(Perl) Google Authenticator Algorithm

Example code implementing the Google Authenticator algorithm.

Chilkat Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux, Solaris

use chilkat();

# 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.
$crypt = chilkat::CkCrypt2->new();
$otp = $crypt->totp($secretBase32,"base32","0","",30,6,-1,"sha1");

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