[NETFILTER] ctnetlink: add marking support from userspace

This patch adds support for conntrack marking from user space.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NHarald Welte <laforge@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/netfilter/ip_conntrack_netlink.c

@@ -979,6 +979,11 @@ ctnetlink_change_conntrack(struct ip_conntrack *ct, struct nfattr *cda[])
 			return err;
 	}
 
+#if defined(CONFIG_IP_NF_CONNTRACK_MARK)
+	if (cda[CTA_MARK-1])
+		ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
+#endif
+
 	DEBUGP("all done\n");
 	return 0;
 }
@@ -1022,6 +1027,11 @@ ctnetlink_create_conntrack(struct nfattr *cda[],
 	if (ct->helper)
 		ip_conntrack_helper_put(ct->helper);
 
+#if defined(CONFIG_IP_NF_CONNTRACK_MARK)
+	if (cda[CTA_MARK-1])
+		ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
+#endif
+
 	DEBUGP("conntrack with id %u inserted\n", ct->id);
 	return 0;