Patrick Gueulle published a logging program (French article) for BasicCards. A BasicCard is a smartcard programmable in a variant of the BASIC language. Patrick’s BasicSPY program logs all APDU requests to a file stored on the smartcard. After using the BasicCard programmed with BasicSPY in a reader, you can retrieve the log file and observe the commands send by the reader to the card.
Patrick’s terminal program to manage the internal file (I translated the menu to English):
A new type of BasicCard was announced in January: the Dual Interface BasicCard. This smartcard also has a contactless ISO14443/A interface. In other words, this smartcard has a HF RFID interface!
This smartcard is handy to make another lowcost RFID detector: I install BasicSPY on my Dual Interface BasicCard and hold it against an (unknown) RFID reader. When the reader supports ISO14443/A , it will send APDUs to the BasicCard which will log them in the internal file. Later retrieval of the internal file reveals the APDUs send to the smartcard:
Didier Stevens 
I work a lot with smart cards and have for about ten years.
I have a DLL hook that replaces scard.dll and logs all the APDUs as well.
Obviously, others have done the same thing.
This, however, is an interesting use for it.
I will have to give it a try.
Comment by oldami — Tuesday 26 May 2009 @ 13:50
[…] Another Lowcost RFID Detector « Didier StevensMar 2, 2009 … The device illuminates an LED upon sensing RFID transmission from a UHF reader, thereby offering a low-cost tool for installers and RFID … […]
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