Scott O'Brien

Want Free (stolen :P) internet?

Author: Scott O'Brien

DISCLAIMER:  These methods are a thought process only, I have not tried, or shall condone using these methods for stealing internet, only pondering about the methods used of which you may tunnel data through DNS.  If you are going to try these methods out, it’s probably illegal unless you replicate your own private networks to test it on.  Happy surfing

With todays mobile internet being the big thing it is, and not having my ADSL connected just yet, I’ve been borrowing my house mates 3G dongle.  This is a pre-pay service to get internet through the 3G towers.  What the interesting part is when your quota runs out.

Many airports and cafes will provide internet access using an open wireless access point.  While you can connect to these access points, you try and open up a web browser and navigate to a web site, but instead of getting your desired site, you get a page asking you to pay for a limited about of net access.

This generally works as there are a few steps your web browser takes before you can receive a web page.  Generally speaking -> Web browser asks OS to resolve address (google.com for instance) -> OS asks the name server to resolve address -> Nameserver will traverse and ask other nameservers till it gets the address you want -> browser then connects to that address, port 80 and asks for the requested web page… etc

These access points will intercept the traffic to the web host, and instead of returning the web page, will bring up the page asking you to pay money.. note:  You’ve already had outgoing traffic though to resolve that name.

This is where the fun parts come in.  You can have a domain, and delegate a subdomain to another nameserver

so, we can set up our own private server (or a VPS, someone like ramhost.us will do this for $3 a month) then delegate access to a subdomain to it by adding a record to our nameserver:

dnstunner.ourhost.com.    IN    IN    my.vpshost.com

We can then run a little app on this server (see http://www.dnstunnel.de/) and tunnel a TCP connection over DNS requests (although, a little buggy and slow).  Then, the magic begins.  You can tunnel to a HTTP proxy, a VPN over TCP (such as OpenVPN) among other services (such as POP or IMAP, whatever really.)

So, what’s this got to do with getting you free internet?  Well, pre-pay Optus uses the same techniques to direct you to a web page asking you to top up.

Little note:  If you had outbound access to ICMP (ping), similar methods can be used to get net this way

Tags: 3G, OpenVPN, Optus, Tunneling, VPN

This entry was posted on Tuesday, February 2nd, 2010 at 1:34 pm and is filed under Networks. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.