polhenarejos/pico-fido

OTP static key limited to 8 characters instead of 32 on pico

Closed this issue · 4 comments

niansa commented 
$ ykman otp static 1 DrHfEHtICeCeNuEjkfHJdCGuvbhEhGvDenecgk
Slot 1 is already configured. Overwrite configuration? [y/N]: y

Stored password ends up being: DrHfEHtI

polhenarejos commented

Did you try it with a legit Yubikey? It seems that YKMAN supports 16 bytes for static OTP (if you have 8 might be caused by SHORT_TICKET flag).

polhenarejos commented

From Yubico documentation, static passwords are 16 bytes length:

https://docs.yubico.com/yesdk/users-manual/application-otp/commands-configure-slot.html

From specs, it cannot increased, as it would overflow the frame buffer.

niansa commented

But then why can it only be 8, not 16?

polhenarejos commented

Not really. In version 5.8 we removed that limitation and Pico Fido is able to send up to 38 bytes.

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