Command:

To validate an S₆ Message Authentication Code (MAC) calculated by a CEP card on a detailed transaction record.

Notes:

Use of this command requires the optional ESP licence. Error code 67 will be returned if the command is not licensed.

Field

Length & Type

Details

COMMAND MESSAGE

Message Header

m A

Will be returned to the host unchanged

Command Code

2 A

Value “W0”

KMP

32 H

Master Purchase Key, encrypted under variant 3 of LMK pair 20-21

ALGP2

1 B

Algorithm code for S₆ in purchase transactions;

must equal X’10

ID_CEP

6 B

CEP card serial number

NT_CEP

2 B

CEP card transaction number

DEXPP_CEP

3 B

CEP card expiration date for offline transactions

TI_CEP

1 B

CEP card transaction indicator

DTHR_PDA

5 B

PDA transaction date and time

CURR_PDA

3 B

PDA currency

AM_CEP

1 B

CEP card authentication method

RID_PSAM

5 B

Registered identity of the entity assigning PSAM Creator IDs

ID_PSAMCREATOR

4 B

Identifier for the creator of a PSAM

ID_PSAM

4 B

Identifier of a PSAM

NT_PSAM

4 B

PSAM transaction number

MTOT_CEP

4 B

CEP card total transaction amount

M_PDA

4 B

PDA transaction amount

BAL_CEP

4 B

CEP card slot balance

S₆

8 B

Transaction MAC, to be validated

End Message Delimiter

1 C

Optional. Must be present if a message trailer is present. Value X'19

Message Trailer

n A

Optional. Maximum length 32 characters

Field

Length & Type

Details

RESPONSE MESSAGE

Message Header

m A

Will be returned to the host unchanged

Response Code

2 A

Value “W1”

Error Code

2 N

00 - No error

01 – S₆ verification failure

70 – Invalid ALGP2

10 - KMP parity error

12 - No keys loaded in user storage

13 - LMK error – report to Supervisor

15 - Error in input data

21 - Invalid user storage index

End Message Delimiter

1 C

Will only be present if present in the command message. Value X'19

Message Trailer

n A

Will only be present if in the command message. Maximum length 32 characters