The C and C++ Include Header Files

/usr/include/netinet/tcp.h


$ cat -n /usr/include/netinet/tcp.h

     1	/*
     2	 * Copyright (c) 1982, 1986, 1993
     3	 *	The Regents of the University of California.  All rights reserved.
     4	 *
     5	 * Redistribution and use in source and binary forms, with or without
     6	 * modification, are permitted provided that the following conditions
     7	 * are met:
     8	 * 1. Redistributions of source code must retain the above copyright
     9	 *    notice, this list of conditions and the following disclaimer.
    10	 * 2. Redistributions in binary form must reproduce the above copyright
    11	 *    notice, this list of conditions and the following disclaimer in the
    12	 *    documentation and/or other materials provided with the distribution.
    13	 * 4. Neither the name of the University nor the names of its contributors
    14	 *    may be used to endorse or promote products derived from this software
    15	 *    without specific prior written permission.
    16	 *
    17	 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
    18	 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    19	 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    20	 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
    21	 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
    22	 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
    23	 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
    24	 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
    25	 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
    26	 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
    27	 * SUCH DAMAGE.
    28	 *
    29	 *	@(#)tcp.h	8.1 (Berkeley) 6/10/93
    30	 */
    31	
    32	#ifndef _NETINET_TCP_H
    33	#define _NETINET_TCP_H	1
    34	
    35	#include <features.h>
    36	
    37	/*
    38	 * User-settable options (used with setsockopt).
    39	 */
    40	#define	TCP_NODELAY		 1  /* Don't delay send to coalesce packets  */
    41	#define	TCP_MAXSEG		 2  /* Set maximum segment size  */
    42	#define TCP_CORK		 3  /* Control sending of partial frames  */
    43	#define TCP_KEEPIDLE		 4  /* Start keeplives after this period */
    44	#define TCP_KEEPINTVL		 5  /* Interval between keepalives */
    45	#define TCP_KEEPCNT		 6  /* Number of keepalives before death */
    46	#define TCP_SYNCNT		 7  /* Number of SYN retransmits */
    47	#define TCP_LINGER2		 8  /* Life time of orphaned FIN-WAIT-2 state */
    48	#define TCP_DEFER_ACCEPT	 9  /* Wake up listener only when data arrive */
    49	#define TCP_WINDOW_CLAMP	 10 /* Bound advertised window */
    50	#define TCP_INFO		 11 /* Information about this connection. */
    51	#define	TCP_QUICKACK		 12 /* Bock/re-enable quick ACKs.  */
    52	#define TCP_CONGESTION		 13 /* Congestion control algorithm.  */
    53	#define TCP_MD5SIG		 14 /* TCP MD5 Signature (RFC2385) */
    54	#define TCP_COOKIE_TRANSACTIONS	 15 /* TCP Cookie Transactions */
    55	#define TCP_THIN_LINEAR_TIMEOUTS 16 /* Use linear timeouts for thin streams*/
    56	#define TCP_THIN_DUPACK		 17 /* Fast retrans. after 1 dupack */
    57	#define TCP_USER_TIMEOUT	 18 /* How long for loss retry before timeout */
    58	#define TCP_REPAIR		 19 /* TCP sock is under repair right now */
    59	#define TCP_REPAIR_QUEUE	 20 /* Set TCP queue to repair */
    60	#define TCP_QUEUE_SEQ		 21 /* Set sequence number of repaired queue. */
    61	#define TCP_REPAIR_OPTIONS	 22 /* Repair TCP connection options */
    62	#define TCP_FASTOPEN		 23 /* Enable FastOpen on listeners */
    63	#define TCP_TIMESTAMP		 24 /* TCP time stamp */
    64	#define TCP_NOTSENT_LOWAT	 25 /* Limit number of unsent bytes in
    65					       write queue.  */
    66	#define TCP_CC_INFO		 26 /* Get Congestion Control
    67					       (optional) info.  */
    68	#define TCP_SAVE_SYN		 27 /* Record SYN headers for new
    69					       connections.  */
    70	#define TCP_SAVED_SYN		 28 /* Get SYN headers recorded for
    71					       connection.  */
    72	#define TCP_REPAIR_WINDOW	 29 /* Get/set window parameters.  */
    73	#define TCP_FASTOPEN_CONNECT	 30 /* Attempt FastOpen with connect.  */
    74	#define TCP_ULP			 31 /* Attach a ULP to a TCP connection.  */
    75	#define TCP_MD5SIG_EXT		 32 /* TCP MD5 Signature with extensions.  */
    76	#define TCP_FASTOPEN_KEY	 33 /* Set the key for Fast Open (cookie).  */
    77	#define TCP_FASTOPEN_NO_COOKIE	 34 /* Enable TFO without a TFO cookie.  */
    78	#define TCP_ZEROCOPY_RECEIVE	 35
    79	#define TCP_INQ			 36 /* Notify bytes available to read
    80					       as a cmsg on read.  */
    81	#define TCP_CM_INQ		 TCP_INQ
    82	#define TCP_TX_DELAY		 37 /* Delay outgoing packets by XX usec.  */
    83	
    84	#define TCP_REPAIR_ON		 1
    85	#define TCP_REPAIR_OFF		 0
    86	#define TCP_REPAIR_OFF_NO_WP	 -1
    87	
    88	#ifdef __USE_MISC
    89	# include <sys/types.h>
    90	# include <sys/socket.h>
    91	# include <stdint.h>
    92	
    93	typedef	uint32_t tcp_seq;
    94	/*
    95	 * TCP header.
    96	 * Per RFC 793, September, 1981.
    97	 */
    98	struct tcphdr
    99	  {
   100	    __extension__ union
   101	    {
   102	      struct
   103	      {
   104		uint16_t th_sport;	/* source port */
   105		uint16_t th_dport;	/* destination port */
   106		tcp_seq th_seq;		/* sequence number */
   107		tcp_seq th_ack;		/* acknowledgement number */
   108	# if __BYTE_ORDER == __LITTLE_ENDIAN
   109		uint8_t th_x2:4;	/* (unused) */
   110		uint8_t th_off:4;	/* data offset */
   111	# endif
   112	# if __BYTE_ORDER == __BIG_ENDIAN
   113		uint8_t th_off:4;	/* data offset */
   114		uint8_t th_x2:4;	/* (unused) */
   115	# endif
   116		uint8_t th_flags;
   117	# define TH_FIN	0x01
   118	# define TH_SYN	0x02
   119	# define TH_RST	0x04
   120	# define TH_PUSH	0x08
   121	# define TH_ACK	0x10
   122	# define TH_URG	0x20
   123		uint16_t th_win;	/* window */
   124		uint16_t th_sum;	/* checksum */
   125		uint16_t th_urp;	/* urgent pointer */
   126	      };
   127	      struct
   128	      {
   129		uint16_t source;
   130		uint16_t dest;
   131		uint32_t seq;
   132		uint32_t ack_seq;
   133	# if __BYTE_ORDER == __LITTLE_ENDIAN
   134		uint16_t res1:4;
   135		uint16_t doff:4;
   136		uint16_t fin:1;
   137		uint16_t syn:1;
   138		uint16_t rst:1;
   139		uint16_t psh:1;
   140		uint16_t ack:1;
   141		uint16_t urg:1;
   142		uint16_t res2:2;
   143	# elif __BYTE_ORDER == __BIG_ENDIAN
   144		uint16_t doff:4;
   145		uint16_t res1:4;
   146		uint16_t res2:2;
   147		uint16_t urg:1;
   148		uint16_t ack:1;
   149		uint16_t psh:1;
   150		uint16_t rst:1;
   151		uint16_t syn:1;
   152		uint16_t fin:1;
   153	# else
   154	#  error "Adjust your <bits/endian.h> defines"
   155	# endif
   156		uint16_t window;
   157		uint16_t check;
   158		uint16_t urg_ptr;
   159	      };
   160	    };
   161	};
   162	
   163	enum
   164	{
   165	  TCP_ESTABLISHED = 1,
   166	  TCP_SYN_SENT,
   167	  TCP_SYN_RECV,
   168	  TCP_FIN_WAIT1,
   169	  TCP_FIN_WAIT2,
   170	  TCP_TIME_WAIT,
   171	  TCP_CLOSE,
   172	  TCP_CLOSE_WAIT,
   173	  TCP_LAST_ACK,
   174	  TCP_LISTEN,
   175	  TCP_CLOSING   /* now a valid state */
   176	};
   177	
   178	# define TCPOPT_EOL		0
   179	# define TCPOPT_NOP		1
   180	# define TCPOPT_MAXSEG		2
   181	# define TCPOLEN_MAXSEG		4
   182	# define TCPOPT_WINDOW		3
   183	# define TCPOLEN_WINDOW		3
   184	# define TCPOPT_SACK_PERMITTED	4		/* Experimental */
   185	# define TCPOLEN_SACK_PERMITTED	2
   186	# define TCPOPT_SACK		5		/* Experimental */
   187	# define TCPOPT_TIMESTAMP	8
   188	# define TCPOLEN_TIMESTAMP	10
   189	# define TCPOLEN_TSTAMP_APPA	(TCPOLEN_TIMESTAMP+2) /* appendix A */
   190	
   191	# define TCPOPT_TSTAMP_HDR	\
   192	    (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP)
   193	
   194	/*
   195	 * Default maximum segment size for TCP.
   196	 * With an IP MSS of 576, this is 536,
   197	 * but 512 is probably more convenient.
   198	 * This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)).
   199	 */
   200	# define TCP_MSS	512
   201	
   202	# define TCP_MAXWIN	65535	/* largest value for (unscaled) window */
   203	
   204	# define TCP_MAX_WINSHIFT	14	/* maximum window shift */
   205	
   206	# define SOL_TCP		6	/* TCP level */
   207	
   208	
   209	# define TCPI_OPT_TIMESTAMPS	1
   210	# define TCPI_OPT_SACK		2
   211	# define TCPI_OPT_WSCALE	4
   212	# define TCPI_OPT_ECN		8  /* ECN was negotiated at TCP session init */
   213	# define TCPI_OPT_ECN_SEEN	16 /* we received at least one packet with ECT */
   214	# define TCPI_OPT_SYN_DATA	32 /* SYN-ACK acked data in SYN sent or rcvd */
   215	
   216	/* Values for tcpi_state.  */
   217	enum tcp_ca_state
   218	{
   219	  TCP_CA_Open = 0,
   220	  TCP_CA_Disorder = 1,
   221	  TCP_CA_CWR = 2,
   222	  TCP_CA_Recovery = 3,
   223	  TCP_CA_Loss = 4
   224	};
   225	
   226	struct tcp_info
   227	{
   228	  uint8_t	tcpi_state;
   229	  uint8_t	tcpi_ca_state;
   230	  uint8_t	tcpi_retransmits;
   231	  uint8_t	tcpi_probes;
   232	  uint8_t	tcpi_backoff;
   233	  uint8_t	tcpi_options;
   234	  uint8_t	tcpi_snd_wscale : 4, tcpi_rcv_wscale : 4;
   235	
   236	  uint32_t	tcpi_rto;
   237	  uint32_t	tcpi_ato;
   238	  uint32_t	tcpi_snd_mss;
   239	  uint32_t	tcpi_rcv_mss;
   240	
   241	  uint32_t	tcpi_unacked;
   242	  uint32_t	tcpi_sacked;
   243	  uint32_t	tcpi_lost;
   244	  uint32_t	tcpi_retrans;
   245	  uint32_t	tcpi_fackets;
   246	
   247	  /* Times. */
   248	  uint32_t	tcpi_last_data_sent;
   249	  uint32_t	tcpi_last_ack_sent;	/* Not remembered, sorry.  */
   250	  uint32_t	tcpi_last_data_recv;
   251	  uint32_t	tcpi_last_ack_recv;
   252	
   253	  /* Metrics. */
   254	  uint32_t	tcpi_pmtu;
   255	  uint32_t	tcpi_rcv_ssthresh;
   256	  uint32_t	tcpi_rtt;
   257	  uint32_t	tcpi_rttvar;
   258	  uint32_t	tcpi_snd_ssthresh;
   259	  uint32_t	tcpi_snd_cwnd;
   260	  uint32_t	tcpi_advmss;
   261	  uint32_t	tcpi_reordering;
   262	
   263	  uint32_t	tcpi_rcv_rtt;
   264	  uint32_t	tcpi_rcv_space;
   265	
   266	  uint32_t	tcpi_total_retrans;
   267	};
   268	
   269	
   270	/* For TCP_MD5SIG socket option.  */
   271	#define TCP_MD5SIG_MAXKEYLEN	80
   272	
   273	/* tcp_md5sig extension flags for TCP_MD5SIG_EXT.  */
   274	#define TCP_MD5SIG_FLAG_PREFIX	1 /* Address prefix length.  */
   275	#define TCP_MD5SIG_FLAG_IFINDEX	2 /* Ifindex set.  */
   276	
   277	struct tcp_md5sig
   278	{
   279	  struct sockaddr_storage tcpm_addr;		/* Address associated.  */
   280	  uint8_t	tcpm_flags;			/* Extension flags.  */
   281	  uint8_t	tcpm_prefixlen;			/* Address prefix.  */
   282	  uint16_t	tcpm_keylen;			/* Key length.  */
   283	  int		tcpm_ifindex;			/* Device index for scope.  */
   284	  uint8_t	tcpm_key[TCP_MD5SIG_MAXKEYLEN];	/* Key (binary).  */
   285	};
   286	
   287	/* For socket repair options.  */
   288	struct tcp_repair_opt
   289	{
   290	  uint32_t	opt_code;
   291	  uint32_t	opt_val;
   292	};
   293	
   294	/* Queue to repair, for TCP_REPAIR_QUEUE.  */
   295	enum
   296	{
   297	  TCP_NO_QUEUE,
   298	  TCP_RECV_QUEUE,
   299	  TCP_SEND_QUEUE,
   300	  TCP_QUEUES_NR,
   301	};
   302	
   303	/* For cookie transactions socket options.  */
   304	#define TCP_COOKIE_MIN		8		/*  64-bits */
   305	#define TCP_COOKIE_MAX		16		/* 128-bits */
   306	#define TCP_COOKIE_PAIR_SIZE	(2*TCP_COOKIE_MAX)
   307	
   308	/* Flags for both getsockopt and setsockopt */
   309	#define TCP_COOKIE_IN_ALWAYS	(1 << 0)	/* Discard SYN without cookie */
   310	#define TCP_COOKIE_OUT_NEVER	(1 << 1)	/* Prohibit outgoing cookies,
   311							 * supersedes everything. */
   312	
   313	/* Flags for getsockopt */
   314	#define TCP_S_DATA_IN		(1 << 2)	/* Was data received? */
   315	#define TCP_S_DATA_OUT		(1 << 3)	/* Was data sent? */
   316	
   317	#define TCP_MSS_DEFAULT		 536U	/* IPv4 (RFC1122, RFC2581) */
   318	#define TCP_MSS_DESIRED		1220U	/* IPv6 (tunneled), EDNS0 (RFC3226) */
   319	
   320	struct tcp_cookie_transactions
   321	{
   322	  uint16_t	tcpct_flags;
   323	  uint8_t	__tcpct_pad1;
   324	  uint8_t	tcpct_cookie_desired;
   325	  uint16_t	tcpct_s_data_desired;
   326	  uint16_t	tcpct_used;
   327	  uint8_t	tcpct_value[TCP_MSS_DEFAULT];
   328	};
   329	
   330	/* For use with TCP_REPAIR_WINDOW.  */
   331	struct tcp_repair_window
   332	{
   333	  uint32_t snd_wl1;
   334	  uint32_t snd_wnd;
   335	  uint32_t max_window;
   336	  uint32_t rcv_wnd;
   337	  uint32_t rcv_wup;
   338	};
   339	
   340	/* For use with TCP_ZEROCOPY_RECEIVE.  */
   341	struct tcp_zerocopy_receive
   342	{
   343	  uint64_t address; /* In: address of mapping.  */
   344	  uint32_t length; /* In/out: number of bytes to map/mapped.  */
   345	  uint32_t recv_skip_hint; /* Out: amount of bytes to skip.  */
   346	};
   347	
   348	#endif /* Misc.  */
   349	
   350	#endif /* netinet/tcp.h */