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Hi Henrich,
Thanks for your remark. We have to decide the cipher.
For DES/2K3DES we have:
RndA is an 8 byte random number. The sent value is concatenated with RndB’ and decrypted with IV=00…00.
For AES we have:
RndA is an 16 byte random number. The sent value is also concatenated with RndB’ and decrypted but with IV=last block of e(RndB).
On the card side for DES/2K3DES:
The rotated RndA is encrypted with IV=00…00 and sent to the reader.
For AES:
The rotated RndA is encrypted with IV= last block of e(RndA+RndB’).
So my example was for AES cipher and I missed the apostrophe. Thank you.
By the way: the datasheet provides calculated number samples. See chapter 4.1 of the datasheet (MIFARE DESFire EV1, Functionality of implementations on smart card controllers).
The MIFARE Team
Thanks for your remark. We have to decide the cipher.
For DES/2K3DES we have:
RndA is an 8 byte random number. The sent value is concatenated with RndB’ and decrypted with IV=00…00.
For AES we have:
RndA is an 16 byte random number. The sent value is also concatenated with RndB’ and decrypted but with IV=last block of e(RndB).
On the card side for DES/2K3DES:
The rotated RndA is encrypted with IV=00…00 and sent to the reader.
For AES:
The rotated RndA is encrypted with IV= last block of e(RndA+RndB’).
So my example was for AES cipher and I missed the apostrophe. Thank you.
By the way: the datasheet provides calculated number samples. See chapter 4.1 of the datasheet (MIFARE DESFire EV1, Functionality of implementations on smart card controllers).
The MIFARE Team
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