WebAuthn Provider for TYPO3 Multi Factor Authentication

This TYPO3 extension integrates into the TYPO3 Multi Factor Authentication (MFA) API, adding authenticators using the WebAuthn standard. It provides support for FIDO2/U2F Hardware tokens and Internal Authenticators (e.g. Android Screenlock or Windows hello) as second factor during authentication.

Installation

composer require bnf/mfa-webauthn

Prerequisites and Limitations

The WebAuthn API has some design-driven limitations. Authentication is reserved for secure environments in order to prevent spoofing of credentials, and therefore a WebAuthn credential is additonally bound to a domain.

This puts the following limitations on usages of this provider:

• Requires a valid SSL certificate or a localhost environment (therefore use http://{myproject}.localhost as local development URL)
• Works only for one domain, multi domain sites need to have TYPO3 backend redirected to exactly one domain, or should use alternative MFA providers.

Using WebAuthn Provider in production and staging environments

It is still possible to use WebAuthn in production and staging environments, but it requires some manual steps:

1. Create a security token in the production environment.
2. Create recovery codes or register a time-based one-time password (TOTP) in production.
3. Sync the `be_user' table from production to staging.
4. Log in to staging with a recovery code or TOTP.
5. Create a security token in the staging environment.
6. Sync the user's `be_users.mfa' database field back to production.
7. Optional: Regenerate recovery codes in production to have a fresh set of tokens.

Alternative Extensions

If the restriction to one backend domain is too limiting, consider using mfa_yubikey or mfa_hotp instead. Note, both providers are less secure than webauthn, as the user can be spoofed with a faked domain name, but they are more flexible and both allow to use hardware tokens with a multi domain setup. (mfa_hotp is intended for software HOTP authenticators, but the HOTP secret can also be burned to cheap HOTP hardware tokens.)