Verify Unload Signature S1 and Generate Unload Signature S2

Command:

Verify Unload Signature S1 and generate Unload Signature S2 .

Field

Length & Type

Details

COMMAND MESSAGE

Message header

m A

(Subsequently returned to the Host unchanged).

Command code

2 A

Value DQ.

*KML

32H or 1A+32H

*KML, encrypted under Variant 2 of LMK pair 04-05.

BIN _IEP

6 H

IEP Issuer Visa assigned BIN.

ID _IEP

10 H

IEP Serial number.

DEXP _IEP

6 H

IEP Expiration date (YYMMDD format).

NT _IEP

4 H

IEP Transaction counter.

M _LDA

8 H

Amount to be unloaded.

CURR _LDA

4 H

Load device currency code.

CEXP _LDA

2 H

Load device currency exponent.

BAL _IEP

8 H

IEP Current balance.

ID _ACQ

8 H

Acquirer BIN.

R

8 H

Random number.

S₁

16 H

Unload request signature for validation.

VKL_IEP

2 H

Optional.  Load Key version. If present but ALGL_IEP not present, then a double length KDL will be used; see Notes in Introduction. Must be present if ALGL_IEP is present.

ALGL_IEP

2 H

Optional. Load Algorithm. Can only take the values 01 and 04. If set to 01 a single length KDL is used and VKL_IEP is ignored. If 04, a double length KDL is used and VKL_IEP is used.

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. Maximum length 32 characters.

Field

Length & Type

Details

RESPONSE MESSAGE

Message header

n A

Returned to the Host unchanged.

Response code

2 A

Value DR.

Error code

2 N

00 : No errors.

01 : S₁ verification failure

03 : Invalid ALGL_IEP

10 : *KML 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.

27 : *KML not double length

S₂

16 H

Returned unload signature.

End message delimiter

1 C

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.