* Samuel Henrique: > So now having read a bit more about this whole thing. > > The GPL restrictions do seem quite similar to what the NPSL have, > related to Derivative Works, have a look at this from the FSF > website[0]: > """ > What is the difference between an “aggregate” and other kinds of > “modified versions”? > ... > By contrast, pipes, sockets and command-line arguments are > communication mechanisms normally used between two separate programs. > So when they are used for communication, the modules normally are > separate programs. But if the semantics of the communication are > intimate enough, exchanging complex internal data structures, that too > could be a basis to consider the two parts as combined into a larger > program. > """
An example of such "intimate enough" semantics might be a strictly interpreted serialization format that is only practical to implement by generating code from a formal specification such as Protocol Buffers. For NMAP, there is no 2-way communication. To think that any ad-hoc parser for NMAP's ad-hoc default output format (see below) makes it a derivative work is, in my opinion, laughable. ,---- | PORT STATE SERVICE | 21/tcp open ftp | 80/tcp open http | 139/tcp open netbios-ssn | 445/tcp open microsoft-ds | 515/tcp open printer | 631/tcp open ipp | 5431/tcp closed park-agent | 9100/tcp open jetdirect `---- I have no idea how many such more-or-less such parsers (for the default or the XML-based format) there are in Debian but I'd be surprised if even one of those were NSPL-licensed. >From the reverse dependencies and package descriptions, there are at least: - gnome-nettool - nmapsi4 - some openstack-related packages - OCS iventory - OpenVAS - nikto - brutespray - 2 Python libraries - 1 Perl library - 1 Golang library > The DFSG item 9 is also more about contamination by means of > distribution other than interaction between the tools, as it says: > "The license must not place restrictions on other software that is > distributed along with the licensed software. For example, the license > must not insist that all other programs distributed on the same medium > must be free software." > > Considering both things, I'm inclined to say that the license is > DFSG-compliant. I disagree: The NSPL *does* place such restrictions. Consider the last bullet poiont of section 3: ,---- | * Executes a helper program, module, or script to do any of the above. | This list is not exclusive, but is meant to clarify Licensor's | intentions with some common examples. Distribution of any works | which meet these criteria must be under the terms of this license | (including this Main License Body and GPL), with no additional | conditions or restrictions. They must abide by all restrictions that | the GPL places on derivative or collective works, including the | requirements for distributing their source code and allowing | royalty-free redistribution. `---- I still think that nmap should go to non-free. I believe (but am not sure) that this is unproblematic as long as there is not other software in non-free that is a "derived work" according to the NSPL. Cheers, -Hilko
