I am looking for a way to get a fast OpenVPN connection out through a restrictive firewall (this is not a workplace and I am not breaking any code of conduct).
Currently I'm using port 443 direct to the openvpn server, as the firewall allows arbitrary TCP on this port. No ports besides 80 and 443 are open (TCP only) and DNS is internal. However, port 443 has a speed limit of 15mbit/s applied, and is extremely unreliable (openvpn link will fail completely every few minutes).
I've thoroughly tested and come to the conclusion that port 80 will only allow traditional HTTP requests - anything involving CONNECT or Transfer-Encoding: Chunked will be silently dropped.
The ping is low enough (5-10ms) and speed high enough (70mbit down, 15mbit up) that I'm genuinely ready to consider a HTTP polling tunnel (or some wizardry that sets a massive content-length and fires down loads of dummy data), but the problem is that I can't find one. Does any solution for this exist already?
I've tried the generally recommended http://sourceforge.net/projects/http-tunnel/, but no joy as it requires chunked encoding.
Edit: Found a semi-solution - http://www.targeted.org/htthost/. Works but unfortunately too slow in terms of latency to really do much with. Interestingly before I put it behind nginx, by opening its internal URLs I was able to see the default page of the transparent proxy I'm behind (wampserver apache apparently).