Deactivate authenticated mode command – MagTek iDynamo MagneSafe V5 User Manual
Page 42

iDynamo MagneSafe V5 Communication Manual
36
Example Activation Challenge Reply Request (Hex):
Cmd Num
Data Len
Data
11
08
8579 8275 2157 3495
Example Activation Challenge Reply Response (Hex):
Result Code Data Len
Data
00
00
Deactivate Authenticated Mode Command
Command number:
0x12
Description:
This command is used to exit the Authenticated Mode command. It can
be used to exit the mode with or without incrementing the DUKPT
transaction counter (lower 21 bits of the KSN). The application must send
the first 7 bytes of Challenge 2 (from the response to the Activate
Authenticated Mode command) and the Increment flag (0x00 indicates no
increment, 0x01 indicates increment of the KSN) encrypted with a variant
of the current DUKPT PIN Encryption Key (Key XOR 3C3C 3C3C 3C3C
3C3C 3C3C 3C3C 3C3C 3C3C).
If the reader decrypts Challenge 2 successfully it will exit the
Authenticated Mode and, depending on the Increment flag, may increment
the KSN.
If the reader cannot decrypt Challenge 2 successfully, it will stay in the
Authenticated Mode until either the time specified in the Activate
Authenticated Mode command passes or the user swipes a card. This
behavior is intended to discourage denial of service attacks. Exiting the
Authenticated Mode by timeout or card swipe always increments the
KSN, exiting Authenticated Mode by the Deactivate Authenticated Mode
command may increment the KSN.
Data structure:
Request Data:
Offset
Field Name
Description
0
Response to
Challenge 2
Seven bytes of Challenge 2 plus one byte of
Increment flag as outlined above, encrypted by the
specified variant of the current DUKPT Key
Response Data: None
Result codes:
0x00 Success
0x02 Bad Parameters – the Request Data is not a correct length
0x03 Bad Data – the encrypted reply data could not be verified
0x07 Sequence – not expecting this command
Example Deactivate Authenticated Mode Request (Hex):
Cmd Num
Data Len
Data
12
08
8579827521573495
Example Deactivate Authenticated Mode Response (Hex):
Result Code Data Len
Data