alistair23-linux/net/ipv4/xfrm4_state.c
Herbert Xu 732c8bd590 [IPSEC]: Fix BEET output
The IPv6 BEET output function is incorrectly including the inner
header in the payload to be protected.  This causes a crash as
the packet doesn't actually have that many bytes for a second
header.

The IPv4 BEET output on the other hand is broken when it comes
to handling an inner IPv6 header since it always assumes an
inner IPv4 header.

This patch fixes both by making sure that neither BEET output
function touches the inner header at all.  All access is now
done through the protocol-independent cb structure.  Two new
attributes are added to make this work, the IP header length
and the IPv4 option length.  They're filled in by the inner
mode's output function.

Thanks to Joakim Koskela for finding this problem.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-26 16:51:09 -07:00

92 lines
2.2 KiB
C

/*
* xfrm4_state.c
*
* Changes:
* YOSHIFUJI Hideaki @USAGI
* Split up af-specific portion
*
*/
#include <net/ip.h>
#include <net/xfrm.h>
#include <linux/pfkeyv2.h>
#include <linux/ipsec.h>
#include <linux/netfilter_ipv4.h>
static struct xfrm_state_afinfo xfrm4_state_afinfo;
static int xfrm4_init_flags(struct xfrm_state *x)
{
if (ipv4_config.no_pmtu_disc)
x->props.flags |= XFRM_STATE_NOPMTUDISC;
return 0;
}
static void
__xfrm4_init_tempsel(struct xfrm_state *x, struct flowi *fl,
struct xfrm_tmpl *tmpl,
xfrm_address_t *daddr, xfrm_address_t *saddr)
{
x->sel.daddr.a4 = fl->fl4_dst;
x->sel.saddr.a4 = fl->fl4_src;
x->sel.dport = xfrm_flowi_dport(fl);
x->sel.dport_mask = htons(0xffff);
x->sel.sport = xfrm_flowi_sport(fl);
x->sel.sport_mask = htons(0xffff);
x->sel.prefixlen_d = 32;
x->sel.prefixlen_s = 32;
x->sel.proto = fl->proto;
x->sel.ifindex = fl->oif;
x->id = tmpl->id;
if (x->id.daddr.a4 == 0)
x->id.daddr.a4 = daddr->a4;
x->props.saddr = tmpl->saddr;
if (x->props.saddr.a4 == 0)
x->props.saddr.a4 = saddr->a4;
x->props.mode = tmpl->mode;
x->props.reqid = tmpl->reqid;
x->props.family = AF_INET;
}
int xfrm4_extract_header(struct sk_buff *skb)
{
struct iphdr *iph = ip_hdr(skb);
XFRM_MODE_SKB_CB(skb)->ihl = sizeof(*iph);
XFRM_MODE_SKB_CB(skb)->id = iph->id;
XFRM_MODE_SKB_CB(skb)->frag_off = iph->frag_off;
XFRM_MODE_SKB_CB(skb)->tos = iph->tos;
XFRM_MODE_SKB_CB(skb)->ttl = iph->ttl;
XFRM_MODE_SKB_CB(skb)->optlen = iph->ihl * 4 - sizeof(*iph);
memset(XFRM_MODE_SKB_CB(skb)->flow_lbl, 0,
sizeof(XFRM_MODE_SKB_CB(skb)->flow_lbl));
return 0;
}
static struct xfrm_state_afinfo xfrm4_state_afinfo = {
.family = AF_INET,
.proto = IPPROTO_IPIP,
.eth_proto = htons(ETH_P_IP),
.owner = THIS_MODULE,
.init_flags = xfrm4_init_flags,
.init_tempsel = __xfrm4_init_tempsel,
.output = xfrm4_output,
.extract_input = xfrm4_extract_input,
.extract_output = xfrm4_extract_output,
.transport_finish = xfrm4_transport_finish,
};
void __init xfrm4_state_init(void)
{
xfrm_state_register_afinfo(&xfrm4_state_afinfo);
}
#if 0
void __exit xfrm4_state_fini(void)
{
xfrm_state_unregister_afinfo(&xfrm4_state_afinfo);
}
#endif /* 0 */