Mosquitto addon with TLS

How would I go about using TLS with the Mosquitto addon? It appears that it has some key file paths in the configuration, however I can’t work out how to access those files or replace them with my own without having to use the SSH server on port 2222 (which I’d like to refrain from enabling for now, as it appears to be primarily for development usage).

I’ve tried the Configurator addon, but that doesn’t seem to be able to access the filesystems of other addons.