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/*
* Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Development of this code funded by Astaro AG (http://www.astaro.com/)
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/skbuff.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv6.h>
#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables.h>
#include <net/route.h>
static unsigned int nf_route_table_hook(const struct nf_hook_ops *ops,
struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
unsigned int ret;
struct in6_addr saddr, daddr;
u_int8_t hop_limit;
u32 mark, flowlabel;
/* save source/dest address, mark, hoplimit, flowlabel, priority */
memcpy(&saddr, &ipv6_hdr(skb)->saddr, sizeof(saddr));
memcpy(&daddr, &ipv6_hdr(skb)->daddr, sizeof(daddr));
mark = skb->mark;
hop_limit = ipv6_hdr(skb)->hop_limit;
/* flowlabel and prio (includes version, which shouldn't change either */
flowlabel = *((u32 *)ipv6_hdr(skb));
ret = nft_do_chain(ops, skb, in, out, okfn);
if (ret != NF_DROP && ret != NF_QUEUE &&
(memcmp(&ipv6_hdr(skb)->saddr, &saddr, sizeof(saddr)) ||
memcmp(&ipv6_hdr(skb)->daddr, &daddr, sizeof(daddr)) ||
skb->mark != mark ||
ipv6_hdr(skb)->hop_limit != hop_limit ||
flowlabel != *((u_int32_t *)ipv6_hdr(skb))))
return ip6_route_me_harder(skb) == 0 ? ret : NF_DROP;
return ret;
}
static struct nft_base_chain nf_chain_route_output __read_mostly = {
.chain = {
.name = "OUTPUT",
.rules = LIST_HEAD_INIT(nf_chain_route_output.chain.rules),
.flags = NFT_BASE_CHAIN | NFT_CHAIN_BUILTIN,
},
.ops = {
.hook = nf_route_table_hook,
.owner = THIS_MODULE,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_LOCAL_OUT,
.priority = NF_IP6_PRI_MANGLE,
.priv = &nf_chain_route_output.chain,
},
};
static struct nft_table nf_table_route_ipv6 __read_mostly = {
.name = "route",
.chains = LIST_HEAD_INIT(nf_table_route_ipv6.chains),
};
static int __init nf_table_route_init(void)
{
list_add_tail(&nf_chain_route_output.chain.list,
&nf_table_route_ipv6.chains);
return nft_register_table(&nf_table_route_ipv6, NFPROTO_IPV6);
}
static void __exit nf_table_route_exit(void)
{
nft_unregister_table(&nf_table_route_ipv6, NFPROTO_IPV6);
}
module_init(nf_table_route_init);
module_exit(nf_table_route_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_ALIAS_NFT_TABLE(AF_INET6, "route");
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