They do not mention sources, but I'd say it is some sort of open secret which is known by a lot of journalists. They mention that this officially does not exist, and from off-the-record talks, it does not exist because it's "secret défense".

From what I've heard, no. This isn't a Snowden leak, it's the result of a journo sitting on information and having an opportune moment to publish.

This isn't the first exposé of the French government's communication surveillance either. There have been quite a few articles on this over the past few years.

It is some coincidence for this to come out the day after the airspace fiasco.