[ic] Admin permissions system for custom UI

[Grant]

I use a custom admin UI and I need to allow certain users access to
certain admin pages.  My current system consists of a single super
user in access.asc and the following on each of my custom admin pages:

[if-mm !logged_in]
        [bounce page="__UI_BASE__/login"]
[/if-mm]

Does IC contain a permissions system I should be able to make use of
with a custom UI, or am I better off mixing one up myself?

- Grant