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1c79356b 1/*
5d5c5d0d
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2 * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
3 *
6601e61a 4 * @APPLE_LICENSE_HEADER_START@
1c79356b 5 *
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6 * The contents of this file constitute Original Code as defined in and
7 * are subject to the Apple Public Source License Version 1.1 (the
8 * "License"). You may not use this file except in compliance with the
9 * License. Please obtain a copy of the License at
10 * http://www.apple.com/publicsource and read it before using this file.
8f6c56a5 11 *
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12 * This Original Code and all software distributed under the License are
13 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
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14 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
15 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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16 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
17 * License for the specific language governing rights and limitations
18 * under the License.
8f6c56a5 19 *
6601e61a 20 * @APPLE_LICENSE_HEADER_END@
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21 */
22/*
23 * Copyright (c) 1982, 1986, 1993
24 * The Regents of the University of California. All rights reserved.
25 *
26 * Redistribution and use in source and binary forms, with or without
27 * modification, are permitted provided that the following conditions
28 * are met:
29 * 1. Redistributions of source code must retain the above copyright
30 * notice, this list of conditions and the following disclaimer.
31 * 2. Redistributions in binary form must reproduce the above copyright
32 * notice, this list of conditions and the following disclaimer in the
33 * documentation and/or other materials provided with the distribution.
34 * 3. All advertising materials mentioning features or use of this software
35 * must display the following acknowledgement:
36 * This product includes software developed by the University of
37 * California, Berkeley and its contributors.
38 * 4. Neither the name of the University nor the names of its contributors
39 * may be used to endorse or promote products derived from this software
40 * without specific prior written permission.
41 *
42 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
43 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
44 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
45 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
46 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
47 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
48 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
49 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
50 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
51 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52 * SUCH DAMAGE.
53 *
54 * @(#)tcp.h 8.1 (Berkeley) 6/10/93
9bccf70c 55 * $FreeBSD: src/sys/netinet/tcp.h,v 1.13.2.3 2001/03/01 22:08:42 jlemon Exp $
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56 */
57
58#ifndef _NETINET_TCP_H_
59#define _NETINET_TCP_H_
9bccf70c 60#include <sys/appleapiopts.h>
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61#include <sys/_types.h>
62#include <machine/endian.h>
1c79356b 63
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64#ifndef _POSIX_C_SOURCE
65typedef __uint32_t tcp_seq;
66typedef __uint32_t tcp_cc; /* connection count per rfc1644 */
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67
68#define tcp6_seq tcp_seq /* for KAME src sync over BSD*'s */
69#define tcp6hdr tcphdr /* for KAME src sync over BSD*'s */
70
71/*
72 * TCP header.
73 * Per RFC 793, September, 1981.
74 */
75struct tcphdr {
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76 unsigned short th_sport; /* source port */
77 unsigned short th_dport; /* destination port */
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78 tcp_seq th_seq; /* sequence number */
79 tcp_seq th_ack; /* acknowledgement number */
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80#if __DARWIN_BYTE_ORDER == __DARWIN_LITTLE_ENDIAN
81 unsigned int th_x2:4, /* (unused) */
82 th_off:4; /* data offset */
1c79356b 83#endif
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84#if __DARWIN_BYTE_ORDER == __DARWIN_BIG_ENDIAN
85 unsigned int th_off:4, /* data offset */
86 th_x2:4; /* (unused) */
1c79356b 87#endif
91447636 88 unsigned char th_flags;
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89#define TH_FIN 0x01
90#define TH_SYN 0x02
91#define TH_RST 0x04
92#define TH_PUSH 0x08
93#define TH_ACK 0x10
94#define TH_URG 0x20
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95#define TH_ECE 0x40
96#define TH_CWR 0x80
97#define TH_FLAGS (TH_FIN|TH_SYN|TH_RST|TH_ACK|TH_URG|TH_ECE|TH_CWR)
1c79356b 98
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99 unsigned short th_win; /* window */
100 unsigned short th_sum; /* checksum */
101 unsigned short th_urp; /* urgent pointer */
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102};
103
104#define TCPOPT_EOL 0
105#define TCPOPT_NOP 1
106#define TCPOPT_MAXSEG 2
8ad349bb 107#define TCPOLEN_MAXSEG 4
1c79356b 108#define TCPOPT_WINDOW 3
8ad349bb 109#define TCPOLEN_WINDOW 3
1c79356b 110#define TCPOPT_SACK_PERMITTED 4 /* Experimental */
6601e61a 111#define TCPOLEN_SACK_PERMITTED 2
1c79356b 112#define TCPOPT_SACK 5 /* Experimental */
8ad349bb 113#define TCPOLEN_SACK 8 /* len of sack block */
1c79356b 114#define TCPOPT_TIMESTAMP 8
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115#define TCPOLEN_TIMESTAMP 10
116#define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */
117#define TCPOPT_TSTAMP_HDR \
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118 (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP)
119
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120#define MAX_TCPOPTLEN 40 /* Absolute maximum TCP options len */
121
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122#define TCPOPT_CC 11 /* CC options: RFC-1644 */
123#define TCPOPT_CCNEW 12
124#define TCPOPT_CCECHO 13
125#define TCPOLEN_CC 6
126#define TCPOLEN_CC_APPA (TCPOLEN_CC+2)
127#define TCPOPT_CC_HDR(ccopt) \
128 (TCPOPT_NOP<<24|TCPOPT_NOP<<16|(ccopt)<<8|TCPOLEN_CC)
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129#define TCPOPT_SIGNATURE 19 /* Keyed MD5: RFC 2385 */
130#define TCPOLEN_SIGNATURE 18
131
132/* Option definitions */
133#define TCPOPT_SACK_PERMIT_HDR \
134(TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_SACK_PERMITTED<<8|TCPOLEN_SACK_PERMITTED)
135#define TCPOPT_SACK_HDR (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_SACK<<8)
136/* Miscellaneous constants */
137#define MAX_SACK_BLKS 6 /* Max # SACK blocks stored at sender side */
138#define TCP_MAX_SACK 3 /* MAX # SACKs sent in any segment */
139
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140
141/*
142 * Default maximum segment size for TCP.
4a249263 143 * With an IP MTU of 576, this is 536,
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144 * but 512 is probably more convenient.
145 * This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)).
146 */
147#define TCP_MSS 512
148
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149/*
150 * TCP_MINMSS is defined to be 216 which is fine for the smallest
151 * link MTU (256 bytes, SLIP interface) in the Internet.
152 * However it is very unlikely to come across such low MTU interfaces
153 * these days (anno dato 2004).
154 * Probably it can be set to 512 without ill effects. But we play safe.
155 * See tcp_subr.c tcp_minmss SYSCTL declaration for more comments.
156 * Setting this to "0" disables the minmss check.
157 */
158#define TCP_MINMSS 216
159
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160/*
161 * TCP_MINMSSOVERLOAD is defined to be 1000 which should cover any type
162 * of interactive TCP session.
163 * See tcp_subr.c tcp_minmssoverload SYSCTL declaration and tcp_input.c
164 * for more comments.
165 * Setting this to "0" disables the minmssoverload check.
166 */
167#define TCP_MINMSSOVERLOAD 1000
168
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169/*
170 * Default maximum segment size for TCP6.
171 * With an IP6 MSS of 1280, this is 1220,
172 * but 1024 is probably more convenient. (xxx kazu in doubt)
173 * This should be defined as MIN(1024, IP6_MSS - sizeof (struct tcpip6hdr))
174 */
175#define TCP6_MSS 1024
176
177#define TCP_MAXWIN 65535 /* largest value for (unscaled) window */
178#define TTCP_CLIENT_SND_WND 4096 /* dflt send window for T/TCP client */
179
180#define TCP_MAX_WINSHIFT 14 /* maximum window shift */
181
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182#define TCP_MAXBURST 4 /* maximum segments in a burst */
183
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184#define TCP_MAXHLEN (0xf<<2) /* max length of header in bytes */
185#define TCP_MAXOLEN (TCP_MAXHLEN - sizeof(struct tcphdr))
186 /* max space left for options */
91447636 187#endif /* _POSIX_C_SOURCE */
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188
189/*
190 * User-settable options (used with setsockopt).
191 */
192#define TCP_NODELAY 0x01 /* don't delay send to coalesce packets */
91447636 193#ifndef _POSIX_C_SOURCE
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194#define TCP_MAXSEG 0x02 /* set maximum segment size */
195#define TCP_NOPUSH 0x04 /* don't push last block of write */
196#define TCP_NOOPT 0x08 /* don't use TCP options */
55e303ae 197#define TCP_KEEPALIVE 0x10 /* idle time used when SO_KEEPALIVE is enabled */
6601e61a 198
91447636 199#endif /* _POSIX_C_SOURCE */
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200
201#endif