Re: kernel.org status: establishing a PGP web of trust

Jon Masters
2011-10-08T05:06:30Z

On Fri, 2011-10-07 at 12:29 -0400, Valdis.Kletnieks@vt.edu wrote:
> On Fri, 07 Oct 2011 00:16:01 +0200, Krzysztof Halasa said:
>
> > > Wouldn't the fact that I attend the keysigning party and claim that I was
> > > the owner of key B4D3D7B0, and then subsequently signing your key with
> > > that same key, prove that I actually controlled key B4D3D7B0?
> >
> > I don't think it's needed. Alice claims ownership of key B4D3D7B0, gets
> > signatures on B4D3D7B0 public key. Bob (who actually controls B4D3D7B0)
> > reads Alice's mail and signs something "in Alice's name". Alice loses.
>
> You got that 180 degrees out of phase. Jon said he wanted a keysigning party
> where I would prove that I own key B4D3D7B0 (which is, in fact, my key) by
> signing something random. My claim is that if I can take Jon's key and sign it
> with B4D3D7B0, that's already proving I control the key, and another signing
> of something else doesn't prove anything regarding my control of the key.

What I'm saying is that unless you sign something (random text, my
actual key(s)) in my presence, I can't actually know it was you I was
dealing with or someone else claiming to be you (or your identity).

I see all these keysigning parties where people dutifully check IDs they
don't really know how to recognize and am always struck by how the
offline post-event nature effectively never proves the person you met in
real life is the person whose key you just signed, just that some ID
seemed to reasonably match the name on the fingerprint at the time. I
bet it someone turned up at one of these events with a $100 fake ID made
in China of the kind I hear about on the radio these days, a large
majority of those present would happily sign a key claiming to match
that ID after the event, even if the real owner was never there.

Jon.