Tin Isles

The article you are reading has moved! It is now available at: http://blog.tinisles.com/2006/03/remote-desktop-sshputty/

If you ever want to open your PC for remote access - but want something relatively secured. Here is a good solution using: OpenSSH, Putty, and public/private key authentication. Putty can access your OpenSSH server via a HTTP proxy on port 443, which is handy if you are behind a firewall (i.e. at work). Took a couple of articles to get it going:

• Connections through Firewall via SSH tunnel
• Configuring OpenSSH (Win32) for Public Key Authentication

Nothing like this works straight away, so here's a logical order of steps to get things going:

• Install OpenSSH on the target machine, and install Putty on a non-firewalled machine somewhere. Go though the steps in the first document, and forget everything about the HTTP proxy stuff. If you can click 'Open' in Putty and see the 'Login:' prompt you're on the right track.

  

  Luckily for me a friend opened up VNC for me on his home machine so I could test this step. If things aren't working here: make sure port 433 is being forwarded on your router (and you ISP doesn't block it!), and you've set up an exception in Windows Firewall to let port 443 in. Experiment with a different port number - make sure you configure the right port number in sshd_config, your router, and windows firewall.
• Now that works try the HTTP proxy bit.
• Happy with that? Now try setting up the public key authentication. I had some troubles here with OpenSSH being very sensitive to config settings. After changing a setting the SSH terminal window (above) wouldn't display anything. Keep a back-up of the config file when it works!

Labels: networking