1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
|
/*
* xfrm6_mode_beet.c - BEET mode encapsulation for IPv6.
*
* Copyright (c) 2006 Diego Beltrami <diego.beltrami@gmail.com>
* Miika Komu <miika@iki.fi>
* Herbert Xu <herbert@gondor.apana.org.au>
* Abhinav Pathak <abhinav.pathak@hiit.fi>
* Jeff Ahrenholz <ahrenholz@gmail.com>
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/stringify.h>
#include <net/dsfield.h>
#include <net/dst.h>
#include <net/inet_ecn.h>
#include <net/ipv6.h>
#include <net/xfrm.h>
/* Add encapsulation header.
*
* The top IP header will be constructed per draft-nikander-esp-beet-mode-06.txt.
* The following fields in it shall be filled in by x->type->output:
* payload_len
*
* 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_beet_output(struct xfrm_state *x, struct sk_buff *skb)
{
struct ipv6hdr *iph, *top_iph;
u8 *prevhdr;
int hdr_len;
skb_push(skb, x->props.header_len);
iph = skb->nh.ipv6h;
hdr_len = ip6_find_1stfragopt(skb, &prevhdr);
skb->nh.raw = prevhdr - x->props.header_len;
skb->h.raw = skb->data + hdr_len;
memmove(skb->data, iph, hdr_len);
skb_reset_network_header(skb);
top_iph = skb->nh.ipv6h;
skb->nh.raw = &top_iph->nexthdr;
skb->h.ipv6h = top_iph + 1;
ipv6_addr_copy(&top_iph->saddr, (struct in6_addr *)&x->props.saddr);
ipv6_addr_copy(&top_iph->daddr, (struct in6_addr *)&x->id.daddr);
return 0;
}
static int xfrm6_beet_input(struct xfrm_state *x, struct sk_buff *skb)
{
struct ipv6hdr *ip6h;
const unsigned char *old_mac;
int size = sizeof(struct ipv6hdr);
int err = -EINVAL;
if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
goto out;
skb_push(skb, size);
memmove(skb->data, skb->nh.raw, size);
skb_reset_network_header(skb);
old_mac = skb_mac_header(skb);
skb_set_mac_header(skb, -skb->mac_len);
memmove(skb_mac_header(skb), old_mac, skb->mac_len);
ip6h = skb->nh.ipv6h;
ip6h->payload_len = htons(skb->len - size);
ipv6_addr_copy(&ip6h->daddr, (struct in6_addr *) &x->sel.daddr.a6);
ipv6_addr_copy(&ip6h->saddr, (struct in6_addr *) &x->sel.saddr.a6);
err = 0;
out:
return err;
}
static struct xfrm_mode xfrm6_beet_mode = {
.input = xfrm6_beet_input,
.output = xfrm6_beet_output,
.owner = THIS_MODULE,
.encap = XFRM_MODE_BEET,
};
static int __init xfrm6_beet_init(void)
{
return xfrm_register_mode(&xfrm6_beet_mode, AF_INET6);
}
static void __exit xfrm6_beet_exit(void)
{
int err;
err = xfrm_unregister_mode(&xfrm6_beet_mode, AF_INET6);
BUG_ON(err);
}
module_init(xfrm6_beet_init);
module_exit(xfrm6_beet_exit);
MODULE_LICENSE("GPL");
MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_BEET);
|
