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HD-DVD and Blu-Ray Protections Fully Broken
Posted by
Zonk
on Tue Feb 13, 2007 01:12 PM
from the open-season dept.
from the open-season dept.
gEvil (beta) writes "According to an article at BoingBoing, the processing keys for the AACS encryption scheme used by both HD-DVD and Blu-Ray video discs have been extracted, and a crack has been released. What this means is that there is now a method to extract the copy-protected content of any HD-DVD or Blu-Ray disc out there. This is different from Muslix64's previous crack, which only extracted the volume key for each disc. This new method bypasses this step and allows anyone to extract the data without first requiring the volume key."
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IT: AACS Cracked Again 306 comments
EmTeedee sends us to a blog post for a summary of the latest results in cracking AACS, from the Doom9 forums (as the earlier cracks have been) — after the DVD Security Group said it had patched the previous flaws. From the DLTV blog: "This time the target was the Xbox 360 HD DVD add on. Geremia on Doom9 forums has started a thread on how he has obtained the Volume ID without AACS authentication. With the aid of others like Arnezami they have managed to patch the Xbox 360 HD DVD add on... It appears that XT5 has released [an] application that allows the Volume ID to be read without the need to rewrite the firmware. This would mean that anyone could simply plug in the HD DVD drive and obtain the Volume ID from any HD DVD without the hassle of flashing it."
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Nice. (Score:5, Funny)
Re:Nice. (Score:5, Funny)
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Re:Nice. (Score:5, Funny)
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Re:Nice. (Score:5, Funny)
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Re:Nice. (Score:5, Funny)
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Re:Nice. (Score:5, Funny)
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Re:Nice. (Score:5, Informative)
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OK, time to switch now! (Score:5, Insightful)
DVD-JON (Score:5, Funny)
Re:DVD-JON (Score:5, Funny)
What?
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drm (Score:5, Funny)
Re:drm (Score:5, Funny)
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props to Muslix64 and hackers everywhere (Score:5, Insightful)
Vista Help Forum [vistahelpforum.com]
Re:props to Muslix64 and hackers everywhere (Score:5, Insightful)
It has always been easier to destroy/crack something than to create it in the first place.
It is not a great undertaking to break a DRM scheme. It is not comparable to cracking strong encryption (which takes lots of horse power). The basic concept of DRM is fundamentally flawed and therefore open to attack.
DRM by its nature is both widely available and has to function on a user's local device or PC. The wide availability (unlike an encrypted message with a unique key) means the attacker has easy access both the algorithm and protected content. This mathematically greatly reduces uniqueness. One only has to setup the correct environment and observe how it functions with a legal copy. And since the DRM scheme is most likely non-unique on a copy by copy basis the affect instantly cascades. Unlike getting a randomly encrypted file you have access to the algorithm (the software) and you have access to the keys.
The big issue in DRM is how to obfuscate your algorithm and how to keep people from getting access to the stream in the clear. Both of these tasks are next to impossible to carry out effectively.
So anyone, even the very same "small group of unpaid media hackers" in question, would have to spend a large amount of effort trying to come up with better and better obfuscation schemes. While cracking the DRM will take far less resources, focus, or time.
Cracking DRM is more akin to white box QA or reverse engineering.
All that said I'm secretly glad someone stepped up and did this
I'm willing to bet 5 years from now we will see far less DRM in use and those still using it won't be selling as much music or as many movies as those not using it.
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Re:props to Muslix64 and hackers everywhere (Score:5, Informative)
That said, they have got a player key now, so all disks published to date can be decoded.
Each player has its own player key, and each disk accepts any player key in its list (the player key is used to decode the volume key which decodes the film).
With this player key, they can decode any HD-DVD which has been printed already. However, as the key has now been compromised, future disks will not accept that player key. The software will have its player key updated, but the software will be tightened in an attempt to remove this loophole.
Take a look at the archives of http://www.freedom-to-tinker.com/ [freedom-to-tinker.com] for a detailed discussion.
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All DRM implementations will be broken. (Score:5, Insightful)
In effect, DRM is security through obscurity.
How much longer will we have to put up with this crap before the media companies realise this and stop inconveniencing their customers and wasting our money and time as well as their own?
Re:All DRM implementations will be broken. (Score:5, Informative)
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Re:All DRM implementations will be broken. (Score:5, Insightful)
Forget all that jibber-jabber about whether they have a right to protect their "copyrights", or even if you have any rights to copy: they clearly cannot be trusted with your secrecy and your privacy.
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Re:All DRM implementations will be broken. (Score:5, Insightful)
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Re:All DRM implementations will be broken. (Score:5, Funny)
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Re:All DRM implementations will be broken. (Score:5, Funny)
Or things could go in the opposite direction. Just wait 'till they hear about one-time pads!
Of course, that would mean that no one could watch their stuff, period, but hey - at least no one could pirate it either!
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Re:All DRM implementations will be broken. (Score:5, Funny)
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For as long as... (Score:5, Funny)
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Re:All DRM implementations will be broken. (Score:5, Informative)
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I disagree (Score:5, Insightful)
I'm not saying that this isn't a nice event, but we have further work to do.
Re:I disagree (Score:5, Interesting)
The same method used to acquire this key can be used to acquire future keys. All it takes is one determined hacker willing to rifle through his memory addresses for the key.
I do not see a terribly effective fix for this - your key has to exist somewhere, and even in a CPU register it is still in memory more often than not.
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Nope, it's really cracked (Score:5, Insightful)
In theory yes, but how easy do you believe it is to update all those specialized video players, all offline?
Don't forget: the people who buy those already had to put up with paying premium for a HDTV, expensive players, and also make sure the TV, cable and player play together through HDMI.
If you start demanding they are hooked non-stop to Internet so they can receive the daily patches, it may just be the thing crossing the line of tolerance.
Also: the hard part is retrieving keys from pure hardware. The new keys come as firmware updates over the network.. it's even easier to update those HD-DVD/BlueRay rippers. After all, you have even the keys they encrypted the patches with: you have the player, don't you.
All in all, the "super morphing update" ability of AACS seems more like a way for the AACS developers to claim "the war it's not over", when it effectively is over.
Companies will refuse to use the new keys for their disks, since they will be incompatible with plenty of the players out there, the AACS creators will whine a bit about how "they could fix it but they don't wanna, not our fault", and this is where it'll end.
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Too funny... (Score:5, Insightful)
As soon as you can see or hear it, it is then possible to duplicate it. No amount of copy protection will ever be able to prevent that short of preventing consumers from accessing the material altogether.
Learn to trust your consumers a little and focus on adding value to the material, and then people will buy your content. It might also help to provide some flexibility in the content licensing model, maybe giving people the option to upgrade DVD discs to HD-DVD for the same content may encourage them to continue buying media.
Can this be fixed? (Score:5, Interesting)
Re:Yes, someone walk us through this. (Score:5, Insightful)
Poking around Doom9 thread [doom9.org], the processing key for all current HD-DVD discs was found.
Looking over some example source code [doom9.org], the processing key is used with the encrypted C value to build the media key, which can then build the volume key, which can then decrypt the disc.
The MPAA can revoke the processing key, but quoting from the forum:
Some of you are missing the true meaning of this compromise. If they revoke this processing key, we just take a player compatible with a new processing key, put in one of the titles that's already cracked, and go around in memory looking for the known key. We find it, insert a new title, look in the same place and we have a new processing key.
Essentially, it becomes a known-plaintext attack.
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Doom9's Forum (Score:5, Informative)
Later posts seem to confirm that it works for both BR and HD-DVD
industry's response? (Score:5, Interesting)
Re:industry's response? (Score:5, Insightful)
Lawyers, I guess.
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Released Too Early (Score:5, Insightful)
Re:Released Too Early (Score:5, Insightful)
The premise that all consumers are criminals is criminal in and of itself. Bear with me here. It defies logic and law to (analogy time) remove guns from citizens to prevent them from shooting people. It defies logic and good business sense to make
Besides this, governments should not be propping up business models that are antiquated and broken. Desktop publishing put typesetters out of work, did the governments do anything? Trains put buggy makers out of work, did the governments do anything? That is only naming a couple of examples, but the governments seem hell bent on protecting certain industries. I can only conclude that those same governments are being well paid by those industries, for that is the only logical motivation for such infringements on citizen's liberties and rights.
Now that AACS is cracked, time to follow the money and figure out who is getting paid and expose them as broadly as the DRM keys are exposed.
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The inherent problem... (Score:5, Insightful)
Until vastly different technology is available 20 or 30 years down the road, all that DRM is going to amount to doing is preventing the 'average joe' from copying en-mass. They just have to make it difficult enough for the casual user to be deterred from copying the content. Look at the copy protection scheme on the iPod - it's basically useless, but it prevents grandma from copying bulk amounts on content. It's like how photocopiers are not a danger to printed media, as it's just 'too' difficult to walk up to a copier and copy things on mass. The industry just has to make it hard enough to deter joe user.
The real problem for the recording industry comes in when now people are getting more and more saavy at copying content, and it's becoming more and more common place, and digital media sharing is now common place and digital media is now common place in the living room now. 10 years ago MP3's were just making there way on the scene and basically only very saavy users knew what an MP3 was, let alone what to do with it. What happens when 10 years from now mobile HD video players are just as common as MP3 players, and your average iPod video has a half a TB of flash storage? Copying (High-Def) DVD's at that point will be common place like MP3's are relatively common place now.
In response (Score:5, Funny)
New DRM protection methods are now in the works which were cracked last week.
Not Really Broken (Score:5, Informative)
One key thing to take away from this is that the authors of the software made it really easy to pull the device keys out of memory for two reasons
- They kept them in variables that were physically near the variables for the volume key
- They zero-ed them out after use, leaving big gaping holes of zeros in memory in a place where that kind of looked funny, drawing attention to those areas
If they are smart (and if the MPAA even give them another chance), the powerdvd/windvd authors will reimplement their AACS decryption code to never store the keys in memory. Without double-checking, I believe the keys are only 128 bits, they could be loaded into the SSE registers in encrypted form and then decrypted on chip. The authors will still need to take measures to prevent an OS context switch from storing the registers in kernel-private memory during the period in which the device keys are present, but that is not an extended period of time, presumably they can kick their priority up high enough that it won't happen without hurting the system much.Even that approach isn't hack-proof, but it is a lot harder to dump the cpu registers under such conditions than it is to trace memory accesses.
Re:Not Really Broken (Score:5, Interesting)
Good thing Intel put in those nice debugging registers that let you dump the contents of SSE registers at arbitrary intervals (e.g. after every SSE operation by the debugged process).
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Re:Not Really Broken (Score:5, Informative)
You've clearly never worked with a good hardware-assisted debugger. And virtualization makes this scenario possible without debugger hardware support.
Even more, no matter what, the key has to make its way from the device to the CPU register. On every modern machine that transaction goes through memory. Which means that brute-force tracing from the device to the registers should be able to find it. Not necessarily easily, but quite doable.
DRM is dead. Let's bury it.
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Re:Not Really Broken (Score:5, Informative)
Under most versions of unix, only one debugger can attach to a process at a time. So an easy trick to prevent being debugged is to make the program attach to itself, thus locking out other debuggers. Some unices don't let a process attach to itself, but for those it may be possible to fork a child and have each process mutually debug the other. I'm not an NT programmer, but I would bet something along those lines works the same there too.
Don't get me wrong, nothing is fool-proof (and I said so in my first post) the best these guys can do is make it difficult. So far, the windvd/powerdvd guys just wiped the device key from memory after use which is about the bare minimum - they could have done lots more without too much effort.
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joke is on us (Score:5, Insightful)
why laugh at them when you can steal their money?
we need a committee of slashdot readers to compile a list of buzzwords and concerns of the RIAA/ MPAA, and then sell them some technovoodoo that doesn't protect them in any way whatsoever (nothing can, obviously), but continues the RIAA's/ MPAA's illusion that drm can or ever will work
give them their false security blanket, steal their money outright, and then continue to rip them off and drive into extinction the antiquated notion of corporate media distribution channel ownership
they need us, we don't need them. make that point explicit by bleeding them dry via all possible avenues
win win! idiots
look at book publishers... (Score:5, Insightful)
I think the recording and motion picture industries need to look at why, and follow that lead. Instead of millions in copy protection R&D, why not spend millions to improve the product? Make the product something people liked owning. (Notice how libophiles obsess over the actual tangible book?).
The one really viable way to control it would be to mandate that all players have an internet connection and it verify the purchaser has rights to the media before playing it. Of course if people have good high speed connections to the internet there's no reason to buy the physical media, which they recording and motion picture industries simply can't abide with.
Here we go again... (Score:5, Interesting)
And because of that, when I put my iPod shuffle through the wash I was able to replace it with a good AAC-playing MP3 phone and flip the bird to Steve Jobs. Same thing with these...I want my media in formats I can move around and use to my liking.
I'm not going to pay for the same content twice, ever. And if I can't get my content in a cracked DRM or DRM-free format, I'll just pirate it. That'll show 'em.
Success! (Score:5, Funny)
arms race (Score:5, Interesting)
First, making the volume information secure, and file content, was pretty pointless because if you had strong security on it, it would be too slow to do anything useful. For the data, you could wait longer, but at the end of the day, all of it was moot because once either catalog or data is decrypted... its there. So, you decrypt on the fly, or use adaptive methods that attempt to hide information, it all leads to...
The Cost of protection geometrically increases to the linear Time to break it.
And in the end, all the protection does is buy you a little bit of time, because for every couple of guys thinking up the next best protection scheme, once it hits the world, you have 100+* the resources trying to break it.
In the end, the best protection we came up with was something everyone hates... a hardware key that imlpemented the decryption, and sell that key with the media. Economically not viable to copy, but still does nothing once unprotected.
No different than us web developers (Score:5, Insightful)
I can't help but see this as a parent who is all too restrictive with thier child, leading the child into endless rebelion that would have been avoided if moderation was used instead of a billy club.
Re:Now we get to see... (Score:5, Interesting)
Revoking keys would have a huge negative impact on the adoption of HD-DVD and Blue-Ray. Look at the backlash from the Sony rootkit -- that was something a lot of consumers were/are unaware of. It's harder to be unaware of the fact that your $900 dvd player no longer works, or your $2000 HDTV doesn't work. The inevitable lawsuits aren't worth it.
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Re:Now we get to see... (Score:5, Interesting)
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Re:Horseshoe racket (Score:5, Insightful)
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