libefivar: Remove unused PACKAGE from Makefile.
[dragonfly.git] / sys / netinet / tcp.h
blob1eacd0f81db48ccb0bc2f73fcc593895afb4f07d
1 /*
2 * Copyright (c) 1982, 1986, 1993
3 * The Regents of the University of California. All rights reserved.
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 * 3. 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.
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.
29 * @(#)tcp.h 8.1 (Berkeley) 6/10/93
30 * $FreeBSD: src/sys/netinet/tcp.h,v 1.13.2.3 2001/03/01 22:08:42 jlemon Exp $
33 #ifndef _NETINET_TCP_H_
34 #define _NETINET_TCP_H_
36 #include <sys/cdefs.h>
38 #if __BSD_VISIBLE
40 #include <sys/types.h>
42 typedef u_int32_t tcp_seq;
43 typedef int32_t tcp_seq_diff_t;
45 #define tcp6_seq tcp_seq /* for KAME src sync over BSD*'s */
46 #define tcp6hdr tcphdr /* for KAME src sync over BSD*'s */
49 * TCP header.
50 * Per RFC 793, September, 1981.
52 struct tcphdr {
53 u_short th_sport; /* source port */
54 u_short th_dport; /* destination port */
55 tcp_seq th_seq; /* sequence number */
56 tcp_seq th_ack; /* acknowledgement number */
57 #if _BYTE_ORDER == _LITTLE_ENDIAN
58 u_int th_x2:4, /* (unused) */
59 th_off:4; /* data offset */
60 #elif _BYTE_ORDER == _BIG_ENDIAN
61 u_int th_off:4, /* data offset */
62 th_x2:4; /* (unused) */
63 #else
64 #error "Byte order not implemented"
65 #endif
66 u_char th_flags;
67 #define TH_FIN 0x01
68 #define TH_SYN 0x02
69 #define TH_RST 0x04
70 #define TH_PUSH 0x08
71 #define TH_ACK 0x10
72 #define TH_URG 0x20
73 #define TH_ECE 0x40
74 #define TH_CWR 0x80
75 #define TH_FLAGS (TH_FIN|TH_SYN|TH_RST|TH_ACK|TH_URG|TH_ECE|TH_CWR)
77 u_short th_win; /* window */
78 u_short th_sum; /* checksum */
79 u_short th_urp; /* urgent pointer */
82 #define TCPOPT_EOL 0
83 #define TCPOPT_NOP 1
84 #define TCPOPT_2NOPs (TCPOPT_NOP << 24 | TCPOPT_NOP << 16)
85 #define TCPOPT_MAXSEG 2
86 #define TCPOLEN_MAXSEG 4
87 #define TCPOPT_WINDOW 3
88 #define TCPOLEN_WINDOW 3
89 #define TCPOPT_SACK_PERMITTED 4
90 #define TCPOLEN_SACK_PERMITTED 2
91 #define TCPOPT_SACK_PERMITTED_ALIGNED \
92 (TCPOPT_2NOPs | TCPOPT_SACK_PERMITTED << 8 | TCPOLEN_SACK_PERMITTED)
93 #define TCPOLEN_SACK_PERMITTED_ALIGNED 4
94 #define TCPOPT_SACK 5
95 #define TCPOLEN_SACK 2
96 #define TCPOLEN_SACK_BLOCK 8
97 #define TCPOPT_SACK_ALIGNED (TCPOPT_2NOPs | TCPOPT_SACK << 8)
98 #define TCPOLEN_SACK_ALIGNED 4
99 #define TCPOPT_TIMESTAMP 8
100 #define TCPOLEN_TIMESTAMP 10
101 #define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */
102 #define TCPOPT_TSTAMP_HDR \
103 (TCPOPT_2NOPs | TCPOPT_TIMESTAMP << 8 | TCPOLEN_TIMESTAMP)
104 #define TCPOPT_CC 11 /* CC options: RFC-1644 */
105 #define TCPOPT_CCNEW 12
106 #define TCPOPT_CCECHO 13
107 #define TCPOPT_SIGNATURE 19 /* Keyed MD5: RFC 2385 */
108 #define TCPOLEN_SIGNATURE 18
111 * Default maximum segment size for TCP.
112 * With an IP MSS of 576, this is 536,
113 * but 512 is probably more convenient.
114 * This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)).
116 #define TCP_MSS 512
119 * TCP_MINMSS is defined to be 256 which is fine for the smallest
120 * link MTU (296 bytes, SLIP interface) in the Internet.
121 * However it is very unlikely to come across such low MTU interfaces
122 * these days (anno dato 2003).
123 * Probably it can be set to 512 without ill effects. But we play safe.
124 * See tcp_subr.c tcp_minmss SYSCTL declaration for more comments.
125 * Setting this to "0" disables the minmss check.
127 #define TCP_MINMSS 256
130 * Default maximum segment size for TCP6.
131 * With an IP6 MSS of 1280, this is 1220,
132 * but 1024 is probably more convenient. (xxx kazu in doubt)
133 * This should be defined as MIN(1024, IP6_MSS - sizeof (struct tcpip6hdr))
135 * NOTE: TCP_MIN_WINSHIFT is used when negotiating window scaling. Larger
136 * values are possible but apparently some firewires blows up if
137 * values larger then 5 are used, so use 5.
139 #define TCP6_MSS 1024
141 #define TCP_MAXWIN 65535 /* max value for (unscaled) window */
143 #define TCP_MIN_WINSHIFT 5 /* requested minimum (x32) */
144 #define TCP_MAX_WINSHIFT 14 /* maximum window shift */
146 #define TCP_MAXBURST 4 /* maximum segments in a burst */
148 #define TCP_MAXHLEN (0xf<<2) /* max length of header in bytes */
149 #define TCP_MAXOLEN (TCP_MAXHLEN - sizeof(struct tcphdr))
150 /* max space left for options */
151 #endif /* __BSD_VISIBLE */
154 * User-settable options (used with setsockopt).
156 #define TCP_NODELAY 0x01 /* don't delay send to coalesce packets */
157 #if __BSD_VISIBLE
158 #define TCP_MAXSEG 0x02 /* set maximum segment size */
159 #define TCP_NOPUSH 0x04 /* don't push last block of write */
160 #define TCP_NOOPT 0x08 /* don't use TCP options */
161 #define TCP_SIGNATURE_ENABLE 0x10 /* use MD5 digests (RFC2385) */
162 #define TCP_KEEPINIT 0x20 /* set max time to establish connection */
163 /* 0x40 unused */
164 #define TCP_FASTKEEP 0x80
165 #define TCP_KEEPIDLE 0x100 /* set time before keepalive probes begin */
166 #define TCP_KEEPINTVL 0x200 /* set time between keepalive probes */
167 #define TCP_KEEPCNT 0x400 /* set max number of keepalive probes */
168 #endif /* __BSD_VISIBLE */
170 #endif