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1c79356b 1/*
91447636 2 * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
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3 *
4 * @APPLE_LICENSE_HEADER_START@
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.
1c79356b 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.
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19 *
20 * @APPLE_LICENSE_HEADER_END@
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
107#define TCPOLEN_MAXSEG 4
108#define TCPOPT_WINDOW 3
109#define TCPOLEN_WINDOW 3
110#define TCPOPT_SACK_PERMITTED 4 /* Experimental */
111#define TCPOLEN_SACK_PERMITTED 2
112#define TCPOPT_SACK 5 /* Experimental */
113#define TCPOPT_TIMESTAMP 8
114#define TCPOLEN_TIMESTAMP 10
115#define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */
116#define TCPOPT_TSTAMP_HDR \
117 (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP)
118
119#define TCPOPT_CC 11 /* CC options: RFC-1644 */
120#define TCPOPT_CCNEW 12
121#define TCPOPT_CCECHO 13
122#define TCPOLEN_CC 6
123#define TCPOLEN_CC_APPA (TCPOLEN_CC+2)
124#define TCPOPT_CC_HDR(ccopt) \
125 (TCPOPT_NOP<<24|TCPOPT_NOP<<16|(ccopt)<<8|TCPOLEN_CC)
126
127/*
128 * Default maximum segment size for TCP.
4a249263 129 * With an IP MTU of 576, this is 536,
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130 * but 512 is probably more convenient.
131 * This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)).
132 */
133#define TCP_MSS 512
134
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135/*
136 * TCP_MINMSS is defined to be 216 which is fine for the smallest
137 * link MTU (256 bytes, SLIP interface) in the Internet.
138 * However it is very unlikely to come across such low MTU interfaces
139 * these days (anno dato 2004).
140 * Probably it can be set to 512 without ill effects. But we play safe.
141 * See tcp_subr.c tcp_minmss SYSCTL declaration for more comments.
142 * Setting this to "0" disables the minmss check.
143 */
144#define TCP_MINMSS 216
145
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146/*
147 * TCP_MINMSSOVERLOAD is defined to be 1000 which should cover any type
148 * of interactive TCP session.
149 * See tcp_subr.c tcp_minmssoverload SYSCTL declaration and tcp_input.c
150 * for more comments.
151 * Setting this to "0" disables the minmssoverload check.
152 */
153#define TCP_MINMSSOVERLOAD 1000
154
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155/*
156 * Default maximum segment size for TCP6.
157 * With an IP6 MSS of 1280, this is 1220,
158 * but 1024 is probably more convenient. (xxx kazu in doubt)
159 * This should be defined as MIN(1024, IP6_MSS - sizeof (struct tcpip6hdr))
160 */
161#define TCP6_MSS 1024
162
163#define TCP_MAXWIN 65535 /* largest value for (unscaled) window */
164#define TTCP_CLIENT_SND_WND 4096 /* dflt send window for T/TCP client */
165
166#define TCP_MAX_WINSHIFT 14 /* maximum window shift */
167
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168#define TCP_MAXBURST 4 /* maximum segments in a burst */
169
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170#define TCP_MAXHLEN (0xf<<2) /* max length of header in bytes */
171#define TCP_MAXOLEN (TCP_MAXHLEN - sizeof(struct tcphdr))
172 /* max space left for options */
91447636 173#endif /* _POSIX_C_SOURCE */
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174
175/*
176 * User-settable options (used with setsockopt).
177 */
178#define TCP_NODELAY 0x01 /* don't delay send to coalesce packets */
91447636 179#ifndef _POSIX_C_SOURCE
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180#define TCP_MAXSEG 0x02 /* set maximum segment size */
181#define TCP_NOPUSH 0x04 /* don't push last block of write */
182#define TCP_NOOPT 0x08 /* don't use TCP options */
55e303ae 183#define TCP_KEEPALIVE 0x10 /* idle time used when SO_KEEPALIVE is enabled */
91447636 184#endif /* _POSIX_C_SOURCE */
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185
186#endif