xref: /onnv-gate/usr/src/cmd/ipf/lib/common/tcpflags.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * Copyright (C) 1993-2001 by Darren Reed.
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * See the IPFILTER.LICENCE file for details on licencing.
5*0Sstevel@tonic-gate  *
6*0Sstevel@tonic-gate  * $Id: tcpflags.c,v 1.3 2002/11/02 07:18:01 darrenr Exp $
7*0Sstevel@tonic-gate  */
8*0Sstevel@tonic-gate 
9*0Sstevel@tonic-gate #include "ipf.h"
10*0Sstevel@tonic-gate 
11*0Sstevel@tonic-gate 
12*0Sstevel@tonic-gate /*
13*0Sstevel@tonic-gate  * ECN is a new addition to TCP - RFC 2481
14*0Sstevel@tonic-gate  */
15*0Sstevel@tonic-gate #ifndef TH_ECN
16*0Sstevel@tonic-gate # define	TH_ECN  0x40
17*0Sstevel@tonic-gate #endif
18*0Sstevel@tonic-gate #ifndef TH_CWR
19*0Sstevel@tonic-gate # define	TH_CWR  0x80
20*0Sstevel@tonic-gate #endif
21*0Sstevel@tonic-gate 
22*0Sstevel@tonic-gate extern	char	flagset[];
23*0Sstevel@tonic-gate extern	u_char	flags[];
24*0Sstevel@tonic-gate 
25*0Sstevel@tonic-gate 
tcpflags(flgs)26*0Sstevel@tonic-gate u_char tcpflags(flgs)
27*0Sstevel@tonic-gate char *flgs;
28*0Sstevel@tonic-gate {
29*0Sstevel@tonic-gate 	u_char tcpf = 0;
30*0Sstevel@tonic-gate 	char *s, *t;
31*0Sstevel@tonic-gate 
32*0Sstevel@tonic-gate 	for (s = flgs; *s; s++) {
33*0Sstevel@tonic-gate 		if (*s == 'W')
34*0Sstevel@tonic-gate 			tcpf |= TH_CWR;
35*0Sstevel@tonic-gate 		else {
36*0Sstevel@tonic-gate 			if (!(t = strchr(flagset, *s))) {
37*0Sstevel@tonic-gate 				return 0;
38*0Sstevel@tonic-gate 			}
39*0Sstevel@tonic-gate 			tcpf |= flags[t - flagset];
40*0Sstevel@tonic-gate 		}
41*0Sstevel@tonic-gate 	}
42*0Sstevel@tonic-gate 	return tcpf;
43*0Sstevel@tonic-gate }
44