test.php

<?php
header("Cache-Control: no-cache");
?>
<form name="input" action="" method="get">
AES ENC: <input type="text" name="enc" />
<input type="submit" value="Submit" />
</form>
<?php
$message 	= urldecode(utf8_encode($_GET['enc']));
$pwd = 'aaafffaa12345678';
echo 'Test result: ';
echo $message 	= getDecrypt($message, $pwd);
$messages	= explode('/', $message);
$user_id	= $messages['0'];
$period		= $messages['1'];
$current_time = current_millis();


//300000 - 5 mins
//60000 - 1min
if($current_time - $period  >= 300000){
	print('<br><br>'.$user_id .', timed out!');
}else{
	print('<br><br>Welcome '. $user_id);
}
echo '<br> Key Time at '.datetimems($period).' TS:('.$period.')';
echo '<br> Current Time '.datetimems($current_time).' TS:('.$current_time.')';
echo '<hr><br>';
echo '<strong>Encrption of User ID & TS : 9028019/'.$current_time.'</strong><br><hr>';
echo 'encrypted : '.$enc = getEncrypt('9028019/'.$current_time,$pwd);
echo '<br><a href="test.php?enc='.urlencode($enc).'">TEST</a></h3><br>';

echo '<hr><br><strong>Decryption of above encrypted string</strong><br><hr>';
echo 'decrypted :   '.getDecrypt($enc, $pwd);

function datetimems($ts){
	$mil = $ts;
	$seconds = $mil / 1000;
	return $datetime = date("Y-m-d H:i:s", $seconds); 
}

function getDecrypt($string, $key) {
	return mcrypt_decrypt(
		MCRYPT_RIJNDAEL_128, 
		$key, 
		base64_decode($string), 
		MCRYPT_MODE_ECB
	);
}
	// resturn encrpted string
function getEncrypt($sStr, $sKey) {
	return base64_encode(
		mcrypt_encrypt(
			MCRYPT_RIJNDAEL_128, 
			$sKey,
			$sStr,
			MCRYPT_MODE_ECB
		)
	);
}

// return our current unix time in millis
function current_millis($e = 7) {
	list($usec, $sec) = explode(" ", microtime());
	return round(((float)$usec + (float)$sec) * 1000);
	//return round(( bcadd($usec, $sec, $e) ) * 1000);
}