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DVD-Jon Breaks iTunes Encryption For Linux Users

McGruff writes "The Register has a story regarding DVD-Jon's new hobby, iTunes DRM. According to the story DRMed iTunes AAC files can now be played under Linux via VidioLAN Client thanks to some handywork by Jon. '"When you run the VideoLAN Client under Windows it will write the user key to a file. The user key is system independent and can thus be used by the GNU/Linux version of VLC," he explains.' Personally, this just means I will buy even more iTunes." (We mentioned in November Johansen's efforts to negate the iTunes restrictions on Windows.)

37 of 584 comments (clear)

  1. Key exchange ? by Jesrad · · Score: 5, Interesting

    How long before people start exchanging their keys ? Now that the key can be had and used under virtually any platform, in an easily copied or transmitted file format, the copy-protection is effectively cracked.

    --
    Maybe we deserve this world ?
    1. Re:Key exchange ? by salimma · · Score: 5, Insightful
      RTFA - You need to exchange the key *and* the file itself, as the key is tailored to each computer. iTMS reps could then easily block computers with said Windows Product IDs.

      This hack is, OTOH, useful for 'fair use' - for people who dual-boot Windows and Linux. As well as dedicated music pirates who would re-share the unlocked files as plain AAC.

      --
      Michel
      Fedora Project Contribut
    2. Re:Key exchange ? by B'Trey · · Score: 5, Insightful

      Even if the price is the exact same, being able to purchase by tune is still a major win for the consumer. Even my favorite artists have tunes that I don't particularly care for. They're not necessarily "just filler," or bad songs but they don't appeal to me. There are other artists that I'm not really a fan of but I like one or two songs. The bottom line is that this puts choice in the hands of the consumer, and consumer choice is a good thing.

      --

      "The legitimate powers of government extend only to such acts as are injurious to others." Thomas Jefferson.

  2. How long... by 3Suns · · Score: 4, Interesting

    Awesome, I was waiting for this. Definitely a reason to consider iTunes now.

    How long until someone writes a command-line AAC2mp3 converter?

    --

    -3Suns

    ~~~~
    The Revolution will be Slashdotted
    1. Re:How long... by moosesocks · · Score: 5, Informative

      It could be done with AppleScript under OS X. Simply tell itunes to play a given song, tell any old sound recording app to dump the computer's sound output to a WAV, convert to MP3 using LAME, and then grab the song's info via. AppleScript and put it into an ID3

      The downside here is that you're losing quality encoding to MP3 (remember that AAC is also lossy). Unfortunately, there is no way to preserve full-quality without retaining the original file format.

      Either way, I frown upon this sort of piracy. $.99 is pretty darn cheap (Note here that I have no objection to using this to play your OWN files under linux if it is the operating system of your choice. Just keep it to yourself)

      --
      -- If you try to fail and succeed, which have you done? - Uli's moose
    2. Re:How long... by Nasarius · · Score: 4, Interesting

      Exactly. That's why if you want me to buy music online, you had better be distributing it in a lossless format (FLAC, SHN, APE, whatever...I don't care as long as I can get the original WAV).

      --
      LOAD "SIG",8,1
    3. Re:How long... by Zork+the+Almighty · · Score: 4, Informative

      Uh, Xvid has gotten a lot better than you give it credit for. See Doom9's latest codec comparison.

      --

      In Soviet America the banks rob you!
    4. Re:How long... by iammaxus · · Score: 5, Insightful

      Why do people insist on things like this... I would really like to find the person who could honestly tell me that they enjoy a 192+ kbps encoded (mp3pro, aac, wma) any less than the cd. Can anyone really hear any loss during regular use? People just like to _know_ that they are listening to a completely, totally, 100% original even though they would probably never know. And like the others who responded to this comment, what's the point when these files are generally being encoded directly from masters which yields _better_ results than what you want (a 100% copy of the cd)

    5. Re:How long... by Lost+Race · · Score: 4, Insightful
      MP3 frames are something like 25 ms in duration. That's 0.025 seconds for a complete frame. An extra partial frame to pad out the end of a track would be less. That is nowhere near 1/2 second -- if you have 1/2 second gaps between tracks it's your encoder (or maybe your player, or possibly your CD ripper) inserting the extra blank space.

      You might hear a single 100% silent frame between songs as a "click" (maybe, if you listen carefully) but in reality there would never be a 100% silent frame inserted, and most decoders are pretty good at covering up inter-frame glitches.

  3. This is a wonderful breakthrough by lynxuser · · Score: 5, Interesting

    I am quite excited about this. VLC has always been my media player of choice, now the ability to play AAC DRM files in it just ups its ante.

    While booting to Windows is a slight disappointment, I am sure DVD-Jon will remove that step ASAP.

    --
    I read Slashdot in Lynx, I am a real geek.
  4. What does this guy do for a living? by cacheMan · · Score: 5, Interesting

    What do any of these people do with free time to break encryption schemes, contribute to oss, and build robotic girlfriends? I'm serious, how do you earn a living and still have time to do things like this?

    1. Re:What does this guy do for a living? by Frisky070802 · · Score: 5, Funny

      I think he's a professional defendant, or wants to be.

      --
      Mencken had it right. So glad that's old news.
    2. Re:What does this guy do for a living? by asavage · · Score: 5, Informative

      He was 15 when he broke the DVD encryption and now he is still only around 19. He doesn't need to work for a living yet.

    3. Re:What does this guy do for a living? by glitch23 · · Score: 5, Funny

      Who ever said they earned a living?

      --
      this nation, under God, shall have a new birth of freedom. -- Lincoln, Gettysburg Address
  5. iTunes on Linux by ZWarrior · · Score: 5, Interesting

    Somehow I think that this is an example of the way software restrictions will continue.

    Programmers will code the security so that the app only works one way, and some user will break it s it works elsewhere as well.

    We need to have more thought put into coding so that apps will work more platforms, and also be aware that it is envitable (sp?) that somebody will crack it.

    I broke a lot of digital clocks as a kid because I wanted to know what made them tick! I still got new ones, and broke them as well.

    --
    Here I come to save the da... *thud*
    I gotta get me a shorter cape.
  6. Re:Windows Only??? by Anonymous Coward · · Score: 5, Insightful

    Does anybody else see something wrong with Apple having a program that only works on Windows and Macs? You would think they would be a little bit more understanding of those of us running "alternative" OSes.

    Yeah, it's not like Apple has a vested interest in one operating system over another!

    Oh wait...

    Guys, Apple is no more altruistic than Microsoft. Apple is only cool because they are the underdog. Don't be expecting Apple to be something they aren't. That's where Linux and Open Source comes in.

  7. But by ITR81 · · Score: 5, Insightful
    But I think all Apple needs to do is update QT and update it's DRM.

    Seems like this crack can be patched.

    I doubt Apple will call DVDJohn but I bet the RIAA will.

    1. Re:But by exhilaration · · Score: 5, Insightful
      I doubt Apple will call DVDJohn but I bet the RIAA will.

      It's Jon, and he'll tell them that their American threats don't mean jack in Norway.

      By the way, I sure hope that he has no plans to visit the U.S..

    2. Re:But by jared_hanson · · Score: 4, Interesting

      According to my understanding, his first "crack" would be possible to patch as it exploited the functionality of QuickTime that made an unencrypted AAC stream (or PCM stream?) out of the protected one. It then dumped this to a file absent of DRM.

      His new crack actually writes the decryption key out to a file. This key is written out using Windows and is apparently derived from hardware serial numbers, such as that on the hard drive. This key can then apparently be used to decrypt the protected files on any OS. I haven't given this a shot yet, but it should be interesting to find out.

      Personally, I don't care all that much, as I use iTunes on OS X and an iPod to listen to most of my music. However, I would like to serve up my protected AAC to my squeezebox, and this just might allow for on the fly transcoding to a PCM stream from SlimServer.

      It would be pretty tough for Apple to go and make another DRM scheme that avoided this without breaking backwards compatibility.

      --
      -- Fighting mediocrity one bad post at a time.
  8. DVD-Jon is a terrorist! by Anonymous Coward · · Score: 5, Funny

    When will the this commie bastard be stopped from stealing money from corporations?????

  9. Re:Does iTunes music store work under Linux anyway by exhilaration · · Score: 4, Informative

    No, you need the iTunes client to play any files you buy from the iTunes store. And No, it doesn't (yet) work under Wine or CrossoverOffice.

  10. I just might ruffle some feathere here.... by mental_telepathy · · Score: 4, Insightful
    You would think they would be a little bit more understanding of those of us running "alternative" OSes.

    That would be the way for apple to go if they were in it to make everyone feel good. But actually, they are in it to make money. And as you may have noticed, a lot of linux users don't like to pay for stuff. This is smart for Linux users, not so good for people trying to make money off of Linux users.

    And of course, it could never be enough. port itunes to linux? Where is the Ogg Vorbis support? Got Ogg? Why doesn't it work with *insert random peice of sourceforge developed software here*

    I know, nobody wants to hear that they are the prima donnas of the IT world. But I've got Karma to burn.

    1. Re:I just might ruffle some feathere here.... by macjohn · · Score: 5, Insightful

      You forget where the money is: it's in iPods, not in the music. They don't make any money on the music. But every platform they can hook to an iPod is a win. So doing a Linux port certainly doesn't hurt them and may help.

      --
      --Hi. I'm in Portland and it's raining. This appears to be a permanent condition.
  11. Wait by pHatidic · · Score: 5, Funny

    So can we change his name to iTunes-Jon. Or better yet how about iDVD-Jon. Kinda catchy, actually.

  12. Sounds cumbersome for swapping by Bakafish · · Score: 5, Interesting

    Not that I would advocate such use. But this requires the key to be distributed with each file. Keep in mind that said key is *known* by apple, and directly tied to your account, it isn't something I would recommend sending out into the wild. On the other hand, using it on your own equipment to get around that creepy three machine registration limit seems like a good thing. If anything ever happened to Apple and your registered machine bit the dust, being able to back up a valid copy of your key seems like a good thing.

    The thing is that AFAIK VLC isn't set up to manage multiple key+file pairs. So it is useful for *your* library, but not various files downloaded off the net. For that reason, I doubt they will go after him.

    My question is, how does the iPod decrypt the file without a key? Or is it simply using the parent boxes key? It seems to me that if that's the case it should be trivial to recover the key from an iPod directly, no PC required (Just a Mac :-)

  13. This is dangerous ground we tread on by grioghar · · Score: 5, Insightful

    On one side of the coin, this is definately great news for everyone not running Windows or OS X who still want to listen to their DRM'd AAC files. Now, there is some portability to these files, and the ability to cue them up in VLC.

    On the flipside, when some music industry execs look at this and wonder why they can't control their content, there are a number fingers going to be point at the OSS community because of it.

    Where do we draw the line at control? The **AA industries wants to control their content, and we (I use "we" very loosely) want to have control over that which we've purchased. But who truly owns the bits? A series of 1s and 0s? Who's allowed to make the rules?

    I know who I WANT to make the rules, me, of course. But I also know who legally gets to make the rules at this point. Them. I don't want the music industry to get pissed off and take my iTunes away. I've found a legal, beneficial means to aquire my music. I want MORE options, not less because of wary industry execs who don't want to have their content cracked.

    And let's not even bring the DMCA into the picture here...

    --
    Can you ping me now? Gooood! | Manhappenin.Net - Things to do
  14. Re:Leave it alone by exhilaration · · Score: 4, Insightful

    He's trying to play media that he legally purchased on Linux. This is exactly the argument that he used in his DeCSS defense. Until Norway passes a law making that illegal, he's perfectly safe.

  15. Slightly Off Topic... by Luke+the+Obscure · · Score: 5, Funny

    I can't wait until all Slashdot comments are nothing but long strings of esoteric acronyms.

  16. Re:Is this guy an idiot? by GoofyBoy · · Score: 5, Insightful

    >Kid, seriously, grow up.

    What is wrong with him doing this and staying like this forever?

    I mean, he should stop doing something just because "other people who know better" say that he should stop?

    Should he stop becuase he could get into civil legal problems? That doesn't stop lots of "adults".

    Should he stop because its "wrong"? Maybe some one could tell me where this is ethically wrong becuase I don't see it.

    I say that he should keep doing what he likes to do and accept the consequences until he feels he shoudn't anymore and not what other people say.

    Because in the end its his life.

    --
    The surprise isn't how often we make bad choices; the surprise is how seldom they defeat us.
  17. Re:Is this guy an idiot? by JoeShmoe · · Score: 5, Insightful

    Troll or clueless, I can't tell because as AC there's no post history.

    Consumers, at least in Norway, do have more rights. They have the right to use DeCSS to decrypt DVD video to video on the player of their choice. They also, presumably, have the right to publish and obtain the DeCSS program.

    Now, back in the land of the free, we have no such rights...why? Because we pussed out. We decided not to pursue our DeCSS case and let stand a lower court ruling that banned it. Oh yeah, this was much better than what Jon did, namely stand up for himself in court.

    I'm not so naive to believe that Jon was selfless in his act (he was part of or closely associated with warez groups who were keen on cracking DVD encryption to allow for perfect all-digital rips rather than having to use analog loopback to capture card). But even if DeCSS has a seedy or sordid history no one wants to talk about, the point stands that DeCSS does have legitamate uses and that is where Jon's defense was founded.

    When you have precedent set, you don't hide it in your desk and call it a day. You use that precedent to try and set new precedent that is even broader in scope. Jon has stood up to the might of Norway's MPAA/Attorney General equivalents, who now have major egg on their face. How likely do you think they will be to pursue another half-baked case against Jon? Jon is probably bulletproof against anything but real criminal behavior. As soon as the words "fair use" are uttered, I can't imagine there would be a government attorney crazy enough to get struck by lightning twice.

    Releasing it anonymously would have only started a witchhunt that could have harmed a lot of other people, people who shouldn't have to be lightning rods for this same kind of treatment. But putting his name on it, yes, he is risked another trial but as I said, it is rather unlikely.

    In this world full of people who puss out and settle for lesser charges (cough)Mitnick(cough) I think it's incredible that someone has the guts to put himself at risk to stand up for something. I only wish someone were that brave here in US courts.

    -JoeShmoe
    .

    --
    -- I wonder which will go down in history as the bigger failure: the War on Drugs or the War on Filesharing
  18. Re:Is this guy an idiot? by zulux · · Score: 5, Insightful

    Is this guy an idiot?

    Jon is a noble-hearted man who is standing up to tremedous odds and tremendous risk to fight for somthing that is good.

    'round here, we call people like that heros

    --

    Moneyed corporations, non-working 'poor' and criminal prisoners are turning productive citizens into tax-slaves.

  19. Re:Is this guy an idiot? by GlassHeart · · Score: 5, Insightful
    Millions of people jaywalk, and millions more drive their cars faster than the speed limit. What has that done to silly (in some places) jaywalking laws or absurd (in some places) speed limits? On most US roads, it's a well known rule of thumb that police would generally not bother drivers who speed by under 10 miles per hour over the limit.

    On the other hand, a frail man deliberately picked up a handful of salt, which was at the time a monopoly product of the British Empire. He was arrested for it, but this and other actions that fly in the face of "common sense" eventually freed India from British colonization.

    How about that woman who was arrested for sitting in the front of the bus, when everybody knows that black people need to sit in the back?

    I'm not saying DVD-Jon is anybody resembling Gandhi or Parks, or that his cause is nearly as important. What I'm saying is that many changes come from a small number of people noisily breaking unjust laws, rather than a thousand people quietly breaking it.

  20. Re:Windows Only??? by EvilSporkMan · · Score: 4, Informative
    QuickTime only runs on Mac and Windows.
    scott@allyourbase scott $ emerge -s quicktime

    *** You are not in the portage group. You may experience cache problems
    *** due to permissions preventing the creation of the on-disk cache.
    *** Please add this user to the portage group if you wish to use portage.

    Searching...
    [ Results for search key : quicktime ]
    [ Applications found : 3 ]

    * media-libs/libquicktime
    Latest version available: 0.9.2_pre1
    Latest version installed: 0.9.2_pre1
    Size of downloaded files: 644 kB
    Homepage: http://libquicktime.sourceforge.net/
    Description: A library based on quicktime4linux with extensions

    * media-libs/openquicktime
    Latest version available: 1.0-r1
    Latest version installed: 1.0-r1
    Size of downloaded files: 312 kB
    Homepage: http://openquicktime.sourceforge.net/
    Description: OpenQuicktime library for linux

    * media-libs/quicktime4linux
    Latest version available: 1.5.5-r1
    Latest version installed: [ Not Installed ]
    Size of downloaded files: 2,060 kB
    Homepage: http://heroinewarrior.com/quicktime.php3
    Description: quicktime library for linux
    What?
    --
    -insert a witty something-
  21. This is the perfect time. by stuartkahler · · Score: 4, Interesting

    I'd bet he started working on the iTMS project a long while ago. He's just been acquitted twice for doing the same thing with DVD encryption. Now that he has rock solid precedent, he can practically walk into court without a lawyer if the recording industry sues him. He's got a great big whoop-ass stick, and it's time to use it.

    In Norway, that is... Americans are still screwed.

  22. Wasn't me by The+Tyro · · Score: 5, Funny

    making it more accessible to the tyro

    I had nothing to do with it... I wasn't there... you can't prove anything.

    --
    Even if a man chops off your hand with a sword, you still have two nice, sharp bones to stick in his eyes.
  23. Re:Leave it alone by thparker · · Score: 5, Insightful
    He's trying to play media that he legally purchased on Linux.

    Maybe I'm behind the times. I thought iTunes was still a U.S.-only service?

    So how is Jon trying to play media on Linux that he's legally purchased when it can't be purchased in Norway? I'm just wondering.

  24. Relevant Information by Otto · · Score: 5, Informative

    After examining the code, here's basically how the iTunes encryption works:

    Every user account for iTunes gets a "user key". This gets sent to the computer at the the time of "Authorization" and gets written to a file on the hard drive. But it's not written out plainly, oh no. Instead, it creates a "system key" using several bits of data from Windows and the hardware and such. This system key is what's stored in the file.

    To playback a song, the system key is derived from the machine and used to decrypt the file on the drive. This gives the list of user keys that machine is authorized to play, and these will decrypt songs using the same account (yes, each song is encrypted at the time of download, with the user key for that account).

    This crack essentially works out how the system key is derived. Using that, it gets the user key, writes it off to a file, and can then decrypt any of that users songs.

    Note that when you transfer a song from iTunes to the iPod, it does the same basic thing. Decrypts the file using the system key and reencrypts it using iPod specific information, then sticks it on the iPod. The iPod then does the same process as iTunes to play the file, more or less, it's just using a different system key.

    This crack could be patched by changing the method to derive the system key from the machine, but not once the user key has been derived and written to a file somewhere. Once you have the user key, that can be used to decrypt the songs, and you're essentially done. Since you have the song files, and the key to decrypt them, no patch in the world could possibly fix it. They could fix it for newly purchased songs, but to do that they'd have to change every users key and reauthorize them. And that potentially breaks the authorization for songs that have already been purchased. They could start a new key without removing the old ones, in order to maintain backward compatibility and not piss off everyone who has used iTMS up until now, and then release new songs using only the new encryption, but it's essentially a dead end. The whole concept behind iTunes encryption is that once a machine is authorized, it can play songs without any outside intervention. Meaning that it has everything it needs to decrypt the songs right there on that machine. Meaning that as long as this is true, it can be cracked again.

    I knew it was only a matter of time. I give it another 2 weeks before someone takes the code out of the drms.c, drms.h, and drmtables.h files and produces an M4P->M4A converter. Everything really needed to do it is in there. You read in the file, call this code to get the system key, call the code to get the user key, call the code to decrypt the DRMS section, then rewrite the file with a normal AAC data section instead. Not too difficult, although interpreting Jon's code is a PITA to say the least. The guy writes C code that reads more like ASM. Frankly, looking at the code, I think he simply found the relevant part of iTunes/Quicktime with a debugger and converted the relevant machine language straight into C with no major adjustments.

    --
    - Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.