p5df072ev2 NXP Semiconductors, p5df072ev2 Datasheet - Page 5

• Manufacturer Part Number: p5df072ev2
• Description: Mifare Sam Av1
• Manufacturer: NXP Semiconductors

NXP Semiconductors
P5DF072EV2/T0PD4090_SDS_31
Product short data sheet
PUBLIC
7.4.6.1 Key reference number
7.4.3 MIFARE cryptography
7.4.4 Key versioning
7.4.5 Key diversification mechanisms
7.4.6 Key storage
MIFARE keys are stored in the same space as AES and 3DES keys using the following
scheme:
Remark: MIFARE key versions can only be stored for a key pair A and B.
The MIFARE SAM AV1 reserves three bytes in a key entry to store the version of the three
available keys in the entry. This version byte contains the key version for all kinds of keys
(DES, 3DES, AES and MIFARE). The version information must be included separately in
every key entry of type AES or MIFARE when it is updated by the ChangeKeyEntry
command.
A main feature of the MIFARE SAM AV1 allows diversification of any kind of keys (AES,
DES, 3DES and MIFARE).
The following diversification mechanisms are implemented:
The MIFARE SAM AV1 uses a Key Storage Table (KST) in order to store and manage
keys and attributes related to keys.
The KST holds 128 entries. Every entry contains positions to store three (3)DES, two
3key3DES, three AES128, two AES192 or six MIFARE keys plus their attributes.
Every key entry is referred to by its index, the KeyNo.
KeyNo is the index of the entry in the KST and can have the value 00h to 7Fh.
KeyNo 00h is defined as the SAM master key:
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MIFARE standard key A in byte 0 to byte 5 of the 16 byte field
Key number (KeyNo) of the MIFARE standard key diversification key for MIFARE
key A in byte 6 of the 16 byte field
Key version of the MIFARE standard key diversification key for MIFARE key A in
byte 7 of the 16 byte field
MIFARE standard key B in byte 8 to byte 13 of the 16 byte field
KeyNo of the MIFARE standard key diversification key for MIFARE key B in byte 14 of
the 16 byte field
Key version of the MIFARE standard key diversification key for MIFARE key B in
byte 15 of the 16 byte field
Diversification of MIFARE keys using a 3DES key
Diversification of 3DES keys using the key to diversify itself
Diversification of AES keys using the key to diversify itself
The three/two key versions stored in KeyNo 00h are used for host authentication after
reset in case bit 10 of the configuration settings SET of key 00h is set to logic 1
All information provided in this document is subject to legal disclaimers.
Rev. 3.1 — 14 June 2010
189731
P5DF072EV2/T0PD4090
MIFARE SAM AV1
© NXP B.V. 2010. All rights reserved.
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