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From: Jason Thorpe <thorpej@shagadelic.org>
Date: Fri, 4 Mar 2005 11:23:36 -0800
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Subject: Re: FUD about CGD and GBDE  
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On Mar 2, 2005, at 4:33 PM, ALeine wrote:

> You need 2^128 steps to break the encryption of a single sector.
> But you have no idea which of the 2^128 sectors is the right one,

You may not know "for sure", but you can make a pretty well educated 
guess.  You are basically ignoring Roland's argument that disks are 
well-structured.

Start by looking for the MBR partition map / disklabel / GPT.  Those 
are kept in well-known places, so you can greatly narrow your search 
space.  Use the info contained therein to find likely superblock 
locations.  Etc.  You do not have to brute-force the entire disk.  You 
just have to be smart about how you search.

-- thorpej