xfrm6_mode_transport.rar_Will

/* * xfrm6_mode_transport.c - Transport mode encapsulation for IPv6. * * Copyright (C) 2002 USAGI/WIDE Project * Copyright (c) 2004-2006 Herbert Xu <herbert@gondor.apana.org.au> */ #include <linux/init.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/skbuff.h> #include <linux/stringify.h> #include <net/dst.h> #include <net/ipv6.h> #include <net/xfrm.h> /* Add encapsulation header. * * The IP header and mutable extension headers will be moved forward to make * space for the encapsulation header. */ static int xfrm6_transport_output(struct xfrm_state *x, struct sk_buff *skb) { struct ipv6hdr *iph; u8 *prevhdr; int hdr_len; iph = ipv6_hdr(skb); hdr_len = x->type->hdr_offset(x, skb, &prevhdr); skb_set_mac_header(skb, (prevhdr - x->props.header_len) - skb->data); skb_set_network_header(skb, -x->props.header_len); skb->transport_header = skb->network_header + hdr_len; __skb_pull(skb, hdr_len); memmove(ipv6_hdr(skb), iph, hdr_len); return 0; } /* Remove encapsulation header. * * The IP header will be moved over the top of the encapsulation header. * * On entry, skb->h shall point to where the IP header should be and skb->nh * shall be set to where the IP header currently is. skb->data shall point * to the start of the payload. */ static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb) { int ihl = skb->data - skb_transport_header(skb); if (skb->transport_header != skb->network_header) { memmove(skb_transport_header(skb), skb_network_header(skb), ihl); skb->network_header = skb->transport_header; } ipv6_hdr(skb)->payload_len = htons(skb->len + ihl - sizeof(struct ipv6hdr)); skb_reset_transport_header(skb); return 0; } static struct xfrm_mode xfrm6_transport_mode = { .input = xfrm6_transport_input, .output = xfrm6_transport_output, .owner = THIS_MODULE, .encap = XFRM_MODE_TRANSPORT, }; static int __init xfrm6_transport_init(void) { return xfrm_register_mode(&xfrm6_transport_mode, AF_INET6); } static void __exit xfrm6_transport_exit(void) { int err; err = xfrm_unregister_mode(&xfrm6_transport_mode, AF_INET6); BUG_ON(err); } module_init(xfrm6_transport_init); module_exit(xfrm6_transport_exit); MODULE_LICENSE("GPL"); MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_TRANSPORT);