[net-next-2.6.git] / net / ipv6 / xfrm6_mode_ro.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 <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.
 *
 * On exit, skb->h will be set to the start of the encapsulation header to be
 * filled in by x->type->output and skb->nh will be set to the nextheader field
 * of the extension header directly preceding the encapsulation header, or in
 * its absence, that of the top IP header.  The value of skb->data will always
 * point to the top IP header.
 */
static int xfrm6_ro_output(struct xfrm_state *x, struct sk_buff *skb)
{
	struct ipv6hdr *iph;
	u8 *prevhdr;
	int hdr_len;

	skb_push(skb, x->props.header_len);
	iph = ipv6_hdr(skb);

	hdr_len = x->type->hdr_offset(x, skb, &prevhdr);
	skb->nh.raw = prevhdr - x->props.header_len;
	skb_set_transport_header(skb, hdr_len);
	memmove(skb->data, iph, hdr_len);
	return 0;
}

/*
 * Do nothing about routing optimization header unlike IPsec.
 */
static int xfrm6_ro_input(struct xfrm_state *x, struct sk_buff *skb)
{
	return 0;
}

static struct xfrm_mode xfrm6_ro_mode = {
	.input = xfrm6_ro_input,
	.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);
Commit	Line	Data
1d71627d MN	1	/*
	2	* xfrm6_mode_ro.c - Route optimization mode for IPv6.
	3	*
	4	* Copyright (C)2003-2006 Helsinki University of Technology
	5	* Copyright (C)2003-2006 USAGI/WIDE Project
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published by
	9	* the Free Software Foundation; either version 2 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This program is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	* GNU General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU General Public License
	18	* along with this program; if not, write to the Free Software
	19	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	20	*/
	21	/*
	22	* Authors:
	23	* Noriaki TAKAMIYA @USAGI
	24	* Masahide NAKAMURA @USAGI
	25	*/
	26
	27	#include <linux/init.h>
	28	#include <linux/kernel.h>
	29	#include <linux/module.h>
	30	#include <linux/skbuff.h>
	31	#include <linux/stringify.h>
	32	#include <net/ipv6.h>
	33	#include <net/xfrm.h>
	34
	35	/* Add route optimization header space.
	36	*
	37	* The IP header and mutable extension headers will be moved forward to make
	38	* space for the route optimization header.
	39	*
	40	* On exit, skb->h will be set to the start of the encapsulation header to be
	41	* filled in by x->type->output and skb->nh will be set to the nextheader field
	42	* of the extension header directly preceding the encapsulation header, or in
	43	* its absence, that of the top IP header. The value of skb->data will always
	44	* point to the top IP header.
	45	*/
eb878e84	46	static int xfrm6_ro_output(struct xfrm_state x, struct sk_buff skb)
1d71627d	47	{
1d71627d MN	48	struct ipv6hdr *iph;
	49	u8 *prevhdr;
	50	int hdr_len;
	51
	52	skb_push(skb, x->props.header_len);
0660e03f	53	iph = ipv6_hdr(skb);
1d71627d MN	54
	55	hdr_len = x->type->hdr_offset(x, skb, &prevhdr);
	56	skb->nh.raw = prevhdr - x->props.header_len;
967b05f6	57	skb_set_transport_header(skb, hdr_len);
1d71627d MN	58	memmove(skb->data, iph, hdr_len);
	59	return 0;
	60	}
	61
	62	/*
	63	* Do nothing about routing optimization header unlike IPsec.
	64	*/
	65	static int xfrm6_ro_input(struct xfrm_state x, struct sk_buff skb)
	66	{
	67	return 0;
	68	}
	69
	70	static struct xfrm_mode xfrm6_ro_mode = {
	71	.input = xfrm6_ro_input,
	72	.output = xfrm6_ro_output,
	73	.owner = THIS_MODULE,
	74	.encap = XFRM_MODE_ROUTEOPTIMIZATION,
	75	};
	76
	77	static int __init xfrm6_ro_init(void)
	78	{
	79	return xfrm_register_mode(&xfrm6_ro_mode, AF_INET6);
	80	}
	81
	82	static void __exit xfrm6_ro_exit(void)
	83	{
	84	int err;
	85
	86	err = xfrm_unregister_mode(&xfrm6_ro_mode, AF_INET6);
	87	BUG_ON(err);
	88	}
	89
	90	module_init(xfrm6_ro_init);
	91	module_exit(xfrm6_ro_exit);
	92	MODULE_LICENSE("GPL");
	93	MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_ROUTEOPTIMIZATION);