Disable downloading files


I have a self-hosted RocketChat example. I need to disable downloading files for external devices. But for devices in internal area it should be enable.

Are there any options to do this? I was thincking about one more database (file storage) but didn’t find any information about how to have two DB for one RocketChat.
Another idea is to have 2 RocketChat servers (the first one for internal, another one for external use), but settings have only “upload” parameters not “download”.
Can you help me please?