/*
 * 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) */

#ifdef __USE_MISC
# include <sys/types.h>
# include <sys/socket.h>

# ifdef __FAVOR_BSD
typedef        u_int32_t tcp_seq;
/*
 * TCP header.
 * Per RFC 793, September, 1981.
 */
struct tcphdr
  {
    u_int16_t th_sport;                /* source port */
    u_int16_t th_dport;                /* destination port */
    tcp_seq th_seq;                /* sequence number */
    tcp_seq th_ack;                /* acknowledgement number */
#  if __BYTE_ORDER == __LITTLE_ENDIAN
    u_int8_t th_x2:4;                /* (unused) */
    u_int8_t th_off:4;                /* data offset */
#  endif
#  if __BYTE_ORDER == __BIG_ENDIAN
    u_int8_t th_off:4;                /* data offset */
    u_int8_t th_x2:4;                /* (unused) */
#  endif
    u_int8_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
    u_int16_t th_win;                /* window */
    u_int16_t th_sum;                /* checksum */
    u_int16_t th_urp;                /* urgent pointer */
};

# else /* !__FAVOR_BSD */
struct tcphdr
  {
    u_int16_t source;
    u_int16_t dest;
    u_int32_t seq;
    u_int32_t ack_seq;
#  if __BYTE_ORDER == __LITTLE_ENDIAN
    u_int16_t res1:4;
    u_int16_t doff:4;
    u_int16_t fin:1;
    u_int16_t syn:1;
    u_int16_t rst:1;
    u_int16_t psh:1;
    u_int16_t ack:1;
    u_int16_t urg:1;
    u_int16_t res2:2;
#  elif __BYTE_ORDER == __BIG_ENDIAN
    u_int16_t doff:4;
    u_int16_t res1:4;
    u_int16_t res2:2;
    u_int16_t urg:1;
    u_int16_t ack:1;
    u_int16_t psh:1;
    u_int16_t rst:1;
    u_int16_t syn:1;
    u_int16_t fin:1;
#  else
#   error "Adjust your <bits/endian.h> defines"
#  endif
    u_int16_t window;
    u_int16_t check;
    u_int16_t urg_ptr;
};
# endif /* __FAVOR_BSD */

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

/* 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
{
  u_int8_t        tcpi_state;
  u_int8_t        tcpi_ca_state;
  u_int8_t        tcpi_retransmits;
  u_int8_t        tcpi_probes;
  u_int8_t        tcpi_backoff;
  u_int8_t        tcpi_options;
  u_int8_t        tcpi_snd_wscale : 4, tcpi_rcv_wscale : 4;

  u_int32_t        tcpi_rto;
  u_int32_t        tcpi_ato;
  u_int32_t        tcpi_snd_mss;
  u_int32_t        tcpi_rcv_mss;

  u_int32_t        tcpi_unacked;
  u_int32_t        tcpi_sacked;
  u_int32_t        tcpi_lost;
  u_int32_t        tcpi_retrans;
  u_int32_t        tcpi_fackets;

  /* Times. */
  u_int32_t        tcpi_last_data_sent;
  u_int32_t        tcpi_last_ack_sent;        /* Not remembered, sorry.  */
  u_int32_t        tcpi_last_data_recv;
  u_int32_t        tcpi_last_ack_recv;

  /* Metrics. */
  u_int32_t        tcpi_pmtu;
  u_int32_t        tcpi_rcv_ssthresh;
  u_int32_t        tcpi_rtt;
  u_int32_t        tcpi_rttvar;
  u_int32_t        tcpi_snd_ssthresh;
  u_int32_t        tcpi_snd_cwnd;
  u_int32_t        tcpi_advmss;
  u_int32_t        tcpi_reordering;

  u_int32_t        tcpi_rcv_rtt;
  u_int32_t        tcpi_rcv_space;

  u_int32_t        tcpi_total_retrans;
};


/* For TCP_MD5SIG socket option.  */
#define TCP_MD5SIG_MAXKEYLEN        80

struct tcp_md5sig
{
  struct sockaddr_storage tcpm_addr;                /* Address associated.  */
  u_int16_t        __tcpm_pad1;                        /* Zero.  */
  u_int16_t        tcpm_keylen;                        /* Key length.  */
  u_int32_t        __tcpm_pad2;                        /* Zero.  */
  u_int8_t        tcpm_key[TCP_MD5SIG_MAXKEYLEN];        /* Key (binary).  */
};

#endif /* Misc.  */

#endif /* netinet/tcp.h */