How to write my own proxy, anonymizer and host it to help when websites are blocked at work

Question

I work as a contractor/freelancer. At most client sites a lot of websites are blocked. Specifically Gmail and Facebook which I really would like access to while on assignment.

I know there are a lot of proxy/anonymiser websites out there that allow you to use their website to circumvent the website filtering of the business IT policy but most of these sites contain malware, objectionable images and are blocked anyway where I am currently on assignment.

I own a number of domains and would like to write my own proxy/anonymiser and host it on one of these domains to let me access Gmail and Facebook while on client site. The url will be low profile, low traffic so should not get blocked, I can already access the urls now.

How would I go about writing the code for this? also if there are any opensource projects or apps I can run on my webserver that will give me this functionallity I would happily do this/buy this product.

I currently have shared hosting but would consider dedicated/virtual if necessary.

What are the things I need to consider to make this work? I don't mind spending money, time to get this working as I have made a decision to remain contracting for the foreseeable future and this will benefit me greatly.

Thanks.

I know it's probably hard to write this, but can anyone post links to some code that does this as a starting point? I have tried searching but can't find anything, I'm really not sure what search terms to use.

Answer 1

Get yourself a reasonable data package from your mobile phone provider, job done. Since you are a freelancer this will be a more cost effective solution than spending your valueable time building such a thing.

Answer 2

Most proxies get blocked soon. So expect it to be closed soon. When people start using it more then most "blockers" will automatically detect it and start blocking it.

You will get lot of proxy website clones if you search. Check this one too.

Answer 3

Sounds like hard work to write your own. One place I worked, I used GoToMyPC to access my machine at home and browse to any blocked sites from that machine. GoToMyPC was an authorized tool because it allowed people to work from home and didn't haven't firewall implications.

Answer 4

Writing your own proxy is quite difficult (I've tried years ago!). Unless you're actually trying to learn all the complexities, if you just want your own proxy solution you'd probably do fine just installing Squid on your own server with Webmin or something to give an easy configuration interface.

Answer 5

If you own a server on the internet you can install OpenVPN, a VPN that can work over SSL port 443. So all proxies/firewalls have to allow this if they allow any web access at all. Wikipedia link for OpenVPN

I've never tried it myself, just read a lot about it.

Writing to your own proxy is very very hard. You have to stay up to date with latest developments to keep it operational. Especially since a lot of web sites nowadays make heavy use of AJAX, and a lot of URLs are generated in script code, so simple replacement of all href attributes won't work.

But it is a good way to learn a lot about the HTTP protocol and all the latest web technologies ;)

Answer 6

Hi..

this blog may help u to start.

http://techkiddos.wordpress.com/2009/07/04/how-we-developed-a-model-proxy-site-anonymizer-with-asp-net/

[How we developed a Model Proxy site (Anonymizer) with ASP.NET..]

Answer 7

strange mental jump, that, if you do not wish to use somebody else's proxy, you go write your own. Why not just use squid? If you want to do it as an exercise, there are extremely simple java proxy servers around. Just take the source code and slim it down. Not very efficient though. I am not sure if I would want you as a contractor lol

Answer 8

Here's what you need to create a (good) proxy:

1. Request the page (remember that you need to support SSL for facebook!
2. Rewrite any part of the page that contains absolute urls and rewrite them to use your script
3. Parse and rewrite the css
4. Parse/Remove any javascript. You might want to give JS function hooking a shot
5. Echo the page

It's a lot more complicated than you'd think at first.

Here's an example from codeproject.net: http://www.codeproject.com/KB/aspnet/asproxy.aspx

Here's an example of a nice javascript hook if you decide to make your own:

var old_open = window.open;
window.open = function(URL, windowName, features) // overwrite window.open calls
{
URL = "http://example.com/proxy.php?url=" + escape(URL);
return old_open(URL, windowName, features);
};

If this code executes first any future calls to window.open will be rewritten to open up the new window using your script. Of course this won't help with things like window.location but it's a start