When I need remote access I nowadays use v9fs+ssh.
Multi-user auth in kernel like you propose sounds nice and consistent,
but too complicated. It doesn't fit linux, and thus an additional
deamon would mean one more place of security relevant code prone to
bugs. And even if this is only intended to be used locally I don't
think it would be good enough for our distributed operating system's
main network protocol.
>From a security (and perhaps simplicity) point of view userspace
authentication sounds more reasonable to me, p9p together with
something like fuse (even together with the new userspace hackery) or
perhaps a single-user v9fs combined with inferno for doing the
auth/crypt work seems a lot more reasonable to me than additional
clever hackery from the plan9 side. Not sure if somebody has something
like this working already...
