Pixel 3 and Pixel 3 XL
(MDFPP31/WLANCEP10) Security
Target
Version 0.6
2019/07/17
Prepared for:
Google LLC
1600 Amphitheatre Parkway
Mountain View, CA 94043
USA
Prepared By:
www.gossamersec.com
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1. Security Target Introduction..................................................................................................................................6
1.1 Security Target Reference............................................................................................................................6
1.2 TOE Reference..............................................................................................................................................6
1.3 TOE Overview...............................................................................................................................................7
1.4 TOE Description............................................................................................................................................7
1.4.1 TOE Architecture......................................................................................................................................8
1.4.1.1 Physical Boundaries ........................................................................................................................8
1.4.1.2 Logical Boundaries ..........................................................................................................................8
1.4.2 TOE Documentation...............................................................................................................................10
2. Conformance Claims............................................................................................................................................11
2.1 Conformance Rationale..............................................................................................................................11
3. Security Objectives ..............................................................................................................................................12
3.1 Security Objectives for the Operational Environment ...............................................................................12
4. Extended Components Definition .......................................................................................................................13
5. Security Requirements ........................................................................................................................................16
5.1 TOE Security Functional Requirements......................................................................................................16
5.1.1 Security audit (FAU)...............................................................................................................................19
5.1.1.1 Audit Data Generation (FAU_GEN.1) ...........................................................................................19
5.1.1.2 Audit Storage Protection (FAU_STG.1) ........................................................................................19
5.1.1.3 Prevention of Audit Data Loss (FAU_STG.4).................................................................................19
5.1.2 Cryptographic support (FCS)..................................................................................................................20
5.1.2.1 Cryptographic key generation (FCS_CKM.1) ................................................................................20
5.1.2.2 Cryptographic Key Generation (Symmetric Keys for WPA2 Connections) (FCS_CKM.1/WLAN)..20
5.1.2.3 Cryptographic key establishment (FCS_CKM.2(1)) ......................................................................20
5.1.2.4 Cryptographic key establishment (While device is locked) (FCS_CKM.2(2))................................20
5.1.2.5 Cryptographic Key Distribution (GTK) (FCS_CKM.2/WLAN) .........................................................20
5.1.2.6 Extended: Cryptographic Key Support (FCS_CKM_EXT.1)............................................................20
5.1.2.7 Extended: Cryptographic Key Random Generation (FCS_CKM_EXT.2)........................................21
5.1.2.8 Extended: Cryptographic Key Generation (FCS_CKM_EXT.3) ......................................................21
5.1.2.9 Extended: Key Destruction (FCS_CKM_EXT.4) .............................................................................21
5.1.2.10 Extended: TSF Wipe (FCS_CKM_EXT.5)........................................................................................22
5.1.2.11 Extended: Salt Generation (FCS_CKM_EXT.6)..............................................................................22
5.1.2.12 Cryptographic operation (FCS_COP.1(1)).....................................................................................22
5.1.2.13 Cryptographic operation (FCS_COP.1(2)).....................................................................................22
5.1.2.14 Cryptographic operation (FCS_COP.1(3)).....................................................................................22
5.1.2.15 Cryptographic operation (FCS_COP.1(4)).....................................................................................22
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5.1.2.16 Cryptographic operation (FCS_COP.1(5)).....................................................................................23
5.1.2.17 Extended: HTTPS Protocol (FCS_HTTPS_EXT.1) ...........................................................................23
5.1.2.18 Extended: Initialization Vector Generation (FCS_IV_EXT.1).........................................................23
5.1.2.19 Extended: Cryptographic Operation (Random Bit Generation) (FCS_RBG_EXT.1) ......................23
5.1.2.20 Extended: Cryptographic Algorithm Services (FCS_SRV_EXT.1) ..................................................23
5.1.2.21 Extended: Cryptographic Algorithm Services (FCS_SRV_EXT.2) ..................................................23
5.1.2.22 Extended: Cryptographic Key Storage (FCS_STG_EXT.1) .............................................................24
5.1.2.23 Extended: Encrypted Cryptographic Key Storage (FCS_STG_EXT.2) ............................................24
5.1.2.24 Extended: Integrity of encrypted key storage (FCS_STG_EXT.3) .................................................25
5.1.2.25 Extended: TLS Protocol (FCS_TLSC_EXT.1)...................................................................................25
5.1.2.26 Extended: TLS Protocol (FCS_TLSC_EXT.2)...................................................................................25
5.1.2.27 Extensible Authentication Protocol-Transport Layer Security (FCS_TLSC_EXT.1/WLAN)............25
5.1.2.28 TLS Client Protocol (FCS_TLSC_EXT.2/WLAN) ...............................................................................26
5.1.3 User data protection (FDP) ....................................................................................................................26
5.1.3.1 Extended: Security access control (FDP_ACF_EXT.1)...................................................................26
5.1.3.2 Extended: Security access control (FDP_ACF_EXT.2)...................................................................26
5.1.3.3 Extended: Protected Data Encryption (FDP_DAR_EXT.1) ............................................................27
5.1.3.4 Extended: Sensitive Data Encryption (FDP_DAR_EXT.2)..............................................................27
5.1.3.5 Extended: Subset information flow control (FDP_IFC_EXT.1)......................................................27
5.1.3.6 Extended: Storage of Critical Biometric Parameters.....................................................................27
5.1.3.7 Extended: User Data Storage (FDP_STG_EXT.1) ..........................................................................27
5.1.3.8 Extended: Inter-TSF user data transfer protection (FDP_UPC_EXT.1).........................................27
5.1.4 Identification and authentication (FIA)..................................................................................................28
5.1.4.1 Extended: Authentication failure handling (FIA_AFL_EXT.1).......................................................28
5.1.4.2 Extended: Bluetooth User Authorization (FIA_BLT_EXT.1)..........................................................28
5.1.4.3 Extended: Bluetooth Mutual Authentication (FIA_BLT_EXT.2)....................................................28
5.1.4.4 Extended: Rejection of Duplicate Bluetooth Connections (FIA_BLT_EXT.3)................................28
5.1.4.5 Extended: Secure Simple Pairing (FIA_BLT_EXT.4).......................................................................28
5.1.4.6 Extended: Bluetooth User Authorization (FIA_BLT_EXT.6)..........................................................29
5.1.4.7 Extended: Accuracy of Biometric Authentication (FIA_BMG_EXT.1)...........................................29
5.1.4.8 Port Access Entity Authentication (FIA_PAE_EXT.1) ....................................................................29
5.1.4.9 Extended: Password Management (FIA_PMG_EXT.1) .................................................................29
5.1.4.10 Extended: Authentication Throttling (FIA_TRT_EXT.1) ................................................................29
5.1.4.11 Multiple Authentication Mechanisms (FIA_UAU.5).....................................................................29
5.1.4.12 Re-Authentication (FIA_UAU.6(1))...............................................................................................30
5.1.4.13 Re-Authentication (FIA_UAU.6(2))...............................................................................................30
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5.1.4.14 Protected authentication feedback (FIA_UAU.7).........................................................................30
5.1.4.15 Extended: Authentication for Cryptographic Operation (FIA_UAU_EXT.1) .................................30
5.1.4.16 Extended: Timing of Authentication (FIA_UAU_EXT.2)................................................................30
5.1.4.17 Extended: Validation of certificates (FIA_X509_EXT.1)................................................................31
5.1.4.18 Extended: X509 certificate authentication (FIA_X509_EXT.2) .....................................................31
5.1.4.19 X.509 Certificate Authentication (EAP-TLS) (FIA_X509_EXT.2/WLAN).........................................31
5.1.4.20 Extended: Request Validation of certificates (FIA_X509_EXT.3)..................................................31
5.1.5 Security management (FMT) .................................................................................................................31
5.1.5.1 Extended: Management of security functions behavior (FMT_MOF_EXT.1)...............................31
5.1.5.2 Extended: Specification of Management Functions (FMT_SMF_EXT.1) ......................................32
5.1.5.3 Specification of Management Functions (Wireless LAN) (FMT_SMF_EXT.1/WLAN) ...................36
5.1.5.4 Extended: Specification of Remediation Actions (FMT_SMF_EXT.2)...........................................36
5.1.5.5 Extended: Current Administrator (FMT_SMF_EXT.3) ..................................................................37
5.1.6 Protection of the TSF (FPT) ....................................................................................................................37
5.1.6.1 Extended: Anti-Exploitation Services (ASLR) (FPT_AEX_EXT.1)....................................................37
5.1.6.2 Extended: Anti-Exploitation Services (Memory Page Permissions) (FPT_AEX_EXT.2).................37
5.1.6.3 Extended: Anti-Exploitation Services (Overflow Protection) (FPT_AEX_EXT.3)...........................37
5.1.6.4 Extended: Domain Isolation (FPT_AEX_EXT.4).............................................................................37
5.1.6.5 Extended: Anti-Exploitation Services (ASLR) (FPT_AEX_EXT.5)....................................................37
5.1.6.6 Extended: Application Processor Mediation (FPT_BBD_EXT.1) ...................................................37
5.1.6.7 Extended: JTAG Disablement (FPT_JTA_EXT.1)............................................................................37
5.1.6.8 Extended: Key Storage (FPT_KST_EXT.1) .....................................................................................38
5.1.6.9 Extended: No Key Transmission (FPT_KST_EXT.2) .......................................................................38
5.1.6.10 Extended: No Plaintext Key Export (FPT_KST_EXT.3)...................................................................38
5.1.6.11 Extended: Self-Test Notification (FPT_NOT_EXT.1) .....................................................................38
5.1.6.12 Reliable time stamps (FPT_STM.1)...............................................................................................38
5.1.6.13 Extended: TSF Cryptographic Functionality Testing (FPT_TST_EXT.1) .........................................38
5.1.6.14 TSF Cryptographic Functionality Testing (Wireless LAN) (FPT_TST_EXT.1/WLAN) ......................38
5.1.6.15 Extended: TSF Integrity Checking (FPT_TST_EXT.2(1)).................................................................38
5.1.6.16 Extended: Trusted Update: TSF version query (FPT_TUD_EXT.1)................................................38
5.1.6.17 Extended: TSF Update Verification (FPT_TUD_EXT.2) .................................................................39
5.1.7 TOE access (FTA)....................................................................................................................................39
5.1.7.1 Extended: TSF- and User-initiated Locked State (FTA_SSL_EXT.1)...............................................39
5.1.7.2 Default TOE Access Banners (FTA_TAB.1)....................................................................................39
5.1.7.3 Wireless Network Access (FTA_WSE_EXT.1)................................................................................39
5.1.8 Trusted path/channels (FTP)..................................................................................................................39
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5.1.8.1 Extended: Trusted channel Communication (FTP_ITC_EXT.1).....................................................39
5.1.8.2 Trusted Channel Communication (Wireless LAN) (FTP_ITC_EXT.1/WLAN) .................................40
5.2 TOE Security Assurance Requirements ......................................................................................................40
5.2.1 Development (ADV)...............................................................................................................................40
5.2.1.1 Basic Functional Specification (ADV_FSP.1).................................................................................40
5.2.2 Guidance documents (AGD) ..................................................................................................................41
5.2.2.1 Operational User Guidance (AGD_OPE.1)....................................................................................41
5.2.2.2 Preparative Procedures (AGD_PRE.1)..........................................................................................41
5.2.3 Life-cycle support (ALC) .........................................................................................................................42
5.2.3.1 Labelling of the TOE (ALC_CMC.1) ...............................................................................................42
5.2.3.2 TOE CM Coverage (ALC_CMS.1)...................................................................................................42
5.2.3.3 Timely Security Updates (ALC_TSU_EXT.1)..................................................................................42
5.2.4 Tests (ATE) .............................................................................................................................................43
5.2.4.1 Independent Testing - Conformance (ATE_IND.1).......................................................................43
5.2.5 Vulnerability assessment (AVA).............................................................................................................43
5.2.5.1 Vulnerability Survey (AVA_VAN.1)...............................................................................................43
6. TOE Summary Specification.................................................................................................................................44
6.1 Security audit .............................................................................................................................................44
6.2 Cryptographic support ...............................................................................................................................46
6.3 User data protection..................................................................................................................................51
6.4 Identification and authentication ..............................................................................................................55
6.5 Security Management................................................................................................................................58
6.6 Protection of the TSF..................................................................................................................................58
6.7 TOE access..................................................................................................................................................62
6.8 Trusted path/channels...............................................................................................................................63
7. TSF Inventory.......................................................................................................................................................64
LIST OF TABLES
Table 1 TOE Security Functional Components ......................................................................................................19
Table 2 Security Management Functions ................................................................................................................32
Table 3 WLAN Security Management Functions...................................................................................................36
Table 4 EAL 1 augmented with ALC_TSU_EXT.1 Assurance Components.......................................................40
Table 5 Audit Events .................................................................................................................................................45
Table 6 Asymmetric Key Generation .........................................................................................................................46
Table 7 BoringSSL Cryptographic Algorithms.............................................................................................................48
Table 8 KDF Cryptographic Algorithms.......................................................................................................................48
Table 9 SDM845 Hardware Cryptographic Algorithms..............................................................................................48
Table 10 – Functional Categories................................................................................................................................53
Table 11 Power-up Cryptographic Algorithm Known Answer Tests .........................................................................61
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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 Pixel 3 and Pixel 3 XL provided by Google LLC. 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 – Pixel 3 and Pixel 3 XL (MDFPP31/WLANCEP10) Security Target
ST Version – Version 0.6
ST Date – 2019/07/17
1.2 TOE Reference
TOE Identification – Google LLC Pixel 3 and Pixel 3 XL
TOE Developer – Google LLC
Evaluation Sponsor – Google LLC
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1.3 TOE Overview
The Target of Evaluation (TOE) is Pixel 3 and Pixel 3 XL. The only variation between the two devices is the screen
and battery size, shown below.
Feature Pixel 3 Smartphone / Pixel 3 XL Smartphone
Display OLED 5.5", 18:9 ratio (1920x1080) / OLED 6.3", 18.5:9 (2560x1440)
Camera Rear 12.2 MP dual-pixel Standard-Angle Lens f/1.8 with LED Flash
Front Dual Cameras with 8 MP Lens f/2.2 (wide-angle) and f/1.8 (Normal)
Communications 4G LTE Network / Mobile Hotspot / Bluetooth 5.0 / Wi-Fi Direct / USB and Bluetooth
Tethering / Android Beam(NFC) / Media Server / Screen Sharing(Miracast) / HD Voice /
MIDI Device / MirrorLink / S-GPS, A-GPS and Qualcomm Service for Enhanced Location
Accuracy
Processor/
chipset
Processor: Qualcomm Snapdragon™ 845 up to 2.8 GHz x 4 + 1.7 GHz x 4 Octa-Core
SDM845, GPU: Adreno 630
RAM 4 GB RAM
Storage 64/128 GB internal memory (non-expandable)
Battery 2915 mAh / 3430 mAh
The TOE allows basic telephony features (make and receive phone calls, send and receive SMS/MMS messages) as
well as advanced network connectivity (allowing connections to both 802.11 Wi-Fi and 2G/3G/4G LTE mobile data
networks). The TOE supports using client certificates to connect to access points offering WPA2 networks with
802.1x/EAP-TLS, or alternatively connecting to cellular base stations when utilizing mobile data.
The TOE offers mobile applications an Application Programming Interface (API) including that provided by the
Android framework and supports API calls to the Android Management APIs.
1.4 TOE Description
The TOE is a mobile device to support enterprises and individual users alike. The Android 9.0 operating system
includes a Linux 4.9 kernel. Additional libraries are provided to developers to help ensure secure application
development and use for features such as Sensitive Data Protection.
The following models and versions are included in the evaluation:
Product Carrier OS version Kernel Build number WFA Cert#
Google Pixel 3 (blueline) Open Android 9.0 4.9.14
8
PQ3A.190605.003.A3 WFA77734
Google Pixel 3 XL (crosshatch) Open Android 9.0 4.9.14
8
PQ3A.190605.003.A3 WFA78505
By default, some features and settings must be enabled for the TOE to be in evaluated configuration. The following
features and settings must be enabled:
1. Enable the password on the lock screen
2. Disable SmartLock
3. Leave developer mode USB debugging in its default state of disabled
4. Disable Side Loading of Applications
5. VPN Full Tunnel Configuration
6. Enable Audit logging
Doing this ensures that the phone complies with the MDFPP requirements
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Please refer to the Admin Guide on how to configure the required settings and features.
1.4.1 TOE Architecture
The TOE provides a rich API to mobile applications and provides users installing an application the option to either
approve or reject an application based upon the API access that the application requires (or to grant applications
access at runtime).
The TOE also provides users with the ability to protect Data-At-Rest with AES encryption, including all user and
mobile application data stored in the user’s data partition. The TOE uses a key hierarchy that combines a REK with
the user’s password to provide protection to all user and application cryptographic keys stored in the TOE.
Finally, the TOE can interact with a Mobile Device Management (MDM) system (not part of this evaluation) to
allow enterprise control of the configuration and operation of the device so as to ensure adherence to enterprise-wide
policies (for example, restricting use of a corporate provided device’s camera, forced configuration of maximum
login attempts, pulling of audit logs off the TOE, etc.) as well as policies governing enterprise applications and data
(in a an employee-owned device [BYOD] scenario). An MDM is made up of two parts: the MDM agent and MDM
server. The MDM Agent is installed on the phone as an administrator with elevated permissions (allowing it to
change the relevant settings on the phone) while the MDM Server is used to issue the commands to the MDM
Agent. Neither portion of the MDM process is considered part of the TOE, and therefore not being directly
evaluated.
The TOE includes several different levels of execution including (from lowest to highest): hardware, a Trusted
Execution Environment, Android’s Linux kernel, and Android’s user space, which provides APIs allowing
applications to leverage the cryptographic functionality of the device.
1.4.1.1 Physical Boundaries
The TOE’s physical boundary is the physical perimeter of its enclosure. The software of the device is Android 9
running on the Qualcomm Snapdragon 845. The TOE does not include the user applications that run on top of the
operating system, but does include controls that limit application behavior. Further, the device provides support for
downloadable MDM agents to be installed to limit or permit different functionality of the device. There is no built-in
MDM agent pre-installed on the device.
The TOE communicates and interacts with 802.11-2012 Access Points and mobile data networks to establish
network connectivity, and through that connectivity interacts with MDM servers that allow administrative control of
the TOE.
1.4.1.2 Logical Boundaries
This section summarizes the security functions provided by Pixel 3 and Pixel 3 XL:
- Security audit
- Cryptographic support
- User data protection
- Identification and authentication
- Security management
- Protection of the TSF
- TOE access
- Trusted path/channels
1.4.1.2.1 Security audit
The TOE implements a security log, logcat, and intent logging that are each stored in a circular memory buffer of
various sizes. An MDM agent can read/fetch the security log and intents and then handle appropriately (potentially
storing the log to Flash or transmitting its contents to the MDM server). These log methods meet the logging
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requirements outlined by FAU_GEN.1 in MDFPPv3.1. Please see the Security audit section for further information
and specifics.
1.4.1.2.2 Cryptographic support
The TOE includes multiple cryptographic libraries with CAVP certified algorithms for a wide range of cryptograph-
ic functions including the following: asymmetric key generation and establishment, symmetric key generation, en-
cryption/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 stor-
age, and key and protected data destruction. These primitive cryptographic functions are used to implement security
protocols such as TLS, EAP-TLS, IPsec, and HTTPS and to encrypt the media (including the generation and protec-
tion of data and key encryption keys) used by the TOE. Many of these cryptographic functions are also accessible as
services to applications running on the TOE allowing application developers to ensure their application meets the
required criteria to remain compliant to MDFPP standards.
1.4.1.2.3 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. The TOE’s evaluated configuration supports Android Enterprise profiles
to provide additional separation between application and application data belonging to the Enterprise profile. Please
see the Admin Guide for additional details regarding how to set up and use Enterprise profiles.
1.4.1.2.4 Identification and authentication
The TOE supports a number of features related to identification and authentication. From a user perspective, except
for FCC mandated (making phone calls to an emergency number) or non-sensitive functions (e.g., choosing the
keyboard input method or taking screen shots), a password (i.e., Password Authentication Factor) must be correctly
entered to unlock the TOE. Also, even when unlocked, the TOE requires the user re-enter the password to change
the password. Passwords are obscured when entered so they cannot be read from the TOE's display and the
frequency of entering passwords is limited and when a configured number of failures occurs, the TOE will be wiped
to protect its contents. Passwords can be constructed using upper and lower cases characters, numbers, and special
characters and passwords up to 16 characters are supported.
The TOE can also serve as an 802.1X supplicant and can both use X.509v3 and validate certificates for EAP-TLS,
TLS, and HTTPS exchanges.
1.4.1.2.5 Security management
The TOE provides all the interfaces necessary to manage the security functions identified throughout this Security
Target as well as other functions commonly found in mobile devices. Many of the available functions are available
to users of the TOE 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 will remove
Enterprise applications and remove MDM policies.
1.4.1.2.6 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 through the use of the application processor’s hardware. The TOE disallows all read access to the Root
Encryption Key and retains all keys derived from the REK within its the Trusted Execution Environment (TEE).
Application software can only use keys derived from the REK by reference and receive the result.
The TOE also provides its own timing mechanism to ensure that reliable time information is available (e.g., for log
accountability). It enforces read, write, and execute memory page protections, uses address space layout
randomization, and stack-based buffer overflow protections to minimize the potential to exploit application flaws. It
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also protects itself from modification by applications as well as to isolate the address spaces of applications from
one another to protect those applications.
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 of the self-tests fail, the TOE will 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 as all applications must
have signatures (even if self-signed).
1.4.1.2.7 TOE access
The TOE can be locked, obscuring its display, by the user or after a configured interval of inactivity. The TOE also
has the capability to display an administrator specified (using the TOE’s MDM API) advisory message (banner)
when the user unlocks the TOE for the first use after reboot.
The TOE is also able to attempt to connect to wireless networks as configured.
1.4.1.2.8 Trusted path/channels
The TOE supports the use of IEEE 802.11-2012, 802.1X, and EAP-TLS to secure communications channels
between itself and other trusted network devices.
1.4.2 TOE Documentation
Google Android 9.0 (Pixel 3/3XL) Guidance Documentation, Version 2.1, 07/16/2019 [Admin Guide]
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2. Conformance Claims
This TOE is conformant to the following CC specifications:
● Common Criteria for Information Technology Security Evaluation Part 2: Security functional components,
Version 3.1, Revision 5, April 2017.
● Part 2 Extended
● Common Criteria for Information Technology Security Evaluation Part 3: Security assurance components,
Version 3.1 Revision 5, April 2017.
● Part 3 Conformant
● Package Claims:
● Protection Profile for Mobile Device Fundamentals, Version 3.1, 16 June 2017 and General
Purpose Operating Systems Protection Profile/Mobile Device Fundamentals Protection Profile
Extended Package (EP) Wireless Local Area Network (WLAN) Clients, Version 1.0, 08 February
2016 (MDFPP31/WLANCEP10)
● Technical Decisions:
TD No. Applied? Rationale
TD0194 – WLANCEP10 Yes Impacts required audit events
TD0236 – MDFPP31 No Superseded by TD0244
TD0244 – MDFPP31/WLANCEP10 Yes Allows additional TLSC curves
TD0301 – MDFPP31 Yes Impacts Assurance Activities and allows for
assignment for FIA_BMG_EXT.1.1
TD0304 – MDFPP31 Yes Impacts Assurance Activities
TD0305 – MDFPP31 Yes Impacts Assurance Activities
TD0346 – MDFPP31 Yes Removes selection from FMT_SMF_EXT.2.1
TD0347 – MDFPP31 No Use Case 2 not selected
TD0351 – MDFPP31 Yes Adds DEK selections to FCS_CKM_EXT.2.1
TD0366 – MDFPP31 Yes FCS_COP.1(5) updated to reflect scrypt
TD0369 – MDFPP31 Yes LTTCKM present.
TD0371 – MDFPP31 No Use Case 2 not selected
TD0413 – MDFPP31 Yes Any Allowed PP-Module
TD0426 – MDFPP31 Yes Impacts Assurance Activities
2.1 Conformance Rationale
The ST conforms to the MDFPP31/WLANCEP10. 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 MDFPP31/WLANCEP10 and this section reproduces only the
corresponding Security Objectives for operational environment for reader convenience. The
MDFPP31/WLANCEP10 offers additional information about the identified security objectives, but that has not been
reproduced here and the MDFPP31/WLANCEP10 should be consulted if there is interest in that material.
In general, the MDFPP31/WLANCEP10 has defined Security Objectives appropriate for mobile device and as such
are applicable to the Pixel 3 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.NO_TOE_BYPASS Information cannot flow between external and internal networks located in different
enclaves without passing through the TOE.
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.
OE.TRUSTED_ADMIN TOE Administrators are trusted to follow and apply all administrator guidance in a trusted
manner.
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4. Extended Components Definition
All of the extended requirements in this ST have been drawn from the MDFPP31/WLANCEP10. The
MDFPP31/WLANCEP10 defines the following extended requirements and since they are not redefined in this ST
the MDFPP31/WLANCEP10 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_SRV_EXT.2: 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: TLS Protocol
- FCS_TLSC_EXT.2: Extended: TLS Protocol
- FCS_TLSC_EXT.1/WLAN: Extensible Authentication Protocol-Transport Layer Security
- FCS_TLSC_EXT.2/WLAN: TLS Client Protocol
- FDP_ACF_EXT.1: Extended: Security access control
- FDP_ACF_EXT.2: Extended: Security access control
- FDP_DAR_EXT.1: Extended: Protected Data Encryption
- FDP_DAR_EXT.2: Extended: Sensitive Data Encryption
- FDP_IFC_EXT.1: Extended: Subset information flow control
- FDP_PBA_EXT.1: Extended: Storage of Critical Biometric Parameters
- FDP_STG_EXT.1: Extended: User Data Storage
- FDP_UPC_EXT.1: Extended: Inter-TSF user data transfer protection
- FIA_AFL_EXT.1: Extended: Authentication failure handling
- FIA_BLT_EXT.1: Extended: Bluetooth User Authorization
- FIA_BLT_EXT.2: Extended: Bluetooth Mutual Authentication
- FIA_BLT_EXT.3: Extended: Rejection of Duplicate Bluetooth Connections
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- FIA_BLT_EXT.4: Extended: Secure Simple Pairing
- FIA_BLT_EXT.6: Extended: Bluetooth User Authorization
- FIA_BMG_EXT.1: Extended: Accuracy of Biometric Authentication
- FIA_PAE_EXT.1: Port Access Entity 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_X509_EXT.1: Extended: Validation of certificates
- FIA_X509_EXT.2: Extended: X509 certificate authentication
- FIA_X509_EXT.2/WLAN: X.509 Certificate Authentication (EAP-TLS)
- FIA_X509_EXT.3: Extended: Request Validation of certificates
- FMT_MOF_EXT.1: Extended: Management of security functions behavior
- FMT_SMF_EXT.1: Extended: Specification of Management Functions
- FMT_SMF_EXT.1/WLAN: Specification of Management Functions (Wireless LAN)
- FMT_SMF_EXT.2: Extended: Specification of Remediation Actions
- FMT_SMF_EXT.3: Extended: Current Administrator
- 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_AEX_EXT.5: Extended: Anti-Exploitation Services (ASLR)
- FPT_BBD_EXT.1: Extended: Application Processor Mediation
- FPT_JTA_EXT.1: Extended: JTAG Disablement
- 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.1/WLAN: TSF Cryptographic Functionality Testing (Wireless LAN)
- FPT_TST_EXT.2(1): Extended: TSF Integrity Checking
- FPT_TUD_EXT.1: Extended: Trusted Update: TSF version query
- FPT_TUD_EXT.2: Extended: TSF Update Verification
- FTA_SSL_EXT.1: Extended: TSF- and User-initiated Locked State
- FTA_WSE_EXT.1: Wireless Network Access
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- FTP_ITC_EXT.1: Extended: Trusted channel Communication
- FTP_ITC_EXT.1/WLAN: Trusted Channel Communication (Wireless LAN)
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 MDFPP31/WLANCEP10. The refinements and operations already
performed in the MDFPP31/WLANCEP10 are not identified (e.g., highlighted) here, rather the requirements have
been copied from the MDFPP31/WLANCEP10 and any residual operations have been completed herein. Of
particular note, the MDFPP31/WLANCEP10 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 MDFPP31/WLANCEP10 which includes all the SARs for EAL 1. However, the
SARs are effectively refined since requirement-specific 'Assurance Activities' are defined in the
MDFPP31/WLANCEP10 that serve to ensure corresponding evaluations will yield more practical and consistent
assurance than the EAL 1 assurance requirements alone. The MDFPP31/WLANCEP10 should be consulted for the
assurance activity definitions.
5.1 TOE Security Functional Requirements
The following table identifies the SFRs that are satisfied by Pixel 3 TOE.
Requirement Class Requirement Component
FAU: Security audit FAU_GEN.1: Audit Data Generation
FAU_STG.1: Audit Storage Protection
FAU_STG.4: Prevention of Audit Data Loss
FCS: Cryptographic support FCS_CKM.1: Cryptographic key generation
FCS_CKM.1/WLAN: Cryptographic Key
Generation (Symmetric Keys for WPA2
Connections)
FCS_CKM.2(1): Cryptographic key establishment
FCS_CKM.2(2): Cryptographic key establishment
(While device is locked)
FCS_CKM.2/WLAN: Cryptographic Key
Distribution (GTK)
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
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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_SRV_EXT.2: 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: TLS Protocol
FCS_TLSC_EXT.2: Extended: TLS Protocol
FCS_TLSC_EXT.1/WLAN: Extensible
Authentication Protocol-Transport Layer Security
FCS_TLSC_EXT.2/WLAN: TLS Client Protocol
FDP: User data protection FDP_ACF_EXT.1: Extended: Security access
control
FDP_ACF_EXT.2: Extended: Security access
control
FDP_DAR_EXT.1: Extended: Protected Data
Encryption
FDP_DAR_EXT.2: Extended: Sensitive Data
Encryption
FDP_IFC_EXT.1: Extended: Subset information
flow control
FDP_PBA_EXT.1: Extended: Storage of Critical
Biometric Parameters
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: Extended: Authentication failure
handling
FIA_BLT_EXT.1: Extended: Bluetooth User
Authorization
FIA_BLT_EXT.2: Extended: Bluetooth Mutual
Authentication
FIA_BLT_EXT.3: Extended: Rejection of
Duplicate Bluetooth Connections
FIA_BLT_EXT.4: Extended: Secure Simple Pairing
FIA_BLT_EXT.6: Extended: Bluetooth User
Authorization
FIA_BMG_EXT.1: Extended: Accuracy of
Biometric Authentication
FIA_PAE_EXT.1: Port Access Entity
Authentication
FIA_PMG_EXT.1: Extended: Password
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Management
FIA_TRT_EXT.1: Extended: Authentication
Throttling
FIA_UAU.5: Multiple Authentication Mechanisms
FIA_UAU.6(1): Re-Authentication
FIA_UAU.6(2): Re-Authentication
FIA_UAU.7: Protected authentication feedback
FIA_UAU_EXT.1: Extended: Authentication for
Cryptographic Operation
FIA_UAU_EXT.2: Extended: Timing of
Authentication
FIA_X509_EXT.1: Extended: Validation of
certificates
FIA_X509_EXT.2: Extended: X509 certificate
authentication
FIA_X509_EXT.2/WLAN: X.509 Certificate
Authentication (EAP-TLS)
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.1/WLAN: Specification of
Management Functions (Wireless LAN)
FMT_SMF_EXT.2: Extended: Specification of
Remediation Actions
FMT_SMF_EXT.3: Extended: Current
Administrator
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_AEX_EXT.5: Extended: Anti-Exploitation
Services (ASLR)
FPT_BBD_EXT.1: Extended: Application
Processor Mediation
FPT_JTA_EXT.1: Extended: JTAG Disablement
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.1/WLAN: TSF Cryptographic
Functionality Testing (Wireless LAN)
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FPT_TST_EXT.2(1): Extended: TSF Integrity
Checking
FPT_TUD_EXT.1: Extended: Trusted Update: TSF
version query
FPT_TUD_EXT.2: Extended: TSF Update
Verification
FTA: TOE access FTA_SSL_EXT.1: Extended: TSF- and User-
initiated Locked State
FTA_TAB.1: Default TOE Access Banners
FTA_WSE_EXT.1: Wireless Network Access
FTP: Trusted path/channels FTP_ITC_EXT.1: Extended: Trusted channel
Communication
FTP_ITC_EXT.1/WLAN: Trusted Channel
Communication (Wireless LAN)
Table 1 TOE Security Functional Components
5.1.1 Security audit (FAU)
5.1.1.1 Audit Data Generation (FAU_GEN.1)
FAU_GEN.1.1
The TSF shall be able to generate an audit record of the following auditable events:
1. Start-up and shutdown of the audit functions
2. All auditable events for the not selected level of audit
3. All administrative actions
4. Start-up and shutdown of the Rich OS
5. Insertion or removal of removable media
6. Specifically defined auditable events in Table 1
7. [No other auditable events]
8. [Specifically defined auditable events in Table 2]
FAU_GEN.1.2
The TSF shall record within each audit record at least the following information:
1. Date and time of the event
2. type of event
3. subject identity
4. the outcome (success or failure) of the event
5. additional information in Table 1
6. [no additional information]
5.1.1.2 Audit Storage Protection (FAU_STG.1)
FAU_STG.1.1
The TSF shall protect the stored audit records in the audit trail from unauthorized deletion.
FAU_STG.1.2
The TSF shall be able to prevent unauthorized modifications to the stored audit records in the audit trail.
5.1.1.3 Prevention of Audit Data Loss (FAU_STG.4)
FAU_STG.4.1
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The TSF shall overwrite the oldest stored audit records if the audit trail is full.
5.1.2 Cryptographic support (FCS)
5.1.2.1 Cryptographic key generation (FCS_CKM.1)
FCS_CKM.1.1
The TSF shall generate asymmetric cryptographic keys in accordance with a specified cryptographic key generation
algorithm [
RSA schemes using cryptographic key sizes of 2048-bit or greater that meet FIPS PUB 186-4, 'Digital
Signature Standard (DSS)', Appendix B.3,
ECC schemes using ['NIST curves' P-384 and [P-256] that meet the following: FIPS PUB 186-4,
'Digital Signature Standard (DSS)', Appendix B.4]].
5.1.2.2 Cryptographic Key Generation (Symmetric Keys for WPA2 Connections) (FCS_CKM.1/WLAN)
FCS_CKM.1.1/WLAN
Refinement: The TSF shall generate symmetric cryptographic keys in accordance with a specified cryptographic key
generation algorithm PRF-384 and [PRF-704] and specified cryptographic key sizes 128 bits and [256 bits] using a
Random Bit Generator as specified in FCS_RBG_EXT.1 that meet the following: IEEE 802.11-2012 and [IEEE
802.11ac-2014].
5.1.2.3 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',
and
[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'].
5.1.2.4 Cryptographic key establishment (While device is locked) (FCS_CKM.2(2))
FCS_CKM.2(2).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",]
for the purposes of encrypting sensitive data received while the device is locked.
5.1.2.5 Cryptographic Key Distribution (GTK) (FCS_CKM.2/WLAN)
FCS_CKM.2.1/WLAN
Refinement: The TSF shall decrypt Group Temporal Key in accordance with a specified cryptographic key
distribution method AES Key Wrap in an EAPOL-Key frame that meets the following: RFC 3394 for AES Key
Wrap, 802.11-2012 for the packet format and timing considerations and does not expose the cryptographic keys.
5.1.2.6 Extended: Cryptographic Key Support (FCS_CKM_EXT.1)
FCS_CKM_EXT.1.1
The TSF shall support [immutable hardware] REK(s) with a [symmetric] key of strength [256 bits].
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FCS_CKM_EXT.1.2
Each REK shall be hardware-isolated from Rich OS on the TSF in runtime.
FCS_CKM_EXT.1.3
Each REK shall be generated by a RBG in accordance with FCS_RBG_EXT.1.
5.1.2.7 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 [256] bits.
(TD0351 applied)
5.1.2.8 Extended: Cryptographic Key Generation (FCS_CKM_EXT.3)
FCS_CKM_EXT.3.1
The TSF shall use [
asymmetric KEKs of [150-bit] security strength,
symmetric KEKs of [256-bit] security strength corresponding to at least the security strength of the keys
encrypted by the KEK].
FCS_CKM_EXT.3.2
The TSF shall generate all KEKs using one of the following methods:
Derive the KEK from a Password Authentication Factor according to FCS_COP.1.1(5)
and
[Generate the KEK using an RBG that meets this profile (as specified in FCS_RBG_EXT.1),
Generate the KEK using a key generation scheme that meets this profile (as specified in FCS_CKM.1),
Combine the KEK from other KEKs in a way that preserves the effective entropy of each factor by
[encrypting one key with another]]. (TD0366 applied)
5.1.2.9 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].
-- 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 by 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].
-> Note: no non-volatile flash memory w/o wear leveling exists on this TOE.
-- 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 a single
direct overwrite with a random pattern that is changed before each write.
FCS_CKM_EXT.4.2
The TSF shall destroy all plaintext keying material and critical security parameters when no longer needed.
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5.1.2.10 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 nonvolatile memory by following the
requirements in FCS_CKM_EXT.4.1,
Overwriting all Protected Data according to the following rules:
-- For 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 by a read-verify.
-- For 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].
-- For 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
a single direct overwrite with a random pattern that is changed before each write.].
FCS_CKM_EXT.5.2
The TSF shall perform a power cycle on conclusion of the wipe procedure.
5.1.2.11 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.
5.1.2.12 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 Key Wrap (KW) (as defined in NIST SP 800-38F),
AES-GCM (as defined in NIST SP 800-38D),
AES-XTS (as defined in NIST SP 800-38E) mode,
AES-CCMP-256 (as defined in NIST SP800-38C and IEEE 802.11ac-2013)]
and cryptographic key sizes 128-bit key sizes and [256-bit key sizes].
5.1.2.13 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.
5.1.2.14 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-384 and [P- 256] that meet the following: FIPS PUB 186-4, 'Digital
Signature Standard (DSS)', Section 5].
5.1.2.15 Cryptographic operation (FCS_COP.1(4))
FCS_COP.1(4).1
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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 [256,
384, 512-bits] 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'.
5.1.2.16 Cryptographic operation (FCS_COP.1(5))
FCS_COP.1(5).1
The TSF shall perform conditioning in accordance with a specified cryptographic algorithm HMAC-[SHA-256]
using a salt, and [[scrypt]] and output cryptographic key sizes [256] that meet the following: NIST [no standard].
(TD0366 applied)
5.1.2.17 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.1).
FCS_HTTPS_EXT.1.3
The TSF shall notify the application and [not establish the connection] if the peer certificate is deemed invalid.
5.1.2.18 Extended: Initialization Vector Generation (FCS_IV_EXT.1)
FCS_IV_EXT.1.1
The TSF shall generate IVs in accordance with Table 11: References and IV Requirements for NIST-approved
Cipher Modes.
5.1.2.19 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), a SHA-256 Hardware Hash_DRBG].
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.
5.1.2.20 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 [selected algorithms] in FCS_CKM.2(2)
The following algorithms in FCS_COP.1(1): AES-CBC, [AES-GCM]
All mandatory and selected algorithms in FCS_COP.1(2)
All mandatory and selected algorithms in FCS_COP.1(3)
All mandatory and selected algorithms in FCS_COP.1(4)
[All mandatory and [selected algorithms] in FCS_CKM.1].
5.1.2.21 Extended: Cryptographic Algorithm Services (FCS_SRV_EXT.2)
FCS_SRV_EXT.2.1
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The TSF shall provide a mechanism for applications to request the TSF to perform the following cryptographic
operations:
● Algorithms in FCS_COP.1(1)
● Algorithms in FCS_COP.1(3)
by keys stored in the secure key storage.
5.1.2.22 Extended: Cryptographic Key Storage (FCS_STG_EXT.1)
FCS_STG_EXT.1.1
The TSF shall provide [software-based] secure key storage for asymmetric private keys and [symmetric keys,
persistent secrets].
FCS_STG_EXT.1.2
The TSF shall be capable of importing keys/secrets into the secure key storage upon request of [the user, the
administrator] 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]
5.1.2.23 Extended: Encrypted Cryptographic Key Storage (FCS_STG_EXT.2)
FCS_STG_EXT.2.1
The TSF shall encrypt all DEKs, KEKs, [WPA2 WiFi PSK, Bluetooth Keys] and [all software-based key storage]
by KEKs that are
[
Protected by the REK with [
encryption by a KEK chaining from a REK,
encryption by a KEK that is derived from a REK
],
Protected by the REK and the password with [
encryption by a KEK chaining to a REK and the password-derived or biometric-unlocked KEK,
encryption by a KEK that is derived from a REK and the password derived or biometric-
unlocked KEK
]
].
FCS_STG_EXT.2.2
DEKs, KEKs, [WPA2 WiFi PSK, Bluetooth Keys] and [all software-based key storage]] shall be encrypted using
one of the following methods:
[
using a SP800-56B key establishment scheme,
using AES in the [
GCM,
CCM mode]
].
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5.1.2.24 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 [long-term trusted channel key material,
all software-based key storage] by [[GCM, CCM] cipher mode for encryption according to FCS_STG_EXT.2].
FCS_STG_EXT.3.2
The TSF shall verify the integrity of the [MAC] of the stored key prior to use of the key.
5.1.2.25 Extended: TLS Protocol (FCS_TLSC_EXT.1)
FCS_TLSC_EXT.1.1
The TSF shall implement TLS 1.2 (RFC 5246) supporting the following ciphersuites:
Mandatory Ciphersuites:
[TLS_RSA_WITH_AES_128_CBC_SHA256 as defined in RFC 5246,
TLS_RSA_WITH_AES_256_CBC_SHA256 as defined in RFC 5246]
Optional Ciphersuites:
[TLS_RSA_WITH_AES_256_GCM_SHA384 as defined in RFC 5288,
TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 as defined in RFC 5289,
TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 as defined in RFC 5289,
TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 as defined in RFC 5289,
TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 as defined in RFC 5289,
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 presented identifier matches the reference identifier according to RFC 6125.
FCS_TLSC_EXT.1.3
The TSF shall not establish a trusted channel if the peer certificate is invalid.
FCS_TLSC_EXT.1.4
The TSF shall support mutual authentication using X.509v3 certificates.
5.1.2.26 Extended: TLS Protocol (FCS_TLSC_EXT.2)
FCS_TLSC_EXT.2.1
The TSF shall present the Supported Elliptic Curves Extension in the Client Hello handshake message with the
following NIST curves: [secp256r1, secp384r1]. (TD0244 applied, supersedes TD0236)
5.1.2.27 Extensible Authentication Protocol-Transport Layer Security (FCS_TLSC_EXT.1/WLAN)
FCS_TLSC_EXT.1.1/WLAN
The TSF shall implement TLS 1.0 and [TLS 1.1 (RFC 4346), TLS 1.2 (RFC 5246)] in support of the EAP-TLS
protocol as specified in RFC 5216 supporting the following ciphersuites:
Mandatory Ciphersuites in accordance with RFC 5246:
TLS_RSA_WITH_AES_128_CBC_SHA
Optional Ciphersuites:
[TLS_RSA_WITH_AES_256_CBC_SHA as defined in RFC 5246,
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_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,
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TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 as defined in RFC 5430,
TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 as defined in RFC 5430,
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_RSA_WITH_AES_128_GCM_SHA256 as defined in RFC 5289,
TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 as defined in RFC 5289].
FCS_TLSC_EXT.1.2/WLAN
The TSF shall generate random values used in the EAP-TLS exchange using the RBG specified in
FCS_RBG_EXT.1.
FCS_TLSC_EXT.1.3/WLAN
The TSF shall use X509 v3 certificates as specified in FIA_X509_EXT.1.
FCS_TLSC_EXT.1.4/WLAN
The TSF shall verify that the server certificate presented includes the Server Authentication purpose (id-kp 1 with
OID 1.3.6.1.5.5.7.3.1) in the extendedKeyUsage field.
FCS_TLSC_EXT.1.5/WLAN
The TSF shall allow an authorized administrator to configure the list of CAs that are allowed to sign authentication
server certificates that are accepted by the TOE.
FCS_TLSC_EXT.1.6/WLAN
The TSF shall allow an authorized administrator to configure the list of algorithm suites that may be proposed and
accepted during the EAP-TLS exchanges.
5.1.2.28 TLS Client Protocol (FCS_TLSC_EXT.2/WLAN)
FCS_TLSC_EXT.2.1/WLAN
The TSF shall present the Supported Elliptic Curves Extension in the Client Hello with the following NIST curves:
[secp256r1, secp384r1]. (TD0244 applied):
5.1.3 User data protection (FDP)
5.1.3.1 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 [applications, groups of applications] from accessing
[all] data stored by other [applications, groups of applications]. Exceptions may only be explicitly authorized for
such sharing by [a common application developer, no one].
ST Application Note: “common application developer” applies only to applications, "no one" can authorize
exceptions for the personal and enterprise profiles to share data.
5.1.3.2 Extended: Security access control (FDP_ACF_EXT.2)
FDP_ACF_EXT.2.1
The TSF shall provide a separate [address book, calendar, keychain] for each application group and only allow
applications within that process group to access the resource. Exceptions may only be explicitly authorized for such
sharing by [the administrator, no one]
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ST Application Note: “the administrator” applies only to the address book, the other selections cannot be shared
between application groups.
5.1.3.3 Extended: Protected Data Encryption (FDP_DAR_EXT.1)
FDP_DAR_EXT.1.1
Encryption shall cover all protected data.
FDP_DAR_EXT.1.2
Encryption shall be performed using DEKs with AES in the [XTS] mode with key size [256] bits.
5.1.3.4 Extended: Sensitive Data Encryption (FDP_DAR_EXT.2)
FDP_DAR_EXT.2.1
The TSF shall provide a mechanism for applications to mark data and keys as sensitive.
FDP_DAR_EXT.2.2
The TSF shall use an asymmetric key scheme to encrypt and store sensitive data received while the product is
locked.
FDP_DAR_EXT.2.3
The TSF shall encrypt any stored symmetric key and any stored private key of the asymmetric key(s) used for the
protection of sensitive data according to FCS_STG_EXT.2.1 selection 2.
FDP_DAR_EXT.2.4
The TSF shall decrypt the sensitive data that was received while in the locked state upon transitioning to the
unlocked state using the asymmetric key scheme and shall re-encrypt that sensitive data using the symmetric key
scheme.
5.1.3.5 Extended: Subset information flow control (FDP_IFC_EXT.1)
FDP_IFC_EXT.1.1
The TSF shall [provide an interface which allows a VPN client to protect all IP traffic using IPsec] with the
exception of IP traffic required to establish the VPN connection.
5.1.3.6 Extended: Storage of Critical Biometric Parameters
FDP_PBA_EXT.1.1
The TSF shall protect the authentication template [using a password as an additional factor].
5.1.3.7 Extended: User Data Storage (FDP_STG_EXT.1)
FDP_STG_EXT.1.1
The TSF shall provide protected storage for the Trust Anchor Database.
5.1.3.8 Extended: Inter-TSF user data transfer protection (FDP_UPC_EXT.1)
FDP_UPC_EXT.1.1
The TSF shall provide a means for non-TSF applications executing on the TOE to use TLS, HTTPS, Bluetooth
BR/EDR, and [Bluetooth LE] 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
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The TSF shall permit the non-TSF applications to initiate communication via the trusted channel.
5.1.4 Identification and authentication (FIA)
5.1.4.1 Extended: Authentication failure handling (FIA_AFL_EXT.1)
FIA_AFL_EXT.1.1
The TSF shall consider password and [fingerprint] as critical authentication mechanisms.
FIA_AFL_EXT.1.2
The TSF shall detect when a configurable positive integer within [0 and 2,147,483,647] of [non-unique]
unsuccessful authentication attempts occur related to last successful authentication for each authentication
mechanism.
FIA_AFL_EXT.1.3
The TSF shall maintain the number of unsuccessful authentication attempts that have occurred upon power off.
FIA_AFL_EXT.1.4
When the defined number of unsuccessful authentication attempts has exceeded the maximum allowed for a given
authentication mechanism, all future authentication attempts will be limited to other available authentication
mechanisms, unless the given mechanism is designated as a critical authentication mechanism.
FIA_AFL_EXT.1.5
When the defined number of unsuccessful authentication attempts for the last available authentication mechanism or
single critical authentication mechanism has been surpassed, the TSF shall perform a wipe of all protected data.
FIA_AFL_EXT.1.6
The TSF shall increment the number of unsuccessful authentication attempts prior to notifying the user that the
authentication was unsuccessful.
5.1.4.2 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.
5.1.4.3 Extended: Bluetooth Mutual Authentication (FIA_BLT_EXT.2)
FIA_BLT_EXT.2.1
The TSF shall require Bluetooth mutual authentication between devices prior to any data transfer over the Bluetooth
link.
5.1.4.4 Extended: Rejection of Duplicate Bluetooth Connections (FIA_BLT_EXT.3)
FIA_BLT_EXT.3.1
The TSF shall discard connection attempts from a Bluetooth device address (BD_ADDR) to which a current
connection already exists.
5.1.4.5 Extended: Secure Simple Pairing (FIA_BLT_EXT.4)
FIA_BLT_EXT.4.1
The TOE shall support Bluetooth Secure Simple Pairing, both in the host and the controller. Furthermore, Secure
Simple Pairing shall be used during the pairing process if the remote device also supports it.
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5.1.4.6 Extended: Bluetooth User Authorization (FIA_BLT_EXT.6)
FIA_BLT_EXT.6.1
The TSF shall require explicit user authorization before granting trusted remote devices access to services associated
with the following Bluetooth profiles: [All Bluetooth profiles], and shall require explicit user authorization before
granting untrusted remote devices access to services associated with the following Bluetooth profiles: [All Bluetooth
profiles].
5.1.4.7 Extended: Accuracy of Biometric Authentication (FIA_BMG_EXT.1)
FIA_BMG_EXT.1.1
The one-attempt BAF False Accept Rate (FAR) for [fingerprint] shall not exceed [1:100,000] with a one-attempt
BAF False Reject Rate (FRR) not to exceed 1 in [1:20]. (TD0301 applied)
FIA_BMG_EXT.1.2
The overall System Authentication False Accept Rate (SAFAR) shall be no greater than 1 in [1:5,000] within a 1%
margin.
5.1.4.8 Port Access Entity 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.
5.1.4.9 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: [! @ # $ % ^ & * ( ) [= + - _ ` ~ \ | ] } [ { ‘ “ ; : / ? . > , < ]] ;
2. Password length up to [16] characters shall be supported.
5.1.4.10 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] for all authentication mechanisms selected in FIA_UAU.5.1. The minimum delay shall be such that no
more than 10 attempts can be attempted per 500 milliseconds.
5.1.4.11 Multiple Authentication Mechanisms (FIA_UAU.5)
FIA_UAU.5.1
The TSF shall provide password and [fingerprint] to support user authentication.
FIA_UAU.5.2
The TSF shall authenticate any user's claimed identity according to the [following rules:
To authenticate unlocking the device immediately after boot (first unlock after reboot):
- User passwords are required after reboot to unlock the user's Credential encrypted (CE files) and
keystore keys. Fingerprint authentication is disabled immediately after boot.
To authenticate unlocking the device after device lock (not following a reboot):
- The TOE verifies user credentials (password or fingerprint) via the gatekeeper or fingerprint trusted
application (running inside the Trusted Execution Environment, TEE), which compares the entered
credential to a derived value or template.
To change protected settings or issue certain commands:
- The TOE requires password after a reboot, when changing settings (Screen lock, Fingerprint, and Smart
Lock settings), and when factory resetting.”
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].
5.1.4.12 Re-Authentication (FIA_UAU.6(1))
FIA_UAU.6(1).1
The TSF shall re-authenticate the user via the Password Authentication Factor under the conditions attempted
change to any supported authentication mechanisms.
5.1.4.13 Re-Authentication (FIA_UAU.6(2))
FIA_UAU.6(2).1
The TSF shall re-authenticate the user via an authentication factor defined in FIA_UAU.5.1 under the conditions
TSF-initiated lock, user-initiated lock, [no other conditions].
5.1.4.14 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.
5.1.4.15 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 [all software-based key storage] at startup.
5.1.4.16 Extended: Timing of Authentication (FIA_UAU_EXT.2)
FIA_UAU_EXT.2.1
The TSF shall allow [[
- Choosing of the keyboard input method,
- Make emergency phone calls,
- Take screen shots (stored internally),
- Receive calls,
- Turn TOE off,
- Restart TOE,
- Enable/disable airplane mode,
- Take photos (stored internally) - can view and delete photos taken since last screen lock,
- Toggle: WiFi, Bluetooth, Do not Disturb Mode, Flashlight, Auto-rotate, Batter Saver Mode, Mobile
Data, Night Light Mode
o Note: WiFi/Bluetooth can be toggled to disconnect or connect to a remembered connection, but
any new connection establishment requires a device unlock
- Adjust brightness level
- Adjust volume level or silence device
- View/clear notifications
- View Clock/Date
- View Lock Screen Banner
]] 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.
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5.1.4.17 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 [the Online Certificate Status
Protocol (OCSP) as specified in RFC 2560]
- The TSF shall validate the extendedKeyUsage field according to the following rules:
-- 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
-- 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
-- (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.
5.1.4.18 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 [TLS and HTTPS],
and [no additional uses].
FIA_X509_EXT.2.2
When the TSF cannot establish a connection to determine the revocation status of a certificate, the TSF shall [not
accept the certificate].
5.1.4.19 X.509 Certificate Authentication (EAP-TLS) (FIA_X509_EXT.2/WLAN)
FIA_X509_EXT.2.1/WLAN
The TSF shall use X.509v3 certificates as defined by RFC 5280 to support authentication for EAP-TLS exchanges.
FIA_X509_EXT.2.2/WLAN
When the TSF cannot establish a connection to determine the validity of a certificate, the TSF shall [accept the
certificate].
5.1.4.20 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.
5.1.5 Security management (FMT)
5.1.5.1 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 2 Security Management Functions
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to the user.
FMT_MOF_EXT.1.2
The TSF shall restrict the ability to perform the functions in column 5 of Table 2 Security Management Functions
to the administrator when the device is enrolled and according to the administrator-configured policy.
5.1.5.2 Extended: Specification of Management Functions (FMT_SMF_EXT.1)
FMT_SMF_EXT.1.1
The TSF shall be capable of performing the functions in column 2 of Table 2 Security Management Functions.
Table 2 Security Management Functions
Management Function
FMT_SMF_EXT.1.1
FMT_MOF_EXT.1.1
Administrator
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.
Length: an integer value of characters
Complexity: Unspecified, Something, Numeric, Alphabetic, Alphanumeric, Complex.
Lifetime: an integer value of seconds (0 = no maximum).
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.
Screen lock timeout: an integer number of minutes before the TOE locks (0 = no lock timeout)
Authentication failures: an integer number (-2,147,483,648 to 2,147,483,648 [negative
integers and zero means no limit]).
M M M
3. enable/disable the VPN protection:
a. across device
[ c. no other method]
Both users (using the TOE’s settings UI) and administrator (using the TOE’s MDM APIs) can
configure a third-party VPN client and then enable the VPN client to protect traffic. The User
can set up VPN protection, but if an admin enables VPN protection, the user cannot disable it.
M I I
4. enable/disable [GPS, Bluetooth BR/DR, Bluetooth LE, NFC,
Wi-Fi, cellular]
M
M I
I I
Status Markers:
M – Mandatory
I – Implemented optional
function
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The administrator can disable the radios using the TOE’s MDM APIs. Once disabled, a user
cannot enable the radio. The TOE’s radios operate at frequencies of 2.4 GHz (NFC/Bluetooth),
2.4/5 GHz (Wi-Fi), and 850, 900, 1800, 1900 MHz (4G/LTE).
5. enable/disable [microphone, camera]:
a. across device (microphone),
[ b. on a per-app basis (microphone, camera)]
An administrator can enable/disable the device’s microphone via an MDM API. Once the
microphone has been disabled, the user cannot re-enable it until the administrator enables it.
In the user’s settings, a user can view a permission by type (i.e. camera, microphone). The user
can access this by going to “Settings” -> “App Permissions” -> Selecting the permission and
revoking any applications.
M
M
I I
6. transition to the locked state
Both users (using the TOE’s settings UI) and administrators (using the TOE’s MDM APIs) can
transition the TOE into a locked state.
M M
7. full wipe of protected data
Both users (using the TOE’s settings UI) and administrators (using the TOE’s MDM APIs) can
force the TOE to perform a full wipe (factory reset) of data.
M M
8. configure application installation policy by:
a. restricting the sources of applications,
c. denying installation of applications]
The administrator using the TOE’s MDM APIs can configure the TOE so that applications
cannot be installed and can also block the use of the Google Market Place.
M M M
9. import keys/secrets into the secure key storage
Both users (using the TOE’s settings UI) and administrators (using the TOE’s MDM APIs) can
import secret keys into the secure key storage.
M I
10. destroy imported keys/secrets and [no other keys/secrets] in the secure key storage
Both users and administrators (using the TOE’s MDM APIs) can destroy secret keys in the
secure key storage.
M I
11. import X.509v3 certificates into the Trust Anchor Database
Both users (using the TOE’s settings UI) and administrators (using the TOE’s MDM APIs) can
import X.509v3 certificates into the Trust Anchor Database.
M M
12. remove imported X.509v3 certificates and [no other certificates] in the Trust Anchor
Database
Both users (using the TOE’s settings UI) and administrators (using the TOE’s MDM APIs) can
remove imported X.509v3 certificates from the Trust Anchor Database as well as disable any
of the TOE’s default Root CA certificates (in the latter case, the CA certificate still resides in the
TOE’s read-only system partition; however, the TOE will treat that Root CA certificate and any
certificate chaining to it as untrusted).
M I
13. enroll the TOE in management
TOE users can enroll the TOE in management according to the instructions specific to a given
MDM. Presumably any enrollment would involve at least some user functions (e.g., install an
M M
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MDM agent application) on the TOE prior to enrollment.
14. remove applications
Both users (using the TOE’s settings UI) and administrators (using the TOE’s MDM APIs) can
uninstall user and administrator installed applications on the TOE.
M M
15. update system software
Users can check for updates and cause the device to update if an update is available. An
administrator can use MDM APIs to query the version of the TOE and query the installed
applications and an MDM agent on the TOE could issue pop-ups, initiate updates, block
communication, etc. until any necessary updates are completed.
M M
16. install applications
Both users and administrators (using the TOE’s MDM APIs) can install applications on the TOE.
M M
17. remove Enterprise applications
An administrator (using the TOE’s MDM APIs) can uninstall Enterprise installed applications on
the TOE.
M M
18. configure the Bluetooth trusted channel:
a. disable/enable the Discoverable mode (for BR/EDR)
b. change the Bluetooth device name
[k. no other Bluetooth configuration]
TOE users can enable Bluetooth discoverable mode for a short period of time and can also
change the device name which is used for the Bluetooth name. Additional wireless
technologies include Android Beam which utilizes NFC and Bluetooth, and can be enabled and
disabled by the TOE user.
M
19. enable/disable display notification in the locked state of: [
f. all notifications]
Notifications can be configured to display in the following formats:
Users & administrators: show all notification content
Users: hide sensitive content
Users & administrators: hide notifications entirely
If the administrator sets any of the above settings, the user cannot change it.
M I I
20. enable data-at rest protection
The TOE always encrypts its user data storage.
M
21. enable removable media’s data-at-rest protection
The device’s DAR protection cannot be disabled.
22. enable/disable location services:
a. across device
[d. no other method]
The administrator (using the TOE’s MDM APIs) can enable or disable location services.
An additional MDM API can prohibit TOE users ability to enable and disable location services.
M I I
23. Enable/disable the use of [selection: Biometric Authentication Factor] I I I
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24. enable/disable all data signaling over [USB]
25. enable/disable [Wi-Fi hotspot, USB tethering, and Bluetooth tethering]
The administrator (using the TOE’s MDM APIs) can enable/disable all tethering methods (i.e.
all or none disabled).
The TOE acts as a server (acting as an access point, a USB Ethernet adapter, and as a Bluetooth
Ethernet adapter respectively) in order to share its network connection with another device.
I I I
26. enable/disable developer modes
The administrator (using the TOE’s MDM APIs) can disable Developer Mode.
Unless disabled by the administrator, TOE users can enable and disable Developer Mode.
I I I
27. enable/disable bypass of local user authentication
N/A – It is not possible to bypass local user auth for this TOE
28. wipe Enterprise data
An administrator can remove Enterprise applications and their data.
I I
29. approve [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
37. configure the auditable items
38. retrieve TSF-software integrity verification values
39. enable/disable [
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 [all applications] to [remote system]
41. enable/disable [
a. Hotspot functionality authenticated by [pre-shared key],
b. USB tethering authenticated by [no authentication]]
The administrator (using the TOE’s MDM APIs) can disable the Wi-Fi hotspot and USB
tethering.
Unless disabled by the administrator, TOE users can configure the Wi-Fi hotspot with a pre-
shared key and can configure USB tethering (with no authentication).
I I I
42. approve exceptions for sharing data between [groups of application] I I I
43. place applications into application process groups based on [assignment: enterprise
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configuration settings]
44. Unenroll the TOE from management I I I
45. Enable/disable the Always On VPN protection I I I
46. Revoke Biometric template
47. [assignment: list of other management functions to be provided by the TSF]
5.1.5.3 Specification of Management Functions (Wireless LAN) (FMT_SMF_EXT.1/WLAN)
FMT_SMF_EXT.1.1/WLAN
The TSF shall be capable of performing the following management functions:
Table 3 WLAN Security Management Functions
Management Function
Function
Implemented
Available
to
User
role
Available
to
Admin
role
Restricted
to
Admin
48. 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 I
49. specify wireless networks (SSIDs) to which the TSF may connect;
An administrator can specify a list of wireless networks to which the TOE may connect and can
restrict the TOE to only allow a connection to the specified networks.
I I
50. enable/disable certificate revocation list checking;
51. disable ad hoc wireless client-to-client connection capability,
52. disable wireless network bridging capability (for example, bridging a connection between
the WLAN and cellular radios on a smartphone so it can function as a hotspot);
53. disable roaming capability;
54. enable/disable IEEE 802.1X pre-authentication;
55. enable/disable and configure PMK caching:
a. set the amount of time (in minutes) PMK entries are cached;
b. set the maximum number of PMK entries that can be cached.
5.1.5.4 Extended: Specification of Remediation Actions (FMT_SMF_EXT.2)
FMT_SMF_EXT.2.1
The TSF shall offer [wipe of protected data, wipe of sensitive data, remove Enterprise applications, remove all
device stored Enterprise resource data, remove Enterprise secondary authentication data]
upon un-enrollment and [no other triggers].
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5.1.5.5 Extended: Current Administrator (FMT_SMF_EXT.3)
FMT_SMF_EXT.3.1
The TSF shall provide a mechanism that allows users to view a list of currently authorized administrators and the
management functions that each administrator is authorized to perform.
5.1.6 Protection of the TSF (FPT)
5.1.6.1 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.
5.1.6.2 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.
5.1.6.3 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.
5.1.6.4 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.
5.1.6.5 Extended: Anti-Exploitation Services (ASLR) (FPT_AEX_EXT.5)
FPT_AEX_EXT.5.1
The TSF shall provide address space layout randomization (ASLR) to the kernel.
FPT_AEX_EXT.5.2
The base address of any kernel-space memory mapping will consist of at least 4 unpredictable bits.
5.1.6.6 Extended: 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.
5.1.6.7 Extended: JTAG Disablement (FPT_JTA_EXT.1)
FPT_JTA_EXT.1.1
The TSF shall [control access by a signing key] to JTAG.
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5.1.6.8 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.
5.1.6.9 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.
5.1.6.10 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.
5.1.6.11 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]]
5.1.6.12 Reliable time stamps (FPT_STM.1)
FPT_STM.1.1
The TSF shall be able to provide reliable time stamps for its own use.
5.1.6.13 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.
5.1.6.14 TSF Cryptographic Functionality Testing (Wireless LAN) (FPT_TST_EXT.1/WLAN)
FPT_TST_EXT.1.1/WLAN
The [TOE] shall run a suite of self-tests during initial start-up (on power on) to demonstrate the correct operation of
the TSF.
FPT_TST_EXT.1.2/WLAN
The [TOE] shall provide the capability to verify the integrity of stored TSF executable code when it is loaded for
execution through the use of the TSF-provided cryptographic services.
5.1.6.15 Extended: TSF Integrity Checking (FPT_TST_EXT.2(1))
FPT_TST_EXT.2(1).1
The TSF shall verify the integrity of the bootchain up through the Application Processor OS kernel stored in
mutable media prior to its execution through the use of [an immutable hardware hash of an asymmetric key].
5.1.6.16 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
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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.
5.1.6.17 Extended: TSF 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
software]] using a digital signature verified by the manufacturer trusted key prior to installing those updates.
FPT_TUD_EXT.2.2
The TSF shall [update only by verified software] the TSF boot integrity [key].
FPT_TUD_EXT.2.3
The TSF shall verify that the digital signature verification key used for TSF updates [matches an immutable
hardware public key].
FPT_TUD_EXT.2.4
The TSF shall verify mobile application software using a digital signature mechanism prior to installation.
5.1.7 TOE access (FTA)
5.1.7.1 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. [lock sound is played].
5.1.7.2 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.
5.1.7.3 Wireless Network Access (FTA_WSE_EXT.1)
FTA_WSE_EXT.1.1
The TSF shall be able to attempt connections only to wireless networks specified as acceptable networks as
configured by the administrator in FMT_SMF_EXT.1.1/WLAN.
5.1.8 Trusted path/channels (FTP)
5.1.8.1 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
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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].
5.1.8.2 Trusted Channel Communication (Wireless LAN) (FTP_ITC_EXT.1/WLAN)
FTP_ITC_EXT.1.1/WLAN
The TSF shall use 802.11-2012, 802.1X, and EAP-TLS to provide a trusted communication channel between itself
and a wireless access point 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/WLAN
The TSF shall initiate communication via the trusted channel for wireless access point 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.
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
Table 4 EAL 1 augmented with ALC_TSU_EXT.1 Assurance Components
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
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The functional specification shall provide rationale for the implicit categorization 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 useraccessible functions and
privileges that should be controlled in a secure processing environment, including appropriate
warnings.
AGD_OPE.1.2c
The operational user guidance shall describe, for each user role, how to use the available interfaces
provided by the TOE in a secure manner.
AGD_OPE.1.3c
The operational user guidance shall describe, for each user role, the available functions and
interfaces, in particular all security parameters under the control of the user, indicating secure
values as appropriate.
AGD_OPE.1.4c
The operational user guidance shall, for each user role, clearly present each type of security-
relevant event relative to the user-accessible functions that need to be performed, including
changing the security characteristics of entities under the control of the TSF.
AGD_OPE.1.5c
The operational user guidance shall identify all possible modes of operation of the TOE (including
operation following failure or operational error), their consequences, and implications for
maintaining secure operation.
AGD_OPE.1.6c
The operational user guidance shall, for each user role, describe the security measures to be
followed in order to fulfill 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
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The preparative procedures shall describe all the steps necessary for secure installation of the TOE
and for the secure preparation of the operational environment in accordance with the security
objectives for the operational environment as described in the ST.
AGD_PRE.1.1e
The evaluator shall confirm that the information provided meets all requirements for content and
presentation of evidence.
AGD_PRE.1.2e
The evaluator shall apply the preparative procedures to confirm that the TOE can be prepared
securely for operation.
5.2.3 Life-cycle support (ALC)
5.2.3.1 Labelling of the TOE (ALC_CMC.1)
ALC_CMC.1.1d
The developer shall provide the TOE and a reference for the TOE.
ALC_CMC.1.1c
The TOE shall be labelled with its unique reference.
ALC_CMC.1.1e
The evaluator shall confirm that the information provided meets all requirements for content and
presentation of evidence.
5.2.3.2 TOE CM Coverage (ALC_CMS.1)
ALC_CMS.1.1d
The developer shall provide a configuration list for the TOE.
ALC_CMS.1.1c
The configuration list shall include the following: the TOE itself; and the evaluation evidence
required by the SARs.
ALC_CMS.1.2c
The configuration list shall uniquely identify the configuration items.
ALC_CMS.1.1e
The evaluator shall confirm that the information provided meets all requirements for content and
presentation of evidence.
5.2.3.3 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.
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.1.4c
The description shall include where users can seek information about the availability of new
updates including details (e.g. CVE identifiers) of the specific public vulnerabilities corrected by
each update.
ALC_TSU_EXT.1.1e
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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.
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:
- Security audit
- Cryptographic support
- User data protection
- Identification and authentication
- Security management
- Protection of the TSF
- TOE access
- Trusted path/channels
6.1 Security audit
FAU_GEN.1: The TOE uses three different forms of logs to meet all the required management logging events
specified in Table 1 and Table 2 of the MDfPP:
1. Security Logs
2. Logcat Logs
3. Intents
Each of the above logging methods are described below.
 Security Logs: A table that depicts the list of all auditable events (for MDFPP31/WLANCEP10) can be
found here: https://developer.android.com/reference/android/app/admin/SecurityLog. Additionally, the
following link provides the additional information that can be grabbed when an MDM requests a copy of
the logs: https://developer.android.com/reference/android/app/admin/SecurityLog.SecurityEvent. Each
log contains a keyword or phrase describing the event, the date and time of the event, and further event-
specific values that provide success, failure, and other information relevant to the event. While these logs
can be read by an administrator via an MDM agent, no audit is generated during the event, therefore
FAU_SAR.1 is not claimed.
 Logcat Logs: Similar to Security Logs, Logcat Logs contain date, time, and further even-specific values
within the logs. In addition, Logcat Logs provide a value that maps to a user ID to identify which user
caused the event that generated the log. Finally, Logcat Logs tend to be more human-readable and
descriptive, not requiring the user to know the template of the log to understand its values. Logcat Logs
cannot be exported but can be viewed via an ADB shell to the device.
 Intents: Intents are events that are generated by applications and can be viewed by anyone in the
system. They contain all the same information as the logs above along with much more information
identifying the package/application and user that created and logged the intent. Application specific and
system wide Intents can be viewed via an ADB shell connected to the device. An MDM agent can
subscribe, monitor, and create a copy of the intents to transmit them back to the management server.
The following table enumerates the events that the TOE audits. Requirements marked with “(O)” are from the
Table 2: Additional Auditable Events of the MDFPP31. Requirements appended with “/WLAN” are audit events
required by the WLANEP10. Any requirements that are not marked with “(O)” or “/WLAN” are from Table 1 in
MDFPP31.
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Requirement Audit Event Content
FAU_GEN.1 Start-up and shutdown of the audit func-
tions
FAU_GEN.1 All administrative actions
FAU_GEN.1 Start-up and shutdown of the Rich OS
FCS_CKM.1 [None]
FCS_CKM.6 [None]
FCS_CKM_EXT.1 [None]
FCS_STG_EXT.1 Import or destruction of key. Identity of key. Role and identity of
requestor.
FCS_STG_EXT.3 Failure to verify integrity of stored key. Identity of key being verified.
FCS_TLSC_EXT.1/WLAN Failure to establish an EAP-TLS session. Reason for failure.
FCS_TLSC_EXT.1/WLAN Establishment/termination of an EAP-
TLS session.
Non-TOE endpoint of connection.
FDP_DAR_EXT.2 Failure to encrypt/decrypt data.
FDP_STG_EXT.1 Addition or removal of certificate from
Trust Anchor Database.
Subject name of certificate.
FIA_X509_EXT.1 Failure to validate X.509v3 certificate. Reason for failure of validation.
FPT_TST_EXT.1 Initiation of self-test.
FPT_TST_EXT.1 Failure of self-test.
FPT_TST_EXT.1/WLAN Execution of this set of TSF self-tests:
[none]
(Done as part of FPT_TST_EXT.1)
FPT_TST_EXT.2(1) Start-up of TOE.
FTA_WSE_EXT.1 All attempts to connect to access points. Identity of access point being con-
nected to as well as success and fail-
ures (including reason for failure).
FTP_ITC_EXT.1/WLAN All attempts to establish a trusted chan-
nel.
(TD0194 applied)
Identification of the non-TOE end-
point of the channel.
Table 5 Audit Events
FAU_STG.1: For security logs, the TOE stores all audit records in memory, making it only accessible to the logd
daemon, and only device owner applications can call the MDM API to retrieve a copy of the logs. Additionally, only
new logs can be added. There is no designated method allowing for the deletion or modification of logs already
present in memory, but reading the security logs clears the buffer at the time of the read.
For Logcat Logs, these are stored in memory and can only be accessed via an ADB Shell. These logs can be deleted,
but only by the phone’s administrator after enabling USB Debugging accesses from the phone’s settings.
Intents follow the same flow as the Logcat Logs described in the paragraph above in all respects, except that they
cannot be deleted by an administrator. There is no method to allow designated deletion of intents by any
administrator or user.
FAU_STG.4: The security log, logcat and intents are stored in memory in a circular log buffer of 10KB/64KB/NA,
respectively. Once the log is full, it begins overwriting the oldest message and continues overwriting the oldest
message with each new auditable event. For intents, since there is no defined size of the buffer (the limit is the
free storage size of the device), there is no overwriting of the oldest log. The buffer size for intents increases and
decreases as intents are created or destroyed. The number of intents drives the size of the buffer, as opposed to
the buffer size limiting the number of intents present. The lifetime of intents depends on how applications and
processes leveraging them define their use.
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6.2 Cryptographic support
FCS_CKM.1: The TOE provides generation of asymmetric keys including
Algorithm Key/Curve Sizes Usage
RSA, FIPS 186-4 2048/3072/4096 API/Application & Sensitive Data Protection
(DAR.2)
ECDSA, FIPS 186-4 P-256/384 API/Application
ECDHE keys (not domain parameters) P-256/384 TLS KeyEx (WPA2 w/ EAP-TLS & HTTPS)
Table 6 Asymmetric Key Generation
The TOE’s cryptographic algorithm implementations have received NIST algorithm certificates (please see Table 7,
Table 8, and Table 9 in FCS_COP.1 for all of the TOE’S algorithm certificates). The TOE itself does not generate any
RSA/ECDSA authentication key pairs for TOE functionality (the user or administrator must load certificates for use
with WPA2 with EAP-TLS authentication); however, the TOE provides key generation APIs to mobile applications to
allow them to generate RSA/ECDSA key pairs. The TOE generates only ECDH key pairs (as BoringSSL does not
support DH/DHE cipher suites) and does not generate domain parameters (curves) for use in TLS Key Exchange.
The TOE will provide a library for application developers to use for Sensitive Data Protection (SDP). This library
(class) generates asymmetric 4096 bit RSA keys for use to encrypt and decrypt data that comes to the device while
in a locked state. Any data received for a specified application (that opts into SDP via this library), is encrypted
using the public key and stored until the device is unlocked. The public key stays in memory no matter the state of
the device (locked or unlocked). However, when the device is locked, the private key is evicted from memory and
unavailable for use until the device is unlocked. Upon unlock, the private key is re-derived and used to decrypt
data received and encrypted while locked.
FCS_CKM.1/WLAN: The TOE adheres to IEEE 802.11-2012 and IEEE 802.11ac-2014 for key generation. The TOE’s
wpa_supplicant provides the PRF384 and PRF704 for WPA2 derivation of 128-bit and 256-bit AES Temporal Key
(using the HMAC implementation provided by BoringSSL) and employs its BoringSSL AES-256 DRBG when generat-
ing random values used in the EAP-TLS and 802.11 4-way handshake. The TOE supports the AES-128 CCMP and
AES-256 CCMP encryption mode. The TOE has successfully completed certification (including WPA2 Enterprise) and
received Wi-Fi CERTIFIED Interoperability Certificates from the Wi-Fi Alliance. The Wi-Fi Alliance maintains a web-
site providing further information about the testing program: http://www.wi-fi.org/certification.
Device Name Model Number Wi-Fi Alliance Certificate Numbers
Pixel 3 G103A/B WFA77734
Pixel 3 XL G103C/D WFA78505
FCS_CKM.2(1): The TOE performs key establishment as part of EAP-TLS and TLS session establishment. Table 6
Asymmetric Key Generation enumerates the TOE’S supported key establishment implementations (RSA/ECDH for
TLS/EAP-TLS).
FCS_CKM.2(2): The TOE provides an SDP library for applications that uses a hybrid crypto scheme based on 4096-
bit RSA based key establishment. Applications can utilize this library to implement SDP that encrypts incoming
data received while the phone is locked in a manner compliant with this requirement.
FCS_CKM.2.1/WLAN: The TOE adheres to RFC 3394 and 802.11-2012 standards and unwraps the GTK (sent en-
crypted 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 Root Encryption Key (REK) stored in a 256-bit fuse bank within the application
processor. The TOE generates the REK/fuse value during manufacturing using its hardware DRBG. The application
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processor protects the REK by preventing any direct observation of the value and prohibiting any ability to modify
or update the value. The application processor loads the fuse value into an internal hardware crypto register and
the Trusted Execution Environment (TEE) provides trusted applications the ability to derive KEKs from the REK
(using an SP 800-108 KDF to combine the REK with a salt). Additionally, the when the REK is loaded, the fuses for
the REK become locked, preventing any further changing or loading of the REK value. The TEE does not allow
trusted applications to use the REK for encryption or decryption, only the ability to derive a KEK from the REK. The
TOE includes a TEE application that calls into the TEE in order to derive a KEK from the 256-bit REK/fuse value and
then only permits use of the derived KEK for encryption and decryption as part of the TOE key hierarchy. More
information regarding Trusted Execution Environments may be found here:
http://www.globalplatform.org/mediaguidetee.asp.
FCS_CKM_EXT.2: The TOE utilizes its approved RBGs to generate DEKs. When generating AES keys for itself (for
example, the TOE’S sensitive data encryption keys or for the Secure Key Storage), the TOE utilizes the
RAND_bytes() API call from its BoringSSL AES-256 CTR_DRBG to generate a 256-bit AES key. The TOE also utilizes
that same DRBG when servicing API requests from mobile applications wishing to generate AES keys (either 128 or
256-bit).
In all cases, the TOE generates DEKs using a compliant RBG seeded with sufficient entropy so as to ensure that the
generated key cannot be recovered with less work than a full exhaustive search of the key space.
FCS_CKM.2(2): The TOE uses ECDH with a P-256 curve key establishment for protection of application sensitive
data received while the device is locked.
FCS_CKM_EXT.3: The TOE derives all password-based KEKs by combining the user’s password with a BoringSSL
RBG generated salt value using scrypt. Scrypt uses HMAC-SHA-256 (an iteration of PBKDFv2), followed by ROMix
operations that increase the required memory manipulation (slowing the ability of brute-force attacks), finally
sandwiched with another iteration of PBKDFv2. See FCS_COP.1 for a more thorough explanation of scrypt.
The TOE generates all non-derived KEKs using the RAND_bytes() API call from its BoringSSL AES-256 CTR_DRBG to
ensure a full 150/256-bits of strength for asymmetric/symmetric keys, respectively. And the TOE combines KEKs by
encrypting one KEK with the other so as to preserve entropy.
FCS_CKM_EXT.4: The TOE clears sensitive cryptographic material (plaintext keys, authentication data, other
security parameters) from memory when no longer needed or when transitioning to the device’s locked state (in
the case of the Sensitive Data Protection keys). Public keys (such as the one used for Sensitive Data Protection) can
remain in memory when the phone is locked, but all crypto-related private keys are evicted from memory upon
device lock. No plaintext cryptographic material resides in the TOE’S Flash as 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 Data-At-Rest DEK. Because the TOE’S keystore resides within the user data partition, the TOE
effectively cryptographically erases those keys when clearing the Data-At-Rest DEK. In turn, the TOE clears the
Data-At-Rest DEK and Secure Key Storage SEK through a secure direct overwrite (BLKSECDISCARD ioctl) of the
wear-leveled Flash memory containing the key followed by a read-verify.
FCS_CKM_EXT.5: The TOE stores all protected data in encrypted form within the user data partition (either
protected data or sensitive data). Upon request, the TOE cryptographically erases the Data-At-Rest DEK protecting
the user data partition and the SDP Master KEK protecting sensitive data files in the user data partition, clears
those keys from memory, reformats the partition, and then reboots. The TOE’s clearing of the keys follows the
requirements of FCS_CKM_EXT.4.
FCS_CKM_EXT.6: The TOE generates salt nonces (which are just salt values used in WPA2) using its /dev/urandom.
Salt value and size RBG origin Salt storage location
User password salt (128-bit) BoringSSL’s AES-256 CTR_DRBG Flash filesystem
TLS client_random (256-bit) BoringSSL’s AES-256 CTR_DRBG N/A (ephemeral)
TLS pre_master_secret (384-bit) BoringSSL’s AES-256 CTR_DRBG N/A (ephemeral)
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TLS ECDHE private value (256, 384) BoringSSL’s AES-256 CTR_DRBG N/A (ephemeral)
WPA2 4-way handshake supplicant
nonce (SNonce)
BoringSSL’s AES-256 CTR_DRBG N/A (ephemeral)
FCS_COP.1: The TOE implements cryptographic algorithms in accordance with the following NIST standards and
has received the following CAVP algorithm certificates.
The TOE’s BoringSSL Library provides the following algorithms (BoringSSL code can be found here:
https://android.googlesource.com/platform/external/boringssl/+/android-cts-9.0_r1):
SFR Algorithm NIST Standard Cert#
FCS_CKM.1 (Key Gen) RSA IFC Key Generation FIPS 186-4, RSA C782
ECDSA ECC Key Generation FIPS 186-4, ECDSA C782
FCS_CKM.2 (Key Establishment) RSA-based Key Exchange Vendor affirm 800-56B N/A
ECC-based Key Exchange SP 800-56A, CVL KAS ECC C782
FCS_COP.1(1) (AES) AES 128/256 CBC, GCM, KW FIPS 197, SP 800-38A/D/F C782
FCS_COP.1(2) (Hash) SHA Hashing FIPS 180-4 C782
FCS_COP.1(3) (Sign/Verify) RSA Sign/Verify FIPS 186-4, RSA C782
ECDSA Sign/Verify FIPS 186-4, ECDSA C782
FCS_COP.1(4) (Keyed Hash) HMAC-SHA 1/256/384/512 FIPS 198-1 & 180-4 C782
FCS_RBG_EXT.1 (Random)
FCS_CKM_EXT.2
DRBG Bit Generation SP 800-90A (Counter)
C782
Table 7 BoringSSL Cryptographic Algorithms
The TOE’s Trusted Execution Environment's Kernel software (in this case QTEE 5.0) and Android’s LockSettings
service provides the TOE’S key based key derivation function.
SFR Algorithm NIST Standard Cert#
FCS_CKM_EXT.3 KBKDF SP 800-108 KDF171
FCS_CKM_EXT.3 LockSettings service KBKDF SP 800-108 C831
Table 8 KDF Cryptographic Algorithms
The TOE’s Wi-Fi chipset provides an AES-CCMP implementation, and the TOE’s application processor (Snapdragon
845 [SDM845]) provide additional cryptographic algorithms.
SFR Algorithm NIST Standard Cert#
FCS_COP.1(1) (AES) (Wi-Fi) AES 128/256 CCM FIPS 197, SP 800-38C 4748
FCS_COP.1(1) (AES) (QTI CEC*) AES 128/256 CBC FIPS 197, SP 800-38A 4959
FCS_COP.1(1) (AES) (QTI UFS**) AES 128/256 XTS FIPS 197, SP 800-38E 4958/4957
FCS_COP.1(2) (Hash) (QTI CEC) SHA 1/256 Hashing FIPS 180-4 4049
FCS_COP.1(2) (Hash) (DRBG) SHA 256 Hashing FIPS 180-4
4047,
4048
FCS_COP.1(4) (Keyed Hash) (QTI CEC) HMAC-SHA-1/256 FIPS 198-1 & 180-4 3305
FCS_RBG_EXT.1 (Random) (DRBG)
FCS_CKM_EXT.2
DRBG Bit Generation SP 800-90A (Hash-256)
1788
Table 9 SDM845 Hardware Cryptographic Algorithms
*QTI CEC – Qualcomm Technologies, Inc. Crypto Engine Core v5.4.1
**QTI UFS - Qualcomm Technologies, Inc. Inline Crypto Engine (UFS) v3.1.0
The TOE’s application processor includes a source of hardware entropy that the TOE distributes throughout, and
the TOE’s RBGs make use of that entropy when seeding/instantiating themselves.
The TOE’s BoringSSL library supports the TOE’s cryptographic Android Runtime (ART) methods (through Android's
conscrypt JNI provider) afforded to mobile applications and also supports Android user-space processes and
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daemons (e.g., wpa_supplicant). The TOE’s Application Processor provides hardware accelerated cryptography
utilized in Data-At-Rest (DAR) encryption of the user data partition.
The TOE stretches the user’s password to create a password derived key. The TOE stretching function uses a series
of steps to increase the memory required for key derivation (thus thwarting GPU-acceleration, off-line brute force,
and precomputed dictionary attacks) and ensure proper conditioning and stretching of the user’s password.
The TOE conditions the user’s password using two iterations of PBKDFv2 w HMAC-SHA-256 in addition to some
ROMix operations in an algorithm named scrypt. Scrypt consists of one iteration of PBKDFv2, followed by a series
of ROMix operations, and finished with a final iteration of PBKDFv2. The ROMix operations increase the memory
required for key derivation, thus thwarting GPU-acceleration (which can greatly decrease the time needed to brute
force PBKDFv2 alone).
The following scrypt diagram shows how the password and salt are used with PBKDFv2 and ROMix to fulfil the
requirements for password conditioning.
The resulting derived key from this operation is used to decrypt the FBE DEK (see the key hierarchy above for
further explanation on how this key is used in FBE) and to derive the User Keystore Daemon Value.
The TOE uses HMAC as part of the TLS ciphersuites and makes HMAC functionality available to mobile applications.
For TLS, the TOE uses HMAC using SHA-1 (with a 160-bit key) to generate a 160-bit MAC, SHA-256 (with a 256-bit
key) to generate a 256-bit MAC, SHA-384 (with a 384-bit key) to generate a 384-bit MAC. For mobile applications,
the TOE provides all of the previous HMACs as well as SHA-512 (with a 512-bit key) to generate a 512-bit MAC.
FIPS 198-1 & 180-4 dictate the block size used, and they specify block sizes/output MAC lengths of 512/160,
512/160, 1024/384, and 1024/512-bits for HMAC-SHA-1, HMAC-SHA-256, HMAC-SHA-384, and HMAC-SHA-512
respectively.
FCS_HTTPS_EXT.1: The TOE supports the HTTPS protocol (compliant with RFC 2818) so that (mobile and system)
applications executing on the TOE can act as HTTPS clients and securely connect to external servers using HTTPS.
Administrators have no credentials and cannot use HTTPS or TLS to establish administrative sessions with the TOE
as the TOE does not provide any such capabilities.
FCS_IV_EXT.1: The TOE generates IVs by reading from /dev/urandom for use with all keys. In all cases, the TOE
uses /dev/urandom and generates the IVs in compliance with the requirements of table 11 of
MDFPP31/WLANCEP10.
FCS_RBG_EXT.1: The TOE provides a number of different RBGs including:
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1. A SHA-256 Hash_DRBG provided in the hardware of the Application Processor.
2. An AES-256 CTR_DRBG provided by BoringSSL. This is the only accredited and supported DRBG present in
the system and available to independently developed applications. As such, the TOE provides mobile
applications access (through an Android Java API) to random data drawn from its AES-256 CTR_DRBG.
The TOE initializes its AP Hash_DRBG with enough data from its hardware noise source to ensure at least 256-bits
of entropy. The TOE then uses its AP Hash_DRBG to to continuously fill the Linux Kernel Random Number
Generator input pool.
The TOE seeds its BoringSSL AES-256 CTR_DRBG using 384-bits of data from /dev/urandom, thus ensuring at least
256-bits of entropy. The TOE uses its BoringSSL DRBG for all random generation uses outside of salts.
FCS_SRV_EXT.1: The TOE provides applications access to the cryptographic operations including encryption (AES),
hashing (SHA), signing and verification (RSA & ECDSA), key hashing (HMAC), keyed message digests (HMAC-SHA-
256), generation of asymmetric keys for key establishment (RSA and ECDH), and generation of asymmetric keys for
signature generation and verification (RSA, ECDSA). The TOE provides access through the Android operating
system’s Java API, through the native BoringSSL API, and through the application processor module (user and
kernel) APIs.
FCS_SRV_EXT.2: The TOE provides applications with APIs to perform the functions referenced in FCS_COP.1(1) and
FCS_COP.1(3).
FCS_STG_EXT.1: The TOE provides the user, administrator, and mobile applications the ability to import and use
asymmetric public and private keys into the TOE’S software-based Secure Key Storage. Additionally, the user and
administrator can request the TOE to destroy the keys stored in the Secure Key Storage. 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 (and which explicitly declare a shared UUID in their application manifest) may use and destroy each
other’s keys located within the Secure Key Storage.
FCS_STG_EXT.2: The TOE employs a key hierarchy that protects all DEKs and KEKs by encryption with either the
REK or by the REK and password derived KEK.
Long-term Trusted channel Key Material (BlueTooth and WiFi keys) are encrypted using AES encryption.
Additionally, all LTTCKM is subject to an SHA-256 checksum verification to verify the integrity of the two files
containing LTTCKM (Wi-Fi PSKs and BT keys).
All keys are 256-bits in size. All keys are generated using the TOE’S BoringSSL AES-256 CTR_DRBG or application
processor SHA-256 Hash_DRBG. By utilizing only 256-bit KEKs, the TOE ensures that all keys are encrypted by an
equal or larger sized key.
In the case of Wi-Fi, the TOE utilizes the 802.11-2012 KCK and KEK keys to unwrap (decrypt) the WPA2 Group
Temporal Key received from the access point. The TOE protects persistent Wi-Fi keys (user certificates and private
keys) by storing them in the Secure Key Store.
FCS_STG_EXT.3: The TOE protects the integrity of all DEKs and KEKs (other than LTTCKM keys) stored in Flash by
using authenticated encryption/decryption methods (CCM, GCM). The TOE protects the two files containing Wi-Fi
and BT LTTCKM keys through a SHA-256 checksum used for integrity verification and encrypts that checksum using
an AES-GCM-256 key protected by the TOE’s secure key storage (KeyStore).
FCS_TLSC_EXT.1/2: The TOE provides mobile applications (through its Android API) the use of TLS version 1.2
including support for the selections in chosen in section 5 for FCS_TLSC_EXT.1.
When an application uses the APIs provided in the Admin Guide to attempt to establish a trusted channel
connection based on EAP-TLS, TLS or HTTPS, the TOE supports only Subject Alternative Name (SAN) (DNS and IP
address) as reference identifiers (the TOE does not accept reference identifiers in the Common Name[CN]). The
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TOE supports client (mutual) authentication. The TOE in its evaluated configuration and by design, supports only
evaluated elliptic curves for TLS (P-256 & P-384 and no others) and has a fixed set of supported curves (thus the
admin cannot and need not configure any curves). While the TOE supports the use of wildcards in X.509 reference
identifiers (SAN only), the TOE does not support certificate pinning. If the TOE cannot determine the revocation
status of a peer certificate, the TOE provides the ability for application developers to select what happens for their
application: give the user the option to connect/disconnect, deny the connection, or connect anyways.
FCS_TLSC_EXT.1/2/WLAN: The TSF supports TLS versions 1.0, 1.1, and 1.2 and also supports the selected
ciphersuites utilizing SHA-1, SHA-256, and SHA-384 (see the selections in section 5 for FCS_TLSC_EXT.1/WLAN) for
use with EAP-TLS as part of WPA2. The TOE in its evaluated configuration and by design, supports only evaluated
elliptic curves (P-256 & P-384 and no others) and has a fixed set of supported curves (thus the admin cannot and
need not configure any curves).
The TOE, allows the user to load and utilize authentication certificates for EAP-TLS used with WPA. The Android UI
(Settings->Security->Credential storage: Install from device storage) allows the user to import an RSA or ECDSA
certificate and designate its use as WiFi.
6.3 User data protection
FDP_ACF_EXT.1.1: 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 cannot automatically grant it to the requesting application. For example, any
dangerous permissions requested by an application will be displayed to the user and require confirmation
before proceeding or some other approach can 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. Please avoid using this option, as the signature
protection level should be sufficient for most needs and works regardless of exactly where applications
are installed. 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 request (or 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 running 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 application is allowed to continue running. If the user
disapproves, the devices continues to run, but cannot use the services protected by the denied permissions.
Thereafter, the mobile device grants that application during execution access to the set of permissions declared in
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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 (2nd
installed app) that requests this permission and
that has been signed with the same developer key used to sign the application (1st
installed app) declaring the
permission (in the case of the example, the Android Framework itself).
An example of a signatureOrSystem 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.
1. privileged - this permission can also be granted to any applications installed as privileged apps on the
system image. Please avoid using this option, as the signature protection level should be sufficient for
most needs and works regardless of exactly where applications are installed. This permission flag 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.
2. system - Old synonym for 'privileged'.
3. development - this permission can also (optionally) be granted to development applications (e.g., to allow
additional location reporting during beta testing).
4. appop - this permission is closely associated with an app op for controlling access.
5. pre23 - this permission can be automatically granted to apps that target API levels below API level 23
(Marshmallow/6.0).
6. installer - this permission can be automatically granted to system apps that install packages.
7. verifier - this permission can be automatically granted to system apps that verify packages.
8. preinstalled - this permission can be automatically granted to any application pre-installed on the system
image (not just privileged apps) (the TOE does not prompt the user to approve the permission).
For older applications (those targeting Android’s pre-23 API level, i.e., API level 22 [lollipop] and below), the TOE
will prompt a user at the time of application installation whether they agree to grant the application access to the
requested services. Thereafter (each time the application is run), the TOE will grant the application access to the
services specified during install.
For newer applications (those targeting API level 23 or later), the TOE grants individual permissions at application
run-time by prompting the user for confirmation of each permissions category requested by the application (and
only granting the permission if the user chooses to grant it).
The Android 9.0 (Level 28) API found here https://developer.android.com/about/versions/pie/android-9.0
provides a description of the services available to mobile applications.
While Android provides a large number of individual permissions, they are generally grouped into categories or
features that provide similar functionality. Table 10 shows a series of functional categories centered on common
functionality.
Service Features Description
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Service Features Description
Sensitive I/O Devices & Sensors Location services, Audio & Video capture, Body sensors
User Personal Information & Credentials Contacts, Calendar, Call logs, SMS
Metadata & Device ID Information IMEI, Phone Number
Data Storage Protection App data, App cache
System Settings & Application Manage-
ment
Date time, Reboot/Shutdown, Sleep, Force-close application, Ad-
ministrator Enrollment
Wi-Fi, Bluetooth, USB Access Wi-Fi, Bluetooth, USB tethering, debugging and file transfer
Mobile Device Management & Admin-
istration
MDM APIs
Peripheral Hardware NFC, Camera, Headphones
Security & Encryption Certificate/Key Management, Password, Revocation rules
Table 10 – Functional Categories
FDP_ACF_EXT.1.2: Applications with a common developer have the ability to allow sharing of data between their
applications. A common application developer can sign their generated APK with a common certificate or key and
set the permissions of their application to allow data sharing. When the different applications’ signatures match
and the proper permissions are enabled, information can then be shared as needed.
The TOE supports Enterprise profiles to provide additional separation between application and application data
belonging to the Enterprise profile. Applications installed into the Enterprise versus Personal profiles cannot access
each other’s secure data, applications, and can have separate device administrators/managers. This functionality is
built into the device by default and does not require an application download. The Enterprise administrative app
(an MDM agent application installed into the Enterprise Profile) may enable cross-profile contacts search, in which
case, the device owner can search the address book of the enterprise profile. Please see the Admin Guide for
additional details regarding how to set up and use Enterprise profiles. Ultimately, the enterprise profile is under
control of the personal profile. The personal profile can decide to remove the enterprise profile, thus deleting all
information and applications stored within the enterprise profile. However, despite the “control” of the personal
profile, the personal profile cannot dictate the enterprise profile to share applications or data with the personal
profile; the enterprise profile MDM must allow for sharing of contacts before any information can be shared.
FDP_ACF_EXT.2: The TOE allows an administrator to allow sharing of the enterprise profile address book with the
normal profile.
FDP_DAR_EXT.1: The TOE provides Data-At-Rest AES-256 XTS hardware 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 Secure Key Store. The TOE separately encrypts those TSF keys and
data. Additionally, the TOE includes a read-only filesystem in which the TOE’S system executables, libraries, and
their configuration data reside. For its Data-At-Rest encryption of the data partition on the internal Flash (where
the TOE stores all user data and all application data), the TOE uses an AES-256 bit DEK with XTS feedback mode to
encrypt each file in the data partition using dedicated application processor hardware.
FDP_DAR_EXT.2: The TOE provides a Java library for Sensitive Data Protection (SDP) that application developers
can use to opt-in for sensitive data protection. When developers opt-in for SDP, all data that is received on the
device destined for that application is treated as sensitive. This library generates a 4096 bit RSA key that acts as a
master KEK for the SDP encryption process. When an application that has opted-in for SDP receives incoming data
while the device is locked, a 256 bit AES symmetric DEK is generated to encrypt that data. The public key from the
master RSA KEK above is then used to encrypt the AES DEK. Once the device is unlocked, the RSA KEK private key is
re-derived and can be used to decrypt the AES DEK for each piece of information that was stored while the device
was locked. The TOE then takes that decrypted data and re-encrypts it following FDP_DAR_EXT.1.
FDP_IFC_EXT.1: The TOE will route all traffic other than traffic necessary to establish the VPN connection to the
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VPN gateway (when the gateway’s configuration specifies so). The TOE includes an interceptor kernel module that
controls inbound and output packets. When a VPN is active, the interceptor will route all incoming packets to the
VPN and conversely route all outbound packets to the VPN before they are output.
The only exception to all traffic being routed to the VPN is in the instance of ICMP echo requests. The TOE uses
ICMP echo responses on the local subnet to facilitate network troubleshooting and categorizes it as a part of ARP.
As such, if an ICMP echo request is issued on the subnet the TOE is part of, it will respond with an ICMP echo
response, but no other instances of traffic will be routed outside of the VPN.
FDP_PBA_EXT.1: The TOE requires the user to enter their password to enroll, re-enroll or un-enroll any biometric
templates. When the user attempts biometric authentication to the TOE, the biometric sensor takes an image of
the presented biometric for comparison to the enrolled templates. The captured image is compared to all the
stored templates on the device to determine if there is a match. The complete biometric authentication process is
handled inside the TEE (including image capture, all processing and match determination). The image is provided
to the biometric service to check the enrolled templates for a match to the captured image.
FDP_STG_EXT.1: The TOE’S Trusted Anchor Database consists of the built-in certs and any additional user or
admin/MDM loaded certificates. The built-in certs are individually stored in the device’s read-only system image in
the /system/etc/security/cacerts directory, and the user can individually disable certs through Android’s user
interface [Settings->Security-> Trusted Credentials]. Because the built-in CA certificates reside on the read-only
system partition, the TOE places a copy of any disabled built-in certificate into the /data/misc/user/X/cacerts-
removed/ directory, where 'X' represents the user’s number (which starts at 0). The TOE stores added CA
certificates in the corresponding /data/misc/user/X/cacerts-added/ directory and also stores a copy of the CA
certificate in the user’s Secure Key Storage (residing in the /data/misc/keystore/user_X/ directory). The TOE uses
Linux file permissions that prevent any mobile application or entity other than the TSF from modifying these files.
Only applications registered as an administrator (such as an MDM Agent Application) have the ability to access
these files, staying in accordance to the permissions established in FMT_SMF_EXT.1 and FMT_MOF_EXT.1.
FDP_UPC_EXT.1: The TOE provides APIs allowing non-TSF applications (mobile applications) the ability to establish
a secure channel using TLS, HTTPS, and Bluetooth DR/EDR and LE. Mobile applications can use the following
Android APIs for TLS, HTTPS, and Bluetooth respectively:
SSL:
javax.net.ssl.SSLContext:
https://developer.android.com/reference/javax/net/ssl/SSLSocket
Developers then need to swap SocketFactory for SecureSocketFactory, part of a private library provided by Google.
Developers can request this library by emailing: niapsec@google.com
HTTPS:
javax.net.ssl.HttpsURLConnection:
https://developer.android.com/reference/javax/net/ssl/HttpsURLConnection
Developers then need to swap HTTPSUrlConnections for SecureUrl part of a private library provided by Google.
Developers can request this library by emailing: niapsec@google.com
Bluetooth:
android.bluetooth:
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http://developer.android.com/reference/android/bluetooth/package-summary.html
6.4 Identification and authentication
FIA_AFL_EXT.1: The TOE maintains in persistent storage, for each user, the number of failed password logins since
the last successful login (the phone, in its evaluated configuration, only supports password authentication), 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 for the cryptlock screen from the
default of ten failed logins to a value between 0 (deactivate wiping) and 2,147,483,647 through an MDM. The TOE
validates passwords by providing them to Android’s Gatekeeper (which runs in the Trusted Execution
Environment). If the presented password fails to validate, the TOE increments the incorrect password counter
before displaying a visual error to the user. Android’s Gatekeeper keeps this password counter in secure storage
and is incremented before the password is validated. Upon successful validation of the password, this counter is
reset back to zero.
Additionally, the phone allows the user to unlock the device using a fingerprint sensor. The user has up to 5
attempts to unlock the device before the fingerprint sensor is temporarily disabled for 30 seconds. While the
sensor is disabled, the user can input their password to unlock the phone. After a total of 4 failed rounds of
attempted fingerprint unlock (20 total unlock attempts), the fingerprint sensor is disabled entirely until the user
enters their password to unlock the device. Note that restarting the phone at any point disables the fingerprint
sensor automatically until the user enters a correct password and unlocks the phone, and therefore TOE restart
disruptions are not applicable for this authentication mechanism.
FIA_BLT_EXT.1: The TOE requires explicit user authorization before it will pair with a remote Bluetooth device.
When pairing with another device, the TOE requires that the user either confirm that a displayed numeric
passcode matches between the two devices or that the user enter (or choose) a numeric passcode that the peer
device generates (or must enter). The TOE requires this authorization (via manual input) for mobile application use
of the Bluetooth trusted channel and in situations where temporary (non-bonded) connections are formed.
FIA_BLT_EXT.2: The TOE prevents data transfer of any type until Bluetooth pairing has completed. Additionally,
the TOE supports OBEX (OBject Exchange) through L2CAP (Logical Link Control and Adaptation Protocol).
FIA_BLT_EXT.3: The TOE rejects duplicate Bluetooth connections by only allowing a single connection per paired
device.
FIA_BLT_EXT.4: The TOE’S Bluetooth host and controller supports Bluetooth Secure Simple Pairing and the TOE
utilizes this pairing method when the remote host also supports it.
FIA_BLT_EXT.6: The TOE requires explicit user authorization before granting trusted remote devices access to
services associated with the OPP and MAP Bluetooth profiles. Additionally, the TOE requires explicit user
authorization before granting untrusted remote devices access to services associated with all following Bluetooth
profiles.
FIA_BMG_EXT.1: The TOE’s fingerprint sensor provides a FAR of 1:100,000 with an FRR of 3.1%, which is rounded
and mapped to a 1:25 rate. Prior to the rounding, the 3.1% FRR meets the requirements for FIA_BMG_EXT.
Users have up to 5 attempts to unlock the phone using fingerprint before the fingerprint unlock method is disabled
for 30 seconds. After the 4th unsuccessful round of unlock attempts (a total of 20 fingerprint attempts), the
fingerprint sensor is disabled entirely and the user is prompted for their password. The fingerprint unlock remains
disabled until the user enters their password.
Since the user can attempt to unlock the phone a total of 20 times before the fingerprint is disabled, the SAFAR of
the phone is 1:5,000.
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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 authenticates the user through a password consisting of basic Latin characters (upper
and lower case, numbers, and the special characters noted in the selection (see the selections in section 5 for
FIA_PMG_EXT.1)). The TOE defaults to requiring passwords to have a minimum of four characters but no more
than sixteen, contain at least one letter; however, an MDM application can change these defaults. The Smart Lock
feature is not allowed in the evaluated config as this feature circumvents the requirements for FIA_PMG_EXT.1
and many others.
FIA_TRT_EXT.1: Android’s GateKeeper throttling is used to prevent brute-force attacks. After a user enters an
incorrect password, GateKeeper APIs return a value in milliseconds (500ms default) in which the caller must wait
before attempting to validate another password. Any attempts before the defined amount of time has passed will
be ignored by GateKeeper. Gatekeeper also keeps a count of the number of failed validation attempts since the
last successful attempt. These two values together are used to prevent brute-force attacks of the TOE’s password.
FIA_UAU.5: The TOE, in its evaluated configuration, allows the user to authenticate using either a password or
fingerprint. Upon boot, the first unlock screen presented requires the user to enter their password to unlock the
device. The fingerprint sensor is disabled until the user enters their password for the first time.
Upon device lock during normal use of the device, the user has the ability to unlock the phone either by entering
their password or using fingerprint authentication. Throttling of these inputs can be read about in the
FIA_AFL_EXT.1 section. The entered password is compared to a value derived as described in Section 6.1.
FIA_BMG_EXT.1 describes the password authentication process and its security measures.
Some security related user settings (e.g. changing the password, modifying, deleting, or adding stored fingerprint
templates, SmartLock settings, etc.) and actions (e.g. factory reset) require the user to enter their password before
modifying these settings or executing these actions. In these instances, fingerprint authentication is not accepted
to permit the referenced functions.
The TOE’s evaluated configuration disallows other authentication mechanisms, such as pattern, PIN, or Smart Lock
mechanisms (on-body detection, trusted places, trusted devices, trusted face, trusted voice).
FIA_UAU.7: The TOE allows the user to enter the user's password from the 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: As described before, the TOE’s key hierarchy requires the user's password in order to derive the
KEK_* keys in order to decrypt other KEKs and DEKs. Thus, until it has the user's password, the TOE cannot decrypt
the DEK utilized for Data-At-Rest encryption, and thus cannot decrypt the user’s protected data.
FIA_UAU_EXT.2: The TOE, when configured to require a user password, allows a user to perform the actions
assigned in FIA_UAU_EXT.2.1 (see selections in section 5 for FIA_UAU_EXT.2) without first successfully
authenticating. Choosing the input method allows the user to select between different keyboard devices (say, for
example, if the user has installed additional keyboards). Note that the TOE automatically names and saves (to the
internal Flash) any screen shots or photos taken from the lock screen, and the TOE provides the user no
opportunity to name them or change where they are stored.
When configured, the user can also launch Google Assistant to initiate some features of the phone. However, if the
command requires access to the user’s data (e.g. contacts for calls or messages), the phone requires the user to
manually unlock the phone before the action can be completed.
Beyond those actions, a user cannot perform any other actions other than observing notifications displayed on the
lock screen until after successfully authenticating. Additionally, the TOE provides the user the ability to hide the
contents of notifications once a password (or any other locking authentication method) is enabled.
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FIA_UAU.6(1)/FIA_UAU.6(2): The TOE requires the user to enter their password or supply their biometric in order
to unlock the TOE. Additionally, the TOE requires the user to confirm their current password when accessing the
“Settings->Display->LockScreen->Screen Security->Select screen lock” menu in the TOE’s user interface. The TOE
can disable Smart Lock through management controls. 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 as the TOE imports the certificate. 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 if not yet valid, whether the certificate
contains the appropriate X.509 extensions [e.g., 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.
FIA_X509_EXT.2/FIA_X509_EXT.2/WLAN: The TOE uses X.509v3 certificates during EAP-TLS, TLS, and HTTPS. The
TOE comes with a built-in set of default Trusted Credentials (Android's set of trusted CA certificates), and while the
user cannot remove any of the built-in default CA certificates, the user can disable any of those certificates
through the user interface so that certificates issued by disabled CA’s cannot validate successfully. In addition, a
user and an administrator/MDM can import a new trusted CA certificate into the Trust Anchor Database (the TOE
stores the new CA certificate in the Security Key Store).
The TOE does not establish TLS connections itself (beyond EAP-TLS used for WPA2 Wi-Fi connections), but provides
a series of APIs that mobile applications can use to check the validity of a peer certificate. The mobile application,
after correctly using the specified APIs, can be assured as to the validity of the peer certificate and be assured that
the TOE will not establish the trusted connection if the peer certificate cannot be verified (including validity,
certification path, and revocation [through OCSP]). If, during the process of certificate verification, the TOE cannot
establish a connection with the server acting as the OCSP Responder, the TOE will not deem the server’s certificate
as valid and will not establish a TLS connection with the server.
The user or administrator explicitly specifies the trusted CA that the TOE will use for EAP-TLS authentication of the
server’s certificate. For mobile applications, the application developer will specify whether the TOE should use the
Android system Trusted CAs, use application-specified trusted CAs, or a combination of the two. In this way, the
TOE always knows which trusted CAs to use.
The TOE, when acting as a WPA2 supplicant uses X.509 certificates for EAP-TLS authentication. Because the TOE
may not have network connectivity to a revocation server prior to being admitted to the WPA2 network and
because the TOE cannot determine the IP address or hostname of the authentication server (the Wi-Fi access point
proxies the supplicant’s authentication request to the server), the TOE will accept the certificate of the server.
FIA_X509_EXT.3: The NIAPSEC library created by the vendor provides the following functions to allow for
certificate path validation and revocation checking:
- public boolean isValid(List<Certificate> certs)
- public Boolean isValid(Certificate cert)
The first function allows for validation and revocation checking against a list of certificates, while the second
checks a singular certificate. Revocation checking is completed using OCSP. Please see the FIA_X509_EXT.2/WLAN
section for a further explanation on how the TOE handles revocation checking.
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6.5 Security Management
FMT_MOF_EXT.1/FMT_SMF_EXT.1: The TOE provides the management functions described in Table 2 Security
Management Functions in section 5. The table includes annotations describing the roles that have access to each
service and how to access the service. The TOE enforces administrative configured restrictions by rejecting user
configuration (through the UI) when attempted. It is worth noting that the TOE’S ability to specify authorized
application repositories takes the form of allowing enterprise applications (i.e., restricting applications to only
those applications installed by an MDM Agent).
FMT_SMF_EXT.1/WLAN: The TOE provides the management functions described in Table 3 WLAN Security
Management Functions in section 5. As with Table 2 Security Management Functions, the table includes
annotations describing the roles that have access to each service and how to access the service. The TOE enforces
administrative configured restrictions by rejecting user configuration (through the UI) when attempted. It is worth
noting that the TOE’S ability to specify authorized application repositories takes the form of allowing enterprise
applications (i.e., restricting applications to only those applications installed by an MDM Agent).
FMT_SMF_EXT.2: The TOE offers MDM agents the ability to wipe protected data, wipe sensitive data, remove
Enterprise applications, remove all device stored Enterprise resource data, and remove Enterprise secondary
authentication data upon un-enrollment. The TOE offers MDM agents the ability to wipe protected data
(effectively wiping the device) at any time. Similarly, the TOE also offers the ability to remove Enterprise
applications and a full wipe of managed profile data of the TOE’S Enterprise data/applications at any time.
FMT_SMF_EXT.3: The TOE offers MDM agents and the user (through the “Settings->Security->Device
administrators” menu) the ability to view each application that has been granted admin rights, and further to see
what operations each admin app has been granted.
6.6 Protection of the TSF
FPT_AEX_EXT.1: The Linux kernel of the TOE’S Android operating system provides 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 Android 9.0 operating system utilizes 4.9.148 Linux kernels
(https://source.android.com/devices/architecture/kernel/modular-kernels#core-kernel-requirements), whose
memory management unit (MMU) enforces read, write, and execute permissions on all pages of virtual memory
and ensures that write and execute permissions are not simultaneously granted on all memory. 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'. Section D.5 of the ARMv8
Architecture Reference Manual contains additional details about the MMU of ARM-based processors:
http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0487a.f/index.html.
FPT_AEX_EXT.3: The TOE’s 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 gcc-fstack-protector compile
option to enable stack overflow protection and Android takes advantage of hardware-based eXecute-Never to
make the stack and heap non-executable. The vendor applies these protections to all TSF executable binaries and
libraries.
FPT_AEX_EXT.4: The TOE protects itself from modification by untrusted subjects using a variety of methods. The
first protection employed by the TOE 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.
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The TOE protects its REK by limiting access to only trusted applications within the TEE (Trusted Execution
Environment). The TOE key manager includes a TEE module which utilizes the REK to protect all other keys in the
key hierarchy. All TEE applications are cryptographically signed, and when invoked at runtime (at the behest of an
untrusted application), the TEE will only load the trusted application after successfully verifying its cryptographic
signature.
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 access the memory space
or files of other applications (notwithstanding access between applications with a common application developer).
The TOE, in its evaluated configuration has its bootloader in the locked state. This prevents a user from installing a
new software image via another method than Google’s proscribed OTA methods. The TOE allows an operator to
download and install an OTA update through the system settings (Settings->System->Advanced->System update-
>Check for update) while the phone is running, or by separately downloading an OTA image, and then
“sideloading” the OTA update from Android’s recovery mode. In both cases, the TOE will verify the digital
signature of the new OTA before applying the new firmware.
For the first install of the Common Criteria compliant build, the administrator must unlock the device’s bootloader
via the fastboot interface, “sideload” the correct build, reboot the phone back to the fastboot interface, re-lock the
bootloader, and finally start the phone normally. For both the locking and unlocking of the bootloader, the device
is factory reset as part of the process. This prevents an attacker from modifying or switching the image running on
the device to allow access to sensitive data. After this first install of the official build, further updates can be done
via normal OTA updates.
FPT_AEX_EXT.5: The TOE models provide Kernel Address Space Layout Randomization (KASLR) as a hardening
feature to randomize the location of kernel data structures at each boot, including the core kernel as a random
physical address, mapping the core kernel at a random virtual address in the vmalloc area, loading kernel modules
at a random virtual address in the vmalloc area, and mapping system memory at a random virtual address in the
linear area. The entropy used to dictate the randomization is based on the hardware present within the phone. For
ARM devices, such as the TOE, 13–25 bits of entropy are generated on boot, from which the starting memory
address is generated.
FPT_BBD_EXT.1: The TOE’S hardware and software architecture ensures separation of the application processor
(AP) from the baseband or communications processor (CP) through internal controls of the TOE’S SoC, which
contains both the AP and the CP. The AP restricts hardware access control through a protection unit that restricts
software access from the baseband processor through a dedicated 'modem interface'. The protection unit
combines the functionality of the Memory Protection Unit (MPU), the Register Protection Unit (RPU), and the
Address Protection Unit (APU) into a single function that conditionally grants access by a master to a software
defined area of memory, to registers, or to a pre-decoded address region, respectively. The modem interface
provides a set of APIs (grouped into five categories) to enable a high-level OS to send messages to a service
defined on the modem/baseband processor. The combination of hardware and software restrictions ensures that
the TOE’S AP prevents software executing on the modem or baseband processor from accessing the resources of
the application processor (outside of the defined methods, mediated by the application processor).
FPT_JTA_EXT.1: The TOE’S prevents access to its processor’s JTAG interface by requiring use of a signing key to
authenticate prior to gaining JTAG access. Only a JTAG image with the accompanying device serial number (which
is different for each mobile device) that has been signed by Google’s private key can be used to access a device’s
JTAG interface. The Google private key corresponds to the Google RSA 2048-bit public key (a SHA-256 hash of
which is fused into the TOE’S application processor).
FPT_KST_EXT.1: The TOE does not store any plaintext key material in its internal Flash; the TOE encrypts all keys
before storing them. 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 stored in the internal Flash are
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wrapped with a KEK. Please refer to section 6.2 of the TSS for further information (including the KEK used)
regarding the encryption of keys stored in the internal Flash. As 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
cryptographic libraries including BoringSSL, application processor cryptography (which leverages AP hardware),
and the following system-level executables that utilize KEKs: dm-crypt, wpa_supplicant, and the Secure Key Store.
1. QCT’s dm-crypt and application processor hardware provides Data-At-Rest encryption of the user data
partition in Flash
2. wpa_supplicant provides 802.11-2014/WPA2 services
3. the Secure Key Store application provides key generation, storage, deletion services to mobile
applications and to user through the UI
The TOE ensures that plaintext key material is not exported by not allowing the REK to be exported and by
ensuring that only authenticated entities can request utilization of the REK. Furthermore, the TOE only allows the
system-level executables access to plaintext DEK values needed for their operation. The TSF software (the system-
level executables) protects those 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). Note that the TOE does not
use the user’s biometric fingerprint to encrypt/protect key material (and instead only relies upon the user’s
password).
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.
Furthermore, the components of the device are designed to prevent transmission of key material outside the
device. Each internal system component requiring access to a plaintext key (for example the Wi-Fi driver) must
have the necessary precursor(s), whether that be a password from the user or file access to key in Flash (for
example the encrypted AES key used for encryption of the Flash data partition). With those appropriate
precursors, the internal system-level component may call directly to the system-level library to obtain the plaintext
key value. The system library in turn requests decryption from a component executing inside the trusted execution
environment and then directly returns the plaintext key value (assuming that it can successfully decrypt the
requested key, as confirmed by the CCM/GCM verification) to the calling system component. That system
component will then utilize that key (in the example, the dm-crypt daemon that holds the key in order to encrypt
and decrypt reads and writes to the encrypted user data partition in Flash). In this way, only the internal system
components responsible for a given activity have access to the plaintext key needed for the activity, and that
component receives the plaintext key value directly from the system library.
For a user’s mobile applications, those applications do not have any access to any system-level components and
only have access to keys that the application has imported into the Secure Key Store. Upon requesting access to a
key, the mobile application receives the plaintext key value back from the system library through the Android API.
Mobile applications do not have access to the memory space of any other mobile application so it is not possible
for a malicious application to intercept the plaintext key value to then log or transmit the value off the device.
FPT_NOT_EXT.1: When the TOE encounters a critical failure (either a self-test failure or TOE software integrity
verification failure), a failure is message is displayed to the screen, and the TOE attempts to reboot. If the failure
persists between boots, the user may attempt to boot to the recovery mode/kernel to wipe data and perform a
factory reset in order to recover the device.
FPT_STM.1: The TOE requires time for the Package Manager (which installs and verifies APK signatures and
certificates), image verifier, wpa_supplicant, and Secure Key Store applications. These TOE components obtain
time from the TOE using system API calls [e.g., time() or gettimeofday()]. An application (unless a system
application is residing in /system/priv-app or signed by the vendor) cannot modify the system time as mobile
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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. Further, this stored time is used both for the time/date tags in audit logs and is used to
track inactivity timeouts that force the TOE into a locked state.
FPT_TST_EXT.1: The TOE automatically performs known answer power on self-tests (POST) on its cryptographic
algorithms to ensure that they are functioning correctly. Each component providing cryptography (application
processor, and BoringSSL) performs known answer tests on their cryptographic algorithms to ensure they are
working correctly. Should any of the tests fail, the TOE displays an error message stating “Boot Failure” and halts
the boot process, displays an error to the screen, and forces a reboot of the device.
Algorithm Implemented in Description
AES encryption/decryption BoringSSL Comparison of known answer to calculated value
ECDH key agreement BoringSSL Comparison of known answer to calculated value
DRBG random bit generation BoringSSL Comparison of known answer to calculated value
ECDSA sign/verify BoringSSL Comparison of known answer to calculated value
HMAC-SHA BoringSSL Comparison of known answer to calculated value
RSA sign/verify BoringSSL Comparison of known answer to calculated value
SHA hashing BoringSSL Comparison of known answer to calculated value
AES encryption/decryption Application Processor Comparison of known answer to calculated value
HMAC-SHA Application Processor Comparison of known answer to calculated value
DRBG random bit generation Application Processor Comparison of known answer to calculated value
SHA hashing Application Processor Comparison of known answer to calculated value
AES-XTS encrypt/decrypt Application Processor Comparison of known answer to calculated value
Table 11 Power-up Cryptographic Algorithm Known Answer Tests
FPT_TST_EXT.2(1): 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, verifies the signature of the Linux kernel it
loads. Additionally, the TOE performs checking of the entire /system partition through use of Android’s dm_verity
mechanism (and while the TOE will still operate, it will log any blocks/executables that have been modified).
FPT_TUD_EXT.1: The TOE’S user interface provides a method to query the current version of the TOE
software/firmware (Android version, baseband version, kernel version, build number, and software version) and
hardware (model and 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 verifies all OTA (Over The Air) updates to the TOE software (which includes baseband
processor updates) using a public key chaining ultimately to the Root Public Key, a hardware protected key whose
SHA-256 hash resides inside the application processor. Should this verification fail, the software update will fail and
the update will not be installed.
The application processor verifies the bootloader’s authenticity and integrity (thus tying the bootloader and
subsequent stages to a hardware root of trust: the SHA-256 hash of the Root Public Key, which cannot be
reprogrammed after the “write-enable” fuse has been blown).
The Android OS on the TOE requires that all applications bear a valid signature before Android will install the
application.
The TOE also provides roll-back protection for OTA updates to prevent a user from installing a prior/previous
version of software. Using the bootloader update method, administrators can circumvent this roll-back protection.
However, to be able to access the bootloader, an attacker would need unlock access to the phone. Additionally,
should an attacker gain the ability to unlock the boot loader, the process of unlocking the bootloader triggers a full
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wipe of the phone, preventing any sensitive information from remaining on the phone after a roll-back attack.
ALC_TSU_EXT.1: Google supports a bug filing system for the Android OS outlined here:
https://source.android.com/setup/contribute/report-bugs. This allows developers or users to search for, file, and
vote on bugs that need to be fixed. This helps to ensure that all bugs that affect large numbers of people get
pushed up in priority to be fixed. The method outlined above requires the user to submit their bug to Android’s
website. As such, the user of the device needs to establish a trusted channel web connection to securely file the
bug by following the set-up steps to establish a secure HTTPS/TLS/EAP-TLS connection from the TOE, then visiting
the above web portal to submit the report.
Google also commits to pushing out monthly security updates for the Android operating system (including the Java
layer and kernel, not including applications). Monthly security updates have historically been supported on Google
products for 3 years after release. These systematic updates are designed to address the highest issue problems as
quickly as possible and allows Google to ensure their Pixel products remain as safe as possible and any issues are
addressed promptly.
Google’s creates updates and patches to resolve reported issues as quickly as possible, at which point the update is
provided to the wireless carriers. The delivery time for resolving an issue depends on the severity, and can be as
rapid as a few days before the carrier handoff for high priority cases. The wireless carriers perform additional tests
to ensure the updates will not adversely impact their networks and then plan device rollouts once that testing is
complete. Carrier updates usually take at least two weeks to as much as two months (depending on the type and
severity of the update) to be rolled out to customers. However, the Carriers also release monthly Maintenance
Releases in order to address security-critical issues. Google maintains a security blog (https://android-
developers.googleblog.com/) to disseminate information directly to the public.
6.7 TOE access
FTA_SSL_EXT.1: The TOE transitions to its locked state either immediately after a User initiates a lock by pressing
the power button (if configured) or after a (also configurable) period of inactivity, and as part of that transition, the
TOE will display a lock screen to obscure the previous contents and play a “lock sound” to indicate the phone’s
transition; however, the TOE’S lock screen still displays email notifications, calendar appointments, user configured
widgets, text message notifications, the time, date, call notifications, battery life, signal strength, and carrier
network. But without authenticating first, a user cannot perform any related actions based upon these
notifications (they cannot respond to emails, calendar appointments, or text messages) other than the actions
assigned in FIA_UAU_EXT.2.1 (see selections in section 5).
Note that during power up, the TOE presents the user with an unlock screen. While at this screen, users can access
some basic device functionality (e.g. making an emergency call) and basic system data is decrypted. Once the user
enters their password, the user data partition is then decrypted and the full functionality of the phone is unlocked.
After this initial screen, upon (re)locking the phone, the user is presented with an “unlock for all features and data”
unlock screen. This screen puts the phone in the same state as the aforementioned lock screen, encrypting user
data and locking any functionality that requires data that is decrypted by the user’s password. While locked, the
actions described in FIA_UAU_EXT.2.1 are available for the user to utilize.
FTA_TAB.1: The TOE can be configured to display a user-specified message on the Lock screen, and additionally an
administrator can also set a Lock screen message using an MDM.
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, the security type, authentication protocol,
and the client credentials to be used for authentication. 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 user 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 WiFi radio.
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6.8 Trusted path/channels
FTP_ITC_EXT.1/FTP_ITC_EXT.1/WLAN: The TOE provides secured (encrypted and mutually authenticated)
communication channels between itself and other trusted IT products through the use of IEEE 802.11-2012,
802.1X, and EAP-TLS and TLS. The TOE permits itself and applications to initiate communicate via the trusted
channel, and the TOE initiates communications via the WPA2 (IEEE 802.11-2012, 802.1X with EAP-TLS) trusted
channel for connection to a wireless access point. The TOE provides mobile applications and MDM agents access
to HTTPS and TLS via published APIs, thus facilitating administrative communication and configured enterprise
connections. These APIs 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 that are used to provide the security functionality of the
device. Each of the below are built with the -fstack-protector-strong option set. For each binary/library, the name,
path, and security function are provided.
Name Path Security Function
keystore /system/bin Key Store
gatekeeperd /system/bin Key MGMT
qseecomd /system/bin DAR
time_daemon /system/bin Time
vold /system/bin DAR
wpa_supplicant /system/bin WPA2
adbd /system/bin
Security System
Settings/Recovery
libcrypto.so /system/lib Crypto
libcrypto.so /system/lib64 Crypto
libkeystore_binder.so /system/lib KeyStore
libkeystore_binder.so /system/lib64 KeyStore
libkeyutils.so /system/lib64 DAR
libssl.so /system/lib SSL/TLS
libssl.so /system/lib64 SSL/TLS
update_engine_sideload /recovery/root/sbin Recovery/Initial Image Load
recovery /recovery/root/sbin Recovery
mke2fs_static /recovery/root/sbin Recovery
charger /recovery/root/sbin Recovery
init /recovery/root Recovery