diff options
author | Herbert Xu <herbert@gondor.apana.org.au> | 2006-05-28 02:05:54 -0400 |
---|---|---|
committer | David S. Miller <davem@sunset.davemloft.net> | 2006-06-18 00:28:39 -0400 |
commit | b59f45d0b2878ab76f8053b0973654e6621828ee (patch) | |
tree | 40dc5e2ede2620f7935fb3dae0d0eb199851f611 /net/ipv6/xfrm6_mode_transport.c | |
parent | 546be2405be119ef55467aace45f337a16e5d424 (diff) |
[IPSEC] xfrm: Abstract out encapsulation modes
This patch adds the structure xfrm_mode. It is meant to represent
the operations carried out by transport/tunnel modes.
By doing this we allow additional encapsulation modes to be added
without clogging up the xfrm_input/xfrm_output paths.
Candidate modes include 4-to-6 tunnel mode, 6-to-4 tunnel mode, and
BEET modes.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6/xfrm6_mode_transport.c')
-rw-r--r-- | net/ipv6/xfrm6_mode_transport.c | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/net/ipv6/xfrm6_mode_transport.c b/net/ipv6/xfrm6_mode_transport.c new file mode 100644 index 00000000000..5efbbae08ef --- /dev/null +++ b/net/ipv6/xfrm6_mode_transport.c | |||
@@ -0,0 +1,73 @@ | |||
1 | /* | ||
2 | * xfrm6_mode_transport.c - Transport mode encapsulation for IPv6. | ||
3 | * | ||
4 | * Copyright (C) 2002 USAGI/WIDE Project | ||
5 | * Copyright (c) 2004-2006 Herbert Xu <herbert@gondor.apana.org.au> | ||
6 | */ | ||
7 | |||
8 | #include <linux/init.h> | ||
9 | #include <linux/kernel.h> | ||
10 | #include <linux/module.h> | ||
11 | #include <linux/skbuff.h> | ||
12 | #include <linux/stringify.h> | ||
13 | #include <net/dst.h> | ||
14 | #include <net/ipv6.h> | ||
15 | #include <net/xfrm.h> | ||
16 | |||
17 | /* Add encapsulation header. | ||
18 | * | ||
19 | * The IP header and mutable extension headers will be moved forward to make | ||
20 | * space for the encapsulation header. | ||
21 | * | ||
22 | * On exit, skb->h will be set to the start of the encapsulation header to be | ||
23 | * filled in by x->type->output and skb->nh will be set to the nextheader field | ||
24 | * of the extension header directly preceding the encapsulation header, or in | ||
25 | * its absence, that of the top IP header. The value of skb->data will always | ||
26 | * point to the top IP header. | ||
27 | */ | ||
28 | static int xfrm6_transport_output(struct sk_buff *skb) | ||
29 | { | ||
30 | struct xfrm_state *x = skb->dst->xfrm; | ||
31 | struct ipv6hdr *iph; | ||
32 | u8 *prevhdr; | ||
33 | int hdr_len; | ||
34 | |||
35 | skb_push(skb, x->props.header_len); | ||
36 | iph = skb->nh.ipv6h; | ||
37 | |||
38 | hdr_len = ip6_find_1stfragopt(skb, &prevhdr); | ||
39 | skb->nh.raw = prevhdr - x->props.header_len; | ||
40 | skb->h.raw = skb->data + hdr_len; | ||
41 | memmove(skb->data, iph, hdr_len); | ||
42 | return 0; | ||
43 | } | ||
44 | |||
45 | static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb) | ||
46 | { | ||
47 | return 0; | ||
48 | } | ||
49 | |||
50 | static struct xfrm_mode xfrm6_transport_mode = { | ||
51 | .input = xfrm6_transport_input, | ||
52 | .output = xfrm6_transport_output, | ||
53 | .owner = THIS_MODULE, | ||
54 | .encap = XFRM_MODE_TRANSPORT, | ||
55 | }; | ||
56 | |||
57 | static int __init xfrm6_transport_init(void) | ||
58 | { | ||
59 | return xfrm_register_mode(&xfrm6_transport_mode, AF_INET6); | ||
60 | } | ||
61 | |||
62 | static void __exit xfrm6_transport_exit(void) | ||
63 | { | ||
64 | int err; | ||
65 | |||
66 | err = xfrm_unregister_mode(&xfrm6_transport_mode, AF_INET6); | ||
67 | BUG_ON(err); | ||
68 | } | ||
69 | |||
70 | module_init(xfrm6_transport_init); | ||
71 | module_exit(xfrm6_transport_exit); | ||
72 | MODULE_LICENSE("GPL"); | ||
73 | MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_TRANSPORT); | ||