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#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/ipv6.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv6.h>
#include <net/dst.h>
#include <net/ipv6.h>
#include <net/ip6_route.h>
#include <net/xfrm.h>
int ip6_route_me_harder(struct sk_buff *skb)
{
struct ipv6hdr *iph = skb->nh.ipv6h;
struct dst_entry *dst;
struct flowi fl = {
.oif = skb->sk ? skb->sk->sk_bound_dev_if : 0,
.nl_u =
{ .ip6_u =
{ .daddr = iph->daddr,
.saddr = iph->saddr, } },
};
dst = ip6_route_output(skb->sk, &fl);
#ifdef CONFIG_XFRM
if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) &&
xfrm_decode_session(skb, &fl, AF_INET6) == 0)
if (xfrm_lookup(&skb->dst, &fl, skb->sk, 0))
return -1;
#endif
if (dst->error) {
IP6_INC_STATS(IPSTATS_MIB_OUTNOROUTES);
LIMIT_NETDEBUG(KERN_DEBUG "ip6_route_me_harder: No more route.\n");
dst_release(dst);
return -EINVAL;
}
/* Drop old route. */
dst_release(skb->dst);
skb->dst = dst;
return 0;
}
EXPORT_SYMBOL(ip6_route_me_harder);
/*
* Extra routing may needed on local out, as the QUEUE target never
* returns control to the table.
*/
struct ip6_rt_info {
struct in6_addr daddr;
struct in6_addr saddr;
};
static void save(const struct sk_buff *skb, struct nf_info *info)
{
struct ip6_rt_info *rt_info = nf_info_reroute(info);
if (info->hook == NF_IP6_LOCAL_OUT) {
struct ipv6hdr *iph = skb->nh.ipv6h;
rt_info->daddr = iph->daddr;
rt_info->saddr = iph->saddr;
}
}
static int reroute(struct sk_buff **pskb, const struct nf_info *info)
{
struct ip6_rt_info *rt_info = nf_info_reroute(info);
if (info->hook == NF_IP6_LOCAL_OUT) {
struct ipv6hdr *iph = (*pskb)->nh.ipv6h;
if (!ipv6_addr_equal(&iph->daddr, &rt_info->daddr) ||
!ipv6_addr_equal(&iph->saddr, &rt_info->saddr))
return ip6_route_me_harder(*pskb);
}
return 0;
}
static struct nf_queue_rerouter ip6_reroute = {
.rer_size = sizeof(struct ip6_rt_info),
.save = &save,
.reroute = &reroute,
};
int __init ipv6_netfilter_init(void)
{
return nf_register_queue_rerouter(PF_INET6, &ip6_reroute);
}
void __exit ipv6_netfilter_fini(void)
{
nf_unregister_queue_rerouter(PF_INET6);
}
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