Re: code signing with foreign function interface?

[joakim]

address@hidden writes:

> David Kastrup <address@hidden> writes:
>
>> address@hidden writes:
>>
>>> - We don't necessarily need a complete secure infrastructure for
>>> this. A simple solution might be to check for the presence of a form
>>> of GNU license in binary form in the dll. This particular GNU license
>>> is itself protected by copyright and cannot be combined with other
>>> works without creating a derived work.
>>
>> Useless:
>>
>>      Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>>    
>>   Everyone is permitted to copy and distribute verbatim copies
>>      of this license document, but changing it is not allowed.
>>
>> So you can copy the license into any work you like.  The presence of the
>> GPL as a binary blob is meaningless with regard to licensing.  A book
>> may also print the GPL without becoming GPLed.
>>
>> The GPL becomes relevant only when it is made clear that the acquisition
>> of some software is governed by it.  Its mere presence in some manner is
>> not more than a pointer.  If it is needed as a key without legal
>> meaning, that use is perfectly covered by its license.
>
> Ok, I was unclear. I didn't mean that the GPL in itself would be used for
> this. I meant another new license, derived from the GPL, but specialized
> for this purpose, specifically avoiding the pitfall you describe.
>
> Maybe its still useless, but lets describe each step:
>
> - Define a copyrightable text that might also be used as a binary blob.
> this text has a license that allows it to be bundled with other GPL:ed
> binary blobs, such as GPL:ed dll:s. Since these dll:s are GPL:ed its ok
> to produce a new signed dll with the text in it.
>
> - Sign a dll with this text with some kind of signing tool. Maybe static
>   linking will be enough.
>
> - Emacs FFI loads the dll and checks that the desired licensed text in
>   binary form is present, and then proceeds to use the dll. If the text
>   is not present, refuse to proceed.

Explaining this idea in technical terms wasnt incredibly
productive. Instead, lets ask this question:

- Emacs gets a new FFI facility. When this FFI facility tries to load a
  dll the first time in a session, it asks the user if the dll has a
  valid license. 

That's all. No code signing, no nothing to further prevent the user from
making a mistake. Would this be enough for an Emacs FFI?


-- 
Joakim Verona