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After DeCSS, DVD Jon Releases DeDRMS 610

An anonymous reader writes "Jon Lech Johansen, who reverse engineered FairPlay back in January, and wrote the decryption code that was later used by an anonymous developer to create the playfair utility, has released a similar utility: DeDRMS. It's only 230 lines. T-shirts anyone?"
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After DeCSS, DVD Jon Releases DeDRMS

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  • by brunes69 ( 86786 ) <> on Sunday April 25, 2004 @05:02PM (#8967288) Homepage
    Not that I have anything against C#, I actually find it quite nice, just stuck me as odd that someone would write a cracking toolin it. These things are traditionally written in C ( for speed ).... like DeCSS was.

  • DeDRMS (Score:5, Interesting)

    by gnu-generation-one ( 717590 ) on Sunday April 25, 2004 @05:03PM (#8967293) Homepage
    "In practice, the goal of maximizing publication regardless of the cost to freedom is supported by widespread rhetoric which asserts that public copying is illegitimate, unfair, and intrinsically wrong. For instance, the publishers call people who copy "pirates," a smear term designed to equate sharing information with your neighbor with attacking a ship. (This smear term was formerly used by authors to describe publishers who found lawful ways to publish unauthorized editions; its modern use by the publishers is almost the reverse.) This rhetoric directly rejects the Constitutional basis for copyright, but presents itself as representing the unquestioned tradition of the American legal system.

    The "pirate" rhetoric is typically accepted because it blankets the media so that few people realize that it is radical. It is effective because if copying by the public is fundamentally illegitimate, we can never object to the publishers' demand that we surrender our freedom to do so. In other words, when the public is challenged to show why publishers should not receive some additional power, the most important reason of all -- "We want to copy" -- is disqualified in advance.

    This leaves no way to argue against increasing copyright power except using side issues. Hence opposition to stronger copyright powers today almost exclusively cites side issues, and never dares cite the freedom to distribute copies as a legitimate public value."

    Misinterpreting Copyright []
  • I am sure this will trigger another round of lawsuits, hopefully with the net effect of more education of the public and legal community as to the nature of source code as speech (that is, a method of communication).

    This code shows with more simplicity than ever before how the FairPlay DRM scheme works. This can be used by programmers to add support for applications (i.e., GStreamer) to play encrypted files with a key produced from an iTunes username/password. It can be used by researchers to see any weaknesses in FairPlay and develop better methods. Unfortunately it can also be used by those who want to destroy the iTunes Music Service.

    Interestingly, I believe the ideas could also be used to create files encrypted with a particular iTunes login, though perhaps I'm misunderstanding the scheme.

  • Re:Written in C# (Score:2, Interesting)

    by dAzED1 ( 33635 ) on Sunday April 25, 2004 @05:09PM (#8967346) Journal
    I could be wrong, but I think he was being sarcastic. Like, while p2p services have illegal things happen on them, people kill the p2p. Gosh, I guess I could be wrong...doubt it though.
  • DeDRMS art... (Score:3, Interesting)

    by Saeger ( 456549 ) <farrellj AT gmail DOT com> on Sunday April 25, 2004 @05:10PM (#8967349) Homepage
    Looks like DeDRMS will be next up for free speech protection in the tradition of the DeCSS Gallery []. I just love it when DRM control freaks get their global domination panties in a wad.

    DeDRMS? I wrote a song about it. Want to hear it? Hear it goes... *da dum da dum*... slash asterisk bla bla asterisk slash... *da dum da dum*... Using System; *bah bum bah bum*...


  • Re:Written in C# (Score:5, Interesting)

    by mrpuffypants ( 444598 ) * <mrpuffypants AT gmail DOT com> on Sunday April 25, 2004 @05:10PM (#8967355)
    I actually like the irony of a Microsoft pushed technology being used to kill an Apple-pushed technology THEN getting GPL'd!
  • by Anonymous Coward on Sunday April 25, 2004 @05:13PM (#8967384)
    C# is a pretty clean language, all in all. One of those things that MS got it right by successive approximation.
  • by Sarth ( 765570 ) on Sunday April 25, 2004 @05:17PM (#8967426)
    DVD Jon, of obvious fame, is hailed as a hero for letting your average Joe (or Jon), go out to their local store, and buy a DVD and play it on their linux boxen, right?

    I can sorta understand that, as far as I know, DVDs don't state at the time of purchase that you have to have X or Y, just that you have to have the disc. Fine.

    So, when you buy something from the iTMS, it STATES that you have to have X or Y. It clearly states the restrictions that you agree to. This is not a hard concept, so why is it felt that a technological solution is required to 'fix' it?

    Something that just struck me... DVD Jon isn't in the Americas, but iTMS isn't selling to those outside (maybe Canada, I'd have to check). So ... what part of this equation am I missing?

  • by sailor420 ( 515914 ) on Sunday April 25, 2004 @05:41PM (#8967589) Homepage []

    A temporary mirror to the code. It wont be up more than a week, so dont bookmark it.
  • Get it now (Score:5, Interesting)

    by Nom du Keyboard ( 633989 ) on Sunday April 25, 2004 @05:45PM (#8967619)
    Remember W.A.S.T.E.
    Remember PlayFair
    Remember the bitTorrent sites

    If you want it, get it now.

    Interesting how this news comes out on a Sunday, when the lawyers should all be out at play.

  • Re:ok... (Score:3, Interesting)

    by FrYGuY101 ( 770432 ) on Sunday April 25, 2004 @06:02PM (#8967746) Journal
    Mono changed the licence from LGPL to MIT...

    From here []:

    The class library is being licensed under the terms of the MIT license. This is the same license used by the X11 window system.
  • by Hatta ( 162192 ) on Sunday April 25, 2004 @06:17PM (#8967875) Journal
    I see a blaring difference between a DVD, which does not say 'Thou shalt not', and the iTMS, which does. That, to me, is the key difference. Informed consumers, implied (or explicit) consent to the purchasing guidelines thusly set forth. ymmv, obviously.

    So you do everything corporations tell you to do? You've never stood on the top rung of a ladder? Or taken a double dose of ibuprofen? Never used a beach ball as a flotation device? Once you buy it, it's yours and no one can justly tell you what to do with it. Not that the justice system is ever just, mind you.

    My main fear, is that the Big Five will use this, to either show that 'digital distrubution of music is an unsound business model', or something along those lines. BEST case situation now, we come out of this with a much heavier DRM than we have now. End result, only those willing to bend the rules come out ahead -- just like it is now. Thanks, Jon. Much

    Rules are for suckers. If something is morally wrong, good people won't do it anyway. Rules aren't going to stop the dirty ones. So the only reason to have rules is to stop moral people from doing something that's not morally wrong.

    Must the citizen ever for a moment, or in the least degree, resign his conscience to the legislator? Why has every man a conscience, then? I think that we should be men first, and subjects afterward. It is not desirable to cultivate a respect for the law, so much as for the right. The only obligation which I have a right to assume is to do at any time what I think right. It is truly enough said that a corporation has no conscience; but a corporation of conscientious men is a corporation with a conscience. Law never made men a whit more just; and, by means of their respect for it, even the well-disposed are daily made the agents of injustice.

    Henry David Thoreau, Civil Disobedience (1849)
  • by acamas ( 443784 ) on Sunday April 25, 2004 @06:27PM (#8967930)
    Everybody here seems to be glad about this hack. I'm not...

    Please think about it:
    1) Apple's DRM Fairplay is rather fair - at least compared to other DRMs. Every "normal" user that simply wants to listen to the music, that he or she bought legally, can do it. You can even burn it on CD and listen to it in your car. The only thing one can criticize it that the only mobile digital music player you can use is the iPod.
    2) The music industry still doesn't like digital music. Few days ago I read about the music industry demanding higher charges than 99cents, which in my opinion are quite fair as well.

    It was probably not very easy for Apple to convice the music industry of Fairplay being safe enough (think of all their competitors' DRMs). So what will happen now?

    a) Apple will be forced to shut down their Music Store
    b) Apple will have to update all their songs, the iPod-Software and iTunes. I guess, the new DRM will be more strict....

    So what do we get from PlayFair and DeDRMS? A quite reasonable product will be gone.

    And you can be sure, this development won't help the music store expanding to the rest of the world, either.
  • by solid ( 15355 ) on Sunday April 25, 2004 @07:38PM (#8968326)
    I don't know about that, but I have in fact done testing and C# is slower at almost everything when compared to C/C++ and it gets really bad at the high end.

    I don't know what 'benchmarks' you used to come up with that conclusion. There was a previous /. post [] about programming language benchmarks and the study's results [] are nicely tabulated.

    In this study, C# came in 2nd place overall among many common programming languages, after VC++. It even destroyed gcc C in trig calculations, though, got slaughtered by gcc C's 'double' math tests.

    Even with that said, the difference in speed between C# and VC++ for DeDRMS decryption on a reasonably new computer would be so small that the time taken to port the code from C# to any other language would be better spend picking you nose.
  • Re:Written in C# (Score:3, Interesting)

    by DroopyStonx ( 683090 ) on Sunday April 25, 2004 @07:39PM (#8968329)
    I agree 100%. It's sad to see all these ignorant morons blasting C# just because it's a Microsoft technology and pretty much a clone of Java. If anything, this is one of the few GOOD things that Microsoft has actually done.

    Pretty much anyone and everyone who bashes it doesn't have an honest to god FACTUAL reason why it "sucks" so bad, that's the funny part.

    I've worked with both extensively, and while Java definitely has the upper hand in being truly cross platform, C# and the .NET framework is a million times easier to work with.

    People really need to start taking their heads outta their asses before rambling off about something they don't know about.
  • by Cthefuture ( 665326 ) on Sunday April 25, 2004 @08:33PM (#8968674)
    Thanks for the link. I always like to look at what other people have tried. However, I highly doubt those results. Besides, C++ still came out on top.. eh?

    For one thing they don't really test anything useful as the tests are just tight loops of very basic math stuff. His C code doesn't even compile with the VC++ compiler because he's using C99 syntax (Microsoft's compiler is not C99 compliant). And even when I fixed those problems there where a lot of warnings due to questionable variable usage. The C++ version isn't even written in C++, I wonder why there are even two separate files. Not a good start and makes me seriously question this programmers abilities.

    Just a quick glance at the code suggests at least the trig benchmarks are more a test of the standard math library rather than the language. C# is going to use the same version as C/C++.

    His timing methods are also questionable. Using CPU time can be highly inaccurate. It's much better to use the high precision timing functions.

    I will need to take a more detailed look and do some testing of my own to see if these results are valid. Off the top of my head I will say there seems to be something screwy going on because I've never seen properly written code run faster in C#. It's just not possible. C and C++ are so close to the hardware that when written properly it is near impossible to make it faster without going to assembly. The best C# can hope for is something close to C/C++, but never better.

    I'll make another post if I get time to take a more detailed look but I'm not optimistic about these tests being worth anything. Try the Language Shootout [] (or the win32 [] version) benchmarks for broader benchmarks where a lot of them have actually been looked at by programmers that know what they are doing. If you know what you are doing then you might want to really try them, don't just go by the results on the pages because some of them are skewed because the run times are way too short to be meaningful.

    Again, I ask you to design a vector class in C# that uses the same or less memory than C++ and performs the same or better. It's not even close to possible.
  • by Cthefuture ( 665326 ) on Sunday April 25, 2004 @09:49PM (#8969020)
    It's certainly quite possible to design a C# vector class that's both more memory and processor efficient in most cases than C++. Here's how:

    You mean you've implemented this in C#? Or are you saying what you could do?

    Sorry but there's no way to do it in the current C# implementation. You can't even get access to the memory allocators. There is no C# data structure that can tightly pack data in memory while still being dynamic. The best you can do is an array of struct's which is about as efficient as C/C++ but is absolutely not dynamic without causing a ton of overhead (eg. there is no realloc in C#).

    If you can do it in C# then show me some code.

    C++ doubles the amount of space allocated for a vector (or queue, or list, or stack, or dequeue, or binary heap, etc) whenever a resize exceeds the amount already allocated, unless you know enough to tell it to do otherwise.

    You're talking about the default vector allocator. STL is extremely dynamic, you do not have to use to the default allocator if you don't want you. You can be extremely flexible here for whatever you need and design anything you want.

    If you've ever done much benchmarking of the C++ STL, you know that it's usually faster than otherwise identical code written with arrays, which shouldn't be possible, since the array access code can be done fairly easily in assembly without virtual function table lookups and such, but nonetheless is quite real.

    Actually, I have, and you're wrong. So me an example and I'll show you why your array code is slower than the C++ version.

    Virtual function lookups?! Do you even know how the STL is designed or how C++ works? Now I'm not sure why I bothered with the rest of what I wrote above.
  • Re:You're naive (Score:3, Interesting)

    by acamas ( 443784 ) on Monday April 26, 2004 @04:21AM (#8970521)
    I doubt, that there will ever be music without DRM legally available. File sharing makes it in my opinion too "dangerous" for the music industry. Maybe (and I hope that, too) we'll see something like free or "donation music" (in a greater amount than today), but the majority of successfull songs will probably simply stay paid.

    This procedure you're talking about, where a bad law gets passed because a worse one was proposed is in my opinion simply called "compromise" and hence something very important in politics. The fact, that there could be a "worse" DRM comes from the music industry. The users (me too!) don't want any DRM. In this situation, there would be no legal digital music available.

    But having FairPlay there's a compromise: The majority of users (obviously not the people here, but millions of songs have been sold up to now) and the majority of music labels/artists (e.g. not Metallica) are content (not glad) with it. And at least it works.

    Sorry, but saying, that copyrighted material is illegal is not correct (at least not for Germany). Is there a law prohibiting copyright? The only thing we have in Germany is the users' right to make a backup copy. This is possible with FairPlay.

    Just to make my point clear: I'm not at all a friend of DRM. I'm glad about DeCSS to watch movies using linux. I patched my DVD drive to free it from its region code restrictions. But regarding FairPlay: if you think, that it's not the best solution, it's in my opinion still a step to the right direction! Noone stops you implementing a fairer solution, if you can manage to bring the users and the music industry together. But please do not torpedo this first step.
  • by toriver ( 11308 ) on Monday April 26, 2004 @04:50AM (#8970617)
    Apple's DRM Fairplay is rather fair - at least compared to other DRMs.

    That's like saying the Nazi work camps were better than the death camps. They were still concentration camps. (As were the American camps for Japanese-Americans, but that's a different story.)
  • What a load of tosh. (Score:4, Interesting)

    by jotaeleemeese ( 303437 ) on Monday April 26, 2004 @04:55AM (#8970641) Homepage Journal
    Computer code is the way we request that a computer performs a task.

    We don't do it in plain English (or Spanish, Russian, Mongolian or whatever) because we lack the technology (still) to do so.

    If in the future it is possible to program a computer or any other machine with a normal conversation then how the hell are all the ridiculous copyright and patent laws are going to be applied?

    As things stand computer languages are a necessary nuisance to allow people express in a succint and understandable manner their own ideas about how ro solve problems.

    This is perhaps one of the purest forms of speech, which should be mantained unecumbered of patents and covered by fair copyright laws.
  • GPL (Score:3, Interesting)

    by kiwioddBall ( 646813 ) on Monday April 26, 2004 @05:07AM (#8970678) Homepage
    When I click on the link I get a .CS file that says I should have received the GPL license with it - I certainly didn't!

    Is having this link on Slashdot agaisnt the GPL?
  • What worries me most (Score:5, Interesting)

    by BlackHawk-666 ( 560896 ) <> on Monday April 26, 2004 @07:21AM (#8971021) Homepage
    is that over the course of my natural life I will have more than 3 PCs, and this technology is only licensing me to have it on 3 PCs. That means that some 6-9 years down the line (I change PC every 2-3 years) I will have used my DRM encrusted music on all 3 PC's that I am licensed to use and will need some way to authenticate it to the next one.

    Now, project yourself forward 20 years. Will these same profit chasing record companies be willing to provide infrastructure to allow you to move your DRM encrusted music from PC to PC throughout the rest of your exepcted life, and that of your descendants who will inhereit this media? Sure, they'll be happily putting out more music, but are they protecting your previous investments? In the year 2039 when I should be just about ready to breathe my last breathe will I be able to hear all my old favorite albums or will I cark it listening to gangster rap on the radio because my rightfully paid for music isn't authorised for use on my new funky media player.

    This DRM stuff is OK for playing todays tunes, but I worry about the longevity of the media.

Adding features does not necessarily increase functionality -- it just makes the manuals thicker.