How to redirect an entire range/block of IP addresses with PHP?

Question

I'm using the following snippet to redirect an array of IP addresses. I was wondering how I would go about adding an entire range/block of IP addresses to my dissallowed array...

<?php // Let's redirect certain IP addresses to a "Page Not Found"
$disallowed = array("76.105.99.106");
$ip = $_SERVER['REMOTE_ADDR']; 

if(in_array($ip, $disallowed)) {
 header("Location: http://google.com");
 exit;
}
?>

I tried using "76.105.99.*", "76.105.99", "76.105.99.0-76.105.99.255" without any luck.

I need to use PHP rather than mod_rewrite and .htaccess for other reasons.

Answer 1

Here's an example of how you could check a particular network/mask combination:

$network=ip2long("76.105.99.0");
$mask=ip2long("255.255.255.0");
$remote=ip2long($_SERVER['REMOTE_ADDR']);

if (($remote & $mask)==$network)
{
    header("Location: http://example.com");
    exit;
}

This is better than using a string based match as you can test other masks that align within an octet, e.g. a /20 block of IPs

Answer 2

Try the substr function:

$ip = '76.105.99.';
if (substr($_SERVER['REMOTE_ADDR'], 0, strlen($ip)) === $ip) {
    // deny access
}

Answer 3

You can approach the problem in a different way.

If you want to ban 76.105.99.* you could do:

if (strpos($_SERVER['REMOTE_ADDR'], "76.105.99.")!==FALSE)
{
    header ('Location: http://google.com');
} 

Answer 4

Who exactly are you interested in blocking? You can use PHP or apache to block (or allow) a bunch of specific IP addresses.

If you are interested in blocking people from an entire country for example, then there are tools that give you the IP addresses you need to block. Unfortunately, it's not as simple as just specifying a range.

Check out http://www.blockacountry.com/ which generates a bunch of ip addresses you can stick in your .htaccess to block whole countries.