lib/common/genmask.c

	genmask.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * Copyright (C) 1993-2001 by Darren Reed.
 *
 * See the IPFILTER.LICENCE file for details on licencing.
 *
 * $Id: genmask.c,v 1.6 2002/01/28 06:50:46 darrenr Exp $
 */

#include "ipf.h"


int genmask(msk, mskp)
char *msk;
u_32_t *mskp;
{
    char *endptr = 0L;
    int bits;

    if (strchr(msk, '.') || strchr(msk, 'x') || strchr(msk, ':')) {
        /* possibly of the form xxx.xxx.xxx.xxx
         * or 0xYYYYYYYY */
#ifdef  USE_INET6
        if (use_inet6) {
            if (inet_pton(AF_INET6, msk, mskp) != 1)
                return -1;
        } else
#endif
        if (inet_aton(msk, (struct in_addr *)mskp) == 0)
            return -1;
    } else {
        /*
         * set x most significant bits
         */
        bits = (int)strtol(msk, &endptr, 0);
#ifdef  USE_INET6
        if ((*endptr != '\0') ||
            ((bits > 32) && !use_inet6) || (bits < 0) ||
            ((bits > 128) && use_inet6))
#else
        if (*endptr != '\0' || bits > 32 || bits < 0)
#endif
            return -1;
#ifdef  USE_INET6
        if (use_inet6)
            fill6bits(bits, mskp);
        else
#endif
        if (bits == 0)
            *mskp = 0;
        else
            *mskp = htonl(0xffffffff << (32 - bits));
    }
    return 0;
}