Re: Necessity for device overwriting?

Phil Grundig <[email protected]> Mon, 25 May 2009 11:07:44 +0000 (GMT)
Newsgroups gmane.linux.cryptography,gmane.spam.detected
Message-ID <[email protected]>
> > Can an attacker discern the size of individual files if the device has not

> > been overwritten first?
> 
> It´s a practical approach to give you a better understanding. Try less -f 
> /dev/sdX on the device you are going to encrypt. A blank block device is filled 
> with zeros or continually the same single character. Issuing shred /dev/sdX 
> shows strong resemblance to what loop-aes encryption leaves behind.
> In case only a first fraction of a block device is filled with such random 
> (looking) data one might suggest you to reveal keys/passes to uncover the real 
> nature of this information. In case you find a method of storing data using just 
> one character please inform me as soon as possible ;-)

Ok so you're saying it is about plausible deniability concerning the likelihood of there being encrypted data there, not about trying to uncover anything actually usable about the encrypted plaintext.   


      

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