2 * xfrm6_mode_ro.c - Route optimization mode for IPv6.
4 * Copyright (C)2003-2006 Helsinki University of Technology
5 * Copyright (C)2003-2006 USAGI/WIDE Project
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.
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.
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
23 * Noriaki TAKAMIYA @USAGI
24 * Masahide NAKAMURA @USAGI
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 <linux/time.h>
36 /* Add route optimization header space.
38 * The IP header and mutable extension headers will be moved forward to make
39 * space for the route optimization header.
41 * On exit, skb->h will be set to the start of the encapsulation header to be
42 * filled in by x->type->output and the mac header will be set to the
43 * nextheader field of the extension header directly preceding the
44 * encapsulation header, or in its absence, that of the top IP header.
45 * The value of skb->data and the network header will always point to the
48 static int xfrm6_ro_output(struct xfrm_state
*x
, struct sk_buff
*skb
)
54 skb_push(skb
, x
->props
.header_len
);
57 hdr_len
= x
->type
->hdr_offset(x
, skb
, &prevhdr
);
58 skb_set_mac_header(skb
, (prevhdr
- x
->props
.header_len
) - skb
->data
);
59 skb_reset_network_header(skb
);
60 skb_set_transport_header(skb
, hdr_len
);
61 memmove(skb
->data
, iph
, hdr_len
);
63 x
->lastused
= get_seconds();
69 * Do nothing about routing optimization header unlike IPsec.
71 static int xfrm6_ro_input(struct xfrm_state
*x
, struct sk_buff
*skb
)
76 static struct xfrm_mode xfrm6_ro_mode
= {
77 .input
= xfrm6_ro_input
,
78 .output
= xfrm6_ro_output
,
80 .encap
= XFRM_MODE_ROUTEOPTIMIZATION
,
83 static int __init
xfrm6_ro_init(void)
85 return xfrm_register_mode(&xfrm6_ro_mode
, AF_INET6
);
88 static void __exit
xfrm6_ro_exit(void)
92 err
= xfrm_unregister_mode(&xfrm6_ro_mode
, AF_INET6
);
96 module_init(xfrm6_ro_init
);
97 module_exit(xfrm6_ro_exit
);
98 MODULE_LICENSE("GPL");
99 MODULE_ALIAS_XFRM_MODE(AF_INET6
, XFRM_MODE_ROUTEOPTIMIZATION
);