Re: Replacing the EDH SKIP primes

On Tue, Jun 18, 2019 at 02:05:00PM +0200, Daniel Gustafsson wrote:
> The current hardcoded EDH parameter fallback use the old SKIP primes, for which
> the source disappeared from the web a long time ago.  Referencing a known dead
> source seems a bit silly, so I think we should either switch to a non-dead
> source of MODP primes or use an archive.org link for SKIP.  Personally I prefer
> the former.

I agree with you that it sounds more sensible to switch to a new prime
instead of relying on an archive of the past one.

> This was touched upon, but never really discussed AFAICT, back when then EDH
> parameters were reworked a few years ago.  Instead of replacing with custom
> ones, as suggested in [1] it we might as well replace with standardized ones as
> this is a fallback.  Custom ones wont make it more secure, just add more work
> for the project.  The attached patch replace the SKIP prime with the 2048 bit
> MODP group from RFC 3526, which is the same change that OpenSSL did a few years
> back [2].

Fine by me.  Let's stick with the 2048b-long one for now as we did in
c0a15e0.  I am wondering if we should sneak that into v12, but I'd
rather just wait for v13 to open.
--
Michael