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From: Yannick Gingras <ygingras@ygingras.net>
To: secprog@securityfocus.com
Subject: Re: Secure Sofware Key
Date: Tue, 3 Sep 2002 21:03:40 -0400
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> > Is the use of "trusted hardware" really worth it ?
>
> Answering that requires fairly complete knowledge of the business
> model. But, in all probability: no, it isn't usually worth it. So, it
> comes down to how difficult you want to make the cracker's job.
>
> > Look at the DVDs.
>
> IIRC, CSS was cracked by reverse-engineering a software player; and
> one where the developers forgot to encrypt the decryption key at that.

This make me wonder about the relative protection of smart cards.  They have 
an internal procession unit around 4MHz.  Can we consider them as trusted 
hardware ?  The ability to ship smart cards periodicaly uppon cashing of a 
monthly subscription fee would not raise too much the cost of "renting" the 
system.  Smart card do their own self encryption.  Can they be used to 
decrypt data needed by the system ?  The input of the system could me mangled 
and the would keep a reference of how long it was in service.

This sounds really feasible but I may be totaly wrong.  I may also be wrong 
about the safety of a smart card.  

What do you think ?

-- 
Yannick Gingras
Coder for OBB : Oceangoing Bared Bonanza
http://OpenBeatBox.org


