U2F NFC authentication flow

2016-01-20T11:19:06+01:00

With a USB FIDO U2F key, the authentication flow is handled by the browser on the client side (today this means Chrome, but Firefox seems committed as well) where the low-level JavaScript API is available. Yubico has provided the high-level JavaScript API by means of a small library (as documented here).

The steps are basically these:

Get challenge from server (server generates challenge for registered devices)
Sign with U2F key (user touches button of key)
Send response to server (server validates response)

How does this work with NFC FIDO U2F keys such as the Yubikey Neo? If I am reading the specifications correctly, the server-side of the authentication flow is exactly the same. Is the same high-level JasvaScript API used in the browser? That is, does Chrome on Android provide the low-level JavaScript API for use with an NFC FIDO U2F token, or is another tool such as Google Authenticator required?

Statistics: Posted by jdhoek — Wed Jan 20, 2016 11:19 am

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U2F NFC authentication flow