Authentication DESFire ev1/ev2: command apdu to respond to the tag challenge

208 Views Asked by At

I'm working on implementing an Android application for authentication with DESFire EV1 and EV2 tags. I've successfully obtained the challenge using the APDU 0084000008 for EV1 and Le=10 for EV2. I've also calculated the response.

However, my problem arises when I attempt to send this response to the tag using an APDU. I've tried several ideas, but I keep encountering errors when sending the response. The APDU command I'm using is as follows:

[0082000008||response] with/without Le

The tag's response is one of the following: 91 1c, 91 ae, or 68 82.

I've also experimented with selecting or not selecting the master application before sending the Get challenge command. In the former case, I receive a 91 00 response for the selection request, but I still face errors when sending the response.

My question is: What is the correct APDU command or procedure to send the calculated response to the DESFire tag? Are there any specific considerations or variations for EV1 and EV2?

I would greatly appreciate any guidance or insights on this issue. Thank you!

I attempted several configurations for interacting with the tag. Here are the steps I followed:

  1. Sent a Get challenge request using the APDU command: [0084000008].

    • Expected outcome: To receive the challenge.
    • Actual outcome: Successfully received the challenge.
  2. Tried to respond using the APDU command [0082000008||response] with and without specifying Le.

    • Expected outcome: Successful response.
    • Actual outcome: Received an error code 68 82.
  3. Also, I attempted to change the APDU commands and followed a procedure outlined in this LinkedIn post, but encountered an error 91 AE after sending the response.

N. B : I've successfully authenticated with the tag using Director V4.50.1 by usin an Elatec reader!

Could you please help me understand what might be causing these errors and how to resolve them?

0

There are 0 best solutions below