Wireshark · Wireshark-dev: Re: [Wireshark-dev] GPL license question

["Abhik Sarkar" <sarkar.abhik@xxxxxxxxx>]

Doesn't developing a dissector or a plug-in for wireshark always
involve including/linking code from the core of wireshark? That would
make any plug-in a derivative work of wireshark which is GPL'ed and
hence the derivative work must also be distributed under GPL?

On 7/11/07, Fulko.Hew@xxxxxxxxx <Fulko.Hew@xxxxxxxxx> wrote:
> wireshark-dev-bounces@xxxxxxxxxxxxx wrote on 07/11/2007 10:45:27 AM:
>
> > No, you can't keep the code for you nor limit the distribution of the
> > plugin object code. It is the basic principle of the GPL. If you're
> > distributing/selling your plugin, you have to distribute the code. And
> > everyone receiving (paying for) this code may distribute it again and
> > again ... without your permission :)
>
> Actually, I'd dissagree.  With GPL v2, there is a clause that a
> developer can invoke if they write their code appropriately,
> and if the 'infrastructure' can support it.
>
> GPL 2 Section 2 paragraph 2, 3 and 4 cover this aspect.
> (Note GPL v3, no longer appears to have these clauses.)
>
> Basically...
> a) if the infrastructure can support 3rd party code invoked
>    dynamically at run time, and
> b) if the infrastructure does not 'depend' on the 3rd party
>    code for its operation, and
> c) if your code is not statically linked with GPL'ed code
>
> then you can release a binary-only version of your code without
> providing source.
>
> So to paraphrase:
> - if Wireshark isn't linked with your code, and
> - Wireshark can still function without your code, and
> - your code isn't linked to GPL'ed code, and
> - someone can replace your code with an equivalent (but seperately
>   developed) module
> then your OK.
>
> FYI. Those paragraphs state:
>
> "These requirements apply to the modified work as a whole.
>  If identifiable sections of that work are not derived from
>  the Program, and can be reasonably considered independent
>  and separate works in themselves, then this License, and
>  its terms, do not apply to those sections when you distribute
>  them as separate works. But when you distribute the same
>  sections as part of a whole which is a work based on the
>  Program, the distribution of the whole must be on the terms
>  of this License, whose permissions for other licensees extend
>  to the entire whole, and thus to each and every part
>  regardless of who wrote it.
>
>  Thus, it is not the intent of this section to claim rights or
>  contest your rights to work written entirely by you; rather,
>  the intent is to exercise the right to control the distribution
>  of derivative or collective works based on the Program.\
>
>  In addition, mere aggregation of another work not based on the
>  Program with the Program (or with a work based on the Program)
>  on a volume of a storage or distribution medium does not bring
>  the other work under the scope of this License."
>
>
> > Jon Andersen wrote:
> > > I'm concerned about the requirements of the GPLv2 license.
> > >
> > > If I write a plugin for Wireshark, which compiles to a plugin DLL only,
> > > and then I distribute the plugin DLL, am I required by the GPL license
> > > to distribute the source (and for anyone I distribute it to, they can
> > > redistribute the source even if I don't want them to)?
> > >
> > > I'm wondering if I can legally distribute only the plugin DLL (and
> limit
> > > the distribution of it), and not distribute the source at all.
>
>
>
> This document is strictly confidential and intended only for use by the addressee unless otherwise stated.  If you are not the intended recipient, please notify the sender immediately and delete it from your system.
>
>
> _______________________________________________
> Wireshark-dev mailing list
> Wireshark-dev@xxxxxxxxxxxxx
> http://www.wireshark.org/mailman/listinfo/wireshark-dev