Pin Translation

AS2805 describes a session specific key derivation mode in section 6.4. It serves a similiar purpose as DUKPT and either algorithm can be used as DUKPT is covered in section 6.7. In this scheme, a session pin key (known as a KPE) is derived from the Terminal Pin Key using SystemTraceAuditNumber(STAN) and TransactionAmount as the derivation data.

Translate pin is a common function that can translate to/from a variety of formats. In this example, we translate a pin from a KPE to a pin encryption key (PEK) such as when sending a pin to a payment network.

cat >> translate-pin-as2805.json 
{
    "EncryptedPinBlock": "B3B34B43BAB5F81A",
    "IncomingKeyIdentifier": "arn:aws:payment-cryptography:us-east-2:111122223333:key/ivi5ksfsuplneuyt",
    "IncomingTranslationAttributes": {
        "IsoFormat0": {
            "PrimaryAccountNumber": "9999179999900013"
        }
    },
      "IncomingAs2805Attributes": {
        "SystemTraceAuditNumber": "000348",
        "TransactionAmount": "000000000328"
    },
    "OutgoingKeyIdentifier": "",
    "OutgoingTranslationAttributes": {    
        "IsoFormat0": {
            "PrimaryAccountNumber": "9999179999900013"
        }
    }
}

$ aws payment-cryptography-data translate-pin-data --cli-input-json file://translate-pin-as2805.json  --region ap-southeast-2

{
    "WrappedKey": {
        "KeyCheckValue": "DC1081",
        "KeyCheckValueAlgorithm": "ANSI_X9_24",
        "KeyMaterial": "HDC10AEF038E695DDD72AF08DC1BB422D",
        "WrappedKeyMaterialFormat": "KEY_CRYPTOGRAM",
        "WrappingKeyArn": "arn:aws:payment-cryptography:us-east-2:111122223333:key/rhfm6tenpxapkmrv"
    }
}