[NETFILTER]: Redo policy lookups after NAT when neccessary

When NAT changes the key used for the xfrm lookup it needs to be done
again. If a new policy is returned in POST_ROUTING the packet needs
to be passed to xfrm4_output_one manually after all hooks were called
because POST_ROUTING is called with fixed okfn (ip_finish_output).

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Patrick McHardy 2006-01-06 23:05:36 -08:00 committed by David S. Miller
parent 4e8e9de7c2
commit 5c901daaea
4 changed files with 32 additions and 3 deletions

View File

@ -866,6 +866,7 @@ extern int xfrm_state_mtu(struct xfrm_state *x, int mtu);
extern int xfrm_init_state(struct xfrm_state *x);
extern int xfrm4_rcv(struct sk_buff *skb);
extern int xfrm4_output(struct sk_buff *skb);
extern int xfrm4_output_finish(struct sk_buff *skb);
extern int xfrm4_tunnel_register(struct xfrm_tunnel *handler);
extern int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler);
extern int xfrm6_rcv_spi(struct sk_buff **pskb, u32 spi);

View File

@ -202,6 +202,11 @@ static inline int ip_finish_output2(struct sk_buff *skb)
static inline int ip_finish_output(struct sk_buff *skb)
{
#if defined(CONFIG_NETFILTER) && defined(CONFIG_XFRM)
/* Policy lookup after SNAT yielded a new policy */
if (skb->dst->xfrm != NULL)
return xfrm4_output_finish(skb);
#endif
if (skb->len > dst_mtu(skb->dst) &&
!(skb_shinfo(skb)->ufo_size || skb_shinfo(skb)->tso_size))
return ip_fragment(skb, ip_finish_output2);

View File

@ -187,12 +187,30 @@ ip_nat_out(unsigned int hooknum,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
struct ip_conntrack *ct;
enum ip_conntrack_info ctinfo;
unsigned int ret;
/* root is playing with raw sockets. */
if ((*pskb)->len < sizeof(struct iphdr)
|| (*pskb)->nh.iph->ihl * 4 < sizeof(struct iphdr))
return NF_ACCEPT;
return ip_nat_fn(hooknum, pskb, in, out, okfn);
ret = ip_nat_fn(hooknum, pskb, in, out, okfn);
if (ret != NF_DROP && ret != NF_STOLEN
&& (ct = ip_conntrack_get(*pskb, &ctinfo)) != NULL) {
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
if (ct->tuplehash[dir].tuple.src.ip !=
ct->tuplehash[!dir].tuple.dst.ip
#ifdef CONFIG_XFRM
|| ct->tuplehash[dir].tuple.src.u.all !=
ct->tuplehash[!dir].tuple.dst.u.all
#endif
)
return ip_route_me_harder(pskb) == 0 ? ret : NF_DROP;
}
return ret;
}
static unsigned int
@ -217,7 +235,12 @@ ip_nat_local_fn(unsigned int hooknum,
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
if (ct->tuplehash[dir].tuple.dst.ip !=
ct->tuplehash[!dir].tuple.src.ip)
ct->tuplehash[!dir].tuple.src.ip
#ifdef CONFIG_XFRM
|| ct->tuplehash[dir].tuple.dst.u.all !=
ct->tuplehash[dir].tuple.src.u.all
#endif
)
return ip_route_me_harder(pskb) == 0 ? ret : NF_DROP;
}
return ret;

View File

@ -152,7 +152,7 @@ static int xfrm4_output_one(struct sk_buff *skb)
goto out_exit;
}
static int xfrm4_output_finish(struct sk_buff *skb)
int xfrm4_output_finish(struct sk_buff *skb)
{
int err;