payShield 10K Installation and User Guide
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Local Master Keys
Types of LMKs
A
Variant LMK
is a set of 20 double- or triple-length TDES keys, with different "pairs" and variants of those
"pairs" being used to encrypt different types of keys.
Note that the term "pair" is used regardless of whether the LMK consists of double-length keys, or triple-
length keys. The standard LMK format supported in all previous versions of Thales (Racal) HSM firmware
consists of 20 double-length TDES keys.
Note that the term "Variant LMK" refers to the fact that variants are applied to the LMK prior to using the
LMK; a Variant LMK is not itself a variant of any other key.
A
Key Block LMK
is either a triple-length TDES key, or a 256-bit AES key, and is used to encrypt keys in a
key block format. A Key Block LMK is not compatible with a Variant LMK, and it can only be used to encrypt
keys in the key block format.
Note that the term "Key Block LMK" refers to the 'key block' method of encrypting keys; a Key Block LMK is
not itself stored in the key block format.
Multiple LMKs
It is possible to install multiple LMKs within a single HSM. The precise details of the number and type of
installed LMKs are controlled via the HSM's license file:
LMKs are stored in a table within the secure memory of the HSM, with each LMK occupying a different “slot”
within the table. Each slot has the following attributes:
Attribute
Description
LMK ID
A 2-digit number which uniquely indicates the location of each LMK within the
table. All references to LMKs are made by specifying the LMK Identifier.
Key Scheme
•
"Variant" for traditional Racal/Thales LMK – key encryption performed using
the
variant
method.
•
"Key Block" for enhanced security – key encryption performed using the
key
block
method.
Algorithm
•
"3DES (2key)" or "3DES (3key)" is used by Variant LMKs.
•
"3DES (3key)" or "AES (256-bit)" is used by Key Block LMKs.
Other algorithm types may be supported in future software releases.
Status
•
"Test" indicates that the LMK is used for testing purposes.
•
"Live" indicates that the LMK is used for live production purposes.
When installing LMKs, the HSM will prevent any mixing of Test and Live
LMKs within the same slot (i.e. LMK Value and Old/New LMK Value must
have the same status).
Comments
User-entered text, which can be used to help identify LMKs.