kernel-fxtec-pro1x/net/ipv4/xfrm4_output.c
Herbert Xu 1bfcb10f67 [IPSEC]: Add missing BEET checks
Currently BEET mode does not reinject the packet back into the stack
like tunnel mode does.  Since BEET should behave just like tunnel mode
this is incorrect.

This patch fixes this by introducing a flags field to xfrm_mode that
tells the IPsec code whether it should terminate and reinject the packet
back into the stack.

It then sets the flag for BEET and tunnel mode.

I've also added a number of missing BEET checks elsewhere where we check
whether a given mode is a tunnel or not.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-17 21:31:50 -07:00

145 lines
2.9 KiB
C

/*
* xfrm4_output.c - Common IPsec encapsulation code for IPv4.
* Copyright (c) 2004 Herbert Xu <herbert@gondor.apana.org.au>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/compiler.h>
#include <linux/if_ether.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/netfilter_ipv4.h>
#include <net/ip.h>
#include <net/xfrm.h>
#include <net/icmp.h>
static int xfrm4_tunnel_check_size(struct sk_buff *skb)
{
int mtu, ret = 0;
struct dst_entry *dst;
if (IPCB(skb)->flags & IPSKB_XFRM_TUNNEL_SIZE)
goto out;
IPCB(skb)->flags |= IPSKB_XFRM_TUNNEL_SIZE;
if (!(ip_hdr(skb)->frag_off & htons(IP_DF)) || skb->local_df)
goto out;
dst = skb->dst;
mtu = dst_mtu(dst);
if (skb->len > mtu) {
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
ret = -EMSGSIZE;
}
out:
return ret;
}
static inline int xfrm4_output_one(struct sk_buff *skb)
{
struct dst_entry *dst = skb->dst;
struct xfrm_state *x = dst->xfrm;
struct iphdr *iph;
int err;
if (x->mode->flags & XFRM_MODE_FLAG_TUNNEL) {
err = xfrm4_tunnel_check_size(skb);
if (err)
goto error_nolock;
}
err = xfrm_output(skb);
if (err)
goto error_nolock;
iph = ip_hdr(skb);
iph->tot_len = htons(skb->len);
ip_send_check(iph);
IPCB(skb)->flags |= IPSKB_XFRM_TRANSFORMED;
err = 0;
out_exit:
return err;
error_nolock:
kfree_skb(skb);
goto out_exit;
}
static int xfrm4_output_finish2(struct sk_buff *skb)
{
int err;
while (likely((err = xfrm4_output_one(skb)) == 0)) {
nf_reset(skb);
err = nf_hook(PF_INET, NF_IP_LOCAL_OUT, skb, NULL,
skb->dst->dev, dst_output);
if (unlikely(err != 1))
break;
if (!skb->dst->xfrm)
return dst_output(skb);
err = nf_hook(PF_INET, NF_IP_POST_ROUTING, skb, NULL,
skb->dst->dev, xfrm4_output_finish2);
if (unlikely(err != 1))
break;
}
return err;
}
static int xfrm4_output_finish(struct sk_buff *skb)
{
struct sk_buff *segs;
#ifdef CONFIG_NETFILTER
if (!skb->dst->xfrm) {
IPCB(skb)->flags |= IPSKB_REROUTED;
return dst_output(skb);
}
#endif
if (!skb_is_gso(skb))
return xfrm4_output_finish2(skb);
skb->protocol = htons(ETH_P_IP);
segs = skb_gso_segment(skb, 0);
kfree_skb(skb);
if (unlikely(IS_ERR(segs)))
return PTR_ERR(segs);
do {
struct sk_buff *nskb = segs->next;
int err;
segs->next = NULL;
err = xfrm4_output_finish2(segs);
if (unlikely(err)) {
while ((segs = nskb)) {
nskb = segs->next;
segs->next = NULL;
kfree_skb(segs);
}
return err;
}
segs = nskb;
} while (segs);
return 0;
}
int xfrm4_output(struct sk_buff *skb)
{
return NF_HOOK_COND(PF_INET, NF_IP_POST_ROUTING, skb, NULL, skb->dst->dev,
xfrm4_output_finish,
!(IPCB(skb)->flags & IPSKB_REROUTED));
}