AACS Hack Blamed on Bad Player Implementation

seriouslywtf writes "The AACS LA, those responsible for the AACS protection used by HD DVD and Blu-ray, has issued a statement claiming that AACS has not been compromised. Instead, they blame the implementation of AACS on specific players and claim that the makers of those players should follow the Compliance and Robustness Rules. 'It's not us, it's them!' This, however, does not appear to be the entire truth. From the Ars Technica article: 'This is an curious accusation because, according to the AACS documentation reviewed by Ars Technica, the AACS specification does not, in fact, account for this attack vector. ... We believe the AACS LA may be able to stop this particular hack. While little is truly known about how effective the key revocation system in AACS is, in theory it should be possible for the AACS LA to identify the players responsible for the breach and prevent later pressings of discs from playing back on those players until they are updated. As such, if the hole can be patched in the players, the leak of volume keys could be limited to essentially what is already on the market. That is, until another hole is found.'"

Comments

Re:To be expected

[MoxFulder]

I wonder what they're going to say when it's brutally apparent that ALL software players can be compromised.

In my mind, we're already there :-) The logical next step is to allow only hardware and partial-hardware players. For a PC, this would mean having some kind of "trusted" chip on your motherboard which can encrypt and decrypt data using keys that are hard-wired in.

Of course, hardware solutions can be broken too. I can envision a couple of ways this will happen:

• If the keys are truly embedded in the "trusted" ASIC: Making custom chips is expensive. There are substantial setup costs for each new mask, so there will be enormous economic pressure to only have one or a few versions of the chip. This means once one version gets cracked, millions of computers will be freed. What will it take to read the keys off an ASIC? A scanning electron microscope, that's what. As a bored physics grad student currently sitting 10 feet away from an SEM, I can tell you it'll happen :-)
  
• If the keys are somehow individualized to each computer, they'll be stored on a flash-based FPGA, or in some kind of microcontroller's flash memory. Manufacturers of such flash-based devices go to great lengths to make it so that the code stored in flash can't be read off of the device, but this is nothing more than the same ol, same ol security through obscurity... figure out the magic voltage that you need to apply to pin 12, and oops there goes the security. Smart card hackers have already figured out ways around the protection in the common PIC16C84 microcontroller.
  

Bottom line: DRM is futile because it requires the distribution of a SECRET PIECE OF DATA (the decryption keys) in UNENCRYPTED form (the keys themselves must of necessity be unencrypted). All the crap interposed between the user and the keys is merely security through obscurity. QED.