/***************************************************************************
   * Linux PPP over X - Generic PPP transport layer sockets
   * Linux PPP over Ethernet (PPPoE) Socket Implementation (RFC 2516) 
   *
   * This file supplies definitions required by the PPP over Ethernet driver
   * (pppox.c).  All version information wrt this file is located in pppox.c
   *
   * License:
   *		This program is free software; you can redistribute it and/or
   *		modify it under the terms of the GNU General Public License
   *		as published by the Free Software Foundation; either version
   *		2 of the License, or (at your option) any later version.
   *
   */
  
  #ifndef __LINUX_IF_PPPOX_H
  #define __LINUX_IF_PPPOX_H

  #include <linux/types.h>

  #include <asm/byteorder.h>

  #include <linux/socket.h>

  #include <linux/if_ether.h>

  #ifdef  __KERNEL__

  #include <linux/if.h>
  #include <linux/netdevice.h>

  #include <linux/ppp_channel.h>
  #endif /* __KERNEL__ */

  #include <linux/if_pppol2tp.h>

  
  /* For user-space programs to pick up these definitions
   * which they wouldn't get otherwise without defining __KERNEL__
   */
  #ifndef AF_PPPOX
  #define AF_PPPOX	24
  #define PF_PPPOX	AF_PPPOX
  #endif /* !(AF_PPPOX) */
  
  /************************************************************************ 
   * PPPoE addressing definition 
   */ 

  typedef __be16 sid_t;

  struct pppoe_addr {
  	sid_t         sid;                    /* Session identifier */
  	unsigned char remote[ETH_ALEN];       /* Remote address */
  	char          dev[IFNAMSIZ];          /* Local device to use */

  }; 
   
  /************************************************************************ 

   * PPTP addressing definition
   */
  struct pptp_addr {

  	__be16		call_id;
  	struct in_addr	sin_addr;

  };
  
  /************************************************************************
   * Protocols supported by AF_PPPOX
   */

  #define PX_PROTO_OE    0 /* Currently just PPPoE */

  #define PX_PROTO_OL2TP 1 /* Now L2TP also */

  #define PX_PROTO_PPTP  2
  #define PX_MAX_PROTO   3
  
  struct sockaddr_pppox {

  	__kernel_sa_family_t sa_family;       /* address family, AF_PPPOX */

  	unsigned int    sa_protocol;          /* protocol identifier */
  	union {
  		struct pppoe_addr  pppoe;
  		struct pptp_addr   pptp;
  	} sa_addr;

  } __attribute__((packed));

  /* The use of the above union isn't viable because the size of this
   * struct must stay fixed over time -- applications use sizeof(struct
   * sockaddr_pppox) to fill it. We use a protocol specific sockaddr
   * type instead.
   */
  struct sockaddr_pppol2tp {

  	__kernel_sa_family_t sa_family; /* address family, AF_PPPOX */

  	unsigned int    sa_protocol;    /* protocol identifier */
  	struct pppol2tp_addr pppol2tp;

  } __attribute__((packed));

  /* The L2TPv3 protocol changes tunnel and session ids from 16 to 32
   * bits. So we need a different sockaddr structure.
   */
  struct sockaddr_pppol2tpv3 {

  	__kernel_sa_family_t sa_family; /* address family, AF_PPPOX */

  	unsigned int    sa_protocol;    /* protocol identifier */
  	struct pppol2tpv3_addr pppol2tp;

  } __attribute__((packed));

  /*********************************************************************
   *
   * ioctl interface for defining forwarding of connections
   *
   ********************************************************************/
  
  #define PPPOEIOCSFWD	_IOW(0xB1 ,0, size_t)
  #define PPPOEIOCDFWD	_IO(0xB1 ,1)
  /*#define PPPOEIOCGFWD	_IOWR(0xB1,2, size_t)*/
  
  /* Codes to identify message types */
  #define PADI_CODE	0x09
  #define PADO_CODE	0x07
  #define PADR_CODE	0x19
  #define PADS_CODE	0x65
  #define PADT_CODE	0xa7
  struct pppoe_tag {

  	__be16 tag_type;
  	__be16 tag_len;

  	char tag_data[0];

  } __attribute__ ((packed));

  
  /* Tag identifiers */

  #define PTT_EOL		__cpu_to_be16(0x0000)
  #define PTT_SRV_NAME	__cpu_to_be16(0x0101)
  #define PTT_AC_NAME	__cpu_to_be16(0x0102)
  #define PTT_HOST_UNIQ	__cpu_to_be16(0x0103)
  #define PTT_AC_COOKIE	__cpu_to_be16(0x0104)
  #define PTT_VENDOR 	__cpu_to_be16(0x0105)
  #define PTT_RELAY_SID	__cpu_to_be16(0x0110)
  #define PTT_SRV_ERR     __cpu_to_be16(0x0201)
  #define PTT_SYS_ERR  	__cpu_to_be16(0x0202)
  #define PTT_GEN_ERR  	__cpu_to_be16(0x0203)

  
  struct pppoe_hdr {
  #if defined(__LITTLE_ENDIAN_BITFIELD)
  	__u8 ver : 4;
  	__u8 type : 4;
  #elif defined(__BIG_ENDIAN_BITFIELD)
  	__u8 type : 4;
  	__u8 ver : 4;
  #else
  #error	"Please fix <asm/byteorder.h>"
  #endif
  	__u8 code;

  	__be16 sid;
  	__be16 length;

  	struct pppoe_tag tag[0];

  } __attribute__((packed));

  /* Length of entire PPPoE + PPP header */
  #define PPPOE_SES_HLEN	8

  #ifdef __KERNEL__

  #include <linux/skbuff.h>
  
  static inline struct pppoe_hdr *pppoe_hdr(const struct sk_buff *skb)
  {

  	return (struct pppoe_hdr *)skb_network_header(skb);

  }

  struct pppoe_opt {
  	struct net_device      *dev;	  /* device associated with socket*/

  	int			ifindex;  /* ifindex of device associated with socket */

  	struct pppoe_addr	pa;	  /* what this socket is bound to*/
  	struct sockaddr_pppox	relay;	  /* what socket data will be
  					     relayed to (PPPoE relaying) */
  };

  struct pptp_opt {
  	struct pptp_addr src_addr;
  	struct pptp_addr dst_addr;
  	u32 ack_sent, ack_recv;
  	u32 seq_sent, seq_recv;
  	int ppp_flags;
  };

  #include <net/sock.h>
  
  struct pppox_sock {
  	/* struct sock must be the first member of pppox_sock */

  	struct sock sk;
  	struct ppp_channel chan;

  	struct pppox_sock	*next;	  /* for hash table */
  	union {
  		struct pppoe_opt pppoe;

  		struct pptp_opt  pptp;

  	} proto;

  	__be16			num;

  };
  #define pppoe_dev	proto.pppoe.dev

  #define pppoe_ifindex	proto.pppoe.ifindex

  #define pppoe_pa	proto.pppoe.pa
  #define pppoe_relay	proto.pppoe.relay
  
  static inline struct pppox_sock *pppox_sk(struct sock *sk)
  {
  	return (struct pppox_sock *)sk;
  }
  
  static inline struct sock *sk_pppox(struct pppox_sock *po)
  {
  	return (struct sock *)po;
  }
  
  struct module;
  
  struct pppox_proto {

  	int		(*create)(struct net *net, struct socket *sock);

  	int		(*ioctl)(struct socket *sock, unsigned int cmd,
  				 unsigned long arg);
  	struct module	*owner;
  };

  extern int register_pppox_proto(int proto_num, const struct pppox_proto *pp);

  extern void unregister_pppox_proto(int proto_num);
  extern void pppox_unbind_sock(struct sock *sk);/* delete ppp-channel binding */

  extern int pppox_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);

  
  /* PPPoX socket states */
  enum {
      PPPOX_NONE		= 0,  /* initial state */
      PPPOX_CONNECTED	= 1,  /* connection established ==TCP_ESTABLISHED */
      PPPOX_BOUND		= 2,  /* bound to ppp device */
      PPPOX_RELAY		= 4,  /* forwarding is enabled */
      PPPOX_ZOMBIE	= 8,  /* dead, but still bound to ppp device */
      PPPOX_DEAD		= 16  /* dead, useless, please clean me up!*/
  };
  
  #endif /* __KERNEL__ */
  
  #endif /* !(__LINUX_IF_PPPOX_H) */