summaryrefslogtreecommitdiffstats
path: root/net/batman-adv/multicast.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/batman-adv/multicast.c')
-rw-r--r--net/batman-adv/multicast.c181
1 files changed, 163 insertions, 18 deletions
diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c
index 4673328def29..eb30316e22fa 100644
--- a/net/batman-adv/multicast.c
+++ b/net/batman-adv/multicast.c
@@ -26,6 +26,7 @@
#include <linux/etherdevice.h>
#include <linux/fs.h>
#include <linux/icmpv6.h>
+#include <linux/if_bridge.h>
#include <linux/if_ether.h>
#include <linux/igmp.h>
#include <linux/in.h>
@@ -36,6 +37,7 @@
#include <linux/list.h>
#include <linux/lockdep.h>
#include <linux/netdevice.h>
+#include <linux/printk.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/skbuff.h>
@@ -45,18 +47,53 @@
#include <linux/string.h>
#include <linux/types.h>
#include <net/addrconf.h>
+#include <net/if_inet6.h>
+#include <net/ip.h>
#include <net/ipv6.h>
#include "packet.h"
#include "translation-table.h"
/**
+ * batadv_mcast_get_bridge - get the bridge on top of the softif if it exists
+ * @soft_iface: netdev struct of the mesh interface
+ *
+ * If the given soft interface has a bridge on top then the refcount
+ * of the according net device is increased.
+ *
+ * Return: NULL if no such bridge exists. Otherwise the net device of the
+ * bridge.
+ */
+static struct net_device *batadv_mcast_get_bridge(struct net_device *soft_iface)
+{
+ struct net_device *upper = soft_iface;
+
+ rcu_read_lock();
+ do {
+ upper = netdev_master_upper_dev_get_rcu(upper);
+ } while (upper && !(upper->priv_flags & IFF_EBRIDGE));
+
+ if (upper)
+ dev_hold(upper);
+ rcu_read_unlock();
+
+ return upper;
+}
+
+/**
* 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.
+ * Collects multicast addresses of multicast listeners residing
+ * on this kernel on the given soft interface, dev, in
+ * the given mcast_list. In general, multicast listeners provided by
+ * your multicast receiving applications run directly on this node.
+ *
+ * If there is a bridge interface on top of dev, collects from that one
+ * instead. Just like with IP addresses and routes, multicast listeners
+ * will(/should) register to the bridge interface instead of an
+ * enslaved bat0.
*
* Return: -ENOMEM on memory allocation error or the number of
* items added to the mcast_list otherwise.
@@ -64,12 +101,13 @@
static int batadv_mcast_mla_softif_get(struct net_device *dev,
struct hlist_head *mcast_list)
{
+ struct net_device *bridge = batadv_mcast_get_bridge(dev);
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) {
+ netif_addr_lock_bh(bridge ? bridge : dev);
+ netdev_for_each_mc_addr(mc_list_entry, bridge ? bridge : dev) {
new = kmalloc(sizeof(*new), GFP_ATOMIC);
if (!new) {
ret = -ENOMEM;
@@ -80,7 +118,10 @@ static int batadv_mcast_mla_softif_get(struct net_device *dev,
hlist_add_head(&new->list, mcast_list);
ret++;
}
- netif_addr_unlock_bh(dev);
+ netif_addr_unlock_bh(bridge ? bridge : dev);
+
+ if (bridge)
+ dev_put(bridge);
return ret;
}
@@ -106,6 +147,83 @@ static bool batadv_mcast_mla_is_duplicate(u8 *mcast_addr,
}
/**
+ * batadv_mcast_mla_br_addr_cpy - copy a bridge multicast address
+ * @dst: destination to write to - a multicast MAC address
+ * @src: source to read from - a multicast IP address
+ *
+ * Converts a given multicast IPv4/IPv6 address from a bridge
+ * to its matching multicast MAC address and copies it into the given
+ * destination buffer.
+ *
+ * Caller needs to make sure the destination buffer can hold
+ * at least ETH_ALEN bytes.
+ */
+static void batadv_mcast_mla_br_addr_cpy(char *dst, const struct br_ip *src)
+{
+ if (src->proto == htons(ETH_P_IP))
+ ip_eth_mc_map(src->u.ip4, dst);
+#if IS_ENABLED(CONFIG_IPV6)
+ else if (src->proto == htons(ETH_P_IPV6))
+ ipv6_eth_mc_map(&src->u.ip6, dst);
+#endif
+ else
+ eth_zero_addr(dst);
+}
+
+/**
+ * batadv_mcast_mla_bridge_get - get bridged-in multicast listeners
+ * @dev: a bridge slave whose bridge to collect multicast addresses from
+ * @mcast_list: a list to put found addresses into
+ *
+ * Collects multicast addresses of multicast listeners residing
+ * on foreign, non-mesh devices which we gave access to our mesh via
+ * a bridge on top of the given soft interface, dev, in the given
+ * mcast_list.
+ *
+ * Return: -ENOMEM on memory allocation error or the number of
+ * items added to the mcast_list otherwise.
+ */
+static int batadv_mcast_mla_bridge_get(struct net_device *dev,
+ struct hlist_head *mcast_list)
+{
+ struct list_head bridge_mcast_list = LIST_HEAD_INIT(bridge_mcast_list);
+ struct br_ip_list *br_ip_entry, *tmp;
+ struct batadv_hw_addr *new;
+ u8 mcast_addr[ETH_ALEN];
+ int ret;
+
+ /* we don't need to detect these devices/listeners, the IGMP/MLD
+ * snooping code of the Linux bridge already does that for us
+ */
+ ret = br_multicast_list_adjacent(dev, &bridge_mcast_list);
+ if (ret < 0)
+ goto out;
+
+ list_for_each_entry(br_ip_entry, &bridge_mcast_list, list) {
+ batadv_mcast_mla_br_addr_cpy(mcast_addr, &br_ip_entry->addr);
+ if (batadv_mcast_mla_is_duplicate(mcast_addr, mcast_list))
+ continue;
+
+ new = kmalloc(sizeof(*new), GFP_ATOMIC);
+ if (!new) {
+ ret = -ENOMEM;
+ break;
+ }
+
+ ether_addr_copy(new->addr, mcast_addr);
+ hlist_add_head(&new->list, mcast_list);
+ }
+
+out:
+ list_for_each_entry_safe(br_ip_entry, tmp, &bridge_mcast_list, list) {
+ list_del(&br_ip_entry->list);
+ kfree(br_ip_entry);
+ }
+
+ return ret;
+}
+
+/**
* 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
@@ -222,29 +340,51 @@ static bool batadv_mcast_has_bridge(struct batadv_priv *bat_priv)
* Updates the own multicast tvlv with our current multicast related settings,
* capabilities and inabilities.
*
- * Return: true if the tvlv container is registered afterwards. Otherwise
- * returns false.
+ * Return: false if we want all IPv4 && IPv6 multicast traffic and true
+ * otherwise.
*/
static bool batadv_mcast_mla_tvlv_update(struct batadv_priv *bat_priv)
{
struct batadv_tvlv_mcast_data mcast_data;
+ struct batadv_mcast_querier_state querier4 = {false, false};
+ struct batadv_mcast_querier_state querier6 = {false, false};
+ struct net_device *dev = bat_priv->soft_iface;
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)
+ bat_priv->mcast.bridged = batadv_mcast_has_bridge(bat_priv);
+ if (!bat_priv->mcast.bridged)
+ goto update;
+
+#if !IS_ENABLED(CONFIG_BRIDGE_IGMP_SNOOPING)
+ pr_warn_once("No bridge IGMP snooping compiled - multicast optimizations disabled\n");
+#endif
+
+ querier4.exists = br_multicast_has_querier_anywhere(dev, ETH_P_IP);
+ querier4.shadowing = br_multicast_has_querier_adjacent(dev, ETH_P_IP);
+
+ querier6.exists = br_multicast_has_querier_anywhere(dev, ETH_P_IPV6);
+ querier6.shadowing = br_multicast_has_querier_adjacent(dev, ETH_P_IPV6);
+
+ mcast_data.flags |= BATADV_MCAST_WANT_ALL_UNSNOOPABLES;
+
+ /* 1) If no querier exists at all, then multicast listeners on
+ * our local TT clients behind the bridge will keep silent.
+ * 2) If the selected querier is on one of our local TT clients,
+ * behind the bridge, then this querier might shadow multicast
+ * listeners on our local TT clients, behind this bridge.
+ *
+ * In both cases, we will signalize other batman nodes that
+ * we need all multicast traffic of the according protocol.
*/
- if (batadv_mcast_has_bridge(bat_priv)) {
- if (bat_priv->mcast.enabled) {
- batadv_tvlv_container_unregister(bat_priv,
- BATADV_TVLV_MCAST, 2);
- bat_priv->mcast.enabled = false;
- }
+ if (!querier4.exists || querier4.shadowing)
+ mcast_data.flags |= BATADV_MCAST_WANT_ALL_IPV4;
- return false;
- }
+ if (!querier6.exists || querier6.shadowing)
+ mcast_data.flags |= BATADV_MCAST_WANT_ALL_IPV6;
+update:
if (!bat_priv->mcast.enabled ||
mcast_data.flags != bat_priv->mcast.flags) {
batadv_tvlv_container_register(bat_priv, BATADV_TVLV_MCAST, 2,
@@ -253,7 +393,8 @@ static bool batadv_mcast_mla_tvlv_update(struct batadv_priv *bat_priv)
bat_priv->mcast.enabled = true;
}
- return true;
+ return !(mcast_data.flags &
+ (BATADV_MCAST_WANT_ALL_IPV4 + BATADV_MCAST_WANT_ALL_IPV6));
}
/**
@@ -276,6 +417,10 @@ void batadv_mcast_mla_update(struct batadv_priv *bat_priv)
if (ret < 0)
goto out;
+ ret = batadv_mcast_mla_bridge_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);