lib/common/ntomask.c

	ntomask.c revision 7663b81667fda05833f609eceac713f0a83c2347
/*
 * Copyright (C) 2002 by Darren Reed.
 *
 * See the IPFILTER.LICENCE file for details on licencing.
 *
 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include "ipf.h"

int ntomask(v, nbits, ap)
int v, nbits;
u_32_t *ap;
{
    u_32_t mask;

    if (nbits < 0)
        return -1;

    switch (v)
    {
    case 4 :
        if (nbits > 32 || use_inet6 != 0)
            return -1;
        if (nbits == 0) {
            mask = 0;
        } else {
            mask = 0xffffffff;
            mask <<= (32 - nbits);
        }
        *ap = htonl(mask);
        break;

    case 6 :
        if (nbits > 128)
            return -1;
        fill6bits(nbits, ap);
        break;

    default :
        return -1;
    }
    return 0;
}