/*

 * Copyright (c) 1982, 1986, 1993

 *	The Regents of the University of California.  All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 4. Neither the name of the University nor the names of its contributors

 *    may be used to endorse or promote products derived from this software

 *    without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 *

 *	@(#)tcp.h	8.1 (Berkeley) 6/10/93

 */

#ifndef _NETINET_TCP_H

#define _NETINET_TCP_H	1

#include <features.h>

/*

 * User-settable options (used with setsockopt).

 */

#define	TCP_NODELAY		 1  /* Don't delay send to coalesce packets  */

#define	TCP_MAXSEG		 2  /* Set maximum segment size  */

#define TCP_CORK		 3  /* Control sending of partial frames  */

#define TCP_KEEPIDLE		 4  /* Start keeplives after this period */

#define TCP_KEEPINTVL		 5  /* Interval between keepalives */

#define TCP_KEEPCNT		 6  /* Number of keepalives before death */

#define TCP_SYNCNT		 7  /* Number of SYN retransmits */

#define TCP_LINGER2		 8  /* Life time of orphaned FIN-WAIT-2 state */

#define TCP_DEFER_ACCEPT	 9  /* Wake up listener only when data arrive */

#define TCP_WINDOW_CLAMP	 10 /* Bound advertised window */

#define TCP_INFO		 11 /* Information about this connection. */

#define	TCP_QUICKACK		 12 /* Bock/reenable quick ACKs.  */

#define TCP_CONGESTION		 13 /* Congestion control algorithm.  */

#define TCP_MD5SIG		 14 /* TCP MD5 Signature (RFC2385) */

#define TCP_COOKIE_TRANSACTIONS	 15 /* TCP Cookie Transactions */

#define TCP_THIN_LINEAR_TIMEOUTS 16 /* Use linear timeouts for thin streams*/

#define TCP_THIN_DUPACK		 17 /* Fast retrans. after 1 dupack */

#define TCP_USER_TIMEOUT	 18 /* How long for loss retry before timeout */

#define TCP_REPAIR		 19 /* TCP sock is under repair right now */

#define TCP_REPAIR_QUEUE	 20 /* Set TCP queue to repair */

#define TCP_QUEUE_SEQ		 21 /* Set sequence number of repaired queue. */

#define TCP_REPAIR_OPTIONS	 22 /* Repair TCP connection options */

#define TCP_FASTOPEN		 23 /* Enable FastOpen on listeners */

#define TCP_TIMESTAMP		 24 /* TCP time stamp */

#define TCP_NOTSENT_LOWAT	 25 /* Limit number of unsent bytes in

				       write queue.  */

#define TCP_CC_INFO		 26 /* Get Congestion Control

				       (optional) info.  */

#define TCP_SAVE_SYN		 27 /* Record SYN headers for new

				       connections.  */

#define TCP_SAVED_SYN		 28 /* Get SYN headers recorded for

				       connection.  */

#define TCP_REPAIR_WINDOW	 29 /* Get/set window parameters.  */

#define TCP_FASTOPEN_CONNECT	 30 /* Attempt FastOpen with connect.  */

#define TCP_ULP			 31 /* Attach a ULP to a TCP connection.  */

#define TCP_MD5SIG_EXT		 32 /* TCP MD5 Signature with extensions.  */

#define TCP_FASTOPEN_KEY	 33 /* Set the key for Fast Open (cookie).  */

#define TCP_FASTOPEN_NO_COOKIE	 34 /* Enable TFO without a TFO cookie.  */

#ifdef __USE_MISC

# include <sys/types.h>

# include <sys/socket.h>

# include <stdint.h>

typedef	uint32_t tcp_seq;

/*

 * TCP header.

 * Per RFC 793, September, 1981.

 */

struct tcphdr

  {

    __extension__ union

    {

      struct

      {

	uint16_t th_sport;	/* source port */

	uint16_t th_dport;	/* destination port */

	tcp_seq th_seq;		/* sequence number */

	tcp_seq th_ack;		/* acknowledgement number */

# if __BYTE_ORDER == __LITTLE_ENDIAN

	uint8_t th_x2:4;	/* (unused) */

	uint8_t th_off:4;	/* data offset */

# endif

# if __BYTE_ORDER == __BIG_ENDIAN

	uint8_t th_off:4;	/* data offset */

	uint8_t th_x2:4;	/* (unused) */

# endif

	uint8_t th_flags;

# define TH_FIN	0x01

# define TH_SYN	0x02

# define TH_RST	0x04

# define TH_PUSH	0x08

# define TH_ACK	0x10

# define TH_URG	0x20

	uint16_t th_win;	/* window */

	uint16_t th_sum;	/* checksum */

	uint16_t th_urp;	/* urgent pointer */

      };

      struct

      {

	uint16_t source;

	uint16_t dest;

	uint32_t seq;

	uint32_t ack_seq;

# if __BYTE_ORDER == __LITTLE_ENDIAN

	uint16_t res1:4;

	uint16_t doff:4;

	uint16_t fin:1;

	uint16_t syn:1;

	uint16_t rst:1;

	uint16_t psh:1;

	uint16_t ack:1;

	uint16_t urg:1;

	uint16_t res2:2;

# elif __BYTE_ORDER == __BIG_ENDIAN

	uint16_t doff:4;

	uint16_t res1:4;

	uint16_t res2:2;

	uint16_t urg:1;

	uint16_t ack:1;

	uint16_t psh:1;

	uint16_t rst:1;

	uint16_t syn:1;

	uint16_t fin:1;

# else

#  error "Adjust your <bits/endian.h> defines"

# endif

	uint16_t window;

	uint16_t check;

	uint16_t urg_ptr;

      };

    };

};

enum

{

  TCP_ESTABLISHED = 1,

  TCP_SYN_SENT,

  TCP_SYN_RECV,

  TCP_FIN_WAIT1,

  TCP_FIN_WAIT2,

  TCP_TIME_WAIT,

  TCP_CLOSE,

  TCP_CLOSE_WAIT,

  TCP_LAST_ACK,

  TCP_LISTEN,

  TCP_CLOSING   /* now a valid state */

};

# define TCPOPT_EOL		0

# define TCPOPT_NOP		1

# define TCPOPT_MAXSEG		2

# define TCPOLEN_MAXSEG		4

# define TCPOPT_WINDOW		3

# define TCPOLEN_WINDOW		3

# define TCPOPT_SACK_PERMITTED	4		/* Experimental */

# define TCPOLEN_SACK_PERMITTED	2

# define TCPOPT_SACK		5		/* Experimental */

# define TCPOPT_TIMESTAMP	8

# define TCPOLEN_TIMESTAMP	10

# define TCPOLEN_TSTAMP_APPA	(TCPOLEN_TIMESTAMP+2) /* appendix A */

# define TCPOPT_TSTAMP_HDR	\

    (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP)

/*

 * Default maximum segment size for TCP.

 * With an IP MSS of 576, this is 536,

 * but 512 is probably more convenient.

 * This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)).

 */

# define TCP_MSS	512

# define TCP_MAXWIN	65535	/* largest value for (unscaled) window */

# define TCP_MAX_WINSHIFT	14	/* maximum window shift */

# define SOL_TCP		6	/* TCP level */

# define TCPI_OPT_TIMESTAMPS	1

# define TCPI_OPT_SACK		2

# define TCPI_OPT_WSCALE	4

# define TCPI_OPT_ECN		8  /* ECN was negociated at TCP session init */

# define TCPI_OPT_ECN_SEEN	16 /* we received at least one packet with ECT */

# define TCPI_OPT_SYN_DATA	32 /* SYN-ACK acked data in SYN sent or rcvd */

/* Values for tcpi_state.  */

enum tcp_ca_state

{

  TCP_CA_Open = 0,

  TCP_CA_Disorder = 1,

  TCP_CA_CWR = 2,

  TCP_CA_Recovery = 3,

  TCP_CA_Loss = 4

};

struct tcp_info

{

  uint8_t	tcpi_state;

  uint8_t	tcpi_ca_state;

  uint8_t	tcpi_retransmits;

  uint8_t	tcpi_probes;

  uint8_t	tcpi_backoff;

  uint8_t	tcpi_options;

  uint8_t	tcpi_snd_wscale : 4, tcpi_rcv_wscale : 4;

  uint32_t	tcpi_rto;

  uint32_t	tcpi_ato;

  uint32_t	tcpi_snd_mss;

  uint32_t	tcpi_rcv_mss;

  uint32_t	tcpi_unacked;

  uint32_t	tcpi_sacked;

  uint32_t	tcpi_lost;

  uint32_t	tcpi_retrans;

  uint32_t	tcpi_fackets;

  /* Times. */

  uint32_t	tcpi_last_data_sent;

  uint32_t	tcpi_last_ack_sent;	/* Not remembered, sorry.  */

  uint32_t	tcpi_last_data_recv;

  uint32_t	tcpi_last_ack_recv;

  /* Metrics. */

  uint32_t	tcpi_pmtu;

  uint32_t	tcpi_rcv_ssthresh;

  uint32_t	tcpi_rtt;

  uint32_t	tcpi_rttvar;

  uint32_t	tcpi_snd_ssthresh;

  uint32_t	tcpi_snd_cwnd;

  uint32_t	tcpi_advmss;

  uint32_t	tcpi_reordering;

  uint32_t	tcpi_rcv_rtt;

  uint32_t	tcpi_rcv_space;

  uint32_t	tcpi_total_retrans;

};

/* For TCP_MD5SIG socket option.  */

#define TCP_MD5SIG_MAXKEYLEN	80

/* tcp_md5sig extension flags for TCP_MD5SIG_EXT.  */

#define TCP_MD5SIG_FLAG_PREFIX	1 /* Address prefix length.  */

struct tcp_md5sig

{

  struct sockaddr_storage tcpm_addr;		/* Address associated.  */

  uint8_t	tcpm_flags;			/* Extension flags.  */

  uint8_t	tcpm_prefixlen;			/* Address prefix.  */

  uint16_t	tcpm_keylen;			/* Key length.  */

  uint32_t	__tcpm_pad;			/* Zero.  */

  uint8_t	tcpm_key[TCP_MD5SIG_MAXKEYLEN];	/* Key (binary).  */

};

/* For socket repair options.  */

struct tcp_repair_opt

{

  uint32_t	opt_code;

  uint32_t	opt_val;

};

/* Queue to repair, for TCP_REPAIR_QUEUE.  */

enum

{

  TCP_NO_QUEUE,

  TCP_RECV_QUEUE,

  TCP_SEND_QUEUE,

  TCP_QUEUES_NR,

};

/* For cookie transactions socket options.  */

#define TCP_COOKIE_MIN		8		/*  64-bits */

#define TCP_COOKIE_MAX		16		/* 128-bits */

#define TCP_COOKIE_PAIR_SIZE	(2*TCP_COOKIE_MAX)

/* Flags for both getsockopt and setsockopt */

#define TCP_COOKIE_IN_ALWAYS	(1 << 0)	/* Discard SYN without cookie */

#define TCP_COOKIE_OUT_NEVER	(1 << 1)	/* Prohibit outgoing cookies,

						 * supercedes everything. */

/* Flags for getsockopt */

#define TCP_S_DATA_IN		(1 << 2)	/* Was data received? */

#define TCP_S_DATA_OUT		(1 << 3)	/* Was data sent? */

#define TCP_MSS_DEFAULT		 536U	/* IPv4 (RFC1122, RFC2581) */

#define TCP_MSS_DESIRED		1220U	/* IPv6 (tunneled), EDNS0 (RFC3226) */

struct tcp_cookie_transactions

{

  uint16_t	tcpct_flags;

  uint8_t	__tcpct_pad1;

  uint8_t	tcpct_cookie_desired;

  uint16_t	tcpct_s_data_desired;

  uint16_t	tcpct_used;

  uint8_t	tcpct_value[TCP_MSS_DEFAULT];

};

/* For use with TCP_REPAIR_WINDOW.  */

struct tcp_repair_window

{

  uint32_t snd_wl1;

  uint32_t snd_wnd;

  uint32_t max_window;

  uint32_t rcv_wnd;

  uint32_t rcv_wup;

};

#endif /* Misc.  */

#endif /* netinet/tcp.h */