A note on vendor reaction speed to the e=3 problem

[David Shaw]

On Sat, Sep 16, 2006 at 05:35:27AM +1200, Peter Gutmann wrote:
> David Shaw <dshaw at jabberwocky.com> writes:
> 
> >Incidentally, GPG does not attempt to parse the PKCS/ASN.1 data at all.
> >Instead, it generates a new structure during signature verification and
> >compares it to the original.
> 
> How does it handle the NULL vs.optional parameters ambiguity?

GPG generates a new structure for each comparison, so just doesn't
include any extra parameters on it.  Any optional parameters on a
signature would cause that signature to fail validation.

RFC-2440 actually gives the exact bytes to use for the ASN.1 stuff,
which nicely cuts down on ambiguity.

David

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