3Des - VeriFone MX800 series Programmer's Manual

IPP MS DUKPT C
AND OMMUNICATIONS
IPP7

3DES

286
M X 800 S P
ERIES ROGRAMMERS
P
ACKETS
•
KLK is present and cipher text is being loaded that is encrypted with the
previous KLK, has the correct key version and the key attribute is not equal to
"KEK", the IPP returns an error.
•
KLK is present and cipher text is being loaded that is encrypted with the
previous KLK, has the correct key version and the key attribute is equal to
"KEK", the IPP stores the KLK and its attributes.
•
KLK is not present and cipher text is being loaded that is encrypted with the
previous KLK, has the correct key version, the key attribute KEK value has no
effect, the IPP returns an error.
All 3DES key loads are in GISKE format. 3DES master keys are loaded in clear
text without cryptographic protection if the KLK present flag is clear in the IPP.
The MAC value is all zero bytes. The version of the incoming key is checked
against the stored version. The version of the stored key is the version carried in
the GISKE message. The stored key attribute is set to that in the GISKE
message.
3DES master keys load in cipher text under the protection of the KLK if the KLK
present flag is set. The KLK must be 3DES. The version of the key is checked
against the stored version. The version of the stored key is the version carried in
the GISKE message. The stored key usage attribute is set to that in the GISKE
message.
The rules for 3DES are:
•
KLK is present (the current key attribute register in the IPP is GISKE format)
and clear text 3DES master key is being loaded, the IPP returns error
•
KLK is not present (the IPP KLK present flag is clear) and clear text 3DES
master key is being loaded, the IPP stores the 3DES key
•
KLK is present (the current key attribute register in the IPP is GISKE format)
and cipher text 3DES master key is being loaded with an incorrect key
version, the IPP returns an error
•
KLK is present (the current key attribute register in the IPP is GISKE format)
and cipher text 3DES master key is being loaded with the correct key version,
the IPP decrypts and stores the 3DES key master key attribute equal to the
GISKE format length and equal to 3DES
•
KLK is not present (the IPP KLK present flag is clear) and cipher text 3DES
master key is being loaded, the IPP returns an error
G
UIDE