Possible crypto backdoor in RFC-2631 Diffie-Hellman Key Agreement Method

[Georgi Guninski]

On Thu, Sep 03, 2015 at 01:33:48PM +0000, Peter Gutmann wrote:
> Georgi Guninski <guninski at guninski.com> writes:
> 
> >Anyway, I would appreciate if someone checks if current implementations
> >accept composite $q$.
> 
> Well, I think the problem will be finding any implementation of this at all,
> or at least any that's still around now.
> 
> >What do you mean by DH certificate?
> 
> The static DH parameters need to be turned into a certificate by a CA.  I
> don't know of any public CA that can issue these.
> 
> Peter.

Well openessl appears to support dhparam:
https://www.openssl.org/docs/manmaster/apps/dhparam.html

(maybe one needs to patch the source).

Maybe the same approach will work for DSA.