Use Authenticator to Generate Two-Factor Authentication Codes on Linux 2022

For a simple, straight-forward way to generate two factor authentication codes on Ubuntu and other Linux desktops try Authenticator.

Created by developer Bilal Elmoussaoui, ‘Authenticator‘ is a GTK app you can use to get secure two-factor authentication codes to use with more than 200 providers, including GitHub, Microsoft, Twitter, Facebook, Google, and Dropbox.

And if you want to know if this apps supports a particular service before you install it search for it on the 2fa.directory. If a service listed on that website supports ‘software tokens’ then it will work with it.

In this post I take a quick look at what two-factor authentication is, why it’s (highly) recommended, and how Authenticator makes using the codes it creates seriously simple.

What is Two Factor Authentication?

Two-factor authentication is one of the best way to secure your online accounts as it requires you to “authenticate” twice when signing into a service, app or site: once with your regular user password; second with a time-limited code generated by an authentication app or sent to you via SMS.

Think of it like needing two keys to your apartment: one to open the door, and one to prove it’s you who wants to get in.

The idea of 2FA (as the cool kids call it) is that should anyone steal or crack your password they can’t use it in isolation as the requirement for a secondary code, which, in some cases, has to be generated for every new login, creates a hurdle a would-be rogue has to clear without you being notified.

Scores of websites, online services, and apps offer improved account security using two-factor codes. The codes you need can be generated by an app you install on your mobile device as well as an app you have on your desktop.

Authenticator: 2-Factor Auth for Linux Desktop

Authenticator is a GTK application for GNOME-based desktops. It allows you to set-up two-factor authentication for multiple sites, apps, and services including:

It also has a bunch of other features:

• Time-based/Counter-based/Steam methods support
• SHA-1/SHA-256/SHA-512 algorithms support
• QR code scanner using a camera or from a screenshot
• Lock the application with a password
• GNOME Shell search provider
• Backup/Restore from/into other 2FA applications

To get started click the + button in the tool bar and search the built-in list of providers for you account, and enter the details as prompted.

But my tip is to use the QR Code scanner that Authenticator has built-in.

Almost every major 2FA provider will create a QR code you can scan with an authenticator app. How to do that on a desktop? Authenticator can use your webcam to scan a QR code (e.g., one on your phone) or scan from a desktop screenshots that contains a QRcode – i.e. hit prnt scrn then open the image in the app to add the account.

A little-known secret, but you can use multiple authentication tools with most 2FA services. I have my main accounts set-up in Google Authenticator app on my phone and Authenticator on my Linux desktop.

This way, rather than reaching into my pocket for my phone each time I’m prompted to enter a code, I can open this app on my desktop and copy-paste the six-digit auth code across.

Install Authenticator

You can install the latest version of Authenticator from Flathub. This is the recommended way to get the app. Just visit the Flathub website, click the “install” button, and the GNOME Software app should do the rest.

If you have Flatpak and Flathub already setup on your system you may prefer to install Authenticator from the command line, using:

flatpak install flathub com.bilelmoussaoui.Authenticator

Alternatively you can build the source code available to download from the project’s Gitlab page.

An unofficial (and, at the time of writing out-dated) version is available from the Snap Store, while users of Arch-based Linux distributions can get Authenticator on the AUR.