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PHP Extension

TOTP Authenticator: Duplicate Results of Online Tools

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Duplicates the online tool for the Google 2FA Authenticator online tools at

Chilkat PHP Extension Downloads

PHP Extension
<?php

include("chilkat.php");

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.
// 
// Note: This example was written on 7-March-2020.  If the online tools have since changed, the instructions provided here may no longer be valid.
// 

$crypt = new CkCrypt2();

// ---------------------------------------------------------------------------------------------
// To duplicate the results of the Authenticator Test at https://rootprojects.org/authenticator/
// do the following:
// 1) At the bottom of the screen you will see a URI such as:
// 
//    otpauth://totp/ACME%20Co:john@example.com?secret=HXDMVJECJJWSRB3HWIZR4IFUGFTMXBOZ&issuer=ACME%20Co&algorithm=SHA1&digits=6&period=30
// 
//    Use the uppercase secret.  For example:
$secretKey = 'HXDMVJECJJWSRB3HWIZR4IFUGFTMXBOZ';

// 2) DO NOT cick the "Regenerate" button.  The regenerate button will generate a new secret.
// 
// 3) Run the following code to generate your 6-digit token.  Compare with the token shown in the picture of the iPhone at https://rootprojects.org/authenticator/
//      Note: A new token is generated every 30 seconds.  You must generate within the same 30 second interval to get the same result.
print 'Your token is: ' . $crypt->totp($secretKey,'base32','0','',30,6,-1,'sha1') . "\n";

// ---------------------------------------------------------------------------------------------
// To duplicate the results of the Google2FA Playground at https://pragmarx.com/playground/google2fa#/
// do the following:

// 1) Copy the 64-byte secret key:
$secretKey = 'OR2VQTRVHB2HO2LCGVWXQSCDK5ZHQS2D3THQ6UXO57XIE7ZHOWS6HDPQ622GU747';

// 2) Run the same code:
//    (Note: The online tool generates a new result every 30 seconds.  You must generate and compare within the same 30-second interval.)
print 'Your token is: ' . $crypt->totp($secretKey,'base32','0','',30,6,-1,'sha1') . "\n";

?>