rcu);
dev_put(hard_iface->net_dev);
kfree(hard_iface);
}
struct batadv_hard_iface *
batadv_hardif_get_by_netdev(const struct net_device *net_dev)
{
struct batadv_hard_iface *hard_iface;
rcu_read_lock();
list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
if (hard_iface->net_dev == net_dev &&
atomic_inc_not_zero(&hard_iface->refcount))
goto out;
}
hard_iface = NULL;
out:
rcu_read_unlock();
return hard_iface;
}
/**
* batadv_is_on_batman_iface - check if a device is a batman iface descendant
* @net_dev: the device to check
*
* If the user creates any virtual device on top of a batman-adv interface, it
* is important to prevent this new interface to be used to create a new mesh
* network (this behaviour would lead to a batman-over-batman configuration).
* This function recursively checks all the fathers of the device passed as
* argument looking for a batman-adv soft interface.
*
* Returns true if the device is descendant of a batman-adv mesh interface (or
* if it is a batman-adv interface itself), false otherwise
*/
static bool batadv_is_on_batman_iface(const struct net_device *net_dev)
{
struct net_device *parent_dev;
bool ret;
/* check if this is a batman-adv mesh interface */
if (batadv_softif_is_valid(net_dev))
return true;
/* no more parents..stop recursion */
if (net_dev->iflink == net_dev->ifindex)
return false;
/* recurse over the parent device */
parent_dev = dev_get_by_index(&init_net, net_dev->iflink);
/* if we got a NULL parent_dev there is something broken.. */
if (WARN(!parent_dev, "Cannot find parent device"))
return false;
ret = batadv_is_on_batman_iface(parent_dev);
if (parent_dev)
dev_put(parent_dev);
return ret;
}
static int batadv_is_valid_iface(const struct net_device *net_dev)
{
if (net_dev->flags & IFF_LOOPBACK)
return 0;
if (net_dev->type != ARPHRD_ETHER)
return 0;
if (net_dev->addr_len != ETH_ALEN)
return 0;
/* no batman over batman */
if (batadv_is_on_batman_iface(net_dev))
return 0;
return 1;
}
static struct batadv_hard_iface *
batadv_hardif_get_active(const struct net_device *soft_iface)
{
struct batadv_hard_iface *hard_iface;
rcu_read_lock();
list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
if (hard_iface->soft_iface != soft_iface)
continue;
if (hard_iface->if_status == BATADV_IF_ACTIVE &&
atomic_inc_not_zero(&hard_iface->refcount))
goto out;
}
hard_iface = NULL;
out:
rcu_read_unlock();
return hard_iface;
}
static void batadv_primary_if_update_addr(struct batadv_priv *bat_priv,
struct batadv_hard_iface *oldif)
{
struct batadv_vis_packet *vis_packet;
struct batadv_hard_iface *primary_if;
struct sk_buff *skb;
primary_if = batadv_primary_if_get_selected(bat_priv);
if (!primary_if)
goto out;
batadv_dat_init_own_addr(bat_priv, primary_if);
skb = bat_priv->vis.my_info->skb_packet;
vis_packet = (struct batadv_vis_packet *)skb->data;
memcpy(vis_packet->vis_orig, primary_if->net_dev->dev_addr, ETH_ALEN);
memcpy(vis_packet->sender_orig,
primary_if->net_dev->dev_addr, ETH_ALEN);
batadv_bla_update_orig_address(bat_priv, primary_if, oldif);
out:
if (primary_if)
batadv_hardif_free_ref(primary_if);
}
static void batadv_primary_if_select(struct batadv_priv *bat_priv,
struct batadv_hard_iface *new_hard_iface)
{
struct batadv_hard_iface *curr_hard_iface;
ASSERT_RTNL();
if (new_hard_iface && !atomic_inc_not_zero(&new_hard_iface->refcount))
new_hard_iface = NULL;
curr_hard_iface = rcu_dereference_protected(bat_priv->primary_if, 1);
rcu_assign_pointer(bat_priv->primary_if, new_hard_iface);
if (!new_hard_iface)
goto out;
bat_priv->bat_algo_ops->bat_primary_iface_set(new_hard_iface);
batadv_primary_if_update_addr(bat_priv, curr_hard_iface);
out:
if (curr_hard_iface)
batadv_hardif_free_ref(curr_hard_iface);
}
static bool
batadv_hardif_is_iface_up(const struct batadv_hard_iface *hard_iface)
{
if (hard_iface->net_dev->flags & IFF_UP)
return true;
return false;
}
static void batadv_check_known_mac_addr(const struct net_device *net_dev)
{
const struct batadv_hard_iface *hard_iface;
rcu_read_lock();
list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
(hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
continue;
if (hard_iface->net_dev == net_dev)
continue;
if (!batadv_compare_eth(hard_iface->net_dev->dev_addr,
net_dev->dev_addr))
continue;
pr_warn("The newly added mac address (%pM) already exists on: %s\n",
net_dev->dev_addr, hard_iface->net_dev->name);
pr_warn("It is strongly recommended to keep mac addresses unique to avoid problems!\n");
}
rcu_read_unlock();
}
int batadv_hardif_min_mtu(struct net_device *soft_iface)
{
const struct batadv_priv *bat_priv = netdev_priv(soft_iface);
const struct batadv_hard_iface *hard_iface;
/* allow big frames if all devices are capable to do so
* (have MTU > 1500 + BAT_HEADER_LEN)
*/
int min_mtu = ETH_DATA_LEN;
if (atomic_read(&bat_priv->fragmentation))
goto out;
rcu_read_lock();
list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
(hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
continue;
if (hard_iface->soft_iface != soft_iface)
continue;
min_mtu = min_t(int,
hard_iface->net_dev->mtu - BATADV_HEADER_LEN,
min_mtu);
}
rcu_read_unlock();
out:
return min_mtu;
}
/* adjusts the MTU if a new interface with a smaller MTU appeared. */
void batadv_update_min_mtu(struct net_device *soft_iface)
{
int min_mtu;
min_mtu = batadv_hardif_min_mtu(soft_iface);
if (soft_iface->mtu != min_mtu)
soft_iface->mtu = min_mtu;
}
static void
batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface)
{
struct batadv_priv *bat_priv;
struct batadv_hard_iface *primary_if = NULL;
if (hard_iface->if_status != BATADV_IF_INACTIVE)
goto out;
bat_priv = netdev_priv(hard_iface->soft_iface);
bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
hard_iface->if_status = BATADV_IF_TO_BE_ACTIVATED;
/* the first active interface becomes our primary interface or
* the next active interface after the old primary interface was removed
*/
primary_if = batadv_primary_if_get_selected(bat_priv);
if (!primary_if)
batadv_primary_if_select(bat_priv, hard_iface);
batadv_info(hard_iface->soft_iface, "Interface activated: %s\n",
hard_iface->net_dev->name);
batadv_update_min_mtu(hard_iface->soft_iface);
out:
if (primary_if)
batadv_hardif_free_ref(primary_if);
}
static void
batadv_hardif_deactivate_interface(struct batadv_hard_iface *hard_iface)
{
if ((hard_iface->if_status != BATADV_IF_ACTIVE) &&
(hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED))
return;
hard_iface->if_status = BATADV_IF_INACTIVE;
batadv_info(hard_iface->soft_iface, "Interface deactivated: %s\n",
hard_iface->net_dev->name);
batadv_update_min_mtu(hard_iface->soft_iface);
}
/**
* batadv_master_del_slave - remove hard_iface from the current master interface
* @slave: the interface enslaved in another master
* @master: the master from which slave has to be removed
*
* Invoke ndo_del_slave on master passing slave as argument. In this way slave
* is free'd and master can correctly change its internal state.
* Return 0 on success, a negative value representing the error otherwise
*/
static int batadv_master_del_slave(struct batadv_hard_iface *slave,
struct net_device *master)
{
int ret;
if (!master)
return 0;
ret = -EBUSY;
if (master->netdev_ops->ndo_del_slave)
ret = master->netdev_ops->ndo_del_slave(master, slave->net_dev);
return ret;
}
int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
const char *iface_name)
{
struct batadv_priv *bat_priv;
struct net_device *soft_iface, *master;
__be16 ethertype = __constant_htons(ETH_P_BATMAN);
int ret;
if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
goto out;
if (!atomic_inc_not_zero(&hard_iface->refcount))
goto out;
soft_iface = dev_get_by_name(&init_net, iface_name);
if (!soft_iface) {
soft_iface = batadv_softif_create(iface_name);
if (!soft_iface) {
ret = -ENOMEM;
goto err;
}
/* dev_get_by_name() increases the reference counter for us */
dev_hold(soft_iface);
}
if (!batadv_softif_is_valid(soft_iface)) {
pr_err("Can't create batman mesh interface %s: already exists as regular interface\n",
soft_iface->name);
ret = -EINVAL;
goto err_dev;
}
/* check if the interface is enslaved in another virtual one and
* in that case unlink it first
*/
master = netdev_master_upper_dev_get(hard_iface->net_dev);
ret = batadv_master_del_slave(hard_iface, master);
if (ret)
goto err_dev;
hard_iface->soft_iface = soft_iface;
bat_priv = netdev_priv(hard_iface->soft_iface);
ret = netdev_master_upper_dev_link(hard_iface->net_dev, soft_iface);
if (ret)
goto err_dev;
ret = bat_priv->bat_algo_ops->bat_iface_enable(hard_iface);
if (ret < 0)
goto err_upper;
hard_iface->if_num = bat_priv->num_ifaces;
bat_priv->num_ifaces++;
hard_iface->if_status = BATADV_IF_INACTIVE;
ret = batadv_orig_hash_add_if(hard_iface, bat_priv->num_ifaces);
if (ret < 0) {
bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
bat_priv->num_ifaces--;
hard_iface->if_status = BATADV_IF_NOT_IN_USE;
goto err_upper;
}
hard_iface->batman_adv_ptype.type = ethertype;
hard_iface->batman_adv_ptype.func = batadv_batman_skb_recv;
hard_iface->batman_adv_ptype.dev = hard_iface->net_dev;
dev_add_pack(&hard_iface->batman_adv_ptype);
atomic_set(&hard_iface->frag_seqno, 1);
batadv_info(hard_iface->soft_iface, "Adding interface: %s\n",
hard_iface->net_dev->name);
if (atomic_read(&bat_priv->fragmentation) &&
hard_iface->net_dev->mtu < ETH_DATA_LEN + BATADV_HEADER_LEN)
batadv_info(hard_iface->soft_iface,
"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 %zi would solve the problem.\n",
hard_iface->net_dev->name, hard_iface->net_dev->mtu,
ETH_DATA_LEN + BATADV_HEADER_LEN);
if (!atomic_read(&bat_priv->fragmentation) &&
hard_iface->net_dev->mtu < ETH_DATA_LEN + BATADV_HEADER_LEN)
batadv_info(hard_iface->soft_iface,
"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 %zi.\n",
hard_iface->net_dev->name, hard_iface->net_dev->mtu,
ETH_DATA_LEN + BATADV_HEADER_LEN);
if (batadv_hardif_is_iface_up(hard_iface))
batadv_hardif_activate_interface(hard_iface);
else
batadv_err(hard_iface->soft_iface,
"Not using interface %s (retrying later): interface not active\n",
hard_iface->net_dev->name);
/* begin scheduling originator messages on that interface */
batadv_schedule_bat_ogm(hard_iface);
out:
return 0;
err_upper:
netdev_upper_dev_unlink(hard_iface->net_dev, soft_iface);
err_dev:
hard_iface->soft_iface = NULL;
dev_put(soft_iface);
err:
batadv_hardif_free_ref(hard_iface);
return ret;
}
void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
enum batadv_hard_if_cleanup autodel)
{
struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
struct batadv_hard_iface *primary_if = NULL;
if (hard_iface->if_status == BATADV_IF_ACTIVE)
batadv_hardif_deactivate_interface(hard_iface);
if (hard_iface->if_status != BATADV_IF_INACTIVE)
goto out;
batadv_info(hard_iface->soft_iface, "Removing interface: %s\n",
hard_iface->net_dev->name);
dev_remove_pack(&hard_iface->batman_adv_ptype);
bat_priv->num_ifaces--;
batadv_orig_hash_del_if(hard_iface, bat_priv->num_ifaces);
primary_if = batadv_primary_if_get_selected(bat_priv);
if (hard_iface == primary_if) {
struct batadv_hard_iface *new_if;
new_if = batadv_hardif_get_active(hard_iface->soft_iface);
batadv_primary_if_select(bat_priv, new_if);
if (new_if)
batadv_hardif_free_ref(new_if);
}
bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
hard_iface->if_status = BATADV_IF_NOT_IN_USE;
/* delete all references to this hard_iface */
batadv_purge_orig_ref(bat_priv);
batadv_purge_outstanding_packets(bat_priv, hard_iface);
dev_put(hard_iface->soft_iface);
/* nobody uses this interface anymore */
if (!bat_priv->num_ifaces && autodel == BATADV_IF_CLEANUP_AUTO)
batadv_softif_destroy_sysfs(hard_iface->soft_iface);
netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);
hard_iface->soft_iface = NULL;
batadv_hardif_free_ref(hard_iface);
out:
if (primary_if)
batadv_hardif_free_ref(primary_if);
}
/**
* batadv_hardif_remove_interface_finish - cleans up the remains of a hardif
* @work: work queue item
*
* Free the parts of the hard interface which can not be removed under
* rtnl lock (to prevent deadlock situations).
*/
static void batadv_hardif_remove_interface_finish(struct work_struct *work)
{
struct batadv_hard_iface *hard_iface;
hard_iface = container_of(work, struct batadv_hard_iface,
cleanup_work);
batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
batadv_hardif_free_ref(hard_iface);
}
static struct batadv_hard_iface *
batadv_hardif_add_interface(struct net_device *net_dev)
{
struct batadv_hard_iface *hard_iface;
int ret;
ASSERT_RTNL();
ret = batadv_is_valid_iface(net_dev);
if (ret != 1)
goto out;
dev_hold(net_dev);
hard_iface = kmalloc(sizeof(*hard_iface), GFP_ATOMIC);
if (!hard_iface)
goto release_dev;
ret = batadv_sysfs_add_hardif(&hard_iface->hardif_obj, net_dev);
if (ret)
goto free_if;
hard_iface->if_num = -1;
hard_iface->net_dev = net_dev;
hard_iface->soft_iface = NULL;
hard_iface->if_status = BATADV_IF_NOT_IN_USE;
INIT_LIST_HEAD(&hard_iface->list);
INIT_WORK(&hard_iface->cleanup_work,
batadv_hardif_remove_interface_finish);
/* extra reference for return */
atomic_set(&hard_iface->refcount, 2);
batadv_check_known_mac_addr(hard_iface->net_dev);
list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);
/* This can't be called via a bat_priv callback because
* we have no bat_priv yet.
*/
atomic_set(&hard_iface->bat_iv.ogm_seqno, 1);
hard_iface->bat_iv.ogm_buff = NULL;
return hard_iface;
free_if:
kfree(hard_iface);
release_dev:
dev_put(net_dev);
out:
return NULL;
}
static void batadv_hardif_remove_interface(struct batadv_hard_iface *hard_iface)
{
ASSERT_RTNL();
/* first deactivate interface */
if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
batadv_hardif_disable_interface(hard_iface,
BATADV_IF_CLEANUP_AUTO);
if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
return;
hard_iface->if_status = BATADV_IF_TO_BE_REMOVED;
queue_work(batadv_event_workqueue, &hard_iface->cleanup_work);
}
void batadv_hardif_remove_interfaces(void)
{
struct batadv_hard_iface *hard_iface, *hard_iface_tmp;
rtnl_lock();
list_for_each_entry_safe(hard_iface, hard_iface_tmp,
&batadv_hardif_list, list) {
list_del_rcu(&hard_iface->list);
batadv_hardif_remove_interface(hard_iface);
}
rtnl_unlock();
}
static int batadv_hard_if_event(struct notifier_block *this,
unsigned long event, void *ptr)
{
struct net_device *net_dev = ptr;
struct batadv_hard_iface *hard_iface;
struct batadv_hard_iface *primary_if = NULL;
struct batadv_priv *bat_priv;
if (batadv_softif_is_valid(net_dev) && event == NETDEV_REGISTER) {
batadv_sysfs_add_meshif(net_dev);
return NOTIFY_DONE;
}
hard_iface = batadv_hardif_get_by_netdev(net_dev);
if (!hard_iface && event == NETDEV_REGISTER)
hard_iface = batadv_hardif_add_interface(net_dev);
if (!hard_iface)
goto out;
switch (event) {
case NETDEV_UP:
batadv_hardif_activate_interface(hard_iface);
break;
case NETDEV_GOING_DOWN:
case NETDEV_DOWN:
batadv_hardif_deactivate_interface(hard_iface);
break;
case NETDEV_UNREGISTER:
list_del_rcu(&hard_iface->list);
batadv_hardif_remove_interface(hard_iface);
break;
case NETDEV_CHANGEMTU:
if (hard_iface->soft_iface)
batadv_update_min_mtu(hard_iface->soft_iface);
break;
case NETDEV_CHANGEADDR:
if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
goto hardif_put;
batadv_check_known_mac_addr(hard_iface->net_dev);
bat_priv = netdev_priv(hard_iface->soft_iface);
bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
primary_if = batadv_primary_if_get_selected(bat_priv);
if (!primary_if)
goto hardif_put;
if (hard_iface == primary_if)
batadv_primary_if_update_addr(bat_priv, NULL);
break;
default:
break;
}
hardif_put:
batadv_hardif_free_ref(hard_iface);
out:
if (primary_if)
batadv_hardif_free_ref(primary_if);
return NOTIFY_DONE;
}
/* This function returns true if the interface represented by ifindex is a
* 802.11 wireless device
*/
bool batadv_is_wifi_iface(int ifindex)
{
struct net_device *net_device = NULL;
bool ret = false;
if (ifindex == BATADV_NULL_IFINDEX)
goto out;
net_device = dev_get_by_index(&init_net, ifindex);
if (!net_device)
goto out;
#ifdef CONFIG_WIRELESS_EXT
/* pre-cfg80211 drivers have to implement WEXT, so it is possible to
* check for wireless_handlers != NULL
*/
if (net_device->wireless_handlers)
ret = true;
else
#endif
/* cfg80211 drivers have to set ieee80211_ptr */
if (net_device->ieee80211_ptr)
ret = true;
out:
if (net_device)
dev_put(net_device);
return ret;
}
struct notifier_block batadv_hard_if_notifier = {
.notifier_call = batadv_hard_if_event,
};
