xref: /freebsd/sbin/ipf/libipf/nat_setgroupmap.c (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
1 
2 /*
3  * Copyright (C) 2012 by Darren Reed.
4  *
5  * See the IPFILTER.LICENCE file for details on licencing.
6  */
7 #if !defined(lint)
8 static const char rcsid[] = "@(#)$Id$";
9 #endif
10 
11 #include "ipf.h"
12 
13 void
14 nat_setgroupmap(ipnat_t *n)
15 {
16 	if (n->in_nsrcmsk == n->in_osrcmsk)
17 		n->in_ippip = 1;
18 	else if (n->in_flags & IPN_AUTOPORTMAP) {
19 		n->in_ippip = ~ntohl(n->in_osrcmsk);
20 		if (n->in_nsrcmsk != 0xffffffff)
21 			n->in_ippip /= (~ntohl(n->in_nsrcmsk) + 1);
22 		n->in_ippip++;
23 		if (n->in_ippip == 0)
24 			n->in_ippip = 1;
25 		n->in_ppip = USABLE_PORTS / n->in_ippip;
26 	} else {
27 		n->in_space = USABLE_PORTS * ~ntohl(n->in_nsrcmsk);
28 		n->in_snip = 0;
29 		if (!(n->in_ppip = n->in_spmin))
30 			n->in_ppip = 1;
31 		n->in_ippip = USABLE_PORTS / n->in_ppip;
32 	}
33 }
34