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
 93typedef	uint32_t tcp_seq;
 94/*
 95 * TCP header.
 96 * Per RFC 793, September, 1981.
 97 */
 98struct 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
163enum
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# define TCPI_OPT_USEC_TS	64 /* usec timestamps */
216# define TCPI_OPT_TFO_CHILD	128 /* child from a Fast Open option on SYN */
217
218
219/* Values for tcpi_state.  */
220enum tcp_ca_state
221{
222  TCP_CA_Open = 0,
223  TCP_CA_Disorder = 1,
224  TCP_CA_CWR = 2,
225  TCP_CA_Recovery = 3,
226  TCP_CA_Loss = 4
227};
228
229struct tcp_info
230{
231  uint8_t	tcpi_state;
232  uint8_t	tcpi_ca_state;
233  uint8_t	tcpi_retransmits;
234  uint8_t	tcpi_probes;
235  uint8_t	tcpi_backoff;
236  uint8_t	tcpi_options;
237  uint8_t	tcpi_snd_wscale : 4, tcpi_rcv_wscale : 4;
238
239  uint32_t	tcpi_rto;
240  uint32_t	tcpi_ato;
241  uint32_t	tcpi_snd_mss;
242  uint32_t	tcpi_rcv_mss;
243
244  uint32_t	tcpi_unacked;
245  uint32_t	tcpi_sacked;
246  uint32_t	tcpi_lost;
247  uint32_t	tcpi_retrans;
248  uint32_t	tcpi_fackets;
249
250  /* Times. */
251  uint32_t	tcpi_last_data_sent;
252  uint32_t	tcpi_last_ack_sent;	/* Not remembered, sorry.  */
253  uint32_t	tcpi_last_data_recv;
254  uint32_t	tcpi_last_ack_recv;
255
256  /* Metrics. */
257  uint32_t	tcpi_pmtu;
258  uint32_t	tcpi_rcv_ssthresh;
259  uint32_t	tcpi_rtt;
260  uint32_t	tcpi_rttvar;
261  uint32_t	tcpi_snd_ssthresh;
262  uint32_t	tcpi_snd_cwnd;
263  uint32_t	tcpi_advmss;
264  uint32_t	tcpi_reordering;
265
266  uint32_t	tcpi_rcv_rtt;
267  uint32_t	tcpi_rcv_space;
268
269  uint32_t	tcpi_total_retrans;
270};
271
272
273/* For TCP_MD5SIG socket option.  */
274#define TCP_MD5SIG_MAXKEYLEN	80
275
276/* tcp_md5sig extension flags for TCP_MD5SIG_EXT.  */
277#define TCP_MD5SIG_FLAG_PREFIX	1 /* Address prefix length.  */
278#define TCP_MD5SIG_FLAG_IFINDEX	2 /* Ifindex set.  */
279
280struct tcp_md5sig
281{
282  struct sockaddr_storage tcpm_addr;		/* Address associated.  */
283  uint8_t	tcpm_flags;			/* Extension flags.  */
284  uint8_t	tcpm_prefixlen;			/* Address prefix.  */
285  uint16_t	tcpm_keylen;			/* Key length.  */
286  int		tcpm_ifindex;			/* Device index for scope.  */
287  uint8_t	tcpm_key[TCP_MD5SIG_MAXKEYLEN];	/* Key (binary).  */
288};
289
290/* For socket repair options.  */
291struct tcp_repair_opt
292{
293  uint32_t	opt_code;
294  uint32_t	opt_val;
295};
296
297/* Queue to repair, for TCP_REPAIR_QUEUE.  */
298enum
299{
300  TCP_NO_QUEUE,
301  TCP_RECV_QUEUE,
302  TCP_SEND_QUEUE,
303  TCP_QUEUES_NR,
304};
305
306/* For cookie transactions socket options.  */
307#define TCP_COOKIE_MIN		8		/*  64-bits */
308#define TCP_COOKIE_MAX		16		/* 128-bits */
309#define TCP_COOKIE_PAIR_SIZE	(2*TCP_COOKIE_MAX)
310
311/* Flags for both getsockopt and setsockopt */
312#define TCP_COOKIE_IN_ALWAYS	(1 << 0)	/* Discard SYN without cookie */
313#define TCP_COOKIE_OUT_NEVER	(1 << 1)	/* Prohibit outgoing cookies,
314						 * supersedes everything. */
315
316/* Flags for getsockopt */
317#define TCP_S_DATA_IN		(1 << 2)	/* Was data received? */
318#define TCP_S_DATA_OUT		(1 << 3)	/* Was data sent? */
319
320#define TCP_MSS_DEFAULT		 536U	/* IPv4 (RFC1122, RFC2581) */
321#define TCP_MSS_DESIRED		1220U	/* IPv6 (tunneled), EDNS0 (RFC3226) */
322
323struct tcp_cookie_transactions
324{
325  uint16_t	tcpct_flags;
326  uint8_t	__tcpct_pad1;
327  uint8_t	tcpct_cookie_desired;
328  uint16_t	tcpct_s_data_desired;
329  uint16_t	tcpct_used;
330  uint8_t	tcpct_value[TCP_MSS_DEFAULT];
331};
332
333/* For use with TCP_REPAIR_WINDOW.  */
334struct tcp_repair_window
335{
336  uint32_t snd_wl1;
337  uint32_t snd_wnd;
338  uint32_t max_window;
339  uint32_t rcv_wnd;
340  uint32_t rcv_wup;
341};
342
343/* For use with TCP_ZEROCOPY_RECEIVE.  */
344struct tcp_zerocopy_receive
345{
346  uint64_t address; /* In: address of mapping.  */
347  uint32_t length; /* In/out: number of bytes to map/mapped.  */
348  uint32_t recv_skip_hint; /* Out: amount of bytes to skip.  */
349};
350
351#endif /* Misc.  */
352
353#endif /* netinet/tcp.h */