FIDO 2.0 (FIDO2) is an open authentication standard that enables people to leverage common devices to authenticate to online services in both mobile and desktop environments.
FIDO2 is comprised of the W3C’s Web Authentication specification (WebAuthn) and FIDO’s corresponding Client-to-Authenticator Protocol (CTAP). WebAuthn defines a standard web API that can be built into browsers and related web platform infrastructure to enable online services to use FIDO Authentication. CTAP enables external devices such as mobile handsets or FIDO Security Keys to work with WebAuthn and serve as authenticators to desktop applications and web services.
This document explains how to use the Gluu Server's included FIDO2 interception script to implement a two-step, two-factor authentication (2FA) with username / password as the first step, and any FIDO2 device as the second step.
- A Gluu Server (installation instructions);
- FIDO2 interception script (included in the default Gluu Server distribution);
- At least one FIDO2 device for testing, like one of the devices listed below.
- For Linux-based operating systems, a little modification required in udev rule, that is stated below.
Some well known FIDO2 devices and manufacturers include:
The script has the following properties
|URL of the oxAuth FIDO2 server
Enable FIDO2 script#
Follow the steps below to enable FIDO2 authentication:
Manage Custom Scripts.
Click on the
Enable the script by checking the box
Scroll to the bottom of the page and click
Now FIDO2 is an available authentication mechanism for your Gluu Server. This means that, using OpenID Connect
acr_values, applications can now request FIDO2 authentication for users.
To make sure FIDO2 has been enabled successfully, you can check your Gluu Server's OpenID Connect
configuration by navigating to the following URL:
"acr_values_supported": and you should see
Enable FIDO2 endpoints#
By default, the FIDO2 endpoints are disabled in the Gluu Server for compatibility with older versions. To activate the endpoints, follow these steps:
Click on the
Scroll down to the Fido2 Specification
Save Configurationbutton at the bottom of the page.
Make FIDO2 the Default#
If FIDO2 should be the default authentication mechanism, follow these instructions:
Default Authentication Methodtab.
In the Default Authentication Method window you will see two options:
oxTrust acrsets the authentication mechanism for accessing the oxTrust dashboard GUI (only managers should have acccess to oxTrust).
Default acrsets the default authentication mechanism for accessing all applications that leverage your Gluu Server for authentication (unless otherwise specified).
If FIDO2 should be the default authentication mechanism for all access, change both fields to
If FIDO2 is set as a default authentication mechanism users will not be able to access the protected resource(s) while using a mobile device or a browser that does not support FIDO2 (e.g. Internet Explorer).
FIDO2 login page#
Below is an illustration of the Gluu Server's default FIDO2 login page:
Using FIDO2 tokens#
FIDO2 device enrollment happens during the first authentication attempt.
All subsequent FIDO2 authentications for that user account will require the enrolled FIDO2 key.
FIDO2 credential management#
A user's FIDO2 devices can be removed by a Gluu administrator in LDAP under the user entry as shown in the below screenshot.
FIDO2 discovery endpoint#
A discovery document for FIDO2 is published by the Gluu Server at:
https://<hostname>/.well-known/fido2-configuration This document specifies the URL of the registration and authentication endpoints.
FIDO2 in Linux#
Older versions of Linux may require a rules file to be backwards compatible with Hypersecu devices. From your terminal run the below commands and reboot your computer.
sudo curl https://hypersecu.com/downloads/files/configurations/70-u2f.rules > /etc/udev/rules.d/70-u2f.rules
chmod +x /etc/udev/rules.d/70-u2f.rules