I’ve heard the latest Security Now, regarding the debate between Dave Marsh and Peter Guttman on DRM in Windows Vista. While a few good points were made, the major one - in my opinion - was not.
DRM, in a practical sense, is deeply flawed: The idea is to give you your media
- say, a WMA piece of music - and a program to play it with - say, Windows Media Player - but encrypt the media. Now, naturally, Media Player will need the decryption key for the media, and the idea is that Media Player will verify that you are allowed to listen to the song, and only then decrypt it - as it is played.
However, something is clearly wrong here - both the encrypted media and the decryption key are sitting locally on your computer. It’s like giving you a locked box, as well as a butler (which will live in your house, where you presumably have a shotgun) with the key, and telling the butler not to open the box for anyone unauthorized. That is, you can open the Windows Media Player executable with your favorite hex editor, and dig away for the key. This is, of course, very complicated to do - but there are advanced ways of finding these keys, and once they’re found - they’re out. That’s why we keep hearing about WMA and iTunes’ equivalent format being cracked every once in a while, when they change it. No matter how sophisticated the DRM, you still get both the locked box and the key. They might build bigger butlers, but we can build deadlier shotguns. (Sorry for the violent analogy, but DRM kinda does that to me ;))
So, what can the *AA/Microsoft/Apple/DRM scapegoats inc. do about this? Well, they could supposedly have Windows recognize that you are trying to view the Windows Media Player executable, and stop you (I’d be surprised if they haven’t done this yet). However, currently you can still, for example, run Linux on the computer, and use that to view the executable. And if, by some crazy coincidence, all variants of Linux stop you from viewing the executable - you can pick your favorite, change the source code so it doesn’t, and use that. To stop you from running whatever unprotected operating system you want, changes to the hardware must be made.
This is exactly what worries me about Vista. For the first time, we are seeing major effects like HDMI/HDCP, where the operating system interacts with the hardware directly to figure out exactly what the user is or isn’t allowed to do. Also, Vista boasts the “Trustworthy Computing” project, which is all too reminiscent of “Trusted Computing” - a project in which, through integrating protection from the bottom of the hardware (with a TPM, Trusted Platform Module chip) to the top of the software, the computer verifies that it is only running authorized operating systems, which run only authorized programs.
Now, the media companies would love this. Say HD-DVD’s been completely cracked, and an alternative, open-source, unprotected player has been released. If your system is TPM-protected, it simply won’t allow this software to run. Your own compiled applications can be forbidden from running as well, seeing as their source code just might be the HD-DVD cracking code. Unauthorized operating systems would, naturally, not be allowed to run.
Now, I’m not explicitly blaming Microsoft for this. Fact of the matter is, the protection they’ve built into Vista, although probably (for the reasons I’ve mentioned) insufficient, was required by the media companies in order for HD-DVD support to be (legally/technically) possible in Vista. Would Microsoft go so far as to enable the horror scenario I’ve pictured above? Probably not. But I do believe we all need to be aware of the risks, just to be on the safe side.