HTC A9 Secured by Cog Systems D4
(MDFPP20) Security Target
Version 0.5
May 12, 2017
Prepared for:
Cog Systems
Level 1, 277 King Street
Newtown NSW 2042
Australia
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 ..............................................................................................................................7
2. CONFORMANCE CLAIMS..............................................................................................................................8
2.1 CONFORMANCE RATIONALE...........................................................................................................................8
3. SECURITY OBJECTIVES ................................................................................................................................9
3.1 SECURITY OBJECTIVES FOR THE OPERATIONAL ENVIRONMENT .....................................................................9
4. EXTENDED COMPONENTS DEFINITION ................................................................................................10
5. SECURITY REQUIREMENTS.......................................................................................................................12
5.1 TOE SECURITY FUNCTIONAL REQUIREMENTS .............................................................................................12
5.1.1 Cryptographic support (FCS)..............................................................................................................13
5.1.2 User data protection (FDP).................................................................................................................19
5.1.3 Identification and authentication (FIA) ...............................................................................................20
5.1.4 Security management (FMT) ...............................................................................................................22
5.1.5 Protection of the TSF (FPT) ................................................................................................................25
5.1.6 TOE access (FTA)................................................................................................................................27
5.1.7 Trusted path/channels (FTP) ...............................................................................................................27
5.2 TOE SECURITY ASSURANCE REQUIREMENTS...............................................................................................27
5.2.1 Development (ADV).............................................................................................................................28
5.2.2 Guidance documents (AGD)................................................................................................................28
5.2.3 Life-cycle support (ALC) .....................................................................................................................29
5.2.4 Tests (ATE) ..........................................................................................................................................30
5.2.5 Vulnerability assessment (AVA)...........................................................................................................30
6. TOE SUMMARY SPECIFICATION..............................................................................................................32
6.1 CRYPTOGRAPHIC SUPPORT ...........................................................................................................................32
6.2 USER DATA PROTECTION ..............................................................................................................................37
6.3 IDENTIFICATION AND AUTHENTICATION.......................................................................................................39
6.4 SECURITY MANAGEMENT .............................................................................................................................41
6.5 PROTECTION OF THE TSF .............................................................................................................................41
6.6 TOE ACCESS.................................................................................................................................................43
6.7 TRUSTED PATH/CHANNELS ...........................................................................................................................44
7. TSF INVENTORY ............................................................................................................................................45
LIST OF TABLES
Table 5-1 TOE Security Functional Components........................................................................................................12
Table 5-2 Security Management Functions .................................................................................................................23
Table 5-3 Assurance Components ...............................................................................................................................28
Table 6-1 Cryptographic Providers and CAVP Certificates.......................................................................................32
Table 6-2 D4 Secure CSP Information.......................................................................................................................33
Table 6-3 Categories of System Services ....................................................................................................................38
Table 6-4 Power-up Cryptographic Algorithm Known Answer Tests ........................................................................42
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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 Secure Communications Mobile provided by Cog
Systems. The TOE is being evaluated as a mobile device.
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 – D4 Secure Mobile (MDFPP20) Security Target
ST Version – Version 0.5
ST Date – May 12, 2017
1.2 TOE Reference
TOE Identification – HTC A9 Secured by Cog Systems D4 Secure Mobile
TOE Developer – Cog Systems
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Evaluation Sponsor – Cog Systems
1.3 TOE Overview
The Target of Evaluation (TOE) is the HTC A9 Secured by Cog Systems D4 Secure Mobile device.
1.4 TOE Description
The Target of Evaluation is a smartphone based upon the HTC A9 hardware which uses Qualcomm SoCs
(Snapdragon 617, MSM8952) and runs custom Cog Systems D4 Secure images. This is a custom built smartphone
intended to support military and civil service users.
1.4.1 TOE Architecture
The TOE utilizes an OKL4 separation kernel (hypervisor), to provide 'cells' (i.e., a virtualized environment) that
virtualize and isolate different aspects of the phone's hardware. The TOE includes the Qualcomm Secure Execution
Environment (QSEE) Trustzone, the separation kernel/hypervisor, custom Cog Systems D4 Secure Mobile 'cells'
and a high-level operating system, along with the HTC One A9 hardware. While the D4 Secure Mobile can support
any operating system, the high level OS included in this evaluation is Android version 6.0.1.
The HTC One A9 hardware is based upon the Qualcomm Snapdragon 617, MSM 8952 System on a Chip (SoC).
The SoC includes a Qualcomm Integrated Cryptographic Engine (ICE) to perform encryption and decryption
operations with hardware implemented AES algorithm and software configured keys.
The custom D4 Secure Mobile ‘cells’ are shown in Figure 1-1 and described below. The OKL4 separation kernel is
also referred to as the Hypervisor. The Hypervisor create the virtualized execution environments referred to as
‘cells’ and enforces strict, pre-defined relationships for the interactions between cells. The QSEE Trustzone
provides a hardware isolated environment for cryptographic operations invoked by the Android cell and the Block
Cell (see below).
The following figure depicts the “Cells” in the running TOE and identifies the scope of this evaluation. The TOE is
packaged to include all of the pieces shown in Figure 1-1 except the 3rd
party VPN client. The “blue” boxes in
Figure 1-1 represent software that is part of the TOE. The “black” box represent the mobile device hardware.
Finally, the “white” boxes are TOE software providing functionality not included in this evaluation, which is subject
to its own separate evaluations (they do not support nor affect any of the claimed security functions).
In Figure 1-1 TOE Architecture, several cells are denoted as “Linux Cell”. This indicates that a Linux kernel is
running within the cell, providing an environment for the other functionality offered by that cell. Those boxes
labeled “C Cell” represent a cell running customized C language code.
The TOE’s Android cell includes a high-level OS. This high-level OS is a full implementation of Android 6.0.1,
modified as necessary to satisfy MDFPP20 requirements. The Android cell provides an Application Programming
Interface to mobile applications and provides users installing an application with the ability to either approve or
reject an application based upon the API access that the application requires. The Android cell provides many (but
not all) of the TOE security functions required by the MDFPP20.
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Figure 1-1 TOE Architecture
The Block Cell, is a Linux cell that provides functionality supporting the TOE security functions for Data-at-rest
protections and secure key storage. The Block Cell provides users with the ability to protect Data-At-Rest (DAR)
with AES encryption. This encompasses all user and mobile application data stored in the user's data partition. The
DAR encryption that satisfies the Data-At-Rest protection required by the MDFPP20 is provided by the Block Cell
and is referred to as the “Outer DAR” capability.
The TOE provides special protection to all user and application cryptographic keys stored in the TOE. To achieve
this, the TOE includes an Android key store within the Android cell. Android and Android applications utilize the
key store in the Android cell, which is the stock Qualcomm key master implementation.
The TOE includes the C2-Agent cell, the HSM Proxy cell, the Inner DAR cell and the Outer DIT cell that are not in
the scope of this evaluation.
Finally, like most other mobile devices, the TOE interacts with commercial Mobile Device Management systems to
allow enterprise control of the configuration and operation of the device so as to ensure adherence to enterprise-wide
policies.
1.4.1.1 Physical Boundaries
The TOE's physical boundary is the physical perimeter of the mobile device enclosure.
1.4.1.2 Logical Boundaries
This section summarizes the security functions provided by D4 Secure Mobile:
 Cryptographic support
 User data protection
 Identification and authentication
 Security management
 Protection of the TSF
 TOE access
 Trusted path/channels
1.4.1.2.1 Cryptographic support
The TOE includes multiple instances of the OpenSSL cryptographic library with CAVP validated algorithms for a
wide range of cryptographic functions including: asymmetric key generation and establishment, symmetric key
generation, encryption/decryption, cryptographic hashing and keyed-hash message authentication. These functions
are supported with suitable random bit generation, key derivation, salt generation, initialization vector generation,
secure key storage, and key and protected data destruction. These primitive cryptographic functions are used to
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implement security protocols such as TLS and HTTPS and also to encrypt the media (including the generation and
protection of data, keys, and key encryption keys) used by the TOE. Many of these cryptographic functions are also
accessible as services to applications running on the TOE.
1.4.1.2.2 User data protection
The TOE controls access to system services by hosted applications, including protection of the Trust Anchor
Database. Additionally, the TOE protects user and other sensitive data using encryption so that even if a device is
physically lost, the data remains protected.
1.4.1.2.3 Identification and authentication
The TOE supports a number of features related to identification and authentication. From a user perspective, except
for limited functions such as making phone calls to an emergency number and receiving notifications, a password
(i.e., Password Authentication Factor) must be correctly entered to unlock the TOE. Also, even when the TOE is
unlocked the password must be re-entered to change the password. Passwords are obscured when entered so they
cannot be read from the TOE's display. The TOE limits the frequency of password entry and when a configured
number of failures occurs, the TOE performs a full wipe of protected content. Passwords constructed using upper
and lower cases characters, numbers, and special characters and up to 14 characters are supported.
The TOE serves as an 802.1X supplicant and to use X509v3 certificates and perform certificate validation for a
number of functions when applicable such as EAP-TLS, TLS, and HTTPS exchanges.
1.4.1.2.4 Security management
The TOE provides all the interfaces necessary to manage the security functions claimed in the corresponding
Security Target (and conforming to the MDFPP requirements) as well as other functions commonly found in mobile
devices. Some of the available functions are available only to the mobile device users while many are restricted to
administrators operating through a Mobile Device Management solution once the TOE has been enrolled. Once the
TOE has been enrolled and then un-enrolled, it performs functions such as performing a full wipe of protected data
to complete the unenrollment.
1.4.1.2.5 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 particularly sensitive data such as cryptographic keys so that they are not accessible or
exportable. It has access to a timing mechanism to ensure that reliable time information is available (e.g., for
cryptographic operations and perhaps user accountability). It enforces read, write, and execute memory page
protections, use address space layout randomization, and use stack-based buffer overflow protections to minimize
the potential to exploit application flaws. It is to protect itself from modification by applications as well as to isolate
the address spaces of applications from one another to protect those applications. The TOE employs a Secure Boot
process that uses cryptographic signatures to ensure the authenticity and integrity of the bootloader, and the secure
boot partition produced by Cog. The cryptographic signatures utilize data fused into the device processor.
The TOE 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 self-test fails, the TOE does not go into an operational mode. It also
includes mechanisms (i.e., verification of the digital signature of each new image) so that the TOE itself can be
updated while ensuring that the updates will not introduce malicious or other unexpected changes in the TOE.
Digital signature checking also extends to verifying applications prior to their installation.
1.4.1.2.6 TOE access
The TOE can be locked, obscuring its display, by a user or after a configured interval of inactivity. The TOE has the
capability to display an advisory message (banner) when users unlock the TOE for use.
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The TOE is able to attempt to connect to wireless networks as configured.
1.4.1.2.7 Trusted path/channels
The TOE supports the use of 802.11-2012, 802.1X, HTTPS/TLS and EAP-TLS to secure communications channels
between itself and other trusted network devices.
1.4.2 TOE Documentation
 HTC One A9, Secured by D4, Administrator guide Instructions, 6 March 2017, Version 0.34
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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,
Version 3.1, Revision 4, September 2012.
 Part 2 Extended
 Common Criteria for Information Technology Security Evaluation Part 3: Security assurance components,
Version 3.1 Revision 4, September 2012.
 Part 3 Extended
 Package Claims:
 Protection Profile For Mobile Device Fundamentals, Version 2.0, 17 September 2014
(MDFPP20)
2.1 Conformance Rationale
The ST conforms to the MDFPP20. 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 MDFPP20 and this section reproduces only the corresponding
Security Objectives for operational environment for reader convenience. The MDFPP20 offers additional
information about the identified security objectives, but that has not been reproduced here and the MDFPP20 should
be consulted if there is interest in that material.
In general, the MDFPP20 has defined Security Objectives appropriate for mobile device and as such are applicable
to the Secure Communications Mobile TOE.
3.1 Security Objectives for the Operational Environment
OE.CONFIG TOE administrators will configure the Mobile Device security functions correctly to create the
intended security policy.
OE.NOTIFY The Mobile User will immediately notify the administrator if the Mobile Device is lost or stolen.
OE.PRECAUTION The Mobile User exercises precautions to reduce the risk of loss or theft of the Mobile Device.
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4. Extended Components Definition
All of the extended requirements in this ST have been drawn from the MDFPP20. The MDFPP20 defines the
following extended requirements and since they are not redefined in this ST the MDFPP20 should be consulted for
more information in regard to those CC extensions.
Extended SFRs:
- FCS_CKM_EXT.1: Extended: Cryptographic Key Support
- FCS_CKM_EXT.2: Extended: Cryptographic Key Random Generation
- FCS_CKM_EXT.3: Extended: Cryptographic Key Generation
- FCS_CKM_EXT.4: Extended: Key Destruction
- FCS_CKM_EXT.5: Extended: TSF Wipe
- FCS_CKM_EXT.6: Extended: Salt Generation
- FCS_HTTPS_EXT.1: Extended: HTTPS Protocol
- FCS_IV_EXT.1: Extended: Initialization Vector Generation
- FCS_RBG_EXT.1: Extended: Cryptographic Operation (Random Bit Generation)
- FCS_SRV_EXT.1: Extended: Cryptographic Algorithm Services
- FCS_STG_EXT.1: Extended: Cryptographic Key Storage
- FCS_STG_EXT.2: Extended: Encrypted Cryptographic Key Storage
- FCS_STG_EXT.3: Extended: Integrity of encrypted key storage
- FCS_TLSC_EXT.1: Extended: EAP TLS Protocol
- FCS_TLSC_EXT.2: Extended: TLS Protocol
- FDP_ACF_EXT.1: Extended: Security access control
- FDP_DAR_EXT.1: Extended: Protected Data Encryption
- FDP_IFC_EXT.1: Extended: Subset information flow control
- FDP_STG_EXT.1: Extended: User Data Storage
- FDP_UPC_EXT.1: Extended: Inter-TSF user data transfer protection
- FIA_AFL_EXT.1: Authentication failure handling
- FIA_BLT_EXT.1: Extended: Bluetooth User Authorization
- FIA_PAE_EXT.1: Extended: PAE Authentication
- FIA_PMG_EXT.1: Extended: Password Management
- FIA_TRT_EXT.1: Extended: Authentication Throttling
- FIA_UAU_EXT.1: Extended: Authentication for Cryptographic Operation
- FIA_UAU_EXT.2: Extended: Timing of Authentication
- FIA_UAU_EXT.3: Extended: Re-Authentication
- FIA_X509_EXT.1: Extended: Validation of certificates
- FIA_X509_EXT.2: Extended: X509 certificate authentication
- FIA_X509_EXT.3: Extended: Request Validation of certificates
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- FMT_MOF_EXT.1: Extended: Management of security functions behavior
- FMT_SMF_EXT.1: Extended: Specification of Management Functions
- FMT_SMF_EXT.2: Extended: Specification of Remediation Actions
- FPT_AEX_EXT.1: Extended: Anti-Exploitation Services (ASLR)
- FPT_AEX_EXT.2: Extended: Anti-Exploitation Services (Memory Page Permissions)
- FPT_AEX_EXT.3: Extended: Anti-Exploitation Services (Overflow Protection)
- FPT_AEX_EXT.4: Extended: Domain Isolation
- FPT_KST_EXT.1: Extended: Key Storage
- FPT_KST_EXT.2: Extended: No Key Transmission
- FPT_KST_EXT.3: Extended: No Plaintext Key Export
- FPT_NOT_EXT.1: Extended: Self-Test Notification
- FPT_TST_EXT.1: Extended: TSF Cryptographic Functionality Testing
- FPT_TST_EXT.2: Extended: TSF Integrity Testing
- FPT_TUD_EXT.1: Extended: Trusted Update: TSF version query
- FPT_TUD_EXT.2: Extended: Trusted Update Verification
- FTA_SSL_EXT.1: Extended: TSF- and User-initiated locked state
- FTA_WSE_EXT.1: Extended: Wireless Network Access
- FTP_ITC_EXT.1: Extended: Trusted channel Communication
Extended SARs:
- ALC_TSU_EXT.1: Timely Security Updates
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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 MDFPP20. The refinements and operations already performed in the
MDFPP20 are not identified (e.g., highlighted) here, rather the requirements have been copied from the MDFPP20
and any residual operations have been completed herein. Of particular note, the MDFPP20 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 MDFPP20 which includes all the SARs for EAL 1. However, the SARs are
effectively refined since requirement-specific 'Assurance Activities' are defined in the MDFPP20 that serve to
ensure corresponding evaluations will yield more practical and consistent assurance than the EAL 1 assurance
requirements alone. The MDFPP20 should be consulted for the assurance activity definitions.
5.1 TOE Security Functional Requirements
The following table identifies the SFRs that are satisfied by Secure Communications Mobile TOE.
Table 5-1 TOE Security Functional Components
Requirement Class Requirement Component
FCS: Cryptographic support FCS_CKM.1(1): Cryptographic key generation
FCS_CKM.1(2): Cryptographic key generation
FCS_CKM.2(1): Cryptographic key establishment
FCS_CKM.2(2): Cryptographic key distribution
FCS_CKM_EXT.1: Extended: Cryptographic Key Support
FCS_CKM_EXT.2: Extended: Cryptographic Key Random
Generation
FCS_CKM_EXT.3: Extended: Cryptographic Key Generation
FCS_CKM_EXT.4: Extended: Key Destruction
FCS_CKM_EXT.5: Extended: TSF Wipe
FCS_CKM_EXT.6: Extended: Salt Generation
FCS_COP.1(1): Cryptographic operation
FCS_COP.1(2): Cryptographic operation
FCS_COP.1(3): Cryptographic operation
FCS_COP.1(4): Cryptographic operation
FCS_COP.1(5): Cryptographic operation
FCS_HTTPS_EXT.1: Extended: HTTPS Protocol
FCS_IV_EXT.1: Extended: Initialization Vector Generation
FCS_RBG_EXT.1: Extended: Cryptographic Operation (Random Bit
Generation)
FCS_SRV_EXT.1: Extended: Cryptographic Algorithm Services
FCS_STG_EXT.1: Extended: Cryptographic Key Storage
FCS_STG_EXT.2: Extended: Encrypted Cryptographic Key Storage
FCS_STG_EXT.3: Extended: Integrity of encrypted key storage
FCS_TLSC_EXT.1: Extended: EAP TLS Protocol
FCS_TLSC_EXT.2: Extended: TLS Protocol
FDP: User data protection FDP_ACF_EXT.1: Extended: Security access control
FDP_DAR_EXT.1: Extended: Protected Data Encryption
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FDP_IFC_EXT.1: Extended: Subset information flow control
FDP_STG_EXT.1: Extended: User Data Storage
FDP_UPC_EXT.1: Extended: Inter-TSF user data transfer protection
FIA: Identification and
authentication
FIA_AFL_EXT.1: Authentication failure handling
FIA_BLT_EXT.1: Extended: Bluetooth User Authorization
FIA_PAE_EXT.1: Extended: PAE Authentication
FIA_PMG_EXT.1: Extended: Password Management
FIA_TRT_EXT.1: Extended: Authentication Throttling
FIA_UAU.7: Protected authentication feedback
FIA_UAU_EXT.1: Extended: Authentication for Cryptographic
Operation
FIA_UAU_EXT.2: Extended: Timing of Authentication
FIA_UAU_EXT.3: Extended: Re-Authentication
FIA_X509_EXT.1: Extended: Validation of certificates
FIA_X509_EXT.2: Extended: X509 certificate authentication
FIA_X509_EXT.3: Extended: Request Validation of certificates
FMT: Security management FMT_MOF_EXT.1: Extended: Management of security functions
behavior
FMT_SMF_EXT.1: Extended: Specification of Management
Functions
FMT_SMF_EXT.2: Extended: Specification of Remediation Actions
FPT: Protection of the TSF FPT_AEX_EXT.1: Extended: Anti-Exploitation Services (ASLR)
FPT_AEX_EXT.2: Extended: Anti-Exploitation Services (Memory
Page Permissions)
FPT_AEX_EXT.3: Extended: Anti-Exploitation Services (Overflow
Protection)
FPT_AEX_EXT.4: Extended: Domain Isolation
FPT_BBD_EXT.1: Application Processor Mediation
FPT_KST_EXT.1: Extended: Key Storage
FPT_KST_EXT.2: Extended: No Key Transmission
FPT_KST_EXT.3: Extended: No Plaintext Key Export
FPT_NOT_EXT.1: Extended: Self-Test Notification
FPT_STM.1: Reliable time stamps
FPT_TST_EXT.1: Extended: TSF Cryptographic Functionality
Testing
FPT_TST_EXT.2: Extended: TSF Integrity Testing
FPT_TUD_EXT.1: Extended: Trusted Update: TSF version query
FPT_TUD_EXT.2: Extended: Trusted Update Verification
FTA: TOE access FTA_SSL_EXT.1: Extended: TSF- and User-initiated locked state
FTA_TAB.1: TOE Access Banner
FTA_WSE_EXT.1: Extended: Wireless Network Access
FTP: Trusted path/channels FTP_ITC_EXT.1: Extended: Trusted channel Communication
5.1.1 Cryptographic support (FCS)
5.1.1.1 Cryptographic key generation (FCS_CKM.1(1))
FCS_CKM.1(1).1
The application shall generate asymmetric cryptographic keys in accordance with a specified
cryptographic key generation algorithm [
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ECC schemes using 'NIST curves' P-256, P-384 and [P-521] that meet the following: FIPS
PUB 186-4, 'Digital Signature Standard (DSS)', Appendix B.4,
FFC schemes using cryptographic key sizes of 2048-bit or greater that meet the following:
FIPS PUB 186-4, 'Digital Signature Standard (DSS)', Appendix B.1]
5.1.1.2 Cryptographic key generation (FCS_CKM.1(2))
FCS_CKM.1(2).1
The TSF shall generate symmetric cryptographic keys in accordance with a specified
cryptographic key generation algorithm [PRF-384] and specified cryptographic key sizes [128
bits] using a Random Bit Generator as specified in FCS_RBG_EXT.1 that meet the following:
[IEEE 802.11-2012].
5.1.1.3 Cryptographic key establishment (FCS_CKM.2(1))
FCS_CKM.2(1).1
The TSF shall perform cryptographic key establishment in accordance with a specified
cryptographic key establishment method: [
RSA-based key establishment schemes that meets the following: NIST Special Publication
800-56B, 'Recommendation for Pair-Wise Key Establishment Schemes Using Integer
Factorization Cryptography',
Elliptic curve-based key establishment schemes that meets the following: [NIST Special
Publication 800-56A, 'Recommendation for Pair-Wise Key Establishment Schemes Using
Discrete Logarithm Cryptography'],
Finite field-based key establishment schemes that meets the following: NIST Special
Publication 800-56A, 'Recommendation for Pair-Wise Key Establishment Schemes Using
Discrete Logarithm Cryptography']
for the purposes of encrypting sensitive data received while the device is locked. (TD0048
applied)
5.1.1.4 Cryptographic key distribution (FCS_CKM.2(2))
FCS_CKM.2(2).1
The TSF shall decrypt Group Temporal Key (GTK) in accordance with a specified cryptographic
key distribution method [AES Key Wrap in an EAPOL-Key frame] that meets the following:
[NIST SP 800-38F, IEEE 802.11-2012 for the packet format and timing considerations] and does
not expose the cryptographic keys.
5.1.1.5 Extended: Cryptographic Key Support (FCS_CKM_EXT.1)
FCS_CKM_EXT.1.1
The TSF shall support a [hardware-isolated] REK with a [symmetric] key of strength [256 bits].
(TD0038 applied)
FCS_CKM_EXT.1.2
System software on the TSF shall be able only to request [NIST SP 800-108 key derivation] by
the key and shall not be able to read, import, or export a REK. (TD0038 applied)
FCS_CKM_EXT.1.3
A REK shall be generated by a RBG in accordance with FCS_RBG_EXT.1.
5.1.1.6 Extended: Cryptographic Key Random Generation (FCS_CKM_EXT.2)
FCS_CKM_EXT.2.1
All DEKs shall be randomly generated with entropy corresponding to the security strength of AES
key sizes of [128, 256] bits.
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5.1.1.7 Extended: Cryptographic Key Generation (FCS_CKM_EXT.3)
FCS_CKM_EXT.3.1
The TSF shall use [[256-bit] symmetric KEKs] corresponding to at least the security strength of
the keys encrypted by the KEK. (TD0038 applied)
FCS_CKM_EXT.3.2
The TSF shall generate all KEKs using one or more of the following methods:
a) derive the KEK from a Password Authentication Factor using PBKDF and [
b) generate the KEK using an RBG that meets this profile (as specified in
FCS_RBG_EXT.1),
c) generate the KEK using a key generation scheme that meets this profile (as specified in
FCS_CKM.1(1)) (Per TD0038),
d) Combine the KEK from other KEKs in a way that preserves the effective entropy of
each factor by [encrypting one key with another] (Per TD0038)].
5.1.1.8 Extended: Key Destruction (FCS_CKM_EXT.4)
FCS_CKM_EXT.4.1
The TSF shall destroy cryptographic keys in accordance with the specified cryptographic key
destruction methods:
- by clearing the KEK encrypting the target key,
- in accordance with the following rules:
 For volatile memory, the destruction shall be executed by a single direct overwrite
[consisting of zeroes]. (TD0028 applied)
 For non-volatile EEPROM, the destruction shall be executed by a single direct
overwrite consisting of a pseudo random pattern using the TSF's RBG (as specified in
FCS_RBG_EXT.1), followed a read-verify.
 For non-volatile flash memory that is not wear-leveled, the destruction shall be
executed [by a block erase that erases the reference to memory that stores data as
well as the data itself]. (TD0057 applied)
 For non-volatile flash memory that is wear-leveled, the destruction shall be executed
[by a block erase].
 For non-volatile memory other than EEPROM and flash, the destruction shall be
executed by overwriting three or more times with a random pattern that is changed
before each write. (TD0047 applied)
FCS_CKM_EXT.4.2
The TSF shall destroy all plaintext keying material and critical security parameters when no longer
needed.
5.1.1.9 Extended: TSF Wipe (FCS_CKM_EXT.5)
FCS_CKM_EXT.5.1
The TSF shall wipe all protected data by [
- Cryptographically erasing the encrypted DEKs and/or the KEKs in non-volatile
memory by following the requirements in FCS_CKM_EXT.4.1;].
FCS_CKM_EXT.5.2
The TSF shall perform a power cycle on conclusion of the wipe procedure.
5.1.1.10 Extended: Salt Generation (FCS_CKM_EXT.6)
FCS_CKM_EXT.6.1
The TSF shall generate all salts using a RBG that meets FCS_RBG_EXT.1.
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5.1.1.11 Cryptographic operation (FCS_COP.1(1))
FCS_COP.1(1).1
The TSF shall perform [encryption/decryption] in accordance with a specified cryptographic
algorithm
 AES-CBC (as defined in FIPS PUB 197, and NIST SP 800-38A) mode,
 AES-CCMP (as defined in FIPS PUB 197, NIST SP 800-38C and IEEE 802.11-2012), and
 [AES-CCM (as defined in NIST SP 800-38C),
 AES-XTS (as defined in NIST SP 800-38E) mode]
and cryptographic key sizes 128-bit key sizes and [256-bit key sizes].
5.1.1.12 Cryptographic operation (FCS_COP.1(2))
FCS_COP.1(2).1
The TSF shall perform [cryptographic hashing] in accordance with a specified cryptographic
algorithm SHA-1 and [SHA-256, SHA-384, SHA-512] and message digest sizes 160 and [256,
384, 512] that meet the following: [FIPS Pub 180-4].
5.1.1.13 Cryptographic operation (FCS_COP.1(3))
FCS_COP.1(3).1
The TSF shall perform [cryptographic signature services (generation and verification)] in
accordance with a specified cryptographic algorithm
 [RSA schemes] using cryptographic key sizes [of 2048-bit or greater] that meet the
following: [FIPS PUB 186-4, 'Digital Signature Standard (DSS)', Section 4]
and [
 [ECDSA schemes] using ['NIST curves' P-256, P-384 and [P-521]] that meet the
following: [FIPS PUB 186-4, 'Digital Signature Standard (DSS)', Section 5];].
5.1.1.14 Cryptographic operation (FCS_COP.1(4))
FCS_COP.1(4).1
The TSF shall perform [keyed-hash message authentication] in accordance with a specified
cryptographic algorithm HMAC-SHA-1 and [HMAC-SHA-256, HMAC-SHA-384, HMAC-SHA-
512] and cryptographic key sizes [160, 256, 384, 512] and message digest sizes 160 and [256, 384,
512] bits that meet the following: [FIPS Pub 198-1, 'The Keyed-Hash Message Authentication
Code', and FIPS Pub 180-4, 'Secure Hash Standard'].
5.1.1.15 Cryptographic operation (FCS_COP.1(5))
FCS_COP.1(5).1
The TSF shall perform [Password-based Key Derivation Functions] in accordance with a specified
cryptographic algorithm [HMAC-[SHA-256]], with [10000] iterations, and output cryptographic
key sizes [256] that meet the following: [NIST SP 800-132].
5.1.1.16 Extended: HTTPS Protocol (FCS_HTTPS_EXT.1)
FCS_HTTPS_EXT.1.1
The TSF shall implement the HTTPS protocol that complies with RFC 2818.
FCS_HTTPS_EXT.1.2
The TSF shall implement HTTPS using TLS (FCS_TLSC_EXT.2).
FCS_HTTPS_EXT.1.3
The TSF shall notify the application and [not establish the connection] if the peer certificate is
deemed invalid.
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5.1.1.17 Extended: Initialization Vector Generation (FCS_IV_EXT.1)
FCS_IV_EXT.1.1
The TSF shall generate IVs in accordance with MDFPP20 Table 14: References and IV
Requirements for NIST-approved Cipher Modes.
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 NIST
Special Publication 800-90A using [CTR_DRBG (AES)]. (TD0079 applied)
FCS_RBG_EXT.1.2
The deterministic RBG shall be seeded by an entropy source that accumulates entropy from [TSF-
hardware-based noise source] with a minimum of [256 bits] of entropy at least equal to the
greatest security strength (according to NIST SP 800-57) of the keys and hashes that it will
generate.
FCS_RBG_EXT.1.3
The TSF shall be capable of providing output of the RBG to applications running on the TSF that
request random bits.
5.1.1.19 Extended: Cryptographic Algorithm Services (FCS_SRV_EXT.1)
FCS_SRV_EXT.1.1
The TSF shall provide a mechanism for applications to request the TSF to perform the following
cryptographic operations:
 All mandatory and [(per TD0059) selected algorithms] in FCS_CKM.2(1),
 The following algorithms in FCS_COP.1(1): AES-CBC, [no other modes]
 All mandatory and selected algorithms in FCS_COP.1(3)
 All mandatory and selected algorithms in FCS_COP.1(2)
 All mandatory and selected algorithms in FCS_COP.1(4) [
 All mandatory and [(per TD0059) selected algorithms] in FCS_CKM.1(1),
 The selected algorithms in FCS_COP.1(5)].
5.1.1.20 Extended: Cryptographic Key Storage (FCS_STG_EXT.1)
FCS_STG_EXT.1.1
The TSF shall provide [hardware-isolated] secure key storage for asymmetric private keys and
[symmetric keys].
FCS_STG_EXT.1.2
The TSF shall be capable of importing keys/secrets into the secure key storage upon request of
[the user] and [applications running on the TSF].
FCS_STG_EXT.1.3
The TSF shall be capable of destroying keys/secrets in the secure key storage upon request of [the
user].
FCS_STG_EXT.1.4
The TSF shall have the capability to allow only the application that imported the key/secret the
use of the key/secret. Exceptions may only be explicitly authorized by [a common application
developer].
FCS_STG_EXT.1.5
The TSF shall allow only the application that imported the key/secret to request that the key/secret
be destroyed. Exceptions may only be explicitly authorized by [a common application developer].
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5.1.1.21 Extended: Encrypted Cryptographic Key Storage (FCS_STG_EXT.2)
FCS_STG_EXT.2.1
The TSF shall encrypt all DEKs and KEKs and [long-term trusted channel key material] by
KEKs that are [
1) Protected by the REK with [
b. encryption by a KEK chaining to a REK],
2) Protected by the REK and the password with [
b. encryption by a KEK chaining to a REK and the password-derived KEK]].
FCS_STG_EXT.2.2
DEKs and KEKs and [long-term trusted channel key material] shall be encrypted using one of
the following methods: [
using a SP800-56B key establishment scheme,
using AES in the [GCM, CBC mode]]. (TD0038 applied)
5.1.1.22 Extended: Integrity of encrypted key storage (FCS_STG_EXT.3)
FCS_STG_EXT.3.1
The TSF shall protect the integrity of any encrypted DEKs and KEKs and [no other keys] by [
- [GCM] cipher mode for encryption according to FCS_STG_EXT.2
- a keyed hash (FCS_COP.1(4)) using a key protected by a key protected by
FCS_STG_EXT.2].
FCS_STG_EXT.3.2
The TSF shall verify the integrity of the [hash] of the stored key prior to use of the key.
5.1.1.23 Extended: EAP TLS Protocol (FCS_TLSC_EXT.1)
FCS_TLSC_EXT.1.1
The TSF shall implement TLS 1.0 and [TLS 1.1 (RFC 4346)] supporting the following
ciphersuites:
- Mandatory Ciphersuites:
 TLS_RSA_WITH_AES_128_CBC_SHA as defined in RFC 5246
- [Optional Ciphersuites:
 TLS_RSA_WITH_AES_256_CBC_SHA as defined in RFC 5246,
 TLS_DHE_RSA_WITH_AES_128_CBC_SHA as defined in RFC 5246,
 TLS_DHE_RSA_WITH_AES_256_CBC_SHA as defined in RFC 5246,
 TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA as defined in RFC 4492,
 TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA as defined in RFC 4492,
 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA as defined in RFC 4492,
 TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA as defined in RFC 4492,
 TLS_RSA_WITH_AES_128_CBC_SHA256 as defined in RFC 5246,
 TLS_RSA_WITH_AES_256_CBC_ SHA256 as defined in RFC 5246,
 TLS_DHE_RSA_WITH_AES_128_CBC_ SHA256 as defined in RFC 5246,
 TLS_DHE_RSA_WITH_AES_256_CBC_ SHA256 as defined in RFC 5246,
 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 as defined in RFC 5289,
 TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 as defined in RFC 5289,
 TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 as defined in RFC 5289,
 TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 as defined in RFC 5289,
].
FCS_TLSC_EXT.1.2
The TSF shall verify that the server certificate presented for EAP-TLS [chains to one of the
specified CAs].
FCS_TLSC_EXT.1.3
The TSF shall not establish a trusted channel if the peer certificate is invalid.
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FCS_TLSC_EXT.1.4
The TSF shall support mutual authentication using X.509v3 certificates.
FCS_TLSC_EXT.1.5
The TSF shall present the Supported Elliptic Curves Extension in the Client Hello with the
following NIST curves: [secp256r1, secp384r1, secp521r1] and no other curves.
5.1.1.24 Extended: TLS Protocol (FCS_TLSC_EXT.2)
FCS_TLSC_EXT.2.1
The TSF shall implement TLS 1.2 (RFC 5246) supporting the following ciphersuites:
- Mandatory Ciphersuites:
 TLS_RSA_WITH_AES_128_CBC_SHA as defined in RFC 5246
- [Optional Ciphersuites:
 TLS_RSA_WITH_AES_256_CBC_SHA as defined in RFC 5246,
 TLS_DHE_RSA_WITH_AES_128_CBC_SHA as defined in RFC 5246,
 TLS_DHE_RSA_WITH_AES_256_CBC_SHA as defined in RFC 5246,
 TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA as defined in RFC 4492,
 TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA as defined in RFC 4492,
 TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA as defined in RFC 4492,
 TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA as defined in RFC 4492,
 TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 as defined in RFC 5289,
 TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 as defined in RFC 5289,
].
FCS_TLSC_EXT.2.2
The TSF shall verify that the presented identifier matches the reference identifier according to
RFC 6125.
FCS_TLSC_EXT.2.3
The TSF shall not establish a trusted channel if the peer certificate is invalid.
FCS_TLSC_EXT.2.4
The TSF shall support mutual authentication using X.509v3 certificates.
FCS_TLSC_EXT.2.5
The TSF shall present the Supported Elliptic Curves Extension in the Client Hello with the
following NIST curves: [secp256r1, secp384r1, secp521r1] and no other curves.
ST Author Note: FCS_TLSC_EXT.2.6 is no longer required to meet Use Case #2 (“Enterprise-owned device for
specialized, high-security use”), as detailed in section G.2 of the Protection Profile for Mobile
Devices v2.0. [TD0091]
5.1.2 User data protection (FDP)
5.1.2.1 Extended: Security access control (FDP_ACF_EXT.1)
FDP_ACF_EXT.1.1
The TSF shall provide a mechanism to restrict the system services that are accessible to an
application.
FDP_ACF_EXT.1.2
The TSF shall provide an access control policy that prevents [groups of application processes]
from accessing [all] data stored by other [groups of application processes]. Exceptions may only
be explicitly authorized for such sharing by [a common application developer].
5.1.2.2 Extended: Protected Data Encryption (FDP_DAR_EXT.1)
FDP_DAR_EXT.1.1
Encryption shall cover all protected data.
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FDP_DAR_EXT.1.2
Encryption shall be performed using DEKs with AES in the [XTS] mode with key size [128] bits.
5.1.2.3 Extended: Subset information flow control (FDP_IFC_EXT.1)
FDP_IFC_EXT.1.1
The TSF shall [provide an interface to VPN clients to enable all IP traffic (other than IP traffic
required to establish the VPN connection) to flow through the IPsec VPN client].
5.1.2.4 Extended: User Data Storage (FDP_STG_EXT.1)
FDP_STG_EXT.1.1
The TSF shall provide protected storage for the Trust Anchor Database.
5.1.2.5 Extended: Inter-TSF user data transfer protection (FDP_UPC_EXT.1)
FDP_UPC_EXT.1.1
The TSF provide a means for non-TSF applications executing on the TOE to use TLS, HTTPS,
Bluetooth BR/EDR, and [no other protocol] to provide a protected communication channel
between the non-TSF application and another IT product that is logically distinct from other
communication channels, provides assured identification of its end points, protects channel data
from disclosure, and detects modification of the channel data.
FDP_UPC_EXT.1.2
The TSF shall permit the non-TSF applications to initiate communication via the trusted channel.
5.1.3 Identification and authentication (FIA)
5.1.3.1 Authentication failure handling (FIA_AFL_EXT.1)
FIA_AFL_EXT.1.1
The TSF shall detect when a configurable positive integer within [1 and 10] of unsuccessful
authentication attempts occur related to last successful authentication by that user.
FIA_AFL_EXT.1.2
When the defined number of unsuccessful authentication attempts has been surpassed, the TSF
shall perform wipe of all protected data.
FIA_AFL_EXT.1.3
The TSF shall maintain the number of unsuccessful authentication attempts that have occurred
upon power off.
5.1.3.2 Extended: Bluetooth User Authorization (FIA_BLT_EXT.1)
FIA_BLT_EXT.1.1
The TSF shall require explicit user authorization before pairing with a remote Bluetooth device.
5.1.3.3 Extended: PAE Authentication (FIA_PAE_EXT.1)
FIA_PAE_EXT.1.1
The TSF shall conform to IEEE Standard 802.1X for a Port Access Entity (PAE) in the
'Supplicant' role.
5.1.3.4 Extended: Password Management (FIA_PMG_EXT.1)
FIA_PMG_EXT.1.1
The TSF shall support the following for the Password Authentication Factor: 1. Passwords shall be
able to be composed of any combination of [upper and lower case letters], numbers, and special
characters: [[“!”, “@”, “#”, “$”, “%”, “^”, “&”, “*”, “(“, “)”, “+”, “=”, “_”, “/”, “-“, “’”, “””,
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“:”, “;”, “,”, “?”, “`”, “~”, “\”, “|”, “<”, “>”, “{“, “}”, “[“, “]”]]; 2. Password length up to [16]
characters shall be supported.
5.1.3.5 Extended: Authentication Throttling (FIA_TRT_EXT.1)
FIA_TRT_EXT.1.1
The TSF shall limit automated user authentication attempts by [enforcing a delay between
incorrect authentication attempts]. The minimum delay shall be such that no more than 10
attempts can be attempted per 500 milliseconds.
5.1.3.6 Protected authentication feedback (FIA_UAU.7)
FIA_UAU.7.1
The TSF shall provide only [obscured feedback to the device's display] to the user while the
authentication is in progress.
5.1.3.7 Extended: Authentication for Cryptographic Operation (FIA_UAU_EXT.1)
FIA_UAU_EXT.1.1
The TSF shall require the user to present the Password Authentication Factor prior to decryption
of protected data and encrypted DEKs, KEKs and [long-term trusted channel key material] at
startup.
5.1.3.8 Extended: Timing of Authentication (FIA_UAU_EXT.2)
FIA_UAU_EXT.2.1
The TSF shall allow [
 enter password to unlock,
 turn off or Restart the TOE,
 see the configured banner,
 toggle the Do Not Disturb and Auto Rotate function,
 make/receive an emergency call,
 receive an incoming phone calls,
 take screen shots,
 enable or disable airplane mode,
 configure sound/vibrate/mute,
 use a flashlight,
 use Voice assist ,
 access widget functions, and
 view notifications
] on behalf of the user to be performed before the user is authenticated.
FIA_UAU_EXT.2.2
The TSF shall require each user to be successfully authenticated before allowing any other TSF-
mediated actions on behalf of that user.
Application Note: Some notifications identify actions, for example to view a screenshot; however, selecting
those notifications highlights the password prompt and require the password to access that
data.
5.1.3.9 Extended: Re-Authentication (FIA_UAU_EXT.3)
FIA_UAU_EXT.3.1
The TSF shall require the user to enter the correct Password Authentication Factor when the user
changes the Password Authentication Factor, and following TSF- and user-initiated locking in
order to transition to the unlocked state, and [no other conditions].
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5.1.3.10 Extended: Validation of certificates (FIA_X509_EXT.1)
FIA_X509_EXT.1.1
The TSF shall validate certificates in accordance with the following rules:
- RFC 5280 certificate validation and certificate path validation.
- The certificate path must terminate with a certificate in the Trust Anchor Database.
- The TSF shall validate a certificate path by ensuring the presence of the basicConstraints
extension and that the CA flag is set to TRUE for all CA certificates.
- The TSF shall validate the revocation status of the certificate using [a Certificate Revocation
List (CRL) as specified in RFC 5759].
- The TSF shall validate the extendedKeyUsage field according to the following rules:
o Certificates used for trusted updates and executable code integrity verification shall have
the Code Signing purpose (id-kp 3 with OID 1.3.6.1.5.5.7.3.3) in the extendedKeyUsage
field.
o Server certificates presented for TLS shall have the Server Authentication purpose (id-kp
1 with OID 1.3.6.1.5.5.7.3.1) in the extendedKeyUsage field.
o (Conditional) Server certificates presented for EST shall have the CMC Registration
Authority (RA) purpose (id-kp-cmcRA with OID 1.3.6.1.5.5.7.3.28) in the
extendedKeyUsage field.
FIA_X509_EXT.1.2
The TSF shall only treat a certificate as a CA certificate if the basicConstraints extension is
present and the CA flag is set to TRUE.
5.1.3.11 Extended: X509 certificate authentication (FIA_X509_EXT.2)
FIA_X509_EXT.2.1
The TSF shall use X.509v3 certificates as defined by RFC 5280 to support authentication for
EAP-TLS exchanges, and [TLS, HTTPS], and [no additional uses].
FIA_X509_EXT.2.2
When the TSF cannot establish a connection to determine the validity of a certificate, the TSF
shall [accept the certificate and not accept the certificate].
Application Note: The TOE EAP-TLS implementation accepts the certificate when the revocation server cannot
be reached, and the TOE TLS and HTTPS implementations reject the certificate when the
revocation server cannot be reached.
5.1.3.12 Extended: Request Validation of certificates (FIA_X509_EXT.3)
FIA_X509_EXT.3.1
The TSF shall provide a certificate validation service to applications.
FIA_X509_EXT.3.2
The TSF shall respond to the requesting application with the success or failure of the validation.
5.1.4 Security management (FMT)
5.1.4.1 Extended: Management of security functions behavior (FMT_MOF_EXT.1)
FMT_MOF_EXT.1.1
The TSF shall restrict the ability to perform the functions in column 3 of Table 1 Table 5-2
Security Management Functions to the user.
FMT_MOF_EXT.1.2
The TSF shall restrict the ability to perform the functions in column 5 of Table 1 Table 5-2
Security Management Functions to the administrator when the device is enrolled and according to
the administrator-configured policy.
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5.1.4.2 Extended: Specification of Management Functions (FMT_SMF_EXT.1)
FMT_SMF_EXT.1.1
The TSF shall be capable of performing the following management functions: in column 2 of
Table 5-2 Security Management Functions.
FMT_SMF_EXT.1.2
The TSF shall be capable of allowing the administrator to perform the functions in column 4
of Table 5-2 Security Management Functions.
Table 5-2 Security Management Functions
Management Function
FMT_SMF_EXT.1.1
FMT_MOF_EXT.1.1
FMT_SMF_EXT.1.2
FMT_MOF_EXT.1.2
1. configure password policy:
a. minimum password length
b. minimum password complexity
c. maximum password lifetime
The administrator can configure the required password characteristics (minimum length,
complexity, and lifetime) using the Android MDM APIs.
M - M M
2. configure session locking policy:
a. screen-lock enabled/disabled
b. screen lock timeout
c. number of authentication failures
The administrator can configure the session locking policy using the Android MDM APIs.
The user can also adjust each of the session locking policies; however, if set by the
administrator, the user can only set a more strict policy (e.g., setting the device to allow
fewer authentication failures than configured by the administrator).
M - M M
3. enable/disable the VPN protection:
a. across device
c. [no other method]
M - I I
4. enable/disable [Wifi, Bluetooth, and Cellular radios] M - - -
5. enable/disable [camera, microphone]: (TD0044 applied)
a. across device
c. [no other method]
M - M
I
M
I
6. specify wireless networks (SSIDs) to which the TSF may connect (TD0064 applied) M
I
- M
I
-
7. configure security policy for each wireless network:
a. [specify the CA(s) from which the TSF will accept WLAN authentication
server certificate(s)]
b. security type
c. authentication protocol
d. client credentials to be used for authentication
M - M -
8. transition to the locked state M - M -
9. full wipe of protected data M - M -
10. configure application installation policy by [ M - M M
Status Markers:
M – Mandatory
O – Optional/Objective
Status Markers:
M – Mandatory
I – Implemented
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a. specifying authorized application repository(s),
b. denying installation of applications ]
11. import keys/secrets into the secure key storage M I - -
12. destroy imported keys/secrets and [no other keys/secrets] in the secure key storage M I - -
13. import X.509v3 certificates into the Trust Anchor Database M - M -
14. remove imported X.509v3 certificates and [all other X.509v3 certificates] in the
Trust Anchor Database
M - - -
15. enroll the TOE in management (TD0058 applied) M M O
-
-
16. remove applications M - M -
17. update system software M - M -
18. install applications M - M -
19. remove Enterprise applications M - M -
20. configure the Bluetooth trusted channel:
a. disable/enable the Discoverable mode (for BR/EDR)
b. change the Bluetooth device name
c. [no other Bluetooth configuration]
M - - -
21. enable/disable display notification in the locked state of: [all notifications] M - I I
22. enable/disable all data signaling over [assignment: list of externally accessible
hardware ports]
- - - -
23. enable/disable [assignment: list of protocols where the device acts as a server =
Protocols supporting wireless remote access = all protocols where the device acts as a
server]
I - - -
24. enable/disable developer modes - - - -
25. enable data-at rest protection - - - -
26. enable removable media’s data-at-rest protection - - - -
27. enable/disable bypass of local user authentication - - - -
28. wipe Enterprise data - - - -
29. approve [selection: import, removal] by applications of X.509v3 certificates in the
Trust Anchor Database
- - - -
30. configure whether to establish a trusted channel or disallow establishment if the TSF
cannot establish a connection to determine the validity of a certificate
- - - -
31. enable/disable the cellular protocols used to connect to cellular network base stations - - - -
32. read audit logs kept by the TSF - - - -
33. configure [selection: certificate, public-key] used to validate digital signature on
applications
- - - -
34. approve exceptions for shared use of keys/secrets by multiple applications - - - -
35. approve exceptions for destruction of keys/secrets by applications that did not import
the key/secret
- - - -
36. configure the unlock banner I - - -
37. configure the auditable items - - - -
38. retrieve TSF-software integrity verification values - - - -
39. enable/disable [selection:
a. USB mass storage mode,
b. USB data transfer without user authentication,
c. USB data transfer without authentication of the connecting system]
- - - -
40. enable/disable backup to [selection: locally connected system, remote system] - - - -
41. enable/disable [selection:
a. Hotspot functionality authenticated by [selection: pre-shared key, passcode, no
authentication],
b. USB tethering authenticated by [selection: pre-shared key, passcode, no
authentication]]
- - - -
42. approve exceptions for sharing data between [selection: application processes, groups
of application processes]
- - - -
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43. place applications into application process groups based on [assignment: application
characteristics]
- - - -
44. enable/disable location services:
a. across device
b. [no other method]
M - - -
45. [assignment: list of other management functions to be provided by the TSF] - - - -
5.1.4.3 Extended: Specification of Remediation Actions (FMT_SMF_EXT.2)
FMT_SMF_EXT.2.1
The TSF shall offer [alert the administrator and performs a factory reset of the device] upon
unenrollment and [no other triggers].
5.1.5 Protection of the TSF (FPT)
5.1.5.1 Extended: Anti-Exploitation Services (ASLR) (FPT_AEX_EXT.1)
FPT_AEX_EXT.1.1
The TSF shall provide address space layout randomization (ASLR) to applications.
FPT_AEX_EXT.1.2
The base address of any user-space memory mapping will consist of at least 8 unpredictable bits.
5.1.5.2 Extended: Anti-Exploitation Services (Memory Page Permissions) (FPT_AEX_EXT.2)
FPT_AEX_EXT.2.1
The TSF shall be able to enforce read, write, and execute permissions on every page of physical
memory.
5.1.5.3 Extended: Anti-Exploitation Services (Overflow Protection) (FPT_AEX_EXT.3)
FPT_AEX_EXT.3.1
TSF processes that execute in a non-privileged execution domain on the application processor
shall implement stack-based buffer overflow protection.
5.1.5.4 Extended: Domain Isolation (FPT_AEX_EXT.4)
FPT_AEX_EXT.4.1
The TSF shall protect itself from modification by untrusted subjects.
FPT_AEX_EXT.4.2
The TSF shall enforce isolation of address space between applications.
5.1.5.5 Application Processor Mediation (FPT_BBD_EXT.1)
FPT_BBD_EXT.1.1
The TSF shall prevent code executing on any baseband processor (BP) from accessing application
processor (AP) resources except when mediated by the AP.
5.1.5.6 Extended: Key Storage (FPT_KST_EXT.1)
FPT_KST_EXT.1.1
The TSF shall not store any plaintext key material in readable non-volatile memory.
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5.1.5.7 Extended: No Key Transmission (FPT_KST_EXT.2)
FPT_KST_EXT.2.1
The TSF shall not transmit any plaintext key material outside the security boundary of the TOE.
5.1.5.8 Extended: No Plaintext Key Export (FPT_KST_EXT.3)
FPT_KST_EXT.3.1
The TSF shall ensure it is not possible for the TOE user(s) to export plaintext keys.
5.1.5.9 Extended: Self-Test Notification (FPT_NOT_EXT.1)
FPT_NOT_EXT.1.1
The TSF shall transition to non-operational mode and [no other actions] when the following types
of failures occur:
 failures of the self-test(s)
 TSF software integrity verification failures
 [no other failures].
5.1.5.10 Reliable time stamps (FPT_STM.1)
FPT_STM.1.1
The TSF shall be able to provide reliable time stamps for its own use.
5.1.5.11 Extended: TSF Cryptographic Functionality Testing (FPT_TST_EXT.1)
FPT_TST_EXT.1.1
The TSF shall run a suite of self-tests during initial start-up (on power on) to demonstrate the
correct operation of all cryptographic functionality.
5.1.5.12 Extended: TSF Integrity Testing (FPT_TST_EXT.2)
FPT_TST_EXT.2.1
The TSF shall verify the integrity of the bootchain up through the Application Processor OS
kernel, and [all executable code stored in mutable media], stored in mutable media prior to its
execution through the use of [a digital signature using a hardware-protected asymmetric key].
5.1.5.13 Extended: Trusted Update: TSF version query (FPT_TUD_EXT.1)
FPT_TUD_EXT.1.1
The TSF shall provide authorized users the ability to query the current version of the TOE
firmware/software.
FPT_TUD_EXT.1.2
The TSF shall provide authorized users the ability to query the current version of the hardware
model of the device.
FPT_TUD_EXT.1.3
The TSF shall provide authorized users the ability to query the current version of installed mobile
applications.
5.1.5.14 Extended: Trusted Update Verification (FPT_TUD_EXT.2)
FPT_TUD_EXT.2.1
The TSF shall verify software updates to the Application Processor system software and
[[Baseband processor]] using a digital signature by the manufacturer prior to installing those
updates.
FPT_TUD_EXT.2.2
The TSF shall [update only by verified software] the TSF boot integrity [key].
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FPT_TUD_EXT.2.3
The TSF shall verify that the digital signature verification key used for TSF updates [matches a
hardware-protected public key].
FPT_TUD_EXT.2.4
The TSF shall verify mobile application software using a digital signature mechanism prior to
installation.
5.1.6 TOE access (FTA)
5.1.6.1 Extended: TSF- and User-initiated locked state (FTA_SSL_EXT.1)
FTA_SSL_EXT.1.1
The TSF shall transition to a locked state after a time interval of inactivity.
FTA_SSL_EXT.1.2
The TSF shall transition to a locked state after initiation by either the user or the administrator.
FTA_SSL_EXT.1.3
The TSF shall, upon transitioning to the locked state, perform the following operations:
a) clearing or overwriting display devices, obscuring the previous contents;
b) [no other actions].
5.1.6.2 Default TOE Access Banners (FTA_TAB.1)
FTA_TAB.1.1
Before establishing a user session, the TSF shall display an advisory warning message regarding
unauthorized use of the TOE.
5.1.6.3 Extended: Wireless Network Access (FTA_WSE_EXT.1)
FTA_WSE_EXT.1.1
The TSF shall be able to attempt connections to wireless networks specified as acceptable
networks as configured by the administrator in FMT_SMF_EXT.1.
5.1.7 Trusted path/channels (FTP)
5.1.7.1 Extended: Trusted channel Communication (FTP_ITC_EXT.1)
FTP_ITC_EXT.1.1
The TSF shall use 802.11-2012, 802.1X, and EAP-TLS and [TLS, HTTPS protocol] to provide a
communication channel between itself and another trusted IT product that is logically distinct
from other communication channels, provides assured identification of its end points, protects
channel data from disclosure, and detects modification of the channel data.
FTP_ITC_EXT.1.2
The TSF shall permit the TSF to initiate communication via the trusted channel.
FTP_ITC_EXT.1.3
The TSF shall initiate communication via the trusted channel for wireless access point
connections, administrative communication, configured enterprise connections, and [no other
connections].
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.
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Table 5-3 Assurance Components
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
ALC_TSU_EXT.1: Timely Security Updates
ATE: Tests ATE_IND.1: Independent testing - conformance
AVA: Vulnerability assessment AVA_VAN.1: Vulnerability survey
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
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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
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.
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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.
5.2.3.3 Timely Security Updates (ALC_TSU_EXT.1)
ALC_TSU_EXT.1.1d
The developer shall provide a description in the TSS of how timely security updates are made to
the TOE.
ALC_TSU_EXT.1.1c
The description shall include the process for creating and deploying security updates for the TOE
software/firmware.
ALC_TSU_EXT.1.2c
The description shall express the time window as the length of time, in days, between public
disclosure of a vulnerability and the public availability of security updates to the TOE.
ALC_TSU_EXT.1.3c
The description shall include the mechanisms publicly available for reporting security issues
pertaining to the TOE.
ALC_TSU_EXT.1.1e
The evaluator shall confirm that the information provided meets all requirements for content and
presentation of evidence.
5.2.4 Tests (ATE)
5.2.4.1 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.
5.2.5 Vulnerability assessment (AVA)
5.2.5.1 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.
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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
 Identification and authentication
 Security management
 Protection of the TSF
 TOE access
 Trusted path/channels
6.1 Cryptographic support
The TOE includes cryptographic libraries in each of three OKL4 cells. Each provides cryptographic functions in
support of various security features offered by the given cell. The TOE implements cryptographic algorithms in
accordance with the following NIST standards and has received CAVP algorithm certificates as shown in the
following table.
The TOE includes the OpenSSL library version 1.0.2j, using FIPS OpenSSL version 2.0.14, running as different
instances in the Block Cell OKL4 cell, and the Android OKL4 cell.
Table 6-1 Cryptographic Providers and CAVP Certificates
Algorithm NIST Standard SFR Reference Provider Cert#
AES
128/256 bit
CBC, CCM, and GCM modes
FIPS 197,
SP 800-38A/C/E
FCS_COP.1(1) OpenSSL AES: #4476
AES Key Wrap SP 800-38F
IEEE 802.11-2012
FCS_CKM.2(2) OpenSSL AES: #4476
SHS
SHA-1/256/384/512
FIPS 180-4 FCS_COP.1(2) OpenSSL SHA: #3686
RSA
SIG(gen), SIG(ver),
2048-bits
FIPS 186-4 FCS_CKM.2(1)
FCS_COP.1(3)
OpenSSL RSA: #2446
ECDSA
PKG, PKV, SigGen, SigVer, P-
256, P-384, P-521
FIPS 186-4 FCS_CKM.1(1)
FCS_CKM.2(1)
FCS_COP.1(3)
OpenSSL ECDSA: #1093
DSA
Sig(gen), SIG(ver), Key(GEN)
FIPS 186-4 FCS_CKM.1(1) OpenSSL DSA: #1200
HMAC SHA-1
HMAC SHA-256/384/512
FIPS 198-1 & 180-4 FCS_COP.1(4) OpenSSL HMAC: #2969
PBKDF2 NIST SP 800-132
No NIST CAVP test
available
FCS_COP.1(5) OpenSSL No Cert Possible
DRBG SP 800-90A FCS_RBG_EXT.1 OpenSSL DRBG: #1456
CVL
FCC
SP 800-56A FCS_CKM.2(1) OpenSSL CVL: #1191
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Algorithm NIST Standard SFR Reference Provider Cert#
ECC
The TOE derives all DEKs and KEKs as defined by the following table. The TOE uses a NIST 800-108 (CMAC)
key derivation function to derive keys used for the DAR functionality and the key store functionality which chain
from the Root Encryption Key (REK).
Table 6-2 D4 Secure CSP Information
Key Name Key
Type
Usage Algorithm /
Size
Generated From /
Derived from
ICE_RDK1
KEK Encrypt / decrypt
Intermediate value for
FDE_DKE
256-bit AES CBC Generated from SHK
using SP 800-108
(CMAC)
KeyMaster RDK KEK Encrypt / decrypt private
keys and symmetric keys
256-bit AES CBC Generated from SHK
using SP 800-108
(CMAC)
FDE_DEK DEK Encrypt / Decrypt user
data (FDE_DEK)
AES-128 XTS Generated using its
approved DRBG
WPA2 keys Ephemeral
session
key
Encrypt/decryption Wi-
Fi/802.11
communications
nonces Generated from OpenSSL
DRBG in Android Cell
TLS/HTTPS session
keys
Ephemeral
session
key
Encryption/decryption of
TLS/HTTPS sessions
128-bit / 256-bit
AES CBC
OpenSSL – Derived as
specified in TLS/HTTPS
protocol
Bluetooth BDR Ephemeral
session
key
Encryption/decryption of
Bluetooth
communications
128-bit AES Generated within
Bluetooth
The TOE provides an SP800-90A AES-256 CTR DRBG provided by FIPS OpenSSL library. Three instances of
this DRBG are present, one each in the various Linux / Android OKL4 cells requiring random data. User
applications can obtain random data from the AES-256 CTR_DRBG running in the Android OKL4 Cell.
The TOE initializes the RBG with sufficient entropy ultimately accumulated from a TOE-hardware-based noise
source (detailed information was provided to NIAP). The hardware based DRBG is seeded from the conditioned,
hardware noise source. The hardware-based DRBG is fed into the Linux kernels entropy pool which is reflected
through /dev/random. The FIPS OpenSSL library is seeded from /dev/random.
These sources for RBG all provide a security strength of at least 256-bits.
The Cryptographic support function is designed to satisfy the following security functional requirements:
 FCS_CKM.1(1): The TOE provides asymmetric key generation for DH, DHE/DSA and ECDH/ECDSA.
The TOE generates DH/ECDH, and ECDSA (including P-256, P384 and P-521) keys in its OpenSSL
software library (which generates the keys in accordance with FIPS 186-4). The TOE supports generating
keys with a security strength of 112-bits and larger, thus supports 2048-bit DH keys, and 256-bit ECDH
keys. The TOE utilizes generated DH/ECDH when acting as a TLS Client and the TOE provides mobile
applications HTTP/TLS APIs as well as general cryptographic APIs (to generate ECDSA key pairs).
1
RDK is a root derived key. The ICE_RDK is a key derived from the REK, and used to protect the ICE-based data-
at-rest protections.
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 FCS_CKM.1(2): The TOE adheres to 802.11-2012 for key generation. The TOE’s wpa_supplicant provides
the PRF384 for WPA2 derivation of 128-bit AES Temporal Key and also employs its OpenSSL AES-256
DRBG when generating random values use in the EAP-TLS and 802.11 4-way handshake. The TOE has
been designed for compliance, and the Device has successfully completed certification (including WPA2
Personal) and received a Wi-Fi CERTIFIED Interoperability Certificate from the Wi-Fi Alliance
(Certification ID: Cert # WFA61756). The Wi-Fi Alliance maintains a website providing further
information about the testing program: http://www.wi-fi.org/certification.
 FCS_CKM.2(1): The TOE supports RSA (800-56B), DHE (FFC 800-56A), and ECDHE (ECC 800-56A)
methods in TLS key establishment/exchange (the sole secure channel the TOE provides). The user and
administrator need take no special configuration of the TOE as the TOE automatically generates the keys
needed for negotiated TLS ciphersuite. Because the TOE only acts as a TLS client, the TOE only performs
800-56B encryption (specifically the encryption of the Pre-Master Secret using the Server’s RSA public
key) when participating in TLS_RSA_* based TLS handshakes. Thus, the TOE does not perform 800-56B
decryption during TLS handshakes. However, the TOE’s TLS client correctly handles other cryptographic
errors (for example, invalid checksums, incorrect certificate types, corrupted certificates) by sending a TLS
fatal alert.
 FCS_CKM.2(2): The TOE adheres to RFC 3394, SP 800-38F, and 802.11-2012 standards and unwraps the
GTK (sent encrypted with the WPA2 KEK using AES Key Wrap in an EAPOL-Key frame). The TOE,
upon receiving an EAPOL frame, will subject the frame to a number of checks (frame length, EAPOL
version, frame payload size, EAPOL-Key type, key data length, EAPOL-Key CCMP descriptor version,
and replay counter) to ensure a proper EAPOL message and then decrypt the GTK using the KEK, thus
ensuring that it does not expose the Group Temporal Key (GTK).
 FCS_CKM_EXT.1: The TOE includes a hardware-based, 256-bit Secondary Hardware Key (SHK) that is
provided by fuses on the processor. The SHK is Qualcomm terminology. Common Criteria requirements
refer to this as a Root Encryption Key (REK). The fuses making up the SHK are written once when the
device is first initialized using data from the hardware DRBG provided by the processor. The REK is used
to derive keys (w/ SP 800-108 CMAC) for Data-At-Rest (DAR) protection, AuthToken HMAC validation
and the KeyMaster keystore. The REK is never entered, read, exported, or updated after it is initialized.
The only operations allowed by or performed on the REK is key derivation using SP 800-108 (CMAC).
 FCS_CKM_EXT.2: The TOE generates all DEKs as described by Table 6-2 D4 Secure CSP Information.
 FCS_CKM_EXT.3: The TOE derives all DEKs and KEKs as defined by Table 6-2 D4 Secure CSP
Information.
 FCS_CKM_EXT.4: The TOE destroys cryptographic material (plaintext keys, authentication data, other
security parameters) when they are no longer in use by the system. No plaintext cryptographic keying
material resides in the TOE’s flash, because the TOE encrypts all keys stored in flash. When performing a
full wipe of protected data, the TOE cryptographically erases the protected data by clearing the FDE_DEK
that is used to encrypt the user data partition. Because the TOE’s keystore stores encrypted keys within the
user data partition, TOE effectively cryptographically erases those keys when clearing the Data-At-Rest
DEK (FDE_DEK). In turn, the TOE clears the FDE_DEK FEKs through a secure direct overwrite
(BLKSECDISCARD ioctl) of the Flash memory containing the key followed by a read-verify. The TOE
uses Flash memory with wear-leveling.
 FCS_CKM_EXT.5: The TOE stores all protected data in encrypted form within the user data partition.
Upon request, the TOE cryptographically erases the FDE_DEK that is protecting the user data partition,
clears that key from memory, reformats the partition, and then reboots. The TOE’s clearing of the
FDE_DEK follows the requirements of FCS_CKM_EXT.4.
 FCS_CKM_EXT.6: All salt value used by Android or Linux OKL4 cells are generated from an OpenSSL
DRBG.
 FCS_COP.1(1): The TOE uses multiple cryptographic providers to perform encryption and decryption
using AES in accordance with the standards, key sizes and modes referenced in Table 6-1 Cryptographic
Providers and CAVP Certificates.
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 FCS_COP.1(2): The TOE uses multiple cryptographic providers to perform cryptographic hashing using
SHA algorithms in accordance with the standards and message digest sizes referenced in Table 6-1
Cryptographic Providers and CAVP Certificates.
 FCS_COP.1(3): The TOE uses multiple cryptographic providers to perform cryptographic signature
generation and verification using either an ECDSA or RSA scheme that is in accordance with standards and
key-sizes referenced in Table 6-1 Cryptographic Providers and CAVP Certificates.
 FCS_COP.1(4): The TOE uses multiple cryptographic providers to perform keyed-hash message
authentication using the HMAC-SHA-1, HMAC-SHA-256, HMAC-SHA-384 and HMAC-SHA-512
algorithms, meeting the standards referenced in the tables above. These include key sizes and message
digest sizes of 160, 256, 384 and 512. Refer to Table 6-1 for associated CAVP certificate for these
algorithms.
 FCS_COP.1(5): The TOE conditions a user’s password per SP 800-132 using PBKDF2 using HMAC-
SHA-256 with 10000 iterations, to combine a 128-bit salt with the user’s password to obtain a 256-bit
master key which is provided to the Qualcomm Integrated Cryptographic Engine (ICE) for use by the full
disk encryption capability. The TOE utilizes several mechanism to increase the computational complexity
of the protections afforded by keys derived from passwords. First, the TOE performs 10000 HMAC-SHA-
256 iterations during PBKDF2 key derivation. The TOE also combines the password derived key with a
KEK chained to the REK. Finally, the TOE enforces a maximum number of incorrect login attempts prior
to wiping all user data.
The time needed to derive keying material does not impact or lessen the difficulty faced by an attacker’s
exhaustive guessing matter as the combination of the password derived KEK with REK value entirely
prevents offline attacks. The TOE’s maximum incorrect login attempts (less than 99), password length
(between 4 and 16 characters) and password complexity rules prevent exhaustive online attacks because the
number of combinations of passwords that an adversary can attempt is much higher than the maximum
incorrect login attempts required before a device wipe is triggered.
 FCS_HTTPS_EXT.1: The TOE supports the HTTPS protocol compliant with RFC 2818. Applications on
the TOE can act as an HTTPS client to connect to external servers using HTTPS over TLS (which is
compliant with FCS_TLSC_EXT.2). The TOE also offers TLS APIs that ensure the certificate checking
performed by the TOE as part of an HTTPS client's communications will satisfy FIA_X509_EXT not
establish the connection to the targeted server.
 FCS_IV_EXT.1: The TOE generates IVs for data storage encryption and for key storage encryption. The
TOE uses AES-CBC mode for data encryption.
 FCS_RBG_EXT.1: The TOE provides the DRBGs identified above having the CAVP certificates shown in
Table 6-1 Cryptographic Algorithms, Providers and CAVP certificates. The TOE initializes each RBG
with sufficient entropy ultimately accumulated from a TOE-hardware-based noise source (detailed
information was provided to NIAP). Once initialized the DRBGs provide a security strength of 256-bits.
 FCS_SRV_EXT.1: The TOE provides applications access to the cryptographic operations including
encryption (AES-CBC), hashing (SHA), signing and verification (RSA), key hashing (HMAC), password-
based key-derivation functions (PKBDFv2 HMAC-SHA-256), generation of asymmetric keys for key
establishment (RSA, DH, and ECDH), and generation of asymmetric keys for signature generation and
verification (RSA). The TOE provides access through the Android operating system’s Java API, through
the native OpenSSL API, and through the kernel.
 FCS_STG_EXT.1: The TOE provides the Android Key Store that is used by the Android Cell, and is
accessible to Android applications. The Android key stores is a hardware isolated protected keystores.
The Android Key Store is provided to the user and mobile applications. This keystore can generate, import
and securely store symmetric and asymmetric keys. Keys can also be destroyed. While normally mobile
applications cannot use or destroy the keys of another application, applications that share a common
application developer (and are thus signed by the same developer key) may do so. In other words
applications with a common developer may use and destroy each other’s keys located within the Secure
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Key Storage. The TOE utilizes a TrustZone implementation of KeyMaster key storage service to provide
hardware-isolated secure key storage, for symmetric keys and asymmetric private keys.
 FCS_STG_EXT.2: The REK derived keys used in the key hierarchy for Outer DAR protections and
Android's KeyMaster are never stored in non-volatile memory.
The Outer DAR DEK (a.k.a., FDE_DEK) is stored in non-volatile memory only when it is protected by a
KEK derived from the REK and by the user's password. Before being stored the FDE_DEK is encrypted
by a KEK derived from the user’s password using AES-256 in GCM mode, and the result is encrypted by a
KEK derived from the REK using AES-256 in GCM mode. The encrypted key and IV is then stored in the
crypto footer of the partition.
The Keymaster_RDK is used to provide an integrity hash of asymmetric private keys and symmetric keys
belonging to the user through the use of HMAC-SHA-256. These keys are protected by encrypting them
with the SHK using AES-256-CBC.
Wi-fi keys are protected through the use of 802.11-2012 Key Confirmation Key (KCK) and Key
Encryption Key (KEK) keys. These keys unwrap the WPA2 GTK (Group Temporal Key) send by an
access point. Persistent wi-fi keys such as pre-shared keys or certificates are protected by storing them on
an encrypted user data partition which is protected by a KEK chained to both a user’s password and the
device REK.
 FCS_STG_EXT.3: The integrity of the FDE_DEK is provided through the use of AES-256 in GCM mode
when the key is encrypted and decrypted. Stored asymmetric private keys and symmetric keys have
integrity protections through the use of HMAC-SHA-256 (using the KeyMaster RDK).
 FCS_TLSC_EXT.1: The TSF supports TLSv1.1, and TLSv1.0 using the following pre-configured
ciphersuites. These are used with EAP-TLS as part of WPA2.
- TLS_RSA_WITH_AES_128_CBC_SHA as defined in RFC 5246
- TLS_RSA_WITH_AES_256_CBC_SHA as defined in RFC 5246,
- TLS_DHE_RSA_WITH_AES_128_CBC_SHA as defined in RFC 5246,
- TLS_DHE_RSA_WITH_AES_256_CBC_SHA as defined in RFC 5246,
- TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA as defined in RFC 4492,
- TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA as defined in RFC 4492,
- TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA as defined in RFC 4492,
- TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA as defined in RFC 4492,
- TLS_RSA_WITH_AES_128_CBC_SHA256 as defined in RFC 5246,
- TLS_RSA_WITH_AES_256_CBC_ SHA256 as defined in RFC 5246,
- TLS_DHE_RSA_WITH_AES_128_CBC_ SHA256 as defined in RFC 5246,
- TLS_DHE_RSA_WITH_AES_256_CBC_ SHA256 as defined in RFC 5246,
- TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 as defined in RFC 5289,
- TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 as defined in RFC 5289,
- TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 as defined in RFC 5289,
- TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 as defined in RFC 5289,
The TOE supports mutual authentication by providing a certificate in response to a server's certificate
request message received during TLS negotiation. The TOE verifies X.509v3 certificates as per
FIA_X509_EXT.1, FIA_X509_EXT.2 and FIA_X509_EXT.3. When a certificate presented by a server
during TLS negotiation is deemed invalid, the TOE rejects the TLS channel negotiation (i.e., no connection
is established). The TOE supports authentication using only elliptic curves P-256, P-384 and P-521 within
EAP/TLS negotiation (corresponding to secp256r1, secp384r1, and secp521r1).
 FCS_TLSC_EXT.2: The TOE provides mobile applications (through its Android API) the use of TLS
versions 1.2 including support for the following pre-configured cipher suites.
- TLS_RSA_WITH_AES_128_CBC_SHA as defined in RFC 5246
- TLS_RSA_WITH_AES_256_CBC_SHA as defined in RFC 5246,
- TLS_DHE_RSA_WITH_AES_128_CBC_SHA as defined in RFC 5246,
- TLS_DHE_RSA_WITH_AES_256_CBC_SHA as defined in RFC 5246,
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- TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA as defined in RFC 4492,
- TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA as defined in RFC 4492,
- TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA as defined in RFC 4492,
- TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA as defined in RFC 4492,
- TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 as defined in RFC 5289,
- TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 as defined in RFC 5289,
The TOE supports mutual authentication by providing a X.509v3 certificate in response to a server's
certificate request message received during TLS negotiation. The TOE verifies X.509v3 certificates as per
FIA_X509_EXT.1, FIA_X509_EXT.2 and FIA_X509_EXT.3. In addition to this verification, the TOE
implements identity verification that is consistent with RFC 6125. This includes checks of the Subject
Alternative Name fields, checks of the Common Name field, and check for acceptable use of wildcards in
names. When a certificate presented by a server during TLS negotiation is deemed invalid, the TOE rejects
the TLS channel negotiation (i.e., no connection is established). The TOE supports authentication using
only elliptic curves P-256, P-384 and P-521 within TLS negotiation (corresponding to secp256r1,
secp384r1, and secp521r1).
6.2 User data protection
The TOE provides the following categories of system services to applications.
1. normal - A lower-risk permission that gives an application access to isolated application-level features,
with minimal risk to other applications, the system, or the user. The system automatically grants this type
of permission to a requesting application at installation, without asking for the user's explicit approval
(though the user always has the option to review these permissions before installing).
2. dangerous - A higher-risk permission that would give a requesting application access to private user data or
control over the device that can negatively impact the user. Because this type of permission introduces
potential risk, the system may not automatically grant it to the requesting application. For example, any
dangerous permissions requested by an application may be displayed to the user and require confirmation
before proceeding, or some other approach may be taken to avoid the user automatically allowing the use
of such facilities.
3. signature - A permission that the system is to grant only if the requesting application is signed with the
same certificate as the application that declared the permission. If the certificates match, the system
automatically grants the permission without notifying the user or asking for the user's explicit approval.
4. signatureOrSystem - A permission that the system is to grant only to packages in the Android system image
or that are signed with the same certificates. This permission is used for certain special situations where
multiple vendors have applications built in to a system image which need to share specific features
explicitly because they are being built together.
An example of a normal permission is the ability to vibrate the device: android.permission.VIBRATE. This
permission allows an application to make the device vibrate, and an application that does not declare this permission
would have its vibration requests ignored.
An example of a dangerous privilege would be access to location services to determine the location of the mobile
device: android.permission.ACCESS_FINE_LOCATION. The TOE controls access to Dangerous permissions
during the installation of the application. The TOE prompts the user to review the application's requested
permissions (by displaying a description of each permission group, into which individual permissions map, that an
application requested access to). If the user approves, then the mobile device continues with the installation of the
application. Thereafter, the mobile device grants that application during execution access to the set of permissions
declared in its Manifest file.
An example of a signature permission is the android.permission.BIND_VPN_SERVICE, that an application must
declare in order to utilize the VpnService APIs of the device. Because the permission is a Signature permission, the
mobile device only grants this permission to an application that requests this permission and that has been signed
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with the same developer key used to sign the application declaring the permission (in the case of the example, the
Android Framework itself).
An example of a systemOrSignature permission is the android.permission.LOCATION_HARDWARE, which
allows an application to use location features in hardware (such as the geofencing API). The device grants this
permission to requesting applications that either have been signed with the same developer key used to sign the
android application declaring the permissions or that reside in the 'system directory within Android, which for
Android 4.4 and above, are applications residing in the /system/priv-app/ directory on the read-only system
partition). Put another way, the device grants systemOrSignature permissions by Signature or by virtue of the
requesting application being part of the 'system image.'
Additionally, Android includes the following flags that layer atop the base categories.
a) privileged and signature- The privileged permission is granted to any applications installed as a privileged
app on the system image. The signature protection level is sufficient for most needs and works regardless
of exactly where applications are installed. These permission flags are used for certain special situations
where multiple vendors have applications built in to a system image which need to share specific features
explicitly because they are being built together.
b) system - Old synonym for 'privileged'.
c) development - this permission can also (optionally) be granted to development applications (e.g., to allow
additional location reporting during beta testing).
d) appop - this permission is closely associated with an app op for controlling access.
e) pre23 - this permission can be automatically granted to apps that target API levels below API level 23
(Marshmallow/6.0).
f) installer - this permission can be automatically granted to system apps that install packages.
g) verifier- this permission can be automatically granted to system apps that verify packages.
h) preinstalled - this permission can be automatically granted any application pre-installed on the system
image (not just privileged apps) (the TOE does not prompt the user to approve the permission).
Refer to Table 6-3 Categories of System Services for specific permissions associated with protection levels
applicable to the TOE.
Table 6-3 Categories of System Services
Permission
Table.docx
The User data protection function is designed to satisfy the following security functional requirements:
 FDP_ACF_EXT.1: The mechanism to restrict system services that are accessible to an application are
shown in the text immediately above.
 FDP_DAR_EXT.1: The TOE utilizes the Qualcomm Integrated Cryptographic Engine (ICE) to provide
AES-128 XTS mode encryption for all data stored on the TOE in the user data partition (which includes
both user data and TSF data). The TOE also has TSF data relating to key storage for TSF keys not stored in
the system's Android Key Store. The TOE separately encrypts those TSF keys and data. Additionally, the
TOE includes a read-only file system in which the TOE's system executables, libraries, and their
configuration data reside. For its Data-At-Rest encryption of the user data partition on the internal Flash
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(where the TOE stores all user data and all application data), the TOE uses the AES-128 bit DEK in XTS
mode to encrypt the entire partition. The SD Card reader is not accessible to the Android cell.
 FDP_IFC_EXT.1: The D4 Secure provides a 3rd
party VPN client within the Android cell with an API to
ensure IP routes are configured to direct IP traffic through a 3rd
party VPN client. The API ensures that all
traffic is directed through the VPN client when a VPN client connection exists. The API configures kernel
packet filtering rules to ensure the TOE transmits all outbound traffic through the VPN Client and the TOE
accepts inbound traffic only if that traffic is part of the established VPN connection. All traffic that is not
part of the VPN connection is discarded by the TOE.
 FDP_STG_EXT.1: The TOE's Android Cell provides a Trusted Anchor Database that consists of built-in
certificates and any additional user or admin/MDM loaded certificates. The built-in certs along with user
added certs are stored in user specific directories within the user data partition. Neither the Block Cell,
OKL4 hypervisor nor QSEE Trustzone access certificates in the Trust Anchor Database.
 FDP_UPC_EXT.1: The TOE provides APIs allowing non-TSF applications (mobile applications) the
ability to establish a secure channel using TLS, HTTPS, Bluetooth DR/EDR and Bluetooth BR/EDR.
Mobile applications can use the following Android APIs for TLS, HTTPS, and Bluetooth respectively:
javax.net.ssl.SSLContext:
http://developer.android.com/reference/javax/net/ssl/sslcontext.html
javax.net.ssl.httpsurlconnection:
http://developer.android.com/reference/javax/net/ssl/httpsurlconnection.html
android.bluetooth:
http://developer.android.com/reference/android/bluetooth/package-summary.html
6.3 Identification and authentication
The Identification and authentication function is designed to satisfy the following security functional requirements:
 FIA_AFL_EXT.1: The TOE maintains, for each user, the number of failed logins since the last successful
login, and upon reaching the maximum number of incorrect logins, the TOE performs a full wipe of all
protected data (and in fact, wipes all user data). An administrator can adjust the number of failed logins
from the default of ten failed logins to a value between one and one hundred using an MDM. Turning
power to the device off, does not affect the count of failed logins maintained by the TOE, because this
count is saved in non-volatile storage. The lock screen failure count is maintained through a successful
DAR authentication.
 FIA_BLT_EXT.1: The TOE requires explicit user authorization before it will pair with a remote Bluetooth
device. The user can make the TOE visible to other Bluetooth enabled devices and can attempt, via explicit
user action, to pair with a visible device. Furthermore, the user must explicitly accept pairing attempts from
other devices.
 FIA_PAE_EXT.1: The TOE can join WPA2-802.1X (802.11i) wireless networks requiring EAP-TLS
authentication, acting as a client/supplicant (and in that role connect to the 802.11 access point and
communicate with the 802.1X authentication server).
 FIA_PMG_EXT.1: The TOE allows password for accounts to be composed of upper or lower case letters,
numbers, and special characters including !, @, #, $, %, ^, &, *, (, ), +, =, _, /, -, ', ", :, ;, comma, ?, `, ~, \, |,
<, >, {, }, [, and ]. The TOE defaults to requiring passwords to have a minimum of four characters but no
more than sixteen. However, an MDM application can change these defaults.
 FIA_TRT_EXT.1: The TOE allows users to authenticate at the touchscreen. A user must authenticate
through the standard User Interface (using the TOE touchscreen). The TOE limits the number of
authentication attempts through the UI to no more than ten attempts within 30 seconds. Thus if the current
[the nth] and prior nine authentication attempts have failed, and the n-9th attempt was less than 30 second
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ago, the TOE will prevent any further authentication attempts until 30 seconds has elapsed. Note as well
that the TOE will wipe itself when it reaches the maximum number of unsuccessful authentication attempts
(as described in FIA_AFL_EXT.1 above).
 FIA_UAU.7: The TOE allows the user to enter the user's password from the lock screen or from the DAR
lock screen. The TOE will, by default, display the most recently entered character of the password briefly
or until the user enters the next character in the password, at which point the TOE obscures the character by
replacing the character with a dot symbol.
 FIA_UAU_EXT.1: The TOE requires that a user enter their password in order for the TOE to derive a
master key that can be combined with a KEK chaining to the REK; thus allowing the TOE to decrypt the
DEK that protects the data stored in the user data partition (including the long-term trusted channel key
material which is stored in the user data partition).
 FIA_UAU_EXT.2: The TOE, when configured to require a user password, the TOE will allow a user to do
the following things before successfully authenticating:
 make an emergency call,
 receive an incoming phone calls,
 take screen shots (automatically named and stored internally by the TOE),
 turn the TOE off,
 enable or disable airplane mode,
 configure sound/vibrate/mute,
 use a flashlight,
 use a calculator app,
 use a voice recorder app, and
 change notification display level.
Beyond those actions, a user cannot perform any other actions other than observing notifications displayed
on the lock screen until after successfully authenticating. The TOE allows a user to configure, on a per
application basis, whether notifications will be displayed.
 FIA_UAU_EXT.3: The TOE requires the user to enter their password in order to unlock the TOE.
Additionally the TOE requires the user to confirm their current password when accessing the 'Settings-
>Screen Lock' menu in the TOE's user interface. Only after entering their current user password can the
user then elect to change their password.
 FIA_X509_EXT.1: The TOE checks the validity of all imported CA certificates by checking for the
presence of the basicConstraints extension and that the CA flag is set to TRUE. These checks occur as the
TOE imports the certificate (per RFC 5280). Additionally the TOE verifies the extendedKeyUsage Server
Authentication purpose during WPA2/EAP-TLS negotiation. The TOE's certificate validation algorithm
examines each certificate in the path (starting with the peer's certificate) and first checks for validity of that
certificate (e.g., has the certificate expired or it not yet valid, whether the certificate contains the
appropriate X.509 extensions such as the CA flag in the basic constraints extension for a CA certificate, or
that a server certificate contains the Server Authentication purpose in the ExtendedKeyUsagefield), then
verifies each certificate in the chain (applying the same rules as above, but also ensuring that the Issuer of
each certificate matches the Subject in the next rung 'up' in the chain and that the chain ends in a self-signed
certificate present in either the TOE's trusted anchor database or matches a specified Root CA), and finally
the TOE performs revocation checking for all certificates in the chain using a Certificate Revocation List
(per RFC 5759).
 FIA_X509_EXT.2: The TOE uses X.509v3 certificates as part of protocol processing for EAP-TLS, TLS
and HTTPS. The TOE comes with a built-in set of trusted certificates (a Trust Anchor Database). Users
cannot remove any of these built-in CA certificates, but can make any as 'disabled' (which prevents them
from being used to validate another certificate). Users and administrators can also import new trusted CA
certificates into the Trust Anchor Database.
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If, during the process of certificate verification, the TOE cannot establish a connection with the server
acting as the CRL Distribution Point (CDP), the TOE EAP-TLS implementation accepts the certificate.
Also, the TOE TLS and HTTPS implementations reject the certificate when the revocation server cannot be
reached.FIA_X509_EXT.3: The TOE's Android operating system provides applications with several Java
API Class of methods for validating certification paths (certificate chains) that establishing a trust chain
from a certificate to a trust anchor.
6.4 Security management
The Security management function is designed to satisfy the following security functional requirements:
 FMT_MOF_EXT.1: The TOE provides the management functions as described in Table 5-2 Security
Management Functions. The table includes annotations describing the roles that have access to each service
and how to access the service.
 FMT_SMF_EXT.1: The TOE provides all management functions indicated as mandatory ('M') or
implemented ('I') by Table 5-2 Security Management Functions.
 FMT_SMF_EXT.2: The TOE when unenrolled from an MDM alerts the administrator of the unenrollment
and performs a factory reset.
6.5 Protection of the TSF
The Protection of the TSF function is designed to satisfy the following security functional requirements:
 FPT_AEX_EXT.1: The Linux kernel of the TOE's Linux Cells and Android Cell utilize address space
layout randomization utilizing the get_random_int(void) kernel random function to provide eight
unpredictable bits to the base address of any user-space memory mapping. The random function, though
not cryptographic, ensures that one cannot predict the value of the bits.
 FPT_AEX_EXT.2: The TOE's OKL4 hypervisor performs memory management that enforces read, write,
and execute permissions on all pages of physical and virtual memory. The TOE's Android 6.0.1 operating
system utilizes a 3.10.x Linux kernel, whose memory management unit (MMU) enforces read, write, and
execute permissions on all pages of virtual memory within its control. The Android operating system (as of
Android 2.3) sets the ARM No eXecute (XN) bit on memory pages and the TOE's ARMv8 Application
Processor's Memory Management Unit (MMU) circuitry enforces the XN bits. From Android's
documentation (https://source.android.com/devices/tech/security/index.html), Android 2.3 forward supports
'Hardware-based No eXecute (NX) to prevent code execution on the stack and heap'.
 FPT_AEX_EXT.3: The TOE's OKL4 Hypervisor and Android operating system provides explicit
mechanisms to prevent stack buffer overruns in addition to taking advantage of hardware-based No
eXecute to prevent code execution on the stack and heap. Specifically, the vendor builds the TOE (Android
and support libraries) using -fstack-protector GCC feature. This compile option enables stack overflow
protection and Android takes advantage of ARM v8 eXecute-Never to make the stack and heap non-
executable. The vendor applies these protections to all TSF executable binaries and libraries (refer to 7,
TSF Inventory for a complete list).
 FPT_AEX_EXT.4: The TOE protects itself from modification by untrusted subjects using a variety of
methods. The first protection employed by the mobile device is a Secure Boot process that uses
cryptographic signatures to ensure the authenticity and integrity of the bootloader and kernels using data
fused into the device processor. The TOE protects its Device Key (REK) by generating and securely storing
the Device Key within hardware and making it accessible only to Android TrustZone software. The REK is
used to protect all other keys in the key hierarchy. The TOE ensures that all TrustZone software is
cryptographically signed and that the signature is verified when the TrustZone software is invoked.
Additionally, the TOE's Android operating system provides 'sandboxing' that ensures that each third-party
mobile application executes with the file permissions of a unique Linux User ID, in a different virtual
memory space. This ensures that applications cannot access each other's memory space or files and cannot
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access the memory space or files of other applications (notwithstanding access between applications with a
common application developer).
Finally, the TOE's OKL4 hypervisor separates functions for a VPN and Data-at-rest encryption from the
Android operating system, to ensure that the Outer DAR functio cannot be bypassed.
 FPT_BBD_EXT.1: The TOE’s hardware and software architecture ensures separation of the application
processor (AP) from the baseband through internal controls of the TOE’s SoC.
 FPT_KST_EXT.1: The TOE does not store any plaintext key material in its internal Flash. This ensures
that irrespective of how the TOE powers down (e.g., a user commands the TOE to power down, the TOE
reboots itself, or battery depletes or is removed), all keys in internal are wrapped with a KEK. Refer to
Section 6.1 for a description of the keys, the key hierarchy, and the key storage protections afforded to all
keys. The TOE encrypts all keys stored in Flash, upon boot-up, the TOE must first decrypt any keys in
order to utilize them.
 FPT_KST_EXT.2: The TOE itself (i.e., the mobile device) comprises a cryptographic module that utilizes
the OpenSSL cryptographic library running within Linux Cells (i.e., Android Cell, Block Cell) along with
system-level executables that utilize KEKs within the Android Cell: wpa_supplicant, Gatekeeper2
and
KeyMaster. The TOE ensures that plaintext key material does not leave this cryptographic module by only
allowing the system-level executables access to the plaintext KEK values that protect all other keys in the
TOE. The TSF software SD CAr(the system-level executables) protects the plaintext KEKs and any
plaintext DEK values in memory both by not providing any access to these values and by clearing them
when no longer needed (in compliance with FCS_CKM_EXT.4).
 FPT_KST_EXT.3: The TOE does not provide any way to export plaintext DEKs or KEKs (including all
keys stored in the Secure Key Store) as the TOE chains or directly encrypts all KEKs to the REK.
 FPT_NOT_EXT.1: When TOE self-tests detect a failure of self-test or TSF verification tests, the TOE
enters a non-operational mode. In this mode the TOE presents the page 'Decryption unsuccessful' with a
'Reset' button. Upon press of the Reset button the TOE will perform a factory reset of the device.
Alternately, a power cycle of the device will attempt a restart to boot again. Upon boot (either following a
power-cycle or a factory reset) the self-test and TSF verifications run again and can repeat the process if
failures continue.
 FPT_STM.1: The TOE requires accurate time values for certificate validation, wpa_supplicant, and key
store applications. These TOE components obtain time from the TOE using system API calls [e.g., time()
or gettimeofday()]. An application cannot modify the system time as mobile applications need the android
'SET_TIME' permission to do so. Likewise, only a process with root privileges can directly modify the
system time using system-level APIs. The TOE uses the Cellular Carrier time (obtained through the
Carrier's network time server) as a trusted source; however, the user can also manually set the time through
the TOE's user interface.
 FPT_TST_EXT.1: The TOE performs known answer power on self-tests (POST) on its cryptographic
algorithms to ensure that they are functioning correctly. The kernel itself performs known answer tests on
its cryptographic algorithms to ensure they are working correctly and the SecurityManager service invokes
the self-tests of OpenSSL at start-up to ensure that those cryptographic algorithms are working correctly.
Should any of the tests fail, the TOE will reboot to see if that will clear the error.
Table 6-4 Power-up Cryptographic Algorithm Known Answer Tests
Algorithm Implemented in Description
AES encryption/decryption OpenSSL Comparison of known answer to calculated valued
ECDH key agreement OpenSSL Comparison of known answer to calculated valued
DRBG random bit generation OpenSSL Comparison of known answer to calculated valued
HMAC-SHA OpenSSL Comparison of known answer to calculated valued
2
Gatekeeper is an Android subsystem that is part of the TOE. It runs in Trustzone and supports user authentication.
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SHA hashing OpenSSL Comparison of known answer to calculated valued
RSA OpenSSL Comparison of known answer to calculated valued
ECDSA OpenSSL Comparison of known answer to calculated valued
 FPT_TST_EXT.2: The TOE ensures a secure boot process in which the TOE verifies the digital signature
of the bootloader software for the Application Processor (using a public key whose hash resides in the
processor’s internal fuses) before transferring control. The bootloader, in turn, validates the signature of the
Cog Secure Boot partition using the same public key by which the bootloader was signed. The Cog Secure
Boot partition includes the Cog public key, which is used to sign the Hypervisor system. So the bootloader
validates and (if validation is successful) starts the Cog Secure Boot image, which validates and (if
validation is successful) starts the Hypervisor system. The Hypervisor System image contains the OKL4
Hypervisor along with the all other cells including the Android cell, Block Cell, Inner DAR Cell, Outer
DIT cell, HSM Proxy cell, and C2-Agent cell. The Hypervisor System starts these cells, however, some
cells can only initialize fully after other cells are operating (e.g., the Android cell and other cells must wait
until their filesystems are made available by Outer DAR functionality of the Block cell). The Android User
Data partition is available only after the partition has been successfully unlocked(decrypted).
 FPT_TUD_EXT.1: The TOE's user interface provides a method to query the current version of the TOE
software/firmware (including the hypervisor version, and kernel version) and hardware (model and
version). This information can be viewed through the command “Settings” -> “About” -> “Software
information” -> “More” -> “Kernel version”. Additionally, the TOE provides users the ability to review
the currently installed apps (including 3rd party built-in applications) and their version.
 FPT_TUD_EXT.2: The TOE supports “side-loading” an update from SD card. A firmware update occurs
if a new image is detected when the provisioning service detects a new image during the device boot
process. When a new image is detected and before the new image is installed, the HTC bootloader
validates the new Cog Secure Boot image in the same manner in which it validates an already installed boot
image. This ensures that the new image has been signed using the same public key by which the
bootloader was signed (i.e., a public key whose hash is burned into the device’s fuses). Once installed, an
update entirely replaces the Cog Secure Boot image, and the Hypervisor system image (which includes cell
images), then restarts the boot process. The normal boot process then re-validates every part of the boot
chain. The code that runs on the baseband processor is loaded as part of the Android image.
The Android OS on the TOE requires that all applications bear a valid signature before Android will install
the application.
6.6 TOE access
The TOE access function is designed to satisfy the following security functional requirements:
 FTA_SSL_EXT.1: The TOE can transition into a locked state either as a result of exceeding the configured
inactivity period, the user pressing the power button, or as a result of receiving a 'lock' command from an
MDM server through an authenticated and protected channel. Upon entering a locked state the TOE
obscures the previous content by displaying a lock screen. After being locked, the lock screen displays
email notifications, text message notifications, call notifications, date, time, battery life, signal strength and
carrier network. In order to act upon the notifications, the user must authenticate to the TOE.
Note that during power up, the TOE presents the user with an initial power-up Data-At-Rest lock screen,
where the user can only make an emergency call or enter the user password in order to allow the TOE to
decrypt the Data-At-Rest key (i.e., FDE_DEK) so as to be able to access the data partition and unlock the
screen. After successfully authenticating at the initial power-up Data-At-Rest login screen, the user can
access the TOE and upon (re)locking the TOE, the TOE will present the user the normal lock screen (which
displays and allows the actions described in FIA_UAU_EXT.2.1.
 FTA_TAB.1: The TOE can be configured to display a message on the login screen and on the lock screen
prior to user login.
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 FTA_WSE_EXT.1: The TOE allows an administrator to specify (through the use of an MDM) a list of
wireless networks (SSIDs) to which the user may direct the TOE to connect to. When not enrolled with an
MDM, the TOE allows the user to control to which wireless networks the TOE should connect, but does
not provide an explicit list of such networks, rather the use may scan for available wireless network (or
directly enter a specific wireless network), and then connect. Once a user has connected to a wireless
network, the TOE will automatically reconnect to that network when in range and the user has enabled the
TOE's Wi-Fi radio.
6.7 Trusted path/channels
The Trusted path/channels function is designed to satisfy the following security functional requirements:
 FTP_ITC_EXT.1: The TOE provides secured (encrypted and mutually authenticated) communication
channels between itself and other trusted IT products through the use of 802.11-2012, 802.1X, and EAP-
TLS, TLS, and HTTPS protocols. The TOE permits itself and applications to initiate communications via
the trusted channel, and the TOE initiates communicate via the trusted channel for connection to a wireless
access point. The TOE provides access to TLS via published APIs which are accessible to any application
that needs an encrypted end-to-end trusted channel.
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7. TSF Inventory
Below is a list of user-mode TSF binaries and libraries. All are built with the -fstack-protector option set. For each
binary/library, the name, path and security function is provided.
Name Path Securuty Function
dalvikvm system/bin Virtual Machine
dalvikvm32 system/bin Virtual Machine
dalvikvm64 system/bin Virtual Machine
keystore system/bin Keystore
time_daemon system/bin Time
qseecomd system/bin Trustone Daemon
qfipsverify system/bin Self tests
vold system/bin DAR
wpa_supplicant system/bin WPA2
libcrypto.so system/lib Crypto
libjavacrypto.so system/lib Crypto JNI
libkeystore_binder.so system/lib KeyStore
libssl.so system/lib SSL/TLS
libcrypto.so system/lib64 Crypto
libjavacrypto.so system/lib64 Crypto JNI
libkeystore_binder.so system/lib 64 KeyStore
libssl.so system/lib64 SSL/TLS