As many application amy be running as root and not all systems have selinux available (or sometimes it is available but disabled) we need a way to let some apps have a different behavior than others.

The simplest way is to allow non standard sockets and an evnironment variable that tells the interpose plugin which socket to look at.

The first pair of application to take adavntage of this should be rpc.gssd and the kernel.

We changed the default socket to be /run/gssproxy.sock, but that should instead be a special configuration socket and the default should be returned to /var/lib/gssproxy/public.sock