batman-adv: mcast: collect softif listeners from IP lists instead
Instead of collecting multicast MAC addresses from the netdev hw mc
list collect a node's multicast listeners from the IP lists and convert
those to MAC addresses.
This allows to exclude addresses of specific scope later. On a
multicast MAC address the IP destination scope is not visible anymore.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c
index af0e2ce..ca9e2e67 100644
--- a/net/batman-adv/multicast.c
+++ b/net/batman-adv/multicast.c
@@ -20,6 +20,7 @@
#include <linux/igmp.h>
#include <linux/in.h>
#include <linux/in6.h>
+#include <linux/inetdevice.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/jiffies.h>
@@ -172,34 +173,157 @@ static struct net_device *batadv_mcast_get_bridge(struct net_device *soft_iface)
}
/**
- * batadv_mcast_addr_is_ipv4() - check if multicast MAC is IPv4
- * @addr: the MAC address to check
+ * 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
*
- * Return: True, if MAC address is one reserved for IPv4 multicast, false
- * otherwise.
+ * Return: true if the given address is already in the given list.
+ * Otherwise returns false.
*/
-static bool batadv_mcast_addr_is_ipv4(const u8 *addr)
+static bool batadv_mcast_mla_is_duplicate(u8 *mcast_addr,
+ struct hlist_head *mcast_list)
{
- static const u8 prefix[] = {0x01, 0x00, 0x5E};
+ struct batadv_hw_addr *mcast_entry;
- return memcmp(prefix, addr, sizeof(prefix)) == 0;
+ hlist_for_each_entry(mcast_entry, mcast_list, list)
+ if (batadv_compare_eth(mcast_entry->addr, mcast_addr))
+ return true;
+
+ return false;
}
/**
- * batadv_mcast_addr_is_ipv6() - check if multicast MAC is IPv6
- * @addr: the MAC address to check
+ * batadv_mcast_mla_softif_get_ipv4() - get softif IPv4 multicast listeners
+ * @dev: the device to collect multicast addresses from
+ * @mcast_list: a list to put found addresses into
+ * @flags: flags indicating the new multicast state
*
- * Return: True, if MAC address is one reserved for IPv6 multicast, false
- * otherwise.
+ * Collects multicast addresses of IPv4 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.
+ *
+ * Return: -ENOMEM on memory allocation error or the number of
+ * items added to the mcast_list otherwise.
*/
-static bool batadv_mcast_addr_is_ipv6(const u8 *addr)
+static int
+batadv_mcast_mla_softif_get_ipv4(struct net_device *dev,
+ struct hlist_head *mcast_list,
+ struct batadv_mcast_mla_flags *flags)
{
- static const u8 prefix[] = {0x33, 0x33};
+ struct batadv_hw_addr *new;
+ struct in_device *in_dev;
+ u8 mcast_addr[ETH_ALEN];
+ struct ip_mc_list *pmc;
+ int ret = 0;
- return memcmp(prefix, addr, sizeof(prefix)) == 0;
+ if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_IPV4)
+ return 0;
+
+ rcu_read_lock();
+
+ in_dev = __in_dev_get_rcu(dev);
+ if (!in_dev) {
+ rcu_read_unlock();
+ return 0;
+ }
+
+ for (pmc = rcu_dereference(in_dev->mc_list); pmc;
+ pmc = rcu_dereference(pmc->next_rcu)) {
+ ip_eth_mc_map(pmc->multiaddr, mcast_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);
+ ret++;
+ }
+ rcu_read_unlock();
+
+ return ret;
}
/**
+ * batadv_mcast_mla_softif_get_ipv6() - get softif IPv6 multicast listeners
+ * @dev: the device to collect multicast addresses from
+ * @mcast_list: a list to put found addresses into
+ * @flags: flags indicating the new multicast state
+ *
+ * Collects multicast addresses of IPv6 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.
+ *
+ * Return: -ENOMEM on memory allocation error or the number of
+ * items added to the mcast_list otherwise.
+ */
+#if IS_ENABLED(CONFIG_IPV6)
+static int
+batadv_mcast_mla_softif_get_ipv6(struct net_device *dev,
+ struct hlist_head *mcast_list,
+ struct batadv_mcast_mla_flags *flags)
+{
+ struct batadv_hw_addr *new;
+ struct inet6_dev *in6_dev;
+ u8 mcast_addr[ETH_ALEN];
+ struct ifmcaddr6 *pmc6;
+ int ret = 0;
+
+ if (flags->tvlv_flags & BATADV_MCAST_WANT_ALL_IPV6)
+ return 0;
+
+ rcu_read_lock();
+
+ in6_dev = __in6_dev_get(dev);
+ if (!in6_dev) {
+ rcu_read_unlock();
+ return 0;
+ }
+
+ read_lock_bh(&in6_dev->lock);
+ for (pmc6 = in6_dev->mc_list; pmc6; pmc6 = pmc6->next) {
+ if (IPV6_ADDR_MC_SCOPE(&pmc6->mca_addr) <
+ IPV6_ADDR_SCOPE_LINKLOCAL)
+ continue;
+
+ ipv6_eth_mc_map(&pmc6->mca_addr, mcast_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);
+ ret++;
+ }
+ read_unlock_bh(&in6_dev->lock);
+ rcu_read_unlock();
+
+ return ret;
+}
+#else
+static inline int
+batadv_mcast_mla_softif_get_ipv6(struct net_device *dev,
+ struct hlist_head *mcast_list,
+ struct batadv_mcast_mla_flags *flags)
+{
+ return 0;
+}
+#endif
+
+/**
* 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
@@ -223,57 +347,27 @@ batadv_mcast_mla_softif_get(struct net_device *dev,
struct hlist_head *mcast_list,
struct batadv_mcast_mla_flags *flags)
{
- bool all_ipv4 = flags->tvlv_flags & BATADV_MCAST_WANT_ALL_IPV4;
- bool all_ipv6 = flags->tvlv_flags & BATADV_MCAST_WANT_ALL_IPV6;
struct net_device *bridge = batadv_mcast_get_bridge(dev);
- struct netdev_hw_addr *mc_list_entry;
- struct batadv_hw_addr *new;
- int ret = 0;
+ int ret4, ret6 = 0;
- netif_addr_lock_bh(bridge ? bridge : dev);
- netdev_for_each_mc_addr(mc_list_entry, bridge ? bridge : dev) {
- if (all_ipv4 && batadv_mcast_addr_is_ipv4(mc_list_entry->addr))
- continue;
+ if (bridge)
+ dev = bridge;
- if (all_ipv6 && batadv_mcast_addr_is_ipv6(mc_list_entry->addr))
- continue;
+ ret4 = batadv_mcast_mla_softif_get_ipv4(dev, mcast_list, flags);
+ if (ret4 < 0)
+ goto out;
- 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++;
+ ret6 = batadv_mcast_mla_softif_get_ipv6(dev, mcast_list, flags);
+ if (ret6 < 0) {
+ ret4 = 0;
+ goto out;
}
- netif_addr_unlock_bh(bridge ? bridge : dev);
+out:
if (bridge)
dev_put(bridge);
- 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
- *
- * Return: 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;
+ return ret4 + ret6;
}
/**