#ifndef _NET_IPCOMP_H#define _NET_IPCOMP_H #include <linux/types.h> #define IPCOMP_SCRATCH_SIZE     65400 struct crypto_comp; struct ipcomp_data {	u16 threshold;	struct crypto_comp * __percpu *tfms;}; struct ip_comp_hdr;struct sk_buff;struct xfrm_state; int ipcomp_input(struct xfrm_state *x, struct sk_buff *skb);int ipcomp_output(struct xfrm_state *x, struct sk_buff *skb);void ipcomp_destroy(struct xfrm_state *x);int ipcomp_init_state(struct xfrm_state *x); static inline struct ip_comp_hdr *ip_comp_hdr(const struct sk_buff *skb){	return (struct ip_comp_hdr *)skb_transport_header(skb);} #endif