Mt Fuji Meeting June 5th/6th, 2007 SecurDisc

Nero action items SecurDisc 1.DUID redundancy 2.Drive and host Revocation 1. Revocation mechanism 1. Authentication 2. Writer application 3. Reader application 2. Updating revocation information 3.Command set changes 1. SecurDisc Feature Descriptor, CPA bit 2. Send Key, Key Format 0

1. DUID redundancy The Disc Unique ID (DUID) is written in an unused Lead-In area. In order to increase the reliability against scratches, defects etc it is written in different ECC blocks.

2. Drive and host revocation Drive and host revocation can be performed in two steps: 1.During authentication process 2.Before reading and decrypting SecurDisc protected user data In order to perform revocation following elements are needed:  Drive Revocation Block (DRB): build in host, used to revoke compromised drives during authentication  Application Authentication Revocation Block (AARB): stored in the drive, used to revoke compromised applications during authentication  Application Revocation Block (ARB): stored in the user data area of the disc, used to revoke compromised applications before reading and decrypting SecurDisc protected user data

2. Drive and host revocation – revocation mechanism 1. Authentication During authentication the drive checks if the application identified by his Application Unique ID (AUID) is valid using the AARB stored in the drive. The host checks if the drive identified by his Device Unique ID (DEVID) is valid using the DRB included in the application.

2. Drive and host revocation – revocation mechanism 2. Writer application Before writing starts, the host writes his build-in ARB into the user data area of the disc and uses the ARB as a key ingredient for encrypting user data.

2. Drive and host revocation – revocation mechanism 3. Reader application In order to decrypt the SecurDisc protected user data on a written disc the host needs to read the ARB from the disc and build a key ingredient for decrypting the user data using the ARB and the Application Unique ID (AUID).

2. Drive and host revocation – updating can revokelocationupdated DRB Drive Revocation Block DriveHost application Update of host application AARB Application Authentication Revocation Block Host application DriveDrive firmware update ARB Application Revocation Block Host application DiscUpdate of host application …which writes an updated ARB on a new disc. Compromised reader applications cannot build the key ingredient for decrypting data.

3. Command Set changes 1. SecurDisc Feature Descriptor, CPA bit Bit Byte (MSB)Feature Code = 113h (LSB) 1 2 ReservedVersion = 0hPersistentCurrent 3 Additional Length = 04h 4 CPA 5 Reserved 6 7 CPA bit will be removed for version 0 (Version = 0) of this Feature Descriptor. Future versions may have this or additional bits in case additional drive features will be added and specified.

3. Command Set changes 2. SEND KEY, Key Format 0 Key Format code definitions for SEND KEY command (Key Class = 21h) Key FormatSent DataDescriptionAGID Use b b Host Key Contribution Send host random number and protocol version Valid AGID required bNone Invalidate Specified AGID. Invalidating an invalid AGID shall not be considered an error. An AGID that has not been granted shall be considered invalid. All other values Reserved In order to be conform with the SEND KEY definitions in Mt. Fuji where each Key Format number of REPORT KEY has a functional equivalent for SEND KEY, we changed the Key Format for Host Key Contribution from b to b.