From: Steve Reid <root@edmweb.com>
Date: Sun, 30 Jun 1996 15:08:49 +0800
To: Andrew.Tridgell@anu.edu.au
Subject: Re: rsync and md4
In-Reply-To: <96Jun30.105019+1000est.65036-6357+785@arvidsjaur.anu.edu.au>
Message-ID: <Pine.BSF.3.91.960629200514.626A-100000@bitbucket.edmweb.com>
MIME-Version: 1.0
Content-Type: text/plain


> > MD4 is not strong- people can deliberately produce files with the same
> > hash in a matter of minutes. MD5 is secure for now, but it seems to be
> > gradually falling to cryptanalysis, and should be phased out of use before
> > it breaks. IMO the best hash algorithm is SHA1 (which is an updated
> > version of the original SHA). Do a web search for "FIPS PUB 180-1" for the
> > specs. 
> 
> Do you have references to the md4 collision stuff? The situation I
> have is a bit unusual so its just possible some of the results may
> apply. 

Sorry, I was actually thinking of two-pass Snerfu that can be collided in
a matter of minutes... I'm fairly certain that MD4 is collidable, but I
don't remember where I read that, and I'm not sure how much time it would
take.

I'm quite certain that MD4 will not collide by accident, so it would 
probably be okay for you.


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