linux_dsm_epyc7002/net/batman-adv/hard-interface.c
Antonio Quartulli cb4b0d4864 batman-adv: free an hard-interface before adding it
When adding a new hard interface (e.g. wlan0) to a soft interface (e.g. bat0)
and the former is already enslaved in another virtual interface (e.g. a software
bridge) batman-adv has to free it first and then continue with the adding
mechanism.

In this way the behaviour becomes consistent with what "ip link set master"
does. At the moment batman-adv enslaves the hard interface without checking for
the master device, possibly causing strange behaviours which are never wanted by
the users.

Reported-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2013-03-27 10:29:53 +01:00

695 lines
18 KiB
C

/* 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,
};