From: Anil Das <das@razor.engr.sgi.com>
Date: Wed, 29 Jan 1997 07:18:20 -0800 (PST)
To: James Robertson <jamesr@magna.com.au>
Subject: Re: [DES] DES Key Recovery Project, Progress Report #7
Message-ID: <199701291518.HAA03774@toad.com>
MIME-Version: 1.0
Content-Type: text/plain


On Jan 25, 10:49am, James Robertson wrote:
> 
> Are there any efforts being made to develop a version of the
> software that can be used by us non-US residents?
> 
> I would certainly like to participate in the Challenge. I'm 
> sure there are many other interested people out there, in the
> big wide world ...

No such development outside the US has been publicized.

However, it is easy enough to roll your own.

What you need:

1) Eric Young's libdes. ftp://ftp.psy.uq.oz.au/pub/Crypto/DES

2) Svend Olaf Mikkelsen's fast replacement for the core DES routine.
http://inet.uni-c.dk/~svolaf/des.htm
The latest libdes is supposed to have this faster routine incorporated
already, so you may not need it.

3) Peter Trei's article on "Optimizing DES Key Recovery in Software".
It is available at HKS's news server.
news://nntp.hks.net/<199610171918.MAA23054@toad.com>

For a first pass, you can just implement the Gray Code technique. That
gives most of the speedup.

4) Some information on how to implement Gray Codes.
"The Gray Code" by Robert W. Doran. Tech Report 131 from
http://www.cs.auckland.ac.nz/~techrep/1996.html

Given these resources, it shouldn't take long for a
good programmer to implement a DES key search program that
is in the same ballpark of performance as Peter Trei's implementation.

--
Anil Das