netfilter: nfmark IPV6 routing in OUTPUT, mangle, NFQUEUE

This patch let nfmark to be evaluated for routing decision for OUTPUT
packet, in mangle table, when process paquet in NFQUEUE. This patch is
an IPv6 port of Laurent Licour IPv4 one.
Signed-off-by: Eric Leblond <eric@inl.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>

net/ipv6/netfilter.c

@@ -56,6 +56,7 @@ EXPORT_SYMBOL(ip6_route_me_harder);
 struct ip6_rt_info {
 	struct in6_addr daddr;
 	struct in6_addr saddr;
+	u_int32_t mark;
 };
 
 static void nf_ip6_saveroute(const struct sk_buff *skb,
@@ -68,6 +69,7 @@ static void nf_ip6_saveroute(const struct sk_buff *skb,
 
 		rt_info->daddr = iph->daddr;
 		rt_info->saddr = iph->saddr;
+		rt_info->mark = skb->mark;
 	}
 }
 
@@ -79,7 +81,8 @@ static int nf_ip6_reroute(struct sk_buff *skb,
 	if (entry->hook == NF_INET_LOCAL_OUT) {
 		struct ipv6hdr *iph = ipv6_hdr(skb);
 		if (!ipv6_addr_equal(&iph->daddr, &rt_info->daddr) ||
-		    !ipv6_addr_equal(&iph->saddr, &rt_info->saddr))
+		    !ipv6_addr_equal(&iph->saddr, &rt_info->saddr) ||
+		    skb->mark != rt_info->mark)
 			return ip6_route_me_harder(skb);
 	}
 	return 0;