[tor-dev] License of TorDNSEL (was: Haskell packages?)

Nick Mathewson nickm at alum.mit.edu
Sat Jun 8 16:25:44 UTC 2013

On Sat, Jun 8, 2013 at 11:58 AM, Nikita Karetnikov
<nikita at karetnikov.org> wrote:
>> There is exactly one such program:
>> https://www.torproject.org/tordnsel/dist/
>> On the bright side (for you, not for us) TorBEL never replaced it. We
>> still use TorDNSEL to generate the exit-addresses files:
>> https://exitlist.torproject.org/
> I've found out that TorDNSEL is in the public domain (see [1]).  It's
> OK, but I'm afraid that my (future) work will be proprietarized [2].
> I'd prefer to relicense the whole thing under the GPLv3+ [3].  So
> TorDNSEL will stay free software [2].  What do you think?

There's a tradeoff that you need to consider with licensing decisions.
 If you pick a permissive license, then there's a risk that somebody
might do a proprietary fork.  This seems to be a higher risk with some
kinds of software than others: I don't personally think that there's
much likelihood that somebody would try to make non-free changes to
TorDNSEL.  (After all, nobody has tried to make non-free changes to
the current version in the past N years.)

If you pick a restrictive copyleft like one of the GPL licenses, on
the other hand, then nobody can, but other free software projects that
have chosen other licenses won't be able to use your code.  For
instance, if you pick GPLv3, then no project that links OpenSSL can
use your software. If you write some interesting bit of Haskell code
that a BSD-licensed Haskell project would like to use, they well
probably sigh and choose not to use it, even if they would really like

So when you pick a copyleft-style license, you prevent non-free forks
at the expense of also preventing a large number of free uses of your

Personally, I would leave it public domain (probably via a CC0-style
statement), or put it under a permissive license (most of Tor is under
3-clause BSD).  My reasoning is more or less that I don't see a big
commercial market here that would *want* to rip off  TorDNSEL. But
this is one of those issues where reasonable people will disagree and
in my opinion it's fine to let the programmers decide.

I'm not qualified to answer your legal question about the force of the
public domain dedication on the code as it stands.

best wishes,

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