Hi Kathryn,

On Wed, Sep 27, 2017 at 05:37:36PM -0400, Kathryn Heckman wrote:
> Is there any way to retrieve the value of OP from OPc and Ki?

No, that defeats the entire purpose of having card-individual OPc
values.

If you could just revert that operation, there would be no [security]
advantage of card-individual OPc values over a global OP value, and
hence that entire option could be dropped from the specifications
altogether.

Regards,
        Harald
--
- Harald Welte <laforge@gnumonks.org>           http://laforge.gnumonks.org/
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