xref: /titanic_41/usr/src/cmd/ipf/lib/common/tcpflags.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244) 
1 /*
2  * Copyright (C) 1993-2001 by Darren Reed.
3  *
4  * See the IPFILTER.LICENCE file for details on licencing.
5  *
6  * $Id: tcpflags.c,v 1.3 2002/11/02 07:18:01 darrenr Exp $
7  */
8 
9 #include "ipf.h"
10 
11 
12 /*
13  * ECN is a new addition to TCP - RFC 2481
14  */
15 #ifndef TH_ECN
16 # define	TH_ECN  0x40
17 #endif
18 #ifndef TH_CWR
19 # define	TH_CWR  0x80
20 #endif
21 
22 extern	char	flagset[];
23 extern	u_char	flags[];
24 
25 
tcpflags(flgs)26 u_char tcpflags(flgs)
27 char *flgs;
28 {
29 	u_char tcpf = 0;
30 	char *s, *t;
31 
32 	for (s = flgs; *s; s++) {
33 		if (*s == 'W')
34 			tcpf |= TH_CWR;
35 		else {
36 			if (!(t = strchr(flagset, *s))) {
37 				return 0;
38 			}
39 			tcpf |= flags[t - flagset];
40 		}
41 	}
42 	return tcpf;
43 }
44