SSL negotiation protosol in CIFS

Steve Langasek vorlon at
Wed Aug 22 18:36:53 GMT 2001

On Wed, 22 Aug 2001, Michal Trojnara wrote:

> > I do not exactly understand what you mean with "restricted to GPL".
> > GPL does not restrict anything, one of the foundamental rights it
> > provides is the right to study the code and make your own implementation
> > if you want.
> > The only thing not permitted is "stealing" the code (getting it and
> placing it under another licence).

> I'll try to make it clear:
> 1. I wasn't able to find an open specification for SSL negotiation in CIFS.
> 2. I'd like to add CIFS negotiation to my software
> (
> 3. I'm not able to study samba code without accepting GPL license.
>    (nothing else grants me permission to do that)
> 4. Accepting GPL license will make my implementation derived from samba.
>    (based on samba)

a "work based on the Program" means either the Program or any derivative work
under copyright law: that is to say, a work containing the Program or a
portion of it, either verbatim or with modifications and/or translated into
another language.  (Hereinafter, translation is included without limitation in
the term "modification".)

(IANAL, but)

Studying the Samba sources to find out how they do something, then going off
and writing your own independent implementation, does not make your code a
derived work.  The ideas contained within the source code are not copyrighted,
only the implementation of those ideas is.

You do not even have to accept the GPL in order to examine the Samba source
code.  You only need to accept the GPL if you redistribute Samba or its source
code, or works derived from that code.

You may be concerned that your creation of a compatible implementation of
CIFS-over-SSL will be /perceived/ as a GPL violation, and that the copyright
holders on this code might come after you.  Pragmatically speaking, that is a
legitimate concern; and if you're trying to protect yourself against
harrassing lawsuits from Samba Team members, I guess I don't have any
compelling arguments. :)  But in point of fact, you would not be violating the
GPL to look at the source code.

Steve Langasek
postmodern programmer

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