CIDR 2

<?php

class Cidr {



    /** ***********************************/
    /** Usable part ***********************/
    /*** **********************************/

    public function isIpValid($ip){
        return filter_var($ip, FILTER_VALIDATE_IP);
    }

    public function isInOprRange($opr_range, $ip){
        if ( strpos($opr_range,';') !== false ) {
            $ips = explode(';', $opr_range);
            foreach ( $ips as $ip_range ) {
                if ( strpos($ip_range,'-') !== false ) {
                    list($inicial, $final) = explode('-', $ip_range);
                    if ( $this->simpleInRange($ip, $inicial, $final) ) {
                        return true;
                    }
                } else {
                    if ( $ip == $ip_range ) {
                        return true;
                    }
                }
            }
        }
        return $opr_range == $ip;
    }

    public function simpleInRange($ip, $initial, $final){
        $initial = ip2long($initial);
        $final = ip2long($final);
        $ip = ip2long($ip);

        return ($ip >= $initial && $ip <= $final);
    }

    /** ***********************************/
    /** End of usable part ****************/
    /*** **********************************/

    public function getCidrByFirstLastIP($first, $last){
        $first = ip2long($first);
        $last = ip2long($last);
        $qtd = (($last - $first)+2);
        $q = 0;
        while($qtd/2 > 1) {
            $q++;
            $qtd = $qtd/2;
        }
        return 32-($q+1);

    }

    public function getTotalIPsFromCidr($cidr) {
        return 1 << (32 - $cidr);
    }

    public function getFirstUsableIP($ip, $cidr){
        return long2ip(ip2long($this->getNetworkAddress($ip, $cidr)) + 1);
    }

    public function getLastUsableIP($ip, $cidr) {
        return long2ip(ip2long($this->getFirstUsableIP($ip, $cidr)) + (1 << (32 - $cidr)) -2);
    }

    public function isIPInRange($range, $cidr, $ip){
        // Calculando o range
        $initial = ip2long($this->getFirstUsableIP($range, $cidr));
        $final = ip2long($this->getLastUsableIP($range, $cidr));
        $ip = ip2long($ip);

        return ($ip >= $initial && $ip <= $final);
    }

    public function getNetmaskByCidr($cidr){
        $bin = '';
        for ( $i=1; $i<=32; $i++ ) {
            $bin .= ($cidr >= $i) ? '1' : '0';
        }
        $netmask = long2ip(bindec($bin));
        if ($netmask == '0.0.0.0') return false;
        return $netmask;
    }

    public function getCidrByNetmask($netmask){
        $bits = 0;
        $netmask = explode('.', $netmask);
        foreach ($netmask as $oct) {
            $bits += strlen(str_replace('0', '', decbin($oct)));
        }
        return $bits;
    }

    public function getNetworkAddress($ip, $cidr){
        return long2ip((ip2long($ip)) & ((-1 << (32 - (int)$cidr))));
    }
}
?>