I've been investigating the implementation of CTAP2 protocol with Google Chrome (protocol between Fido Authenticator and Fido Client (e.g. Chrome)), which should be supported in Chrome since version 69.

So I dumped the chrome request to the authenticator in two cases:

1. U2F (CTAP1) with yubico demo website.

Here everything goes as expected and chrome follows the CTAP1 protocol.

2. FIDO2/Webauthn (CTAP2) with webauthn.org

And the browser has a strange behaviour:

  • It starts by following the CTAP2 protocol by sending a AuthenticatorGetInfoRequest
  • The Authenticator replies with AuthenticatorGetInfoResponse
  • But then Chrome switches to the CTAP1 protocol by sending a Registration Request Message (U2F_REGISTER)

Is it a problem with Chrome implementation: CTAP2 is not enabled entirely yet (it seems to be implemented in Chromium sources)?

Or is the problem coming from the authenticator: sending a response that makes Chrome switch to CTAP1?

Or something else entirely?

Your Answer

By clicking "Post Your Answer", you acknowledge that you have read our updated terms of service, privacy policy and cookie policy, and that your continued use of the website is subject to these policies.

Browse other questions tagged or ask your own question.