Building the AACS Next-Gen Copy Protection Scheme

Anonymous Slashdotter writes "The IEEE Spectrum has a piece that discusses the proposed encryption scheme for the upcoming HD-DVD standard. 'The key to the spirit of compromise is an agreement that the AACS specification will allow consumers to move the data on an optical disc to the various devices they own, including video servers and portable video players, either directly or via a home network.' AACS will use a so-called strong key, the 128-bit Advanced Encryption Standard approved by the U.S. National Institute of Standards and Technology."

Comments

So compromised keys make for faulty hardware?

[pegr]

According to the article, a compromised key will be dropped so that device will no longer be able to decode new content. So the vendor has to explain to his customer why his product doesn't work anymore, likely through no fault of his own? Yeah, that'll fly...

Re:So compromised keys make for faulty hardware?

[grub]

I was wondering how they industry would know what player it was that was compromised. Sounds like a bunch of suits have been sold some snake oil.

Re:So compromised keys make for faulty hardware?

[silicon-pyro]

Agreed. From TFA:
The basic idea in recovering from cracking is to make a compromised player key obsolete. Compromised players could continue to play old discs, but not new releases. And crackers would have to start all over again.

Consumers are really going to be interested in continuously buying new players or upgrading their current firmware to play new realeases because someone broke through their brand of player. Save for the fact that once someone breaks it once, it will just get easier to do it the second time.

I can see how this would solve the cracking problem entirely. Consumers have the money, thus, consumers have the power. The simple fact is, people won't buy a disc that won't play in their player -- At least I'm not about to new player to play their new disc every time this happens.

In case they think up some scheme that means I won't have to pay anything for the upgraded player: my time is as valuable to me as money, so I had also better not have to spend any of that on getting my machine to work again either.

Re:So compromised keys make for faulty hardware?

[rincebrain]

And just like DVDs today, all it takes is a decent amount of time and effort, and suddenly the keys you thought were secure are now being used to playback content under Linux.

Re:So compromised keys make for faulty hardware?

[tomstdenis]

sounds like?

First indication was the word [well acronym] "DRM". Just because it uses AES doesn't mean it's secure. It's very easy to use AES insecurely [hint: constant key in ECB mode...]

Likely another 17 yr old from some europe'like nation will break this and "deacss" tools will appear on the net.

Why don't the media producers focus on more talent and less "blockbuster stars".

Instead of paying one star 20 million for a picture why not pay 200 actors 100,000 for several movies? Duh cuz that would make sense...[well not for the self-centered power-tripping millionaire fake people].

Tom

Re:So compromised keys make for faulty hardware?

[k12linux]

Consumers are really going to be interested in continuously buying new players or upgrading their current firmware to play new realeases because someone broke through their brand of player.

This all seems like a set-up to me.

1. Consumers buy scads of DVD equipment without knowing a compromized key will disable their player.
2. Keys start to be cracked.
3. Industry tells upset consumers that the reason they have to buy new equipment is evil cracker (not poor design/planning.)
4. Consumers buy new equipment and demand that something be done to prevent this from happening again.
5. MPAA and others get new super-DMCA laws passed.
6. Attempting to watch a DVD on Linux is now punishable by death. (At least in Texas.)

Yeah, I can see how the consumer wins in that scenario.

Re:So compromised keys make for faulty hardware?

[Wesley Felter]

But that doesn't make sense. How can the content key be encrypted with (e.g.) 100 million different player keys?

Re:So compromised keys make for faulty hardware?

[jokell82]

A more likely scenario:

1. Consumers buy scads of DVD equipment without knowing a compromized key will disable their player.
   
2. Keys start to be cracked.
   
3. Industry tells upset consumers that the reason they have to buy new equipment is evil cracker (not poor design/planning).
   
4. Consumers don't understand what the industry says, just know that their latest Toshitsu DVD player wont play Buddy Cop Movie #83
   
5. Consumers attempt to bring back their properly working DVD players only to be told they can't return them
   
6. Consumers attempt to bring back their properly working copy of Buddy Cop Movie #83 only to be told they can't return it
   
7. Consumers get pissed and either (a) stop buying movies or (b) buy another player (I'm betting b)
   
8. Consumers go about their lives not caring about what laws are passed, just as long as Buddy Cop Move #83 plays on their TV.
   
9. MPAA and others get new super-DMCA laws passed just because they can and have the money to do so.
   

Man, really makes you look forward to HD-DVDs, don't it?

Re:So compromised keys make for faulty hardware?

[tacokill]

"Instead of paying one star 20 million for a picture why not pay 200 actors 100,000 for several movies"

Ok, you do that. And I'll pay 199 actors $101,000 for several movies. And then my competitor (and yours) will pay 198 actors $102,000 -- wash, rinse, repeat. Guess who is going to get the better actors over the long run? The guy who pays the most. Welcome to capitalism. Now go enroll in Econ 101 so you can follow this out yourself. It's important, trust me.

Re:So compromised keys make for faulty hardware?

[tomstdenis]

Because they're shallow and "don't know what real talent is" [as Weird Al would put it].

Personally what I look for in a movie is depth. Superficially weak dialog [re: 99% of TV shit] annoys the hell out of me, even if it's someone of super-star status like Keano, whoa.

So if you take some "no-name" talented actor and put them in a movie with some real depth to it [even if it's a comedy] then people should be able to enjoy the experience.

I mean, you can't honestly tell me you saw any of the Matrix movies for anything more than the special effects. The story is very weak about as a deep as a Crest toothpaste commercial.

Tom

Re:So compromised keys make for faulty hardware?

[Sebastopol]

Instead of paying one star 20 million for a picture why not pay 200 actors 100,000 for several movies? Duh cuz that would make sense...[well not for the self-centered power-tripping millionaire fake people].

Bingo! I like your style. In a perfect world, the market decides the $$$ worth of a job, and I think we all can agree than John Travolta, Collin Farell, Hillary Duff, Sandra Bullock, Jeniffer Aniston and all those other frauds deserve a big fat realty bitch-slap.

Philip Dick lived in poverty and ate fvcking dogfood when writing so that idiots like Tom Cruise and Ah-nuld could make millions off of PKD's plots.

Re:So compromised keys make for faulty hardware?

[tomstdenis]

If I can't goto a local theater [note: there is an indy theater downtown ottawa on Rideau street for the tourists out there] or rental place [none in Kanata, outside of Ottawa] that has indy films, I won't see indy films.

If stupid 10x larger blockbusters didn't overshadow [in terms of mindspace via advertising] the indy films they wouldn't do as well.

Tom

Re:So compromised keys make for faulty hardware?

[Tenebrious1]

Consumers get pissed and either (a) stop buying movies or (b) buy another player (I'm betting b)

(c) Consumers hear from friends that Buddy Cop Movie #83 can be downloaded from the intarweb, and join the P2P masses. Vow never to pay for another physical DVD again.

Re:So compromised keys make for faulty hardware?

[chris_mahan]

That's because all movies are the same price. Imagine three restaurants: A fast food chain, texas steakhouse, and sushi restaurant. Now, in all three, the meal is $9.99. Where do you go? Mmmm? Where the food is better (pick sushi or steak).

If Jack Nicholson, Robin Williams and Nichole Kidman in a "verysexy" scene movie was $60 and the third remake of "I was a nut" by 5 poorly paid actors was $4, then, some people would spring for the talent, and the masses would go fo the $4 movie.

But if enough went to the $60, they would be able to pay JN, RW and NK 20 mil each. And I guess you'd really have a killer movie.

It happens in DVD sales. Really good movies with good actors never dip below the $20 mark. the crappy stuff falls to 7.99.

The movie theatres are at fault here. They should demand-price the movies.

Re:So compromised keys make for faulty hardware?

[ecki]

Take a look at CPRM, AACS is quite similar.

Re:So compromised keys make for faulty hardware?

[tchuladdiass]

In theory, this is simple. You have an encryption algorithm set up as follows:
The data is encrypted using key "A", but can be decrypted with key "B" (similar to RSA). However, in this case "B" is computed via a function that has inputs "A" and "C", where "C" can be an one of a very large keyspace. And, "A" can't be determined by "B". This allows you to have a unique "B" decryption key for every player.
In other words, you have:
* encrypt(A)
* decrypt(B)
* B = hash_of (A, C), for any valid value of C
* C = one out of a large keyspace (allows unique B for each unit)
* A cant be determined by B

Since key A isn't on the individual units, it is as secure as the manufacture's internal security policy (so it isn't likely to be compromised). And the decryption key B is unique for each player.

Now, I don't know of any methods that can produce the above results, or if this is what AACS uses, but I don't see it being impossible either (just like asymetric encryption wasn't do-able until RSA came along).

Re:So compromised keys make for faulty hardware?

[snorklewacker]

PKD's estate gets a dumptruck of cash backed up to it, courtesy of the residuals he gets from optioning his stories. If the movies didn't have the megastars, it's quite possible they might not have had the success enough to get him the cash.

Megastars exist for somewhat similar reasons as pop stars: the audience's familiarity with performance, and better, their desire to see more of it, is more or less a consistent factor. Some people like Tom Cruise (I thought he was great in Collateral, though I rather dislike him otherwise), so they're more inclined to see his movies. This makes them a safer bet, and safe bets are what you want when you're spending eight figures on a movie. Maybe we need more movies with a few less zeros in their budget, but some genres are just expensive in general (Lord of the Rings would have sucked on a shoestring budget)

Yeah, I think they should open up the auditions to lesser-known actors, since there's always a chance that one could just dazzle the director, but it's not quite as cynical a process as you think. Nor is acting just standing up there and saying your lines with face and voice written on the script. If you think it's that easy, try it yourself. I can't easily explain the success of Jennifer Lopez in movies (i.e. how she managed to get into more than 2), but there's a damn good reason the likes of Anthony Hopkins and Denzel Washington are in such demand.

Re:So compromised keys make for faulty hardware?

[mattyrobinson69]

and all it would take for that is somebody to work out how the key dvd's work, infact taht would probebly be better in the long run

Re:So compromised keys make for faulty hardware?

[Sebastopol]

...have had the success enough to get him the cash.

PKD died before his first movie was optioned. My point still stands.

You cannot possibly argue that Brad Pitt's salary is justified compared to say, a teacher or a garbage man. (Pull your kids out of school or don't empty your garbage for a week and see what I mean).

Are Hopkins and Washington your idea of good actors? That point means two different things depending.

I'm a cinema snob, I admit it. And I laugh at how people on this board (not you) claim to be all counterculture with their OSX and Linux flavors, but then bow to the Microsoft version of cinema that lives in the hollywood blockbuster.

Re:So compromised keys make for faulty hardware?

[dgatwood]

Even if such a thing were mathematically possible, constructing an alternate A such that one particular B fails without breaking any other arbitrary B would likely be computationally almost impossible.

My guess is that the "key" is little more than a hardware serial number, that the decoder is a program on the disc that uses a fixed decryption key, also on the disc, and that the program includes a list of "keys" (serial numbers) on which it should refuse to play.

Even with such a scheme, though, it could be broken by:

• A. reversing the algorithm used to detect whether a s/n is valid (which isn't usually that hard once you figure out how the code that verifies it works), thus allowing Linux to randomly pick a different key for each playback if desired within the entire potential key space
• B. altering the program in-flight to remove the stolen key from the rejection list (also probably easy unless the list is encrypted, and even then, the key has to be on the disc somewhere unless it's based on a common hardware key, in which case you're back to the original DVD situation which still wasn't hard to break)
• C. simply reading the decryption key and using a standard AES algorithm to decrypt the contents instead of the program.

Any mechanism in which you refuse to play if your hardware matches a particular key must either involve the hardware being trusted to verify its unique key against a list or must require the hardware to "phone home" to the MPAA and get the real decryption key based on its serial number. I don't see the public accepting either of these. "What do you mean I have to wait two whole minutes to start playing the DVD and I can't be on the phone?"

Long story short, the MPAA is being sold a lot of snake oil. It's too bad that they're too technologically clueless to realize it.

Re:So compromised keys make for faulty hardware?

[karnal]

Specially now that I'm done with college I have loads more free time. ;-)

No kidding. I count 24 posts from you today alone!!! :)

Re:So compromised keys make for faulty hardware?

[tomstdenis]

Why would they lie? They're responsible well-intentioned adults. Clearly they have a case.

Re:So compromised keys make for faulty hardware?

[eluusive]

Simple:

Disk is encrypted using private key A. Disk can be decoded using public key B.

Public key B is then encrypted using 100 million other keys and each version is saved in a different place on the disk. These encrypted versions of B are small and take up very little space.

When a player goes to play a disk, it looks for the key file for it's model, decodes it with the key it has in ROM and then uses the subsequent key to decode the movie.

This is absurd, as I and I anyone else will not buy new DVD players every time some hacker steals the key from the model we bought.

Re:So compromised keys make for faulty hardware?

[tacokill]

"limitless number of performers out there (typical econ fallacy)"

There are, in market terms, a limitless number of actors/actresses. Just judging by the number of people who "wanna make it", it's pretty easy to see that supply outweighs demands. This isn't just true for movies and plays, it seems to be true for ALL the fine arts. In fact, that's one of the reasons why we have starving artists. There's just so damn many artists out there.

Repeat after me: if you have a commodity skill set, you are NOT special. Just calling yourself an artist, actor, or whatever does not automatically mean you can command any price you want. I do not mean to lump all artisans into commodity status because there are many many fine standouts who DO have specialized skills. Commodity status refers to how the buyers perceive the market, not how sellers perceive themselves.

Regarding your comment that I know a lot about Econ, I don't. I know Econ 101. What scares me is that Econ 101 passes for "knowing a lot" in your book. Like I said, get yourself into an Econ 101 class and learn this stuff. It's important because it's HOW the world works. You can argue whether it SHOULD be that way but you are wasting your time because IT IS that way. Period. Now go learn about it...

Re:So compromised keys make for faulty hardware?

[silicon-pyro]

The individual key thing is too easy to break. Lets try and go through it.

One needs only break one of those keys and distribute it. Then all movies will be able to be read freely until that key is removed from the standard keyspace. This key may not be able to be gained from the disk itself, but manufacturing insiders would have access, and it may be able to be reverse engineered from the player ROM itself.

Considering how quickly a new rip propagates down the network, just think how quickly 128 bits of data could do it. For instance it could easily be stegged into an image or sound file, and distibuted right under the noses of onlookers. There would be some lag time between the key being available and the studios finding out about it.

Now wait until a guy gets his hands on ten of the "crackable" players. He gets ten unique keys, and now the problem is tenfold. Release a new key as soon as you see that the old one is no longer in use, and you're back in business.

The studios don't know which key has been cracked, they only know that one has. Unless they mark the content separately with the key in question, or a hash thereof, and try and get it back after the movie has been recommpressed. They couldn't disable a whole lot/brand/model of players for fear of a peasant uprising.

Compound this by the fact that it would be a recurring process, happening through multiple channels, and the pirates would have no trouble keeping ahead of the studios. The crackers stay a day ahead of the studios, and there is no control. The problem is that they would be weeks ahead at least.

I don't mean to promote these things. I have downloaded a movie or two before for a laugh, but it's not worth it in time and quality, and on top of it all it's illegal and immoral (to me anyway). Buy the DVD if the movie has the sticker value to you, leave it on the store shelf if it doesn't. I don't forsee myself having any problems in this key-per-unit scenario; My key will always work. I only don't understand why people waste their money on something so fruitless as DRM.

Re:So compromised keys make for faulty hardware?

[Jherek Carnelian]

Long story short, the MPAA is being sold a lot of snake oil. It's too bad that they're too technologically clueless to realize it.

Slight correction:

Long story short, the MPAA is being sold a lot of snake oil. We are very fortunate that they're too technologically clueless to realize it.

Heh...

[grub]

I can see the ads in the theaters already. "I'm John Weiner and I design ciphers for the movie industry. Downloading movies hurts me."

Re:Heh...

[TheGavster]

If he designs the ciphers, people cracking them is job security :) I don't think the guy with that job will ever design a good solution, even if it were possible.

Not that its really feasible to make an unbreakable encoding for movies. Allowing the user to have the player in their house is like giving the British an enigma machine encased in concrete during WW2; they can't immediately break your codes, but its not like they're going to refrain from cracking it out and using it.

Ladies And Gentlemen...

[rincebrain]

START YOUR CLUSTERS!

*makes sure his copies of john are all up to date*

May I ask a simple question?

[onemorechip]

Why is encryption necessary on a product that the user must be able to read in the first place?

What's next, encrypted books, newspapers, and magazines?

Re:May I ask a simple question?

[tepples]

What's next, encrypted books, newspapers, and magazines?

Stallman seemed to think so, eight years ago.

Distribution control

[Space cowboy]

The main flaw I can see in this is that as soon as it has been 'cracked' (which could be as simple as re-digitising the stream being sent to the video device), it can be reformatted into an MPEG2 / H264 stream and put onto BitTorrent. The simple fact is that it only needs to be broken *once*, and *everyone* can get it.

The movie business is going to hit the same wall as the audio business did, and the solution the audio business came up with (well, more accurately, were forced into) was to make the downloading of songs relatively cheap (under $1). As soon as it's not worth it to go through the hassle of copying the data, it is once again a viable product. At the moment, the movies are not viable products...

Simon.

Re:Distribution control

[Sexy Bern]

I assume you're in the US, but many, many of us aren't.

You have the luxury of (usually) having the first cinema screenings of films and the first releases to DVD. You also don't get the shitty $1 = £1 currency conversion that the media companies think is perfectly acceptable.

I personally don't think I'm getting value for money (£30) every time I take my wife and three kids to a cinema filled with chavs and twats that don't know where the "off" button is on their mobile phone.

It's not just about cost, but certainly outside the US the cost of films (either at the cinema or DVD purchase) is extortionate.

So I vote with my feet. I rarely go to the cinema and I wait until it comes out on rental. Three days' rental for £3.50 without said chavs is a bargain!

How is this gonna stop large scale piracy?

[slakdrgn]

I'm cerious on how (mabey I don't understand how they are made from the get-go) this is going to stop large scale counterfitting, those with access to machines that make perfect dupilcate copies, bit by bit, groove by groove, notch by notch. I can see how this will effect personal piracy, even mom-pop dvd rental places and possiable internet, but I thought counterfit was still a rather huge loss.

Mabey I'm wrong?

Re:How is this gonna stop large scale piracy?

[Ironsides]

I'm cerious on how (mabey I don't understand how they are made from the get-go) this is going to stop large scale counterfitting, those with access to machines that make perfect dupilcate copies, bit by bit, groove by groove, notch by notch.

It won't. There is nothing you can do to stop a copy like that unless they figure out how to put data on the disk in an area that can't be burned to (say like the disks serial number or information type on a CDR/RW or DVDR/RW). Even then, the proffesional piraters will probably still figure out a way since they use the EXACT SAME EQUIPMENT that hollywood uses to make their own disks.

Everyone re-encodes anyways.

[Anonymous Coward]

So all it takes is a DirectShow filter, frame capture to re-encoding program... what, it'll protect content for all of a week. Maybe?

Bah

[The Cisco Kid]

Unless I can extract the content to a non-encrypted format that I can play using non-proprietary software on stock hardware, it can go to hell.

Re:Bah

[Geoff-with-a-G]

And unless you're willing to pay them what they're asking for the product that they're selling, YOU can go to hell (as far as they're concerned).

If it comes down to MPAA vs. [the set of people who are unwilling to use closed, propreitary DRM systems], MPAA is gonna win.

They can live without the 3% of their market that's made up of hardcore nerds, but the nerds probably won't live without the 25% or more of their entertainment that comes from mainstream media distributors.

I want the same thing you want, but if you think you can just write them off, you're sadly mistaken.

Re:Bah

[timeOday]

For a good while this was the case with DVDs. I didn't buy one. Unfortunately it didn't seem to bother "them" one bit.

The only reason we can watch DVDs on Linux (and other OSS) today is due to some clever hacking that I'm sure was/would now be illegal under the DMCA. I thought it was purely a matter of recovering keys from a faulty player, but Andreas Bogk explains it was more complicated than that.

Unlike most people here, I think it's entirely possible the HD DVD standard will remain unbroken for a long time, though I hope I'm wrong. The fact that IEEE is having open discussions on how to do it right is unsettling. I'd rather the industry just assigned the job of designing HD DVD security to a couple lackeys and told them to have it done by next monday, that way it would certainly be flawed.

Re:Bah

[Skjellifetti]

They can live without the 3% of their market that's made up of hardcore nerds, but the nerds probably won't live without the 25% or more of their entertainment that comes from mainstream media distributors.

Then explain why Divx failed.

Feature?

[jacobcaz]

Isn't not being able to copy "Who's Your Daddy?" multiple times a feature and not a bug?

Copy protection my butt

[Roland Piquepaille]

The only thing they can hope to achieve is to make it harder to copy originals.

What I mean is, the problem isn't preventing people from copying a Blockbuster DVD, it's more a problem of preventing one guy, dedicated enough, from making a unencrypted copy and posting it on P2P. Once that's done, the cat's out of the bag and the copy-protection scheme will just annoy legit users. All the others will download the free copy.

So, what will happen is, when Joe Pirate wants to make a copy, instead of just sticking the disk in the drive and wait, he'll make himself some setup to capture the video from the DVD player and he'll re-encode the video. Added cost: a capture card and a cable. Period. And once the captured video is on the net, the game's over. And I'm ready to wager there's an awful lot of people out there who hate the *AAs enough to take the (small) trouble of doing exactly that, just to shaft them.

Re:Copy protection my butt

[Chirs]

It's actually pretty easy to remove macrovision. You can buy black boxes to do it pretty easily.

Re:Copy protection my butt

[pjrc]

If they make the crypto so good that difficult recapture techniques are needed... then doing so and offering the highest quality capture will become a challenge.

Much like the challenge today of posting the highest quality captures of currently running movies, whomever has the best rig and knows an insider to grab a copy of the disc shortly before release will go to extrordinary lengths. Like today, and as it's been in "warez" since the 80's Apple ][ and C64 games on BBSs, they'll get to promote their silly handle/name/slogan. Their group gets a few minutes of underground fame for having an elite, pristine copy early. Of course, in a matter of days, lots and lots of these second tier folks without the fancy gear get their few minutes of fame, being part of such an elite group... by impressing their friends with high quality copies of the new flick. Soon it's on p2p networks and mundane.

But there's always some new, shiney thing to pirate.... some new thing, that if obtained at the highest quality during that brief, fleeting period of newness, is cool. It's fun. If copied in their tiny window of time, it's elite. It's a powerful motivation to a class of very talented folks who, saddly, don't want to or have the opportunity to direct their energy to more worthy goals.

Once these discs are out, and before the crypto is really broken (took 3 years before anyone hacked css), these HD discs will provide that hacker motivation. Most likely, they'll be recaptured and turned into 4.5 gig mpeg4 avi files suitable for burning to a dvdrw.... with a few minutes of fame for the elite hackers with HD capable recapture and early access, followed by lesser but still very enjoyable minutes of fame for armies of trickle down until they hit the p2p networks.

The more things change, the more they stay the same (but substitute ftp sites, websites, usenet binaries groups, or even BBSs for "p2p networks").

Re:Copy protection my butt

[b1t r0t]

Another problem is that by the time it's in Blockbuster, it's way too late. Between cammers and insiders, a given movie gets warezed within days of the theatrical release.

Re:Copy protection my butt

[shimmin]

Except that pirated movie files, by and large, don't come from copied DVD's. They usually come from movie industry insiders and movie theater employees. Even if a DVD copy-protection system works, for the movie industry, it's like plugging the hole in a bucket whose bottom has rusted out.

Re:Copy protection my butt

[greed]

It's actually pretty easy to remove macrovision. You can buy black boxes to do it pretty easily.

Heck, my cheesy Dazzle Analog->FireWire->Analog converter yanks out Macrovision. So you get a decent DV stream from a Macrovisioned source. Or, if you leave it in "analog through" mode, it removes Macrovision from the analog signal. Good enough for converting VHS and LaserDisc to DVD with Kino.

Dedicated "signal stabilizers" are cheaper, and probably suck less than anything Dazzle has ever made.

Re:Copy protection my butt

[phoenix321]

What I can see, I can videotape. What I can hear, I can record.

If most else fails, I will film my own TV screen with my camcorder, the line from headphone-out plugged into it. Plain old cinema-piracy-style. And *then* put it on the internet or make a million copies and sell it cheap through illegal thrift stores. How do you prevent this? Mandatory watermark detection for all camcorders? What if I import them directly from China, Mexico, Russia or else? Arrest me for using illegal media equipment? Need to register typewriters and camcorders then like sometimes ago in Soviet Russia? ;)

Have an Orwellian society or movie studios bitching about unlicensed movie copies. Can't have both. You decide, today.

If *all* else fails, we can still vote from the rooftops, tomorrow.

Realistically, this can't work.

[rincebrain]

I don't care how secure the encryption is, as everyone has already said, all it takes is a "legal" DVD player outputting a high quality signal into a capture card, and you have a decrypted copy.

I doubt that the industry is foolish enough to force consumers to upgrade their televisions to support some form of signal encryption, therefore this must fail.

Re:Realistically, this can't work.

[Wesley Felter]

I don't care how secure the encryption is, as everyone has already said, all it takes is a "legal" DVD player outputting a high quality signal into a capture card, and you have a decrypted copy.

And where can you buy an analog HD component capture card?

I doubt that the industry is foolish enough to force consumers to upgrade their televisions to support some form of signal encryption

They did; it's called HDCP. If your HDTV doesn't support HDCP, you'll only get an analog signal.

Re:Realistically, this can't work.

[Hognoxious]

I doubt that the industry is foolish enough to force consumers to upgrade their televisions to support some form of signal encryption

They don't need to even try; consumers are probably foolish enough to do it voluntarily if it's bundled with the next big shiny new gotta-have feature(tm).

Same old, same old.

[sqlrob]

This has the same flaws as all of them.

The authorized user and the attacker are one and the same. You can't protect against that, not with cryptography.

Re:One step forward...

[Anonymous Coward]

...else the AACS will be the next DCMA.

I don't think you have any idea what you're talking about...

Such effort to prevent such an easy workaround...

[StevenMaurer]

Honestly - I work in the industry, and I'm still amazed at the lengths content providers will go to to try to prevent a single D-to-A, A-to-D conversion.

Apparently they just don't get that people - who seem willing to buy cheap videos recorded on consumer cameras in movie theaters - are going to be completely unable to see the difference in a re-recorded playback of what they see on T.V.

Folks - if you're too stupid to realize the network effect will swamp the casual copyright infringement, do something simple: don't release it. That's your only option.

What I want to know is

[Lurker McLurker]

Will this work on linux or will we have to rely on a HD-DVD Jon?

Especially considering

[melted]

that re-digitized HDTV stream will have better quality than direct rip from a DVD.

Re:Especially considering

[rokzy]

> that re-digitized HDTV stream will have better quality than direct rip from a DVD.

how?

on this website we obey the laws of thermodynamics!

Re:Especially considering

[drinkypoo]

What do laws of thermodynamics have to do with this? What the sibling comment to this one does not tell you is that full HD resolution is substantially higher than DVD resolution. DVDs are 720x480, while HDTV resolution is either 1920x1080i or 1920x720p... about twice the resolution, thus four times as many pixels. If you make an MPEG4 video from it you can indeed get dramatically better quality than a DVD. Of course, many (most?) people just make DVDs out of their captured HD content, because that makes it easiest to play it back. A DVD from a HD stream can look as good as a high-quality factory-pressed DVD.

This is a social issue

[grasshoppa]

Copy right violations and the like are a social problem, and are going to be solved with a social solution.

We can throw all the technology and litigation we want at the problem, but it won't be solved until we come up with a social solution.

Re:This is a social issue

[HarveyBirdman]

Copy right violations and the like are a social problem...

And therefore insolvable.

Simple

[paranode]

It's not necessary, but the movie industry has the illusion that if they make it harder to copy then somehow they will sell more. Remember, in their fantasy world each illegal copy is retail price lost.

A question for the crypto-experts

[P-Nuts]

So the proposal seems to be, content on DVD is encrypted with AES, using some random key. The key is stored on the DVD, but encrypted against another key, which is part of the player. How do you distribute this key inside players, without people being able to dig it out? Is it by putting it in a hardware-only form, like the chip on a smart-card? How easy is it to hide such a key in compiled software?

Stealing using recorders ???

[AtariAmarok]

"The Entertainment Industry assumes that all uses of recorders is for stealing copyrighted material. But that simply is not the case"

Correct. It is technically impossible to steal a thing using a recorder, unless you do something really odd like club a victim witha VCR during a mugging, or heave a reel-to-reel unit through a jewelry store window in order to break in and burglarize it.

Copying your butt

[AtariAmarok]

Is this device compatible with DRM?

Nice article

[Xcott Craver]

Glad to see a magazine article quoting a real security expert (Dan Wallach) rather than some random VP of marketing for a "content management" company. Spectrum doesn't even commit the common media sin of giving equal time to some crazy guy in the name of artificial fairness.

In any case, I am less worried about the crypto, which doesn't affect video quality. Fingerprinting of video and audio with watermarks can affect quality; in copy protection circles, you'll see iffy technologies proposed simply because they "can't hurt" to throw them in---but then some of them are detectable by golden eyes/ears. IMHO even that much quality loss is not worth whatever security a watermark offers.

Caj

Re:Such effort to prevent such an easy workaround.

[micromoog]

Indeed. This will just accomplish nothing to solve their problem, and will just create more problems similar to mine:

I can't play discs 3 and 4 (the appendices) of the Two Towers Extended Release on my standards-compliant Zenith DVD player, because of a botched copy-protection attempt by the manufacturer.

If this problem keeps getting worse, the number of movies I buy will continue its asymtotic approach of zero.

They must be on crack...

[Otto]

Seriously. I can't come up with another plausible reason for anybody to think this would work. Example:

The key to the spirit of compromise is an agreement that the AACS specification will allow consumers to move the data on an optical disc to the various devices they own, including video servers and portable video players, either directly or via a home network. In all the scenarios developed by the AACS alliance, that data would exist on the disc in encrypted form. It would stay encrypted when transferred to other devices and would be decrypted by those devices. The details of this portability have not been announced, but the technological underpinnings are expected to be included when the first version of the copy protection specification is released.

Now, understand that the encrypted content will be encrypted with a different key for each piece of content. This is just obvious and similar to how CSS works. The reason is so if you break one DVD, you don't break 'em all.

But this means that the key to decrypting the content must also be on the DVD itself. So that must be transferred to the portable device as well, in order for it to be playable.

So there's two ways this can work:

Method 1: Transfer the key along with the encrypted content in a plain form. In which case the attacker figures out where the key is, decrypts the content, creates an unencrypted version. Tada!

Method 2: The player key system whereby every company/player has a key and they are each used to encrypt a copy of the content key, which is placed on the disc. Thus this keyring must be transferred to the portable device and the portable device must itself have a player key to decrypt the content. I'm betting this is the method they're going for.

In which case the crack is simple: Compromise the player key. The player key must be embedded in the device somehow. In fact it'll have to be embedded in *every* device. All it takes is one hardware hacker to yank out a player key and voila, every disc up to that point can be decrypted.

So they invalidate the player key for future releases, breaking all existing hardware using that key. They could have done this with CSS, BTW, but they didn't for fairly obvious reasons.

In any case, this helps them not in the slightest. Because now you have a means by which to crack the rest of the player keys. Look, you get one player key. You have a disc with encrypted content for all player keys. You know the plaintext for what these are encrypting (the content key). Furthermore, every disc made that you can decrypt (probably a lot) gives you a new data set. How long do you think it'll take some bright boy to come up with a known plaintext attack on AES to retrieve these keys? It might be computationally intensive, but certainly it'll be less than a brute force attack.

And then what do they do when all keys are broken? They're straight fucked then.

The very idea itself is stupid. It's bound to fail in the same way CSS did. It'll just take a little more time, that's all.

There will be a lot of time to crack this

[Omegalomaniac]

Current plans seem to have HD-DVDs embedded with a traditional DVD layer to work on older players. We could still rip that DVD layer.

It's not like bandwidth is fast enough that there is huge demand for slinging around high definition 4 GB movies. Most discs are ripped and compressed to around 700 MB. It's going to be years before there's any demand to rip the new format.

Worry not....

[nother_nix_hacker]

....DVD Jon has come up with a crack already, just from the text of the article! :)

At what point does it become

[CodeWanker]

an attractive nuisance? Based on all the suggestions in the posts above, everyone is sick of the adversarial relationship with the motion picture industry and a lot of people have adopted a "bring it on!" mentality.

You don't go after the hardware and software, you go after the criminals. The *AAs are treating the population the way the government treats us via the war on drugs: irresponsible and guilty.

The hard costs of a DVD and all its sexy packaging? A dollar. The value of the IP (how badly people want to see/own it) on the disk? Varies wildly. What are the options the studios have? 1) price according to IP value, 2) sell disks only to video rental places, who rent them out until the cost is recovered and then sell them used, 3) keep trying the crap with copy protection, 4) go after the IP thieves. I wonder how often they'll have to choose before they try something other than 3?

Economics isn't the problem for the movie industry

[PCM2]

The movie business is going to hit the same wall as the audio business did, and the solution the audio business came up with (well, more accurately, were forced into) was to make the downloading of songs relatively cheap (under $1). As soon as it's not worth it to go through the hassle of copying the data, it is once again a viable product. At the moment, the movies are not viable products...

Back in the 1980s, the movie industry propped up the video market by charging a fortune for movies. Most were priced in the $90-150 range, well out of the market for the common consumer. Then video stores came along and started charging anywhere from $5 down to $2 a night to rent movies. The movie industry wasn't too happy at first, but then they realized they suddenly had a decent market who could afford their products, in the form of video stores. Eighteen zillion mom-n-pop video stores were popping up in every town in America. So instead of dropping the prices of all the tapes to encourage people to buy them, rather than rent them, the movie industry hung onto the high price point and that became "priced for rental." You weren't meant to buy it, unless you were rich -- video stores were. Only certain sure sellers were "priced for sale," which meant around $15-20.

It was only when DVDs came out that the industry's policy shifted to issuing new releases priced for sale. That's because there was a guy in the industry somewhere that convinced everybody that a durable media format (vs. shoddy VHS tapes) that contained a high-quality version of the movie was something a large number of people would be willing to own, rather than just rent. And he was right! People are buying DVDs in droves. DVD players were adopted by the mainstream public faster than any other electronic gadget in history, from what I've heard.

What I'm saying is, this theory that people download AVIs because DVDs cost too much just doesn't ring true. DVD sales have been phenomenal. If you think there's a DVD piracy problem in this country, think again -- check out the situation in Asia if you want to see a DVD piracy problem. I think people download AVIs because they're there. They can get the AVI before the actual movie comes out, and they can get the AVI for free for a movie that they probably wouldn't have bothered to buy, or even walk down to the video store to rent.

I mean, come on -- you can still rent DVDs. Are you honestly telling me that a price point of $3 for three nights (or whatever Blockbuster is doing right now) is more than most Americans are willing to pay to see some random shitty Hollywood movie? Of course it's not. But downloading AVIs, for many people, is just too easy.

This Too Shall Pass

[ausoleil]

The quote at the bottom of the article is telling:

"It is not a matter of if--it is a matter of when. As long as I have the technology in my living room to watch it for myself, I can modify the system to extract the video. They can make it hard, but they can't make it impossible."

How true. In other words, a lock only keeps an honest man honest, a thief will find a way to pick the lock and steal what you have.

Seemingly ever since there have been personal computers, there have been one form or another of copy protection. Usage such as backup copies (critical in the floppy days, nearly as much so with CDs and DVDs) have always been looked down upon by the content providers, and at the end of the day, all of the barricades that they have thrown at the user have eventually been thwarted and bypassed. Now comes HD-DVD and the same principle. I suppose some never learn from the past.

Working against the encryption is the simple fact that on the average, computers get more and more powerful (for a given price point), and that their encryption must remain a relative constant due to compatibility. That said, it is only a matter of time before the encryption is overwhelmed and utterly defeated. This will happen again, always has, and always will. One only has to look at the DirecTV versus the signal pirates to see that. Coupled with human nature, that is, to show and share a "dirty little secret" -- disaster for the encryption advocate. After all, are theyu going to disable dozens of models of players, and disable their own market in the process, not to mention alienating the hell out of their customers? No, no and no.

The key to copy protection is to make the content affordable enough to make the inconvenience of counter-enryption not worth doing. They (the collective they) never seem to get that, and they always seem dumbfounded that their elaborate measures are made to look foolish. Perhaps with realistic pricing, enhanced value they would find that most people find it easier to be honest, and not bother with cloning over-priced half-rate films and music. After all, that's their only realistic choice, but the one that they dread making the most.

Re:Such effort to prevent such an easy workaround.

[LihTox]

Honestly - I work in the industry, and I'm still amazed at the lengths content providers will go to to try to prevent a single D-to-A, A-to-D conversion.
Apparently they just don't get that people - who seem willing to buy cheap videos recorded on consumer cameras in movie theaters - are going to be completely unable to see the difference in a re-recorded playback of what they see on T.V.

If the movie/record companies are truly more worried about digital copying than about analog copying, they should make degraded versions of their movies/albums available for free or for a small fee. Dries up some of the bootleg market, but there's still an incentive for some to go out and buy the CDs/DVDs.

The powers that be are wasting their time.

[mmell]

How many ms do you suppose it'll take to read the content of the ROM chips in next-gen DVD players and extract the key(s)? Even if I don't have the hardware resources to read the ROM chips, I'll bet some cracker somewhere does -- I'll just wait for him to publish to the internet. Even if the key is rendered invalid, I'll still get access to all of the media made before that point (and just have to wait for the next crack to get more content).
Perhaps it's time for us to rethink the intent, meaning and form of intellectual property protection?

hoodwinked - everything to do with royalties

[Splork]

this scheme, as with decss, has nothing to do with copy protection. that is merely its disguise. it has everything to do with mandatory royalties to the consortium from all dvd player manufacturers and dvd mass producers. its all related to control over who makes and sells media players and what they are capable of doing or not doing out of the box.

mpeg4

[kardar]

The HD-DVD and the Blu-Ray players both support the mpeg4 formats. While the disks you buy from the store might be all messed up, either play or not play, there isn't really anything stopping anyone from taking some mpeg4 content and placing that on a Blu-Ray or HD-DVD blank; those will probably play every time, more or less. It would not be surprising to see iTunes-like services springing up around the mpeg4 format.

What's going to happen is simple: the HD-DVD thing isn't going to take off; not if you have to keep upgrading keys all the time. Joe and Jane Average are probably going to stick with the regular DVD from Netflix, Blockbuster, or whomever, knowing that it will work every time.

If the new formats can be gotten to "work every time", perhaps by having the keys downloaded from the internet or something like that, then they might do better. Anytime you make something too complicated, though, it's bound to fail. Look at 3D movies with those uncomfortable cardboard 3D glasses. Where have they gone? Look at DVD-Audio or the SACD? Going nowhere fast. Lossless compression formats from iTunes or other services? We're not really there yet - if people are willing to settle for mp3 or aac quality sound, why would they want to spend extra money on a DVD-audio quality sound?

The movie industry risks entering a situation not unlike the music industry finds itself in today. Many of the same symptoms are there; the same attempt to control is there; the same low-quality, high-budget, intellectually lacking content is being pumped out. A new format that is harder and more expensive to use just isn't going to cut it. It would not be surprising to see mpeg4 take the place of mp3 files, with people cramming movie after mpeg4 movie onto a DVD5 or perhaps a DVD9 that they either downloaded from a legitimate service, or if no such legitimate services happen to spring up in the near future, a p2p network.

The popularity of iTunes and other legitimate music download services goes to show that consumers don't care so much about the absolute highest sound quality, but that they care more about convenience, selection, ease of use, accessibility, and things like that. These new formats are probably more or less doomed to not do as well as they could.

These new disks, though, the Blu-Ray especially, these are going to be GREAT for backing up systems, documents, and also for businesses to do backups and things like that. The technology is awesome; what Hollywood is trying to do with it is the part that isn't going to work very well.

Try before you buy

[Spy der Mann]

There's something we've forgot.

You don't sit in front of your computer monitor along with your wife and kids to watch a divx movie on your media player. Generally divx users are 20-30 yo's, or even kids who downloaded the latest anime episode.

So who gets the benefit of a downloaded movie? ONE person per family. If the movie wasn't good, the guy wouldn't watch it along with his g/f, wife, kids/friends/etc.

So what does this mean: "Try before you buy". Simple. Here I'd be questioned: "Oh come on, what person watches a movie TWICE"? Ask the starwars fans who watched "Star wars: A new hope" the day it came out in theaters. They watched it once. Twice. Even 20 times.

So, if a movie is REALLY WORTH it, I'm sure people would actually purchase the DVD or go to the theaters, even if they already watched the downloaded thing. Why? Because the movie DESERVES IT.

The real enemy here is not piracy... but freaking poor quality overhyped movies with pre-paid (as opposed to impartial) reviews.

The movie producers are committing FRAUD by telling us the movies ARE WORTH seeing, when they're not. Same with videogames. I remember playing FFX-2... and I could compare my feelings with a girl who didn't achieve climax on her most expected date. "What? This is it? WTF?" Same with Robotech: Invasion (79 bucks thrown to the trash, man!) and Spider Man for the PS2.

So, MPAA and associates: Want more profit? Make better products, and stop complaining.

Addendum: Maybe the MPAA is actually whining because they CAN'T FOOL the public with hype (Pearl Harbor, anyone?), and people won't purchase bad movies DVD's or go to the theaters if the "evil pirates" already review the movie and say it SUCKS. And _HERE_ is the profit loss. In any case, this reinforces my opinion:

Make better products. Period.

Open Source players

[kieronb]

The big question for the Linux/FOSS community isn't how hard is it to crack: it's can we be included without being forced to crack it.

I'm sure I'm not alone in not wanting to make pirate copies of DVDs, but just wanting to be able to watch my discs on the equipment of choice, including open source players.

This boild down to: i) will the algorithm be well known (ie rely on secrecy of keys not the algorithm) and ii) how do you get allocated a key

CSS sucked because it used weak keys and tried to keep the algorithm secret. The first rule of cryptography is to assume the algorithm is known, and thanks to DVD Jon we got it reverse engineered. And it sucked for the FOSS crowd because you couldn't make a player without paying a huge sum of money and signing all sorts of agreements.

If the new system removes these barriers to entry, then it at least it won't be as evil as the original CSS. It'll still be useless, but not actually evil.

Re:Hardware crypto

[slide-rule]

Of course, it's totally irrelevant how tricksey the DVD player itself is w.r.t. crypto, so long as the unit has to send a decoded signal that any cheap Wal-mart-purchased TV can view. For practical purposes, this Achille's Heel just can't be solved w/o getting everyone (consumers) to throw all their {A/V gear, players, televisions, PC's} out and start over.

Bulletproof Method

[hwstar]

Use a non-standard optical encoding method.

Don't allow PC's to play disks.

Players refuse to play unencrypted content.

Use a smartcard to do all authorization.

Require an internet connection or phone line
to authorize playback each time a disk is loaded.

Don't store any keys on the disk.

Build the display into the player.

Pot the inside of the player with a potting compound which when compromized, causes the player to burst into flames.

The keys appear to be symmetric

[thpr]

They've done a decent level of design on this one.

The key appears to be symmetric; it's just blazingly complicated to calculate the actual device key ... and allows for multiple derivative keys from a master key stored in the hardware of the device. Masks included in the decode area on the disk provide the path to get the unique key to decode the disk... which (from a 30 minute review of the technical document) could theoretically(?) be used to provide different derivative keys per disc, so even if you capture one of those, it may only help with that print run of that disc. The key is getting back to a master key and its seed; the problem (to the crackers, at least) is that once that is done, the licensing association can disable that key without killing any consumer devices.

The amount of computation back to the original keys makes any attack against the system imprudent at best, and the use of derivative keys and multiple master keys per device means that even if one were cracked, the others in the device would continue to allow consumer devices to function... which avoids consumer backlash.

From my (semi-educated) analysis, it looks "good" (for the *AA) so far.

Dialogue.

[Grendel Drago]

So, what would you recommend for good dialogue? I really enjoyed the rhythm and style that everyone in Firefly spoke with. The dialogue wasn't just there to advance the plot.

Or Scrubs, and the little rants that Dr. Cox goes on. (A doctor I know assures me that the portrayal of hospital life in Scrubs is far, far more accurate than that in ER. Go figure.)

Are there any other shows I should fetch for their scintillating dialogue? Please don't tell me "CSI". I've been refusing to watch "CSI" ever since the only episode I ever saw centered on "look, perverts! perverts murder people!". As a pervert, I felt insulted.

--grendel drago

This is *playback* protection, not copy protection

[David McBride]

This was never about copy protection.

No form of encryption will not make it harder to copy the original disk. Constructing a bit for bit copy of a digital stream in no way requires you to be able to understand the data being copied.

Rather, this is a playback protection system.

It's to stop you from watching the media when the distributors don't want you to be able to. Such as, for example, should you try to play a movie released in the US which is only just being shown in movie theatres in Western Europe. Or Asia. Or anywhere other than Region 1.

Encryption of the media is only there to force DVD player manufacturers to obtain a key -- which will only be provided if they also sign a contract to adhere to certain terms and conditions that, in essence, states that they're not allowed to undermine the distributors' business model.