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scroggyg

Contributor

Registered: 2012-09-07

Posts: 14

Tag Signature iso-1443-A 1K tag

I am investigating a tag which produces the response below from hf search, using the latest iceman software
usb] pm3 --> hf search
?  Searching for ISO14443-A tag...         
[+]  UID: FD C7 5C 23
[+] ATQA: 00 04
[+]  SAK: 08 [2]
[+] Possible types:
[+]    MIFARE Classic 1K
[=] proprietary non iso14443-4 card found, RATS not supported
[+] Prng detection: hard
[=]
[=] --- Tag Signature
[=]  IC signature public key name: NXP Mifare Classic MFC1C14_x
[=] IC signature public key value: 044F6D3F294DEA5737F0F46FFEE88A356EED95695DD7E0C27A591E6F6F65962BAF
[=]     Elliptic curve parameters: NID_secp128r1
[=]              TAG IC Signature: 39E64143241FCF79BACC55405B0E055C80F74BBE764740E8835B2738F3DF6176
[+]        Signature verification: successful
[?] Hint: try `hf mf` commands
If I extract the keys they are all ffffffffffff, and I can make a clone of the card to a Chinese magic card.
The original card has no data in the blocks but the sectors all respond to authentication
My question is what is the tag signature and how is calculated, after a cload to the Chinese card it doesn't produce the signature.
Thanks in Advance

iceman

Administrator

Registered: 2013-04-25

Posts: 9,537

Website

Re: Tag Signature iso-1443-A 1K tag

I suggest reading NXP datasheet for MIFARE Classic 1K / S50 Ev1,     and the section about Originality check.