From: "Perry E. Metzger" <pmetzger@lehman.com>
Date: Thu, 15 Jul 93 07:05:31 PDT
To: cypherpunks@toad.com
Subject: Re: xor data hiding?
In-Reply-To: <9307150536.AA03891@triton.unm.edu>
Message-ID: <9307151405.AA05028@snark.shearson.com>
MIME-Version: 1.0
Content-Type: text/plain



J. Michael Diehl <mdiehl@triton.unm.edu> says:
> According to Perry E. Metzger:
> > J. Michael Diehl <mdiehl@triton.unm.edu> says:
> > > According to Douglas Sinclair:
> > > The point wasn't to be unbreakably secure; it was to be UNFINDABLY
> > > secure.  We convolute an allready encrypted message to the point of
> > > not being recognizable as cyphertext, then we hide it on the end of
> > > a file.  We want it to look like garbage.
> > 
> > Cyphertext from any decent system ALREADY looks random. Whats the
> > point of doing more to it?
> 
> Many encryption tools such as ripem, pgp, and dolphin can recognize their own
> output...which indicates that there is a footprint to that particular
> implimentation.

Intentionally. They INTENTIONALLY put magic numbers at the head of the
file. If you remove that, the file is random. You can hack PGP not to
use headers if you really want to. Proposing some useless cryptosystem
just to hide the headers is completely unneeded.

Perry