projects / 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 <[email protected]> | |
| 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. | |
| b59f45d0 | 21 | */ |
| eb878e84 | 22 | static int xfrm6_transport_output(struct xfrm_state *x, struct sk_buff *skb) |
| b59f45d0 | 23 | { |
| b59f45d0 HX |
24 | struct ipv6hdr *iph; |
| 25 | u8 *prevhdr; | |
| 26 | int hdr_len; | |
| 27 | ||
| 0660e03f | 28 | iph = ipv6_hdr(skb); |
| b59f45d0 | 29 | |
| aee5adb4 | 30 | hdr_len = x->type->hdr_offset(x, skb, &prevhdr); |
| 007f0211 | 31 | skb_set_mac_header(skb, (prevhdr - x->props.header_len) - skb->data); |
| 7b277b1a | 32 | skb_set_network_header(skb, -x->props.header_len); |
| 37fedd3a | 33 | skb->transport_header = skb->network_header + hdr_len; |
| 7b277b1a HX |
34 | __skb_pull(skb, hdr_len); |
| 35 | memmove(ipv6_hdr(skb), iph, hdr_len); | |
| b59f45d0 HX |
36 | return 0; |
| 37 | } | |
| 38 | ||
| 31a4ab93 HX |
39 | /* Remove encapsulation header. |
| 40 | * | |
| 41 | * The IP header will be moved over the top of the encapsulation header. | |
| 42 | * | |
| 43 | * On entry, skb->h shall point to where the IP header should be and skb->nh | |
| 44 | * shall be set to where the IP header currently is. skb->data shall point | |
| 45 | * to the start of the payload. | |
| 46 | */ | |
| b59f45d0 HX |
47 | static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb) |
| 48 | { | |
| 9c70220b | 49 | int ihl = skb->data - skb_transport_header(skb); |
| 31a4ab93 | 50 | |
| b0e380b1 | 51 | if (skb->transport_header != skb->network_header) { |
| 9c70220b ACM |
52 | memmove(skb_transport_header(skb), |
| 53 | skb_network_header(skb), ihl); | |
| b0e380b1 | 54 | skb->network_header = skb->transport_header; |
| d56f90a7 | 55 | } |
| 0660e03f | 56 | ipv6_hdr(skb)->payload_len = htons(skb->len + ihl - |
| 31a4ab93 | 57 | sizeof(struct ipv6hdr)); |
| badff6d0 | 58 | skb_reset_transport_header(skb); |
| b59f45d0 HX |
59 | return 0; |
| 60 | } | |
| 61 | ||
| 62 | static struct xfrm_mode xfrm6_transport_mode = { | |
| 63 | .input = xfrm6_transport_input, | |
| 64 | .output = xfrm6_transport_output, | |
| 65 | .owner = THIS_MODULE, | |
| 66 | .encap = XFRM_MODE_TRANSPORT, | |
| 67 | }; | |
| 68 | ||
| 69 | static int __init xfrm6_transport_init(void) | |
| 70 | { | |
| 71 | return xfrm_register_mode(&xfrm6_transport_mode, AF_INET6); | |
| 72 | } | |
| 73 | ||
| 74 | static void __exit xfrm6_transport_exit(void) | |
| 75 | { | |
| 76 | int err; | |
| 77 | ||
| 78 | err = xfrm_unregister_mode(&xfrm6_transport_mode, AF_INET6); | |
| 79 | BUG_ON(err); | |
| 80 | } | |
| 81 | ||
| 82 | module_init(xfrm6_transport_init); | |
| 83 | module_exit(xfrm6_transport_exit); | |
| 84 | MODULE_LICENSE("GPL"); | |
| 85 | MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_TRANSPORT); |