Forward all traffic from Android to Ubuntu server running privoxy (iptables)

Question

My university has installed a non-transparent restrictive proxy which allows only traffic through 80 and 443 ports. Currently, I have my android phone (Nexus running CM12.1) pointing to my Ubuntu server running privoxy. Privoxy forwards all requests to the restrictive proxy.

This setup fails when I try to use certain android apps like Skype, Hangouts, Whatsapp which I believe makes use of other ports to connect to their servers. I will like to forward all network traffic generated from my android device to Ubuntu server via privoxy. I wish to perform port forwarding for all connections.

I tried my luck with iptables, but failed. How do I resolve this issue?

PS: I know, Drony, on android can solve my problem. But, I wish to solve it using iptables.

Answer 1

If you are behind a proxy that only permits traffic on ports 80 and 443 then you cannot expect it to forward traffic that uses other ports.

You would need to be able to bypass the proxy, for example by using your mobile network or perhaps tunnel through it with an https-aware VPN tunnel such as OpenVPN.