Hi,
I'd like to start implementing the vnode scope for some of our

file-systems. As with the rest of kauth(9), we'll do so in several

steps, rather than switch all functionality at once.
The first step will be implementing the back-end itself: the scope

definition, some actions (just read/write/execute for now), an

authorization wrapper, and a bsd44/suser simple listener ("if root

or file-system allows then allow") -- see the attached diff.
Once the back-end is in place, I'll follow-up with some more diffs

transitioning various file-systems to use kauth(9) in different places

-- access, chflags, chmod, etc.
Please review. :)
Thanks,
-e.