148 lines
3.4 KiB
C
148 lines
3.4 KiB
C
#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>
|
|
#include <net/ip6_checksum.h>
|
|
#include <net/netfilter/nf_queue.h>
|
|
|
|
int ip6_route_me_harder(struct sk_buff *skb)
|
|
{
|
|
struct ipv6hdr *iph = ipv6_hdr(skb);
|
|
struct dst_entry *dst;
|
|
struct flowi fl = {
|
|
.oif = skb->sk ? skb->sk->sk_bound_dev_if : 0,
|
|
.mark = skb->mark,
|
|
.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(ip6_dst_idev(dst), 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 nf_ip6_saveroute(const struct sk_buff *skb,
|
|
struct nf_queue_entry *entry)
|
|
{
|
|
struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry);
|
|
|
|
if (entry->hook == NF_INET_LOCAL_OUT) {
|
|
struct ipv6hdr *iph = ipv6_hdr(skb);
|
|
|
|
rt_info->daddr = iph->daddr;
|
|
rt_info->saddr = iph->saddr;
|
|
}
|
|
}
|
|
|
|
static int nf_ip6_reroute(struct sk_buff *skb,
|
|
const struct nf_queue_entry *entry)
|
|
{
|
|
struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry);
|
|
|
|
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))
|
|
return ip6_route_me_harder(skb);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int nf_ip6_route(struct dst_entry **dst, struct flowi *fl)
|
|
{
|
|
*dst = ip6_route_output(NULL, fl);
|
|
return (*dst)->error;
|
|
}
|
|
|
|
__sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook,
|
|
unsigned int dataoff, u_int8_t protocol)
|
|
{
|
|
struct ipv6hdr *ip6h = ipv6_hdr(skb);
|
|
__sum16 csum = 0;
|
|
|
|
switch (skb->ip_summed) {
|
|
case CHECKSUM_COMPLETE:
|
|
if (hook != NF_INET_PRE_ROUTING && hook != NF_INET_LOCAL_IN)
|
|
break;
|
|
if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
|
|
skb->len - dataoff, protocol,
|
|
csum_sub(skb->csum,
|
|
skb_checksum(skb, 0,
|
|
dataoff, 0)))) {
|
|
skb->ip_summed = CHECKSUM_UNNECESSARY;
|
|
break;
|
|
}
|
|
/* fall through */
|
|
case CHECKSUM_NONE:
|
|
skb->csum = ~csum_unfold(
|
|
csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
|
|
skb->len - dataoff,
|
|
protocol,
|
|
csum_sub(0,
|
|
skb_checksum(skb, 0,
|
|
dataoff, 0))));
|
|
csum = __skb_checksum_complete(skb);
|
|
}
|
|
return csum;
|
|
}
|
|
|
|
EXPORT_SYMBOL(nf_ip6_checksum);
|
|
|
|
static struct nf_afinfo nf_ip6_afinfo = {
|
|
.family = AF_INET6,
|
|
.checksum = nf_ip6_checksum,
|
|
.route = nf_ip6_route,
|
|
.saveroute = nf_ip6_saveroute,
|
|
.reroute = nf_ip6_reroute,
|
|
.route_key_size = sizeof(struct ip6_rt_info),
|
|
};
|
|
|
|
int __init ipv6_netfilter_init(void)
|
|
{
|
|
return nf_register_afinfo(&nf_ip6_afinfo);
|
|
}
|
|
|
|
/* This can be called from inet6_init() on errors, so it cannot
|
|
* be marked __exit. -DaveM
|
|
*/
|
|
void ipv6_netfilter_fini(void)
|
|
{
|
|
nf_unregister_afinfo(&nf_ip6_afinfo);
|
|
}
|