linux/include/linux/netfilter/nf_conntrack_proto_gre.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _CONNTRACK_PROTO_GRE_H
#define _CONNTRACK_PROTO_GRE_H
#include <asm/byteorder.h>
#include <net/gre.h>
#include <net/pptp.h>

struct nf_ct_gre { … };

#include <net/netfilter/nf_conntrack_tuple.h>

struct nf_conn;

/* structure for original <-> reply keymap */
struct nf_ct_gre_keymap { … };

/* add new tuple->key_reply pair to keymap */
int nf_ct_gre_keymap_add(struct nf_conn *ct, enum ip_conntrack_dir dir,
			 struct nf_conntrack_tuple *t);

/* delete keymap entries */
void nf_ct_gre_keymap_destroy(struct nf_conn *ct);

bool gre_pkt_to_tuple(const struct sk_buff *skb, unsigned int dataoff,
		      struct net *net, struct nf_conntrack_tuple *tuple);
#endif /* _CONNTRACK_PROTO_GRE_H */