linux/net/batman-adv/hard-interface.c

1106 lines
30 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2007-2018 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, see <http://www.gnu.org/licenses/>.
*/
#include "hard-interface.h"
#include "main.h"
#include <linux/atomic.h>
#include <linux/bug.h>
#include <linux/byteorder/generic.h>
#include <linux/errno.h>
#include <linux/gfp.h>
#include <linux/if.h>
#include <linux/if_arp.h>
#include <linux/if_ether.h>
#include <linux/kernel.h>
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/netdevice.h>
#include <linux/printk.h>
#include <linux/rculist.h>
#include <linux/rtnetlink.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <net/net_namespace.h>
#include <net/rtnetlink.h>
#include <uapi/linux/batadv_packet.h>
#include "bat_v.h"
#include "bridge_loop_avoidance.h"
#include "debugfs.h"
#include "distributed-arp-table.h"
#include "gateway_client.h"
#include "log.h"
#include "originator.h"
#include "send.h"
#include "soft-interface.h"
#include "sysfs.h"
#include "translation-table.h"
/**
* batadv_hardif_release() - release hard interface from lists and queue for
* free after rcu grace period
* @ref: kref pointer of the hard interface
*/
void batadv_hardif_release(struct kref *ref)
{
struct batadv_hard_iface *hard_iface;
hard_iface = container_of(ref, struct batadv_hard_iface, refcount);
dev_put(hard_iface->net_dev);
kfree_rcu(hard_iface, rcu);
}
/**
* batadv_hardif_get_by_netdev() - Get hard interface object of a net_device
* @net_dev: net_device to search for
*
* Return: batadv_hard_iface of net_dev (with increased refcnt), NULL on errors
*/
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 &&
kref_get_unless_zero(&hard_iface->refcount))
goto out;
}
hard_iface = NULL;
out:
rcu_read_unlock();
return hard_iface;
}
/**
* batadv_getlink_net() - return link net namespace (of use fallback)
* @netdev: net_device to check
* @fallback_net: return in case get_link_net is not available for @netdev
*
* Return: result of rtnl_link_ops->get_link_net or @fallback_net
*/
static struct net *batadv_getlink_net(const struct net_device *netdev,
struct net *fallback_net)
{
if (!netdev->rtnl_link_ops)
return fallback_net;
if (!netdev->rtnl_link_ops->get_link_net)
return fallback_net;
return netdev->rtnl_link_ops->get_link_net(netdev);
}
/**
* batadv_mutual_parents() - check if two devices are each others parent
* @dev1: 1st net dev
* @net1: 1st devices netns
* @dev2: 2nd net dev
* @net2: 2nd devices netns
*
* veth devices come in pairs and each is the parent of the other!
*
* Return: true if the devices are each others parent, otherwise false
*/
static bool batadv_mutual_parents(const struct net_device *dev1,
struct net *net1,
const struct net_device *dev2,
struct net *net2)
{
int dev1_parent_iflink = dev_get_iflink(dev1);
int dev2_parent_iflink = dev_get_iflink(dev2);
const struct net *dev1_parent_net;
const struct net *dev2_parent_net;
dev1_parent_net = batadv_getlink_net(dev1, net1);
dev2_parent_net = batadv_getlink_net(dev2, net2);
if (!dev1_parent_iflink || !dev2_parent_iflink)
return false;
return (dev1_parent_iflink == dev2->ifindex) &&
(dev2_parent_iflink == dev1->ifindex) &&
net_eq(dev1_parent_net, net2) &&
net_eq(dev2_parent_net, net1);
}
/**
* 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.
*
* Return: 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 *net = dev_net(net_dev);
struct net_device *parent_dev;
struct net *parent_net;
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 (dev_get_iflink(net_dev) == 0 ||
dev_get_iflink(net_dev) == net_dev->ifindex)
return false;
parent_net = batadv_getlink_net(net_dev, net);
/* recurse over the parent device */
parent_dev = __dev_get_by_index((struct net *)parent_net,
dev_get_iflink(net_dev));
/* if we got a NULL parent_dev there is something broken.. */
if (WARN(!parent_dev, "Cannot find parent device"))
return false;
if (batadv_mutual_parents(net_dev, net, parent_dev, parent_net))
return false;
ret = batadv_is_on_batman_iface(parent_dev);
return ret;
}
static bool batadv_is_valid_iface(const struct net_device *net_dev)
{
if (net_dev->flags & IFF_LOOPBACK)
return false;
if (net_dev->type != ARPHRD_ETHER)
return false;
if (net_dev->addr_len != ETH_ALEN)
return false;
/* no batman over batman */
if (batadv_is_on_batman_iface(net_dev))
return false;
return true;
}
/**
* batadv_get_real_netdevice() - check if the given netdev struct is a virtual
* interface on top of another 'real' interface
* @netdev: the device to check
*
* Callers must hold the rtnl semaphore. You may want batadv_get_real_netdev()
* instead of this.
*
* Return: the 'real' net device or the original net device and NULL in case
* of an error.
*/
static struct net_device *batadv_get_real_netdevice(struct net_device *netdev)
{
struct batadv_hard_iface *hard_iface = NULL;
struct net_device *real_netdev = NULL;
struct net *real_net;
struct net *net;
int ifindex;
ASSERT_RTNL();
if (!netdev)
return NULL;
if (netdev->ifindex == dev_get_iflink(netdev)) {
dev_hold(netdev);
return netdev;
}
hard_iface = batadv_hardif_get_by_netdev(netdev);
if (!hard_iface || !hard_iface->soft_iface)
goto out;
net = dev_net(hard_iface->soft_iface);
ifindex = dev_get_iflink(netdev);
real_net = batadv_getlink_net(netdev, net);
real_netdev = dev_get_by_index(real_net, ifindex);
out:
if (hard_iface)
batadv_hardif_put(hard_iface);
return real_netdev;
}
/**
* batadv_get_real_netdev() - check if the given net_device struct is a virtual
* interface on top of another 'real' interface
* @net_device: the device to check
*
* Return: the 'real' net device or the original net device and NULL in case
* of an error.
*/
struct net_device *batadv_get_real_netdev(struct net_device *net_device)
{
struct net_device *real_netdev;
rtnl_lock();
real_netdev = batadv_get_real_netdevice(net_device);
rtnl_unlock();
return real_netdev;
}
/**
* batadv_is_wext_netdev() - check if the given net_device struct is a
* wext wifi interface
* @net_device: the device to check
*
* Return: true if the net device is a wext wireless device, false
* otherwise.
*/
static bool batadv_is_wext_netdev(struct net_device *net_device)
{
if (!net_device)
return false;
#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)
return true;
#endif
return false;
}
/**
* batadv_is_cfg80211_netdev() - check if the given net_device struct is a
* cfg80211 wifi interface
* @net_device: the device to check
*
* Return: true if the net device is a cfg80211 wireless device, false
* otherwise.
*/
static bool batadv_is_cfg80211_netdev(struct net_device *net_device)
{
if (!net_device)
return false;
/* cfg80211 drivers have to set ieee80211_ptr */
if (net_device->ieee80211_ptr)
return true;
return false;
}
/**
* batadv_wifi_flags_evaluate() - calculate wifi flags for net_device
* @net_device: the device to check
*
* Return: batadv_hard_iface_wifi_flags flags of the device
*/
static u32 batadv_wifi_flags_evaluate(struct net_device *net_device)
{
u32 wifi_flags = 0;
struct net_device *real_netdev;
if (batadv_is_wext_netdev(net_device))
wifi_flags |= BATADV_HARDIF_WIFI_WEXT_DIRECT;
if (batadv_is_cfg80211_netdev(net_device))
wifi_flags |= BATADV_HARDIF_WIFI_CFG80211_DIRECT;
real_netdev = batadv_get_real_netdevice(net_device);
if (!real_netdev)
return wifi_flags;
if (real_netdev == net_device)
goto out;
if (batadv_is_wext_netdev(real_netdev))
wifi_flags |= BATADV_HARDIF_WIFI_WEXT_INDIRECT;
if (batadv_is_cfg80211_netdev(real_netdev))
wifi_flags |= BATADV_HARDIF_WIFI_CFG80211_INDIRECT;
out:
dev_put(real_netdev);
return wifi_flags;
}
/**
* batadv_is_cfg80211_hardif() - check if the given hardif is a cfg80211 wifi
* interface
* @hard_iface: the device to check
*
* Return: true if the net device is a cfg80211 wireless device, false
* otherwise.
*/
bool batadv_is_cfg80211_hardif(struct batadv_hard_iface *hard_iface)
{
u32 allowed_flags = 0;
allowed_flags |= BATADV_HARDIF_WIFI_CFG80211_DIRECT;
allowed_flags |= BATADV_HARDIF_WIFI_CFG80211_INDIRECT;
return !!(hard_iface->wifi_flags & allowed_flags);
}
/**
* batadv_is_wifi_hardif() - check if the given hardif is a wifi interface
* @hard_iface: the device to check
*
* Return: true if the net device is a 802.11 wireless device, false otherwise.
*/
bool batadv_is_wifi_hardif(struct batadv_hard_iface *hard_iface)
{
if (!hard_iface)
return false;
return hard_iface->wifi_flags != 0;
}
/**
* batadv_hardif_no_broadcast() - check whether (re)broadcast is necessary
* @if_outgoing: the outgoing interface checked and considered for (re)broadcast
* @orig_addr: the originator of this packet
* @orig_neigh: originator address of the forwarder we just got the packet from
* (NULL if we originated)
*
* Checks whether a packet needs to be (re)broadcasted on the given interface.
*
* Return:
* BATADV_HARDIF_BCAST_NORECIPIENT: No neighbor on interface
* BATADV_HARDIF_BCAST_DUPFWD: Just one neighbor, but it is the forwarder
* BATADV_HARDIF_BCAST_DUPORIG: Just one neighbor, but it is the originator
* BATADV_HARDIF_BCAST_OK: Several neighbors, must broadcast
*/
int batadv_hardif_no_broadcast(struct batadv_hard_iface *if_outgoing,
u8 *orig_addr, u8 *orig_neigh)
{
struct batadv_hardif_neigh_node *hardif_neigh;
struct hlist_node *first;
int ret = BATADV_HARDIF_BCAST_OK;
rcu_read_lock();
/* 0 neighbors -> no (re)broadcast */
first = rcu_dereference(hlist_first_rcu(&if_outgoing->neigh_list));
if (!first) {
ret = BATADV_HARDIF_BCAST_NORECIPIENT;
goto out;
}
/* >1 neighbors -> (re)brodcast */
if (rcu_dereference(hlist_next_rcu(first)))
goto out;
hardif_neigh = hlist_entry(first, struct batadv_hardif_neigh_node,
list);
/* 1 neighbor, is the originator -> no rebroadcast */
if (orig_addr && batadv_compare_eth(hardif_neigh->orig, orig_addr)) {
ret = BATADV_HARDIF_BCAST_DUPORIG;
/* 1 neighbor, is the one we received from -> no rebroadcast */
} else if (orig_neigh &&
batadv_compare_eth(hardif_neigh->orig, orig_neigh)) {
ret = BATADV_HARDIF_BCAST_DUPFWD;
}
out:
rcu_read_unlock();
return ret;
}
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 &&
kref_get_unless_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_hard_iface *primary_if;
primary_if = batadv_primary_if_get_selected(bat_priv);
if (!primary_if)
goto out;
batadv_dat_init_own_addr(bat_priv, primary_if);
batadv_bla_update_orig_address(bat_priv, primary_if, oldif);
out:
if (primary_if)
batadv_hardif_put(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)
kref_get(&new_hard_iface->refcount);
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->algo_ops->iface.primary_set(new_hard_iface);
batadv_primary_if_update_addr(bat_priv, curr_hard_iface);
out:
if (curr_hard_iface)
batadv_hardif_put(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();
}
/**
* batadv_hardif_recalc_extra_skbroom() - Recalculate skbuff extra head/tailroom
* @soft_iface: netdev struct of the mesh interface
*/
static void batadv_hardif_recalc_extra_skbroom(struct net_device *soft_iface)
{
const struct batadv_hard_iface *hard_iface;
unsigned short lower_header_len = ETH_HLEN;
unsigned short lower_headroom = 0;
unsigned short lower_tailroom = 0;
unsigned short needed_headroom;
rcu_read_lock();
list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
continue;
if (hard_iface->soft_iface != soft_iface)
continue;
lower_header_len = max_t(unsigned short, lower_header_len,
hard_iface->net_dev->hard_header_len);
lower_headroom = max_t(unsigned short, lower_headroom,
hard_iface->net_dev->needed_headroom);
lower_tailroom = max_t(unsigned short, lower_tailroom,
hard_iface->net_dev->needed_tailroom);
}
rcu_read_unlock();
needed_headroom = lower_headroom + (lower_header_len - ETH_HLEN);
needed_headroom += batadv_max_header_len();
soft_iface->needed_headroom = needed_headroom;
soft_iface->needed_tailroom = lower_tailroom;
}
/**
* batadv_hardif_min_mtu() - Calculate maximum MTU for soft interface
* @soft_iface: netdev struct of the soft interface
*
* Return: MTU for the soft-interface (limited by the minimal MTU of all active
* slave interfaces)
*/
int batadv_hardif_min_mtu(struct net_device *soft_iface)
{
struct batadv_priv *bat_priv = netdev_priv(soft_iface);
const struct batadv_hard_iface *hard_iface;
int min_mtu = INT_MAX;
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, min_mtu);
}
rcu_read_unlock();
if (atomic_read(&bat_priv->fragmentation) == 0)
goto out;
/* with fragmentation enabled the maximum size of internally generated
* packets such as translation table exchanges or tvlv containers, etc
* has to be calculated
*/
min_mtu = min_t(int, min_mtu, BATADV_FRAG_MAX_FRAG_SIZE);
min_mtu -= sizeof(struct batadv_frag_packet);
min_mtu *= BATADV_FRAG_MAX_FRAGMENTS;
out:
/* report to the other components the maximum amount of bytes that
* batman-adv can send over the wire (without considering the payload
* overhead). For example, this value is used by TT to compute the
* maximum local table table size
*/
atomic_set(&bat_priv->packet_size_max, min_mtu);
/* the real soft-interface MTU is computed by removing the payload
* overhead from the maximum amount of bytes that was just computed.
*
* However batman-adv does not support MTUs bigger than ETH_DATA_LEN
*/
return min_t(int, min_mtu - batadv_max_header_len(), ETH_DATA_LEN);
}
/**
* batadv_update_min_mtu() - Adjusts the MTU if a new interface with a smaller
* MTU appeared
* @soft_iface: netdev struct of the soft interface
*/
void batadv_update_min_mtu(struct net_device *soft_iface)
{
soft_iface->mtu = batadv_hardif_min_mtu(soft_iface);
/* Check if the local translate table should be cleaned up to match a
* new (and smaller) MTU.
*/
batadv_tt_local_resize_to_mtu(soft_iface);
}
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->algo_ops->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);
if (bat_priv->algo_ops->iface.activate)
bat_priv->algo_ops->iface.activate(hard_iface);
out:
if (primary_if)
batadv_hardif_put(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 iface
* @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;
}
/**
* batadv_hardif_enable_interface() - Enslave hard interface to soft interface
* @hard_iface: hard interface to add to soft interface
* @net: the applicable net namespace
* @iface_name: name of the soft interface
*
* Return: 0 on success or negative error number in case of failure
*/
int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
struct net *net, const char *iface_name)
{
struct batadv_priv *bat_priv;
struct net_device *soft_iface, *master;
__be16 ethertype = htons(ETH_P_BATMAN);
int max_header_len = batadv_max_header_len();
int ret;
if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
goto out;
kref_get(&hard_iface->refcount);
soft_iface = dev_get_by_name(net, iface_name);
if (!soft_iface) {
soft_iface = batadv_softif_create(net, 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, NULL, NULL, NULL);
if (ret)
goto err_dev;
ret = bat_priv->algo_ops->iface.enable(hard_iface);
if (ret < 0)
goto err_upper;
hard_iface->if_status = BATADV_IF_INACTIVE;
kref_get(&hard_iface->refcount);
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);
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 + max_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 %i would solve the problem.\n",
hard_iface->net_dev->name, hard_iface->net_dev->mtu,
ETH_DATA_LEN + max_header_len);
if (!atomic_read(&bat_priv->fragmentation) &&
hard_iface->net_dev->mtu < ETH_DATA_LEN + max_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 %i.\n",
hard_iface->net_dev->name, hard_iface->net_dev->mtu,
ETH_DATA_LEN + max_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);
batadv_hardif_recalc_extra_skbroom(soft_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_put(hard_iface);
return ret;
}
/**
* batadv_hardif_cnt() - get number of interfaces enslaved to soft interface
* @soft_iface: soft interface to check
*
* This function is only using RCU for locking - the result can therefore be
* off when another functions is modifying the list at the same time. The
* caller can use the rtnl_lock to make sure that the count is accurate.
*
* Return: number of connected/enslaved hard interfaces
*/
static size_t batadv_hardif_cnt(const struct net_device *soft_iface)
{
struct batadv_hard_iface *hard_iface;
size_t count = 0;
rcu_read_lock();
list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
if (hard_iface->soft_iface != soft_iface)
continue;
count++;
}
rcu_read_unlock();
return count;
}
/**
* batadv_hardif_disable_interface() - Remove hard interface from soft interface
* @hard_iface: hard interface to be removed
* @autodel: whether to delete soft interface when it doesn't contain any other
* slave interfaces
*/
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;
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);
batadv_hardif_put(hard_iface);
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_put(new_if);
}
bat_priv->algo_ops->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);
netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);
batadv_hardif_recalc_extra_skbroom(hard_iface->soft_iface);
/* nobody uses this interface anymore */
if (batadv_hardif_cnt(hard_iface->soft_iface) <= 1) {
batadv_gw_check_client_stop(bat_priv);
if (autodel == BATADV_IF_CLEANUP_AUTO)
batadv_softif_destroy_sysfs(hard_iface->soft_iface);
}
hard_iface->soft_iface = NULL;
batadv_hardif_put(hard_iface);
out:
if (primary_if)
batadv_hardif_put(primary_if);
}
static struct batadv_hard_iface *
batadv_hardif_add_interface(struct net_device *net_dev)
{
struct batadv_hard_iface *hard_iface;
int ret;
ASSERT_RTNL();
if (!batadv_is_valid_iface(net_dev))
goto out;
dev_hold(net_dev);
hard_iface = kzalloc(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->net_dev = net_dev;
hard_iface->soft_iface = NULL;
hard_iface->if_status = BATADV_IF_NOT_IN_USE;
ret = batadv_debugfs_add_hardif(hard_iface);
if (ret)
goto free_sysfs;
INIT_LIST_HEAD(&hard_iface->list);
INIT_HLIST_HEAD(&hard_iface->neigh_list);
spin_lock_init(&hard_iface->neigh_list_lock);
kref_init(&hard_iface->refcount);
hard_iface->num_bcasts = BATADV_NUM_BCASTS_DEFAULT;
hard_iface->wifi_flags = batadv_wifi_flags_evaluate(net_dev);
if (batadv_is_wifi_hardif(hard_iface))
hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS;
batadv_v_hardif_init(hard_iface);
batadv_check_known_mac_addr(hard_iface->net_dev);
kref_get(&hard_iface->refcount);
list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);
batadv_hardif_generation++;
return hard_iface;
free_sysfs:
batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
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_KEEP);
if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
return;
hard_iface->if_status = BATADV_IF_TO_BE_REMOVED;
batadv_debugfs_del_hardif(hard_iface);
batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
batadv_hardif_put(hard_iface);
}
/**
* batadv_hardif_remove_interfaces() - Remove all hard interfaces
*/
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_generation++;
batadv_hardif_remove_interface(hard_iface);
}
rtnl_unlock();
}
/**
* batadv_hard_if_event_softif() - Handle events for soft interfaces
* @event: NETDEV_* event to handle
* @net_dev: net_device which generated an event
*
* Return: NOTIFY_* result
*/
static int batadv_hard_if_event_softif(unsigned long event,
struct net_device *net_dev)
{
struct batadv_priv *bat_priv;
switch (event) {
case NETDEV_REGISTER:
batadv_sysfs_add_meshif(net_dev);
bat_priv = netdev_priv(net_dev);
batadv_softif_create_vlan(bat_priv, BATADV_NO_FLAGS);
break;
case NETDEV_CHANGENAME:
batadv_debugfs_rename_meshif(net_dev);
break;
}
return NOTIFY_DONE;
}
static int batadv_hard_if_event(struct notifier_block *this,
unsigned long event, void *ptr)
{
struct net_device *net_dev = netdev_notifier_info_to_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))
return batadv_hard_if_event_softif(event, net_dev);
hard_iface = batadv_hardif_get_by_netdev(net_dev);
if (!hard_iface && (event == NETDEV_REGISTER ||
event == NETDEV_POST_TYPE_CHANGE))
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:
case NETDEV_PRE_TYPE_CHANGE:
list_del_rcu(&hard_iface->list);
batadv_hardif_generation++;
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->algo_ops->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;
case NETDEV_CHANGEUPPER:
hard_iface->wifi_flags = batadv_wifi_flags_evaluate(net_dev);
if (batadv_is_wifi_hardif(hard_iface))
hard_iface->num_bcasts = BATADV_NUM_BCASTS_WIRELESS;
break;
case NETDEV_CHANGENAME:
batadv_debugfs_rename_hardif(hard_iface);
break;
default:
break;
}
hardif_put:
batadv_hardif_put(hard_iface);
out:
if (primary_if)
batadv_hardif_put(primary_if);
return NOTIFY_DONE;
}
struct notifier_block batadv_hard_if_notifier = {
.notifier_call = batadv_hard_if_event,
};