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a ssh server running on port 443 and corkscrew kept me sane though my uni years when all traffic to the outside world had to go through their proxy. Once you can ssh somewhere you can set up tunnels and do anything you want

If you can run ssh on a port 443 somewhere, you are as good as outside.

Get corkscrew and use the following in your .ssh/config

host homebox
hostname "fubar.kicks-ass.org" # my old host
port 443
ProxyCommand "~/bin/corkscrew proxy.work.com 80 %h %p ~/.ssh/http_auth"

ssh -D 2080 homebox -v -N and you're all set to rock !. And if you're using firefox, turn on network.proxy.socks_remote_dns and use localhost:2080 as your SOCKS4 proxy (so that your office DNS doesn't get a "A on mail.yahoo.com").

Needless to say, I acquired an intimated knowledge of the network protocol layers and how the different mechanisms in each layer works. I would have never acquired such a clear understanding of DNS lookups & tunneling, if I had been given a wide open network. Now, my current office has only a simplified NAT with port 25 outbound blocked (thank you spamware). But I still need to use this when I go to some campus to talk about something & suddenly miss some image or something from my machine (nearly all campuses in India have strict proxies).

And all this information is provided free of cost, with no liabilities on you getting fired/expelled for using this :)

PS: and somebody should hack CGIProxy to send entity encoded content & accept base64 encoded URLs ;)

Corkscrew is a tool for tunneling SSH through HTTP proxies.

those crazy firewall admins and their rules !

Corkscrew (Unix, Windows) : Tunnel SSH connections through an HTTP proxy.

Curl (Unix, Windows) : Utility who permits to easily download and upload files by using different protocols: FTP, HTTP, HTTPS, Telnet, LDAP, ... Also supports proxies, cookies, authentification, resumes, ...

DesProxy (Unix, Windows) : Tunnel TCP connections through an HTTP proxy, eventually by converting SOCKS requests.

FizzBounce (Unix) : TCP redirector through HTTP proxies.

HTTPort (Windows) [Closed source]: Tunnel TCP connections through the HTTP protocol, by simulating a SOCKS server, and by eventually using an intermediate server.

HTTPTunnel (Unix, Windows) : Bidirectionnal tunnel through HTTP requests, eventually through an HTTP proxy.

LibCurl (Unix, Windows) : Library who permits to easily download and upload files by using different protocols: FTP, HTTP, HTTPS, Telnet, LDAP, ... Also supports proxies, cookies, authentification, resumes, and lots of languages: C, C++, Perl, ...

MultiProxy (Windows) [Closed source]: HTTP proxies tester. MultiProxy can be used as a proxy server who use a different proxy for each request.

Numby (Unix) : Scanner for HTTP vulnerables proxies.

Proxomitron (Windows) [Closed source]: Scanner and redirector through HTTP proxies, who can also delete or modify informations contained in HTML transferred pages. For example, this permits to easily filter automatic popups, DHTML or JavaScript.

ProxyTools (Unix, Windows) : Set of Perl utilities, who permits to use, sort, test and search for HTTP proxies.

TransConnect (Unix) : Transparently tunnel TCP connections through an HTTP proxy.

Zylyx (Unix) : permits to access to files through HTTP proxy caches.

SSL Tunnels are widely used for legitimate transactions, including online shopping and banking. SSL tunnels are SO widely used, that even though they are a feature of corporate firewalls that make it very easy to break through the firewall and essentially ignore all of its rules, and even though corporations are well aware of this risk, they still include HTTPS-proxying because it's so useful to the average person. Others aren't going to clamp down on HTTPS tunnels any time soon either.

I use o2s basic online deal with my laptop. Its evil bad and wrong but I then use Corkscrew to tunnel through their proxy. Its not great (times out after 10mins [1]) but the deal I have has lots of free access, and it keeps me connected when i'm away for a real connection.

I've also used proxytunnel not sure which I prefer.

[1] Fine when using GNU Screen on the remote system

Come on, you have a lower UID than me.
You should be teaching me things.

Ok, ok. Kidding. Sorry.

Check out corkscrew and read this article on the subject.

That should be enough to get you started.

LOL, ya... but its surprisingly hard to block... without a *serious* firewall.

Tools like Proxytunnel and Corkscrew allow you to use an HTTPS proxy server to connect to an ssh server running on port 443... so even most paranoid firewall configurations (no incomming, the only outgoing being http/https traffic, and even then through a proxy server) will allow you to connect to external ssh servers, and from there you can tunnel away.

Friend of mine works at a place which only allows HTTP/HTTPS traffic to pass the proxy. It's not port-based firewalling, it's packet inspection. If it isn't HTTP, it doesn't go thru.

His solution? He developed a java applet which gives him shell access to a Linux box (which also is running a webserver, necessary to serve the applet due to java security). It tunnels over HTTPS to a session running in userspace on the server. He doesn't need root to make it work, either.

There is a much easier solution: use Corkscrew.