(PHP ActiveX) Google Authenticator Algorithm

Example code implementing the Google Authenticator algorithm.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows Note: The php_com_dotnet.dll may need to be enabled inside of php.ini.

<?php

// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

// Generating TOTP Base32 Secret: 
// When you enable 2FA with a TOTP-based authenticator app, Google will provide you with a QR code
// that you can scan using the app. This QR code contains a TOTP base32 secret.
// You can also choose to view and copy the secret manually.

$secretBase32 = 'JBSWY3DPEHPK3PXP';

// Do the following to calculate the 6-digit decimal Google authenticator token for a base32 secret,
// given the current system date/time.
// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.Crypt2')
$crypt = new COM("Chilkat.Crypt2");
$otp = $crypt->totp($secretBase32,'base32','0','',30,6,-1,'sha1');

print '6-digit decimal token = ' . $otp . "\n";

?>