星期一, 8月 01, 2005

A better way to detect IP in PHP

Sometimes we cannot get the correct IP of the client by $_SERVER['REMOTE_ADDR'], so we need the following function!
<?php
function getrealip()
{
    
$ip = FALSE;
    if (!empty(
$_SERVER["HTTP_CLIENT_IP"])) {
        
$ip = $_SERVER["HTTP_CLIENT_IP"];
    }

    if (!empty(
$_SERVER['HTTP_X_FORWARDED_FOR'])) {
        
$ips = explode (", ", $_SERVER['HTTP_X_FORWARDED_FOR']);
        if (
$ip) {
            
array_unshift($ips, $ip);
            
$ip = FALSE;
        }

        for (
$i = 0; $i < count($ips); $i++) {
            if (!
eregi ("^(10|172\.16|192\.168)\.", $ips[$i])) {
                if (
version_compare(phpversion(), "5.0.0", ">=")) {
                    if (
ip2long($ips[$i]) != false) {
                        
$ip = $ips[$i];
                        break;
                    }
                } else {
                    if (
ip2long($ips[$i]) != -1) {
                        
$ip = $ips[$i];
                        break;
                    }
                }
            }
        }
    }
    return (
$ip ? $ip : $_SERVER['REMOTE_ADDR']);
}
?>

沒有留言: