tcp.h revision 6247
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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)tcp.h 8.1 (Berkeley) 6/10/93 34 * $Id: tcp.h,v 1.3 1994/08/21 05:27:34 paul Exp $ 35 */ 36 37#ifndef _NETINET_TCP_H_ 38#define _NETINET_TCP_H_ 39 40typedef u_long tcp_seq; 41#ifdef TTCP 42typedef u_long tcp_cc; /* connection count per rfc1644 */ 43#endif 44 45/* 46 * TCP header. 47 * Per RFC 793, September, 1981. 48 */ 49struct tcphdr { 50 u_short th_sport; /* source port */ 51 u_short th_dport; /* destination port */ 52 tcp_seq th_seq; /* sequence number */ 53 tcp_seq th_ack; /* acknowledgement number */ 54#if BYTE_ORDER == LITTLE_ENDIAN 55 u_char th_x2:4, /* (unused) */ 56 th_off:4; /* data offset */ 57#endif 58#if BYTE_ORDER == BIG_ENDIAN 59 u_char th_off:4, /* data offset */ 60 th_x2:4; /* (unused) */ 61#endif 62 u_char th_flags; 63#define TH_FIN 0x01 64#define TH_SYN 0x02 65#define TH_RST 0x04 66#define TH_PUSH 0x08 67#define TH_ACK 0x10 68#define TH_URG 0x20 69#ifdef TTCP 70#define TH_FLAGS (TH_FIN|TH_SYN|TH_RST|TH_ACK|TH_URG) 71#endif 72 u_short th_win; /* window */ 73 u_short th_sum; /* checksum */ 74 u_short th_urp; /* urgent pointer */ 75}; 76 77#define TCPOPT_EOL 0 78#define TCPOPT_NOP 1 79#define TCPOPT_MAXSEG 2 80#define TCPOLEN_MAXSEG 4 81#define TCPOPT_WINDOW 3 82#define TCPOLEN_WINDOW 3 83#define TCPOPT_SACK_PERMITTED 4 /* Experimental */ 84#define TCPOLEN_SACK_PERMITTED 2 85#define TCPOPT_SACK 5 /* Experimental */ 86#define TCPOPT_TIMESTAMP 8 87#define TCPOLEN_TIMESTAMP 10 88#define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */ 89#define TCPOPT_TSTAMP_HDR \ 90 (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP) 91 92#ifdef TTCP 93#define TCPOPT_CC 11 /* CC options: RFC-1644 */ 94#define TCPOPT_CCNEW 12 95#define TCPOPT_CCECHO 13 96#define TCPOLEN_CC 6 97#define TCPOLEN_CC_APPA (TCPOLEN_CC+2) 98#define TCPOPT_CC_HDR(ccopt) \ 99 (TCPOPT_NOP<<24|TCPOPT_NOP<<16|(ccopt)<<8|TCPOLEN_CC) 100#endif 101 102/* 103 * Default maximum segment size for TCP. 104 * With an IP MSS of 576, this is 536, 105 * but 512 is probably more convenient. 106 * This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)). 107 */ 108#define TCP_MSS 512 109 110#define TCP_MAXWIN 65535 /* largest value for (unscaled) window */ 111#ifdef TTCP 112#define TTCP_CLIENT_SND_WND 4096 /* dflt send window for T/TCP client */ 113#endif 114 115#define TCP_MAX_WINSHIFT 14 /* maximum window shift */ 116 117#define TCP_MAXHLEN (0xf<<2) /* max length of header in bytes */ 118#define TCP_MAXOLEN (TCP_MAXHLEN - sizeof(struct tcphdr)) 119 /* max space left for options */ 120 121/* 122 * User-settable options (used with setsockopt). 123 */ 124#define TCP_NODELAY 0x01 /* don't delay send to coalesce packets */ 125#define TCP_MAXSEG 0x02 /* set maximum segment size */ 126#ifdef TTCP 127#define TCP_NOPUSH 0x04 /* don't push last block of write */ 128#define TCP_NOOPT 0x08 /* don't use TCP options */ 129#endif 130 131#endif 132