linux/net/batman-adv/multicast.c
Sven Eckelmann 5274cd68d7 batman-adv: Add lockdep_asserts for documented external locks
Some functions already have documentation about locks they require inside
their kerneldoc header. These can be directly tested during runtime using
the lockdep asserts.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
2015-08-25 00:12:23 +02:00

828 lines
25 KiB
C

/* Copyright (C) 2014-2015 B.A.T.M.A.N. contributors:
*
* Linus Lüssing
*
* 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 "multicast.h"
#include "main.h"
#include <linux/atomic.h>
#include <linux/bitops.h>
#include <linux/bug.h>
#include <linux/byteorder/generic.h>
#include <linux/errno.h>
#include <linux/etherdevice.h>
#include <linux/fs.h>
#include <linux/if_ether.h>
#include <linux/in6.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/list.h>
#include <linux/lockdep.h>
#include <linux/netdevice.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <linux/types.h>
#include <net/addrconf.h>
#include <net/ipv6.h>
#include "packet.h"
#include "translation-table.h"
/**
* batadv_mcast_mla_softif_get - get softif multicast listeners
* @dev: the device to collect multicast addresses from
* @mcast_list: a list to put found addresses into
*
* Collect multicast addresses of the local multicast listeners
* on the given soft interface, dev, in the given mcast_list.
*
* Returns -ENOMEM on memory allocation error or the number of
* items added to the mcast_list otherwise.
*/
static int batadv_mcast_mla_softif_get(struct net_device *dev,
struct hlist_head *mcast_list)
{
struct netdev_hw_addr *mc_list_entry;
struct batadv_hw_addr *new;
int ret = 0;
netif_addr_lock_bh(dev);
netdev_for_each_mc_addr(mc_list_entry, dev) {
new = kmalloc(sizeof(*new), GFP_ATOMIC);
if (!new) {
ret = -ENOMEM;
break;
}
ether_addr_copy(new->addr, mc_list_entry->addr);
hlist_add_head(&new->list, mcast_list);
ret++;
}
netif_addr_unlock_bh(dev);
return ret;
}
/**
* batadv_mcast_mla_is_duplicate - check whether an address is in a list
* @mcast_addr: the multicast address to check
* @mcast_list: the list with multicast addresses to search in
*
* Returns true if the given address is already in the given list.
* Otherwise returns false.
*/
static bool batadv_mcast_mla_is_duplicate(u8 *mcast_addr,
struct hlist_head *mcast_list)
{
struct batadv_hw_addr *mcast_entry;
hlist_for_each_entry(mcast_entry, mcast_list, list)
if (batadv_compare_eth(mcast_entry->addr, mcast_addr))
return true;
return false;
}
/**
* batadv_mcast_mla_list_free - free a list of multicast addresses
* @bat_priv: the bat priv with all the soft interface information
* @mcast_list: the list to free
*
* Removes and frees all items in the given mcast_list.
*/
static void batadv_mcast_mla_list_free(struct batadv_priv *bat_priv,
struct hlist_head *mcast_list)
{
struct batadv_hw_addr *mcast_entry;
struct hlist_node *tmp;
lockdep_assert_held(&bat_priv->tt.commit_lock);
hlist_for_each_entry_safe(mcast_entry, tmp, mcast_list, list) {
hlist_del(&mcast_entry->list);
kfree(mcast_entry);
}
}
/**
* batadv_mcast_mla_tt_retract - clean up multicast listener announcements
* @bat_priv: the bat priv with all the soft interface information
* @mcast_list: a list of addresses which should _not_ be removed
*
* Retracts the announcement of any multicast listener from the
* translation table except the ones listed in the given mcast_list.
*
* If mcast_list is NULL then all are retracted.
*/
static void batadv_mcast_mla_tt_retract(struct batadv_priv *bat_priv,
struct hlist_head *mcast_list)
{
struct batadv_hw_addr *mcast_entry;
struct hlist_node *tmp;
lockdep_assert_held(&bat_priv->tt.commit_lock);
hlist_for_each_entry_safe(mcast_entry, tmp, &bat_priv->mcast.mla_list,
list) {
if (mcast_list &&
batadv_mcast_mla_is_duplicate(mcast_entry->addr,
mcast_list))
continue;
batadv_tt_local_remove(bat_priv, mcast_entry->addr,
BATADV_NO_FLAGS,
"mcast TT outdated", false);
hlist_del(&mcast_entry->list);
kfree(mcast_entry);
}
}
/**
* batadv_mcast_mla_tt_add - add multicast listener announcements
* @bat_priv: the bat priv with all the soft interface information
* @mcast_list: a list of addresses which are going to get added
*
* Adds multicast listener announcements from the given mcast_list to the
* translation table if they have not been added yet.
*/
static void batadv_mcast_mla_tt_add(struct batadv_priv *bat_priv,
struct hlist_head *mcast_list)
{
struct batadv_hw_addr *mcast_entry;
struct hlist_node *tmp;
lockdep_assert_held(&bat_priv->tt.commit_lock);
if (!mcast_list)
return;
hlist_for_each_entry_safe(mcast_entry, tmp, mcast_list, list) {
if (batadv_mcast_mla_is_duplicate(mcast_entry->addr,
&bat_priv->mcast.mla_list))
continue;
if (!batadv_tt_local_add(bat_priv->soft_iface,
mcast_entry->addr, BATADV_NO_FLAGS,
BATADV_NULL_IFINDEX, BATADV_NO_MARK))
continue;
hlist_del(&mcast_entry->list);
hlist_add_head(&mcast_entry->list, &bat_priv->mcast.mla_list);
}
}
/**
* batadv_mcast_has_bridge - check whether the soft-iface is bridged
* @bat_priv: the bat priv with all the soft interface information
*
* Checks whether there is a bridge on top of our soft interface. Returns
* true if so, false otherwise.
*/
static bool batadv_mcast_has_bridge(struct batadv_priv *bat_priv)
{
struct net_device *upper = bat_priv->soft_iface;
rcu_read_lock();
do {
upper = netdev_master_upper_dev_get_rcu(upper);
} while (upper && !(upper->priv_flags & IFF_EBRIDGE));
rcu_read_unlock();
return upper;
}
/**
* batadv_mcast_mla_tvlv_update - update multicast tvlv
* @bat_priv: the bat priv with all the soft interface information
*
* Updates the own multicast tvlv with our current multicast related settings,
* capabilities and inabilities.
*
* Returns true if the tvlv container is registered afterwards. Otherwise
* returns false.
*/
static bool batadv_mcast_mla_tvlv_update(struct batadv_priv *bat_priv)
{
struct batadv_tvlv_mcast_data mcast_data;
mcast_data.flags = BATADV_NO_FLAGS;
memset(mcast_data.reserved, 0, sizeof(mcast_data.reserved));
/* Avoid attaching MLAs, if there is a bridge on top of our soft
* interface, we don't support that yet (TODO)
*/
if (batadv_mcast_has_bridge(bat_priv)) {
if (bat_priv->mcast.enabled) {
batadv_tvlv_container_unregister(bat_priv,
BATADV_TVLV_MCAST, 1);
bat_priv->mcast.enabled = false;
}
return false;
}
if (!bat_priv->mcast.enabled ||
mcast_data.flags != bat_priv->mcast.flags) {
batadv_tvlv_container_register(bat_priv, BATADV_TVLV_MCAST, 1,
&mcast_data, sizeof(mcast_data));
bat_priv->mcast.flags = mcast_data.flags;
bat_priv->mcast.enabled = true;
}
return true;
}
/**
* batadv_mcast_mla_update - update the own MLAs
* @bat_priv: the bat priv with all the soft interface information
*
* Updates the own multicast listener announcements in the translation
* table as well as the own, announced multicast tvlv container.
*/
void batadv_mcast_mla_update(struct batadv_priv *bat_priv)
{
struct net_device *soft_iface = bat_priv->soft_iface;
struct hlist_head mcast_list = HLIST_HEAD_INIT;
int ret;
if (!batadv_mcast_mla_tvlv_update(bat_priv))
goto update;
ret = batadv_mcast_mla_softif_get(soft_iface, &mcast_list);
if (ret < 0)
goto out;
update:
batadv_mcast_mla_tt_retract(bat_priv, &mcast_list);
batadv_mcast_mla_tt_add(bat_priv, &mcast_list);
out:
batadv_mcast_mla_list_free(bat_priv, &mcast_list);
}
/**
* batadv_mcast_forw_mode_check_ipv4 - check for optimized forwarding potential
* @bat_priv: the bat priv with all the soft interface information
* @skb: the IPv4 packet to check
* @is_unsnoopable: stores whether the destination is snoopable
*
* Checks whether the given IPv4 packet has the potential to be forwarded with a
* mode more optimal than classic flooding.
*
* If so then returns 0. Otherwise -EINVAL is returned or -ENOMEM in case of
* memory allocation failure.
*/
static int batadv_mcast_forw_mode_check_ipv4(struct batadv_priv *bat_priv,
struct sk_buff *skb,
bool *is_unsnoopable)
{
struct iphdr *iphdr;
/* We might fail due to out-of-memory -> drop it */
if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*iphdr)))
return -ENOMEM;
iphdr = ip_hdr(skb);
/* TODO: Implement Multicast Router Discovery (RFC4286),
* then allow scope > link local, too
*/
if (!ipv4_is_local_multicast(iphdr->daddr))
return -EINVAL;
/* link-local multicast listeners behind a bridge are
* not snoopable (see RFC4541, section 2.1.2.2)
*/
*is_unsnoopable = true;
return 0;
}
/**
* batadv_mcast_forw_mode_check_ipv6 - check for optimized forwarding potential
* @bat_priv: the bat priv with all the soft interface information
* @skb: the IPv6 packet to check
* @is_unsnoopable: stores whether the destination is snoopable
*
* Checks whether the given IPv6 packet has the potential to be forwarded with a
* mode more optimal than classic flooding.
*
* If so then returns 0. Otherwise -EINVAL is returned or -ENOMEM if we are out
* of memory.
*/
static int batadv_mcast_forw_mode_check_ipv6(struct batadv_priv *bat_priv,
struct sk_buff *skb,
bool *is_unsnoopable)
{
struct ipv6hdr *ip6hdr;
/* We might fail due to out-of-memory -> drop it */
if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*ip6hdr)))
return -ENOMEM;
ip6hdr = ipv6_hdr(skb);
/* TODO: Implement Multicast Router Discovery (RFC4286),
* then allow scope > link local, too
*/
if (IPV6_ADDR_MC_SCOPE(&ip6hdr->daddr) != IPV6_ADDR_SCOPE_LINKLOCAL)
return -EINVAL;
/* link-local-all-nodes multicast listeners behind a bridge are
* not snoopable (see RFC4541, section 3, paragraph 3)
*/
if (ipv6_addr_is_ll_all_nodes(&ip6hdr->daddr))
*is_unsnoopable = true;
return 0;
}
/**
* batadv_mcast_forw_mode_check - check for optimized forwarding potential
* @bat_priv: the bat priv with all the soft interface information
* @skb: the multicast frame to check
* @is_unsnoopable: stores whether the destination is snoopable
*
* Checks whether the given multicast ethernet frame has the potential to be
* forwarded with a mode more optimal than classic flooding.
*
* If so then returns 0. Otherwise -EINVAL is returned or -ENOMEM if we are out
* of memory.
*/
static int batadv_mcast_forw_mode_check(struct batadv_priv *bat_priv,
struct sk_buff *skb,
bool *is_unsnoopable)
{
struct ethhdr *ethhdr = eth_hdr(skb);
if (!atomic_read(&bat_priv->multicast_mode))
return -EINVAL;
if (atomic_read(&bat_priv->mcast.num_disabled))
return -EINVAL;
switch (ntohs(ethhdr->h_proto)) {
case ETH_P_IP:
return batadv_mcast_forw_mode_check_ipv4(bat_priv, skb,
is_unsnoopable);
case ETH_P_IPV6:
return batadv_mcast_forw_mode_check_ipv6(bat_priv, skb,
is_unsnoopable);
default:
return -EINVAL;
}
}
/**
* batadv_mcast_want_all_ip_count - count nodes with unspecific mcast interest
* @bat_priv: the bat priv with all the soft interface information
* @ethhdr: ethernet header of a packet
*
* Returns the number of nodes which want all IPv4 multicast traffic if the
* given ethhdr is from an IPv4 packet or the number of nodes which want all
* IPv6 traffic if it matches an IPv6 packet.
*/
static int batadv_mcast_forw_want_all_ip_count(struct batadv_priv *bat_priv,
struct ethhdr *ethhdr)
{
switch (ntohs(ethhdr->h_proto)) {
case ETH_P_IP:
return atomic_read(&bat_priv->mcast.num_want_all_ipv4);
case ETH_P_IPV6:
return atomic_read(&bat_priv->mcast.num_want_all_ipv6);
default:
/* we shouldn't be here... */
return 0;
}
}
/**
* batadv_mcast_forw_tt_node_get - get a multicast tt node
* @bat_priv: the bat priv with all the soft interface information
* @ethhdr: the ether header containing the multicast destination
*
* Returns an orig_node matching the multicast address provided by ethhdr
* via a translation table lookup. This increases the returned nodes refcount.
*/
static struct batadv_orig_node *
batadv_mcast_forw_tt_node_get(struct batadv_priv *bat_priv,
struct ethhdr *ethhdr)
{
return batadv_transtable_search(bat_priv, ethhdr->h_source,
ethhdr->h_dest, BATADV_NO_FLAGS);
}
/**
* batadv_mcast_want_forw_ipv4_node_get - get a node with an ipv4 flag
* @bat_priv: the bat priv with all the soft interface information
*
* Returns an orig_node which has the BATADV_MCAST_WANT_ALL_IPV4 flag set and
* increases its refcount.
*/
static struct batadv_orig_node *
batadv_mcast_forw_ipv4_node_get(struct batadv_priv *bat_priv)
{
struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
rcu_read_lock();
hlist_for_each_entry_rcu(tmp_orig_node,
&bat_priv->mcast.want_all_ipv4_list,
mcast_want_all_ipv4_node) {
if (!atomic_inc_not_zero(&tmp_orig_node->refcount))
continue;
orig_node = tmp_orig_node;
break;
}
rcu_read_unlock();
return orig_node;
}
/**
* batadv_mcast_want_forw_ipv6_node_get - get a node with an ipv6 flag
* @bat_priv: the bat priv with all the soft interface information
*
* Returns an orig_node which has the BATADV_MCAST_WANT_ALL_IPV6 flag set
* and increases its refcount.
*/
static struct batadv_orig_node *
batadv_mcast_forw_ipv6_node_get(struct batadv_priv *bat_priv)
{
struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
rcu_read_lock();
hlist_for_each_entry_rcu(tmp_orig_node,
&bat_priv->mcast.want_all_ipv6_list,
mcast_want_all_ipv6_node) {
if (!atomic_inc_not_zero(&tmp_orig_node->refcount))
continue;
orig_node = tmp_orig_node;
break;
}
rcu_read_unlock();
return orig_node;
}
/**
* batadv_mcast_want_forw_ip_node_get - get a node with an ipv4/ipv6 flag
* @bat_priv: the bat priv with all the soft interface information
* @ethhdr: an ethernet header to determine the protocol family from
*
* Returns an orig_node which has the BATADV_MCAST_WANT_ALL_IPV4 or
* BATADV_MCAST_WANT_ALL_IPV6 flag, depending on the provided ethhdr, set and
* increases its refcount.
*/
static struct batadv_orig_node *
batadv_mcast_forw_ip_node_get(struct batadv_priv *bat_priv,
struct ethhdr *ethhdr)
{
switch (ntohs(ethhdr->h_proto)) {
case ETH_P_IP:
return batadv_mcast_forw_ipv4_node_get(bat_priv);
case ETH_P_IPV6:
return batadv_mcast_forw_ipv6_node_get(bat_priv);
default:
/* we shouldn't be here... */
return NULL;
}
}
/**
* batadv_mcast_want_forw_unsnoop_node_get - get a node with an unsnoopable flag
* @bat_priv: the bat priv with all the soft interface information
*
* Returns an orig_node which has the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag
* set and increases its refcount.
*/
static struct batadv_orig_node *
batadv_mcast_forw_unsnoop_node_get(struct batadv_priv *bat_priv)
{
struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
rcu_read_lock();
hlist_for_each_entry_rcu(tmp_orig_node,
&bat_priv->mcast.want_all_unsnoopables_list,
mcast_want_all_unsnoopables_node) {
if (!atomic_inc_not_zero(&tmp_orig_node->refcount))
continue;
orig_node = tmp_orig_node;
break;
}
rcu_read_unlock();
return orig_node;
}
/**
* batadv_mcast_forw_mode - check on how to forward a multicast packet
* @bat_priv: the bat priv with all the soft interface information
* @skb: The multicast packet to check
* @orig: an originator to be set to forward the skb to
*
* Returns the forwarding mode as enum batadv_forw_mode and in case of
* BATADV_FORW_SINGLE set the orig to the single originator the skb
* should be forwarded to.
*/
enum batadv_forw_mode
batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb,
struct batadv_orig_node **orig)
{
int ret, tt_count, ip_count, unsnoop_count, total_count;
bool is_unsnoopable = false;
struct ethhdr *ethhdr;
ret = batadv_mcast_forw_mode_check(bat_priv, skb, &is_unsnoopable);
if (ret == -ENOMEM)
return BATADV_FORW_NONE;
else if (ret < 0)
return BATADV_FORW_ALL;
ethhdr = eth_hdr(skb);
tt_count = batadv_tt_global_hash_count(bat_priv, ethhdr->h_dest,
BATADV_NO_FLAGS);
ip_count = batadv_mcast_forw_want_all_ip_count(bat_priv, ethhdr);
unsnoop_count = !is_unsnoopable ? 0 :
atomic_read(&bat_priv->mcast.num_want_all_unsnoopables);
total_count = tt_count + ip_count + unsnoop_count;
switch (total_count) {
case 1:
if (tt_count)
*orig = batadv_mcast_forw_tt_node_get(bat_priv, ethhdr);
else if (ip_count)
*orig = batadv_mcast_forw_ip_node_get(bat_priv, ethhdr);
else if (unsnoop_count)
*orig = batadv_mcast_forw_unsnoop_node_get(bat_priv);
if (*orig)
return BATADV_FORW_SINGLE;
/* fall through */
case 0:
return BATADV_FORW_NONE;
default:
return BATADV_FORW_ALL;
}
}
/**
* batadv_mcast_want_unsnoop_update - update unsnoop counter and list
* @bat_priv: the bat priv with all the soft interface information
* @orig: the orig_node which multicast state might have changed of
* @mcast_flags: flags indicating the new multicast state
*
* If the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag of this originator,
* orig, has toggled then this method updates counter and list accordingly.
*
* Caller needs to hold orig->mcast_handler_lock.
*/
static void batadv_mcast_want_unsnoop_update(struct batadv_priv *bat_priv,
struct batadv_orig_node *orig,
u8 mcast_flags)
{
struct hlist_node *node = &orig->mcast_want_all_unsnoopables_node;
struct hlist_head *head = &bat_priv->mcast.want_all_unsnoopables_list;
lockdep_assert_held(&orig->mcast_handler_lock);
/* switched from flag unset to set */
if (mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
!(orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES)) {
atomic_inc(&bat_priv->mcast.num_want_all_unsnoopables);
spin_lock_bh(&bat_priv->mcast.want_lists_lock);
/* flag checks above + mcast_handler_lock prevents this */
WARN_ON(!hlist_unhashed(node));
hlist_add_head_rcu(node, head);
spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
/* switched from flag set to unset */
} else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) &&
orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) {
atomic_dec(&bat_priv->mcast.num_want_all_unsnoopables);
spin_lock_bh(&bat_priv->mcast.want_lists_lock);
/* flag checks above + mcast_handler_lock prevents this */
WARN_ON(hlist_unhashed(node));
hlist_del_init_rcu(node);
spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
}
}
/**
* batadv_mcast_want_ipv4_update - update want-all-ipv4 counter and list
* @bat_priv: the bat priv with all the soft interface information
* @orig: the orig_node which multicast state might have changed of
* @mcast_flags: flags indicating the new multicast state
*
* If the BATADV_MCAST_WANT_ALL_IPV4 flag of this originator, orig, has
* toggled then this method updates counter and list accordingly.
*
* Caller needs to hold orig->mcast_handler_lock.
*/
static void batadv_mcast_want_ipv4_update(struct batadv_priv *bat_priv,
struct batadv_orig_node *orig,
u8 mcast_flags)
{
struct hlist_node *node = &orig->mcast_want_all_ipv4_node;
struct hlist_head *head = &bat_priv->mcast.want_all_ipv4_list;
lockdep_assert_held(&orig->mcast_handler_lock);
/* switched from flag unset to set */
if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV4 &&
!(orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV4)) {
atomic_inc(&bat_priv->mcast.num_want_all_ipv4);
spin_lock_bh(&bat_priv->mcast.want_lists_lock);
/* flag checks above + mcast_handler_lock prevents this */
WARN_ON(!hlist_unhashed(node));
hlist_add_head_rcu(node, head);
spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
/* switched from flag set to unset */
} else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_IPV4) &&
orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV4) {
atomic_dec(&bat_priv->mcast.num_want_all_ipv4);
spin_lock_bh(&bat_priv->mcast.want_lists_lock);
/* flag checks above + mcast_handler_lock prevents this */
WARN_ON(hlist_unhashed(node));
hlist_del_init_rcu(node);
spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
}
}
/**
* batadv_mcast_want_ipv6_update - update want-all-ipv6 counter and list
* @bat_priv: the bat priv with all the soft interface information
* @orig: the orig_node which multicast state might have changed of
* @mcast_flags: flags indicating the new multicast state
*
* If the BATADV_MCAST_WANT_ALL_IPV6 flag of this originator, orig, has
* toggled then this method updates counter and list accordingly.
*
* Caller needs to hold orig->mcast_handler_lock.
*/
static void batadv_mcast_want_ipv6_update(struct batadv_priv *bat_priv,
struct batadv_orig_node *orig,
u8 mcast_flags)
{
struct hlist_node *node = &orig->mcast_want_all_ipv6_node;
struct hlist_head *head = &bat_priv->mcast.want_all_ipv6_list;
lockdep_assert_held(&orig->mcast_handler_lock);
/* switched from flag unset to set */
if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV6 &&
!(orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV6)) {
atomic_inc(&bat_priv->mcast.num_want_all_ipv6);
spin_lock_bh(&bat_priv->mcast.want_lists_lock);
/* flag checks above + mcast_handler_lock prevents this */
WARN_ON(!hlist_unhashed(node));
hlist_add_head_rcu(node, head);
spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
/* switched from flag set to unset */
} else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_IPV6) &&
orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV6) {
atomic_dec(&bat_priv->mcast.num_want_all_ipv6);
spin_lock_bh(&bat_priv->mcast.want_lists_lock);
/* flag checks above + mcast_handler_lock prevents this */
WARN_ON(hlist_unhashed(node));
hlist_del_init_rcu(node);
spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
}
}
/**
* batadv_mcast_tvlv_ogm_handler_v1 - process incoming multicast tvlv container
* @bat_priv: the bat priv with all the soft interface information
* @orig: the orig_node of the ogm
* @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
* @tvlv_value: tvlv buffer containing the multicast data
* @tvlv_value_len: tvlv buffer length
*/
static void batadv_mcast_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
struct batadv_orig_node *orig,
u8 flags,
void *tvlv_value,
u16 tvlv_value_len)
{
bool orig_mcast_enabled = !(flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
u8 mcast_flags = BATADV_NO_FLAGS;
bool orig_initialized;
if (orig_mcast_enabled && tvlv_value &&
(tvlv_value_len >= sizeof(mcast_flags)))
mcast_flags = *(u8 *)tvlv_value;
spin_lock_bh(&orig->mcast_handler_lock);
orig_initialized = test_bit(BATADV_ORIG_CAPA_HAS_MCAST,
&orig->capa_initialized);
/* If mcast support is turned on decrease the disabled mcast node
* counter only if we had increased it for this node before. If this
* is a completely new orig_node no need to decrease the counter.
*/
if (orig_mcast_enabled &&
!test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities)) {
if (orig_initialized)
atomic_dec(&bat_priv->mcast.num_disabled);
set_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities);
/* If mcast support is being switched off or if this is an initial
* OGM without mcast support then increase the disabled mcast
* node counter.
*/
} else if (!orig_mcast_enabled &&
(test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities) ||
!orig_initialized)) {
atomic_inc(&bat_priv->mcast.num_disabled);
clear_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities);
}
set_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capa_initialized);
batadv_mcast_want_unsnoop_update(bat_priv, orig, mcast_flags);
batadv_mcast_want_ipv4_update(bat_priv, orig, mcast_flags);
batadv_mcast_want_ipv6_update(bat_priv, orig, mcast_flags);
orig->mcast_flags = mcast_flags;
spin_unlock_bh(&orig->mcast_handler_lock);
}
/**
* batadv_mcast_init - initialize the multicast optimizations structures
* @bat_priv: the bat priv with all the soft interface information
*/
void batadv_mcast_init(struct batadv_priv *bat_priv)
{
batadv_tvlv_handler_register(bat_priv, batadv_mcast_tvlv_ogm_handler_v1,
NULL, BATADV_TVLV_MCAST, 1,
BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
}
/**
* batadv_mcast_free - free the multicast optimizations structures
* @bat_priv: the bat priv with all the soft interface information
*/
void batadv_mcast_free(struct batadv_priv *bat_priv)
{
batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_MCAST, 1);
batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_MCAST, 1);
batadv_mcast_mla_tt_retract(bat_priv, NULL);
}
/**
* batadv_mcast_purge_orig - reset originator global mcast state modifications
* @orig: the originator which is going to get purged
*/
void batadv_mcast_purge_orig(struct batadv_orig_node *orig)
{
struct batadv_priv *bat_priv = orig->bat_priv;
spin_lock_bh(&orig->mcast_handler_lock);
if (!test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities) &&
test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capa_initialized))
atomic_dec(&bat_priv->mcast.num_disabled);
batadv_mcast_want_unsnoop_update(bat_priv, orig, BATADV_NO_FLAGS);
batadv_mcast_want_ipv4_update(bat_priv, orig, BATADV_NO_FLAGS);
batadv_mcast_want_ipv6_update(bat_priv, orig, BATADV_NO_FLAGS);
spin_unlock_bh(&orig->mcast_handler_lock);
}