Confirmation

Command:

Verify MAC on incoming confirmation message from the terminal.

 

Field

Length & Type

Details

COMMAND MESSAGE

Message header

m A

(Subsequently returned to the Host unchanged).

Command code

2 A

Value RS.

Terminal key register

16 H

The terminal key register encrypted under LMK pair 14-15.

Fields A & B

16 H

The A & B fields from the card as defined in the Racal Security Scheme.

MAC residue

8 H

The MAC residue from the previous message processing; encrypted under LMK 10.

Message length

2 H

Value X’00 to X’A0 (decimal 160) indicating the length of the next field. This field should be set to X'00 and the next field omitted if extended length messages required.

Message text

n A

The response message on which the response MAC should be calculated, but excluding the STX, ETX and LRC. The last 8 characters are assumed to be the MAC. Omitted if extended length messages are required.

Delimiter

1 C

Optional.  Value ";".  Only present if extended length messages to be used.

Extended Message Length

4 H

Optional.  Only present if extended length messages are to be used.  Defines the length of the next field.  Maximum value is determined by the maximum size of the HSM input buffer.

Extended Message Text

n A

Optional.  Only present if extended length messages are to be used. The message to be authenticated as received from the terminal, but excluding the STX, ETX and LRC. The last 8 characters are assumed to be the MAC. An all zero account number cannot be used.  

End message delimiter

1C

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

n A

Returned to the Host unchanged.

Response code

2 A

Value RT.

Error code

2 N

00 : No errors

01 : MAC verification failure

10 : Key register 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

80 : Message length error.

End message delimiter

1C

Present only if present in the command message. Value X’19.

Message trailer

n A

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