1 /* @(#) $Header: /tcpdump/master/tcpdump/tcp.h,v 1.11.2.1 2005/11/29 09:09:26 hannes Exp $ (LBL) */ 2 /* 3 * Copyright (c) 1982, 1986, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by the University of 17 * California, Berkeley and its contributors. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)tcp.h 8.1 (Berkeley) 6/10/93 35 */ 36 37 typedef u_int32_t tcp_seq; 38 /* 39 * TCP header. 40 * Per RFC 793, September, 1981. 41 */ 42 struct tcphdr { 43 u_int16_t th_sport; /* source port */ 44 u_int16_t th_dport; /* destination port */ 45 tcp_seq th_seq; /* sequence number */ 46 tcp_seq th_ack; /* acknowledgement number */ 47 u_int8_t th_offx2; /* data offset, rsvd */ 48 #define TH_OFF(th) (((th)->th_offx2 & 0xf0) >> 4) 49 u_int8_t th_flags; 50 #define TH_FIN 0x01 51 #define TH_SYN 0x02 52 #define TH_RST 0x04 53 #define TH_PUSH 0x08 54 #define TH_ACK 0x10 55 #define TH_URG 0x20 56 #define TH_ECNECHO 0x40 /* ECN Echo */ 57 #define TH_CWR 0x80 /* ECN Cwnd Reduced */ 58 u_int16_t th_win; /* window */ 59 u_int16_t th_sum; /* checksum */ 60 u_int16_t th_urp; /* urgent pointer */ 61 }; 62 63 #define TCPOPT_EOL 0 64 #define TCPOPT_NOP 1 65 #define TCPOPT_MAXSEG 2 66 #define TCPOLEN_MAXSEG 4 67 #define TCPOPT_WSCALE 3 /* window scale factor (rfc1323) */ 68 #define TCPOPT_SACKOK 4 /* selective ack ok (rfc2018) */ 69 #define TCPOPT_SACK 5 /* selective ack (rfc2018) */ 70 #define TCPOPT_ECHO 6 /* echo (rfc1072) */ 71 #define TCPOPT_ECHOREPLY 7 /* echo (rfc1072) */ 72 #define TCPOPT_TIMESTAMP 8 /* timestamp (rfc1323) */ 73 #define TCPOLEN_TIMESTAMP 10 74 #define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */ 75 #define TCPOPT_CC 11 /* T/TCP CC options (rfc1644) */ 76 #define TCPOPT_CCNEW 12 /* T/TCP CC options (rfc1644) */ 77 #define TCPOPT_CCECHO 13 /* T/TCP CC options (rfc1644) */ 78 #define TCPOPT_SIGNATURE 19 /* Keyed MD5 (rfc2385) */ 79 #define TCPOLEN_SIGNATURE 18 80 #define TCP_SIGLEN 16 /* length of an option 19 digest */ 81 #define TCPOPT_AUTH 20 /* Enhanced AUTH option */ 82 83 #define TCPOPT_TSTAMP_HDR \ 84 (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP) 85