ip.php

<?php
// Non existing function usage in PHP 5.3 and older degrade gracefully
// This is no longer available in BlueHost since 2017-11-15 as their minimum PHP version is 5.4

$remip = getip();
echo trim($remip);

// Check if ip adddress is valid
// https://github.com/carriercomm/NeoBill/blob/master/modules/nullregistrar/phpwhois/whois.ip.lib.php
// https://github.com/phpWhois/phpWhois/blob/4-stable/src/whois.ip.lib.php
// https://github.com/phpWhois/phpWhois/blob/master/src/IpTools.php

function validip($ip) {

	if (empty($ip))
		return false;

	if ((ip2long($p) == -1) or (ip2long($p) === false))
		return false;

	$reserved_ips = array (
			array('0.0.0.0','2.255.255.255'),
			array('10.0.0.0','10.255.255.255'),
			array('127.0.0.0','127.255.255.255'),
			array('169.254.0.0','169.254.255.255'),
			array('172.16.0.0','172.31.255.255'),
			array('192.0.2.0','192.0.2.255'),
			array('192.168.0.0','192.168.255.255'),
			array('255.255.255.0','255.255.255.255')
			);

	foreach ($reserved_ips as $r) {

		$min = ip2long($r[0]);
		$max = ip2long($r[1]);
		if ((ip2long($ip) >= $min) && (ip2long($ip) <= $max)) return false;
	}

	return true;
}

function getip() {
	if (isset($_SERVER["HTTP_CLIENT_IP"]) && validip($_SERVER["HTTP_CLIENT_IP"])) {
		return $_SERVER["HTTP_CLIENT_IP"];
	}
	if (isset($_SERVER["HTTP_X_FORWARDED_FOR"])) {
		foreach (explode(",",$_SERVER["HTTP_X_FORWARDED_FOR"]) as $ip) {
			if (validip(trim($ip))) {
				return $ip;
			}
		}
	}
	if (isset($_SERVER["HTTP_X_FORWARDED_FOR"]) && validip($_SERVER["HTTP_X_FORWARDED_FOR"])) {
		return $_SERVER["HTTP_X_FORWARDED_FOR"];
	} elseif (isset($_SERVER["HTTP_FORWARDED_FOR"]) && validip($_SERVER["HTTP_FORWARDED_FOR"])) {
		return $_SERVER["HTTP_FORWARDED_FOR"];
	} elseif (isset($_SERVER["HTTP_FORWARDED"]) && validip($_SERVER["HTTP_FORWARDED"])) {
		return $_SERVER["HTTP_FORWARDED"];
	} elseif (isset($_SERVER["HTTP_X_FORWARDED"]) && validip($_SERVER["HTTP_X_FORWARDED"])) {
		return $_SERVER["HTTP_X_FORWARDED"];
	} else {
		return $_SERVER["REMOTE_ADDR"];
	}
}
?>