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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?"

6 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. 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.

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    C - A language that combines the speed of assembly with the ease of use of assembly.
  3. 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.

  4. 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.

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    Punctanym: alternate spelling of words using punctuation or numerals in place of some or all of its letters; see 'leet'
  5. 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...