Implementation of the openpgp smartcard specification 2.0 for zeitcontrol basiccard

NIIBE Yutaka gniibe at
Mon Apr 6 04:13:15 CEST 2015

On 04/04/2015 11:50 PM, Klaus Flittner wrote:
> Recently i found the code again and thought it might be of interest
> to some of you.

Great.  Thank you for sharing your experience.

> In comparison to the official OpenPGP card, this implementation
> allows command chaining and should thus allow larger keys with more
> readers, since in my experience extended APDU are not well supported
> in most smartcard readers.

I agree.

In Gnuk, I use short APDU + command chaining + get response.  In the
beginning of the project, I used extended APDU format, as it looked
simple and easy.  But I found contrary, in fact.

Short APDU is good for host environment, too.  One of major reasons
why I dropped extended APDU in Gnuk was I found a bug in a version of
libusbx which caused a problem by larger packet (it was around 2012).

I believe that it is better for card and token implementations to
support short APDU and command chaining.

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