tcp.h revision 1541
11541Srgrimes/* 21541Srgrimes * Copyright (c) 1982, 1986, 1993 31541Srgrimes * The Regents of the University of California. All rights reserved. 41541Srgrimes * 51541Srgrimes * Redistribution and use in source and binary forms, with or without 61541Srgrimes * modification, are permitted provided that the following conditions 71541Srgrimes * are met: 81541Srgrimes * 1. Redistributions of source code must retain the above copyright 91541Srgrimes * notice, this list of conditions and the following disclaimer. 101541Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 111541Srgrimes * notice, this list of conditions and the following disclaimer in the 121541Srgrimes * documentation and/or other materials provided with the distribution. 131541Srgrimes * 3. All advertising materials mentioning features or use of this software 141541Srgrimes * must display the following acknowledgement: 151541Srgrimes * This product includes software developed by the University of 161541Srgrimes * California, Berkeley and its contributors. 171541Srgrimes * 4. Neither the name of the University nor the names of its contributors 181541Srgrimes * may be used to endorse or promote products derived from this software 191541Srgrimes * without specific prior written permission. 201541Srgrimes * 211541Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 221541Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 231541Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 241541Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 251541Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 261541Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 271541Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 281541Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 291541Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 301541Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 311541Srgrimes * SUCH DAMAGE. 321541Srgrimes * 331541Srgrimes * @(#)tcp.h 8.1 (Berkeley) 6/10/93 341541Srgrimes */ 351541Srgrimes 361541Srgrimestypedef u_long tcp_seq; 371541Srgrimes/* 381541Srgrimes * TCP header. 391541Srgrimes * Per RFC 793, September, 1981. 401541Srgrimes */ 411541Srgrimesstruct tcphdr { 421541Srgrimes u_short th_sport; /* source port */ 431541Srgrimes u_short th_dport; /* destination port */ 441541Srgrimes tcp_seq th_seq; /* sequence number */ 451541Srgrimes tcp_seq th_ack; /* acknowledgement number */ 461541Srgrimes#if BYTE_ORDER == LITTLE_ENDIAN 471541Srgrimes u_char th_x2:4, /* (unused) */ 481541Srgrimes th_off:4; /* data offset */ 491541Srgrimes#endif 501541Srgrimes#if BYTE_ORDER == BIG_ENDIAN 511541Srgrimes u_char th_off:4, /* data offset */ 521541Srgrimes th_x2:4; /* (unused) */ 531541Srgrimes#endif 541541Srgrimes u_char th_flags; 551541Srgrimes#define TH_FIN 0x01 561541Srgrimes#define TH_SYN 0x02 571541Srgrimes#define TH_RST 0x04 581541Srgrimes#define TH_PUSH 0x08 591541Srgrimes#define TH_ACK 0x10 601541Srgrimes#define TH_URG 0x20 611541Srgrimes u_short th_win; /* window */ 621541Srgrimes u_short th_sum; /* checksum */ 631541Srgrimes u_short th_urp; /* urgent pointer */ 641541Srgrimes}; 651541Srgrimes 661541Srgrimes#define TCPOPT_EOL 0 671541Srgrimes#define TCPOPT_NOP 1 681541Srgrimes#define TCPOPT_MAXSEG 2 691541Srgrimes#define TCPOLEN_MAXSEG 4 701541Srgrimes#define TCPOPT_WINDOW 3 711541Srgrimes#define TCPOLEN_WINDOW 3 721541Srgrimes#define TCPOPT_SACK_PERMITTED 4 /* Experimental */ 731541Srgrimes#define TCPOLEN_SACK_PERMITTED 2 741541Srgrimes#define TCPOPT_SACK 5 /* Experimental */ 751541Srgrimes#define TCPOPT_TIMESTAMP 8 761541Srgrimes#define TCPOLEN_TIMESTAMP 10 771541Srgrimes#define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */ 781541Srgrimes 791541Srgrimes#define TCPOPT_TSTAMP_HDR \ 801541Srgrimes (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP) 811541Srgrimes 821541Srgrimes/* 831541Srgrimes * Default maximum segment size for TCP. 841541Srgrimes * With an IP MSS of 576, this is 536, 851541Srgrimes * but 512 is probably more convenient. 861541Srgrimes * This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)). 871541Srgrimes */ 881541Srgrimes#define TCP_MSS 512 891541Srgrimes 901541Srgrimes#define TCP_MAXWIN 65535 /* largest value for (unscaled) window */ 911541Srgrimes 921541Srgrimes#define TCP_MAX_WINSHIFT 14 /* maximum window shift */ 931541Srgrimes 941541Srgrimes/* 951541Srgrimes * User-settable options (used with setsockopt). 961541Srgrimes */ 971541Srgrimes#define TCP_NODELAY 0x01 /* don't delay send to coalesce packets */ 981541Srgrimes#define TCP_MAXSEG 0x02 /* set maximum segment size */ 99