995908dc5b
[ Upstream commit 0c922a4850eba2e668f73a3f1153196e09abb251 ] IPSKB_XFRM_TRANSFORMED and IP6SKB_XFRM_TRANSFORMED are skb flags set by xfrm code to tell other skb handlers that the packet has been passed through the xfrm output functions. Simplify the code and just always set them rather than conditionally based on netfilter enabled thus making the flag available for other users. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
114 lines
2.7 KiB
C
114 lines
2.7 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/if_ether.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/netfilter_ipv4.h>
|
|
#include <net/dst.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;
|
|
|
|
if (IPCB(skb)->flags & IPSKB_XFRM_TUNNEL_SIZE)
|
|
goto out;
|
|
|
|
if (!(ip_hdr(skb)->frag_off & htons(IP_DF)) || skb->ignore_df)
|
|
goto out;
|
|
|
|
mtu = dst_mtu(skb_dst(skb));
|
|
if ((!skb_is_gso(skb) && skb->len > mtu) ||
|
|
(skb_is_gso(skb) &&
|
|
!skb_gso_validate_network_len(skb, ip_skb_dst_mtu(skb->sk, skb)))) {
|
|
skb->protocol = htons(ETH_P_IP);
|
|
|
|
if (skb->sk)
|
|
xfrm_local_error(skb, mtu);
|
|
else
|
|
icmp_send(skb, ICMP_DEST_UNREACH,
|
|
ICMP_FRAG_NEEDED, htonl(mtu));
|
|
ret = -EMSGSIZE;
|
|
}
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
int xfrm4_extract_output(struct xfrm_state *x, struct sk_buff *skb)
|
|
{
|
|
int err;
|
|
|
|
err = xfrm4_tunnel_check_size(skb);
|
|
if (err)
|
|
return err;
|
|
|
|
XFRM_MODE_SKB_CB(skb)->protocol = ip_hdr(skb)->protocol;
|
|
|
|
return xfrm4_extract_header(skb);
|
|
}
|
|
|
|
int xfrm4_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
|
|
{
|
|
int err;
|
|
|
|
err = xfrm_inner_extract_output(x, skb);
|
|
if (err)
|
|
return err;
|
|
|
|
IPCB(skb)->flags |= IPSKB_XFRM_TUNNEL_SIZE;
|
|
skb->protocol = htons(ETH_P_IP);
|
|
|
|
return x->outer_mode->output2(x, skb);
|
|
}
|
|
EXPORT_SYMBOL(xfrm4_prepare_output);
|
|
|
|
int xfrm4_output_finish(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
|
|
|
|
IPCB(skb)->flags |= IPSKB_XFRM_TRANSFORMED;
|
|
|
|
return xfrm_output(sk, skb);
|
|
}
|
|
|
|
static int __xfrm4_output(struct net *net, struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
struct xfrm_state *x = skb_dst(skb)->xfrm;
|
|
|
|
#ifdef CONFIG_NETFILTER
|
|
if (!x) {
|
|
IPCB(skb)->flags |= IPSKB_REROUTED;
|
|
return dst_output(net, sk, skb);
|
|
}
|
|
#endif
|
|
|
|
return x->outer_mode->afinfo->output_finish(sk, skb);
|
|
}
|
|
|
|
int xfrm4_output(struct net *net, struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
|
|
net, sk, skb, NULL, skb_dst(skb)->dev,
|
|
__xfrm4_output,
|
|
!(IPCB(skb)->flags & IPSKB_REROUTED));
|
|
}
|
|
|
|
void xfrm4_local_error(struct sk_buff *skb, u32 mtu)
|
|
{
|
|
struct iphdr *hdr;
|
|
|
|
hdr = skb->encapsulation ? inner_ip_hdr(skb) : ip_hdr(skb);
|
|
ip_local_error(skb->sk, EMSGSIZE, hdr->daddr,
|
|
inet_sk(skb->sk)->inet_dport, mtu);
|
|
}
|