Technical information

HGST Ultrastar C15K600 Hard Disk Drive Specification
339
21.6
Firmware Download and Signing
The HGST Firmware signing and download for encryption drives is meant to provide a mechanism for secure
updates through the Host interface. Firmware is downloaded to the drive through the host interface, and the
signature is verified using a public key installed in the reserved area during manufacturing, before it is loaded to RAM
or installed in the reserved area on the HDD.
Signature verification uses the RSA-PSS (Probabilistic Signature Scheme) signature verification algorithm with
EMSA-SHA256 as padding function. The firmware was designed and implemented with the intention of meeting
the signing requirements under FIPS 140-2.
All HGST firmware packages will be signed, but only encryption enabled drives will verify the signature. If the
signature cannot be successfully verified on encryption drives, the firmware cannot be downloaded onto the HGST
encryption drives. Failures to authenticate the firmware image will result in Check Condition with KCQ 5/26/9a
(FRU 0). The act of issuing a firmware download to the drive will result in an implicit close of all open sessions at
the security layer.
21.7
Revert Feature
HGST has extended TCG Enterprise to include the TCG Opal Revert method. Revert enables the customer, as
needed by organizational policy, to overwrite existing TCG settings to the default values that were written
during manufacturing.
Revert introduces a new TCG authority, PSID, to the Admin SP. During manufacturing, the PSID is hashed, and
the digest is stored in a reserved area inside the drive. Also during manufacturing, the PSID is printed, in
plaintext, on the drive’s physical, external label. The PSID PIN cannot be accessed via the drive’s interface,
and it cannot be changed.
Below is the procedure to execute Revert:
• Start Session on the Admin SP
• Authenticate to the PSID authority
• Execute the Revert Method
• Successful completion of Revert automatically ends the TCG session
Notes for Revert include:
• Revert execution that encounters an error does not close the TCG session
• Reset of the drive during Revert will cause the subsequent power up sequence to be extended while
Revert finishes its work
Table 289 PSID Authority Added to Admin SP Authority Table
UID
Name
Common Name
IsClass
Class
Enabled
Operation
Credential
00 00 00 09
00 01 FF 01
PSID PhysicalDriveOwner F Null T Password C_PIN_PSID