Allow access to specified IP and IP ranges in v.4?

I'm trying to migrate a site that was running amember 3 to a new server and amember 4. We sell IP based access to companies, in addition to the single user accounts managed by amember. The old site had a plugin that provided a text box on the plugin settings page where we could enter IP addresses and IP ranges, as well as an optional note to remind us which company the IP belonged to. If someone accessed a new_rewrite protected folder from one of those IP's, they were granted access without an amember login.

I don't know where the old plugin came from, but I wonder if anything similar exists for v.4 or if it's at all possible to adapt the old plugin (which I've attached)?

Any progress on this? I am facing the same problem and cannot migrate to version 4 without IPaccess