general_functions.inc.php

<?php

function isValidIP($ip)
{
	if (!empty($ip) && ip2long($ip) != -1) {
		$reserved_ips = array
		(
			array('0.0.0.0','2.255.255.255'),
			array('10.0.0.0','10.255.255.255'),
			array('127.0.0.0','127.255.255.255'),
			array('169.254.0.0','169.254.255.255'),
			array('172.16.0.0','172.31.255.255'),
			array('192.0.2.0','192.0.2.255'),
			array('192.168.0.0','192.168.255.255'),
			array('255.255.255.0','255.255.255.255')
		);
		foreach ($reserved_ips as $r) {
			$min = ip2long($r[0]);
			$max = ip2long($r[1]);
			if ((ip2long($ip) >= $min) && (ip2long($ip) <= $max)) {
				return false;
			}
		}
		return true;
	} else {
		return false;
	}
}


function getIP()
{

	if (!empty($_SERVER['HTTP_CLIENT_IP']) && isValidIP($_SERVER['HTTP_CLIENT_IP'])) {
		return $_SERVER["HTTP_CLIENT_IP"];
	}

	if (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) {
		foreach (explode(',', $_SERVER['HTTP_X_FORWARDED_FOR']) as $ip) {
			if (isValidIP(trim($ip))) {
				return $ip;
			}
		}
	}

	if (!empty($_SERVER['HTTP_X_FORWARDED']) && isValidIP($_SERVER['HTTP_X_FORWARDED'])) {
		return $_SERVER['HTTP_X_FORWARDED'];
	} elseif (!empty($_SERVER['HTTP_FORWARDED_FOR']) && isValidIP($_SERVER['HTTP_FORWARDED_FOR'])) {
		return $_SERVER['HTTP_FORWARDED_FOR'];
	} elseif (!empty($_SERVER['HTTP_FORWARDED']) && isValidIP($_SERVER['HTTP_FORWARDED'])) {
		return $_SERVER['HTTP_FORWARDED'];
	} elseif (!empty($_SERVER['HTTP_X_FORWARDED']) && isValidIP($_SERVER['HTTP_X_FORWARDED'])) {
		return $_SERVER['HTTP_X_FORWARDED'];
	} else {
		return $_SERVER['REMOTE_ADDR'];
	}
}


function forceHTTPS()
{
	if (isset($_SERVER)) {
		if (!isset($_SERVER['HTTPS']) || strtolower($_SERVER['HTTPS']) != 'on') {
			header('Location: https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI']);
			exit;
		}
	}
}


function getPageAliasUsingURL()
{
	$url = $_SERVER['SCRIPT_NAME'] ? $_SERVER['SCRIPT_NAME'] : $_SERVER['PHP_SELF'];
	$alias = str_replace('index.php', '', $url);
	// Remove first /
	while (substr($alias, 0, 1) == '/') {
		$alias = substr($alias, 1);
	}
	// Remove lasst /
	while (substr($alias, strlen($alias) - 1, 1) == '/') {
		$alias = substr($alias, 0, strlen($alias) - 1);
	}
	// Just take what comes after the LAST /
	if (strpos($alias, '/') !== false) {
		$alias = substr($alias, strrpos($alias, '/') + 1);
	}
	return $alias;
}


function isEmailValid($email)
{
	if (preg_match('/^([a-zA-Z0-9])+([a-zA-Z0-9\._-]).*@([a-zA-Z0-9_-])+([a-zA-Z0-9\._-]+)+$/', $email)) {
		list($username, $domain) = split('@', $email);
		if (!checkdnsrr($domain, 'MX')) {
			return false;
		}
	}
	return true;
}