Re: [dm-crypt] license of libcryptsetup (was: verity for GRUB?)

[Milan Broz <gmazyland@gmail.com>]

On 10/11/2012 07:10 AM, Arno Wagner wrote:
> On Wed, Oct 10, 2012 at 03:04:49PM -0700, Geoffrey Thomas wrote:
>> Yeah, if you're planning on looking into relicensing, I'd encourage
>> you to make as much of cryptsetup as you can GPLv2+ instead of
>> GPLv2, so that the code is more reusable in other projects, even if
>> it ends up not being relevant for my specific use case.
> 
> Quick qestion: What is the GPLv2+? I am unable to find any formal 
> references or comparisons, just GPLv2. Pointers appreciated.

Nice list is here
http://en.wikipedia.org/wiki/List_of_FSF_approved_software_licenses
http://www.gnu.org/licenses/gpl-faq.html

Basically, it is shortcut:
GPLvX means GPL version X only, GPLvX+ "... or any later".

And why there is resistance to GPLvX+? Well, "or any later" means
any later. Who knows what is in not yet written GPLv(X+y)? :-)
(And v3 has own problems as well.)

The basic problem is in compatibility matrix, mainly with GPLv3 vs GPLv2
which are not compatible, see http://gplv3.fsf.org/dd3-faq

Because of repeating questions an problems, I would really like to switch
libcryptsetup (IOW cryptsetup library, not binary itself)
to something less restricted (currently most of the code is GPLv2 only).
Perhaps LGPLv2+. But it requires approval from all authors.
(I will perhaps try to get these, otherwise I switch just verity part...)

(TBH, I would myself prefer any new crypto code under even less restricted
licenses like BSD or MIT licence. But cryptsetup already depends on other
GPL libraries, so not sure if it makes sense.
Anyway, if anyone has better idea or any notes here, please let me know.
Now is the best time to complain ;-)

Thanks,
Milan