l<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category  ZendX
 * @package   ZendX_Whois
 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
 * @license   http://framework.zend.com/license/new-bsd     New BSD License
 * @version   $Id$
 */

/**
 * @see ZendX_Whois_Adapter_Base
 */
require_once 'ZendX/Whois/Adapter/Base.php';

/**
 * Cidr adapter for whois
 *
 * @category  ZendX
 * @package   ZendX_Whois
 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
 * @license   http://framework.zend.com/license/new-bsd     New BSD License
 */
class ZendX_Whois_Adapter_Cidr extends ZendX_Whois_Adapter_Base 
{
    /**
     * Defined by ZendX_Whois_Adapter_Base
     *
     * @return string
     */
    public function getName()
    {
        return 'cidr';
    }
    
    /**
     * Defined by ZendX_Whois_Adapter_Base
     *
     * @param  string $host
     * @return boolean
     */
    public function isUsable($host)
    {
        return (preg_match('#([0-9]+\.)+[0-9]+#', $host) === 1);
    }
    
    /**
     * Defined by ZendX_Whois_Adapter_Base
     *
     * @param  string $host
     * @return array|null
     */
    protected function _getWhoisServer($host)
    {
        foreach ($this->_definitions as $cidr => $server) {
            if ($this->_cidrMatch($cidr, $host)) {
                return $server;
            }
        }
        
        return $this->_defaultServer;
    }
    
    /**
     * Defined by ZendX_Whois_Adapter_Base
     *
     * @return string
     */
    protected function _getDefaultDefinitionFile()
    {
        return (dirname(dirname(__FILE__)) . '/Definitions/Adapters/Cidr.xml');
    }
    
    /**
     * Check an IP adress against a CIDR
     *
     * @param string $cidr
     * @param string $ip
     * @return boolean
     */
    protected function _cidrMatch($cidr, $ip)
    {
        // Get the base and the bits from the CIDR
        list($base, $bits) = explode('/', $cidr);

        // Now split it up into it's classes
        list($a, $b, $c, $d) = explode('.', $base);

        // Now do some bit shifting/switching to convert to ints
        $i    = ($a << 24) + ($b << 16) + ($c << 8) + $d;
        $mask = $bits == 0 ? 0: (~0 << (32 - $bits));

        // Here's our lowest int
        $low = $i & $mask;

        // Here's our highest int
        $high = $i | (~$mask & 0xFFFFFFFF);

        // Now split the ip we're checking against up into classes
        list($a, $b, $c, $d) = explode('.', $ip);

        // Now convert the ip we're checking against to an int
        $check = ($a << 24) + ($b << 16) + ($c << 8) + $d;

        // If the ip is within the range, including highest/lowest values,
        // then it's witin the CIDR range
        if ($check >= $low && $check <= $high) {
            return true;
        } else {
            return false;
        }
    }
}