policykit.exec mechanism

[Yclept Nemo]

Polkit contains the
"/usr/share/polkit-1/actions/org.freedesktop.policykit.policy" actions
file. Is any accompanying mechanism provided as well?

I am hoping along the lines of:

/usr/share/dbus-1/system-services/*
 - a service file that automatically launches the polickit.exec mechanism
/usr/share/dbus-1/interfaces/*
 - a set of methods the client can request over dbus from the mechanism
/etc/dbus-1/system.d
 - any user is allowed to make a request

The client, started as root user, simply listens for dbus requests,
calls polkitd over dbus requesting "pk_authority.CheckAuthorization",
and if authorized, swaps the euid of the client-requested pids.

Well, probably this mechanism doesn't exist, which is why gksu-polkit
was created...