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Can Watermarking Help Find GPL Violations?

Posted by timothy on from the why-couldn't-it dept.

bitkid writes "I recently run across techniques that can be used to watermark program code. While I yet have to see some source code for this to play with, the authors claim that the watermarks can be introduced into the source code and can be found in the compiled executable. My question for the slashdot-crowd is: Do you think free software (GPL or other viral licenses) should be watermarked? This could help to find GPL violations (think Everybuddy or Linksys) or can be used in court someday against the next SCO to prove authorship. What might be the ramifications of this?"

15 of 265 comments (clear)

  1. Useful, but easy to get around. by The+Head+Sage · · Score: 5, Insightful

    This would be useful to prove that code is under the GPL, but this could be simply gotten around by just looking at the code, then rewriting it yourself. But, of course this will take time and money, something the big business hate to spend.. But the technology is useful.

    --
    To NULL or not to NULL.
    1. Re:Useful, but easy to get around. by floydigus · · Score: 5, Insightful

      Absolutely right.

      Furthermore, you could automate the process by writing a script to do things like randomising white space, replacing variable names, and even rewriting simple flow control constructs.

      I would suggest that if it is deemed important to be able to establish the originator of the code, then the originator should publish it as theirs as soon as it is written, or at least give it to an independent witness for safekeeping.

      --

      All things in moderation; including moderation

    2. Re:Useful, but easy to get around. by angel'o'sphere · · Score: 2, Insightful


      But the history of copyright law in the UK has tended towards an "If you wrote it then it's yours, now can you prove it?" model, and proving it is a difficult thing to do nowadays if you publish an original work on the net.

      Here we have no national registry of claims of copyright as a matter of public record. Maybe the EU should move towards this model (although I deeply distrust any approach that would actually require registration).
      I disssagree. If you have created something, you usually have kept the interims work pieces, like drafts, first milestones or in case of software, analysis and design documents. Probably you have used a version control system.
      Prooving that yours is yours in cases that matter will be quite easy.
      How often have you heared about "he ha stolen my copyrighted work" cases?
      They rarely happen. Most of copyright cases arise from uncertain ownership or via several countries boarders.
      angel'o'sphere

      --
      Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
  2. Beware the flipside by egg+troll · · Score: 5, Insightful

    I would be very careful with using something like this. Its nice to think that one could use watermarking for protecting GPL'ed code. However, should the technique prove successful, expect to see everything under the sun watermarked by less benevolent entities.

    --

    C - A language that combines the speed of assembly with the ease of use of assembly.
    1. Re:Beware the flipside by Directrix1 · · Score: 3, Insightful

      It doesn't matter what you do to code as far as watermarking goes. If the watermarking method is publicly known than it can be easily changed anyways too look like it was watermarked by someone else. For instance you could watermark your code by having variable length whitespace before your comments or something. But that could easily be changed.

      --
      Occam's razor is the blind faith in the natural selection of least resistance and in universal oversimplification. -- EF
  3. I think not by Espectr0 · · Score: 3, Insightful

    GPL appears to common sense still found in people, and simply decency.

    If the trademark stuff gets too hectic, then maybe this will be needed, but for now i dont think it's needed

    --
    Open Source Java Web Forum with LDAP authentication
    1. Re:I think not by LuxFX · · Score: 5, Insightful

      If the trademark stuff gets too hectic

      If?

      Can I have directions to your hole, I'd like to live there too.

      --
      Punctanym: alternate spelling of words using punctuation or numerals in place of some or all of its letters; see 'leet'
  4. Watermark? by NicenessHimself · · Score: 2, Insightful

    we are talking about a bunch of 1s and 0s here. If it can be watermarked, it can be unwatermarked. A simple script will be able to rearrange stuff to disrupt the watermark without affecting the execution of the program.

  5. as usual by snarkh · · Score: 5, Insightful
    The submitter did not bother to look at the atricle (or rather the presentation).

    The main idea is that you embed the watermark into the code and then obfuscate it. The resulting code is unreadable, otherwise watermark would be trivial to remove, which makes it absolutely useless as far as open source is concerned.

  6. They are talking about Java by HBI · · Score: 1, Insightful

    Wouldn't that have been a nice thing to put in the post text?

    Obviously Java's structure (class files, interpreted code, easy decompilation) makes this easier to accomplish than it would be in C or C++ (or any other language compiled for a particular architecture). It just doesn't make all that much sense for code intended for C compilation, where the source code is freely transmitted. You rewrite out the watermark, it's as easy as that.

    --
    HBI's Law: Frequency of calling others Nazis is directly correlated with the likelihood of the accuser being Communist.
  7. Does it really matter??? by Pedrito · · Score: 5, Insightful

    I wrote a book ages ago about Windows File Formats. Included in the book was some code which was written by a third party. I obtained permission from the code's author to put it in the book, but it was very clearly copyrighted by the author of the code, both in the code, and in the book.

    So Intel is working on a product and they just swipe up the code out of the book, never ask for permission or anything, and use it in a commercial product (VTune). The author of the code, of course, was furious. He approached Intel. They blew him off. He had reverse engineered their code. He could produce an exact replica of the binary with his own code using the MS C compiler.

    He never got anything out of Intel. I suppose he could have hired attorneys, but he wasn't a wealthy guy. He couldn't find attorneys to take it without cash up front. So my question is: How do watermarks help him? I mean the guy could put the binaries side-by-side, and there was no question, it was his code.

    Your code is as protected as the lawyer you can afford...

  8. No, it can't by anthony_dipierro · · Score: 4, Insightful

    Isn't the code itself a watermark? Sure, you can change things here and there, but ultimately the similarities are going to be far to much to be pure coincidence.

    The purpose of digital watermarking seems to be to identify unique instances of the thing being watermarked. So if I have a copy of Britney Spears' album, it's obviously copyrighted by her record company. With watermarking I can get more specific, and see that it was burned from a CD which was sold to Bob Jones. With the GPL this isn't useful. Sure, the code might have been derived from a copy sold to Bob Jones, but he may have legally made a million copies and distributed them around the globe before the GPL was violated, by someone else. You can't control the watermarks, because you can't control the distribution.

  9. The question is SHOULD it be done? by csoto · · Score: 2, Insightful

    ESR and others argue that GPL is "free" as in "free speech." Well, in the United States, we enjoy a lot of this "freedom" (at least until the RWEs are through with us). Much of this has to do with the fact that we go to great lengths to NOT encumber ourselves with systems designed "to get the bad guys." Rather, we depend on a system of mutual responsibility and respect for the law. It's only when an infraction occurs should we seriously consider using effort to detect such fraud. Americans need to be less afraid of their neighbors and demand each other to rise to our expectations.

    --
    There exists no way of exchanging information without making judgments. --Bene Gesserit Axiom
  10. Re: Pointless. by Black+Parrot · · Score: 2, Insightful


    > Does this not go against what open source is all about? It's open code given without the extremes of ownership like water/copy/trade-marks.

    No, all GPL'd code is supposed to be copyrighted. The GPL just grants the user certain rights that are not normally available under copyright law.

    Look at the headers in the source for some of the GPL'd programs on your system, or visit the FSF Web site and see what is recommended for those headers.

    --
    Sheesh, evil *and* a jerk. -- Jade
  11. You missed the point of Free Software by Brandybuck · · Score: 4, Insightful

    Do you think free software (GPL or other viral licenses) should be watermarked? This could help to find GPL violations (think Everybuddy or Linksys)

    You missed the point of Free Software. Ignoring some of the antics of zealous fringe, the idea of "Free Software" isn't to be a separate-but-equal analogue to proprietary software. The point of Free Software is freedom, not surveillance. Too many advocates for Free Software say their contributions are free, but act as proprietary masters with their obsession over owning, controlling and regulating the software.

    It saddens me to see people advocating watermarking Free Software. Next they'll want a "FSSA" analogue to the BSA and their brownshirts.

    --
    Don't blame me, I didn't vote for either of them!