SSH for web proxying

OpenSSH can be trivially used as a SOCKS proxy. From your machine, simply run

ssh -D 2000 destination -N

to establish the proxy. The -N flag starts the tunnel without running a shell on the other side and is optional.

Then, tell your web browser to use localhost:2000 as a SOCKS proxy. With Firefox, this is in the Preferences/Network/Connection menu. Alternatively, you can use foxyproxy, a plugin that better manages your proxies.

By default, your DNS requests still go directly to your local DNS server. If you wish to change that, you need to tell your web browser to use the SOCKS proxy to resolve names as well; in the case of foxyproxy, that is under Foxyproxy Options/Global Settings/Miscellaneous.

Why would you want to do this? Well, for one, your HTTP traffic is transmitted in plaintext, so if you are on an untrusted network, someone could be snooping all your traffic. By proxying it through a secure link to a known machine, you are preventing other people on that network from seeing your web browsing, possible passwords, etc.

More interestingly, suppose you have an intranet that has some resources that are not available to the outside world. By proxying through a machine on the intranet, you can remotely use those resources; for example, by proxying through a machine on your collage campus, you can use site-licensed resources like paper archives. Alternatively, if you use Amazon's EC2 (for example, in conjunction with Hadoop), you could use the proxy to let you access web services running on your EC2 images without opening up public ports and even using the internal domain names for the machines.