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%include "default.mgp"
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Enforcing the GNU GPL
Copyright helps Copyleft
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by
Harald Welte <laforge@netfilter.org>
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GNU GPL - Copyright helps Copyleft
Contents
Introduction
The GNU GPL Revisited
Motivations for licensing under the GPL
Enforcing the GNU GPL
Thanks
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GNU GPL - Copyright helps Copyleft
Introduction
Who is speaking to you?
an independent Free Software developer
who earns his living off Free Software since 1997
who is one of the authors of the linux kernel firewall system called netfilter/iptables
who IS NOT A LAWYER, although this presentation is the result of dealing six months with lawyers on the GPL
Why is he speaking to you?
because he became aware of copyright (copyleft?) infringement and took legal action within German jurisdiction
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GNU GPL - Copyright helps Copyleft
What is copyrightable?
The GNU GPL is a copyright license, and thus only covers copyrighted code
Not everything is copyrightable (German: Schoepfungshoehe)
Small bugfixes are not copyrightable (similar to typo-fixes in a book)
As soon as the programmer has a choice in the implementation, there is significant indication of a copyrightable work
Choice in algorithm, not in formal representation.
Apparently, the level for copyrightable works is relatively low.
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GNU GPL - Copyright helps Copyleft
The GNU GPL Revisited
Revisiting the GNU General Public License
Regulates distribution of copyrighted code, not usage
Allows distribution of source code and modified source code
Allows distribution of binaries or modified binaries, if
The license itself is mentioned
A copy of the license accompanies every copy
The complete source code is either
included with the copy
made available to any 3rd party
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GNU GPL - Copyright helps Copyleft
Complete Source Code
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"... complete source code means all the source code for all modules it contains, plus any associated interface definition files, plus the scripts used to control compilation and installation of the executable."
Our interpretation of this is:
Source Code
Makefiles
Tools for generating the firmware binary from the source
(even if they are technically no 'scripts')
General Rule:
Intent of License is to enable user to run modified versions of the program. They need to be enabled to do so.
Result: Signing binaries and only accepting signed versions without providing a signature key is not acceptable!
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GNU GPL - Copyright helps Copyleft
Derivative Works
What is a derivative work?
Not dependent on any particular kind of technology (static/dynamic linking, dlopen, whatever)
Even while the modification can itself be a copyrightable work, the combination with GPL-licensed code is subject to GPL.
No precendent in Germany so far
As soon as code is written for a specific non-standard API (such as the iptables plugin API), there is significant indication for a derivative work
This position has been successfully enforced out-of-court with two Vendors so far (iptables modules/plugins).
Result
Position of my lawyers and IBM lawyers:
In-kernel proprietary code (binary kernel modules) are not compliant
Case-by-case analysis required, especially when drivers/filesystems are ported from other OS's.
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GNU GPL - Copyright helps Copyleft
Confusion about the GPL
Unfortunately, the wide misconception about copyright, free software, public
domain (even the RedHat CEO!) leads to people unknowingly, or even wilfully
only benefit from the freedom but not fulfill the obligations of the GPL.
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GNU GPL - Copyright helps Copyleft
Enforcing the GNU GPL
Enforcing the GPL
GPL violations are nothing new, as GPL licensed software is nothing new.
However, the recent Linux boom
The FSF enforces GPL violations of code on which they hold the copyright
silently, without public notice
in lengthy negotiations
During 2003 the "Linksys" case drew a lot of attention
Linksys was selling 802.11 WLAN Acces Ponts / Routers
Lots of GPL licensed software embedded in the device (included Linux, uClibc, busybox, iptables, ...)
FSF led alliance took the 'qiet' approach and it took about four months until the full source code was released
Some developers didn't agree with this approach
not enough publicity
violators don't loose anything by first not complying and wait for the FSF
four months delay is too much for low product lifecycles in WLAN world
So the netfilter/iptables project started to do their own enforcement in more cases coming up
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GNU GPL - Copyright helps Copyleft
Enforcing the GNU GPL
Enforcing the GPL
chronological order
reverse engineering of firmware images
sending the infringing organization a warning notice
wait for them to sign a statement to cease and desist
applying for a preliminary injunction if they don't (max 4 weeks after reverse engineering)
Success so far
amicable agreement with Asus, Belkin, Allnet, Fujitsu-Siemens, Siemens, Securepoint, U.S. Robotics, ...
some of which made significant donations to charitable organizations of the free software community
preliminary injunction against Sitecom, Sitecom also lost appeals case
more settled cases (not public yet)
negotiating in more cases
public awareness
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GNU GPL - Copyright helps Copyleft
Enforcing the GNU GPL
Enforcing the GPL
remains an important issue for Free Software
will start to happen within the court
has to be made public in order to raise awareness
Problems
only the copyright holder (in most cases the author) can do it
users discovering GPL'd software need to communicate those issues to all copyright holders
The http://www.gpl-violations.org/ project was started
as a platform wher users can report alleged violations
to verify those violations and inform all copyright holders
to inform the public about ongoing enforcement efforts
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GNU GPL - Copyright helps Copyleft
How to make later enforcement easy
Practical rules for proof by reverse engineering
Don't fix typos in error messages and symbol names
Leave obscure error messages like 'Rusty needs more caffeine'
Make binary contain string of copyright message, not only source
Practical rules for potential damages claims
Use revision control system
Document source of each copyrightable contribution
Name+Email address in CVS commit message
Consider something like FSFE FLA (Fiduciary License Agreement)
Make sure that employers are fine with contributions of their employees
If you find out about violation
Don't make it public (has to be new/urgent for injunctive relief)
Contact lawyer immediately to send wanrning notice
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%page
GNU GPL - Copyright helps Copyleft
Thanks
Thanks to
Alan Cox, Alexey Kuznetsov, David Miller, Andi Kleen
for implementing (one of?) the world's best TCP/IP stacks
Paul 'Rusty' Russell
for starting the netfilter/iptables project
for trusting me to maintain it today
Astaro AG
for sponsoring parts of my netfilter work
Free Software Foundation
for the GNU Project
for the GNU General Public License
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The slides of this presentation are available at http://www.gnumonks.org/
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The netfilter homepage http://www.netfilter.org/
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The http://www.gpl-violations.org/ project
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