Bypassing Internet Censorship

[Dave]

I'm not talking about filtering or protecting ports, I'm refering to the kind of firewall used to censor content on the web. It'll check the source address against a list of IPs and if it finds it then the host won't be able to connect.

 

Firewalls don't do this, proxies do Firewalls are used for blocking packets at the TCP/IP level, proxies are more high-end.

 

HTTP will censor URLs as well.

 

HTTP is the underlying protocol for the web. Your proxy acts like a HTTP server and client simultaneously, and looks at the stuff it receives from the remote server passing it onto you if it thinks the content is okay.

 

There's nothing in the HTTP protocol that has much to do with content filtering a la web proxy.

[higezzzz]

it depends on wut they use. IF they simply use a keyword watcher or url checker the i.p method will work. In fact it will work on almost all filters. Because they dont block the ip they block the url. The i.p isnt the url so the filter will say "ok" and let u in. Were as normally it would reject the url. Just like in google images, when u type in sumtin bad, thats the keyword checker. and the site, is the url blocker.

[CanadaAotS]

unfortanetly, many big-time proxy blockers (ex. Bess at my school) block the actually IP address, so whatever URL you typed to get there, wont matter

[Dave]

Indeed. A lot of proxies, when given an URL to block, will automatically resolve the name and check the IP address also. It's still not very handy, since if you have multiple domains hosted on one server they all get blocked - annoying to say the least.

[1veedo]

My school has a firewall on IE. My little thumg firefox will resolve sites that IE cannot. And putting the IP in IE will not work. Then there's a sort of proxy that acts as a fireall for the entirety of the ISP! They only want teachers usign their (pretty long) email so they can check on what they're doing. Telent to 25 will work if you find services not on their blocklist. Until recently google worked just fine but that's been added. I really don't know what their ISP thing does...Sometiems if I bypass the IE blocking or am using firefox I'll get "Forbidden" but will not get their gray and red screen. So I'm assuming just the "forbidden" is a message from the ISP and the gray and red screen is sent by the firewall placed on top of IE.

 

All of these can be bypassed by PHProxie, though

[ed84c]

I'm pretty sure its government policy at all schools to have a proxie via the county council which blocks things.

[5614]

Most of the schools in London use the same ISP called LGFL (london grid for learning) which offers a 100MB internet connection, which is pretty kick ass, until you realise its across soo many schools, still, there's about 700 computers in my school and they can all be in use and we still get a decent speed, similar to my 1MB connection at home, although it's hard to tell as I'm not actually downloading which is when you mainly notice it, websites are still quick.

 

Anyway, the point is that yes, this LGFL does run everything through some stupid filter! (Although decent proxies do work).

 

1veedo, do you have to download your proxy, or can you use it through your site?

[1veedo]

You can use it through the site.

 

You can also download the PHPs and host it at your site. I don't think you'd notice the diference but sense I'm all the way over in WV, hosting it off your connection might constitute faster responses.

[TheGeek]

My school uses Novell and It blocks most of the sites but some proxies still work.

[1veedo]

You mean you get to use Suse at your school? I'm jealus

 

We're stuck with Windows, except for the server...

[TheGeek]

You mean you get to use Suse at your school? I'm jealus

 

We're stuck with Windows, except for the server...

sorry but you misunderstood me,

My school uses Novell Client 4.90 for Windows 2000/XP English,

look it up on google.

 

I wish they used suse, that would be so cool.

[Squintz]

How about converting the site into an image using PHP. PHP has the ability to dynamically create a fairly decent image on the fly. Or you could use something like flash or a java applet to mask the actual content of the site.

 

I like the image idea the best.

[1veedo]

Then it wou;dn't be the actual webpage...and impossible to play games. All you really need to do is send everything through a computer not on the blocklist -- like a proxy. If the headers contain IP addresses that aren't blocked, the content will get through.

[calbiterol]

Use PHP to fake a header, much like faking a referer. Would this work?

 

Plus, proxies do nothing for content filters that get certain catchphrases. You'd have to either A, trick them, B, shut off the sensors, or C, download the contents of the page and put them in something that isn't blocked - like word. You can type anything into word - they don't have keystroke capture (I hope they don't) at most schools.

[calbiterol]

Oh here's another idea, install linux to a CD and boot from it. And/or, firefox on a thumb drive.

[1veedo]

I've tried both. Like I said above, if I use another browser I don't get the gray and red screen saying "Restricted...useless bs" but I get black letters sayign "Forbidden."

 

The PHProxy I found just takes the data and creates headers for everything. Images are linked through the script, falsh, everything. And it makes its own headers. You can check out the source if you like. It's actually pretty short and simple -- I just wasn't aware PHP could do that.

 

Edit:

 

Actually, on my old 95 box I'm thinking about using bootcd so I can install Debian and make it look as much XP as I possible can This way I can boot into my custom LiveCD and do whatever the hell I want!

[calbiterol]

That's what I was talking about. Install linux to a boot cd. Instant freedom. I'm doing this for next year. It's going to be fun to replace my school's restricted suckiness with Linux. Hopefully, it'll work.

[TheGeek]

It wont work at some places. At my school the sites are blocked before they even get to the computer. It does not matter what os or browser you try.

[calbiterol]

Well, interestingly enough, I've discovered that my school is in the process of installing wireless hotspots...