Curtiss-Wright Defense Solutions
Compact Network Storage 4-Slot
Software Encryption Layer
(FDEEEcPP20E/FDEAAcPP20E)
Security Target
Version 0.5
04/15/2019
Prepared for:
Curtiss-Wright Defense Solutions
2600 Paramount Pl #200
Fairborn, OH 45324
Prepared By:
www.gossamersec.com
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1. SECURITY TARGET INTRODUCTION........................................................................................................3
1.1 SECURITY TARGET REFERENCE......................................................................................................................3
1.2 TOE REFERENCE............................................................................................................................................3
1.3 TOE OVERVIEW .............................................................................................................................................4
1.4 TOE DESCRIPTION .........................................................................................................................................4
1.4.1 TOE Architecture...................................................................................................................................4
1.4.2 TOE Documentation ..............................................................................................................................5
2. CONFORMANCE CLAIMS..............................................................................................................................6
2.1 CONFORMANCE RATIONALE...........................................................................................................................6
3. SECURITY OBJECTIVES ................................................................................................................................7
3.1 SECURITY OBJECTIVES FOR THE OPERATIONAL ENVIRONMENT .....................................................................7
4. EXTENDED COMPONENTS DEFINITION ..................................................................................................8
5. SECURITY REQUIREMENTS.........................................................................................................................9
5.1 TOE SECURITY FUNCTIONAL REQUIREMENTS ...............................................................................................9
5.1.1 Cryptographic support (FCS)..............................................................................................................10
5.1.2 User data protection (FDP).................................................................................................................13
5.1.3 Security management (FMT) ...............................................................................................................13
5.1.4 Protection of the TSF (FPT) ................................................................................................................14
5.2 TOE SECURITY ASSURANCE REQUIREMENTS...............................................................................................14
5.2.1 Development (ADV).............................................................................................................................15
5.2.2 Guidance documents (AGD)................................................................................................................15
5.2.3 Life-cycle support (ALC) .....................................................................................................................16
5.2.4 Security Target (ASE) ..........................................................................................................................16
5.2.5 Tests (ATE) ..........................................................................................................................................17
5.2.6 Vulnerability assessment (AVA)...........................................................................................................17
6. TOE SUMMARY SPECIFICATION..............................................................................................................18
6.1 CRYPTOGRAPHIC SUPPORT ...........................................................................................................................18
6.2 USER DATA PROTECTION ..............................................................................................................................20
6.3 SECURITY MANAGEMENT .............................................................................................................................20
6.4 PROTECTION OF THE TSF .............................................................................................................................20
7. KEY MANAGEMENT DESCRIPTION.........................................................................................................22
LIST OF TABLES
Table 1 TOE Security Functional Components ......................................................................................................10
Table 2 Assurance Components ...............................................................................................................................14
Table 3 OpenSSL Cryptographic Algorithms.........................................................................................................18
Table 4 kernel Cryptographic Algorithms ..............................................................................................................19
Table 5 libgcrypt Cryptographic Algorithms..........................................................................................................19
Table 6 Key Identification.........................................................................................................................................22
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1. Security Target Introduction
This section identifies the Security Target (ST) and Target of Evaluation (TOE) identification, ST conventions, ST
conformance claims, and the ST organization. The TOE is Curtiss-Wright Defense Solutions Compact Network
Storage 4-Slot Software Encryption Layer provided by Curtiss-Wright Defense Solutions. The TOE is being
evaluated as a full drive encryption solution.
The Security Target contains the following additional sections:
 Conformance Claims (Section 2)
 Security Objectives (Section 3)
 Extended Components Definition (Section 4)
 Security Requirements (Section 5)
 TOE Summary Specification (Section 6)
Conventions
The following conventions have been applied in this document:
 Security Functional Requirements – Part 2 of the CC defines the approved set of operations that may be
applied to functional requirements: iteration, assignment, selection, and refinement.
o Iteration: allows a component to be used more than once with varying operations. In the ST,
iteration is indicated by a parenthetical number placed at the end of the component. For example
FDP_ACC.1(1) and FDP_ACC.1(2) indicate that the ST includes two iterations of the
FDP_ACC.1 requirement.
o Assignment: allows the specification of an identified parameter. Assignments are indicated using
bold and are surrounded by brackets (e.g., [assignment]). Note that an assignment within a
selection would be identified in italics and with embedded bold brackets (e.g., [[selected-
assignment]]).
o Selection: allows the specification of one or more elements from a list. Selections are indicated
using bold italics and are surrounded by brackets (e.g., [selection]).
o Refinement: allows the addition of details. Refinements are indicated using bold, for additions,
and strike-through, for deletions (e.g., “… all objects …” or “… some big things …”).
 Other sections of the ST – Other sections of the ST use bolding to highlight text of special interest, such as
captions.
1.1 Security Target Reference
ST Title – Curtiss-Wright Defense Solutions Compact Network Storage 4-Slot Software Encryption Layer
(FDEEEcPP20E/FDEAAcPP20E) Security Target
ST Version – Version 0.5
ST Date – 04/15/2019
1.2 TOE Reference
TOE Identification – Curtiss-Wright Defense Solutions Curtiss-Wright Defense Solutions Compact Network
Storage 4-Slot Software Encryption Layer
TOE Developer – Curtiss-Wright Defense Solutions
Evaluation Sponsor – Curtiss-Wright Defense Solutions
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1.3 TOE Overview
The Target of Evaluation (TOE) is Curtiss-Wright Defense Solutions Compact Network Storage 4-Slot Software
Encryption Layer.
The TOE provides software Full Drive Encryption of removable drives.
1.4 TOE Description
The CNS4 Software Encryption Layer (hereafter referred to as the TOE) is a rugged Network Attached Storage
(NAS) file server for use in Unmanned Aerial Vehicles (UAV), Unmanned Underwater Vehicles (UUV), and
Intelligence Surveillance Reconnaissance (ISR) aircraft. Easily integrated into network centric systems, the CNS4 is
an easy to use, turnkey, rugged network File Server that houses four Flash Storage Modules (FSMs) that provides
quick off load of data. The FSMs can be easily removed from one CNS4 and installed into any other CNS4
providing full, seamless data transfer between one or more networks in separate locations (e.g. ground => vehicle =>
ground). In addition to the software-based FDE layer provided by the CNS4, the CNS4 provides a hardware-based
Full Drive Encryption (FDE) layer to encrypt the drives within the FSMs. The hardware-based FDE layer is
addressed in a separate evaluation.
The Curtiss-Wright product supports networking protocols including SSH, CIFS, NFS, FTP, HTTP, DHCP, SNMP,
and iSCSI in addition to its RS-232 console port. The FDEEEcPP20E and FDEAAcPP20E Protection Profiles did
not consider, nor did they include networking protocols as part of the security functional requirements, and as a
result, did not include any requirements for addressing those protocols. Therefore, as per the FDEEEcPP20E and
FDEAAcPP20E, the protocols have not been examined as part of the required assurance activities and consequently
the evaluation can make no claims about the TOE’s networking protocols.
It is suggested that a customer using the product consider the impact of utilizing remote administration via SSH
across the network (rather than through the console) based upon their specific use case. The customer should factor
into their risk management decision the environment in which TOE operates (dedicated, segregated, private network
versus residing in a DMZ accessible to the Internet), and the value of data to be protected.
1.4.1 TOE Architecture
The TOE provides a software Full Drive Encryption solution that can accept Flash Storage Modules (FSMs) which
contain data drives within. The software encryption is based on Linux Unified Key Setup (LUKS). The LUKS-
based encryption is layered on the hardware encryption that was evaluated in a separate evaluation. This evaluation
addresses the encryption of data in software-based partitions while the hardware evaluation focused on the raw disk.
1.4.1.1 Physical Boundaries
The TOE’s physical boundary is the physical perimeter of its enclosure. The TOE provides a ruggedized solution to
secure Data at Rest (DAR).
1.4.1.2 Logical Boundaries
This section summarizes the security functions provided by CNS4 (SW Layer):
- Cryptographic support
- User data protection
- Security management
- Protection of the TSF
1.4.1.2.1 Cryptographic support
The TOE includes cryptographic functionality for key management, user authentication, and block-based encryption
including: symmetric key generation, encryption/decryption, cryptographic hashing, keyed-hash message
authentication, and password-based key derivation. These functions are supported with suitable random bit
generation, key derivation, salt generation, initialization vector generation, secure key storage, and key destruction.
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These primitive cryptographic functions are used to encrypt Data-At-Rest (including the generation and protection
of keys and key encryption keys) used by the TOE.
1.4.1.2.2 User data protection
The TOE performs Full Drive Encryption on all partitions on the drive (so that no plaintext exists) and does so
without user intervention.
1.4.1.2.3 Security management
The TOE provides each of required management services to manage the full drive encryption using a command line
interface.
1.4.1.2.4 Protection of the TSF
The TOE implements a number of features to protect itself to ensure the reliability and integrity of its security
features. It protects key and key material, and includes functions to perform self-tests and software/firmware
integrity checking so that it might detect when it is failing or may be corrupt. If any of the self-tests fail, the TOE
will not go into an operational mode.
1.4.2 TOE Documentation
CNS4 CSfC Common Airborne Recorder CSfC Encrypted Data Storage User Guide Part Number: DDOC0108-000-
A2 [Admin Guide]
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2. Conformance Claims
This TOE is conformant to the following CC specifications:
 Common Criteria for Information Technology Security Evaluation, Part 2: Security Functional
Components, CCMB-2017-04-002, Version 3.1 Revision 5, April 2017.
 Part 2 Extended
 Common Criteria for Information Technology Security Evaluation, Part 3: Security Assurance
Components, CCMB-2017-04-003, Version 3.1 Revision 5, April 2017.
 Part 3 Conformant
 Package Claims:
 collaborative Protection Profile for Full Drive Encryption - Encryption Engine, Version 2.0 +
Errata 20190201, February 1, 2019 and collaborative Protection Profile for Full Drive Encryption
Authorization Acquisition, Version 2.0 + Errata 20190201, February 1, 2019
(FDEEEcPP20E/FDEAAcPP20E)
 Technical Decisions:
 Applicable NIAP Technical decisions: None
2.1 Conformance Rationale
The ST conforms to the FDEEEcPP20E/FDEAAcPP20E. As explained previously, the security problem definition,
security objectives, and security requirements have been drawn from the PP.
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3. Security Objectives
The Security Problem Definition may be found in the FDEEEcPP20E/FDEAAcPP20E and this section reproduces
only the corresponding Security Objectives for the operational environment for reader convenience. The
FDEEEcPP20E/FDEAAcPP20E offers additional information about the identified security objectives, but that has
not been reproduced here and the FDEEEcPP20E/FDEAAcPP20E should be consulted if there is interest in that
material.
In general, the FDEEEcPP20E/FDEAAcPP20E has defined Security Objectives appropriate for Full Drive
Encryption and as such are applicable to the Curtiss-Wright Defense Solutions Compact Network Storage 4-Slot
Software Encryption Layer TOE.
3.1 Security Objectives for the Operational Environment
OE.INITIAL_DRIVE_STATE The OE provides a newly provisioned or initialized storage device free of
protected data in areas not targeted for encryption.
OE.PASSPHRASE_STRENGTH An authorized administrator will be responsible for ensuring that the
passphrase authorization factor conforms to guidance from the Enterprise using the TOE.
OE.PHYSICAL The Operational Environment will provide a secure physical computing space such than
an adversary is not able to make modifications to the environment or to the TOE itself.
OE.PLATFORM_I&A The Operational Environment will provide individual user identification and
authentication mechanisms that operate independently of the authorization factors used by the TOE.
OE.PLATFORM_STATE The platform in which the storage device resides (or an external storage device
is connected) is free of malware that could interfere with the correct operation of the product.
OE.POWER_DOWN Volatile memory is cleared after power-off so memory remnant attacks are
infeasible.
OE.SINGLE_USE_ET External tokens that contain authorization factors will be used for no other purpose
than to store the external token authorization factor.
OE.STRONG_ENVIRONMENT_CRYPTO The Operating Environment will provide a cryptographic
function capability that is commensurate with the requirements and capabilities of the TOE and Appendix
A.
OE.TRAINED_USERS Authorized users will be properly trained and follow all guidance for securing the
TOE and authorization factors.
OE.TRUSTED_CHANNEL Communication among and between product components (i.e., AA and EE) is
sufficiently protected to prevent information disclosure.
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4. Extended Components Definition
All of the extended requirements in this ST have been drawn from the FDEEEcPP20E/FDEAAcPP20E. The
FDEEEcPP20E/FDEAAcPP20E defines the following extended requirements and since they are not redefined in
this ST the FDEEEcPP20E/FDEAAcPP20E should be consulted for more information in regard to those CC
extensions.
Extended SFRs:
- FCS_AFA_EXT.1: Authorization Factor Acquisition
- FCS_AFA_EXT.2: Timing of Authorization Factor Acquisition
- FCS_CKM_EXT.4(a): Cryptographic Key and Key Material Destruction (Destruction Timing)
- FCS_CKM_EXT.4(b): Cryptographic Key and Key Material Destruction (Power Management)
- FCS_CKM_EXT.6: Cryptographic Key Destruction Types
- FCS_KDF_EXT.1: Cryptographic Key Derivation
- FCS_KYC_EXT.1: Key Chaining (Initiator)
- FCS_KYC_EXT.2: Key Chaining (Recipient)
- FCS_PCC_EXT.1: Cryptographic Password Construct and Conditioning
- FCS_RBG_EXT.1: Extended: Cryptographic Operation (Random Bit Generation)
- FCS_SNI_EXT.1: Cryptographic Operation (Salt, Nonce, and Initialization Vector Generation)
- FCS_VAL_EXT.1: Validation
- FDP_DSK_EXT.1: Protection of Data on Disk
- FPT_KYP_EXT.1: Protection of Key and Key Material
- FPT_PWR_EXT.1: Power Saving States
- FPT_PWR_EXT.2: Timing of Power Saving States
- FPT_TST_EXT.1: TSF Testing
- FPT_TUD_EXT.1: Trusted Update
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5. Security Requirements
This section defines the Security Functional Requirements (SFRs) and Security Assurance Requirements (SARs)
that serve to represent the security functional claims for the Target of Evaluation (TOE) and to scope the evaluation
effort.
The SFRs have all been drawn from the FDEEEcPP20E/FDEAAcPP20E. The refinements and operations already
performed in the FDEEEcPP20E/FDEAAcPP20E are not identified (e.g., highlighted) here, rather the requirements
have been copied from the FDEEEcPP20E/FDEAAcPP20E and any residual operations have been completed
herein. Of particular note, the FDEEEcPP20E/FDEAAcPP20E made a number of refinements and completed some
of the SFR operations defined in the Common Criteria (CC) and that PP should be consulted to identify those
changes if necessary.
The SARs are also drawn from the FDEEEcPP20E/FDEAAcPP20E which includes all the SARs for EAL 1.
However, the SARs are effectively refined since requirement-specific 'Assurance Activities' are defined in the
FDEEEcPP20E/FDEAAcPP20E that serve to ensure corresponding evaluations will yield more practical and
consistent assurance than the EAL 1 assurance requirements alone. The FDEEEcPP20E/FDEAAcPP20E should be
consulted for the assurance activity definitions.
5.1 TOE Security Functional Requirements
The following table identifies the SFRs that are satisfied by Curtiss-Wright Defense Solutions Compact Network
Storage 4-Slot Software Encryption Layer TOE.
Requirement Class Requirement Component
FCS: Cryptographic
support
FCS_AFA_EXT.1: Authorization Factor Acquisition
FCS_AFA_EXT.2: Timing of Authorization Factor Acquisition
FCS_CKM.1(c): Cryptographic Key Generation (Data Encryption Key)
FCS_CKM.4(a): Cryptographic Key Destruction (Power Management)
FCS_CKM.4(d): Cryptographic Key Destruction (Software TOE, 3rd Party
Storage)
FCS_CKM_EXT.4(a): Cryptographic Key and Key Material Destruction
(Destruction Timing)
FCS_CKM_EXT.4(b): Cryptographic Key and Key Material Destruction (Power
Management)
FCS_CKM_EXT.6: Cryptographic Key Destruction Types
FCS_COP.1(a): Cryptographic Operation (Signature Verification)
FCS_COP.1(b): Cryptographic operation (Hash Algorithm)
FCS_COP.1(c): Cryptographic operation (Keyed Hash Algorithm)
FCS_COP.1(d): Cryptographic operation (Key Wrapping)
FCS_COP.1(f): Cryptographic operation (AES Data Encryption/Decryption)
FCS_COP.1(g): Cryptographic operation (Key Encryption)
FCS_KDF_EXT.1: Cryptographic Key Derivation
FCS_KYC_EXT.1: Key Chaining (Initiator)
FCS_KYC_EXT.2: Key Chaining (Recipient)
FCS_PCC_EXT.1: Cryptographic Password Construct and Conditioning
FCS_RBG_EXT.1: Extended: Cryptographic Operation (Random Bit Generation)
FCS_SNI_EXT.1: Cryptographic Operation (Salt, Nonce, and Initialization Vector
Generation)
FCS_VAL_EXT.1: Validation
FDP: User data
protection
FDP_DSK_EXT.1: Protection of Data on Disk
FMT: Security FMT_MOF.1: Management of Functions Behavior
management FMT_SMF.1: Specification of Management Functions
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FMT_SMR.1: Security Roles
FPT: Protection FPT_KYP_EXT.1: Protection of Key and Key Material
of the TSF FPT_PWR_EXT.1: Power Saving States
FPT_PWR_EXT.2: Timing of Power Saving States
FPT_TST_EXT.1: TSF Testing
FPT_TUD_EXT.1: Trusted Update
Table 1 TOE Security Functional Components
5.1.1 Cryptographic support (FCS)
5.1.1.1 Authorization Factor Acquisition (FCS_AFA_EXT.1)
FCS_AFA_EXT.1.1
The TSF shall accept the following authorization factors: [- a submask derived from a password
authorization factor conditioned as defined in FCS_PCC_EXT.1].
5.1.1.2 Timing of Authorization Factor Acquisition (FCS_AFA_EXT.2)
FCS_AFA_EXT.2.1
The TSF shall reacquire the authorization factor(s) specified in FCS_AFA_EXT.1 upon transition
from any Compliant power saving state specified in FPT_PWR_EXT.1 prior to permitting access
to plaintext data.
5.1.1.3 Cryptographic Key Generation (Data Encryption Key) (FCS_CKM.1(c))
FCS_CKM.1(c).1
Refinement: The TSF shall generate cryptographic keys in accordance with a specified
cryptographic key generation method [- generate a DEK using the RBG as specified in
FCS_RBG_EXT.1] and specified cryptographic key sizes [256 bits].
5.1.1.4 Cryptographic Key Destruction (Power Management) (FCS_CKM.4(a)) 1
FCS_CKM.4(a).1
Refinement: The TSF shall [erase] cryptographic keys and key material from volatile memory
when transitioning to a Compliant power saving state as defined by FPT_PWR_EXT.1 that meets
the following: a key destruction method specified in FCS_CKM_EXT.6.
5.1.1.5 Cryptographic Key Destruction (Software TOE, 3rd Party Storage) (FCS_CKM.4(d))
FCS_CKM.4(d).1
Refinement: The TSF shall destroy cryptographic keys in accordance with a specified
cryptographic key destruction method [
- For volatile memory, the destruction shall be executed by a [
- single overwrite consisting of [zeros]
- removal of power to the memory],
- For non-volatile storage that consists of the invocation of an interface provided by the
underlying platform that [o logically addresses the storage location of the key and performs a
[single] overwrite consisting of [zeros]]] that meets the following: no standard.
1
The FDEEEcPP20E version is used as it addresses the FDEAAcPP20E requirement by requiring key destruction as
specified in FCS_CKM.4(d). In this ST, the FCS_CKM_EXT.6 requirement points to FCS_CKM.4(d).
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5.1.1.6 Cryptographic Key and Key Material Destruction (Destruction Timing) (FCS_CKM_EXT.4(a))
FCS_CKM_EXT.4(a).1
The TSF shall destroy all keys and key material when no longer needed.
5.1.1.7 Cryptographic Key and Key Material Destruction (Power Management) (FCS_CKM_EXT.4(b))
FCS_CKM_EXT.4(b).1
Refinement: The TSF shall destroy all key material, BEV, and authentication factors stored in
plaintext when transitioning to a Compliant power saving state as defined by FPT_PWR_EXT.1.
5.1.1.8 Cryptographic Key Destruction Types (FCS_CKM_EXT.6)
FCS_CKM_EXT.6.1
The TSF shall use [FCS_CKM.4(d)] key destruction methods.
5.1.1.9 Cryptographic Operation (Signature Verification) (FCS_COP.1(a))
FCS_COP.1(a).1
Refinement: The TSF shall perform cryptographic signature services (verification) in accordance
with a [Elliptic Curve Digital Signature Algorithm with a key size of 256 bits or greater] that
meet the following:[FIPS PUB 186-4, 'Digital Signature Standard (DSS)', Section 6 and
Appendix D, Implementing 'NIST curves' [P-521]; ISO/IEC 14888-3, Section 6.4, for ECDSA
schemes].
5.1.1.10 Cryptographic operation (Hash Algorithm) (FCS_COP.1(b))
FCS_COP.1(b).1
Refinement: The TSF shall perform cryptographic hashing services in accordance with a specified
cryptographic algorithm [SHA-256, SHA-512] that meet the following: ISO/IEC 10118-3:2004.
5.1.1.11 Cryptographic operation (Keyed Hash Algorithm) (FCS_COP.1(c))
FCS_COP.1(c).1
Refinement: The TSF shall perform cryptographic keyed-hash message authentication in
accordance with a specified cryptographic algorithm [HMAC-SHA-256] and cryptographic key
sizes [256] that meet the following: ISO/IEC 9797-2:2011, Section 7 'MAC Algorithm 2'.
5.1.1.12 Cryptographic operation (AES Data Encryption/Decryption) (FCS_COP.1(f))
FCS_COP.1(f).1
The TSF shall perform data encryption and decryption in accordance with a specified
cryptographic algorithm AES used in [CBC] mode and cryptographic key sizes [256 bits] that
meet the following: AES as specified in ISO /IEC 18033-3, [CBC as specified in ISO/IEC
10116].
5.1.1.13 Cryptographic operation (Key Encryption) (FCS_COP.1(g))
FCS_COP.1(g).1
Refinement: The TSF shall perform key encryption and decryption in accordance with a specified
cryptographic algorithm AES used in [CBC] mode and cryptographic key sizes [256 bits] that
meet the following: AES as specified in ISO /IEC 18033-3, [CBC as specified in ISO/IEC
10116].
5.1.1.14 Cryptographic Key Derivation (FCS_KDF_EXT.1)
FCS_KDF_EXT.1.1
The TSF shall accept [a conditioned password submask] to derive an intermediate key, as defined
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in [NIST SP 800-132] , using the keyed-hash functions specified in FCS_COP.1(c), such that the
output is at least of equivalent security strength (in number of bits) to the BEV.
5.1.1.15 Key Chaining (Initiator) (FCS_KYC_EXT.1)
FCS_KYC_EXT.1.1
The TSF shall maintain a key chain of: intermediate keys originating from one or more
submask(s) to the BEV using the following method(s): [key derivation as specified in
FCS_KDF_EXT.1] while maintaining an effective strength of [256 bits] for symmetric keys and
an effective strength of [not applicable] for asymmetric keys.
FCS_KYC_EXT.1.2
The TSF shall provide at least a [256 bit] BEV to [the encryption engine] [- without validation
taking place].
5.1.1.16 Key Chaining (Recipient) (FCS_KYC_EXT.2)
FCS_KYC_EXT.2.1
The TSF shall accept a BEV of at least [256 bits] from the AA.
FCS_KYC_EXT.2.2
The TSF shall maintain a chain of intermediary keys originating from the BEV to the DEK using
the following method(s): [- key encryption as specified in FCS_COP.1(g)] while maintaining an
effective strength of [256 bits] for symmetric keys and an effective strength of [not applicable] for
asymmetric keys.
5.1.1.17 Cryptographic Password Construct and Conditioning (FCS_PCC_EXT.1)
FCS_PCC_EXT.1.1
A password used by the TSF to generate a password authorization factor shall enable up to [512]
characters in the set of upper case characters, lower case characters, numbers, and [all ASCII
printable characters] and shall perform Password-based Key Derivation Functions in accordance
with a specified cryptographic algorithm HMAC-[SHA-256], with [89,0001] iterations, and output
cryptographic key sizes [256 bits] that meet the following: NIST SP 800-132.
5.1.1.18 Extended: Cryptographic Operation (Random Bit Generation) (FCS_RBG_EXT.1)
FCS_RBG_EXT.1.1
The TSF shall perform all deterministic random bit generation services in accordance with
[ISO/IEC 18031:2011] using [HMAC_DRBG (any)]].
FCS_RBG_EXT.1.2
The deterministic RBG shall be seeded by at least one entropy source that accumulates entropy
from [[one] hardware-based noise source(s)] with a minimum of [256 bits] of entropy at least
equal to the greatest security strength, according to ISO/IEC 18031:2011 Table C.1 'Security
Strength Table for Hash Functions', of the keys and hashes that it will generate.
5.1.1.19 Cryptographic Operation (Salt, Nonce, and Initialization Vector Generation) (FCS_SNI_EXT.1)
FCS_SNI_EXT.1.1
The TSF shall [use salts that are generated by a [DRBG as specified in FCS_RBG_EXT.1]].
FCS_SNI_EXT.1.2
The TSF shall use [no nonces].
FCS_SNI_EXT.1.3
The TSF shall create IVs in the following manner [- CBC: IVs shall be non-repeating and
unpredictable].
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5.1.1.20 Validation (FCS_VAL_EXT.1) 2
FCS_VAL_EXT.1.1
The TSF shall perform validation of the BEV using the following method(s): [- hash the BEV as
specified in [FCS_COP.1(c)] and compare it to a stored hashed value].
FCS_VAL_EXT.1.2
The TSF shall require the validation of the BEV prior to allowing access to TSF data after exiting
a Compliant power saving state.
FCS_VAL_EXT.1.3
The TSF shall [- block validation after [three attempts] of consecutive failed validation attempts
- require power cycle/reset the TOE after [three attempts] of consecutive failed validation
attempts].
5.1.2 User data protection (FDP)
5.1.2.1 Protection of Data on Disk (FDP_DSK_EXT.1)
FDP_DSK_EXT.1.1
The TSF shall perform Full Drive Encryption in accordance with FCS_COP.1(f), such that the
drive contains no plaintext protected data.
FDP_DSK_EXT.1.2
The TSF shall encrypt all protected data without user intervention.
5.1.3 Security management (FMT)
5.1.3.1 Management of Functions Behavior (FMT_MOF.1)
FMT_MOF.1.1
The TSF shall restrict the ability to modify the behaviour of the functions use of Compliant power
saving state to authorized users.
5.1.3.2 Specification of Management Functions (FMT_SMF.1)
FMT_SMF.1.1
The TSF shall be capable of performing the following management functions: [
a) forwarding requests to change the DEK to the EE,
b) forwarding requests to cryptographically erase the DEK to the EE,
c) allowing authorized users to change authorization factors or set of authorization factors used,
d) change the DEK, as specified in FCS_CKM.1, when reprovisioning or when commanded,
e) erase the DEK, as specified in FCS_CKM.4(a), [selection:
f) initiate TOE firmware/software updates,
g) [no other functions]
5.1.3.3 Security Roles (FMT_SMR.1)
FMT_SMR.1.1
The TSF shall maintain the roles authorized users.
FMT_SMR.1.2
The TSF shall be able to associate users with roles.
2
The FDEEEcPP20E version is used as it addresses the FDEAAcPP20E requirement by including the BEV in the
first element and requiring validation of the BEV in the second element.
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5.1.4 Protection of the TSF (FPT)
5.1.4.1 Protection of Key and Key Material (FPT_KYP_EXT.1)
FPT_KYP_EXT.1.1
The TSF shall [only store keys in non-volatile memory when wrapped, as specified in
FCS_COP.1(d), or encrypted, as specified in FCS_COP.1(g) or FCS_COP.1(e)].
5.1.4.2 Power Saving States (FPT_PWR_EXT.1)
FPT_PWR_EXT.1.1
The TSF shall define the following Compliant power saving states: [G3].
5.1.4.3 Timing of Power Saving States (FPT_PWR_EXT.2)
FPT_PWR_EXT.2.1
For each Compliant power saving state defined in FPT_PWR_EXT.1.1, the TSF shall enter the
Compliant power saving state when the following conditions occur:
user-initiated request,
[shutdown,
request initiated by remote management system].
5.1.4.4 TSF Testing (FPT_TST_EXT.1)
FPT_TST_EXT.1.1
The TSF shall run a suite of the following self-tests [during initial start-up (on power on)] to
demonstrate the correct operation of the TSF: [Cryptographic Algorithm Self-tests].
5.1.4.5 Trusted Update (FPT_TUD_EXT.1)
FPT_TUD_EXT.1.1
Refinement: The TSF shall provide authorized users the ability to query the current version of the
TOE [software].
FPT_TUD_EXT.1.2
Refinement: The TSF shall provide authorized users the ability to initiate updates to TOE
[software].
FPT_TUD_EXT.1.3
Refinement: The TSF shall verify updates to the TOE [software] using a [digital signature as
specified in FCS_COP.1(a)] by the manufacturer prior to installing those updates.
5.2 TOE Security Assurance Requirements
The SARs for the TOE are the components as specified in Part 3 of the Common Criteria. Note that the SARs have
effectively been refined with the assurance activities explicitly defined in association with both the SFRs and SARs.
Requirement Class Requirement Component
ADV: Development ADV_FSP.1: Basic functional specification
AGD: Guidance documents AGD_OPE.1: Operational user guidance
AGD_PRE.1: Preparative procedures
ALC: Life-cycle support ALC_CMC.1: Labelling of the TOE
ALC_CMS.1: TOE CM coverage
ATE: Tests ATE_IND.1: Independent testing - conformance
AVA: Vulnerability assessment AVA_VAN.1: Vulnerability survey
Table 2 Assurance Components
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5.2.1 Development (ADV)
5.2.1.1 Basic functional specification (ADV_FSP.1)
ADV_FSP.1.1d
The developer shall provide a functional specification.
ADV_FSP.1.2d
The developer shall provide a tracing from the functional specification to the SFRs.
ADV_FSP.1.1c
The functional specification shall describe the purpose and method of use for each SFR-enforcing
and SFR-supporting TSFI.
ADV_FSP.1.2c
The functional specification shall identify all parameters associated with each SFR-enforcing and
SFR-supporting TSFI.
ADV_FSP.1.3c
The functional specification shall provide rationale for the implicit categorisation of interfaces as
SFR-non-interfering.
ADV_FSP.1.4c
The tracing shall demonstrate that the SFRs trace to TSFIs in the functional specification.
ADV_FSP.1.1e
The evaluator shall confirm that the information provided meets all requirements for content and
presentation of evidence.
ADV_FSP.1.2e
The evaluator shall determine that the functional specification is an accurate and complete
instantiation of the SFRs.
5.2.2 Guidance documents (AGD)
5.2.2.1 Operational user guidance (AGD_OPE.1)
AGD_OPE.1.1d
The developer shall provide operational user guidance.
AGD_OPE.1.1c
The operational user guidance shall describe, for each user role, the user-accessible functions and
privileges that should be controlled in a secure processing environment, including appropriate
warnings.
AGD_OPE.1.2c
The operational user guidance shall describe, for each user role, how to use the available interfaces
provided by the TOE in a secure manner.
AGD_OPE.1.3c
The operational user guidance shall describe, for each user role, the available functions and
interfaces, in particular all security parameters under the control of the user, indicating secure
values as appropriate.
AGD_OPE.1.4c
The operational user guidance shall, for each user role, clearly present each type of security-
relevant event relative to the user-accessible functions that need to be performed, including
changing the security characteristics of entities under the control of the TSF.
AGD_OPE.1.5c
The operational user guidance shall identify all possible modes of operation of the TOE (including
operation following failure or operational error), their consequences and implications for
maintaining secure operation.
AGD_OPE.1.6c
The operational user guidance shall, for each user role, describe the security measures to be
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followed in order to fulfil the security objectives for the operational environment as described in
the ST.
AGD_OPE.1.7c
The operational user guidance shall be clear and reasonable.
AGD_OPE.1.1e
The evaluator shall confirm that the information provided meets all requirements for content and
presentation of evidence.
5.2.2.2 Preparative procedures (AGD_PRE.1)
AGD_PRE.1.1d
The developer shall provide the TOE including its preparative procedures.
AGD_PRE.1.1c
The preparative procedures shall describe all the steps necessary for secure acceptance of the
delivered TOE in accordance with the developer's delivery procedures.
AGD_PRE.1.2c
The preparative procedures shall describe all the steps necessary for secure installation of the TOE
and for the secure preparation of the operational environment in accordance with the security
objectives for the operational environment as described in the ST.
AGD_PRE.1.1e
The evaluator shall confirm that the information provided meets all requirements for content and
presentation of evidence.
AGD_PRE.1.2e
The evaluator shall apply the preparative procedures to confirm that the TOE can be prepared
securely for operation.
5.2.3 Life-cycle support (ALC)
5.2.3.1 Labelling of the TOE (ALC_CMC.1)
ALC_CMC.1.1d
The developer shall provide the TOE and a reference for the TOE.
ALC_CMC.1.1c
The TOE shall be labelled with its unique reference.
ALC_CMC.1.1e
The evaluator shall confirm that the information provided meets all requirements for content and
presentation of evidence.
5.2.3.2 TOE CM coverage (ALC_CMS.1)
ALC_CMS.1.1d
The developer shall provide a configuration list for the TOE.
ALC_CMS.1.1c
The configuration list shall include the following: the TOE itself; and the evaluation evidence
required by the SARs.
ALC_CMS.1.2c
The configuration list shall uniquely identify the configuration items.
ALC_CMS.1.1e
The evaluator shall confirm that the information provided meets all requirements for content and
presentation of evidence.
5.2.4 Security Target (ASE)
5.2.4.1 Security Target (ASE_TSS.1)
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ASE_TSS.1.1c
Refinement: The TOE summary specification shall describe how the TOE meets each SFR,
including a proprietary Key Management Description (Appendix E), and [Entropy Essay].
5.2.5 Tests (ATE)
5.2.5.1 Independent testing - conformance (ATE_IND.1)
ATE_IND.1.1d
The developer shall provide the TOE for testing.
ATE_IND.1.1c
The TOE shall be suitable for testing.
ATE_IND.1.1e
The evaluator shall confirm that the information provided meets all requirements for content and
presentation of evidence.
ATE_IND.1.2e
The evaluator shall test a subset of the TSF to confirm that the TSF operates as specified.
5.2.6 Vulnerability assessment (AVA)
5.2.6.1 Vulnerability survey (AVA_VAN.1)
AVA_VAN.1.1d
The developer shall provide the TOE for testing.
AVA_VAN.1.1c
The TOE shall be suitable for testing.
AVA_VAN.1.1e
The evaluator shall confirm that the information provided meets all requirements for content and
presentation of evidence.
AVA_VAN.1.2e
The evaluator shall perform a search of public domain sources to identify potential vulnerabilities
in the TOE.
AVA_VAN.1.3e
The evaluator shall conduct penetration testing, based on the identified potential vulnerabilities, to
determine that the TOE is resistant to attacks performed by an attacker possessing Basic attack
potential.
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6. TOE Summary Specification
This chapter describes the security functions:
- Cryptographic support
- User data protection
- Security management
- Protection of the TSF
6.1 Cryptographic support
The Cryptographic support function satisfies the following security functional requirements:
 FCS_AFA_EXT.1: The TOE supports password authorization factor, and the password may be between 8
and (up to) 512 characters in length and can be composed of all ASCII printable characters.
 FCS_AFA_EXT.2: The TOE does not have any power-saving states beyond power-on and power-off. After
transitioning from the power-off to the power-on state, the administrator must authenticate and make the
encrypted partition available before the TOE will allow data to be read from or written to the drive.
 FCS_CKM.1(c): The TOE generates 256-bit DEKs using its SHA-256 HMAC_DRBG. Because the DRBG
has a security strength of 256 bits, the DEKs generated are sufficient for the TOE’s 256-bit AES data
encryption/decryption. The TOE stores these keys encrypted in dedicated headers on the drives (in the first
few megabytes of an unpartitioned, drives or at the start of each partition).
 FCS_CKM.4(a): When the TOE powers off (as the TOE has no other power states other than on and off
(G3)), all values in memory drain to a zero state.
 FCS_CKM.4(d): The TOE has 4GB of RAM, and this serves as the working memory in which the TOE
temporarily stores working copies of key material (for example, the Derived Key [DerKey], which is
derived from the user's password and salt using PBKDFv2 and the DEKs currently in use (if any). The TOE
clears keys from memory by a removal of power. The TOE also clears keys when they are no longer in use
by overwriting them with zeroes.
Additionally, the TOE stores encrypted DEKs in a header for the encrypted drive partitions. The TOE
clears these keys by through an internal call using the CRYPT_WIPE_RANDOM pattern, which draws
random data from the TOE's HMAC_DRBG.
 FCS_CKM_EXT.4(a): The TOE clears the DerKey and DEKs from userspace memory immediately after
the operation for which it is needed, while DEKs will be held in kernel memory while the drive is
accessible. If the user logs out, then the TOE will clear any in-use DEKs from kernel memory. Keys are
also cleared upon removal of power.
 FCS_CKM_EXT.4(b): The TOE has no Compliant power saving states other than power on and off (G3).
 FCS_CKM_EXT.6: The TOE clears its keys in accordance with FCS_CKM.4(d).
 FCS_COP.1: The TOE performs cryptographic algorithms in accordance with the following NIST
standards and has received the following CAVP algorithm certificates.
The TOE uses its OpenSSL library when verifying ECDSA P-521 w/ SHA-512 trusted update signatures.
SFR Algorithm NIST Standard Cert#
FCS_COP.1(a) (Verify) ECDSA P-521 w/ SHA-512 Verify FIPS 186-4, ECDSA 1500
FCS_COP.1(b) (Hash) SHA-512 Hashing FIPS 180-4 4471
Table 3 OpenSSL Cryptographic Algorithms
The TOE uses its kernel cryptography when doing AES-256 CBC ESSIV:SHA-256 data encryption/decryption.
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SFR Algorithm NIST Standard Cert#
FCS_COP.1(b) (Hash) SHA-256 Hashing FIPS 180-4 4470
FCS_COP.1(f) (AES) AES-256 CBC Encrypt/Decrypt FIPS 197 5564
Table 4 kernel Cryptographic Algorithms
The TOE uses its libgcrypt library when doing key derivation and key management operations.
SFR Algorithm NIST Standard Cert#
FCS_COP.1(b) (Hash) SHA-256 Hashing FIPS 180-4 4472
FCS_COP.1(d) (Keyed Hash) HMAC-SHA-256 FIPS 198-1 & 180-4 3709
FCS_COP.1(f) (AES) AES-256 CBC Encrypt/Decrypt FIPS 197 5565
FCS_RBG_EXT.1 (Random) SHA-256 HMAC_DRBG SP 800-90A 2218
Table 5 libgcrypt Cryptographic Algorithms
 FCS_COP.1(a): The TOE utilizes ECDSA P-521 w/ SHA-512 signatures to verify the authenticity of
firmware updates. Upon receiving a candidate update and the accompanying signature file, the TOE uses
an embedded public key (see FPT_TUD_EXT.1 below for the location) to verify the ECDSA signature
against the received image. The verification uses SHA-512 and follows the FIPS 186-4 ECDSA format.
 FCS_COP.1(b): The TOE's kernel, libgcrypt, and OpenSSL libraries provide the SHA-256 and SHA-512
algorithms and use those algorithms as part of ESSIV:SHA-256 IV generation, PBKDFv2 password-based
key derivation, and trusted update signature verification respectively.
 FCS_COP.1(c): The TOE implements HMAC-SHA-256 using 256-bit keys, the SHA-256 hash algorithm,
a 512-bit block size, and an output MAC length of 256 bits.
 FCS_COP.1(f): The TOE uses an AES CBC kernel implementation dedicated to drive
encryption/decryption. This implementation uses AES- 256 bit keys.
 FCS_COP.1(g): The TOE has a libgcrypt AES CBC implementation used for key managements operations
(decryption of the encrypted DEKs). This implementation uses AES- 256 bit keys.
 FCS_KDF_EXT.1: The TOE uses 800-132 (PBKDFv2) with HMAC-SHA-256 and a number of iterations
and a 256 bit salt to transform the operator's password into a Derived Key for decrypting the encrypted
DEKs. The number of iterations is determined by the specified number of milliseconds (2000 milliseconds)
multiplied by the number of PBKDF operations per/second to achieve a delay specified by the
administrator. The TOE has an empirically determined benchmark for PBKDF2-sha256 of 44,521
iterations per second for a 256-bit key, and thus the TOE uses a count of ~89,000 iterations to achieve a 2
second delay.
 FCS_KYC_EXT.1/2: The TOE uses PBKDFv2 to transform the operator's password into a 256-bit BEV,
and then uses that BEV to AES decrypt the DEKs stored in the header(s) stored on the drive.
 FCS_PCC_EXT.1: The TOE allows passwords up to 512 characters in length, and the TOE allows
uppercase/lowercase letters, numbers, and ASCII printable characters. The TOE will reject a password
containing other characters. The TOE conditions passwords by combining them with a 256-bit salt using
PBKDFv2.
 FCS_RBG_EXT.1: The TOE includes an SHA-256 HMAC_DRBG that it seeds with at least 256-bits of
entropy from a hardware-based noise source.
 FCS_SNI_EXT.1: The TOE generates its salts using its SHA-256 HMAC_DRBG. The TOE generates its
AES-CBC IVs using ESSIV:SHA256. The TOE does not generate nonces nor tweaks (as the TOE doesn’t
support AES-XTS).
 FCS_VAL_EXT.1: The TOE validates the operator's password by first subjecting the password and salt to
PBKDFv2 to form the Derived Key (DerKey). The TOE uses the DerKey to decrypt the masterKey stripes
and reconstitutes the masterKey; however, before using the masterKey, the TOE first performs iterative
HMAC-SHA-256 using the operator's password, the masterKey salt, masterKey iterations, and masterKey
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as inputs, and then compares the resulting value to the stored masterKey's digest stored in the header to
ensure the two match.
If the TOE detects more than three incorrect passwords, then the TOE will block all subsequent attempts to
validate the operator’s password (and not even attempt to validate the password). The TOE clears its
counter upon a reboot.
6.2 User data protection
The User data protection function satisfies the following security functional requirements:
 FDP_DSK_EXT.1: The TOE provides FDE that encrypts the entirety of each drive partition through AES-
CBC block based encryption. The Admin Guide describes the TOE’s initialization process and setup for
the SW-layer. The TOE maintains a separate, unencrypted, internal Flash chip to house its CentOS-based
firmware that is beyond the FSM drive that the TOE encrypts. If the administrator configures the FSM
drive for use as a raw block device, then the TOE encrypts the entire drive (with a small area reserved for
the LUKS header). Otherwise, if the administrator chooses to partition the FSM drive, then the drive’s
partition table and LUKS headers for each partition will be in plaintext, with all partition data encrypted.
6.3 Security management
The Security management function satisfies the following security functional requirements:
 FMT_MOF.1: The TOE claims no Compliant power saving states beyond power on and off. Only the
authorized administrator can issue the shutdown command.
 FMT_SMF.1: The TOE provides each of the required management services with no additional ones.
Because the TOE fulfills the AA and EE requirements together, the TOE need not “forward” requests to
change the DEK or cryptographically erase the DEK. Instead, the TOE provides an administrator
command that will erase the DEK (“sysconfig --wipe --force”) and a command to create a new
partition (“sysconfig -s 0 --part 2 50% 50% --force”). The TOE supports changing of
the authorization factors (the administrator can remove a partition and recreate it to change the associated
password). The Admin Guide describes the TOE’s “Field Update” process, which consists of securely
copying the new update image and signature file to the TOE and then executing the “fupdate”
command, after which the TOE will detect the new update, verify the signature, and (if the signature
verifies successfully) install the update. The TOE does not provide any manageable power-saving states.
 FMT_SMR.1 – The TOE maintains an administer role that can administer the TOE.
6.4 Protection of the TSF
The Protection of the TSF function satisfies the following security functional requirements:
 FPT_KYP_EXT.1: The TOE stores encrypted DEKs in the header of each drive partition.
 FPT_PWR_EXT.1/2: The TOE provides the Compliant power-saving state G3, mechanical off. . The TOE
enters this state when the user shuts off the device, or when the remote administrator shuts down the
device. The TOE must be fully rebooted from this state.
 FPT_TST_EXT.1: The TOE includes the following power-up Known Answer Tests (KATs) to ensure that
each of its cryptographic algorithms operates correctly.
- OpenSSL - ECDSA sign/verify test
- OpenSSL – SHA-512 hashing test
- OpenSSL – integrity test
- kernel – SHA-256 hashing test
- kernel – AES-256 CBC encrypt/decrypt test
- kernel – integrity test
- libgcrypt – SHA hashing tests
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- libgcrypt – HMAC-SHA tests
- libgcrypt – AES-256 CBC encrypt/decrypt test
- libgcrypt – SHA-256 HMAC_DRBG test
- libgcrypt – integrity test
The TOE also has a set of functional self tests. The information from these tests is stored within the
temporary file system and can be viewed using the ‘log’ command.
- PBIT (Power-on Built In Test) – performs a basic check of critical components on the system
(tests the physical RAM and tests data communication paths.
- CBIT (Continuous Built In Test) - checks sensors, SATA status and errors
- IBIT (Instantiated Built In Test) - performs a more in-depth status check of components such as all
communication paths, individual I2C devices, the eNOVA hardware encryptors, voltages, and
S.M.A.R.T. data from the FSM-C’s.
 FPT_TUD_EXT.1: The TOE can display its current firmware version and has the ability to field update its
software using signed updates. The TOE will verify the signature on a firmware upgrade (using its
OpenSSL library in conjunction with the embedded /root/fupdate/cwdts_publickey.pem key to verify the
ECDSA P-521 with SHA-512 signature) before installing it, and will reject any update with an invalid
signature. The signature used for update validation is protected because it lives on the operating system that
is stored on Flash belonging to the dedicated, physically separate computing system.
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7. Key Management Description
The key management description explains each key, cryptomodule and overall encryption architecture. Each key is
identified in the table below.
Key Identifier Storage
Location
How Key
Protected
How key Derived Strength of
Key
When Key Destroyed
User Passphrase Memory -
transient
N/A N/A N/A Immediately after use
Derived Key Memory N/A The TOE uses 800-132
KDF in counter mode
using HMAC-SHA-256
and a number of
iterations and a 256 bit
salt to transform the
operator's password into
a Derived Key
256 bits Immediately after use
DEK Memory and
Partition
Header
AES CBC
Encrypted
Generated from
approved DRBG
256 bits When partition closed
or when partition no
longer encrypted
Table 6 Key Identification
The data encryption engine is based on LUKS, and is comprised of both a userspace component and a kernel-level
component. The userspace component handles derivation of the Derived Key from the user's password and the
subsequent decryption of the DEK with the Derived Key. The kernel-level component receives the DEK from the
userspace component and then encrypts/decrypts data written to/read from the encrypted partition/drive. The data
encryption engine itself is a Network Attached Storage (NAS) device, where all executable code of the data
encryption engine executes within a dedicated processor, with its own dedicated Flash memory. While the TOE
does not encrypt its internal dedicated Flash memory, it provides no access to this memory, and only exposes the
encrypted Flash Storage Module (drive) to network-attached clients. The TOE ensures that access to the
FSM/drives is always encrypted, and does not permit plaintext access to protected partitions or drives. Because the
TOE utilizes a dedicated processor and dedicated internal Flash, the TOE only provides access to the FSM/drives
once fully initialized and after receiving the administrator's password.
The TOE uses 3 crypto modules:
1. libgcrypt – used for all LUKS key management (but not encrypting/decrypting drive data)
2. Kernel – used for encrypting data on the partition
3. OpenSSL – used for verification of trusted updates