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Date: Wed, 08 Feb 2006 19:43:47 +0100
From: Michal Luczaj <>
Subject: Re: DIGEST-MD5, dominosec optimization

Solar Designer wrote:
> I won't spend much time on this discussion since the time would be
> better spent actually optimizing the code and integrating it into John.

Sure thing.

> However, the really quick hint - and one which applies to other patches
> as well - would be for you to be trying multiple candidate passwords in
> parallel.

OK, thanks for the hint. And you are right, now I see that Domino code
can be sped up by slightly changing the algorithm (besides trying
multiple passwords). I'll do my best.

Still, 23% speed up just because of -march=pentium4 - is it natural?

I even tried SSE intrinsics as a replacement for 4x4 bytes memcpy,
memcmp and xor-ing, but it turned out to be... slower. Now I'll try some
SSE to parallel multiple passwords.

> Among those "things" is the need to pass weird options to recent
> versions of gcc to get decent performance of DES-based hashes on Alpha

Aha, I see. Well, good to know. From what I see in 1.7's Makefile you
are not embedding inline-limit nor inline-unit-growth. Do I understand
correctly that this makes Alpha binaries build from default Makefile
little bit crippled/slow?


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