alistair23-linux/net/ipv6/xfrm6_mode_ro.c
Herbert Xu ca68145f16 [IPSEC]: Disallow combinations of RO and AH/ESP/IPCOMP
Combining RO and AH/ESP/IPCOMP does not make sense.  So this patch adds a
check in the state initialisation function to prevent this.

This allows us to safely remove the mode input function of RO since it
can never be called anymore.  Indeed, if somehow it does get called we'll
know about it through an OOPS instead of it slipping past silently.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-17 21:35:15 -07:00

84 lines
2.3 KiB
C

/*
* xfrm6_mode_ro.c - Route optimization mode for IPv6.
*
* Copyright (C)2003-2006 Helsinki University of Technology
* Copyright (C)2003-2006 USAGI/WIDE Project
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* Authors:
* Noriaki TAKAMIYA @USAGI
* Masahide NAKAMURA @USAGI
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/stringify.h>
#include <linux/time.h>
#include <net/ipv6.h>
#include <net/xfrm.h>
/* Add route optimization header space.
*
* The IP header and mutable extension headers will be moved forward to make
* space for the route optimization header.
*/
static int xfrm6_ro_output(struct xfrm_state *x, struct sk_buff *skb)
{
struct ipv6hdr *iph;
u8 *prevhdr;
int hdr_len;
iph = ipv6_hdr(skb);
hdr_len = x->type->hdr_offset(x, skb, &prevhdr);
skb_set_mac_header(skb, (prevhdr - x->props.header_len) - skb->data);
skb_set_network_header(skb, -x->props.header_len);
skb->transport_header = skb->network_header + hdr_len;
__skb_pull(skb, hdr_len);
memmove(ipv6_hdr(skb), iph, hdr_len);
x->lastused = get_seconds();
return 0;
}
static struct xfrm_mode xfrm6_ro_mode = {
.output = xfrm6_ro_output,
.owner = THIS_MODULE,
.encap = XFRM_MODE_ROUTEOPTIMIZATION,
};
static int __init xfrm6_ro_init(void)
{
return xfrm_register_mode(&xfrm6_ro_mode, AF_INET6);
}
static void __exit xfrm6_ro_exit(void)
{
int err;
err = xfrm_unregister_mode(&xfrm6_ro_mode, AF_INET6);
BUG_ON(err);
}
module_init(xfrm6_ro_init);
module_exit(xfrm6_ro_exit);
MODULE_LICENSE("GPL");
MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_ROUTEOPTIMIZATION);