Tunneling!

al salamo 3lykom

i copied this post from H4ck3rz forum

It's really INTERESTING


ah ... w hayenfa3 el nas elly fel madeena awy!

Break your Firewall And Proxy Rules

Written By CoderMan
Oct 5 2004

This tutorial will explain

1). How to use Yahoo Messenger blocked by firewall or proxy.
2). How to use MSN Messenger blocked by firewall or proxy.
3). How to use IRC blocked by firewall or proxy.
4). How to use FTP blocked by firewall or proxy.
5). How to use ICQ blocked by firewall or proxy.
6). How to use Telnet blocked by firewall or proxy.
7). How to use P2P software like Kazza, Edonkey blocked by firewall or proxy.
. Other applications which cannot use proxy.

Most
of the companies allow only website surfing (i.e. port 80), but they
restrict all other ports so the employees cannot accesses Messengers
P2P ftp server etc. But there are some ways out for breaking these
rules set at your firewall or proxy server. One of the ways is to use
HTTP Tunneling technique.

What is HTTP TUNNELING?

"Tunneling" sounds good. The method which we are going to use is almost similar to the literal meaning of Tunneling.

Normal scenario
Take an example using an FTP service.
When you connect to an FTP site using an FTP client packet request will be as below

Source IP : your IP address
Source Port : your computer port
Destination IP : 205.*.*.1 (ftp server you are trying to connect)
Destination Port : 21
DATA : Get file File.zip

Let
us think there is a firewall in your network. Administrator of your
network might have blocked port 21 (normally all outing ports are
blocked other than port 80). So now you cannot accesses FTP server
205.*.*.1.Think if this is the scenario is there any way to bypass your
firewall rule?

Yes you can do it.
Why can't we put up a
middleman which can accept all your port 80 request and translate it to
port 21 request then send it to your FTP server i.e. 205.*.*.1. Now you
are asking the middleman server which you have installed outside the
company to connect to FTP server 205.*.*.1 on port 21 and get the file
you required, send it back it to you. This is HTTP Tunneling.

Now the packet you are sending will be like below

Source IP : your IP address
Source Port : your computer port
Destination IP : Middleman Server IP
Destination Port : 80
DATA : Connect to 205.*.*.1 using port 21 and get file File.zip and send it to your IP

If
the firewall captures this packet it will think that it is a port 80
request for the middleman server. So it is a genuine request and it
will allow it to pass through.

So for doing it you need a two
components one client and a server module. Install client module inside
your company. Install server module (middleman) outside company it can
be your personal PC at your home. Configure your softwares i.e. your
Yahoo messenger or IRC to communicate to your client software
installed. Client software will convert your request in HTTP format and
send it to middleman server. Middleman server i.e. your home PC is
basically a web server with a twist. When client is doing tunneling, it
sends series of HTTP requests to the server. Your company firewall sees
as if you were surfing to some web site, and consciously allows you.
Server module i.e. your PC in turn performs it's half of tunneling and
talks to the target servers.

I am attaching a figure with this Tutorial.

You can get the tunneling software from links below

http://www.http-tunnel.com
http://www.htthost.com/
http://www.nocrew.org/software/httptunnel.html
http://www.codeguru.com/Cpp/I-N/interne ... php/c6209/
http://www.totalrc.net/s2h/index.jsp

This is the modified version of my previous post

By

CoderMan
------------------------------------------------------------------------------
Maybe a little improvement:

Using
ssl tunneling, all your requests will be encrypted so the network
administrator won't be able to determine what you are tunneling
biggrin.gif .

Another advantage is that https for example can
not be proxied without breaking the "SSL chain". Certainly not when
client certificates are used.

You can find stunnel on http://stunnel.mirt.net/

Dieter
------------------------------------------------------------------------------

Dr.Death

use hopster

http://www.hopster.com