Xerox Multi-Function Device Security Target43Copyright 2013 Xerox Corporation. All rights reserved.FAU_STG.1.2: The TSF shall be able to prevent unauthorizedmodifications to the stored audit records in the audit trail.6.3.1.4. FAU_STG.4 Prevention of audit data lossHierarchical to: FAU_STG.3.Dependencies: FAU_STG.1 Protected audit trail storageFAU_STG.4.1: The TSF shall overwrite the oldest stored audit recordsand [generate an email warning at 90%] if the audit trail isfull.6.3.2. Class FCO: CommunicationThere are no Class FCO security functional requirements for this ST.6.3.3. Class FCS: Cryptographic support6.3.3.1. FCS_COP.1 Cryptographic operationHierarchical to: No other components.Dependencies: [FDP_ITC.1 Import of user data without securityattributes, orFDP_ITC.2 Import of user data with security attributes, orFCS_CKM.1 Cryptographic key generation]FCS_CKM.4 Cryptographic key destructionFCS_COP.1.1 The TSF shall perform [the cryptographic operationslisted in the Cryptographic Operations column of Table25] in accordance with a specified cryptographicalgorithm [the cryptographic algorithms listed in theCryptographic Algorithm column of Table 25] andcryptographic key sizes [the cryptographic key sizeslisted in the Key Sizes (bits) column of Table 25] thatmeet the following: [the list of standards in the Standardscolumn of Table 25].Table 25: Cryptographic operationsCryptographicOperationsCryptographicAlgorithmKey Sizes(bits) Standards & Certs.*Symmetric encryption anddecryptionTriple DES (CBC) 168 FIPS 46-3 (cert #826and #1174)AES (CBC) 256 FIPS 197 (cert #1131and #1821)