2
\$\begingroup\$

I wish to be able to read wireless traffic sent from my wireless keyboard. At first I thought I could just buy some board like Arduino, plug in a module like nRF24L01+ and use this combo. Since I'm not good at all with electronics, I'd rather find another solution and, eventually, I thought that I already have a transceiver for wireless comunication: my laptop's WiFi adapter. As I said I don't know much about electronics so I wonder if it's actually possible to write, let's say, a linux device driver for my adapter in order to make it able to capture and process wireless communication other than WiFi. Is there some electronic impediment? Is this just a software problem or maybe my WiFi adaptare firmware won't allow me to read anything except from WiFi traffic?

\$\endgroup\$
  • \$\begingroup\$ Most wireless keyboard use Bluetooth rather than WiFi. BT uses both a different protocol and different radio frequencies from WiFi; the two aren't compatible. \$\endgroup\$ – JRobert Sep 1 '12 at 18:49
  • \$\begingroup\$ I'm pretty sure my keyboard doesn't use BT but, anyway, I'm interested in the subset of keyboards that don't use BT. \$\endgroup\$ – Geeo Sep 1 '12 at 19:10
  • \$\begingroup\$ It may not use Bluetooth, but WiFi also seems unlikely. WiFi is for a much higher throughput than the couple of bytes a keyboard sends, and is a too expensive solution for it. \$\endgroup\$ – stevenvh Oct 1 '12 at 9:51
2
\$\begingroup\$

If it does use the same frequenzy as a wifi card it should be possible depending on your card, skills, and willingness to invest time ;). It might be easier and quicker to go with something else though, look at the path Tim took to make his diy-spy for instance.

Using a device like a wifi spy should answer if it is there or not, Tim made his own diy-spy based on a cheeper device and has published the source code he used. Basing this device on a wifi card should be possible if it supports digital RSSI reporting or not. Starting of at this code it should be possible to find the signal you are intereseted in and working with that.

Another "simple" way to find out what frequency your keyboard uses would be to check it using a Frequency Counter (either borrow from a hackerspace, a friend, a ham or buy one [there are cheap options on for instance ebay]). The reason I say this is that some [I have seen] uses 2.4 GHz, and some 27MHz; and I would be highly impressed if you are able to read 27MHz using a hacked wifi driver ;)

You might wish to check out KeyKerki

This opensource hardware and software project enables every person to verify the security level of their own keyboard transmissions, and/or demonstrate the sniffing attacks (for educational purpose only).

They have done both 27MHz and 2.4GHz but this is a stand alone solution, not using a computer card.

\$\endgroup\$
  • \$\begingroup\$ Thank Jontas for your helpful answer. I'm sure (because I read the specs) that my car use 2.4Ghz, so if I got you right, you suggest to inspect the code written by Tim and use that as a starting point, right? From a "hardware" point of view should this be doable? \$\endgroup\$ – Geeo Sep 2 '12 at 11:19
  • \$\begingroup\$ Inspecting packet traffic with wireshark there's an SSI field in the radiotap header, so my card should support RSSI reporting... anyway I'd be very curious to find a wifi adapter nowdays that doesn't support it, aren't you? \$\endgroup\$ – Geeo Sep 2 '12 at 11:44

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.