netfilter: xtables: fix IPv6 dependency in the cluster match
This patch fixes a dependency with IPv6:
ERROR: "__ipv6_addr_type" [net/netfilter/xt_cluster.ko] undefined!
This patch adds a function that checks if the higher bits of the
address is 0xFF to identify a multicast address, instead of adding a
dependency due to __ipv6_addr_type(). I came up with this idea after
Patrick McHardy pointed possible problems with runtime module
dependencies.
Reported-by: Steven Noonan <steven@uplinklabs.net>
Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Reported-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/netfilter/xt_cluster.c b/net/netfilter/xt_cluster.c
index ad5bd89..6c48476 100644
--- a/net/netfilter/xt_cluster.c
+++ b/net/netfilter/xt_cluster.c
@@ -58,6 +58,13 @@
}
static inline bool
+xt_cluster_ipv6_is_multicast(const struct in6_addr *addr)
+{
+ __be32 st = addr->s6_addr32[0];
+ return ((st & htonl(0xFF000000)) == htonl(0xFF000000));
+}
+
+static inline bool
xt_cluster_is_multicast_addr(const struct sk_buff *skb, u_int8_t family)
{
bool is_multicast = false;
@@ -67,8 +74,8 @@
is_multicast = ipv4_is_multicast(ip_hdr(skb)->daddr);
break;
case NFPROTO_IPV6:
- is_multicast = ipv6_addr_type(&ipv6_hdr(skb)->daddr) &
- IPV6_ADDR_MULTICAST;
+ is_multicast =
+ xt_cluster_ipv6_is_multicast(&ipv6_hdr(skb)->daddr);
break;
default:
WARN_ON(1);