[Tfug] Code obfuscators and watermarking

[Jeffry Johnston]

Maybe this will help:

http://freeworld.thc.org/root/phun/unmaintain.html

Another idea is to write an interpreter for your own esoteric (and of
course undocumented)  language.  Then, write your code in that lang.
Apply as many principles from the above site as possible when writing
your interpreter ;)   If you need ideas for your esolang:
http://esolangs.org/wiki/Main_Page

If possible, combine this with things such as self modifying code, or
on the fly decompression of code and/or data.

Another idea (thinking in x86 here for a moment): Make use of
instructions like JMP AX ... so now, they can't just disassemble the
code.. they'll have to put your mess in a debugger and trace through
it.. because otherwise they have no idea where that jump goes to
(gotta love that halting problem).

Basically if you can force them to trace through your code in a
debugger, you've won.. That's the best you can really hope for in the
end (there is no winning.. because if the cpu can run it, someone with
WAY too much free time on their hands can crack it, short of using
some kind of hardware dongle storing a strong encryption key).  Then,
of course, exploit as many debugger weaknesses/bugs as possible.

Or... just skip all that and put the GPL on your code.  Much easier
and more satisfying since other hobbyists can use it too.  That's what
I recommend ;)  Companies have been bitten a lot lately by misusing
GPL code, and I think it's having an effect.

Jeff



On Mon, Apr 7, 2008 at 9:33 PM, Jude Nelson <judecn at gmail.com> wrote:
> If you look at the open-source nv NVIDIA X.org driver, you can see a
>  good example of how to do it :)
>
>
>
>  On 4/7/08, Bexley Hall <bexley401 at yahoo.com> wrote:
>  > Hi,
>  >
>  > Anyone have any *first-hand* experience with
>  > obfuscators for C sources?
>  >
>  > On a related note, experience with non-trivial
>  > watermarking techniques?
>  >
>  > Thnx,
>  > --don
>  >
>  >
>  >
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