/**
* @expectedException \chillerlan\Base32\Base32Exception
* @expectedExceptionMessage Must match character set
*/
public function testToBinCharsetException()
{
Base32::toBin('MFRGGZDFMZTÖ');
}
/**
* Calculate the code with the given secret and point in time
*
* @param string $secret
* @param float $timeslice -> floor($timestamp / 30)
*
* @return string
* @throws \chillerlan\GoogleAuth\AuthenticatorException
*/
public static function getCode($secret, $timeslice = null)
{
self::checkSecret($secret);
// Pack time into binary string
$time = str_repeat(chr(0), 4);
$time .= pack('N*', self::checkTimeslice($timeslice));
// Hash it with users secret key
$hmac = hash_hmac('SHA1', $time, Base32::toString($secret), true);
// Use last nibble of result as index/offset
$offset = ord(substr($hmac, -1)) & 0xf;
// Unpack binary value, only 32 bits
$value = unpack('N', substr($hmac, $offset, 4))[1] & 0x7fffffff;
return str_pad($value % pow(10, self::$digits), self::$digits, '0', STR_PAD_LEFT);
}
