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/*
* Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
* Copyright (c) 2012 Pablo Neira Ayuso <pablo@netfilter.org>
*
* 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.
*/
#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_ipv4.h>
#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables_ipv4.h>
#include <net/route.h>
#include <net/ip.h>
static unsigned int nf_route_table_hook(const struct nf_hook_ops *ops,
struct sk_buff *skb,
const struct nf_hook_state *state)
{
unsigned int ret;
struct nft_pktinfo pkt;
u32 mark;
__be32 saddr, daddr;
u_int8_t tos;
const struct iphdr *iph;
/* root is playing with raw sockets. */
if (skb->len < sizeof(struct iphdr) ||
ip_hdrlen(skb) < sizeof(struct iphdr))
return NF_ACCEPT;
nft_set_pktinfo_ipv4(&pkt, skb, state);
mark = skb->mark;
iph = ip_hdr(skb);
saddr = iph->saddr;
daddr = iph->daddr;
tos = iph->tos;
ret = nft_do_chain(&pkt, ops);
if (ret != NF_DROP && ret != NF_QUEUE) {
iph = ip_hdr(skb);
if (iph->saddr != saddr ||
iph->daddr != daddr ||
skb->mark != mark ||
iph->tos != tos)
if (ip_route_me_harder(skb, RTN_UNSPEC))
ret = NF_DROP;
}
return ret;
}
static const struct nf_chain_type nft_chain_route_ipv4 = {
.name = "route",
.type = NFT_CHAIN_T_ROUTE,
.family = NFPROTO_IPV4,
.owner = THIS_MODULE,
.hook_mask = (1 << NF_INET_LOCAL_OUT),
.hooks = {
[NF_INET_LOCAL_OUT] = nf_route_table_hook,
},
};
static int __init nft_chain_route_init(void)
{
return nft_register_chain_type(&nft_chain_route_ipv4);
}
static void __exit nft_chain_route_exit(void)
{
nft_unregister_chain_type(&nft_chain_route_ipv4);
}
module_init(nft_chain_route_init);
module_exit(nft_chain_route_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_ALIAS_NFT_CHAIN(AF_INET, "route");
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