1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * Definitions for the TCP protocol.
7 *
8 * Version: @(#)tcp.h 1.0.2 04/28/93
9 *
10 * Author: Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
16 */
17 #ifndef _LINUX_TCP_H
18 #define _LINUX_TCP_H
19
20
21 #define HEADER_SIZE 64 /* maximum header size */
22
23
24 struct tcphdr {
25 unsigned short source;
26 unsigned short dest;
27 unsigned long seq;
28 unsigned long ack_seq;
29 unsigned short res1:4,
30 doff:4,
31 fin:1,
32 syn:1,
33 rst:1,
34 psh:1,
35 ack:1,
36 urg:1,
37 res2:2;
38 unsigned short window;
39 unsigned short check;
40 unsigned short urg_ptr;
41 };
42
43
44 enum {
45 TCP_ESTABLISHED = 1,
46 TCP_SYN_SENT,
47 TCP_SYN_RECV,
48 #if 0
49 TCP_CLOSING, /* not a valid state, just a seperator so we can use
50 < tcp_closing or > tcp_closing for checks. */
51 #endif
52 TCP_FIN_WAIT1,
53 TCP_FIN_WAIT2,
54 TCP_TIME_WAIT,
55 TCP_CLOSE,
56 TCP_CLOSE_WAIT,
57 TCP_LAST_ACK,
58 TCP_LISTEN
59 };
60
61 #endif /* _LINUX_TCP_H */