can we use just OpenPICC to capture communications(record transaction) between Mifare card and genuine card Reader?

[Johannes Schlumberger]

On Thu, Feb 19, 2009 at 01:17:09PM +0000, polychrom at fastmail.fm wrote:

Hello Alex,

> I wish to choose between Proxmark3 and OpenPICC device.
> Just to clarify, what I mean: I want capture and save communication dump
> between Reader and Card for further analyzing in desktop PC, to find a
> secure key. So, in general, I need place OpenPICC unit near the genuine
> Reader terminal(how close), then take Card and make authorization with
> this Reader. Will OpenPICC  capture this communication? If so, does it
> store dump into own internal memory or in laptop?

In theory OpenPICC is capable of such a task. However I myself could not
successfully do so. That is why I ended up using the Proxmark.
The optimal distance between the reader and the sniffingantenna (OpenPICC has an
integrated antenna) depends on the Reader you want to capture the data from. We
found a distance of about 7mm to be optimal. But your mileage may differ.

Proxmark will store the sniffed data on its intermal memory, there is a
Windowsclient available to read and analyze this data (on a desktop PC) which
has been ported to Linux by Michael Gernoth some weeks ago and a link to the
port is postet in the Proxmark community forum. If you are interested I can also
provide you with a Linuxprogram to recover the secret key from a successfull
sniff.

> Then, should I make this communication with genuine Reader terminal
> only, or it possible use Card with any commercial desktop Reader?(and
> the dump of this comunication will also contain Crypto1 key?).

You have to make the communication with the genuine Reader terminal, since only
this terminal holds the secret key you are, after all, interested in. It is not
possile to use another reader to recover the key. You must use a geniune Reader
and a genuine tag to capture the data you need.

regards,
	Johannes


-- 
Johannes Schlumberger                      Department of Computer Science IV
Martensstrasse 1  D-91058 Erlangen Germany  University of Erlangen-Nuremberg
             http://wwwcip.informatik.uni-erlangen.de/~spjsschl