Mass import of files and user access permissions?

Hello,
I'd like to know if there is a way to import files (the will already be on the server) and their respective user permissions?

We have 25,000 files and users. One file per user.

I don't necessarily need an interface for the import, and I could do it via an SQL tool. But it will depend on how your table structure, whether it's easy to import a CSV of file names and usernames (users who can access each file).

Obviously, with so many files and users, I need a way to set this up in bulk, either via an interface that's part of the plug-in, or via MySQL directly.

Please advise.