[4373] in cryptography@c2.net mail archive
Re: Stego for watermarking Perl5 code?
daemon@ATHENA.MIT.EDU (Jim Gillogly)
Tue Mar 23 13:13:39 1999
Date: Mon, 22 Mar 1999 16:03:33 -0800
From: Jim Gillogly <jim@acm.org>
Reply-To: jim@acm.org
To: cryptography@c2.net
"Shabbir J. Safdar" <shabbir@mindshare.net> skribis:
> So I'm looking to protect some Perl code from the situation where someone
> might break into my site and copy it and start marketing it. ...
> given the relatively free form nature of the language and the
> fact that I can throw in all sorts of comments.
...
> I'm fairly motivated, and could adapt a decent library to a tool (in perl,
> ofc ourse) should one exist. Does anyone have any leads on where I might
> start looking?
I'm not sure comments in general help you. If somebody uses your code
intact, they might as well leave your copyright notice in, since any
reasonable expert witness will identify your code. On the other hand,
if <they> are fairly motivated also, they'll reformat the bejeepers
out of your code and make it much less recognizable. Perl's
flexibility is working against you here, and even an expert may
have trouble convincing a jury that the flowchart graph isomorphisms
demonstrate plagiarism.
If the application lends itself to "magic constants" such as those
used in the initialization of some ciphers and hashes, you could
hash the phrase "All this bumf was written by Shabbir and is by-god
copyrighted!" and use the result of that hash for your magic numbers.
If they're trying to make something that will be compatible with
what you're selling, they may need to use your numbers, and at the
trial you could explain where the numbers came from and they
couldn't. However, going from there to "they stole my code" may
still be a stretch -- they might claim it was reverse engineered.
Sounds like your solution may be application-dependent.
--
Jim Gillogly
Highday, 30 Rethe S.R. 1999, 23:52
12.19.6.0.15, 10 Men 8 Cumku, Sixth Lord of Night
