Despite some hours of Googling, I can't find a solution to this.
Scenario: I need to access my local network (i.e. all devices starting with 192.168.0.x) from the internet.
I have zero router control (ISP locked down).
But, what I do have is: 1) A linux box running inside the local network, connected via an ethernet port to the router.
2) A linux server in the cloud.
I "feel" like the answer is that the local box establishes a connection to the cloud server, and then I connect from my remote workstation to this cloud server, which forms a 'bridge' and lets me then ping/connect/do things to the home network IP's from wherever I am.
I looked at SSH reverse tunnels but that seems to only let me access the single local box - not all devices on the local network via IP.
I also looked at OpenVPN but it seems to only support point-to-point instead of this "bridge" configuration.
All ideas gratefully received - I'm sure it's just my weak google-fu!