(PowerShell) Google Authenticator Algorithm

Example code implementing the Google Authenticator algorithm.

Chilkat .NET Downloads Chilkat .NET Assemblies

Add-Type -Path "C:\chilkat\ChilkatDotNet47-9.5.0-x64\ChilkatDotNet47.dll"

# 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 = New-Object Chilkat.Crypt2
$otp = $crypt.Totp($secretBase32,"base32","0","",30,6,-1,"sha1")

$("6-digit decimal token = " + $otp)