Re: [Cfrg] testability of signature input/output parameters

[Nico Williams <[e-mail]>]

On Thu, Jun 04, 2015 at 10:13:02AM -0700, Mike Hamburg wrote:
> Obviously the coverage you get from this varies by primitive, so AES
> is more testable than signing.  Fine.  But specifying deterministic
> signatures still improves testability, to a degree that will be
> useful in the real world.

Deterministic signatures do much more than make it easier to test
implementations: they also remove hidden state and/or dependency on
TRNGs (and in the process, one more possible place to check has no side
channels).  This is a big deal.  Tests shows the implementation works,
and determinism shows the implementation should continue to work when
used in production.

Nico
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