Tunnel over HTTPS

Question

At my workplace, the traffic blocker/firewall has been getting progressively worse. I can\'t connect to my home machine on port 22, and lack of ssh access makes me sad. I was

Answer 1

Find out why the company has such a restrictive policy. It might be for a good reason.

If you still find that you want to bypass the policy, you could write a small proxy that will listen on your server on port 443 and then, depending on the request, will forward the traffic either to your web server or to the SSH daemon. There are two catches though.

1. To determine whether it's an HTTPS request or an SSH request, you need to try to read some data with a (small) timeout, this is because TLS/SSL handshakes start with the client sending some data, whereas the SSH handshake starts with the server sending some data. The timeout has to be big enough to delays in delivering the initial data from the client in the TLS/SSL handshake, so it'll make establishing SSH connections slower.

2. If the HTTP proxy in your company is smart, it'll actually eavesdrop on the expected TLS/SSL "handshake" when you CONNECT to port 443, and, when it detects that it's not an TLS/SSL handshake, it might terminate the SSH connection attempt. To address that, you could wrap the SSH daemon into an TLS/SSL tunnel (e.g., stunnel), but they you'll need to differentiate requests based on the TLS/SSL version in your client request to determine whether to route the TLS/SSL connection to the web server or to the TLS/SSL-tunneled SSH daemon.