#ifndef _IF_TUNNEL_H_
  #define _IF_TUNNEL_H_

  #include <linux/types.h>

  #include <asm/byteorder.h>

  
  #ifdef __KERNEL__

  #include <linux/ip.h>

  #include <linux/in6.h>

  #endif

  #define SIOCGETTUNNEL   (SIOCDEVPRIVATE + 0)
  #define SIOCADDTUNNEL   (SIOCDEVPRIVATE + 1)
  #define SIOCDELTUNNEL   (SIOCDEVPRIVATE + 2)
  #define SIOCCHGTUNNEL   (SIOCDEVPRIVATE + 3)

  #define SIOCGETPRL      (SIOCDEVPRIVATE + 4)

  #define SIOCADDPRL      (SIOCDEVPRIVATE + 5)
  #define SIOCDELPRL      (SIOCDEVPRIVATE + 6)
  #define SIOCCHGPRL      (SIOCDEVPRIVATE + 7)

  #define SIOCGET6RD      (SIOCDEVPRIVATE + 8)
  #define SIOCADD6RD      (SIOCDEVPRIVATE + 9)
  #define SIOCDEL6RD      (SIOCDEVPRIVATE + 10)
  #define SIOCCHG6RD      (SIOCDEVPRIVATE + 11)

  #define GRE_CSUM	__cpu_to_be16(0x8000)
  #define GRE_ROUTING	__cpu_to_be16(0x4000)
  #define GRE_KEY		__cpu_to_be16(0x2000)
  #define GRE_SEQ		__cpu_to_be16(0x1000)
  #define GRE_STRICT	__cpu_to_be16(0x0800)
  #define GRE_REC		__cpu_to_be16(0x0700)
  #define GRE_FLAGS	__cpu_to_be16(0x00F8)
  #define GRE_VERSION	__cpu_to_be16(0x0007)

  struct ip_tunnel_parm {

  	char			name[IFNAMSIZ];
  	int			link;

  	__be16			i_flags;
  	__be16			o_flags;
  	__be32			i_key;
  	__be32			o_key;

  	struct iphdr		iph;
  };

  /* SIT-mode i_flags */
  #define	SIT_ISATAP	0x0001
  
  struct ip_tunnel_prl {
  	__be32			addr;
  	__u16			flags;
  	__u16			__reserved;

  	__u32			datalen;

  	__u32			__reserved2;

  	/* data follows */

  };
  
  /* PRL flags */
  #define	PRL_DEFAULT		0x0001

  struct ip_tunnel_6rd {
  	struct in6_addr		prefix;
  	__be32			relay_prefix;
  	__u16			prefixlen;
  	__u16			relay_prefixlen;
  };

  enum {

  	IFLA_GRE_UNSPEC,
  	IFLA_GRE_LINK,
  	IFLA_GRE_IFLAGS,
  	IFLA_GRE_OFLAGS,
  	IFLA_GRE_IKEY,
  	IFLA_GRE_OKEY,
  	IFLA_GRE_LOCAL,
  	IFLA_GRE_REMOTE,
  	IFLA_GRE_TTL,
  	IFLA_GRE_TOS,
  	IFLA_GRE_PMTUDISC,
  	__IFLA_GRE_MAX,
  };
  
  #define IFLA_GRE_MAX	(__IFLA_GRE_MAX - 1)

  #endif /* _IF_TUNNEL_H_ */