White Paper

Mode 0: Self-generated Permanent Key, without ATA Password The fictional scenario in the beginning of this white paper depicted SSD devices employing a key management mode lacking an authentication mechanism for encrypted data access. This mode, referred to as Mode 0, uses a self-generated permanent key and operates normally whether installed into its intended host system or any other system. Physical security of guns and guards provides the only data protection with this simple key management mode. A purge of the encryption key in this mode leaves all data permanently encrypted, inaccessible to both adversarial and friendly forces. The data cannot be recovered after the key has been purged. Mode 0 is not a FIPS 140-2 certified mode because there is no authentication. Therefore this mode is not recommended for any military data storage applications. Mercury includes this mode in its secure SSD portfolio to allow basic read/write operations of the drive to be tested for users unfamiliar with the security features of the more advanced modes. Mode 1: Self-generated Permanent Key with ATA Password Mode 1 uses a self-generated permanent key with the added authentication layer of an ATA password. Created by the CO during initial configuration, the ATA password must have high entropy (degree of randomness) for maximum security. The hash of the ATA password, as discussed previously, is stored on the drive and used for authentication every time power is applied to the device. The ATA password is conditioned and then used to encrypt and decrypt the permanent key which remains on the device through power cycles, unless purged by command. This mode is simple to implement and therefore well suited to individuals seeking to protect military data without substantial training in the more advanced key management modes. Because the identity of the self- generated key is unknown to both users and adversaries, it requires no additional infrastructure for protection and distribution of the key. It is important to consider the scenario where the encryption key has been purged, as the key purge option has consequences that cannot be mitigated. In this scenario, the encryption key purge leaves stored data permanently encrypted; the key cannot be refilled by friendly or adversarial forces to access data again. Because of these important security features, Mode 1 can be used to protect data up to the top-secret level in approved CSfC end user device implementations. Mode 1 meets all requirements for FIPS 140-2, CC AA, EE and CSfC- eligible solutions. Mode 2: User-generated Permanent Key and ATA Password Mode 2 employs a user-generated permanent key created by the CO during initial configuration along with the ATA password. The CO must own and manage both values, requiring significantly more resource investment than Mode 1. As such, the CO maintains full authority to change and refill these values into the device at any time. This mode is more complex than Mode 1, as the responsibility for creating key values with high entropy is placed on the CO. However, the end user gains the benefit of data recovery after a key purge event. Like Mode 1, the SSD conditions the ATA password and uses the conditioned value to encrypt the permanent key. No plain text is stored on the drive. During normal operation, the ATA password is needed to decrypt the drive's stored key to decrypt data. The value of Mode 2 is most easily recognized by an example of a common scenario. A secure SSD device storing high-value data must be transported to a new location. Prior to departure from the original location, the key is purged from the drive leaving the data in an encrypted state (with no installed key) ready for transportation. Once the device securely arrives and is installed in a new location, the ATA password and the key are input into the device. Normal read and write operations commence. Under normal circumstances, the permanent key will remain on the drive, encrypted, so the drive will operate normally when accessed with the correct ATA password. If the drive were captured by an enemy in transit, the enemy would require both the key and the password to decrypt the data. Mode 2 meets all requirements for FIPS 140-2 and CC EE. 5 Mode Key Type Key Generation Mode ATA Password Data Recovery After Key Purge FIPS-140-2 Support CC Profiles Supported CSfC-Eligible Requires Guns and Guards 0 Permanent Self No No No EE No Yes 1 Permanent Self Yes No Yes EE AA Yes No 2 Permanent User Yes Yes Yes EE No No 3 Session User No Yes Yes EE No No 4 Session User Yes Yes Yes EE No No 5 Black Key User No Yes Yes EE No No 6 Black Key User Yes Yes Yes EE AA Yes No

• Cover