function getIP()

{

// Find the user's IP address. (but don't let it give you 'unknown'!)

if (!empty($_SERVER['HTTP_X_FORWARDED_FOR']) && !empty($_SERVER['HTTP_CLIENT_IP']) && (preg_match('~^((0|10|172\.16|192\.168|255|127\.0)\.|unknown)~', $_SERVER['HTTP_CLIENT_IP']) == 0 || preg_match('~^((0|10|172\.16|192\.168|255|127\.0)\.|unknown)~', $_SERVER['REMOTE_ADDR']) != 0))

{

// We have both forwarded for AND client IP... check the first forwarded for as the block - only switch if it's better that way.

if (strtok($_SERVER['HTTP_X_FORWARDED_FOR'], '.') != strtok($_SERVER['HTTP_CLIENT_IP'], '.') && '.' . strtok($_SERVER['HTTP_X_FORWARDED_FOR'], '.') == strrchr($_SERVER['HTTP_CLIENT_IP'], '.') && (preg_match('~^((0|10|172\.16|192\.168|255|127\.0)\.|unknown)~', $_SERVER['HTTP_X_FORWARDED_FOR']) == 0 || preg_match('~^((0|10|172\.16|192\.168|255|127\.0)\.|unknown)~', $_SERVER['REMOTE_ADDR']) != 0))

$_SERVER['REMOTE_ADDR'] = implode('.', array_reverse(explode('.', $_SERVER['HTTP_CLIENT_IP'])));

else

$_SERVER['REMOTE_ADDR'] = $_SERVER['HTTP_CLIENT_IP'];

}

if (!empty($_SERVER['HTTP_CLIENT_IP']) && (preg_match('~^((0|10|172\.16|192\.168|255|127\.0)\.|unknown)~', $_SERVER['HTTP_CLIENT_IP']) == 0 || preg_match('~^((0|10|172\.16|192\.168|255|127\.0)\.|unknown)~', $_SERVER['REMOTE_ADDR']) != 0))

{

// Since they are in different blocks, it's probably reversed.

if (strtok($_SERVER['REMOTE_ADDR'], '.') != strtok($_SERVER['HTTP_CLIENT_IP'], '.'))

$_SERVER['REMOTE_ADDR'] = implode('.', array_reverse(explode('.', $_SERVER['HTTP_CLIENT_IP'])));

else

$_SERVER['REMOTE_ADDR'] = $_SERVER['HTTP_CLIENT_IP'];

}

elseif (!empty($_SERVER['HTTP_X_FORWARDED_FOR']))

{

// If there are commas, get the last one.. probably.

if (strpos($_SERVER['HTTP_X_FORWARDED_FOR'], ',') !== false)

{

$ips = array_reverse(explode(', ', $_SERVER['HTTP_X_FORWARDED_FOR']));

 
// Go through each IP...

foreach ($ips as $i => $ip)

{

// Make sure it's in a valid range...

if (preg_match('~^((0|10|172\.16|192\.168|255|127\.0)\.|unknown)~', $ip) != 0 && preg_match('~^((0|10|172\.16|192\.168|255|127\.0)\.|unknown)~', $_SERVER['REMOTE_ADDR']) == 0)

continue;

 
// Otherwise, we've got an IP!

$_SERVER['REMOTE_ADDR'] = trim($ip);

break;

}

}

// Otherwise just use the only one.

elseif (preg_match('~^((0|10|172\.16|192\.168|255|127\.0)\.|unknown)~', $_SERVER['HTTP_X_FORWARDED_FOR']) == 0 || preg_match('~^((0|10|172\.16|192\.168|255|127\.0)\.|unknown)~', $_SERVER['REMOTE_ADDR']) != 0)

$_SERVER['REMOTE_ADDR'] = $_SERVER['HTTP_X_FORWARDED_FOR'];

}

elseif (!isset($_SERVER['REMOTE_ADDR']))

$_SERVER['REMOTE_ADDR'] = '';

}