projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| b59f45d0 HX |
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 | */ | |
| eb878e84 | 28 | static int xfrm6_transport_output(struct xfrm_state *x, struct sk_buff *skb) |
| b59f45d0 | 29 | { |
| b59f45d0 HX |
30 | struct ipv6hdr *iph; |
| 31 | u8 *prevhdr; | |
| 32 | int hdr_len; | |
| 33 | ||
| 34 | skb_push(skb, x->props.header_len); | |
| 0660e03f | 35 | iph = ipv6_hdr(skb); |
| b59f45d0 | 36 | |
| aee5adb4 | 37 | hdr_len = x->type->hdr_offset(x, skb, &prevhdr); |
| b59f45d0 | 38 | skb->nh.raw = prevhdr - x->props.header_len; |
| 967b05f6 | 39 | skb_set_transport_header(skb, hdr_len); |
| b59f45d0 HX |
40 | memmove(skb->data, iph, hdr_len); |
| 41 | return 0; | |
| 42 | } | |
| 43 | ||
| 31a4ab93 HX |
44 | /* Remove encapsulation header. |
| 45 | * | |
| 46 | * The IP header will be moved over the top of the encapsulation header. | |
| 47 | * | |
| 48 | * On entry, skb->h shall point to where the IP header should be and skb->nh | |
| 49 | * shall be set to where the IP header currently is. skb->data shall point | |
| 50 | * to the start of the payload. | |
| 51 | */ | |
| b59f45d0 HX |
52 | static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb) |
| 53 | { | |
| 9c70220b | 54 | int ihl = skb->data - skb_transport_header(skb); |
| 31a4ab93 | 55 | |
| d56f90a7 | 56 | if (skb->h.raw != skb->nh.raw) { |
| 9c70220b ACM |
57 | memmove(skb_transport_header(skb), |
| 58 | skb_network_header(skb), ihl); | |
| d56f90a7 ACM |
59 | skb->nh.raw = skb->h.raw; |
| 60 | } | |
| 0660e03f | 61 | ipv6_hdr(skb)->payload_len = htons(skb->len + ihl - |
| 31a4ab93 | 62 | sizeof(struct ipv6hdr)); |
| badff6d0 | 63 | skb_reset_transport_header(skb); |
| b59f45d0 HX |
64 | return 0; |
| 65 | } | |
| 66 | ||
| 67 | static struct xfrm_mode xfrm6_transport_mode = { | |
| 68 | .input = xfrm6_transport_input, | |
| 69 | .output = xfrm6_transport_output, | |
| 70 | .owner = THIS_MODULE, | |
| 71 | .encap = XFRM_MODE_TRANSPORT, | |
| 72 | }; | |
| 73 | ||
| 74 | static int __init xfrm6_transport_init(void) | |
| 75 | { | |
| 76 | return xfrm_register_mode(&xfrm6_transport_mode, AF_INET6); | |
| 77 | } | |
| 78 | ||
| 79 | static void __exit xfrm6_transport_exit(void) | |
| 80 | { | |
| 81 | int err; | |
| 82 | ||
| 83 | err = xfrm_unregister_mode(&xfrm6_transport_mode, AF_INET6); | |
| 84 | BUG_ON(err); | |
| 85 | } | |
| 86 | ||
| 87 | module_init(xfrm6_transport_init); | |
| 88 | module_exit(xfrm6_transport_exit); | |
| 89 | MODULE_LICENSE("GPL"); | |
| 90 | MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_TRANSPORT); |