NTAG 424 AuthenticateEV2First RndA not matching

[shaghayeghnz]

Hi,

I am currently developing an application using Flutter to write to an NTAG424 DNA NFC tag; however, I am encountering some issues with AuthenticateEV2First. I get the correct response 9100h but my RndA is not matching with the RndA that I generated.

for instance my generated RndA is 13c5db8a5930439fc3def9a4C675360f. The D(K0 , TI || RndA´ || PDcap2 || PCDcap2) is d8e5fa458b297bedbdc3f3d3d81a09b4746b8598fbaf31afd8afc24623eb2e2. As you can see the RndA' does not match with the one I generated.

p.s. My decryption method works correctly with the examples in https://www.nxp.com/docs/en/application-note/AN12196.pdf

Best regards, Shaghayegh.

[KellyLi]

Hello @shaghayeghnz 

Please try the following steps:

Step 1: Field On + RF Reset + Activate Idle + RATS+PPS

Step 2: Originality signature verification

Step 3: ISO SELECT NDEF Application

Step 4: Get File Settings

Step 5: GetVersion

Step 6: AuthticateEV2First ( key store by key 0 = 00000000000000000000000000000000)

BR

kelly