/*
* 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 */