I'd like traffic to be routed via a proxy or VPN based on a the client's hosts file (or DNS that is given to the client).
This doesn't seem like a problem for http traffic on port 80 as a simple squid proxy can do that however I don't know which protocols the client will be sending so I need to proxy all ports.
I have no control over the client apart from hosts/DNS.
Typical Proxy - Can only work for certain protocols/ports
SOCKS Proxy - Works for all but requires client config
VPN - Works for all but requires client config
How can I have a Proxy or VPN that listens on all ports and will act as a transparent endpoint for certain hosts?
Thank you very much in advance.