1 /* @(#) $Header: /home/pdw/vcvs/repos/iftop/tcp.h,v 1.2 2003/06/06 22:42:35 pdw 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 
79 #define TCPOPT_TSTAMP_HDR	\
80     (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP)
81