130 строки
3.2 KiB
C
130 строки
3.2 KiB
C
/*
|
|
* IPv6 specific functions of netfilter core
|
|
*
|
|
* Rusty Russell (C) 2000 -- This code is GPL.
|
|
* Patrick McHardy (C) 2006-2012
|
|
*/
|
|
#include <linux/kernel.h>
|
|
#include <linux/init.h>
|
|
#include <linux/ipv6.h>
|
|
#include <linux/netfilter.h>
|
|
#include <linux/netfilter_ipv6.h>
|
|
#include <linux/export.h>
|
|
#include <net/addrconf.h>
|
|
#include <net/dst.h>
|
|
#include <net/ipv6.h>
|
|
#include <net/ip6_route.h>
|
|
#include <net/xfrm.h>
|
|
#include <net/netfilter/nf_queue.h>
|
|
|
|
int ip6_route_me_harder(struct net *net, struct sk_buff *skb)
|
|
{
|
|
const struct ipv6hdr *iph = ipv6_hdr(skb);
|
|
struct sock *sk = sk_to_full_sk(skb->sk);
|
|
unsigned int hh_len;
|
|
struct dst_entry *dst;
|
|
struct flowi6 fl6 = {
|
|
.flowi6_oif = sk && sk->sk_bound_dev_if ? sk->sk_bound_dev_if :
|
|
rt6_need_strict(&iph->daddr) ? skb_dst(skb)->dev->ifindex : 0,
|
|
.flowi6_mark = skb->mark,
|
|
.flowi6_uid = sock_net_uid(net, sk),
|
|
.daddr = iph->daddr,
|
|
.saddr = iph->saddr,
|
|
};
|
|
int err;
|
|
|
|
dst = ip6_route_output(net, sk, &fl6);
|
|
err = dst->error;
|
|
if (err) {
|
|
IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
|
|
net_dbg_ratelimited("ip6_route_me_harder: No more route\n");
|
|
dst_release(dst);
|
|
return err;
|
|
}
|
|
|
|
/* Drop old route. */
|
|
skb_dst_drop(skb);
|
|
|
|
skb_dst_set(skb, dst);
|
|
|
|
#ifdef CONFIG_XFRM
|
|
if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) &&
|
|
xfrm_decode_session(skb, flowi6_to_flowi(&fl6), AF_INET6) == 0) {
|
|
skb_dst_set(skb, NULL);
|
|
dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), sk, 0);
|
|
if (IS_ERR(dst))
|
|
return PTR_ERR(dst);
|
|
skb_dst_set(skb, dst);
|
|
}
|
|
#endif
|
|
|
|
/* Change in oif may mean change in hh_len. */
|
|
hh_len = skb_dst(skb)->dev->hard_header_len;
|
|
if (skb_headroom(skb) < hh_len &&
|
|
pskb_expand_head(skb, HH_DATA_ALIGN(hh_len - skb_headroom(skb)),
|
|
0, GFP_ATOMIC))
|
|
return -ENOMEM;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(ip6_route_me_harder);
|
|
|
|
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->state.hook == NF_INET_LOCAL_OUT) {
|
|
const struct ipv6hdr *iph = ipv6_hdr(skb);
|
|
if (!ipv6_addr_equal(&iph->daddr, &rt_info->daddr) ||
|
|
!ipv6_addr_equal(&iph->saddr, &rt_info->saddr) ||
|
|
skb->mark != rt_info->mark)
|
|
return ip6_route_me_harder(entry->state.net, skb);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int nf_ip6_route(struct net *net, struct dst_entry **dst,
|
|
struct flowi *fl, bool strict)
|
|
{
|
|
static const struct ipv6_pinfo fake_pinfo;
|
|
static const struct inet_sock fake_sk = {
|
|
/* makes ip6_route_output set RT6_LOOKUP_F_IFACE: */
|
|
.sk.sk_bound_dev_if = 1,
|
|
.pinet6 = (struct ipv6_pinfo *) &fake_pinfo,
|
|
};
|
|
const void *sk = strict ? &fake_sk : NULL;
|
|
struct dst_entry *result;
|
|
int err;
|
|
|
|
result = ip6_route_output(net, sk, &fl->u.ip6);
|
|
err = result->error;
|
|
if (err)
|
|
dst_release(result);
|
|
else
|
|
*dst = result;
|
|
return err;
|
|
}
|
|
|
|
static const struct nf_ipv6_ops ipv6ops = {
|
|
.chk_addr = ipv6_chk_addr,
|
|
.route_input = ip6_route_input,
|
|
.fragment = ip6_fragment,
|
|
.route = nf_ip6_route,
|
|
.reroute = nf_ip6_reroute,
|
|
};
|
|
|
|
int __init ipv6_netfilter_init(void)
|
|
{
|
|
RCU_INIT_POINTER(nf_ipv6_ops, &ipv6ops);
|
|
return 0;
|
|
}
|
|
|
|
/* This can be called from inet6_init() on errors, so it cannot
|
|
* be marked __exit. -DaveM
|
|
*/
|
|
void ipv6_netfilter_fini(void)
|
|
{
|
|
RCU_INIT_POINTER(nf_ipv6_ops, NULL);
|
|
}
|