How to connect google authenticator?

Question

PHP

Hello,
we connect google authenticator. At the stage of the first scanning of the qr code from the google authenticator application, the "invalid key" error appears.
Has anyone connected google authenticator? It feels like we have to feed the host somewhere to generate the qr code, but this is not in the documentation. Or is there a problem in the library ..., then which one is exactly working?

Answer 1

It's hard to tell what's wrong with you because you didn't provide the code. Probably, the QR was crooked, since the error occurs when scanning it. You can read more about how to compose a URL for a QR code in the wiki .
I have implemented Google Authenticator in my project without any problems. I'm using the sonata-project/google-authenticator package .
Code generation:

$g = new \Google\Authenticator\GoogleAuthenticator();
$secret = $g->generateSecret();
echo '<img src="https://chart.googleapis.com/chart?'
  .'cht=qr&chl=otpauth://totp/mysite%3Fsecret%3D'
  .$secret.'&chs=200x200&chld=L|0" />';

The $secret value is stored in the database and tied to a specific user.
OTP check:

$g = new \Google\Authenticator\GoogleAuthenticator();
if ($g->checkCode($secret, $code)) {
  echo 'Welcome!'
} else {
  echo 'Wrong code';
}

Code examples are provided for library version 1.0.2.
An important point is that the time on the server and on the phones must match in order for the generated OTPs to match. Therefore, the server is synchronized using the NTP protocol. Phones are more difficult. You can set the synchronization of the phone's clock with the time from the GSM network in the system settings (for any platform), or in the settings of the Google Authenticator application (there is in the android version, not in the iOS version, do not know about other platforms).