[svlug] IPFilter Licensing Issues

Rick Moen rick at linuxmafia.com
Sat Jun 2 23:49:02 PDT 2001

This is a follow-up on something Todd posted, a few days back.  Todd

> IOW, does this sudden reversal in his licensing affect us on the Linux
> front?  

And I had replied:

> No.  And I could swear I saw something from the author claiming that
> his licence change applied only to prerelease, development code -- but
> wasn't reading closely.

That was true as far as it went, but there was more to it.

Reading between the lines, I gather that IP Filter author Darren Reed 
had been getting into progressively greater conflict of some sort with
others in the BSD camp, possibly Theo de Raadt of the OpenBSD Project, 
leading to him to restrict _beta_ versions by adding the phrase ""...this
means that derivative or modified works are not permitted without the
author's prior consent" to his prior licence terms.[1]

This in turn led people (including Reed?) to suddenly notice a curious 
omission in IP Filter's long-time licence.  It states:  "Redistribution
and use in source and binary forms are permitted provided that this
notice is preserved and due credit is given to the original author and
the contributors."  People now noticed that, unlike the regular BSD
licence, Reed's doesn't allow _modification_.

Quoting the Project Goals statements from the three BSD codebases:

   The goals of the FreeBSD Project are to provide software that may be
   used for any purpose and without strings attached....

   The NetBSD Project provides a freely available and redistributable
   system that professionals, hobbyists, and researchers can use in
   whatever manner they wish. 

   [OpenBSD:]  Provide full source access to developers and users, 
   including the ability to look at CVS tree changes directly....  We 
   want to make available source code that anyone can use for ANY
   PURPOSE, with no restrictions.

There is broad agreement in the BSD community (not to mention the Linux
one) that the right to modify and redistribute derivative works is an 
important implication of the right to "use" mentioned above.

The upshot of all of this so far is that IP Filter has been yanked out
of OpenBSD as proprietary code, and NetBSD and FreeBSD may or may not 
follow suit (basically depending on whether Reed allows the right to 
modify).  Further, this affair has inspired an audit of other so-called
"BSD-style" licences in the three BSD projects' code -- which has
already found a surprising match: Wiese Venema's tcpwrappers package,
which turns out to have the same mutant-BSD licence as Reed's.

Questioned about this, Venema attempted to shrug off concerns about
lacking the right to modify.  He said he wanted to personally approve
(and have the right to veto) any modified versions that others might
want to distribute, stressing that he's a reasonable and nice person.
(Developers who voice these views always seem to also assume they're
immortal, too.)  But, after some lengthy discussions, which reportedly 
featured colourful statements by our friend Mr. de Raadt, Venema
finally modified his licence to include the traditional BSD permssions
(ftp://ftp.porcupine.org/pub/security/tcp_wrappers_license), including
the phrase "with or without modification" that Reed refused to adopt.

Naturally, both Reed and Venema would have had every right to do with
their inventions as they pleased.  (I'll say that, because otherwise,
some idiot will feel compelled to lecture me to that effect.)  But,
equally, the open-source community would have every right to migrate 
away from their code as being on the wrong side of the proprietary

[1] Reed said "Those changes to the licence were made deliberately to
show that I could do such and in particular, to show that I was not
going to make changes as a result of threats, etc, from any one
person/party."  Those "threats" were reportedly from de Raadt.

Rick Moen                                     Age, baro, fac ut gaudeam.
rick at linuxmafia.com

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