Who has jurisdiction over the moon?

I'm curious...has jurisdiction over the moon been hashed out to any degree? Should a country or private industry wish to set up bases, mine resources, etc. may they do so with impunity? While I don't foresee such events happening in the very near future I'd imagine that they certainly will...perhaps even in our lifetimes. Clearly only a handful of countries/consortiums will be technologically/financially capable of such a feat. Will they and they alone dictate what occurs? I'm also curious about the aforementioned questions in re: to Mars.
Anyone here have facts? Opinions?

Officially, I believe that according to international law the Moon belongs to everyone and no one -- that is, no one can 'claim' it to be part of their country, etc.

Of course as a practical matter it would probably really fall upon the United Nations (through the NASA, ESA and/or whatever other space agencies exist in cooperation with the military) to enforce this when the time came should some rogue state or band of prospectors try to set up their own little lunar regime.